Abstract: A patient transport system includes a patient table, a self-propelled support vehicle having means for loading the patient table and means for unloading the patient table, a patient diagnosis and/or therapy station, and a control means for controlling an operation of the at least one self-propelled support vehicle. A patient disposed on the patient table is presentable at the patient diagnosis and/or therapy station by controllably moving the support vehicle. The means for unloading the patient table are provided to unload the patient table from the support vehicle into a determined position within the patient diagnosis and/or therapy station. The means for loading the patient table are provided to load the patient table from the determined position within the patient diagnosis and/or therapy station into a determined position on the support vehicle.

Abstract: The invention is directed to a patient transfer system with associated patient support frames, lift carts, lifts, carts, and other accessories for use therewith. The support frames of the present invention as depicted in the exemplary embodiments are designed to: (a) provide rigidity (exoskeleton) to the human body for positioning to provide stability for purposes of transferring, lifting and/or transporting the subject via a mobile device, such as a powered lift device; (b) a male/female coupling for coupling to a tine or other carriage mechanism of a lifting device thereto for the purpose of moving or lifting the subject; and/or (c) be used as a support or frame that will interact with the body as an exoskeleton to aid with the activities of daily living.

Abstract: A telescopic rail and carriage assembly for suspending a patient lift. The carriage has a downward projection to which the patient lift is to be connected. The telescopic rail has an inner rail section and an outer rail section. The outer rail section is provided with first longitudinally extending interior support surfaces for supporting a lower set of wheels of the carriage. The inner rail section is provided with second longitudinally extending interior support surfaces for guiding and supporting an upper set of wheels of the carriage. In the extended state, the carriage is guided by the either the first or the second longitudinally extending support surfaces except where the first and second rail sections overlap. In the overlap, the wheels of the carriage are supported by both the first and second longitudinally extending interior support surfaces.

Abstract: A system for transferring medical patients utilizes the concept of creating a “hollow space” between the patient and the surface on which he or she is supported. A patient support material mounted to a rigid frame positioned about a bed or other hospital furniture can have slots or openings extending laterally inward from at least one side of the patient support material and oriented substantially perpendicular to a line running from the head of the bed to the foot of the bed. The slots allow respective tines of a transport device, or straps from a patient transfer chair or device, to be inserted beneath a patient lying on the patient support material such that the tines or straps (or other elongated patient support/transfer components) can be lifted above through the slots and thus transfer the patient from the patient support material to the tines or straps of the patient transfer/transport device.

Abstract: A hospital bed apparatus includes a supporting frame, a lifting mechanism, and a horizontally moving mechanism; the lifting mechanism includes two horizontal rods on two sides of a hospital bed, and a sheet is disposed between and connected to the horizontal rods; either one of the horizontal rods can be lifted so as to turn and reposition the patient on the sheet; the horizontally moving mechanism includes linearly displaceable transverse rods, and connecting rods pivoted to the transverse rods and the lifting mechanism; the sheet and the horizontal rods of the lifting mechanism will be moved outside of the hospital bed when the horizontally moving mechanism is actuated after the sheet have been lifted off the hospital bed together with the horizontal rods; thus, the patient can be shifted to another hospital bed.

Abstract: A stretcher includes a patient support, a base, a plurality of support members supporting the patient support relative to the base, which are adapted and arranged to raise or lower the base relative to the patient support, and a locking mechanism. The locking mechanism is actuatable between a locked position wherein the locking mechanism locks the support members at a fixed height and an unlocked position wherein the support members are released from being locked at the fixed height so that the base or the patient support may be moved relative to the other. Further, the locking mechanism is configured to provide a stop for the support members and absorb energy from the support members are release and the support members engage the stop.

Abstract: A patient lift has a base extending in a forward direction, and a mast mounted relative to the base. The mast includes a hinge configured to allow the mast to be pivoted relative to the base between an upright operative position and a folded position, wherein when the mast is in the folded position the mast is substantially parallel to the base and extends in the forward direction. A latch mechanism is configured to hold the mast in the folded position when the latch mechanism is locked, and to allow the mast to be returned to the upright operative position when the latch mechanism is released. The latch mechanism is configured to automatically lock when the mast is moved to the folded position.

Abstract: The subject of the invention is a mechanical lifting system with seat which enable the disabled people with paralysis or paresis of lower limps to stand up from the wheelchair and without excessive energy expenditure take upright position in standing frame and came back to the wheelchair. This mechanical lifting system can be used in a kind of walking frame, static standing frame or mobile standing frame and is very useful in rehabilitation of disabled people.

Abstract: A wheelchair and an examination table is provided wherein there is provided a connector or connector assembly for connecting the wheelchair to the examination table. Once connected to the examination table, the wheelchair and patient sitting therein can be elevated, after which side frames of the wheelchair can be removed in order to facilitate examination of the patient. In addition, once elevated and the side frames removed, with the aid of a movable back that forms a part of the examination table, the back of the wheelchair can be reclined or positioned in various positions to facilitate examination and procedures.

Abstract: A telescopic rail and carriage assembly for suspending a patient lift. The carriage has a downward projection to which the patient lift is to be connected. The telescopic rail has an inner rail section and an outer rail section. The outer rail section is provided with first longitudinally extending interior support surfaces for supporting a lower set of wheels of the carriage. The inner rail section is provided with second longitudinally extending interior support surfaces for guiding and supporting an upper set of wheels of the carriage. In the extended state, the carriage is guided by the either the first or the second longitudinally extending support surfaces except where the first and second rail sections overlap. In the overlap, the wheels of the carriage are supported by both the first and second longitudinally extending interior support surfaces.

Abstract: A wheelchair and an examination table is provided wherein there is provided a connector or connector assembly for connecting the wheelchair to the examination table. Once connected to the examination table, the wheelchair and patient sitting therein can be elevated, after which side frames of the wheelchair can be removed in order to facilitate examination of the patient. In addition, once elevated and the side frames removed, with the aid of a movable back that forms a part of the examination table, the back of the wheelchair can be reclined or positioned in various positions to facilitate examination and procedures.

Abstract: This invention is directed towards a patient single surface system, PS3, which is a next generation system solution for patient accommodation, diagnosis, treatment, transfer and transport. PS3 provides a single surface for the patient to remain on from the trauma site through diagnosis, treatment and convalescence. Needs addressed by the PS3 system include improved patient treatment through reduction in time to treatment, reduced or eliminated unnecessary patient movement and injury, as well as improved comfort throughout treatment and convalescence. In addition, the PS3 system solves significant economic considerations.

Abstract: A transferring device for a bed, placed on a bed plate, on top of or below a mattress, comprises a first inflatable bag; placed on the bed plate and having in an inflated state a triangular shape, with a inner and outer edges having different heights; a second inflatable bag; placed on the first inflatable bag and having in an inflated state a triangular shape, with a inner and outer edges having different heights; and a compressor for inflating and deflating the first and second inflatable bags.

Abstract: A wheelchair and an examination table is provided wherein there is provided a connector or connector assembly for connecting the wheelchair to the examination table. Once connected to the examination table, the wheelchair and patient sitting therein can be elevated, after which side frames of the wheelchair can be removed in order to facilitate examination of the patient. In addition, once elevated and the side frames removed, with the aid of a movable back that forms a part of the examination table, the back of the wheelchair can be reclined or positioned in various positions to facilitate examination and procedures.

Abstract: A load sensing safety device comprises a pulley shaft carrying a pulley. The pulley, in turn, carries a belt that effectuates movement of the patient lift boom. A biasing element applies a spring force against the pulley shaft to move the pulley shaft in a first direction. A switch that opens and closes responsive to movement of the pulley shaft, whereby the switch opens where the pulley shaft is moved to a first position by movement of the spring in the first direction.

Abstract: An apparatus for repositioning bedridden patients with: a base, vertical and horizontal movements, and lifting portion; telescoping legs extending outward from the base with wheels affixed to each leg; detachable clamps affixed to each leg and capable of removeably attaching to a bed; the horizontal movement containing a roller and belts actuated by a gear and crank assembly coupled to the vertical movement portion; the vertical movement having two lifting units with first and second pistons coupled to the inside of each of the units and a hydraulic pump and controller for the actuation of the hydraulic pump and the upward and downward movement of the pistons; the lifting portion comprising a telescoping lifting arm with a lead screw and a crank for extending or retracting said lifting arm and with a lateral movement portion coupled to the top of the vertical movement and the lifting portion.

Abstract: A system for repositioning a patient. The system may be coupled to a structural support system or framework that extends above a bed. The system may be translated transversely and longitudinally and placed in one of multiple locations above the bed.

Abstract: A patient-support apparatus includes a patient-support deck coupled to first and second lift systems configured to lift the patient-support deck relative to the floor. The lift systems each include a pair of supports and a carriage coupled to the patient-support deck and suspended from the supports by tethers which are wound and unwound to raise and lower the patient-support deck.

Abstract: A system for assisting a seated person to stand that may include a walker and a lifting arm attached to the walker that extends in an approximate vertical direction from the walker. The walker may include two front legs and two rear legs, and the lifting arm may extend telescopically from one of the front legs.

Abstract: A portable lifting apparatus for lifting and transferring of heavy objects. The lifting apparatus having a load-supporting platform which can be moved both vertically and rotated about the vertical axis of an upwardly extending lifting column. The lifting apparatus further includes an outrigger linkage coupled to the lifting column and is provided with a load support coupled to a retractable pulley. The lifting column is attached to a base and is normally prevented from rotating relative thereto.

Abstract: A rolling chassis supports dual lifting beams pivotably mounted on adjustable supporting pins. The beams are pivoted by rollers raised by dual driving piers. Each beam carried a pair of blocks for a rope running from a locking system on the chassis to one side of an upper harness, and another pair of blocks for a rope running from a locking system on the chassis to one side of a lower harness. A retractable knee pad assists lifting a patient from sitting to standing position as the beams pivot and retract the cables.

Abstract: The present invention concerns a hoisting device including a hoisting module which is replaceably connected with a coupling arrangement for a trolley which is mounted in a ceiling-mounted rail arrangement, where the coupling arrangement is provided in two sections, where the first section is mounted on the hoisting module, and the second section is mounted in connection with the trolley, and where the hoisting module includes a lifting strap arranged for rolling up and unrolling and for fastening a lifting bracket and/or lifting canvas, where the first section of the coupling arrangement is mounted releasably on the hoisting module, that the first section and the second section of the coupling arrangement are mutually connected with a wire connection which is connected with a winding arrangement that includes means dimensioned for lifting the weight of hoisting module, lifting bracket and lifting canvas.

Abstract: As the obesity rate climbs nationwide, obese and morbidly obese patients will continue to pose special lifting challenges to the healthcare industry. Obesity among American adults has nearly doubled during the past two decades. One in 80 men weights >300 pounds and one in 200 women weights >300 pounds. Getting assistance is crucial when moving these patients. With these rising numbers, have come the numerous complications relating to medical treatment for these bariatric patients. Healthcare providers must consider the additional costs associated with handling of the bariatric patient along with safety issues relating to both the bariatric patient and caregiver. Also, moving extremely obese patients can prove to very dangerous or even fatal. The most economical assistance to move bariatric patients to and from the hospital bed can only be provided by some mechanical aid.

Abstract: A method and apparatus is disclosed for sensing when a person is disposed on or arises from a support that flexes or sags when a person is disposed thereon. Such supports include beds, supports for a mattress or a seat, such as a sling-type seat found on wheelchairs. In one embodiment, an assembly is positioned beneath the support and includes a sensor. The sensor indicates when tension on the assembly exceeds a certain amount which is indicative of sagging of the support. The assembly may be adjustable in length to maintain proper tension in the absence of sag. The sensor may be a switch that includes a plunger which operates against the bias of a biasing member which either completes or interrupts an electrical circuit in response to tension placed on the assembly due to sagging of the support. In another embodiment, the assembly may be at least partially elastic. In yet another embodiment, a strain gauge may be employed to detect stretching of the assembly due to sagging of the support.

Abstract: In a lift and transfer device and method, a patient support assembly supported on a lift on a wheeled platform includes a main support arm pivoted to the lift. First and second transversely extending support arms respectively carrying a back support section and a leg support are cantilevered from the main support arm. The main support arm is positioned for lifting the patient from a bed. The main support arm is rotated from a first to a second angular position for lowering a patient to a wheelchair. First and second pivot arms each have an upper end pivotally supported to the back support section and a lower end having a torso grip pad positioned adjacent one side of the patient. Horizontal force applied by each torso grip pad and friction provide patient support. Further device forms are provided for bariatric patients and for use with other types of lifts.

Abstract: A loading/unloading unit is formed with an oblique surface and an upper surface having contact areas to come into contact with a cared person, and the oblique surface and the upper surface of the loading/unloading unit are vibrated in a load direction and an unload direction upon loading the cared person on the loading/unloading unit or unloading the cared person from the loading/unloading unit. Therefore, a transfer apparatus can safely transfer the cared person while preventing an occurrence of the entanglement of the hair and the like of the cared person.

Abstract: A patient bed is provided for transporting and/or positioning a patient. The patient bed has a bed area provided for receiving a patient. The patient bed is flexible at least in the bed area in such a way that the patient bed can be rolled up around a part of the patient bed. The patient bed has at least one transport mount for acting on by a transporter, and the patient bed is designed to be transported via the at least one transport mount when loaded with a patient. The patient bed has a plurality of reinforcing fibers, which are flexible and tension-proof, wherein each of the reinforcing fibers passes through the bed area and is operatively connected to at least one of the at least one transport mount in such a way that a force acting on the bed area can be transmitted at least partially to the at least one transport mount.

Abstract: A patient lifting device is provided. The patient lifting device includes two side limbs connected to a suspension mounting for suspending the device from a hoist. Each side limb includes a support bar including patient support elements. The patient support elements include a pair of side pads for engaging beneath the armpits of a patient and against sides of the patient's ribcage, and a patient upper leg or posterior support means. The two support bars connect together with an assembly from which the patient upper leg or posterior support means depends. Each support bar is pivotally mounted about a pivotal axis defining a balance axis about which the moments imparted by the weight of the patient's upper body through the side pads and by the weight of the patient's lower body through the upper leg or posterior support means can react against one another in an equal and opposite fashion.

Abstract: A raising and lowering device, particularly suitable for incapacitated human or animal patients. The device includes a load carrying support having at least one elongated arm including a proximal end section and distal end section. The arm is pivotable on the device at the proximal end section and movable by pivoting between an operating position in which the support is positioned for carrying said load, and a stored position in which the arm forms a graspable handle allowing an operator to carry the device. The invention also relates to components suitable for use with the device.

Abstract: An invalid hoist comprises a support 10, an arm 12 pivotally connected to the support 10, drive means for driving the arm 12 for pivotal movement relative to the support 10, and brake means 18 independent of the drive means to apply a braking force to the arm 12 in the event that movement thereof occurs at a speed grater than a predetermined speed.

Abstract: A hoist pivotally connecting mast 1 to lifting arm 2, by a mechanism comprising a link 5 pivoting about a fixed pivot 8 on the mast 1 and a moving pivot 6 on the lifting arm 2. A restraining link 9 between a pivot 10 on the mast 1 and actuator attachment point 11 on the lifting arm 2 restricts the movement of link 5. The second link 9 acts as a stabilizer allowing the pivot 11 on the lifting arm 2 to move only through a set arc, determined by the length of the link 9 and the position of the pivot 10 on the mast 1. With the moving pivot according to the invention, the spreader bar attachment point 7 has a greater traveling distance than if it were simply pivoted about pivot 8 as with conventional hoists.

Abstract: A hoist and associated method for erecting the hoist for assisting movements of disabled persons. The hoist has a fixed-length stanchion that is supportable at opposing longitudinal ends thereof by first and second support members that are, in turn, fixed to a facility structural framework. The stanchion is removable from the support members without detaching any of the support members from the facility structural framework.

Abstract: This invention describes a transfer stretcher, harness and method designed to lift, transfer or support a person, more specifically a heavy weight, large size (oversize) person. Stretchers are generally used by hospitals or by rescue/emergency units to lift or carry a person from one location to another. The transfer stretcher covered by the present invention is made of a supporting canvas equipped with lifting straps and rings, a removable washable comfort cloth, and maybe used with a removable safety harness that can be used with a stretcher basket and a sling frame. The transfer stretcher can be used to move a body manually with the help of several persons, or in combination with various lifting equipment.

Abstract: A patient movement system comprises a rotatable section coupled to a frame that moves in a horizontal plane. A hoist assembly is coupled to the rotatable section and spins relative to the rotatable section. The hoist assembly may be positioned by the rotatable section. The hoist assembly includes a first motor coupled to a first linearly moving pulley by a first linkage. The first linkage includes horizontal and vertical sections of travel, whereby the vertical sections of travel decrease when the horizontal sections of travel increase. The hoist assembly includes a second motor coupled to a second linearly moving pulley by a second linkage. The second linkage includes horizontal and vertical sections of travel, whereby the vertical sections of travel are decrease when the horizontal sections of travel increase. The hoist assembly may include additional pulleys to guides the first and second linkages.

Abstract: A moving device (1) capable of being operated easily and safely to move a person between various types of beds and chairs by supporting the femoral region and backbone of a person to be moved instead of by suspending the person to be moved by a belt or supporting the axillas and knees of the person, comprising a body frame (4) having a pair of right and left front wheels (2) and rear wheels (3) and having an open rear side, a column (14) erected on the body frame, a pair of right and left side seat parts (32) provided on a pair of right and left side arms (31) fixed to the column, a handrail frame body (46) fixed to the column and having an open rear side, a backbone supporting part (48) disposed at the rear of the seat parts, and a lifting mechanism capable of lifting the seat parts vertically, wherein the arms are formed in a crank-shape and connected pivotally to the column through longitudinal shafts positioned at the front of the knees of the person to be moved, and the seat parts are rotated eccentrical

Abstract: According to the present disclosure, a transfer top adapted to carry a patient is transferable between a mobile base and a docking station in a hospital room. Thus, instead of transferring a patient between a stretcher and a hospital bed, the entire transfer top with the patient thereon is transferred between the mobile base and the docking station.

Abstract: An invalid person transfer system that has a rectangular frame suspended from a dolly moving on a track on the ceiling. There are left and right support columns that have gear boxes attached to their lower ends. The gear boxes each have at their ends attached thereto pivotal frame members that are connected to each other by a multiple of connecting rods. From the gear boxes conveyor belts are driven to front rollers that form a forward edge between the pivotal frame members in a return manner. The conveyor belts can be driven by either belt drives or gear drives from the gear boxes. In operation, a patient sits on a support and the fronts of each of the frame members move under the patients assisted by the conveyor belts from each side. When the fronts of the frame members are in a close proximity, the patient is sitting on the conveyor belts and then be transported or transfer to a different location without any assistance from an attendant.

Abstract: A patient lifting apparatus is provided that attaches to a bed frame having a plurality of legs and a headboard. The apparatus includes an upright member, a boom mechanically associated with the upright member, an upper support bar that extends across the bed frame and secures the upright member to each side of the headboard, and a lower support bar that extends across the bed frame and secures the upright member to the legs. The upright member is supported for rotation about a vertical axis by upper and lower bearings on the upper and lower support bars, respectively. A telescoping foot member extends from the lower support bar and is movable between a stored position and an extended position for stabilizing the lifting apparatus. A support arm extends from a lower end of the upright member and rotates along with the upright member to transfer vertical forces into the floor.

Abstract: A chair for transporting a person from a first location to a second location along a rail in response to an input provided to a control for a hoist and motorized conveyor by the person. The chair includes first and second seat portions that are pivotally attached to a frame and connected by a linkage arrangement to a lever arm. The hoist moves the chair toward a fixed surface while surrounding the person and as the person moves the lever arm from a first position, the first and second seats portions move from a vertical position to horizontal position under the person. Thereafter, the lever is locked in a fixed position and the hoist activated to raise the chair to allow the chair to be moved by the motorized conveyor along the rail.

Abstract: The present invention discloses a portable lift seat to raise or lower a physically challenged user from a position on the floor to a standard height seated position or to a near standing position or vice versa. The lifting and lowering mechanism includes a seat with a rigid bottom supported by a seat support means which is attached to a lifting column standing upon a base fame. The lifting column is powered by an electric motor which may be controlled with a handheld control device. Alternatively, the lifting column may be powered by a manual crank. The base unit is equipped with wheels which engage for portability.

Abstract: Disclosed herein is a patient transfer device comprising lifting arrangement positionable adjacent a patient and movable between a first position and a second position, and support arrangement for supporting the patient. The support arrangement is attachable to the lifting arrangement along a number of anchor locations thereon, the anchor locations including a pair of central anchor locations, a first pair of outer anchor locations on one side of the pair of central anchor locations and a second pair of outer anchor locations on an opposite side of the central pair of anchor locations; the support arrangement including a pair of central contact locations near a central location on the body of the patient, a first pair of outer contact locations on one side of the pair of central contact locations and a second pair of outer contact locations on an opposite side of the central pair of contact locations.

Abstract: A mobile, rehabilitative walker is configured for use outdoors on an irregular or rough support surface. The walker includes a support frame, configured for supporting a person in an upright position, having a plurality of frame members defining an open rear end and an interior space sized for receiving a wheelchair. A plurality of wheels are rotatably coupled to the support frame, and configured for multidirectional movement on the support surface. A support harness is vertically suspended from a rotatable upper rail of the support frame. A crank mechanism is coupled to the upper rail, and configured to rotate the upper rail to draw the support harness upward. The crank mechanism includes a crank handle located near the rear end of the support frame to facilitate rotation of the upper rail.

Abstract: An arrangement in a bed (1) intended for a disabled person and comprising a horizontally rotatable multi-sectional bed base part (3a, 3b) supporting a mattress, the base part being convertible into a seat part (3b) and a backrest part (3a), together with a fixed bed base part (3c). The arrangement furthermore comprises a lifting mechanism 82a) connected to the rotatable bed base parts (3a, 3b) supporting the mattress, the mechanism 82a) being operatively connected to a safety hook (A), that can be connected to a lifting sling, for example, which is worn by the person.

Abstract: A system and method for adjusting a person's upper torso in particular, the forearms to a generally parallel position to a floor surface in relation to a work product. A lifting apparatus includes a base support for moving the lifting apparatus horizontally on a floor surface. The base support may include a plurality of wheels being lockable. A platform having a multilayer construction for supporting at least a user thereon. The multilayer construction having a non-slip layer outer layer, a compressible inner layer, and a base layer. A vertical lifting system coupled to a platform and coupled to a base support. The vertical lifting system is configured to vertically move the platform through a plurality of heights above a floor surface. The vertical lifting system may have a pair of laterally mounted hollow stanchions in which each stanchion includes a axially rotatable threaded rod for matingly receiving a gear which is mounted to a drive shaft that provides rotary movement to the gear.

Abstract: Support method and apparatus for providing a secure and stable method for a user/patient to transfer a body part, such as a foot, into and out of a bed independently, and thus enhance in-bed mobility. The support for the body part is by a rest member having an associated expandable member. The rest member is a platform configured to the body part being supported, and the expandable member is a bellows adhered to the platform and expandable by a compressor. In the method a body part is positioned on the rest member, which is expanded with the body part thereon.

Abstract: An apparatus for weighing a person having an inner mast attached to a base and an outer mast slidably disposed over the inner mast. A platform is attached to the outer mast wherein the platform accepts the feet of the person. The apparatus includes a load cell attached to the inner and outer mast proximate the top end of the outer mast such that when the person stands on the platform the platform transfers the weight of the person from the outer mast to the load cell such that the person's weight can be determined.

Abstract: A device for transferring medical patients from one table, bed, or gurney to another is disclosed. The device includes a slide board which is slid beneath the patient while the patient is on the gurney. The slide board is then connected to a winch which rests on a cart and can be activated in a controlled manner. The action of the winch pulling the slide board in a horizontal fashion makes the transfer of the patient simple and easy. The cart is designed to be mobile, but includes hooks for fixing the cart to the floor so that it may withstand the stress induced by the retraction of the winch cable.

Abstract: The present invention includes a patient transport apparatus adapted to support a patient in a plurality of positions including a standing position and a seated position.

Abstract: The invention is directed to an invalid patient transport system from point A to point B. The system is suspended from a ceiling and can move relative thereto in a first movement The system has a second movement to be able to turn relative to the ceiling in different directions. The transport system further has a third movement and that is an up and down movement relative to the ceiling. The system further has a fourth movement and that is to move a seating assembly under a patient and between the location the patient is sitting or reclining on.

Abstract: The invalid lifting device comprises a first mast upstanding from a first elongate chassis member and a second mast upstanding from a second elongate chassis member which is parallel or substantially parallel to the first chassis member. The lifting device also comprises a lifting arm supported by and extending between the first and second masts, the lifting arm comprising two parts pivotable relative to one another so that the distance between the masts can be varied. One part is supported by the first mast and the other part is supported by the second mast. Power operated means are provided for moving the two chassis members towards and away from one another. Each part of the lifting arm comprises a parallelogram linkage to maintain the chassis members in parallel or substantially parallel relationship as the two chassis members are moved towards and away from one another.