PATIENT MONITORING DEVICE

Abstract

A patient-moving device (1) for patient handling. The device (1) includes a chassis (3), patient-support (5), and knee-rest (37). The device (1) includes a primary pivot (17) and a secondary pivot (11) located eccentrically from the primary pivot (17). A reorientation mechanism (4) is coupled to the patient-support (5), primary pivot (17) and chassis (3). During operation to reorientate the reorientation mechanism (4) during patient handling the patient support (5) is movable relative to the chassis (3) by rotation of the primary pivot (17) and/or secondary pivot (11) and the knee rest (37) is movable relative to at least a portion of the chassis (3).

Claims

1. A patient-moving device for patient handling, said patient handling including raising and lowering a seated patient between sitting and transport positions, and moving a raised patient in the transport position, said device including: a terrain-engaging mobile chassis; a primary pivot, pivotable about a primary pivot axis; a secondary pivot, pivotable about a secondary pivot axis and located eccentrically from said primary pivot; a patient-support, formed to engage with, and at least partially support, a patient's anterior torso during patient handling; at least one knee-rest, formed to engage with, and at least partially support, a patient's anterior knee surfaces during patient handling; a reorientation mechanism, and coupled to said patient-support, said primary pivot and said chassis, wherein: operation to reorientate the reorientation mechanism during patient handling to raise or lower a seated patient between the sitting and transport positions respectively re-orientates the patient support between a patient loading/unloading configuration and a patient transport configuration; said secondary pivot axis is located below and parallel to said primary pivot axis; the at least one knee rest is movable relative to at least a portion of the chassis and is connected to, or proximal to, or located at, said primary pivot, and wherein said patient support is movable relative to the chassis by rotation of said primary pivot and said secondary pivot.

2. A patient-moving device as claimed in claim 1, wherein the at least one knee rest is movable relative to at least a portion of the chassis by being pivotable about a tertiary pivot axis, the tertiary pivot axis located eccentrically from said primary pivot axis.

3. (canceled)

4. (canceled)

5. (canceled)

6. A patient-moving device as claimed in claim 1, wherein the at least one knee rest movement during patient handling correlates with, or is proximal to, the movement of said primary pivot.

7. A patient-moving device as claimed in claim 1, wherein the secondary pivot axis is located on the chassis.

8. (canceled)

9. (canceled)

10. (canceled)

11. (canceled)

12. (canceled)

13. (canceled)

14. A patient-moving device as claimed in claim 1, including a patient securement strap extending from the patient moving device and configured to form a loop around at least the patient's posterior torso in use.

15. A patient-moving device as claimed in claim 14, wherein the patient securement strap is securable to the at a position subtending an angle of φ˜60° (+/−7.5°) from vertically upright with the patient support orientated in said patient loading configuration.

16. (canceled)

17. (canceled)

18. (canceled)

19. (canceled)

20. (canceled)

21. (canceled)

22. (canceled)

23. A patient-moving device as claimed in claim 1, wherein the at least one knee-rest is attached to the reorientation mechanism.

24. (canceled)

25. (canceled)

26. (canceled)

27. (canceled)

28. (canceled)

29. A patient-moving device as claimed in claim 1, wherein the at least one knee-rest is attached to the reorientation mechanism such that the at least one knee-rest rotates about the secondary pivot axis as the patient support rotates about the primary pivot axis.

30. (canceled)

31. A patient-moving device as claimed in claim 1, configured such that during operation to reorientate the patient support through an angular movement θ between a patient loading/unloading configuration and a patient transport configuration via reorientation of the coupled reorientation mechanism, said reorientation mechanism is configured such that the primary pivot moves in an arc though an angle Ω about the secondary pivot axis, where angles θ, Ω, and ratios θ:Ω are selected from one of: v. θ=90° to 45°, Ω=5° to 30°, θ:Ω ratio=18 to 1.5; vi. θ=90° to 50°, Ω=11.5° to 25°, θ:Ω ratio=7.8 to 2; vii. θ=60° to 80°, Ω=14° to 21°, θ:Ω ratio=5.7 to 2.9; viii. θ=70°, Ω=15°, and θ:Ω ratio=4.7.

32. (canceled)

33. A patient-moving device as claimed in claim 1, configured such that during operation to reorientate the patient support between a patient loading/unloading configuration and a patient transport configuration via manipulation of the coupled reorientation mechanism, a torso inclination angle rotates though an angle θ, while said primary pivot moves in an arc though an angle Ω about the secondary pivot and a distance δ, where angles Ω, θ and distance δ and ratios δ:θ are selected from one of: i. Ω=5° to 30°, θ=90° to 45°, δ=40 to 250 mm δ:θ=5.6 to 0.45 mm/° ii. Ω=11.5° to 25°, θ=90° to 50°, δ=80 to 180 mm δ:θ=3.6-0.9 mm/° iii. Ω=14° to 21°, θ=80° to 60°, δ=100 to 150 mm δ:θ=2.5-1.25 mm/° iv. Ω=15°, θ=70°, δ=130 mm δ:θ=1.8 mm/°.

34. (canceled)

35. A patient-moving device as claimed in claim 1, wherein said reorientation mechanism includes a multi-bar linkage(.), said multi-bar linkage including: a first support link pivotable relative to the chassis about the second pivot; a second support link pivotable relative to the chassis about a third pivot; a coupler link pivotally attached to the first support link at the first pivot and pivotally attached to the second support link at a fourth pivot, wherein the moveable patient support is coupled to the coupler link.

36. (canceled)

37. (canceled)

38. (canceled)

39. (canceled)

40. (canceled)

41. (canceled)

42. (canceled)

43. (canceled)

44. (canceled)

45. (canceled)

46. A patient-moving device as claimed in claim 1, wherein the path traversed during patient handling by at least one point of the patient support, reorientation mechanism, and/or any other point of the patient securely engaged with the patient support is defined by at least one corresponding averaged center of-rotation located in front of the patient's knee in the horizontal plane and substantially at or below the knee and above the ankle in the vertical plane, said averaged center of-rotation calculated from at least a start point, mid-point and end point of the patient handling to raise or lower a seated patient between the initial sitting position and the transport position, wherein said averaged centre-of-rotation is located within at least one of: a rectangular region 250 mm×450 mm horizontally and vertically respectively, and positioned 50 mm horizontally towards the patient and 400 mm vertically downwards from the primary pivot; a rectangular region 175 mm×325 mm horizontally and vertically respectively, and positioned 50 mm horizontally towards the patient and 400 mm vertically downwards from the primary pivot; a rectangular region extending 150 mm horizontally towards the patient and 300 mm vertically from the primary pivot.

47. (canceled)

48. A patient moving device as claimed in claim 1, including: a first support link pivotable relative to the chassis about a second pivot; a second support link pivotable relative to the chassis about a fourth pivot; a coupler link pivotally attached to the first support link at a first pivot, and pivotally attached to the second support link at a third pivot, wherein the patient support is mounted in fixed relation to the coupler link; an operating handle operably attached to the coupler link for moving the device between the patient loading/unloading configuration and the patient-transport configuration, and wherein movement of the coupler link and thereby the patient support is constrained by the first and second support links.

49. (canceled)

50. (canceled)

51. A patient moving device as claimed in claim 48, wherein the chassis, first support link, second support link, and coupler link form a four-bar mechanism of a crossover type, wherein, in the transport position, a virtual line extending between the first pivot and the third pivot intersects a virtual line extending between the second pivot and the fourth pivot.

52. (canceled)

53. (canceled)

54. (canceled)

55. (canceled)

56. (canceled)

57. (canceled)

58. (canceled)

59. (canceled)

60. (canceled)

61. (canceled)

62. A patient moving device as claimed in claim 48, wherein, in the patient loading/unloading position, the first pivot is substantially vertically aligned with the second pivot.

63. (canceled)

64. (canceled)

65. (canceled)

66. (canceled)

67. (canceled)

68. (canceled)

69. (canceled)

70. (canceled)

71. (canceled)

72. A patient-moving device for patient handling, said patient handling including raising and lowering a seated patient between sitting and transport positions, and moving a raised patient in the transport position, said device including: a terrain-engaging mobile chassis; a primary pivot, pivotable about a primary pivot axis; a secondary pivot, pivotable about a secondary pivot axis and located eccentrically from said primary pivot axis; a patient-support, formed to engage with, and at least partially support, a patient's anterior torso during patient handling; at least one knee-rest, formed to engage with, and at least partially support, a patient's anterior knee surfaces during patient handling; a reorientation mechanism, coupled to said patient-support and chassis, wherein: operation to reorientate the reorientation mechanism during patient handling to raise or lower a seated patient between sitting and transport positions respectively re-orientates the patient support between a patient loading/unloading configuration and a patient transport configuration, and said patient support is movable relative to the chassis by rotation of said primary pivot and/or said secondary pivot about the primary pivot axis, and wherein, with respect to said primary pivot axis, during said patient handling, relative rotational movement of said: chassis; patient-support; secondary pivot; reorientation mechanism; a representative Center of Mass (CoM); tertiary pivot; chassis midpoint; chassis endpoint; midpoint of a patient-engaging outer surface of the patient-support; lowermost point of a patient-engaging outer surface of the patient-support; operating handle distal end; patient securement strap patient support attachment point; patient securement strap reorientation mechanism attachment point; reorientation mechanism spatial extremity; any part of same; and any other point on said patient-moving device, are defined by movement through a predetermined angular range Ø (where Ø is measured clockwise and where 0° is vertical) forming a corresponding annulus sector or arc, each annulus sector or arc being individually defined by said predetermined angular range Ø and radius range r, wherein at least two of said annulus sector or arcs have a constant radius range r.

73. (canceled)

74. (canceled)

75. A patient moving device as claimed in claim 72, wherein, for said predetermined angular range Ø, said predetermined radius range r is constant for said CoM and at least one of said secondary and tertiary pivots.

76. A patient moving device as claimed in claim 72, wherein said predetermined angular range Ø and radius r includes at least one of: CoM arc with Ø=208.5-278.5° (for θ=70°) and r=434 mm; secondary pivot arc with Ø=180°-198.5° (for θ=70° and Ω=15°) and r=41 mm; chassis midpoint with Ø=208.5-278.5° (for θ=70°) and r=434 mm; lowermost point of a patient-engaging outer surface of the patient-support with Ø=280-350° (for θ=70°) and r=310 mm; patient securement strap patient support attachment point with Ø=24-94.5° (for θ=70°) and r=560 mm, and/or patient securement strap reorientation mechanism attachment point with Ø=16-86° (for θ=70°) and r=975 mm.

77. (canceled)

78. (canceled)

79. (canceled)

80. (canceled)

81. A method of patient handling using a patient-moving device for patient handling, said patient-moving device including: a terrain-engaging mobile chassis; a primary pivot, pivotable about a primary pivot axis; a secondary pivot, pivotable about a secondary pivot axis and located eccentrically from said primary pivot; a patient-support, formed to engage with, and at least partially support, a patient's anterior torso during patient handling; at least one knee-rest, formed to engage with, and at least partially support, a patient's anterior knee surfaces during patient handling; a reorientation mechanism, and coupled to said patient-support, said primary pivot and said chassis, wherein: operation to reorientate the reorientation mechanism during patient handling to raise or lower a seated patient between the sitting and transport positions respectively re-orientates the patient support between a patient loading/unloading configuration and a patient transport configuration; said secondary pivot axis is located below and parallel to said primary pivot axis; the at least one knee rest is movable relative to at least a portion of the chassis and is connected to, or proximal to, or located at, said primary pivot, and wherein said patient support is movable relative to the chassis by rotation of said primary pivot and said secondary pivot, said patient handling including raising and lowering a seated patient between sitting and transport positions, and moving a raised patient in the transport position, said method including: operation to reorientate the reorientation mechanism during patient handling to raise or lower a seated patient between an initial sitting position and a transport position, re-orientating the patient support between a patient loading/unloading configuration and a patient transport configuration; said patient support moving relative to the chassis by rotation of said primary pivot and/or said secondary pivot, and the at least one knee rest moving relative to at least a portion of the chassis.

82. A method of patient handling as claimed in claim (78) 81, further including: fitting a patient securement strap in a loop around the patient's torso posterior, and securing the patient securement strap to at least one of: i. the patient support; ii. the operating handle; and iii. the reorientation mechanism adjusting the patient securement strap to engage the patient with the patient support, such that the patient securement strap is securable to the patient support at a position subtending an angle of φ˜60° (+/−7.5°) from vertically upright with the patient support orientated in said patient loading configuration.

83. (canceled)

84. (canceled)

Description

BRIEF DESCRIPTION OF DRAWINGS

[0418] The present invention will now be described by way of example only and with reference to the accompanying drawings in which:

[0419] FIG. 1 is a schematic side elevation of an exemplary patient, showing relevant parts and angles;

[0420] FIG. 2 is a rear perspective view of a patient moving device according to one preferred embodiment;

[0421] FIG. 3 is a front perspective view of the patient moving device of FIG. 2 with various components removed to show other components not visible in FIG. 2;

[0422] FIG. 4 is a rear perspective view of a patient moving device according to a second preferred embodiment;

[0423] FIG. 5 is a front perspective view of the patient moving device of FIG. 4 with various components removed to show other components not visible in FIG. 4;

[0424] FIGS. 6A and 6B are partial side section views of the embodiment of FIGS. 2 and 3 in a patient loading/unloading configuration showing the effective links of a four-bar linkage, where FIG. 6A shows the device and FIG. 6B shows an enlarged schematic view of the four-bar linkage;

[0425] FIGS. 7A and 7B are partial side section views of the embodiment of FIGS. 2 and 3 in a patient-transport configuration showing the effective links of a four-bar linkage, where FIG. 7A shows the device and FIG. 7B shows an enlarged schematic view of the four-bar linkage;

[0426] FIGS. 8A to 8C are side views of the device of FIGS. 4 and 5 schematically showing a carer operating the device to move a person onto the device for transport, where FIG. 5A shows the device in the patient loading/unloading configuration, FIG. 5B shows the device in an intermediate configuration, and FIG. 5C shows the device in the patient-transport configuration;

[0427] FIG. 9 shows a schematic diagram of use of the device of FIGS. 2-3 during the patient reorientation between an initial sitting position (patient carer indicated in solid lines) and a transport position (patient carer indicated in dashed lines);

[0428] FIG. 10 shows a schematic diagram of the patient movement in a prior art device with static knee-rests;

[0429] FIG. 11A is a schematic side elevation of a patient moving device according to a third embodiment;

[0430] FIG. 11B is a schematic side elevation of a patient moving device according to a third embodiment;

[0431] FIG. 12 shows a schematic diagram of patient movement using a device with a primary pivot axis in a different location to preceding embodiments;

[0432] FIG. 13 is a schematic of a person showing their body position in a seated position for engaging with a patient moving device according to preferred embodiments;

[0433] FIG. 14 shows an enlarged part view of FIG. 13, additionally showing patient center of mass and knee movement;

[0434] FIGS. 15A and 15B show schematic diagrams of patient movement using the patient movement device of FIGS. 2-3 in a loading/unloading configuration (FIG. 15A) and a transport configuration (FIG. 15B);

[0435] FIG. 16 shows a schematic diagram of patient movement using the patient movement device of FIGS. 2-3 in a transport configuration without using a securement strap;

[0436] FIG. 17A shows a schematic diagram of the patient movement device of FIGS. 2-3 in a loading/unloading configuration using a securement strap;

[0437] FIG. 17B shows a schematic diagram of the patient movement device of FIGS. 2-3 in a loading/unloading configuration showing the securement strap as the handle is rotated;

[0438] FIG. 18A shows a schematic diagram of the patient movement device of FIGS. 2-3 in a loading/unloading configuration using an alternative securement strap;

[0439] FIG. 18B shows a schematic diagram of the patient movement device of FIGS. 2-3 in a loading/unloading configuration showing the securement strap as the handle is rotated;

[0440] FIGS. 19A and 19B show schematic diagrams of patient movement using a patient movement device according to a fifth embodiment, in a loading/unloading configuration (FIG. 19A) and a transport configuration (FIG. 19B);

[0441] FIGS. 20A and 20B show schematic diagrams of patient movement using a patient movement device according to a sixth embodiment, in a loading/unloading configuration (FIG. 16A) and a transport configuration (FIG. 16B);

[0442] FIG. 21A shows a schematic diagram of the movement trajectories of averaged centre of rotations of patient components during patient handling;

[0443] FIG. 21B shows an enlarged view of the review of FIG. 21A adjacent the primary pivot axis/knee joint axis;

[0444] FIG. 22A shows a schematic diagram of the movement trajectories of centroid positions of patient components during patient handling;

[0445] FIG. 22B shows an enlarged view of the review of FIG. 22A adjacent the primary pivot axis/knee joint axis;

[0446] FIG. 23 shows a schematic diagram of the movement trajectories of device components during patient handling;

[0447] FIG. 24 shows a graphical plot representation of the movement trajectories shown in FIG. 23, with respect to the primary pivot axis at the plot origin;

[0448] FIG. 25 shows a similar graphical plot representation as FIG. 24 but of the movement trajectories of exemplary prior art devices;

[0449] FIG. 26 shows a similar graphical plot representation as FIG. 24 but of the movement trajectories of exemplary prior art devices.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

[0450]

TABLE-US-00001 1 patient moving device 46 Spring 2 Terrain 47 Upper crossbars 3 chassis 48 Lower crossbars 4 Reorientation mechanism 49 Jugular Notch path 5 Patient-support/chest-pad 50 CoM movement path 6 operating handle 51 Handle movement path 7 first support link 52 Prior art pivot axis 8 Chest pad adjustment handle 53 Locking pin hole 9 second support link 54 patient-support sliding adjustment member 10 Multi-bar linkage 55 coupler link locking pin 11 secondary pivot 56 patient securement strap 12 carer 57 strap hooks 13 third pivot 58 Strap securement point 14 Upper frame 59 position locking means 15 coupler link 60 Upper lock pivot 16 patient armrests 61 Lower lock pivot 17 primary pivot 62 Jugular notch 18 Link straps 63 torso 19 fourth pivot 64 femur 20 Primary pivot axis 65 tibia 21 Secondary pivot axis 66 Hip joint/axis 22 Tertiary pivot axis 67 Prior art knee rests 23 Bracing handle 68 Ankle joint/axis 24 Carer foot lever 69 Centre of mass (CoM) 25 patient 70 Centre of mass aggregation region 26 Rear wheels 71 hip CoR 27 Front wheels 72 CoM CoR 28 Knee pads 73 Jugular notch CoR 29 legs 74 hip centroid 30 Knee pad bolts 75 CoM centroid 31 front pivots 76 Jugular notch centroid 32 Knee rest bracket slots 77 Effective pivot region 33 wheel locks 78 patient rotation line 34 Locking lever 79 knee rotation line 35 footrests 80 Geared mechanism 36 foot 81 slidable carriage 37 knee-rest 82 curved track 38 knee joints/axis 83 track geometric centre 39 patient-support surface 84 quadrant gear 40 Knee contact surfaces 85 gear track 41 Knee bracket 86 Carriage coupler portion 42 Lateral knee restraints 87 track attachment point 43 patient handle 88 electrical drive 44 knee-pad mounting link 89 drive pivot 45 Knee rest pivot 90 Prior art tibia line 100 Tracked embodiment 91 Prior art CoM arc 200 Electric embodiment β Hip Angle L Effective First Link θ Torso Angle P Effective Second Link Ω Tibia/shin angle S Effective Coupler Link λ Interior Knee Angle Q Effective Frame Link ϕ Link strap angle

[0451] FIGS. 2-9 show exemplary embodiments of a patient moving device (1) for patient handling. Patient handling includes raising and lowering a seated patient between sitting and transport positions and moving a raised patient in the transport position.

[0452] The patient moving device (1) has a patient side or ‘rear’ side P and an opposite carer side or ‘front’ side C. The patient handling involves raising and lowering a seated patient between sitting and transport positions and moving a raised patient in the transport position.

[0453] An arrow marked “F” has been inserted into the figures where appropriate to indicate a forward direction of the device, the front of the device being the carer side, and the rear of the device being the opposite, patient loading side.

[0454] Accordingly the terms forward, rearward, left side, and right side (or similar) should be construed with reference to the forward direction F of the device, not necessarily with reference to the orientation shown in a given figure, the use of these terms is for ease of explanation and is not intended to be limiting.

[0455] It will also be understood that any angular orientation term referenced with respect to the patient moving device and herein described, or defined with respect to both an orientation and a clockwise or anticlockwise rotation therefrom, should be interpreted as being viewed from an observer with the patient or ‘rear’ side of the patient moving device to the observer's left and the carer or ‘front’ side to the observer's right.

[0456] It will be noted that all figures and graphical representation shown are not necessarily to scale, nor geometrically accurate and are for illustrative purposes only.

[0457] FIG. 1 shows a schematic phantom outline view of an exemplary seated patient (25), overlaid on a symbolic representation designating relevant features, elements and locations of the patient's body referenced as follows: [0458] Jugular Notch, (62); [0459] torso (63); [0460] femur (64); [0461] tibia (65); [0462] hip joint/axis (66); [0463] knee joint/axis (67); [0464] ankle joint/axis (68); [0465] Centre of Mass, CoM (69); [0466] a torso inclination angle θ with respect to vertical, where a substantially upright posture with a vertical torso gives an inclination angle θ˜0° [0467] a hip angle β, subtending the interior angle between the axis of the patient's femur/thigh and their torso/trunk, where a thigh/femur orientation substantially orthogonal to the torso gives a hip angle of β˜90°; [0468] a knee angle λ, denoting the interior angle between thigh/femur and the shin/tibia—where a shin/tibia orientation substantially orthogonal to the thigh/femur, gives a knee angle λ˜90°, and [0469] a shin angle Ω with respect to vertical, where a substantially vertical shin/tibia gives a shin angle Ω˜0°.

[0470] It will be appreciated that the various dimensions and parameters of each of these features will vary with the patient. The patient in the figures is shown for example only.

[0471] FIGS. 2-5 show perspective views of a patient moving device (1) according to two different embodiments. FIGS. 2-3 show a first embodiment and FIGS. 4-5 show a second embodiment. The first and second embodiments differ in dimensional and some aspects but otherwise include similar components and function similarly. Like parts are similarly numbered for both embodiments. The following description is thus made with respect to both embodiments.

[0472] The patient moving device (1) includes a terrain-engaging mobile chassis (3) with wheels (26, 27) attached thereto, facilitating movement of the entire PMD (1) over the terrain (2). The rear wheels (26) are rotating castors while the front wheels are larger and include a brake mechanism in the form of wheel locks (33).

[0473] Two footrests (35) are included on the chassis (3) for the patient (25) to position their feet thereon. The two footrests (35) may be provided by two separate platforms, or by left and right sides of a single platform and may optionally be adjustable.

[0474] A pair of knee rests (37) are included and formed to engage with, and at least partially support, a patient's anterior knee surfaces during patient handling. The knee rests (37) are movable relative to the chassis (3).

[0475] A moveable patient-support is provided in the form of chest pad (5) formed to engage with, and at least partially support, a patient's anterior torso (63) during patient handling.

[0476] Movement and operation of the patient moving device (1) during patient handling is performed by a carer (12) via an operating handle (6).

[0477] A reorientation mechanism (4) is coupled to the chest pad (5), operating handle (6) and chassis (3). The reorientation mechanism (4) includes a multi-bar linkage (10) pivotally connected to the chassis (3) and pivotally connected to the handle (6) and chest pad (5).

[0478] The chest pad (5) is connected to a primary pivot (17) via an upper frame (14) of the reorientation mechanism (4). The primary pivot (17) is rotatable about a primary pivot axis (20). The chest pad (5), upper frame (14) and connected operating handle (6) are thus all pivotable about the primary pivot axis (20). The reorientation mechanism (4) is thus coupled to the patient-support (5), primary pivot (17) and chassis (3). The handle (6) is configured to rotate about the primary pivot axis (20).

[0479] The chest pad (5) may be cushioned or compliant for comfort, and maybe contoured to cradle and aid in centring the patient's torso on the chest pad (5).

[0480] A patient securement strap (56) is provided in the form of a back strap which is connected to two straps (18) with strap hooks (57) that can be hooked onto strap securement points (58) on the handle (6). The patient securement strap (56) is configured to form a loop around at least the patient's posterior torso in use.

[0481] The multi-bar linkage (10) is a 4-bar linkage including coupler link (15), first support link (7), second support link (9) with the fourth bar formed by a portion of the chassis (3).

[0482] The chest pad (5) is rigidly connected to the coupler link (15) which forms part of the upper frame (14). The primary pivot (17) is formed at one end of the coupler link (15) to which one end of the first support link (7) is pivotably connected. The handle (6) may be coupled to the patient support (5) via the coupler link (15) or via upper frame (14).

[0483] The first support link (7) is connected to coupler link (15) at one end and to the chassis (3) at an opposing end which forms a second pivot (11) rotatable about a secondary pivot axis (21). The secondary pivot axis (21) is located eccentrically from the primary pivot axis (20).

[0484] The second support link (9) is connected at one end to the coupler link (15) at a fourth pivot (19) and at an opposing end to the chassis (3). The second support link (9) is rotatable relative to the chassis (3) via a third pivot (13). The second, third, first, and fourth pivots (11), (13), (17), (19) have parallel pivot axes.

[0485] The knee rests (37) are formed from two main parts, including a mounting bracket (41) and knee pads (28). The knee pads (28) are cushioned for comfort. The knee rests (37) are both attached to the first link (7) by bracket (41). The knee pads (28) each include a contact surface (40) and lateral knee restraints (42). The knee rests (37) are thus configured to cradle and locate the patient's knees, with the contact surfaces (40) and lateral knee restraints (42) constraining the knees on three sides. The knee rests (37) may also be provided with one or more straps (not shown) for securing a patient's knees or legs in place. This may be necessary for transporting a patient who, for example, experiences leg spasms.

[0486] The knee rests (37) are pivotable about a tertiary pivot axis (22) located on the chassis. In the embodiments shown in FIGS. 2-5 the tertiary axis is coaxial with the secondary pivot axis (21). The knee rests (37) are connected to the primary pivot (17) via first support link (7) and thus pivotable about the secondary (21) and tertiary (22) pivot axis to move with the first support link (7). The knee rests are thus movable (and pivotable) relative to the chassis (3). The at least one knee rests (37) are pivotable about the tertiary pivot axis (22) in conjunction with the primary pivot (17).

[0487] As shown in FIG. 5, the knee rests (37) are attached to the bracket (41) by two bolts (30) passing through one of three slots (32) on the bracket (41). The knee pads (28) may be moved laterally away or towards from the 4-bar linkage (10) to respectively widen or narrow the gap between the knee pads (28). Once adjusted, nuts (not shown) can be tightened on the bolts (30) to maintain the knee pads (28) in position.

[0488] The knee pads (28) can be adjusted vertically by unbolting the pads (28) from brackets (41) and moving the knee pads (28) up/down such that the bolts (30) align with one of the other two slots (32) available. Thus, the knee pads (28) may be adjustable laterally and vertically in the loading/unloading position prior to patient handling.

[0489] Operation to reorientate the reorientation mechanism (4) during patient handling to raise or lower the seated patient (25) between an initial sitting position and a transport position re-orientates the patient support (5) between a patient loading/unloading configuration and a patient transport configuration.

[0490] The patient support (5) is movable relative to the chassis (3) by rotation of the primary pivot (17) and the secondary pivot (11). The reorientation mechanism (4) is also configured such that rotation of the operating handle (6) causes rotation of the patient support (5) relative to the knee rests (37).

[0491] Upper and lower, spaced-apart horizontal crossbars (47), (48) are provided on the carer handle (6), the bars (47), (48) being parallel to the axes of the pivots (11), (13), (17), (19) in the four-bar linkage. In the patient loading/unloading configuration, both upper and lower crossbars (47), (48) are positioned above the chassis (3), behind a front of the chassis (3), with at least the upper crossbar (47) being rear of the lower crossbar (48) and rear of the knee-rests (37).

[0492] The chest pad (5), the operating handle (6), frame (14) and the coupler link (15) are in fixed relation to each other such that movement of the operating handle (6) causes a corresponding movement of the coupler link (15), frame (14) and chest pad (5).

[0493] In the embodiment shown in FIGS. 2-5, the two footrests (35) are provided on either side of the four-bar linkage (10) such that when the patient's feet (36) are positioned on the footrests (35), the second and third pivots (11), (13) are adjacent the patient's feet (36) or ankles and the first and second support links (7), (9) are between their legs. That is, the first and second support links (7), (9) are located and move in a sagittal plane that is between the two footrests (35). This configuration provides a more compact device than an embodiment where the linkage (10) is provided laterally on the patient moving device (1).

[0494] The rear-facing (patient-facing) knee-rests (37) are provided towards the middle of the chassis (3), substantially above the second pivot (11) and are attached to the first support link (7). The knee-rests (37) may contact and support a patient's knees while the patient is positioned in the patient moving device (1). The patient's knee joint pivot axis (38) may be directly above their ankle joint in the loading position. The knee-rests 37 may be cushioned for comfort and maybe contoured to cradle and locate the knees. Optionally the knee-rests may be provided with one or more straps for securing a patient's knees or legs in place. This may be necessary for transporting a patient who, for example, experiences leg spasms.

[0495] Patient handles (43) are provided for a patient (25) to hold during the transportation/transfer process. The patient handle (43) is rigidly connected to the carer handle (6) such that it moves with the carer handle (6) and chest pad (5) and is positioned to enable the patient (25) to reach it and grip it with slightly bent elbows.

[0496] A patient-support sliding adjustment member (54) is attached to the moveable patient-support (5) and can slide back and forth in the horizontal (when in the load/unload position) through a corresponding mounting aperture in upper frame (14). The adjustment member (54) is fixed/locked prior to patient reorientation of the device by the coupler link locking pin (55), is located through an aperture in the upper frame (14) and into a locking pin hole (53) in the patient-support sliding adjustment member (54). The chest pad (5) is thus horizontally adjustable to accommodate patients of varying dimensions.

[0497] The operating handle (6) is rigidly mounted to the upper frame (14) and thus as the handle (6) rotates about the primary pivot axis (20) the chest pad (5) also rotates about the primary pivot axis (20).

[0498] The rear wheels (26) are connected to the chassis (3) via two legs (29) that can be splayed apart (as indicated by arrows “S”), about front pivots (31), to increase the wheelbase of the chassis (3) or accommodate chair legs where necessary.

[0499] A foot activated rocker lever (24) is provided adjacent the front wheels (27). The carer (12) may push down on one side of the lever (24) which acts to force the legs (29) to rotate about front pivots (31) to splay the rear wheels (26) apart. Pressing down on the opposing side of the lever (24) forces the legs (29) to rotate in the opposite direction about front pivots (31) to return the rear wheels (26) and legs (29) to the ‘un-splayed’ original position. The carer (12) may thus quickly and easily splay or un-splay the wheels as required merely by pressing their foot on one side or the other of the lever (24).

[0500] The device 1 includes a position locking means (59) to fix the coupling link (15) in position at any desirable angle. In this embodiment, the position locking means (59) is shown in the form of a telescoping strut that is connected at a pivot (60) on the coupler link (15) and a pivot (61) on the chassis (3). The position locking means (59) is unlocked by compressing the locking lever (62) mounted on the crossbar (47). Unlocking the position locking means (59) allows the linkage system to move. When the locking lever (62) is released the four-bar linkage system is locked its current position. This allows the position of the movable chest pad (5) to be held constant during loading procedure, as well as, the patient's (25) preferred transfer position to be selected.

[0501] The position locking means (59) may be of mechanical, pneumatic, hydraulic or electrical type.

[0502] It should be noted that FIG. 3 shows an alternate perspective view of the patient moving device (1) with the knee-rests (37) removed to show the 4-bar linkage (10) more clearly.

[0503] It will be appreciated that the patient (25) may not have the strength or mobility to place their hands and arms in a comfortable position and avoid their arms interfering with patient handling. Thus, the embodiment of FIGS. 2-3 includes a pair of armrest brackets (16) upon which an armrest (not shown) is attached. The armrest is for the patient (25) to rest their arms upon in an overlapping or folded arrangement during patient handling, thereby keeping their arms comfortably and safely constrained.

[0504] The patient reorientation movement will now be described with respect to FIG. 8, which shows the reorientation of the reorientation mechanism during patient handling to raise or lower a seated patient between an initial sitting position and a transport position to thus re-orientate the patient support between a patient loading/unloading configuration and a patient transport configuration.

[0505] With reference to FIGS. 8a, 8b and 8c, the patient moving device (1) is movable from a patient loading/unloading configuration (FIG. 8a) to a patient transport configuration (FIG. 8c), via an intermediate position (FIG. 8b) by pulling the operating handle (6) forward and down.

[0506] The patient moving device (1) is movable in reverse from the patient transport configuration (FIG. 8c) back to the patient loading/unloading configuration (FIG. 8a) by lifting the operating handle (6) up and rearwards.

[0507] The patient moving device (1) is initially placed directly in front of the patient (25) to be transported in the patient load/unload configuration (FIG. 8a).

[0508] As the patient moving device (1) is placed directly in front of the patient (25) to be transported, the chest pad (5) is directly in front of the patient's torso or chest. The chest pad (5) can be adjusted on a horizontal plane by the carer (12) unlocking the coupler link locking pin (55) and sliding the patient-support sliding adjustment member (54) by pushing using handle (8) with one hand while the other hand holds bracing handle (23). The adjustment handle (8) is pushed toward the patient until the patient-support surface (39) contacts the front of the torso of the patient (25). As shown in FIG. 8a, a patient does not need to lean forward significantly to contact the patient-support surface (39) of the chest pad (5) allowing the patient (25) to be loaded and unloaded into their original sitting position without requiring the patient (25) to lean or to be moved. The form of the movable patient-support may be customised for people of varying sizes, or with differing physical conditions.

[0509] The patient securement strap (56) may be fitted around the rear of the patient in order to secure the patient against the patient-support (5) and to provide security against the patient falling. The patient securement strap (56) has an adjustable length and thus can be tightened or loosened about the patient (25) to ensure an optimum fit.

[0510] The patient securement strap (56) is fitted around the back of the patient (25) and the strap hooks (57) are connected to the strap securement points (58) on the operating handle (6). The patient securement strap (56) has the capability to be tightened about the patient (25) to ensure a snug fit.

[0511] As shown in FIG. 8, during use, as the carer rotates the operating handle (6) forward, the patient (25) is lifted from their seat and ‘rolls’ forward, their weight being progressively transferred forward to the patient moving device (1) and the patient's knee joints (38) acting as a pivot point.

[0512] The carer (not shown) continues to push the operating handle (6) down until the device (1) reaches the transport configuration shown in FIG. 8c. In the embodiment shown in FIG. 8, from the patient loading/unloading position, the first support link (7) moves through an angle of 25 degrees relative to the chassis, and the coupler link (15) moves through an angle of 65 degrees relative to the first link (7). The coupler link (15) (and thereby, the frame (14) and movable patient-support (5)) moves through an angle of about 90 degrees relative to the chassis (3), from the patient loading/unloading configuration to the patient transport configuration. Therefore, in the transport configuration (FIG. 8c), the torso (63) of the patient (25) is rotated forward about 90 degrees from vertical to be approximately horizontal in the transport position with most of the patient's weight carried through the patient-support (5).

[0513] Some patients may prefer a slightly inclined position, therefore, in other embodiments, the movable chest pad (5) may move through a larger or smaller angular range. However, for comfort reasons, it is desirable that the patient's torso is rotated forward at an angle of about 60 to about 80 degrees, nominally 70 degrees from vertical. However, the patient's torso may be rotated more than 80 degrees or less than 60 degrees, depending on the preferences of the patient.

[0514] In the transport configuration, both crossbars (47), (48) on the operating handle (6) are forward of the chassis (3). The patient moving device (1) may be lockable in the transport configuration and/or the patient loading/unloading configuration using the position locking means (59).

[0515] Once in the transport configuration shown in FIG. 8c, the patient can then be transported by the carer (12). To transport the patient (25), the carer (12) unlocks the front wheels (27) and when appropriate, retracts the splayed legs (29) by pressing on lever (24).

[0516] The wheels (26), (27) on the chassis (3) then allow the carer (12) to manoeuvre the device along the floor to the destination. In the transport position, if correctly loaded, the patient's centre of mass should not be forward of the front of the chassis (3) to avoid causing the device (1) to tip forward.

[0517] To unload a patient (25) from the patient moving device (1), the above-described steps are reversed. The chassis legs (29) are optionally splayed during approach, to avoid clashing with the target seating surface, the chassis (3) is secured relative to the floor by locking the front wheels (27), or otherwise securing the chassis (3). The carer (12) then pulls the operating handle (6) upwards and towards his or herself, and then rearwards and upwards, using either or both of the cross bars (47), (48), as needed. A stop may limit rearward rotation once the patient loading/unloading position is reached, the stops optionally being adjustable to alter the load/unload position (FIG. 8a) of the patient moving device (1).

[0518] The patient (25) is subsequently moved back into contact with the new seating surface and into a seated position. The patient moving device (1) may be optionally rotated further rearwards than shown to push the patient (25) into an upright seated position so that they do not need to use their own strength to disengage from the patient moving device (1).

[0519] The patient moving device (1) is suitable for numerous applications such as moving a physically impaired patient between a chair, a bed, a toilet, a wheelchair, car and the like. The compact design of the patient moving device (1), with the four-bar mechanism being centrally located and rear of the knee rests (37), and the operating handle (6) being over the wheelbase of the device in the patient load/unload position, enables the device to be suitable for use in a range of locations where larger devices may be impractical.

[0520] As the knee-rests (37) are connected to the first support link (7) which is in turn pivotable about the first (20) and second pivot axes (21), the patient's knee joints (38) move forward during the transfer process. The patient's knee should move to approximately vertically above the front of the patient's foot (36) with the knee joints (38) approximately 60 mm rearwards. This feature ensures that the hip angle, β, is held relatively constant throughout the transfer process, thus avoiding extra hip flexion from the body position of the initial loading arrangement in FIG. 8a.

[0521] In the embodiment shown in FIG. 8a, the patient loading/unloading position, the first pivot (17) is above and substantially vertically aligned with the fourth pivot (19), such that the coupler link (15) of the four-bar linkage (10) is substantially vertical. As the device transitions to the transport position (FIG. 8c), the first pivot (17) moves forward and down along an arc, until the first pivot (17) is forward of and generally horizontally aligned with the fourth pivot (19).

[0522] The relative positions of the first (17) and fourth (19) pivots will change if different patient loading/unloading positions or patient transport positions are desired. For example, for a transport position where the patient's torso is slightly inclined, the coupler link (15) may form an angle with respect to horizontal of about 10 degrees to about 20 degrees, preferably about 10 degrees to about 15 degrees. In an alternative embodiment, the coupler link (15) may form an angle with respect to horizontal of about 17.5-22.5 degrees, preferably about 20 degrees.

[0523] The geometry of the first and second support links (7), (9) and the coupler link (15) are selected such that the resultant movement of the moveable patient-support is along a curvilinear path which approximately optimises vertical movement of the centre of mass of the patient being transported between the transport position to minimise the mechanical work required to move the device between the two positions while maximising patient comfort. The centre of mass (not shown) of the patient (25) follows a shallow non-circular arc between the loading/unloading position and the transport position, with the highest point of the centre of mass being between the patient loading/unloading position and the patient transport position.

[0524] The device utilises mechanical advantage to enable a carer to transition a patient on and off the device and therefore transfer them between two locations using a level of force that is acceptable by workplace safety standards.

[0525] It will be apparent that patients of different heights will have different centres of mass. The patient moving device (1) may be optimised for patients of a specified height range, and/or may come in various sizes.

[0526] The length of the distance between the movable chest pad (5) and the first pivot (17) will be a function of the height of the patient and this distance may be adjustable. For example, the moveable chest pad (5) may be slidable relative to the coupler link (15), or along the handle lever (41), or adjustable in height.

[0527] The movement path of the chest pad (5), handle (6) and knee-rests (37) is therefore determined by the geometry of the four-bar mechanism and the position of the chest pad (5) and handle (6) on the coupler link (15).

[0528] In the embodiments shown in FIGS. 2-5, the second and third pivots (11), (13) are provided on the chassis (3) at the same height, with the second pivot (11) being about 80 millimetres to the rear of the third pivot (13). However, alternatively the second and third pivots (11), (13) may be at different heights. The first and fourth pivots (17), (19) are provided on the coupler link (15), with the fourth pivot (19) provided adjacent to a first end of the coupler link (15) and the first pivot (17) spaced about 65 millimetres from the fourth pivot (19).

[0529] The first and second support links (7), (9) may be straight links or may be otherwise shaped, for example, to improve the ergonomics, compactness, or safety of the patient moving device (1).

[0530] In the embodiment shown in FIGS. 4-5 and 8, the first link has a straight portion joined to the secondary pivot (11) and an angled upper portion connected to the primary pivot (17). The first link (7) may thus be considered ‘L-shaped’. The first link (7) straight portion is rear of the second link (9). A rigidly connected angled bracket at an upper end of the first link (7) facilitates the connection to the coupler link (15). This angled link shape moves the first link (7) away from the patient while accommodating movement of the second link (9).

[0531] In the embodiment shown in FIGS. 2-5, the chest pad (5) is mounted on a patient-support sliding adjustment member (54) that is telescopically adjustable relative to the coupler link (15) to adjust the position of the movable patient-support (5) relative to the first pivot (17).

[0532] Alternatively one or more of the links (7), (9), (15) or the positions of one or more of the pivots (11), (13), (17), (19), and/or the position of the movable chest pad (5) on the coupler link (15) may be adjustable to better fit the patient moving device (1) to a range of people.

[0533] The mechanical advantage that the device provides for a patient of a given height can be tuned by relative movement of the second pivot (11) forwards or away from the knee-rests (37), or fore-aft adjustment of the knee-rests (37).

[0534] Some embodiments of the device may be made from light-weight metal alloys and/or composite materials to improve the portability of the device. Optionally, the device may be foldable or able to be disassembled easily into smaller components for transport.

[0535] FIG. 9 shows a schematic diagram of the patient reorientation between an initial sitting position (patient (25) and carer (12) indicated in solid lines) and a transport position (patient (25′) carer (12′) indicated in dashed lines). Components shown in the transport position are denoted by the same reference numeral with an appended apostrophe “'” indicated having moved position from the initial sitting position.

[0536] The curvilinear path travelled by the patient CoM (69) is represented by arc (50). Similarly, the curvilinear path travelled by the handle (6) is represented by arc (51).

[0537] FIG. 10 shows a schematic representation of the mechanics of a seated patient being moved by the prior art device of U.S. Pat. No. 8,832,874 by Alexander with a single pivot axis (52) approximately through the knee joint (38). Knee rests (67) are provided but are fixed to the chassis (3), in contrast to the movable knee-rests (37) of preferred embodiments of the present invention, e.g. as shown in FIGS. 2-9.

[0538] The patient (25) is shown being tipped forward to position 25′ by rotating about the pivot axis (52). The hip flexion angle (β) is maintained at about a constant 87-90° during the reorientation and results in the knee angle changing from about λ˜90° to about 155°. However, a potentially adverse impact for many patients by such a configuration is a deleterious stretching of their hamstrings as their knee joint angle λ increases during lifting/rotation in order to reach the torso inclination θ of around 70°. It has been found that a λ˜155° is a difficult or uncomfortable knee angle for many elderly or infirmed patients, when their torso is orientated around 70°, due to the hamstring stretching involved.

[0539] Thus, as described above, preferred embodiments of the present invention, such as shown in FIGS. 2-9 aim to address this problem by utilising moving knee rests (37). The knee rests (37) move in correlation with, or at least move proximal to, the movement of the primary pivot (17). In the embodiments of FIGS. 1-9 this movement is achieved by connecting the knee rests (37) to the primary pivot for common rotation about the secondary pivot (11).

[0540] In the above described embodiments, the knee-rest (37) is directly attached to the reorientation mechanism (4) at the primary pivot (17) at the distal end of the first support link (7). However, the knee-rests (37) may be attached to the chassis (3) (or other convenient portions of the patient moving device (1)) by any convenient means including spring-biased levers, linear and/or curved tracks, cushioned/semi-elastic pads and so forth.

[0541] FIGS. 11A and 11B thus show two alternative configurations for attaching the knee-rests (37) to the chassis (3).

[0542] FIG. 11A shows a configuration with the knee-rests (37) attached near to the distal end of the second support link (9). FIG. 11B shows a configuration with the knee-rests (37) attached to a distal end of a knee-pad mounting link (44), and pivotally attached at the other end to the chassis (3) at pivot (45) to pivot about tertiary pivot axis (22) located proximal or adjacent to the secondary pivot axis (21). A resilient means in the form of spring (46) attached between the knee-rest mounting link (44) and the chassis (3) acts to provide a restorative resistance force against the force applied by a patient's knees during patient handling. In both the configurations shown in FIGS. 11A and 11B, the knee rests (37) travel in a path that substantially correlates, is similar, or is proximal to the path travelled by the primary pivot (17).

[0543] It can be thus seen that each of the preceding embodiments, as shown in FIGS. 1-9 and 11 provide an advantageous means of addressing the prior art issue of excessive hamstring extension (as shown in FIG. 10), by the incorporation of moving knee rests (37). In the embodiments shown in FIGS. 1-9, 11 this movability is achieved by attaching the knee rests (37) to the chassis (3) for rotation about a tertiary pivot axis (22) (located eccentrically from said primary pivot axis (20)) allowing differential movement between different bodily portions of the patient (25) during patient handling. In FIGS. 1-9 the tertiary pivot axis (22) is coaxial with the second pivot axis (21) while in FIG. 11A the tertiary pivot axis (22) is located at fourth pivot (19) and in FIG. 11B is located between second (11) and (fourth (19) pivots.

[0544] Moreover, although it is highly convenient and effective to attach the knee rests (37) directly to the primary pivot (17), if can be seen that the alternative exemplary embodiments in FIGS. 11A and 11B allow alternative knee rest (37) attachments configuration to provide similar patient handling movements.

[0545] The effect of including a pivot axis (22) for the knee-rests (37) to move/pivot about is to allow the connected reorientation mechanism (4) and attached chest pad (5) to pivot together about the connection with the chassis (3). Consequently, this allows the patient's knees, that are contacting the knee-rest (37), to also pivot forwards towards the carer (12) about the tertiary pivot axis (22) as the patient (25) is lifted from the initial sitting position during patient handling. This motion mimics the natural, uncompromised movements performed by able-bodied humans rising from a sitting position.

[0546] As discussed, the use of a primary pivot (17) by which the patient-support (5) pivots about the primary pivot axis (20) enables the use of a patient-support (5) such as the chest pad (5) to be secured rigidly to the reorientation mechanism (4). The patient torso (63) and patient-support (5) are thus maintained in a generally constant spatial-positioning relative to each other as the torso (63) of the patient (25) engaged with the fixed patient-support (5) also pivots about the primary pivot axis (20).

[0547] As shown in FIG. 12, it will be apparent however, that if the chest pad (5) were configured to pivot solely about a single primary pivot axis (20) positioned eccentrically from the knee joint pivot axis (38), different bodily parts of the patient (25) would experience a differential movement during patient handling as the patient (25) also pivots about their knee joint (38). The differential movement will vary with the magnitude and direction of eccentricity and may lead to the adverse consequence shown in FIG. 12 of the insecurity of the patient (25) losing intimate engagement with the chest pad (25) and the associated discomfort.

[0548] It is helpful in the analysis of dynamic mechanic systems to resolve the various movements and elements to their basic effective components. To this end, it will be understood the mass of the patient being supported by the patient support can be considered mechanically equivalent to the same mass concentrated at a single point, i.e. the patient's centre of mass.

[0549] It has been determined that the variations in position of the centre of mass, in the sagittal plane, from the full size and weight spectrum of patient's (25) able to use the patient moving device (1) lie within the area of a 200 mm sided square (a centre of mass aggregation region (70)), i.e. +/−100 mm from a centre-point (69) of the square. Moreover, it has further been determined that said a centre of mass aggregation region geometric centre-point (69) would be positioned 340 mm horizontally and 270 mm vertically above (or a distance r=434 mm at an angle of Ø=38.5° from) said primary pivot (17) for a given patient (25) using the patient moving device (1). As previously referenced, the nomenclature used herein designates the term ‘centre-of-mass’, ‘Centre-of-Mass’, as referring to, or relating to the centre of mass of any given patient, while the part-capitalized abbreviation ‘CoM’ specifically relates to said centre of mass aggregation region geometric centre-point.

[0550] It can also be seen that the movement of any notional point on the patient support (5), in direct contact with the torso (63) of a patient (25), will trace the same path during patient handling as an adjacent point on a patient (25) in contact with that notional point on the patient support (15). Given the distance of the patient support (5) from the primary pivot (17) may be adjusted to accommodate different sized patients (25), it follows the reorientation mechanism (4) could be adjusted to position the contact surface (39) of patient support (5) at the same position of the centre-point (69).

[0551] Thus, (as represented in FIG. 14) given the patient support (5) is rigidly coupled to the primary pivot (17), and is engaged with a patient's anterior torso throughout patient handling, it follows that said centre-point (69) is: [0552] a representative Centre of Mass (CoM) (69) of any patient, and [0553] functionally equivalent to being rigidly connected by said reorientation mechanism (4) to said primary pivot (17) by a linkage of 434 mm orientated at 38.5° above horizontal for a seated patient (25) with an upright, substantially vertical torso (63) with an inclination angle θ˜0° and knees engaged with knee rests (37) such that the patient's knee-joint pivot axis (38) is co-axial with the primary pivot (17).

[0554] This allows the trajectory path (50) of the CoM (69) to provide a reliable and accurate representative, proxy or surrogate for the trajectory path of all patients (25) during patient handling.

[0555] FIGS. 15-18 illustrate the functionality of a patient securement strap (56) used to hold the anterior surface of a patient's torso (63) in close engagement with the chest-pad (5) during the patient handling. The patient securement strap (56) assists in ensuring intimate engagement of the patients' hips and torso (63) with the chest pad (5) during patient handling between the initial sitting position and the transport position.

[0556] The patient securement strap (56) enables the patient moving device (1) to be used for patients with insufficient upper body strength or who are otherwise unable to maintain a grasp a device during patient handling, in contrast to prior art devices.

[0557] The patient securement strap (56) includes an adjustable loop extending from the patient moving device (1), around the patient's posterior torso. The patient securement strap (56) includes two adjustable-length link straps (18) with hooks (57) for connecting the strap (56) to the strap securement points (58) on the handle (6). The link straps (18) include force adjustment means (not shown) to adjust the length thereof. The patient securement strap (56) can thus be tightened about the patient (25) to ensure a snug fit. The adjustable-length link straps (18) also enable the patient securement strap (56) to accommodate different sized patients.

[0558] In use, prior to patient handling, the patient securement strap (56) is fitted around the rear of the patient (25). This position is shown in FIGS. 15A, 17A and 18A. The straps (18) are then tightened by reducing their length in order to secure the patient (25) against the patient-support (5) to prevent, or at least minimise, movement of the patient (25) relative to the patient support (5), thus providing security against the patient (25) falling during the reorientation.

[0559] FIGS. 15B, 17B and 18B show the patient moving device (1) in the transport position with the patient (25) rotated through 70°. The patient securement strap (56) maintains the patient (25) in a stable position against the chest pad (5) and thus maintains a constant patient hip angle β throughout the reorientation movement.

[0560] FIG. 16, in contrast to the embodiment of FIGS. 15, 17 and 18, shows the result of attempting to reorientate the patient (25) without utilising such a securement strap (56). The patient (25) may slip after lifting commences or fail to maintain a sufficiently secure engagement to retain contact with the patient support (5) as it begins moving upwards from the initial sitting position towards the transport position. As the patient increasingly slouches away from the moving patient support (5) the hips (and the hip joint axis (66) of the patient (25) becomes increasingly disengaged from the patient support (5). Moreover, this results in the hip angle β being reduced, causing discomfort for the patient (25) and reducing stability of the patient (25) and supporting patient moving device (1) during transport.

[0561] In the embodiment shown in FIGS. 17A and 17B the securement strap (56) has a securement point (58) located on the operating handle (6) at a position such that the link straps (18) subtend an angle of ϕ˜60° (+/−7.5°) from vertically upright with the patient support (5) orientated in the patient loading configuration.

[0562] An alternative embodiment is shown in FIGS. 18A and 18B with the securement strap (56) connected to a securement point (58) located on the chest pad (5) at a position such that the link straps (18) subtend an angle of ϕ˜60° (+/−7.5°) from vertically upright with the patient support (5) orientated in the patient loading configuration.

[0563] In both embodiments the strap (56) in use acts to ensure the patient's torso (63) is maintained in engagement with the chest pad (5) as the handle (6) is rotated.

[0564] During the patient handling procedure shown from FIG. 8A to FIG. 8B the geometry of the relative movement between the patient securement strap (56), the strap securement points (58) and the chest pad (5) causes the patient securement strap (56) to further tighten as the patient's weight is transferred on to chest pad (5) and hence better secure the patient (25).

[0565] The relative geometry between the patient securement strap (56), strap securement points (58) and the moveable patient-support (5) can be selected to cause the patient securement strap (56) to further tighten about the patient (25) relative to the chest pad (5) due to the process of lifting the patient (25) as follows.

[0566] After the patient is secured and patient handling is commenced, the reorientation mechanism (4) rotates through a small angle until the patient (25) starts to be raised from their initial sitting position. During this initial rotation while the patient (25) remains seated, the innate elasticity of the human torso causes the lower portion of the rotating patient support (5) to further compress the patient's abdomen region below the ribs, whilst the greater rigidity of the ribs and sternum region resists such deformation to a greater extent. Thus, the patient support (5) effectively becomes partially dovetailed or ‘keyed’ into the region under the ribs and thus further ameliorates the propensity for the patient to slip between patient securement strap (56) and patient support (25) as patient handling commences.

[0567] This tightening of the strap and pressing of the patient toward the chest pad (5) is represented in FIGS. 17B and 18B which show the reduction in the distance (d) between the chest pad and strap (56) as the handle (6) is rotated. Similarly, this movement causes the angle ϕ of the link straps (18) with respect to vertical to decrease as shown by the difference in ϕ between FIGS. 17A and 17B and between FIGS. 18A and 18B.

[0568] Thus, the configuration of the patient securement strap (56) ensures the patient's hip angle β is maintained between 80-110°, and preferably between 87-90° during patient handling. Preventing the hip angle β from reducing has been found to be important for patient comfort during handling.

[0569] As shown more clearly in FIGS. 15, 17 and 18, the patient securement strap (56) also provides the ability to assist a slumped seated patient in raising their torso upright. It will also be readily apparent that by appropriately tightening the patient securement strap to securely restrain the patient (25) against the patient-support (5) during patient handling, any risk of the patient slipping downwards or laterally during patient handling is greatly minimised.

[0570] Simple prior art straps or slings used to assist in patient handling also typically pass around a patient's posterior torso and, in some cases, pass under the seated patient's hips/thighs. Notwithstanding the difficulty for both a carer and a non-weight-bearing patient in positioning a strap underneath the patient (as discussed previously), it is recognised that such straps/slings typically provide only limited ability to maneuverer a patient in directions non-aligned with direction of the applied force in the strap/sling without slippage.

[0571] In contrast, the combination of the patient support (5) and the patient securement strap (56) allows the patient's torso (63) to be secured therebetween, with the compressive forces being distributed between the opposing sides of the torso (63). This configuration allows a higher force to be applied to a greater area of the torso (63) with increased frictional resistance to slippage of the patient securement strap (56) upwards towards the patient's armpits during lifting.

[0572] A person moving device (100) according to an alternative embodiment is shown in FIG. 19. The person moving device (100) has an alternative reorientation mechanism (80) to the reorientation mechanism (4) shown in the preceding embodiments. FIG. 19A depicts the patient moving device (100) in the patient loading/unloading configuration at the start or end of patient handling, while FIG. 19B shows the same patient moving device (100) in the transport position.

[0573] In contrast to the use of a 4-bar linkage reorientation mechanism (4) of the embodiments of FIGS. 2-9, the embodiment of FIG. 19 incorporates a geared reorientation mechanism (80) including a slidable carriage (81) coupled to a curved track (82). The primary pivot (17) is coupled to carriage (81) and configured to slide along the curved track (82).

[0574] It can be seen that despite the visual disparity between the reorientation mechanisms (4, 80) in the person moving devices (1, 100), there is a high degree of equivalence between the functional role of the individual linkages L (7), P (9), S (15) and Q (3) of the 4-bar linkage reorientation mechanism (4) and that of the geared reorientation mechanism (80). The linkages L (7), P (9), S (15) and Q (3) of the 4-bar linkage reorientation mechanism (4) will now be compared with the alternative reorientation mechanism (80).

[0575] The equivalent of first support linkage L is provided by the curved track (82). The curved track (82) is attached at one end to the chassis (3) and shaped to correspond to the arc sector swept by the rotation of linkage L about the secondary axis (21) of the preceding embodiments. In the embodiment, the secondary pivot axis (21) is a virtual pivot, located adjacent the location of the patient's ankles (68) on the chassis (3) at the geometric centre (83) of the curved track;

[0576] The second support linkage P equivalent is provided by the geared mechanism (80) which includes quadrant gears (84) engaging with a toothed gear track (85) on a complimentary portion of the curved track (82), providing the relative rotational input equivalent to the effect of the second support linkage P.

[0577] The equivalent of coupler link S is provided by the carriage (81) slidably mounted on the track (82) with a pivotable ‘coupler’ portion (86) rotatably attached to the gears (84) and pivotable about a primary pivot (17). The coupler portion thus forms a functional equivalent to the primary pivot (17) (and primary pivot axis (20)) and coupler link S. The patient support (5) is coupled directly (or indirectly via a suitable mounting, housing or the like) to the pivotable coupler portion (86) and, for example, may be manually rotatable for patient handling by a carer (not shown) via an attached operating handle (6).

[0578] A ground link Q equivalent is provided by the chassis (3) as a ground link between the virtual secondary pivot axis (21) and the attachment point (87) of the curved track to the chassis (3).

[0579] A further alternative embodiment is shown in FIG. 20 including a person moving device (200) with a modified reorientation mechanism (4). FIG. 20 depicts a patient moving device (200) in the patient loading/unloading configuration at the start or end of patient handling, while FIG. 20B shows the same patient moving device (200) in the transport position.

[0580] In this embodiment, instead of replacing the purely mechanical 4-bar linkage reorientation mechanism (4) with a different design, an electrical drive (88) is used as an additional part of the reorientation mechanism (4) to substitute (or supplement) for the manually input motive power provided in the prior embodiments by the carer (12) rotating handle (6).

[0581] The electrical drive (88) is provided in the form of a linear drive attached between the chassis (3) and a portion of upper frame (14) which includes the coupler link S. The electrical drive (88) is attached via a drive pivot (89) to the frame (14) and is thus constrained to operate eccentrically to the primary pivot axis (20) and the secondary pivot axis (21), causing the patient support (5) to rotate about the primary pivot axis (20). The electrical drive (88) may be operated by the carer (12). In some embodiments the carer (12) or the patient (25) may control the drive (88) via remote or wireless control or directly by controls (not shown) mounted on the patient moving device (200).

[0582] The person moving device (200) is shown with a shortened handle (6) (omitting the crossbars (47)) in comparison to the handle (6) of preceding embodiments. The handle (6) may no longer be required to operate as a ‘handle’ as such for rotating reorientation mechanism (4) but may still be required as it includes the securement points (58) for the patient securement strap (56).

[0583] Another alternative embodiment (not shown) may include a reorientation mechanism (4) with a rotational electrical drive replacing or coupled to one or more of the pivotal connections (11, 13, 17, 19) of the 4-bar linkage (10) to provide rotational motive power. This motive power may supplement or completely replace the need for manual input from a carer to move the patient from the initial sitting position to the transport position.

[0584] As illustrated by these exemplary configurations, there are numerous possible reorientation mechanisms, of which these are just a few illustrations.

[0585] As discussed previously, the position of the effective pivot point of the movement of the patient (25) during patient handling is highly influential on: [0586] the input force required by the carer (12) to raise the patient (25) through the vertical component of its movement trajectory; [0587] the comfort and ergonomic compatibility of the movement on the patient (25), and [0588] the ability of the relative movements imposed by the patient moving device (1, 100, 200) by any rotations about a pivot point are compatible and sympathetic to the natural movements of a human body. The inclusion of pivot points (17, 11) respectively at both the patient's knee pivot axis (38) and ankle joint axis (68) enables the reorientation mechanism (4, 80) to at least partially mimic the ankle and knee bending motion performed by a human standing from a seated position.

[0589] Thus, optimising the positions of the pivot axes (20, 21, 22) is a key design criterion for a patient moving device (3). Despite the above discussed efficacy of using a plurality of pivots, an inherent consequence is that the resultant path traversed by the patient support (5) is not a constant radius circular arc section, but instead is curvilinear, compounded by the effects of both rotations.

[0590] Thus, to effectively analyse, define and compare the attributes of different reorientation mechanism configurations, it is necessary to utilise some alternative representations for the rotational behaviour of a body such as the kinematic concept of an instant centre of rotation. Also known as the instant velocity centre, the instant centre of rotation is a point fixed to (or, relative to) a body undergoing planar movement that has zero velocity at a particular instant of time while the velocity vectors of the trajectories of other points in the body generate a circular field around this point.

[0591] Performing repeated or multiple instant centre of rotation calculations enables the generation of: [0592] an averaged centre-of-rotation; i.e., the average of multiple instant centre of rotation measurements, and [0593] a centroid; i.e., the path traced by the instantaneous centre of rotation.

[0594] FIG. 21A shows an exemplary schematic representation of the movement trajectories of a patient (25) during patient handling movement through a torso inclination angle θ of 70°, with an interior hip angle β of 135°, and an ankle/tibia joint rotation about the secondary pivot of Q around 15°. The respective paths traced by the patient's hips (66), CoM (69), and Jugular notch (62) depicted between the start, midpoint and end position are also shown, together with the averaged centre-of-rotation (CoR) positions (i.e., hip CoR (71), CoM CoR (72), Jugular notch CoR (73)) respectively, calculated from the start, midpoint and end position for each of the hips (66), CoM (69) and Jugular notch (62) respectively. FIG. 21B shows an enlarged view of the review of FIG. 21A adjacent the primary pivot axis (20)/knee joint axis (38). It will be appreciated that while convenient, the illustration of the midpoint CoR positions is not limiting and any point other point along the trajectory path may be calculated and displayed.

[0595] FIG. 22A shows a schematic representation corresponding to FIG. 21, of the movement trajectories of a patient (25) during patient handling movement through a torso inclination angle θ of 70°, with an interior hip angle β of 135°, and an ankle/tibia joint rotation at the secondary pivot of Ω around 15°. The respective paths traced by the patient's hips (66) CoM (69) and Jugular notch (62) depicted between the start, midpoint and end position are also shown, together with corresponding centroid positions (i.e., hip centroid (74), CoM centroid (75), Jugular notch centroid (76)), respectively calculated continuously from the start, via the midpoint and to an end position for each of the hips (66), CoM (69) and Jugular notch (62) respectively. To aid clarity, FIG. 22B shows an enlarged view of the view of FIG. 22A adjacent the primary pivot axis (20)/knee joint axis (38).

[0596] As shown in FIGS. 21 and 22, both the averaged centre-of-rotations (71, 72, 73) and centroid representations (74, 75, 76) are adjacently clustered in an ‘effective’ pivot’ region (77) located in front of the patient's knee joint axis (38) in the horizontal plane and substantially at or below the knee joint axis (38) and above the ankle/secondary pivot axis (21) in the vertical plane.

[0597] This configuration provides the previously described, desired effects of an ‘effective’, ‘virtual’ or ‘equivalent’ pivot position during patient handling which allows the patient (25) to be tilted forwards without excessive vertical movements, whilst minimising undesirable hamstring stretching. It will be also understood that as the patient's knee contact surface (40) (not shown in FIGS. 21-22) is in contact with the knee-rests (28), located co-axially with the primary pivot axis (20), the position of an averaged centre-of-rotation (71, 72, 73) and centroid representations (74, 75, 76) may be readily defined with respect to the primary pivot axis (20).

[0598] Thus, the averaged hip, CoM and/or Jugular notch centre-of-rotation (71, 72, 73) during patient handling is located within at least one of: [0599] a rectangular region dimensioned 250 mm×450 mm horizontally and vertically respectively, and positioned 50 mm horizontally towards the patient side (25) and 400 mm vertically downwards from the primary pivot axis (20); [0600] a rectangular region 175 mm×325 mm horizontally and vertically respectively, and positioned 50 mm horizontally towards the patient side (25) and 400 mm vertically downwards from the primary pivot axis (20); [0601] a rectangular region extending 150 mm horizontally towards the patient side (25) and 300 mm vertically from the primary pivot axis (20).

[0602] The hip, CoM and/or Jugular notch centroid (74, 75, 76) is located within at least one of: [0603] a rectangular region dimensioned 250 mm×450 mm horizontally and vertically respectively, and positioned 50 mm horizontally towards the patient side (25) and 400 mm vertically downwards from the primary pivot axis (20); [0604] a rectangular region 175 mm×325 mm horizontally and vertically respectively, and positioned 50 mm horizontally towards the patient side (25) and 400 mm vertically downwards from the primary pivot axis (20); [0605] a rectangular region extending 150 mm horizontally towards the patient side (25) and 300 mm vertically from the primary pivot axis (20).

[0606] Therefore, the present invention may, at least in part, be distinguished from the prior art by the identifying characteristic that an averaged centre-of-rotation (72) or centroid (75) of the path of the CoM during patient handling is located within said effective pivot region (77).

[0607] Changing an observer's frame-of-reference origin to be positioned at a specific part of the patient moving device (1) provides a powerful simplification tool to depict, compare and analyse the relative movements of the patient moving device (1) and its components.

[0608] As shown and discussed above, the rotational movement of the primary pivot (17) about the primary pivot axis (20) causes the reorientation mechanism (4) and, thus, the attached patient support (5)) to circumscribe a constant-radius circular arc. This circular arc movement of the reorientation mechanism/patient support (4, 5), is superimposed/compounded with the separate circular arc path circumscribed by rotational movement of the secondary pivot (11) (at, or adjacent the patient's ankles (68) about the secondary pivot axis (21). The resultant composite movement is a curvilinear path is inherently more difficult to compare directly with the movement produced by other patient moving devices. This composite movement does allow the patient's knees contact surfaces (40) (in contact with the knee-rests (37) at the primary pivot (17)) to move forwards concurrently with their torso (63) being rotated forwards in conjunction with the rotational movement of the patient support (5).

[0609] As identified previously, it is this very composite movement that provides key advantages over prior art alternatives with fixed position knee-rests (37), or those without knee rests (37) altogether.

[0610] Redefining the observer's frame of reference origin to be the primary pivot axis, allows the movement of both the secondary pivot and the reorientation mechanism/patient support about the primary pivot axis to be represented by simple, constant-radius, circular arcs.

[0611] FIGS. 23-25 provide an alternative interpretation, explanation and analysis means to visualise, conceptualise and/or represent the spatial, dynamic and geometric inter-relationships of the components of the patient moving device (1) during patient handling entirely with respect to said primary pivot axis (17), whereby any relative rotational movement of any part or point on the patient-moving device (1) is defined by a predetermined angular range Ø (where Ø is measured clockwise and where 0° is vertical).

[0612] In instances where the value is known, the linear separation between the primary pivot axis (20) and any other part, or point, of the patient moving device (1) may be represented in conjunction with the angular value Ø, by a radius value r. Such notation or nomenclature is also widely referred to as a polar co-ordinate system, i.e. with a reference point/origin referred to as the pole, where the angular value Ø is also referred to as the angular coordinate, polar angle, or azimuth and the radius value r as the radial coordinate, radial distance or just radius from the pole.

[0613] In FIG. 23, the movement of the patient movement device (1) is depicted between the patient loading and unloading positions. As representative metrics, the path travelled by the CoM (69) and the tertiary pivot (22), with respect to the primary pivot/primary pivot axis/knee rests (17, 20, 37) are shown with respective predetermined angular range Ø and radius r. Both the CoM (69) and tertiary axis (22) paths are also transposed onto a polar diagram shown in FIG. 24, together with several other relative rotations.

[0614] In additional to the CoM (69) and tertiary pivot (22), plots of the relative movement of any point or region of interest may be easily created using the polar co-ordinates showing the relative rotational movement of any other part or position of the patient moving device (1) during said patient handling, including the: [0615] secondary pivot (21) [0616] chassis (3); [0617] patient-support (5); [0618] reorientation mechanism (4), [0619] operating handle (6), [0620] patient securement strap (56) [0621] any part of same, and/or [0622] any other point on said patient-moving device, defined by a corresponding annulus sector or arc, each annulus sector or arc individually defined by a predetermined angular range and radius range Ø, r.

[0623] Solely for comparative value, FIG. 24 also shows the patient handling paths travelled by; [0624] the distal end of the operating handle (6), [0625] the securement point (58) of the patient securement strap (56) to the handle (6) with Ø=24-94.5° (for θ=70°) and r=560 mm, [0626] lowermost point of a patient-engaging outer surface (39) of the patient-support (5) with Ø=280-350° (for θ=70°) and r=310 mm,

[0627] together with the [0628] CoM (69) arc with Ø=208.5-278.5° (for θ=70°) and r=434 mm, and [0629] Tertiary pivot (22) arc with Ø=180°-198.5° (for θ=70° and Ω=15°) and r=41 mm

[0630] It will be noted that any part, or point, of the patient moving device (1) not undergoing any relative rotational movement respect to said primary pivot axis (17) will be represented by a fixed angular point, i.e., not an arc.

[0631] It should be further noted that any prior art patient moving devices with fixed position knee-rests (relative to the chassis/patient's ankles) will produce non-constant radius arcs for its CoM path relative to the knee joint axis and are thus easily distinguishable from the preferred embodiments described herein.

[0632] FIG. 25 shows, by way of comparison with the present embodiment, the prior art device shown in FIG. 10 with fixed position knee rests (37) (with respect to the chassis (2)). The relative movement of the prior art device of its CoM arc (91) is not at a fixed radius to the primary pivot axis (20) and the fixed angular value (90) (with Ø=195°) of its secondary pivot (11) contrasts starkly with the angular arc of Ø=180°-198.5° for the present embodiment.

[0633] It will be appreciated that patients may not be sitting on seating of uniform height or orientation and it may be necessary to lower or raise the patient support (5) so it engages with the proper portion of the patient's anterior torso. It may be possible to provide a vertical adjustment mechanism on the patient support attachment to the coupler link (15) to achieve such variability. However, the particular geometry of the coupled reorientation mechanism (4) of preferred embodiments enables the patient support (5) to be raised or lowered vertically without moving the patient support (5) relative to the coupler link (15). FIG. 26 shows a schematic representation of the vertical height adjustment capabilities of the patient moving device (1).

[0634] In FIG. 26, position ‘B’ of the patient support (5) shows the patient support with contact surface aligned vertically. If the patient is at a lower seating the reorientation mechanism may be rotated to lower the patient support vertically to position ‘A’. If the patient is at a higher seating the reorientation mechanism may be rotated to raise the patient support vertically to position ‘C’. Position ‘D’ represents the patient support (5) in the transport position.

[0635] As can be seen from FIG. 26, the reorientation mechanism (4) may be reorientated such that the patient support (5) is raised or lowered without significantly moving the primary pivot (17).

[0636] Preferred embodiments of the invention have been described by way of example only and modifications may be made thereto without departing from the scope of the invention.