Abstract: A height and tilt adjustable wheelchair support has a stationary base (30) with a main support leg (38) thereon. A platform (50) receives a wheelchair (20) and the platform (50) is connected to the main support leg (38) via a chassis (70), vertically movable via a length extendable cylinder (78) connected between the base (30) and the chassis (70). A second length-adjustable cylinder (88) rotates the wheelchair supporting platform (50) relative to the chassis (70) around a pivot (92) such that the wheelchair (20) can be raised, lowered, or tilted, via independent controls.

Abstract: Portable car hoist convertible to a trailer which has wheels for towing a vehicle. The hoist includes a trailer with a suspension, a wheel assembly, a base frame assembly, a liftable platform assembly, and a lift apparatus. A foldable ramp, a platform, and extension channels support a vehicle to be lifted, and a chock assembly retains the vehicle on the platform. A safety latch prevents accidental lowering of the platform assembly.

Abstract: A rotary hoist generally comprising a vertically extending shaft, a tubular housing telescoped over and rotatably supported on the shaft, a boom pivotally secured to the tubular housing and a jack pivotally secured between the housing and the boom. The shaft is supported by a leg socket member with elongated legs. The rotary hoist may be disassembled for storage or shipping.

Abstract: The scissor lift has two parallel sets of legs. Each set has one end of an inner leg pivoted on a base and the other end slideable on the elevating platform. One end of the outer leg of each set is pivotally connected to the platform while the other end slides on the base. The mid portion of the legs are pivotally connected on a pin which also supports a crank which can rotate about 90.degree. between a first generally horizontal position in which the actuated end of the crank is eccentric to an imaginary line connecting the pivot pin and the pivot of a ram which actuates the end of the crank. Initial actuation of the crank 90.degree. raises the pivot pin and the actuated end of the crank to increase the mechanical advantage of the ram. The angle of the ram now has adequate uplift to be as effective as the prior art while requiring about 1/2 the storage height. A stop bar is pivoted on the pivot pin and has a free end or tail slideable along the base as the pivot pin rises.

Abstract: A castered, low-profile, hydraulic lift assembly including a pivoting lift arm supporting a plurality of detachable transition arms and lift heads. Slip couplers, including linch pins and set screws mating with the arms and lift heads, adjustably position the proper head in overlying or underlying relation to the workpiece. The lift heads, which include workpiece securing hooks, support yokes, chains and support harnesses, slip mount to a slotted end of the outermost arm.

Abstract: The present invention defines a power lift-assist apparatus that includes a base platform and a load-support platform adapted to move in parallel relation to the base platform. Mounted to the base platform is a pneumatic motor comprising a substantially stationary piston formed with an internal pressure chamber therein and a slidable cylinder which is provided with a pair of cam rollers that are positioned to engage respective cam recesses formed in a carriage-lift framework whereby the load-support framework is activated from a retracted position to a fully extended position.

Abstract: A motor vehicle lift comprising in combination:a pair of base longitudinal members (1) for its support on and/or securing to the floor,a pair of first uprights (2) hinged lowerly to said longitudinal members (1),a pair of second uprights (4) hinged lowerly to said longitudinal members (1) and upperly to said first uprights (2) at an intermediate point thereof,a pair of vehicle lifting runways (6) hinged to the upper end of said first uprights (2) and formed in several separate parts which are kept substantially aligned when the lift is lowered,a pair of actuators (17) acting so to vary the reciprocal contained angle of said pairs of first uprights (2) and second uprights (4), for raising the lift, anda pair of members (15,15') interposed between said first uprights (2) and the portion (8) of runways (6) hinged to said first uprights (2) to check their reciprocal contained angle during the raising of the lift,the hinging between a pair of said uprights (2,4) and said longitudinal members (1) being of such a ty

Abstract: A height adjusting mechanism for a physical therapy bench has great lifting height due to levers extending at an angle with each other in one end position which are made to coincide approximately midway in their movement, said movement being permitted to continue in said levers passing each other and in their other end position again extending at an angle with each other.

Abstract: A portable lifting jack with ram, engine stand and transmission cradle. The jack is comprised of a boom for hoisting objects, an engine stand, transmission cradle, and a hydraulic ram and press assembly. The ram press is incorporated into the front vertical base of jack and provides a counter weight and also allows the press, engine stand and transmission cradle to be used simultaneously. The jack is equipped with caster wheels and the legs and boom are extendable to enable the jack to be placed in any necessary position.

Abstract: A lifting device comprises a fixed lower frame, an upper frame vertically movable with respect to the fixed frame and provided with members supporting the desired portions of the vehicle to be raised, articulated rods systems connecting the lower and upper frames, a mechanical energy generator placed between the articulated rods systems and acting on these so that to cause the raising of the movable frame with respect to the fixed frame, and a torsion bar connected to the fixed frame and acting on the movable frame in order to ensure its precise lifting.

Abstract: A load-handling apparatus usable for mounting missiles on an aircraft comprises a low wheeled support frame provided with braking and steering facilities, a pair of separate, side-by-side cranked support arms pivoted at one end on the support frame and hydraulically linked for synchronized vertical movement relative to the support frame about a horizontal axis, and load engaging structure at the other end of each support arm. Each cranked support arm is double cranked, so that, in a side elevation, it has a stretched, flat-bottomed V-configuration and the arms are movable about a common horizontal pivot axis on the support frame by an hydraulic actuator, whereby the hydraulic fluid serves to couple the support arms together for synchronized movements. The hydraulic actuator includes a master hydraulic cylinder connecting the support frame and one support arm and a sleeve hydraulic cylinder connecting the support frame and the other support arm.

Abstract: A pallet lift apparatus includes a substantially U-shaped enclosure having inner and outer walls and a lift cradle suspended inside the enclosure for supporting a wooden pallet or other loading platform. The cradle may be moved to a convenient vertical height by a hydraulic scissor lift for loading so that workers may stack the pallet without the bending and stooping that frequently causes low back pain.

Abstract: A motorcycle jack includes a frame having front and rear cross shafts rotatably supported thereon. Pairs of front and rear legs are secured to opposite ends of the respective front and rear cross shafts for rotation in unison with the shafts. A linkage mechanism interconnects the front and rear shafts for rotation in unison, but in opposite directions so that the frame is raised in response to pivotal movement of the front and rear legs toward one another and is lowered in response to pivotal movement of the front and rear legs away from one another. A power unit is provided for rotating their legs relative to the frame. The cross shafts are preferably formed of a resilient material so that the free left legs tend to spread slightly further apart than the interconnected right legs, thereby tilting the motorcycle slightly to the left for placement onto its kickstand when the jack is lowered.

Abstract: A wheeled hoist is illustrated having a base portion which may be readily disassembled for shipment having a tray forming a transverse frame for carrying a rearwardly inclined post or standard and a longitudinal base portion, all supported by wheels. The post carries a boom which may be mounted directly within the post to be raised and lowered, and the post is removably mounted to distribute an axial load to the base.

Abstract: A mechanism is described for mounting between two parts, such that the mutual distance between the parts may be varied. The mechanism includes a bar pivotally journalled in a bearing at one end and interconnected to an actuating device. The actuating device is pivotally suspended to one of the structures at one end and is connected to the bar at the other end. The pivot axis of the bearing extends obliquely to a plane containing the suspension point of the actuator and the point of connection between the actuator and the bar.

Abstract: A combination engine stand and engine puller crane is provided wherein the base frame of the engine puller crane removably interlocks with the base frame of the engine stand allowing one person to remove an engine from a motor vehicle by the use of the engine puller crane and then secure the engine to the engine stand.

Abstract: A track clearing device is described using hydraulic power for pushing apart rail vehicles which have been pushed into or onto each other. To provide such a track clearing device which may also be used successfully even where the anchorage resistance of the rails is very small and which enables derailed cars to be re-railed, an expander is provided comprising two pivotable expander arms, a pivot pin, two transverse guide pieces mounted so as to be displaceable by sliding and each having linked to it by articulated joints two lifter supports, two lifters and two displacement cylinders.

Abstract: A device for raising and lowering objects comprises a stand (1), an arm (5) pivotably supported on the stand for carrying a bed frame or the like, a power mechanism (8) for pivoting the arm (5) and a wedge (12) which is insertable between portions of the stand and arm in order to actuate these portions away from each other and thereby pivot the arm upwardly from the stand. The wedge (12) is movable perpendicularly to the pivot axis (6) of the arm (5) and is connected to a dog (18) adapted to abut a component (28) connected to the arm (5) after a certain initial introduction of the wedge between said portions (9, 10).

Abstract: An apparatus for driving fence post into the ground operable with a tractor having a power lift mechanism with two lift arms pivotally connected to the tractor for moving upwardly and downwardly in response to hydraulic force applied thereto, the apparatus including two lever arms pivotally connected to the chassis of the tractor, a rigid bar connecting the rear ends of the two lever arms, a pivot arm member rigidly connected to the rigid bar and extending upwardly therefrom, a base member rigidly mountable on the rear of the tractor chassis having a support arm member extending upwardly therefrom, and an elongated drive member pivotally connected to the upper end of the support member and to the pivot arm member for driving posts or stakes into the ground.

Abstract: A Compact Heavy Duty Lifting Crane (CHDLC) for removing and installing heavy objects such as engines and transmission from vehicles. The CHDLC incorporates a feature that allows the vertical lifting angle of the telescoping boom (40) to remain constant as the telescoping pylon cylinder (18) is raised. This feature is particularly useful for removing engines located in limited-space engine compartments such as those encountered in vans and buses. The CHDLC consists of two major assemblies: a base assembly and a portable lifting crane. When the CHDLC is used as a standard utility crane in a repair shop the crane is mounted to the base assembly. When the CHDLC is required to be mounted on a truck bed the crane is removed from the base assembly and installed on a truck pylon plate (14a) that is permanently mounted to the bed of the truck. Additionally, the CHDLC may be placed in its storage configuration. In this configuration the CHDLC occupies a horizontal area of only four square feet.

Abstract: A compactor particularly for junk vehicles, has a flatbed supporting a pair of opposed, hinged compaction doors. Each door has a linkage hydraulically operated to open and close the door for compaction of the vehicle against the flatbed. A winch disposed on the front of the compactor has its tow line extending beneath the doors and connects to the end of the vehicle opposite the flatbed to progressively advance the vehicle over the flatbed for compaction by the doors. A sequence control circuit is also provided which automatically opens and closes the compactor doors and automatically operates the winch to sequentially advance segments of the vehicle into the compactor. Additionally, the compactor can easily be made portable facilitating its transportation from one location to another.

Abstract: A conventional floor hoist having a removable attachment mounted thereon. The attachment comprises a swivel clamp which is removably mounted on the horizontally extending support arm of the floor hoist. A first frame member is pivotally connected at its upper end to the swivel clamp and extends downwardly therefrom. A second frame member extends forwardly from the lower end of the first frame member and has chains extending therefrom for attachment to the van engine. A length adjustable chain extends from the second frame member to the end of the support arm of the floor hoist to enable the attitude of the second frame member to be easily altered. The support arm of the floor hoist is pivotally movable by means of a hydraulic cylinder.

Abstract: An apparatus for laterally removing a workpiece, such as a guide roller on an endless track vehicle or motor from a piece of heavy equipment, from a space having limited vertical access. The apparatus includes a base for stably supporting the apparatus in a position laterally adjacent the workpiece, a support member secured to the base, a pivotable frame member pivotally secured to a portion of the support member, a cradle member for receiving and supporting the workpiece, which cradle member is secured to the pivotable frame member to be raised and lowered as the pivotable frame member is pivoted, and a force actuator, such as a hydraulic cylinder, supported by the support member and connected to the rigid pivotable frame member for pivoting it to raise and lower the cradle member as the force actuator is extended and retracted between its extended and stowed positions.

Abstract: A pipe straightening tool that includes an operating unit that can be inserted forwardly in a pipe as far as needed by use of detachable handle extensions. The unit includes an elongated lower segment and a parallel upper segment thereabove having a nose segment pivoted at its forward end for movement of the forward tapered end of the nose segment toward and away from the tapered forward end of the lower segment. The upper unit is movable toward and away from the lower segment on operation of a pair of connecting toggle linkages having a common actuator. A hydraulic cylinder unit is disposed between and connected to the actuator and another toggle linkage connecting the lower and nose segments so that extension of hydraulic cylinder unit concurrently urges upward movement of both the upper segment and the nose segment. All the segments present outwardly facing surfaces that are conformable to cylindrical surfaces. Boots can be attached to the segments to increase the effectiveness of the tool for larger pipe.

Abstract: A temporary roof support comprising a boom pivotally mounted and positioned on the front of the mining vehicle. A temporary roof support jack is pivotally mounted to the front of said boom. The jack comprises a base structure secured to the boom and extending laterally thereof. The base structure has four pivot pins including an inside pair of pivot pins symmetrically spaced on each side of the base structure and an outside pair of pivot pins symmetrically spaced on each side of the base structure. Two pairs of swing arms are pivoted to said inside pivot pins. Two linkage extensions are pivotally joined to each other and at opposite ends to the free ends of the swing arms. Two extensible hydraulic means are pivotally secured at one end to the outside pivot pins and pivoted at the opposite ends to the swing arms such that the axes of the swing arms and extensible hydraulic means are always crossed. A beam is attached to the pivot joint of the linkage arms for supporting the roof.

Abstract: A lift for raising mopeds and motorcycles, in which a base is provided to which there is hinged a jack, the rod of which is hinged to a frame rotating about a horizontal axis relative to said base; one end of the frame is provided with a motorcycle support adaptable to the footboard of a Vespa, on which it acts in the manner of a clamp, and adaptable to the stand of a normal motorcycle, which is wedged into it; if lifting a Vespa, the support is rotatable about an axis parallel to the axis of rotation of the frame, in order to incline the Vespa at two opposite angles about the vertical raised position.

Abstract: A vehicle lift having a platform mounted on a base for supporting a vehicle, and having a first link which moves the platform up and down. A table is mounted to the platform and supports the chassis of the vehicle by moving the table up and down by a second link. The table may be movably mounted to the platform and a safety device may be provided for preventing the platform from a sudden fall.

Abstract: A parallelogram arm assembly having a vertical arm for suspending a load at lower end thereof and a pair of horizontal arms one of which is guided in a horizontal path is provided. The other horizontal arm is guided in a vertical path. The paths are defined in a supporting structure which is mounted rotatably on a standard or the like. Apparatus, such as a piston/cylinder actuator is provided for maintaining in cooperation with the parallelogram a floating balanced state of the arm assembly independently of the loaded or no-load state.

Abstract: A jack assembly for side lifting of four wheel vehicles into tilted disposition is disclosed wherein elongated, rectilinear lifting arm means is provided which is of a length to extend substantially across the track dimension of the vehicle when the arm means is inserted under the vehicle from one side thereof. Extensible fluid actuated means is operably connected to the normally outboard end of the lifting arm means for swinging the arm means through an arcuate displacement to engage and lift one side of the car as the arm means pivots about the inboard end thereof which rests on the ground. The jack is especially useful for raising one side of smaller unibody automobiles without damage to the body or operating components.

Abstract: A compact hoisting device is constructed with a primary hoist link pivoted at one end on a shaft secured to a base and pivotally connected to a final hoist link by means of a journal in the other end. A load support is pivotably mounted at the free end of the final hoist link on a shaft driven by attitude control transmission means into a constant spatial attitude regardless of the angular movement of the primary and final hoist links. Motion transmission means engage said journal to ensure that the angular rotation of the final hoist link mirrors the rotational motion of the primary hoist link, itself governed by a hydraulic jack or other drive means. The motion transmission means and the attitude control means may employ planetary gear trains, sprocket-and-chain drives, or parallel-rod drives, as suited to a particular application. One or more intermediate links may be interposed between the primary and final hoist links, with the several links in the hoist train sequentially pivoted to one another.

Abstract: A plow caddy for facilitating attachment of a plow, such as a snowplow, having a blade and a connecting frame provided with a rear connecting portion to a vehicle having an elevated attachment portion. The caddy includes a wheeled support having front and rear portions. In the illustrated embodiment, a channel is provided on the front portion for removably receiving the lower edge of the plow blade for supporting the plow blade during positioning movement of the caddy. A manually operable adjusting device is provided on the support for adjustably elevating a rear supporting element on the wheeled support for correspondingly elevating the rear connecting portion of the plow frame to align it with the vehicle attachment portion. The adjusting device includes a handle which is manipulatable at the front of the caddy for facilitating the controlled elevation of the plow frame rear portion.

Abstract: A portable hydraulically operated rescue tool has a pair of force arms supported for pivotal movement adjacent inner ends and an hydraulic piston-cylinder assembly for pivoting the arms to move the outer end portions of the arms generally toward and away from each other between adjacent and spread apart positions. Spreader plate assemblies are releasably connected to the outer ends of the force arms. Each plate assembly includes a spreader plate connected to an associated force arm to pivot about an axis which extends transversely of the longitudinal axis of the arm and which is spaced longitudinally inwardly from the outer end of the arm. Each plate may be further supported to swivel about a central axis normal to its pivotal axis. One of the plates may have an arcuately concave contour for gripping engagement with a cylindrical member, such as the steering column of a motor vehicle.

Abstract: A device for lifting an implement carried by an agricultural tractor three-point linkage has a flexible bar connected at its ends to the said lower linkage arms for rotation about a transverse axis, the reaction forces transmitted from the ground to the implement, when the latter is lowered into the ground, causing flexural deformation of the bar in a horizontal plane to effect operation of a distributor control shaft through a linkage which includes a first lever fixed at one end to the center of the bar, and acting through an inclined slot and pin on a second lever so that the weight of the implement when lifted from the ground causes the linkage arms to rotate about their connections to the respective tie-rods, deforming the flexible bar in a vertical plane and causing rotation of the distributor control shaft in a sense to return the implement rapidly to the ground.

Abstract: A boom arm of a boom assembly is formed of a pair of side walls integrated into a box boom structure where the top and bottom plates are roll formed with transition edges providing a weld bed for welds attaching the side walls to the top and bottom plates. The particular cross sections of the top and bottom plates provide a weld blow-through preventing barrier and also dimensional guidance and tolerance control during assembly of the boom arm.

Abstract: An adapter for a jack is used in front end alignments to jack up a vehicle in a safe position. The adapter includes a generally horizontally extending elongated rocker arm, with a jack attachment member pivotally secured near the center of the rocker arm. The jack attachment member extends downwardly from the underside of the rocker arm for attachment to the ram of a jack placed on a wheel alignment rack below the front steering control arm of the vehicle. The rocker arm extends laterally away from both sides of the ram. An inner end of the rocker arm is attached to the generally horizontal underside of the steering control arm immediately inside the wheel of the vehicle. This provides a safe location at which to jack up the vehicle. The outer end of the rocker arm is pivotally attached to the top of an elongated upright support arm. A rack attachment member fastens the bottom of the support arm to the wheel alignment rack.

Abstract: An improved post puller includes a U-shaped grapple and a pivot mount providing both a generally vertical pivot position for connection of the grapple to a draw bar and a base for mounting an operating handle thereto. One alternate embodiment provides adjustability. Further, the handle and pivot axis are specifically disposed in varying alternate positions for first rotating the grapple to grasp a post and then to permit rotation about another axis for post pulling. Another alternate embodiment includes a double grapple and actuating apparatus for opening and closing it about a post.

Abstract: A method and apparatus for use in breaking wood, such as wood splitting and tree felling, for causing the wood to break under the influence of a force acting on the cutting surfaces of a notch in the wood, such as a saw notch. The wood breaking force is produced by means of an inflatable cushion which is inserted in a flattened state into the saw notch and connected to the combustion chamber of the cylinder of the power saw motor to be inflated with compressed gas from the combustion chamber. Also disclosed is a special spark plug for the power saw motor for use in supplying the compressed gas from a combustion chamber to the inflatable cushion.

Abstract: A jack is provided that is adapted to be used for lifting and handling heavy objects or loads such as vehicle engines, heads, manifolds, air conditioners and the like. The jack includes a means for permitting the device to be motor operated or manually operated. The jack is mounted on swivel wheels and the jack can be maneuvered in various directions.

Abstract: A hydraulic cylinder and piston mechanism which acts on opposing levers with a fulcrum bar interposed to prestress a shear lever bolt of a gate restraining mechanism of a hydraulic turbine without reacting on any other component.

Abstract: A manhole cover lifter that is formed by a single arm lever structure with a pair of adjustable lifting jaws that penetrate and attach to a manhole cover to remove and relocate it. The arm also contains adjustable hooks that are for other cover configurations. The invention is stabilized by three retractable legs allowing the lifting arm to rotate horizontally. The lifting power of the arm is provided by an integral hydraulic jack or in other embodiments a hydraulic or pneumatic cylinder or a hand operated cable reel. A wire rope embracing a pulley attached to the vertical column provides a connection between the jack and the arm. This pulley is raised by the jack, or actuating means, subsequently elevating the arm into a vertical position where it is then rotated allowing the cover to be deposited radially away from the manhole.

Abstract: A lift system for a wheelchair or the like on a transit vehicle includes a stationary main frame secured within a doorway recess of the vehicle and a side frame that is movable relative to the main frame. An articulated platform including first and second steps is pivotally secured to the side frame. Scissors linkage is pivotally and slideably connected to the main frame and to the platform such that upon being actuated, the platform may be actuated from a first position defining first and second steps to a second position defining an extended platform. Thereafter the platform may be actuated in a manner such that the scissors linkage crosses over its center point to lower the platform from the floor level of the vehicle to the ground level. Once the wheelchair or the like is mounted on the platform the reverse actuation occurs and the scissors linkage again crosses over its center point to raise the platform from the ground level to the floor level.

Abstract: A scissor hoist attachment for pickup truck beds to convert a fixed bed truck with a passenger cab and hauling bed supported on a frame to a tilting bed truck. The hoist upon installation allows the truck bed to be rotated from a horizontal to a tilt position so that the truck cab and bed are in the same relative relationship in the horizontal position as before the installation of the hoist, i.e. the hoist does not alter the original body lines of the truck. The hoist is a four bar linkage. The yoke utilizes one cylinder to operate a scissors of wide pivotal area but narrow at its mountings. The wide pivotal area permits use of the space around the truck differential since the scissors side plates and spreader plate straddle the truck differential and permit a heavier payload to be lifted. The wide pivotal area enables the hoist to be used with essentially all standard pickup trucks and makes the hoist effectively universal.

Abstract: A tool for insertion into a core including a pair of pivotally connected levers having forwardly-extending jaws for insertion into the core and rearwardly-extending actuating portions to which the opposite ends of a flexible-wall fluid actuator are fixed for applying force to the actuating arms and pivotally expanding the jaws.

Abstract: An engine hoist with a hydraulically powered lifting boom is attached to and used in combination with an automobile hoist.

Abstract: A leverage device for use with various jacking means may be folded to occupy a minimum of space during storage but can be unfolded and set in an operative condition to be made fully functional to cooperate with various conventional jacking devices, the device providing a scissoring action for raising and lowering an object when the jack is actuated.

Abstract: A convertible boom is supported by an upstanding post and base frame. The boom is provided with appropriately located connectors so that it may be attached to the upper portion of the post to form a hoist or it may be connected proximate the bottom of the post to create a jacking device. In both cases, a portable jack is used to actuate the boom. The end of the boom may be equipped with a rotatable and tiltable cradle having extendable arms. The upstanding post may be provided with a rotatable workpiece mount which includes a plate having a plurality of outwardly projecting pins which extend through slotted connector rods. The rods can be arranged in a variety of positions to facilitate connection to a workpiece.

Abstract: A lift mechanism comprising a base, a lift arm pivoted to the base and a platform pivoted to the lifting arm includes a locking device operating between the lift arm and the platform to releasably lock these two components together if the platform deviates from a horizontal position thereby presenting further movement of the platform from the horizontal.

Abstract: An hydraulic log splitter in the form of an implement securable to the three-point hitch at the rear of a vehicle or tractor and in which is distinctively adapted to remain attached to the vehicle without hindering normal towing function thereof, which uses the leverage benefit of a lever arm between the hydraulic cylinder and the splitting wedge, which may be operated by a single person, and is adjustable in relation to the length of logs to be splitted. This log splitter implement comprises an upstanding portion, teeth upwardly spaced apart along the upstanding portion, a lower portion adjustably resting on one of these teeth, a lever arm pivoted to the upper end of the upstanding portion, a splitting wedge fixed to the lever arm and overlying the lower portion, an hydraulic cylinder and a valve operating the lever arm to split a log resting upright on this lower portion.

Abstract: Repositionable lift apparatus is constructed of a boom pivoted at one end near the upper end of a post. The other end of the boom pivotally supports a platform and a power cylinder is provided to pivot the boom to raise its other end from a loading position to a working position. In the loading position of the boom one end of the platform is a grade so that a vehicle may be rolled thereon. In the working position of the boom a stop means on the platform engages the boom to position the platform in a raised generally horizontal position. A manually operated winch is provided on the boom to load a vehicle on to the platform and a safety means automatically positions itself to block sudden collapse of the power cylinder arm.

Abstract: A lifting platform which is supported from a base by a pair of X-linkages which are of the kind in which the foot of a first arm of the X is pivoted to the base, the foot of the second arm of the X slides on the base and the head of the second arm is pivoted to the platform. The invention is characterized by the head of the first arm being connected through a swinging link to the platform so the platform moves parallel to itself while being lifted.