Abstract
A patient support apparatus having a central dual control system of casters with an actuating pedal. Two opposite casters are connected by a control shaft with hexagonal cross section. Both control shafts are mutually coupled via a connecting member to a linkage rod. A servomotor with a rack is coupled to the linkage rod. The servomotor is configured to change a position of the rack of the servomotor and thus change a position of the central dual control system of casters upon manual change of position of the actuating pedal and/or upon electrical activation of the servomotor to change a position of the actuating pedal to another position of the central dual control system of casters.
Claims
1. A patient support apparatus having a central dual control system of casters comprising at least two pairs of casters with at least one actuating pedal, whereas always two opposite casters are each connected by a control shaft with hexagonal cross section, whereas both control shafts with hexagonal cross section are mutually coupled via a connecting member to a linkage rod of the central dual control system wherein a servomotor (8) with a rack is coupled to the linkage rod, whereas the servomotor is configured to change a position of the rack of the servomotor and thus change a position of the central dual control system of casters upon manual change of position of the actuating pedal and/or upon electrical activation of the servomotor to change a position of the actuating pedal to another positon of the central dual control system of casters.
2. A patient support apparatus having a central dual control system of casters according to claim 1, wherein the servomotor comprises a Printed Circuit Board with micro switches and an internal mechanical part further comprising a pinion, a cogwheel and the rack, which comprises a rack protrusion on its bottom side for attaching to the linkage rod, whereas the lateral side of the rack comprises at least one bottom hole (18) on the bottom side and at least one upper hole on the upper side.
3. The patient support apparatus having the central dual control system of casters according to claim 2, wherein the servomotor comprises the pinion, a holder, the cogwheel, the Printed Circuit Board with at least one micro switch, a toothed segment with at least one hole for at least one micro switch.
4. The patient support apparatus having the central dual control system of casters according to claim 1, wherein the servomotor can be attached to the control shaft with hexagonal cross section.
5. The patient support apparatus having the central dual control system (3) of casters according to claim 1, wherein the servomotor is removable from the linkage rod.
Description
LIST OF DRAWINGS
[0024] Various advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiments when read in light of the accompanying drawings:
[0025] FIG. 1 shows arrangement of casters on the bed undercarriage excluding the base frame, which is not shown, and detailed attachment of a servomotor for central control of casters,
[0026] FIG. 2 shows schematically detailed view of internal arrangement of a servomotor,
[0027] FIG. 3 shows exploded view of a servomotor.
[0028] FIG. 4 shows the undercarriage with a servomotor.
[0029] FIG. 5 shows detailed view of position of a servomotor.
[0030] FIG. 6 shows exploded view of a servomotor.
EXEMPLARY EMBODIMENTS OF THE INVENTION
[0031] Patient support apparatuses being e.g. hospital beds, nursery beds, stretchers, examinational chairs or other suitable apparatuses for use in healthcare facilities (hereinafter be referred to as a bed) comprise an undercarriage with casters to move the bed easily to desired place. FIG. 1 shows schematically an undercarriage 1 with casters 2 and detailed view of an entire central dual control system 3 of casters. Casters 2 may be conventional casters, however preferably these casters 2 comprise a triple cam that is disclosed in the international patent application WO 2022068978 filed by the same applicant, which is thereby included herein in its entirety. The undercarriage 1 of a bed may comprise another type of casters 2 comprising a two-way band brake that is disclosed in the international patent application WO 2021223782 filed by the same applicant, which is thereby included herein in its entirety, whereas also such casters may comprise the above referred triple cam.
[0032] The central dual control system 3 of casters comprises a control shaft 5 with hexagonal cross section that couples two opposite casters, either at the head end of foot end in relation to base frame of the bed. In preferred embodiment, a connecting member 6 is located in the middle of the control shaft 5, attached to the control shaft 5 on one end, and on another end it is attached to one end of a linkage rod Z. Another end of the linkage rod Z is coupled via second connecting member 6 to the other control shaft 5 which couples the second pair of the casters 2. In another embodiment, the connecting member 6 may be positioned anywhere on the control shaft 5. In the preferred embodiment, a motor 8 is located in the middle of the linkage rod Z in relation to the undercarriage 1. It should be noted that the motor 8 may be located anywhere on the linkage rod Z, or anywhere on at least one control shaft 5.
[0033] The central dual control system 3 of casters is actuated mechanically by an actuating pedal 4, or remotely by a remote controller (not shown) attached to the support deck, side rail or headboard or footboard, via cable or wirelessly. The remote controller may be coupled directly to the 8 or a control unit of the bed (not shown). The remote controller is not shown on the picture, however at present it is a conventional standard component of many types of beds. The FIG. 1 shows a part of the undercarriage 1 with casters 2 that are coupled by a control shaft 5, preferably with hexagonal cross section. At least one actuating pedal 4 is located on one end of the control shaft 5. Actuating pedals 4 may be radially disposed on opposite sides of the control shaft 5 or may be located in the middle of linkage rod Z. By actuating at least one actuating pedal 4, the control shaft 5 turns and changes position of another actuating pedal 4 on the opposite end of the control shaft 5. Actuating of at least one actuating pedal 4 causes transfer of movement on the linkage rod Z, which is coupled to the second control shaft 5 via connecting member 6, and thus causes operation of the second pair of the casters 2 on the opposite end of the undercarriage 1. This mechanical control of the central dual control system 3 of casters 1 may be operated using actuating pedals 4 on any side of the undercarriage 1.
[0034] In the preferred embodiment, a motor 8, preferably servomotor, is located in the middle of the linkage rod Z. It should be noted the motor 8 may be disposed anywhere on the linkage rod Z. The servomotor 8 is fixed to the linkage rod Z at the point of a protrusion 9 on the linkage rod Z. The servomotor 8 operates the linkage rod Z, which then operates the casters 2 by positioning the casters 2 into three positions, remotely by a remote controller. The servomotor 8 may be controlled by the remote controller via cable or wirelessly using wireless controllers. It should be noted that the servomotor 8 may be substituted by any electric motor, hydraulic motor or any other know motor suitable to operate healthcare facility beds. The central dual control system 3 of casters may be in parallel operated (or actuated) mechanically by actuating pedals 4 or electrically by motor 8, it means may be operated dually.
[0035] The FIG. 2 shows a motor 8 and its internal mechanical part 10 operated by the motor 8 and internal gearing which enables dual operation and actuation of the central dual control system 3 of the casters 2. The FIG. 2 shows detailed disposition of the servomotor 8 comprising a rack 13. Rack protrusions 14 are visible on the bottom side of the rack 13. The rack protrusions 14 form a grove which engages a protrusion 9 of the linkage rod Z central dual control system 3 of the casters 2. This structure forms mechanical linkage between the linkage rod Z and the servomotor 8. A pinion 12 of the servomotor 8 interlocks a cogwheel 11 that operates the rack 13 by which a higher transference number is reached. This internal mechanical part 10 of the servomotor 8 may operate and control dually the individual positions of the casters 2. It means that the linkage rod Z of the central dual control system 3 of the casters 2 is operated and controlled either by the servomotor 8 so that the casters 2 are positioned into position braked, unbraked or straight movement direction (ride), or manually using the actuating pedal 4 and the linkage rod Z of the central dual control system 3 of the casters 2 so that the casters 2 are positioned into position braked, unbraked or straight movement direction (ride). Both above stated manners may be operated simultaneously, in parallel, without any need to return any component to an initial neutral position. Both mechanisms of dual control may be operated from any position in which the central dual control system 3 of the casters 2 is positioned.
[0036] The FIG. 3 shows exploded view of a servomotor 8 comprising a cogwheel 11. which is in contact with a pinion 12 of the servomotor 8, which moves a rack 13 by using the cogwheel 11. The rack 13 comprises rack protrusions 14 on the bottom side of the rack 13. Rack protrusions 14 form an opening on their bottom side through which the servomotor 8 is fixed to a linkage rod Z of the central dual control system 3 of the casters 2. Fixing to the linkage rod Z is not shown. The lateral side of the rack 13 comprises two bottom holes 18 of a micro switch and two upper holes 19 of a micro switch which engage two micro switches: a bottom micro switch 16 and an upper micro switch 17. Two micro switches 16 and 17 signal or indicate a position of the internal mechanical part 10 of the servomotor 8 according to a combination of on/off status of the micro switches 16 and 17. Micro switches 16 and 17 are located on the Printed Circuit Board 15 on which the entire control logic of the servomotor 8 is positioned. It should be noted that the control logic of the servomotor 8 may be analogue, or digital, however the logic type is not a subject matter of this invention herein.
[0037] The FIG. 4 shows location of a servomotor 8 in relation to an undercarriage 2 whereas the servomotor 8 is fixed to a control shaft 5 with hexagonal cross section which operates casters 2 and couples two opposite positioned casters 2 together. The FIG. 4 clearly shows that the undercarriage comprises four casters 2, whereas two opposite casters 2 at the head end of the bed and two opposite casters 2 at the foot end of the bed are coupled with a linkage rod Z of the central dual control system 3 of the casters 2 via a connecting member 6 on the control shaft 5 with hexagonal cross section. The linkage rod Z of the of the central dual control system 3 of the casters 2 which couples the control shafts 5, transfers movement of one pair of the casters 2 to the other pair of the casters 2. One pair of the casters 2 is operated and controlled by an actuating pedal 4, preferably by more actuating pedals 4 and the other pair of the casters 2 is operated remotely by using servomotor 8, which is operated by remote controller (not shown). The remote controller may be positioned anywhere on a side rail, or a bed frame or a headboard or footboard of the bed and is connected with the servomotor 8 by cable. It should be noted that in another embodiment the remote controller may communicate with the 8 wirelessly via wifi, Bluetooth or any other wireless technology (not shown). The servomotor 8 is preferably a rotation servomotor where the outlet movement of the servomotor 8 is rotational and the internal mechanical part 10 of the servomotor 8 moves along the toothed segment 21 axis.
[0038] The FIG. 5 shows two views of a part of an undercarriage 1. The left view shows a caster 2 attached to a control shaft 5 with hexagonal cross section which comprises a connecting member 6 located in the middle in relation to the control shaft 5. The connecting member 6 is on its opposite end coupled to a linkage rod Z of the central dual control system 3 of the casters 2. A servomotor 8 is positioned next to the connecting member 6 on the control shaft 5. The FIG. 5 shows only a part of the servomotor 8 with a toothed segment 21. The right view shows also a servomotor 8 with a toothed segment 21. In this embodiment of the servomotor 8 an internal rotational toothed segment 21 is used instead of a rack 13. This toothed segment 21 is attached directly to the control shaft 5 with hexagonal cross section. The toothed segment 21 comprises holes 18 and 19 to operate micro switches 16 and 17.
[0039] The FIG. 6 shows an exploded view of a rotational servomotor 8. The servomotor 8 comprises an internal mechanical part 10 of the servomotor 8, a pinion 12, a holder 22, a cogwheel 11, a Printed Circuit Board 15 with micro switches 16 and 17, a toothed segment 21 with a hole to attach a control shaft 5 with hexagonal cross section, and holes 18 and 19, and micro switches 16 and 17. The entire servomotor 8 is located beneath an enclosure 20 of the servomotor 8. The toothed segment 21 comprises a hexagonal opening which engages the control shaft 5 with hexagonal cross section. The FIG. 6 further shows the holes 18 and 19 in the toothed segment 21 to sense positions by means of micro switches 16 and 17 to define the position of the control shaft 5 with hexagonal cross section which couples and operates the casters 2.
LIST OF REFERENCES
[0040] 1. Undercarriage [0041] 2. Caster [0042] 3. Central dual control system (of casters) [0043] 4. Actuating pedal (of central control mechanism) [0044] 5. Control shaft (with hexagonal cross section) [0045] 6. Connecting member [0046] 7. Linkage rod [0047] 8. Servomotor (motor) [0048] 9. Protrusion (to fix the servomotor) [0049] 10. Internal mechanical part of the servomotor [0050] 11. Cogwheel [0051] 12. Pinion [0052] 13. Rack [0053] 14. Rack protrusion (for attaching to linkage rod) [0054] 15. Printed Circuit Board (PCB) [0055] 16. Bottom micro switch [0056] 17. Upper micro switch [0057] 18. Bottom holes (of micro switch) [0058] 19. Upper holes (of micro switch) [0059] 20. Enclosure [0060] 21. Toothed segment [0061] 22. Holder
