WO2006066321A1

WO2006066321A1 - Lifting device

Info

Publication number: WO2006066321A1
Application number: PCT/AU2005/001922
Authority: WO
Inventors: Richard Russell
Original assignee: Reapan Pty Limited
Priority date: 2004-12-24
Filing date: 2005-12-21
Publication date: 2006-06-29

Abstract

A lifting device (10) for lifting a chair (C1) having an occupant. The device (10) includes a base (12), a support (14) mounted to the base (12) and positionable beneath a portion of the chair (C1). The support (14) includes engagement means (62,64) operable to releasably engage a portion of the chair (C1) and secure the support (14) to the chair (C1). The device (10) also includes means (60) for raising the height of the support (14), relative to the base (12) for lifting the chair (C1) and the occupant off an underlying surface.

Description

Lifting Device

Technical Field

The present invention relates to a lifting device for lifting a chair having an occupant, in particular an elderly or infirm occupant having restricted mobility.

Background

A significant cause of injury and stress experienced by healthcare workers and carers results from the frequent need to lift elderly or infirm persons having restricted mobility, particularly from seated positions. Further, potential for injury and stress arises due to the need to safely lower such persons from an upright position to a seated position. Accordingly, many devices, for example sling or harness type devices, have been developed for lifting such persons from a seated position. Such devices may be suitable for lifting purposes once the person to be lifted has been located within the lifting sling or harness. However, such devices have been found to be unsatisfactory as significant time is often required in order to locate the person to be lifted within the sling or harness. Further, these devices require significant lifting of the person to be moved in order to initially manoeuvre the person into the sling or harness. Still further, such devices are generally suitable only for moving a person from one seated position to another. They do not allow lifting of a seated person into an upright position so that they may then walk as the lifting sling or harness remains about the person. Accordingly, such devices are inappropriate for reducing injury and stress due to lifting of elderly or infirm persons.

Alternative lifting devices exist which do not require a person to be manoeuvred into a sling or harness. In one form, such devices require the person to engage a portion of the device, typically by holding one or more handles or grips, while the handles or grips are raised to lift the person. Such devices require the person to be lifted to bear a significant proportion of their own weight in order to retain engagement with the handles or grips. Accordingly, such devices are inappropriate for lifting elderly or infirm persons who lack the capacity to bear such weight, even where such persons, once lifted are capable of walking unassisted.

Another significant cause of injury and stress experienced by healthcare workers and carers is the frequent need to transport elderly or infirm persons having restricted mobility. Many devices, typically referred to as wheelchairs, exist for transporting such persons. While such devices may be suitable for purposes of transportation between locations, they may, for a number of reasons, be unsatisfactory for use by an occupant wishing to be seated at a particular location. For example, due to the dimensions of such devices, they may not readily allow an occupant to be seated at a table. In an environment where a number of persons of restricted mobility are present, it may be uneconomical to provide such devices for each person. For these and other reasons it is common for such persons to be seated on a standard chair in a number of situations. However when it is subsequently necessary to transport such persons to another location, they must then be moved from the standard chair to a wheelchair or other such device for transportation. Further, the person may then be again moved from the wheelchair to a second standard chair at a further location. The operation of moving a person of restricted mobility from a standard chair to a wheelchair or from a wheelchair to a standard chair is generally performed by those responsible for the care of the person and can be quite difficult, particularly where the person to be moved is of a large mass. The performance of such an operation therefore exposes the carer to significant risk of injury.

It would therefore be desirable to simplify the lifting of a person, particularly a person of limited mobility. It would further be desirable to be able to lift a person, particularly a person of limited mobility, in a manner which reduces the risk of injury to those who are to perform the lifting operation. It would further be desirable to be able to lift a person who is capable of walking unassisted but incapable of lifting themselves from a seated position, to a height from which they can walk. It would further be desirable to be able to safely lower a person who is capable of walking unassisted but incapable of lowering themselves from an upright position to a seated position. It would further be desirable to be able to lift a person, particularly a person of limited mobility, in a manner which reduces the need for the person to be lifted to participate in the lifting operation. It would still further be desirable to simplify the transport of a person, particularly a person of limited mobility, from one location to another. It would still further be desirable to be able to move a person, particularly a person of limited mobility, in a manner which reduces the risk of injury to those who are to perform the moving operation. The present invention aims to meet at least some of these needs.

Summary of the Invention

According to one aspect, the present invention provides a lifting device for lifting a chair having an occupant, the device including; a base, a support mounted to the base and positionable beneath a portion of the chair, the support having engagement means operable to releasably engage a portion of the chair and secure the support to the chair; and means for raising the height of the support relative to the base for lifting the chair and the occupant off an underlying surface.

Reference to an underlying surface is to be understood to include any floor or ground surface.

Most preferably, the means for raising the height of the support also provides a means for lowering the height of the support relative to the base from a raised position. Such a device may be used to both lift a person from a seated position to an upright position and lower a person from an upright position to a seated position. In one embodiment, the means for raising the height of the support includes an inflatable device positioned beneath the support, wherein the inflation / deflation of the device causes, respectively, raising / lowering of the height of the support. Alternatively, the means for raising the height of the support may include a lifting cylinder or piston, which is extended to raise the height of the support relative to the base. The piston may then be retracted to lower the height of the support relative to the base. The piston may be actuated by any suitable means, including hydraulically. In a further alternative arrangement, the means for raising the height of the support may include a first and second lifting cylinder or piston. In such an arrangement, the lifting device further includes a support arm, the first piston being arranged between the base and the support arm and the second piston being arranged between the support arm and the support. In such an embodiment, the first piston is operable to raise the height of the support arm, and indirectly, the support, relative to the base, while the second piston is operable to raise the height of the support relative to the support arm.

The support may further be rotatable relative to the base, preferably, through 180°, more preferably, through 360°.

The support may be raised relative to the base to a plurality of heights. In one embodiment, the support may be raised relative to the base to a first height for transporting of a chair secured to the support. Further, the support may be raised relative to the base to a second height to aid the occupant of the chair in vacating the chair. Alternatively, the support may be raised to a first height for transporting a chair, and a plurality of further heights for aiding an occupant to vacate the chair, depending upon the height of the occupant. In particular, the support may be raised to a second or plurality of further heights so as to allow the occupant to easily walk unassisted once lifted. Further, the support may be lowered from a second or plurality of further heights so as to allow the occupant to easily be seated from an upright position. In embodiments having both a first and second lifting cylinder or piston, one of the first and second pistons may be operable to raise the support to a first height for transporting of the chair, while the other of the first and second pistons is operable to raise the support to a second height to aid the occupant of the chair in vacating the chair.

The support may adopt any suitable form. In one particularly preferred form, the support includes a platform for engaging the underside of the chair to be lifted. It is to be appreciated that the platform may have any suitable form and shape for use with a variety of potential chair designs. Alternatively, the support may include a support frame for engaging the underside of the chair. In one embodiment the support frame includes two support beams extending substantially in parallel to each other. The support frame may further include adjustment means for adjusting the spacing between the support beams. The adjustment means is operable to adjust the spacing between the support beams to enable positioning of the support beneath a portion of the chair. For example, where the device is to be used to lift a four- legged chair, the spacing of the support beams may be adjusted such that the support has a width enabling it to be easily positioned beneath the seat of the chair, between the left hand and right hand pair of legs. The spacing of the support beams may then be adjusted such that the beams are in close proximity to the insides of the respective left and right hand legs for securing of the support to the chair by the engagement means.

The adjustment means may take any suitable form such as a hydraulic cylinder or the like. Alternatively, the adjustment means may include a rack and pinion mechanism. In one embodiment, each of the support beams include at least one toothed rack, the support further including at least one correspondingly toothed pinion for engagement with and driving of the toothed racks.

Each of the support beams may include a first beam member and a second beam member, the first and second beam members having substantially parallel axes. The second beam member is moveable relative to the first beam member along its axis, such that the length of the support beams may be varied. The second beam member is moveable relative to the first beam member by any suitable means. In one embodiment, the first and second beam members respectively form the cylinder and piston of a hydraulic ram.

The support may further include a cover member covering the support frame. The cover member may include a first, fixed portion covering a first portion of the support frame and a second, extensible portion covering a second portion of the support frame, the second portion of the support frame including the support beams. The support may further include leg supports for supporting the legs of the occupant of the chair during lifting thereof. The leg supports may prevent the legs of the occupant from interfering with, or being injured by, the raising or lowering of the support. The leg supports may be pivotably mounted to the support so as to be pivotable from an active or extended position when the device is being used to lift a chair to an inactive or retracted position when the device is not being so used.

The support may further include retaining means for retaining an occupant of a chair in that chair while the chair is being lifted. The retaining means may take any suitable form, and in one embodiment, is in the form of a belt extending from the support.

The engagement means may take any suitable form. In one preferred form, the engagement means include one or more clamps provided at a periphery of the support, and operable to be clamped to the legs of a chair when the support is positioned beneath a portion thereof. The position of the clamps on the support may be adjustable so at to be configured for engagement with a variety of different chairs.

In another embodiment, the support is provided with a pair of clamps, the clamps disposed on opposite sides of the support. Each of the pair of clamps may include at least one moveable jaw, the moveable jaws operable to be moved along respective sides of the support to bring the clamps into engagement with a portion of a chair.

Each pair of clamps may include a first jaw provided on a respective first beam member of the support beam while a second jaw may be provided on the second beam member. Movement of the second member relative to the first allows movement of the first jaw relative to the second. In one form, the first and second jaws are inward facing jaws. For engagement of the chair, each pair of first and second jaws is positioned to have a portion of the chair there between, the second jaw being moved closer to the first by movement of the second beam member being relative to the first to bring each jaw into engagement with the portion of the chair. Alternatively, the first and second jaws may be outward facing jaws, the jaws initially positioned between portions of the chair and moved away from each other to engage those portions. In particular, the jaws may be configured for engagement of the chair legs.

In another embodiment, each of the clamps includes a pair of clamping arms. One of the pair of clamping arms may be fixed relative to the support, while the other of the pair is operable to pivot relative to the support. Alternatively, both clamping arms of each pair may move pivotably relative to the support. The or both pivoting clamping arms may be pivoted in one direction so as to move toward the other arm of the pair, for engagement of a portion of the chair. The or both arms may be further be pivoted in an opposite direction, for release of the engaged portion of the chair. The pivoting of the or both clamping arms may be driven by any suitable means.

In another embodiment, the support is provided with at least one strap for releasably engaging a portion of the chair. Preferably, the support includes a plurality of straps such that the support may be engaged with the chair at more than one location. In such an embodiment at least one strap engages a portion of the chair only, while another strap also passes over the lap of the occupant of the chair to form part of the retaining means for retaining the occupant while the chair is being lifted.

The device may further include means for tilting of the support relative to the base. Any suitable means for tilting the support relative to the base may be employed. The support may be tilted to allow for more secure engagement of the support to a chair. Further, the support may be tilted after engagement thereof with a chair to aid the occupant of the chair in vacating the chair. Further, the support may be titled when in a raised position so as to allow a person in an upright position to more easily be located within the lifted chair for lowering to a seated position. In one embodiment, the base is moveable over the underlying surface, enabling the chair and the occupant to be repositioned on the underlying surface. The base may be provided with one or more wheels for movement over the underlying surface. Alternatively, the base may be provided with rollers, casters or the like for movement over the underlying surface. Hereinafter, reference to wheels is to be taken to include other means for movement of the base as described above.

The person operating the device may manually move the base over the underlying surface. Alternatively, one or more of the wheels may be driven wheels. The driven wheels may be driven in a forward and a reverse direction for movement of the base over the underlying surface. Any suitable means for driving the wheels may be employed, as will be appreciated by those skilled in the art.

For increased manoeuvrability of the device over the underlying surface, one or more of the wheels may be pivotable about a vertical axis. The pivoting of the wheels may occur in response to movement of the device by the person operating it. Alternatively, the pivoting of the wheels may be driven. Again, any suitable means for driving the pivoting of the wheels may be employed.

In one embodiment, the base includes a first base portion and a second base portion, the first base portion being pivotably connected to the second base portion. Each of the first and second base portions may be provided with a respective pair of wheels.

The second base portion may further be provided with a pair of auxiliary wheels. The auxiliary wheels may be spaced laterally outward of the primary wheels to provide increased lateral stability to the second base portion.

The wheels of either or both of the first and second base portions may be driven wheels as described above. Preferably, the wheels of either the first or second base portion are driven wheels while the support is mounted to the other of the first and second base portion. The pivoting of one base portion relative to the other may be in response to movement of the device by the person operating it. Alternatively, the pivoting may be driven. In an embodiment where the pivoting is driven, the device may further include an actuator for driving the pivoting. The actuator may be any means suitable for driving the pivoting such as a hydraulic cylinder or the like. The pivoting of the first base portion relative to the second base portion allows the device to be more easily manoeuvred to the left or right.

The base may include a footrest such that an occupant of a chair being lifted may rest their feet on the footrest. The footrest is located so as to provide a comfortable leg position for the occupant of the chair, and further so as to prevent the legs of the occupant from being injured by or interfering with the operation of the device for example the raising of the support.

The base may further include control means for control of the device by the person operating it. The control means may include means for operating, for example the driven wheels, and any other means as required. Preferably, the control means includes a handle to allow a person to engage the device for its operation and in particular its movement over the underlying surface.

The device may further include braking means, the braking means acting upon the wheels to prevent movement of the device over the underlying surface. The braking means may take any suitable form.

In one embodiment, the person operating the device activates the braking means, via the control means. Alternatively, the braking means may normally be activated thereby preventing movement of the device, the braking means operable to be deactivated by the person operating the device via the control means to allow movement over the underlying surface. Preferably the braking means is deactivated by a person engaging the handle of the control means, such that if the person releases the handle the braking means will be reactivated preventing unwanted movement of the device. The device may further include any suitable power means, such as a battery or the like for powering, for example, the driving of the driven wheels, and any other means as required. The power means may include, for example, a rechargeable battery. The battery may be releasably retained on the device, so as to be removed from the device for recharging. Alternatively, the battery may be recharged while retained on the device.

Brief Description of the Drawings

The attached drawings show example embodiments of the invention of the foregoing kind. The particularity of those drawings and the associated description does not supersede the generality of the preceding broad description of the invention.

Figure 1 is a side view of the device according to the invention.

Figure 2 is a view of the device illustrated in Figure 1 as seen from below

Figures 3 to 5 show one embodiment of the support according to the invention

Figures 6a to 6c show steps in the operation of one embodiment of the engagement means according to the invention

Figures 7a and 7b show a perspective view of an alternative embodiment of the device according to the invention.

Figures 8 and 9 show an alternative embodiment of the support according to the invention

Figures 10 and 1 1 show further alternative embodiments of the support according to the invention

Figures 12 and 13 show a top view of the embodiments illustrated in Figures 10 and 1 1 Figure 14 shows the pivoting mechanism of the embodiment illustrated in Figure 1 1

Figure 15 is a view of means for titling the support of the device according to the invention

Detailed Description of the Drawings

Figure 1 shows a lifting device 10 according to the present invention. The device 10 includes a base 12 and a support 14 mounted to the base 12. Referring to figures 1 and 2, the base 12 is formed of a first base portion 16 and a second base portion 18, the first base portion 16 being pivotably connected to the second base portion 18. As shown, the first base portion 16 is pivotably connected to the second base portion 18 by a pin 20.

The first base portion 16 is provided with a pair of drive wheels 22. The drive wheels 22 are driven by any suitable means (not shown) for movement of the device 10 over an underlying surface S1. The second base portion 18 is provided with a pair of primary wheels 24. Further, the second base portion 18 is provided with a pair of auxiliary wheels 26. As shown, the auxiliary wheels 26 are provided on wheel supports 28, which are pivotally mounted to the second base portion 18. Further, the auxiliary wheels 26 are pivotalbly mounted to the wheel supports 28. The wheel supports 28 may be pivoted to extend laterally outward from the second base portion 16, such that the auxiliary wheels 26 are spaced laterally outward of the primary wheels 24 as shown. In this configuration, the auxiliary wheels 26 provide increased lateral stability to the second base portion 18. The wheel supports 28 may alternatively be pivoted to extend generally in the longitudinal direction of the device 10 such that the auxiliary wheels 26 are spaced laterally inward of the primary wheels 24. In this configuration the auxiliary wheels 26 do not interfere with the positioning of the second base portion 18 and the support 14 mounted thereto, beneath a portion of a chair C1. The device 10 further includes an actuator, in the form of a hydraulic cylinder 30. The ends 32, 34 of the cylinder 30 are pivotably connected to the first base portion 16 and second base portion 18 respectively. As shown, the extension or retraction of the cylinder 30 causes pivoting of the second base portion 18 relative to the first base portion 16 about the pin 20. Accordingly, the device 10 can be driven in a curved path, either to the left or right depending upon the direction of pivoting, thereby increasing the manoeuvrability of the device.

Referring to figures 3 to 5, the support 14 includes a support frame 36 having two beam supports 38, 40. The beam supports 38, 40 include a respective first beam member 42, 44 and a respective second beam member 46, 48. As shown, the beam supports 38, 40 are in the form of hydraulic rams, wherein the first beam member 42, 44 forms the cylinder of the ram while the second beam member 46, 48 forms the piston of the ram, such that the second beam member 46, 48 is axially displaceable relative to the first 42, 44.

The support 14 further includes an adjustment mechanism 50 in the form of a rack and pinion. Each of the support beams 38, 40 has a pair of toothed racks 52, 54 mounted thereto for engagement with a correspondingly toothed pinion 56. Rotation of the pinion 56 causes translation of the racks 52, 54 thereby adjusting the spacing of the beam supports 38, 40 relative to each other. The pinion 56 is driven by any suitable means (not shown).

The support 14 further includes a pair of leg supports 58. The leg supports 58 are pivotably mounted to the support 14 and can be pivoted between a deployed and a stowed position. In the deployed position, the leg supports 58 extend outward from the support 14 as shown in figures 1 and 5. In this position the leg supports 58 are operable to prevent the legs of the occupant from interfering with, or being injured by, the raising or lowering of the support 14. In the stowed position, the leg supports 58 do not extend outward from the support 14 as shown in figures 3 and 4. In this position, the leg supports 58 do not interfere with the positioning of the support 14 beneath a portion of the chair C1. The support 14 further includes retaining means (not shown) for retaining the occupant in the chair while the chair is being lifted. The retaining means may include a belt having an adjustable length, which extends from a portion of the support 14. The belt may be placed over the lap of the occupant of the chair secured to the support 14, and tightened to retain the occupant in the chair. The occupant can thereby be safely secured in the chair during lifting thereof.

As shown, the support 14 is mounted to the base 12 by a hydraulic cylinder 60. The hydraulic cylinder 60 provides a means for raising the height of the support 14 relative to the base 12. As can be seen in figure 1 , the height of the support 14 has been raised relative to the base 12 such that the chair C1 secured thereto and the occupant of the chair have been lifted from the underlying surface S1. As shown, the hydraulic cylinder 60 has raised the support 14 relative to the base 12 to a first height at which the chair and the occupant may be transported. The hydraulic cylinder 60 is further operable to raise the support 14 relative to the base 12 to a second height to aid the occupant of the chair to vacate the chair, while the chair is secured to the support 14. The hydraulic cylinder 60 is also operable to lower the height of the support 14 relative to the base 12. The support 14 may be lowered relative to the base 12 to return the chair to the underlying surface S1.

The device 10 further includes means (not shown) to rotate the support

14, relative to the base 12, preferably through 180°, more preferably, through 360°. Accordingly, a chair C1 may be lifted off an underlying surface S1 in a first orientation relative to the device 10, and returned to the underlying surface S1 in a second orientation relative to the device 10.

The device 10 further includes means (not shown) for tilting the support 14, relative to the base 12. The support 14 may be tilted relative to the base 12 prior to securing the support 14 to a chair having a particular configuration to assist in engaging the engagement means to that chair. Further, the support 14 may be titled relative to the base 12 subsequent to a chair being secured to the support 14 to aid the occupant of the chair to vacate the chair. Referring to figures 6a to 6c there is shown engagement means in the form of a pair of clamps 62, 64, for securing the support 14 to the chair. Each clamp 62, 64 is provided on a respective beam support 38, 40 and includes a first jaw 66, 68 and second jaw 70, 72. The each first jaw 66, 68 is disposed on a respective first beam member 42, 44 while each second jaw 70, 72 is disposed on a respective second beam member 46, 48.

Referring to figure 6a, the support 14 is shown positioned beneath a portion of a chair and between four legs L1 to L4 of the chair. The spacing of the beam supports 38, 40 is adjusted such that the width of the support 14 is less than the distance between opposing inside surfaces of respective left legs

L1 , L2 and right legs L3, L4 of the chair. Further, the second beam members

46, 48 have been axially displaced relative to the first beam members 42, 44 such that the spacing between the first jaws 66, 68 and second jaws 70, 72 of each of the pair of clamps 62, 64 is greater than the distance between opposing outside surfaces of respective front legs L2, L3 and back legs L1 , L4 of the chair.

Referring to figure 6b, the spacing of the beam supports 38, 40 has now been adjusted such that each beam support 38, 40 is now positioned generally adjacent respective left legs L1 , L2 and right legs L3, L4 of the chair. This positioning of the beam supports 38, 40 assists in the securing of the support 14 to the chair and increases the stability of the engagement by the engagement means. As shown, the first jaw 66, 68 of each clamp is now positioned substantially in engagement with an outside surface of respective front legs L2, L3 of the chair.

Referring to figure 6c, the second beam members 46, 48 have now been axially displaced relative to the first beam members 42, 44 such that the second jaw 70, 72 of each clamp 62, 64 is now positioned substantially in engagement with an outside surface of respective back legs L1 , L4 of the chair. In this position, the first jaws 66, 68 and second jaws 70, 72 have engaged the respective surfaces of the four legs L1 to L4 of the chair such that the support 14 is now secured to the chair.

It is to be appreciated that the engagement means may take any suitable form. For example, the jaws of each clamp could initially be positioned between rather than outside respective front and back legs of the chair, with the first jaws positioned substantially in engagement with an inside surface of respective front legs of the chair. By subsequent axial displacement of the second members to move the second jaws away from the first, the second jaws may then be positioned substantially in engagement with an inside surface of respective back legs of the chair, thereby securing the support to the chair. In another arrangement, the beam supports could extend substantially from the left hand side to the right hand side of the chair, rather than from the front to the back thereof.

As shown in figures 6a to 6c, the support 14 further includes a cover member 74 covering the support frame 36. The cover member includes a first, fixed portion 76 covering a first portion of the support frame and a second, extensible portion 78 covering a second portion of the support frame including the support beams 38, 40. The cover portion 74 may take any form and is preferably conformable, so as to conform to an underside of a chair to assist in securing the support 14 to the chair. The cover portion 74 may, for example, include a rubberised material.

Referring again to figure 1 , the base 12 further includes a footrest 80 such that an occupant of a chair being lifted may rest their feet on the footrest 80. The footrest 80 is located so as to provide a comfortable leg position for the occupant of the chair when the chair is lifted off the underlying surface S1. Further, the footrest, in addition to the leg supports 58, prevent the legs of the occupant from being injured by, or interfering with, the operation of the device 10 for example the raising of the support 14.

As shown in figure 1 , the base 12 also includes a control means 82. The control means 82 houses a battery (not shown) for powering the device 10. The control means 82 further includes a handle 84 for engagement by the person operating the device 10. As shown, the handle 84 is positioned to allow the person operating the device 10 to move the device 10 over the underlying surface S1. It will be appreciated that the control means 82 may further include such controls as are necessary to operate the various means of the device 10, for example the driving of the wheels and the raising and lowering of the support.

Figures 7a and 7b show an alternate embodiment of the invention. Lifting Device 1 10 includes a base 1 12 and a support 1 14 mounted to the base 1 12. The support 1 14 includes a platform 1 16, which is generally rectangular.

Referring to figure 8, there is shown an embodiment of the support 1 14 having alternate engagement means. The platform 1 16 further includes fixed clamping arms 118. The fixed clamping arms 1 18 extend outward from the platform 1 16 from one end thereof, generally perpendicular to the longitudinal extend of the platform 1 16. The support 1 14 further includes pivoting clamping arms 120. Pivoting clamping arms 120 are operable to pivot between a first position in which they extend generally parallel to the longitudinal extent of the platform 116 and a second position in which they extend generally parallel to the fixed clamping arms 1 18.

Referring to figure 9, the support 114 is shown positioned beneath a portion of a chair C1 , with the platform 116 between the left hand legs L1 , L2 and right hand legs L3, L4. For positioning of the support 1 14 beneath the chair, the pivoting clamping arms 120 are pivoted to the first position. As shown, the fixed clamping arms 1 18 are substantially in engagement with an outside surface of the front legs L2, L3 of the chair C1. The pivoting clamping arms 120 may then be pivoted so as to be substantially in engagement with an inside surface of the front legs L2, L3 of the chairC-1. In this position, the support 1 14 is now secured to the chair for lifting thereof.

As can be seen in figure 9, the pivoting clamping arms 120 include driven teeth 122. The support 1 14 further includes a worm screw 124. The driven teeth 122 are arranged to engage with the worm screw 124 such that the pivoting of the pivoting clamping arms 120 is driven by the worm screw 124.

Referring to Figures 10 and 1 1 , there are shown alternate embodiments of the support 214, 314. As shown, the support includes a platform 216, 316. The support 214, 314 further includes a first pair of pivoting clamping arms 220, 320 and a second pair of pivoting clamping arms 218, 318 (instead of the fixed clamping arms 1 18). In the embodiment shown in Figure 10, each of the of the pairs of clamping arms 218, 220 includes driven teeth 222. The driven teeth 222 of each of the pairs of clamping arms 218, 220 are driven directly by worm screw 224. Referring to figure 14, the pivoting mechanism of the embodiment illustrated in Figure 11 is shown. It can be seen that the first pair of pivoting clamping arms 320 includes driven teeth 322 which are directly driven by the worm screw 324 for pivoting of the first clamping arms 320. In addition to the driven teeth 322, each of the first pivoting clamping arms 320 further includes driving teeth 326. Driving teeth 326 engage teeth 328 on the second pivoting clamping arms 318 such that pivoting of the first clamping arms 320 drives pivoting of the second pivoting clamping arms 318.

Referring to Figures 12 and 13, there is shown a top view of the embodiments of the support 214, illustrated in Figure 10. In Figure 12, each of the pairs of pivoting arms 218, 220 have been pivoted so as to be substantially parallel to the longitudinal extent of the platform 216. In this position, the first clamping arms 220 extend generally beneath the platform 216, while the second clamping arms 218 extend generally outward from the platform 216. In this position the support 214 may be positioned beneath a portion of a chair to be lifted. In Figure 13 each of the pairs of pivoting arms 218, 220 have been pivoted so as to extend substantially outward of the platform 216, toward a position in which they might engage a chair to be lifted.

Referring to figure 15, there is shown a side view of the support 1 14. As shown, the support 1 14 is pivotably mounted to a hydraulic cylinder 126 about an axis 128. The support 1 14 further includes a tilting cylinder 130 operable to drive the pivoting of the support 1 14 about the axis 128. The support 1 14 may thereby be titled relative to the base 112.

It will therefore be appreciated that the lifting device according to the invention provides a simple means for lifting a person, particularly a person of limited mobility from a seated position. Further, the device obviates the need for those aiding the lifting to manoeuvre the person to be lifted prior to lifting using the device It will further be appreciated that a device according to the invention provides a means for lifting a person, particularly a person of limited mobility, whereby the risk of injury to those who perform the lifting operation is advantageously reduced.

The invention described herein is susceptible to variations, modifications and/or additions other than those specifically described and it is to be understood that the invention includes all such variations, modifications and/or additions which fall within the spirit and scope of the above description.

Claims

The Claims Defining The Invention Are As Follows:

1. A lifting device for lifting a chair having an occupant, the device including; a base, a support mounted to the base and positionable beneath a portion of the chair, the support having engagement means operable to releasably engage a portion of the chair and secure the support to the chair; and means for raising the height of the support relative to the base for lifting the chair and the occupant off an underlying surface.

2. A lifting device according to claim 1 , wherein the means for raising the height of the support also provides a means for lowering the height of the support relative to the base from a raised position.

3. A lifting device according to claim 2, wherein the means for raising the height of the support includes at least one lifting cylinder or piston, which is extended to raise the height of the support relative to the base and retracted to lower the height of the support relative to the base.

4. A lifting device according to claim 3, wherein the cylinder or piston is actuated hydraulically.

5. A lifting device according to claim 1 or 2, wherein the means for raising the height of the support includes a first and second lifting cylinder or piston.

6. A lifting device according to claim 5, wherein the lifting device further includes a support arm, the first piston being arranged between the base and the support arm and the second piston being arranged between the support arm and the support, the first piston being operable to raise the height of the support arm, and indirectly, the support, relative to the base, and the second piston being operable to raise the height of the support relative to the support arm.

7. A lifting device according to any one of the preceding claims, wherein the support is rotatable relative to the base

8. A lifting device according to claim 7, wherein the support is rotatable relative to the base through at least 180°.

9. A lifting device according to claim 8, wherein the support is rotatable relative to the base through 360°.

10. A lifting device according to any one of the preceding claims, wherein the lifting device is configured for lifting the support relative to the base to a first height for transporting a chair, and at least one further height for aiding an occupant to vacate the chair.

11. A lifting device according to claim 5, or any one of claims 6 to 10 when directly or indirectly dependent on claim 5, wherein one of the first and second cylinders or pistons is operable to raise the support to a first height for transporting of the chair, and the other of the first and second cylinders or pistons is operable to raise the support to a second height to aid the occupant of the chair in vacating the chair.

12. A lifting device according to any one of the preceding claims, wherein the support includes a platform for engaging the underside of the chair to be lifted.

13. A lifting device according to claim 12, wherein the support includes a support frame for engaging the underside of the chair.

14. A lifting device according to claim 13, wherein the support frame includes two support beams extending substantially in parallel to each other.

15. A lifting device according to claim 14, wherein the support frame includes adjustment means for adjusting the spacing between the support beams to enable positioning of the support beneath a portion of the chair.

16. A lifting device according to claim 15, wherein the adjustment means includes a hydraulic cylinder.

17. A lifting device according to claim 15 when dependent on claim 14, wherein the adjustment means includes a rack and pinion mechanism, with each of the support beams including at least one toothed rack, and the support further including at least one correspondingly toothed pinion for engagement with and driving of each toothed rack.

18. A lifting device according to claim 14, or any one of claims 15 to 17 when directly or indirectly dependent on claim 14, wherein each of the support beams includes a first beam member and a second beam member, the first and second beam members having substantially parallel axes, and the second beam member being moveable relative to the first beam member along its axis, such that the length of the support beams may be varied.

19. A lifting device according to claim 14, or any one of claims 15 to 18 when directly or indirectly dependent on claim 14, wherein the support includes a cover member covering the support frame, the cover member including a first, fixed portion covering a first portion of the support frame and a second, extensible portion covering a second portion of the support frame, the second portion of the support frame including the support beams.

20. A lifting device according to any one of the preceding claims, the support further including leg supports for supporting the legs of the occupant of the chair during lifting of the support relative to the base.

21. A lifting device according to claim 20, wherein the leg supports are pivotably mounted to the support so as to be pivotable from an active or extended position when the device is being used to lift a chair to an inactive or retracted position when the device is not being so used.

22. A lifting device according to any one of the preceding claims, the support including retaining means for retaining an occupant of a chair in the chair while the chair is being lifted.

23. A lifting device according to claim 22, the retaining means including a belt extending from the support.

24. A lifting device according to any one of the preceding claims, the engagement means including at least one clamp provided at a periphery of the support, and operable to be clamped to the legs of a chair when the support is positioned beneath a portion thereof.

25. A lifting device according to any one of the preceding claims, the support including at least one strap for releasably engaging a portion of a chair.

26. A lifting device according to claim 25, the support including a plurality of straps enabling the support to be engaged with the chair at more than one location, with at least one strap engaging a portion of the chair, and another strap passing over the lap of the occupant of the chair to form part of a retaining means for retaining the occupant while the chair is being lifted.

27. A lifting device according to any one of the preceding claims, the device including means for tilting of the support relative to the base.

28. A lifting device according to any one of the preceding claims, the base including at least one wheel, roller and/or caster for movement of the device over the underlying surface.

29. A lifting device according to claim 28, wherein at least one wheel, roller and/or caster are driven.

30. A lifting device according to claim 28 or 29, wherein at least one wheel, roller and/or caster are pivotable about a vertical axis.

31. A lifting device according to any one of claims 28 to 30, the base including a first base portion and a second base portion, the first base portion being pivotably connected to the second base portion, and each of the first and second base portions including a pair of wheels, rollers or casters.

32. A lifting device according to claim 31 , the second base portion including a pair of auxiliary wheels, rollers and/or casters spaced laterally outward of the wheels, rollers and/or casters of the second base portion.

33. A lifting device according to any one of the preceding claims, the base including a footrest.

34. A lifting device according to any one of the preceding claims, the base including control means for control of the device by a person operating it.

35. A lifting device according to claim 29, or any one of claims 30 to 34 when directly or indirectly dependent on claim 29, including braking means, the braking means acting upon at least one wheel, caster and/or roller to prevent movement of the device over the underlying surface.