Seat and crib arrangement

Abstract

The present invention relates to an infant seat and crib arrangement (10). The infant seat and crib arrangement (10) comprises a seat (14) configured to support an infant in a sitting position, a crib configured to enclose an infant and a frame (12). The frame (12) is configured for change between a first disposition in which the seat (14) engages removably with the frame to thereby bring the seat into use and a second disposition in which the crib removably engages with the frame to thereby bring the crib into use.

Claims

1. An infant seat and crib arrangement comprising: a seat configured to support an infant in a sitting position; a crib configured to enclose an infant, the crib and the seat separate from each other; and a frame configured to support the seat or crib in a position of use above a support surface and configured for change between a first disposition in which the seat engages removably with the frame to thereby bring the seat into use and a second disposition in which the crib removably engages with the frame after removal of the seat from the frame to thereby bring the crib into use, wherein the frame comprises first and second pairs of legs and first and second pairs of arms, the first pair of arms being adjacent the first pair of legs and the second pair of arms being adjacent the second pair of legs, a space for receiving the seat or the crib being defined between the first pair of legs and the second pair of legs and being adjacent to and bounded by part of the legs, wherein the seat or crib is received in part between the first and second pairs of legs in the position of use with distal ends of the first and second pair of legs adapted to contact the support surface, wherein the frame is configured for relative rotation of the arms in each of the first and second pairs of arms whereby distal ends of the arms in each pair are spaced apart further from each other in the second disposition than in the first disposition, and wherein, in the first and second dispositions, proximal ends of the legs in the first pair of legs are adjoining to form a first apex such that the legs in the first pair of legs slope away from the first apex, proximal ends of the legs in the second pair of legs are adjoining to form a second apex such that the legs in the second pair of legs slope away from the second apex, the arms in the first pair of arms extend away from the first apex, and the arms in the second pair of arms extend away from the second apex.

2. The infant seat and crib arrangement according to claim 1 wherein the arms in each of the first and second pairs of arms define an acute angle between each other when in the first disposition and extend substantially in a line when in the second disposition.

3. The infant seat and crib arrangement according to claim 1 wherein, in the first disposition, the arms in the first pair of arms slope away from the first apex in alignment with the first pair of legs and the arms in the second pair of arms slope away from the second apex in alignment with the second pair of legs, and wherein, in the second disposition, the arms in the first pair of arms extend in substantially opposite directions from the first apex and the arms in the second pair of arms extend in substantially opposite directions from the second apex.

4. The infant seat and crib arrangement according to claim 1 wherein the arms of the first and second pairs of arms opposing each other across the seat or crib receiving space are attached to each other by a respective elongate arm member.

5. The infant seat and crib arrangement according to claim 4 wherein the legs of the first and second pairs of legs opposing each other across the seat or crib receiving space are attached to each other by a respective elongate leg member, each elongate arm member and each elongate leg member being extensible.

6. The infant seat and crib arrangement according to claim 1 wherein the frame comprises first and second hinges, the first hinge being at the first apex and providing for relative rotation of the arms in the first pair of arms and the second hinge being at the second apex and providing for relative rotation of the arms in the second pair of arms.

7. The infant seat and crib arrangement according to claim 6 wherein the frame is configured such that the first hinge provides for relative rotation of the legs in the first pair of legs and the second hinge provides for relative rotation of the legs in the second pair of legs whereby the distal ends of the legs in each pair of legs are spaced apart further from each other when in the second disposition than when in the first disposition.

8. The infant seat and crib arrangement according to claim 6 wherein the frame comprises a locking device which is operative to releasably hold the frame in each of the first and second dispositions, the locking device comprising two recesses and a protrusion which is biased to be received in each of the two recesses, the two recesses being spaced apart on a part of one of the first and second hinges, the protrusion being mounted on one of the arms in a respective one of the first and second pairs of arms or on one of the legs in a respective one of the first and second pairs of legs, rotation about the first and second hinges between the first and second dispositions causing movement of the two recesses relative to the protrusion whereby the protrusion is received in one of the two recesses in the first disposition and is received in the other of the two recesses in the second disposition.

9. The infant seat and crib arrangement according to claim 1, wherein the frame comprises a hinge arrangement, the frame changeable between the first and second dispositions by way of the hinge arrangement.

10. The infant seat and crib arrangement according to claim 1 wherein each of the first and second pairs of arms comprises a first arm and a second arm, the two first arms are coupled to each other by a first elongate arm member and the two second arms are coupled to each other by a second elongate arm member whereby movement of one of the two first arms between the first and second dispositions causes corresponding movement of the other of the two first arms, and movement of one of the two second arms between the first and second dispositions causes corresponding movement of the other of the two second arms.

11. The infant seat and crib arrangement according to claim 10 wherein each of the first and second elongate arm members attaches at opposite ends of the elongate arm member towards distal ends of the respective ones of: the two first arms; and the two second arms.

12. The infant seat and crib arrangement according to claim 11 wherein each of the first and second elongate arm members is configured to change its length whereby a separation between the first and second pairs of arms is changed to thus change a width of the frame.

13. The infant seat and crib arrangement according to claim 1 further comprising a cot for an infant, the frame configured to support the cot such that the cot is adapted to be spaced apart from a floor on which the frame is supported.

14. The infant seat and crib arrangement according to claim 1 wherein the seat comprises a unitary seat body defining a base, opposing sides and a back, the base, opposing sides and the back defining an infant receiving space, the seat further comprising attachment members attached to the seat body which are configured to engage with the frame to thereby attach the seat body to the frame.

15. The infant seat and crib arrangement according to claim 1 wherein the crib comprises a crib body, the crib body comprising a pliable material defining a substantially rectangular base and substantially rectangular sides.

16. The infant seat and crib arrangement according to claim 1 wherein in the position of use, the first pair of arms are laterally adjacent the first pair of legs and the second pair of arms are laterally adjacent the second pair of legs, and the seat or crib is positioned with the first pair of legs and the second pair of legs laterally adjacent to opposing lateral sides of the seat or crib, and wherein lateral is in a direction generally parallel to the support surface.

17. An infant seat and crib arrangement, comprising: a seat configured to support an infant in a sitting position; a crib configured to enclose an infant, the crib and the seat separate from each other; and a frame configured for change between a first disposition in which the seat engages removably with the frame to thereby bring the seat into use and a second disposition in which the crib removably engages with the frame after removal of the seat from the frame to thereby bring the crib into use, wherein the frame comprises first and second pairs of legs and first and second pairs of arms, the first pair of arms being adjacent the first pair of legs and the second pair of arms being adjacent the second pair of legs, a space for receiving the seat or the crib being defined between the first pair of legs and the second pair of legs, wherein the frame is configured for relative rotation of the arms in each of the first and second pairs of arms whereby distal ends of the arms in each pair are spaced apart further from each other in the second disposition than in the first disposition, wherein, in the first and second dispositions, proximal ends of the legs in the first pair of legs are adjoining to form a first apex such that the legs in the first pair of legs slope away from the first apex, proximal ends of the legs in the second pair of legs are adjoining to form a second apex such that the legs in the second pair of legs slope away from the second apex, the arms in the first pair of arms extend away from the first apex, and the arms in the second pair of arms extend away from the second apex, and wherein the first and second pairs of arms are coupled for rotation relative to the rest of the frame between: a first arm disposition in which the arms of the first and second pairs of arms are adapted to extend obliquely towards a floor on which the frame is supported and when the frame is in the first disposition; and a second arm disposition in which the arms of the first and second pairs of arms are adapted to extend generally parallel to the floor when the frame is in the second disposition.

18. An infant seat and crib arrangement, comprising: a seat configured to support an infant in a sitting position; a crib configured to enclose an infant, the crib and the seat separate from each other; and a frame configured for change between a first disposition in which the seat engages removably with the frame to thereby bring the seat into use and a second disposition in which the crib removably engages with the frame after removal of the seat from the frame to thereby bring the crib into use, wherein the frame comprises first and second pairs of legs and first and second pairs of arms, the first pair of arms being adjacent the first pair of legs and the second pair of arms being adjacent the second pair of legs, a space for receiving the seat or the crib being defined between the first pair of legs and the second pair of legs, wherein the frame is configured for relative rotation of the arms in each of the first and second pairs of arms whereby distal ends of the arms in each pair are spaced apart further from each other in the second disposition than in the first disposition, wherein, in the first and second dispositions, proximal ends of the legs in the first pair of legs are adjoining to form a first apex such that the legs in the first pair of legs slope away from the first apex, proximal ends of the legs in the second pair of legs are adjoining to form a second apex such that the legs in the second pair of legs slope away from the second apex, the arms in the first pair of arms extend away from the first apex, and the arms in the second pair of arms extend away from the second apex, and wherein the first pair of legs lies in a first plane and the second pair of legs lies in a second plane, the first and second planes substantially parallel to each other, and each of the first and second planes extends adapted to extend generally orthogonal to a plane of a floor on which the frame is supported.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) Further features and advantages of the present invention will become apparent from the following specific description, which is given by way of example only and with reference to the accompanying drawings, in which:

(2) FIG. 1A is a perspective view of the infant seat and crib arrangement of the present invention when the seat is in place;

(3) FIG. 1B is a perspective view of the infant seat and crib arrangement of the present invention when the crib is in place;

(4) FIG. 1C is a perspective view of the infant seat and crib arrangement of the present invention when the cot is in place;

(5) FIG. 2A is a perspective view of the frame of the infant seat and crib arrangement of FIGS. 1A to 1C when in the collapsed disposition;

(6) FIG. 2B is a perspective view of the frame of FIG. 2A when in the first disposition;

(7) FIG. 2C is a perspective view of the frame of FIGS. 2A and 2B when in the second disposition;

(8) FIG. 3A is a side view of a hinge of the frame when the frame is in the collapsed disposition;

(9) FIG. 3B is a side view of the hinge of FIG. 3A when the frame is in the first disposition;

(10) FIG. 3C is a side view of the hinge of FIGS. 3A and 3B when the frame is in the second disposition;

(11) FIG. 4 is a perspective view of an arm member and lock arrangement; and

(12) FIGS. 5A to 5E illustrate operation of the lock arrangement of FIG. 4.

DESCRIPTION OF EMBODIMENTS

(13) The infant seat and crib arrangement of the present invention will now be described with reference to FIGS. 1A to 1C. The infant seat and crib arrangement of the present invention comprises a frame, a seat, a crib and a cot with the seat, the crib and the cot being brought into use with the frame at different times. A perspective view of the infant seat and crib arrangement 10 of the present invention is shown in FIG. 1A when the seat is in place. A perspective view of the infant seat and crib arrangement 10 of the present invention is shown in FIG. 1B when the crib is in place. A perspective view of the infant seat and crib arrangement 10 of the present invention is shown in FIG. 1C when the cot is in place. The infant seat and crib arrangement 10 comprises a frame 12 which is shown in each of FIGS. 1A to 1C.

(14) As may be seen from FIG. 1A a seat 14 is attached to the frame 12 when the frame is in a first disposition. The seat 14 comprises a unitary seat body 16 which defines a base, opposing sides and a back. The unitary seat body 16 is substantially rigid and is formed from PC ABS. The seat 14 also comprises a tray 18 which is removably attached to the seat body 16. The tray is substantially rigid and is formed from PC ABS. The seat 14 further comprises lugs, which are attached to the edge of the seat body 16, whereby the seat is attached removably to the frame 12. As may be appreciated from FIG. 1A, the infant seat and crib arrangement is operative as a highchair for an infant when configured as shown in FIG. 1A.

(15) As may be seen from FIG. 1B a crib 20 is attached to the frame 12 when the frame is in a second disposition. The crib 20 comprises a crib body 22. The crib body 22 comprises pliable material such as cloth configured to define a base and sides. The base of the crib is substantially rectangular whereby the sides comprise two pairs of opposing sides which define a volume of rectangular cross-section. The crib 20 further comprises lugs 24, which are attached to the crib body, whereby the crib is attached removably to the frame 12. As may be appreciated from FIG. 1B, the infant seat and crib arrangement is operative as a crib for an infant when configured as shown in FIG. 1B.

(16) As may be seen from FIG. 1C a cot 26 for an infant is attached to the frame 12 when the frame is in the first disposition. The cot 26 for an infant has the form of a Moses basket. The cot 26 comprises a cot body 28. The cot body 28 is formed from cloth. The cot body 28 further comprises rigid members which are disposed therein so as to determine and maintain the shape of the cot body. The cot 26 further comprises two lugs 30 which are integrally formed from cloth with the cot body 28. The lugs 30 are comprised in the cot midway along opposite sides of the cot body and such that each lug extends from a respective upper edge of the cot body. Each lug 30 defines a recess of generally semicircular form which is oriented down a respective side of the cot body. As shown in FIG. 1C, each lug receives a respective apex defined by the frame 12 when in the first disposition whereby the cot is suspended from the frame. Furthermore, when the lugs are fitted properly to the frame, the base of the cot 26 rests on the two spaced apart arm members described below with reference to FIGS. 2A to 2C.

(17) The frame 12 of FIGS. 1A to 1C will now be described in more detail with reference to FIGS. 2A to 2C. FIG. 2A provides a perspective view of the frame 12 of the infant seat and crib arrangement of FIGS. 1A to 1C when in the collapsed disposition. FIG. 2B provides a perspective view of the frame 12 of FIG. 2A when in the first disposition. FIG. 2C provides a perspective view of the frame 12 of FIGS. 2A and 2B when in the second disposition. The frame 12 comprises a first pair of legs 52 and a second pairs of legs 54 with the legs in each pair being spaced apart from each other. The legs are formed from wood. The first legs 56 of the first and second pairs of legs lie in a first plane and define a first side of the frame. The second legs 58 of the first and second pairs of legs lie in a second plane and define a second side of the frame. The first and second planes are substantially parallel and extend substantially orthogonal to a floor on which the frame is supported. A width of the frame 12 is therefore determined by a distance between the first legs 56 and the second legs 58.

(18) The first legs 56 of the first and second pairs of legs are mechanically coupled to each other towards their first proximal ends for relative rotation by way of a hinge 60. Second distal ends of the first legs 56 of the first and second pairs of legs each define a floor supporting surface on an end thereof. The second legs 58 of the first and second pairs of legs are mechanically coupled to each other towards their first proximal ends for relative rotation by way of a hinge 60. Second distal ends of the second legs 58 of the first and second pairs of legs each define a floor supporting surface on an end thereof. The hinges 60 are of the same form and function and are described further below and with reference to FIGS. 3A to 3C.

(19) The first and second legs 56, 58 in each of the first and second pairs of legs 52, 54 are rigidly coupled to each other by an elongate leg member 62 whereby the first and second legs move together. Each elongate leg member 62 is formed from aluminium. Each elongate leg member 62 extends between the first and second legs and attaches to the first and second legs at opposite ends of the leg member.

(20) Furthermore each leg member 62 is attached towards distal ends of the first and second legs. Each leg member 62 is configured for a change in its length whereby a separation between the first legs 56 of each pair and the second legs 58 of each pair is changeable. A width of the frame is thus changeable. Each leg member 62 comprises two cylindrical parts which engage telescopically with each other to thereby provide for length adjustment.

(21) The frame 12 further comprises a first pair of arms 64 and a second pair of arms 66. The arms are formed from wood. Each of the first and second pairs of arms comprises a first arm 68 and a second arm 70. The first arms 68 of the first and second pairs of arms are coupled towards their first proximal ends for relative rotation by way of the hinge 60 that provides for relative rotation of the first legs 56. The second arms 70 of the first and second pairs of arms are coupled for relative rotation towards their first proximal ends by way of the hinge 60 that provides for relative rotation of the second legs 58. The first and second arms 68, 70 in each of the first and second pairs of arms are rigidly coupled to each other by way of an elongate arm member 72 whereby the first and second arms move together. Each arm member 72 is formed from aluminium. Each arm member 72 extends between the first and second arms and attaches to the first and second arms at opposite ends of the arm member. Each arm member 72 is attached towards distal ends of the first and second arms. Each arm member is configured to change its length whereby a separation between the first arms in each pair and the second arms in each pair changeable. A width of the frame 12 is thus changeable when the length of the leg members 62 changes at the same time. Resistance against change in length of each arm member 72 is by way of a lock arrangement 74. The lock arrangement 74 is described below with reference to FIG. 4.

(22) Change in disposition of the legs and arms of the frame 12 will now be described with reference to FIGS. 2A to 2C. The frame 12 is shown in FIG. 2A in the collapsed disposition. When the frame 12 is in the collapsed disposition the first and second pairs of arms 64, 66 are pushed together whereby the first and second pairs of legs 52, 54 are also pushed together by way of lugs attached to the first and second pairs of arms which bear against the first and second pairs of legs. The first and second pairs of arms 64, 66 and the first and second pairs of legs 52, 54 rotate about the hinges 60. When in the collapsed disposition the first pair of arms and first pair of legs are nearby the second pair of arms and the second pair of legs such that first pair of arms and first pair of legs are substantially parallel with the second pair of arms and second pair of legs. As may be seen from FIG. 2A, the frame 12 is configured such that each arm in the first pair of arms 64 is side by side with a respective leg in the first pair of legs 52 whereby the arm is substantially coterminous with the leg in respect of their respective sides and having regard to the arm being shorter than the leg. Furthermore each arm in the first pair of arms 64 is inside its respective leg whereby an outside width of the frame is defined by the legs. Each arm in the second pair of arms 66 is likewise configured such that each arm in the second pair of arms is side by side with a respective leg in the second pair of legs 54 whereby the arm is substantially coterminous with the leg in respect of their respective sides and having regard to the difference in their lengths. Furthermore each arm in the second pair of arms 66 is inside its respective leg.

(23) When it is desired to bring the infant seat and crib arrangement into use, the frame 12 is changed from the collapsed disposition shown in FIG. 2A to either the first disposition shown in FIG. 2B or the second disposition shown in FIG. 2C. The frame 12 is changed from the collapsed disposition by pulling the first and second pairs of arms 64, 66 apart. As described in more detail below with reference to FIGS. 3A to 3C, the hinges 60 are configured such that movement apart of the first and second pairs of arms 64, 66 pulls the first and second pairs of legs 52, 54 apart until the arms and legs have the first disposition shown in FIG. 2B. Each side of the frame 12 therefore defines an A-frame with the apex of the A-frame being furthest from the floor during use of the frame. The first and second pairs of legs 52, 54 are 600 mm apart from each other and the first legs 56 are 533 mm apart from the second legs 58 when the frame is in the first disposition. Then either the seat of FIG. 1A or the cot of FIG. 1C is fitted to the frame 12. When the seat is fitted the top of the back of the seat is 828 mm above a floor on which the frame is supported. When use of the seat or the cot is complete, the seat or cot is removed from the frame 12. The first and second pairs of arms 64, 66 are then pulled further apart. As described in more detail below with reference to FIGS. 3A to 3C, the hinges 60 are configured such that such further movement apart of the first and second pairs of arms 64, 66 pulls the first and second pairs of legs 52, 54 further apart until the legs have the disposition shown in FIG. 2C. Upon yet further movement apart of the first and second pairs of arms 64, 66, the hinges 60 are configured such that the yet further movement apart of the first and second pairs of arms is no longer coupled to the legs whereby the legs remain in the disposition shown in FIG. 2C. The yet further movement apart of the first and second pairs of arms 64, 66 raises the first and second pairs of arms until they extend horizontally from the hinges 60 as shown in FIG. 2C. When the arms are raised such that they extend horizontally, the hinges 60 are configured as described below with reference to FIG. 3A to 3C to maintain the arms in the horizontal position. In addition, the lock arrangement 74 is operated to allow for extension of the arm members 72 and the opposite sides of the frame 12 are pulled apart to increase the width of the frame to the width shown in FIG. 2C. The lock arrangement 74 is then operative to restrict change in length of the arm members whereby the width of the frame is maintained as shown in FIG. 2C. The frame is 715 mm high, the first and second pairs of legs 52, 54 are 983 mm apart from each other and the first legs 56 are 780 mm apart from the second legs 58 when the frame is in the second disposition shown in FIG. 2C. The crib of FIG. 1B is then fitted to the frame 12.

(24) Side views of one of the hinges 60, 80 are shown in FIGS. 3A to 3C. Each hinge 60, 80 is formed from glass filled nylon. FIG. 3A is a side view of the hinge 60, 80 when the frame is in the collapsed disposition. A finger 82 is attached to one of the legs 84 such that it extends towards the other leg 86 and towards a cam arrangement 88 comprised in the hinge. The finger 82 comprises a protrusion 92 which extends laterally from an end of the finger towards the cam arrangement 88. The finger 82 is mounted for rotation on the leg about an axis which is parallel with the axis of rotation of the hinge 80. Furthermore, the finger is biased by a spring 94 towards the cam 88 whereby the protrusion 92 is urged against the periphery of the cam arrangement. The cam arrangement 88 is configured as follows. Each arm and each leg comprises a circular cam portion at its proximal end with the four cam portions being coaxially disposed to thereby form the cam arrangement 88. The leg other than the leg on which the finger 82 is mounted defines a first leg recess 96, a second leg recess 98 and a third leg recess 100. The first to third leg recesses are spaced apart from each other along a circumferential path defined by the leg's cam portion. Each leg recess is shaped to receive the finger protrusion 92. The finger protrusion 92 is received: in the first leg recess 96 when the frame is in the collapsed disposition shown in FIG. 3A; in the second leg recess 98 when the frame is in the first disposition shown in FIG. 3B; and in the third leg recess 100 when the frame is in the second disposition shown in FIG. 3C. The two legs are thus locked to each other when each of the collapsed, first and second dispositions. The arm adjacent the leg mounting the finger 82 defines a first arm recess 102 which is shaped to receive the finger protrusion 92. The first arm recess 102 lies on a circumferential path defined by the arm's cam portion at a location such that the finger protrusion 92 is received in the first arm recess when the frame is in the second disposition shown in FIG. 3C. The other arm defines a second arm recess 104 which is shaped to receive the finger protrusion 92. The second arm recess 104 lies on a circumferential path defined by the arm's cam portion at a location such that the finger protrusion 92 is received in the second arm recess when the frame is in the second disposition shown in FIG. 3C. Each of the two arms is thus locked to the leg mounting the finger 82 when the frame is in the second disposition. The other arm, i.e. the arm other than the arm adjacent the leg mounting the finger 82, defines a third arm recess 106 which is shaped to receive the finger protrusion 92. The third arm recess 106 lies on a circumferential path defined by the arm's cam portion at a location such that the finger protrusion 92 is received in the third arm recess when the frame is in the collapsed disposition shown in FIG. 3A. The other arm is thus locked to the leg mounting the finger 82 when the frame is in the collapsed disposition.

(25) Release of the finger protrusion 92 from arm or leg recesses to allow for change of the frame between dispositions is by manual movement of the finger 82 against the bias of the spring 94. Alternatively, the finger protrusion 92 is released by manual movement of the arms and without manual movement of the legs. The arm adjacent the leg mounting the finger 82 defines a first arm profile 108 on the circumferential path of the arm and which receives the finger protrusion 92 when the frame is in the collapsed disposition. The first arm profile 108 is shaped to push the finger progressively away against the spring bias as the arm is raised whereby the finger protrusion 92 is released from the first leg recess 96. The other arm defines second arm profile 132 on the circumferential path of the arm and which receives the finger protrusion 92 when the frame is in the first disposition. The first arm profile 132 is shaped to push the finger progressively away against the spring bias as the arm is raised whereby the finger protrusion 92 is released from the second leg recess 98.

(26) Manual movement of the arms 90 without the legs as described above causes movement of the legs 84, 86 by the following two mechanisms. According to the first mechanism, the leg 86 other than the leg mounting the finger 82 defines a channel (not shown) which describes an arc. The arm 90 adjacent the leg 86 defines a protrusion (not shown) which extends in the same direction as the axis of rotation of the hinge and which is received in the channel with the channel and protrusion being shaped and disposed such that the protrusion travels along the channel as the arm 90 is moved in relation to the leg 86. More specifically the channel and protrusion are shaped and disposed to allow for the arm 90 to be lifted from the position shown in FIG. 3A until the arm reaches an angle of 75 degrees. At this point, the protrusion reaches the end of the channel and the leg 86 is rotated with the arm 90. According to the second mechanism, the leg 84 mounting the finger 82 comprises a spigot 134 which is coaxial with the axis of rotation of the hinge. The adjacent arm 90 defines a spigot aperture which receives the spigot 134. The surface which defines the spigot aperture has two opposing spigot aperture protrusions 136 extending therefrom. The surface of the spigot 134 facing the surface defining the spigot aperture has two oppositely directed spigot protrusions extending therefrom at locations such that each spigot protrusion is received between the spigot aperture protrusions 136. The circumferential length of the spigot protrusions and the spigot aperture protrusions 136 is such that spigot protrusions travel along the space between the spigot aperture protrusions as the arm is lifted from the position shown in FIG. 3A until the arm reaches an angle of 75 degrees. At this point, an end of each of the spigot protrusions abuts against a respective spigot aperture protrusion whereby further lifting of the arm causes the leg to move with the arm. The two mechanisms thus mechanically couple lifting of one arm to its respective leg and mechanically couple lifting of the other arm to its respective leg.

(27) As described above, there is a hinge 60 at each of the two sides of the frame 12. Each of the two hinges 60 is comprised in the frame such that it is mirrored relative to the other hinge whereby there is reversal in respect of which arms and legs on each side of the hinges the coupling mechanisms are operative.

(28) A perspective view of an arm member 72 and the lock arrangement 74 is shown in FIG. 4. As can be seen from FIG. 4, the lock arrangement 74 is mounted on the outside of the first part of the arm member 72 which telescopically receives the second part of the arm member. The lock arrangement 74 comprises a housing 110 attached to the first part of the arm member 72 and a user operable slider 112 mounted on the housing for movement in a direction along the length of the arm member. The slider 112 is operated by a user to control the lock arrangement 74. Operation of the lock arrangement 74 of FIG. 4 will now be described with reference to FIGS. 5A to 5E which provide different views in longitudinal section through the lock arrangement and arm member 72 of FIG. 4.

(29) FIG. 5A shows the lock arrangement 74 when the first part 114 of the arm member and the second part 116 of the arm member are locked against their relative longitudinal movement when in the second disposition. The lock arrangement 74 further comprises a spring 117 and a ball bearing 118 within the housing 110. The spring 117 biases the slider 112 in the direction of the first part 114 to thereby maintain the lock arrangement in a locked condition. The ball bearing 118 is supported in a first aperture in the first part 114 for movement towards and away from the second part 116. The second part 116 defines a second aperture which is configured to receive the ball bearing 118 in part. As shown in FIG. 5A when the first and second parts 114, 116 are disposed relative to each other such that the first and second apertures are in registration, a surface of the slider 112 oriented towards the second part 116 bears against the ball bearing 118 whereby the ball bearing is forced through the first aperture towards the second part such that part of the ball bearing is received in the second aperture. The ball bearing 118 is thus received in both first and second apertures whereby the first and second parts 114, 116 are locked against relative longitudinal movement.

(30) When it is desired to unlock the first and second parts 114, 116, for example when changing from the second disposition to the first disposition, the user moves the slider 112 against the bias of the spring 117 towards the second part 116 as shown in FIG. 5B. The surface of the slider 112 which is oriented towards the second part 116 now longer bears against the ball bearing 118 whereby the ball bearing is free to move away from the second part such that it is no longer in the second aperture. The first and second parts 114, 116 are therefore no longer locked together by the ball bearing whereby the first and second parts are movable in relation to each other. The lock arrangement 74 further comprises a latch 120 which is mounted for rotation inside the housing 110 at an end of the housing along the arm member opposite the end of the housing which holds the slider 112 when the lock arrangement is in the condition shown in FIG. 5A. A distal end of the latch defines a first projection 122 with the latch being rotatable such that the distal end of the latch is raised or lowered. A distal end of the slider 112 which is oriented towards the latch 120 defines a second projection 124. The first and second projections 122, 124 are shaped such that as the slider 112 is moved to the location shown in FIG. 5B the second projection 124 bears against the first projection 122 and with progressive further movement of the slider raises the distal end of the latch 120.

(31) When the slider 112 has been moved against the bias of the spring 117 to its furthest extent the distal end of the slider has been moved relative to the distal end of the latch 120 such that the first protrusion 122 has moved beyond the second protrusion 124. When the first protrusion 122 has moved beyond the second protrusion 124 the latch 120 rotates such that first protrusion 122 drops down behind the second protrusion 124 as shown in FIG. 5C. Although not shown in FIG. 5C, a torsion spring is operative to urge the distal end of the latch downwards. When the lock arrangement 74 is in the condition shown in FIG. 5C and when the user has released the slider, engagement of the first and second protrusions 122, 124 presents resistance to movement of the slider 112 caused by the bias of the spring 117. Engagement of the first and second protrusions 122, 124 therefore keeps the lock arrangement 74 unlocked in the absence of user operation of the slider. The first and second parts 114, 116 are then moved relative to each other such that the second part is progressively further received within the first part, such as happens when changing from the second disposition to the first disposition, until a surface of a proximal part of the latch which is oriented towards the second part bears against a latch release 126 which is mounted on the second part such that it protrudes from the second part. The latch release 126 is shown in FIG. 4. The latch release 126 and the surface of the proximal part of the latch 120 which is oriented towards the second part 116 are shaped such that their relative movement raises the distal end of the latch whereby the first and second protrusions 122, 124 disengage from each other as shown in FIG. 5D. The slider 112 then moves under the bias of the spring (not shown in FIGS. 5D and 5E for clarity) back towards the ball bearing 118. The surface of the slider 112 which is oriented towards the second part 116 now bears again against the ball bearing 118 as shown in FIG. 5E. However because the first and second apertures are no longer in registration the ball bearing 118 is not operative to lock the first and second parts 114, 116 together. Upon withdrawal of the second part 116 from the first part 114 when changing back to the second disposition such that the arm member is lengthened to the extent that the first and second apertures are in registration, the ball bearing 118 is forced again into the second aperture by the slider 112 to thereby put the arm member back in the locked condition shown in FIG. 5A.