US4158524A — Mobile chair lift

Claim 1

Independent Claim 249 words

A chair lift comprising a base frame, a platform, longitudinally-spaced pairs of transversely-spaced legs pivotally connected at their lower ends to the base frame and at their upper ends to the platform so as to enable raising and lowering the platform relative to the base frame for maintaining it in parallel relation thereto, means for raising and lowering the platform comprising transversely-arranged spools, cable means connected at one end to the spools and at the other end to the platform, a gear reducer to which the adjacent ends of the spools are connected, a motor connected to the gear reducer for effecting through the gear reducer rotation of the spools in directions to on the one hand wind the cable means onto the spools and on the other hand to unwind the cable means from the spools, a first idler roll over which the cable means passes from the spools to the platform, a second idler roll situated forwardly of the first idler roll and at a level above the base with which the cable means is brought into engagement as the platform is lowered toward ground level so that at ground level the cable means travels downwardly from the first idler roll over the second idler roll at an angle of approximately 30°, said platform when lowered to the level of the base frame extending forwardly from the base frame and providing a surface onto which a wheelchair may be wheeled which is closely adjacent the ground level.

Claim 2

Dependent Claim 249 words

A chair lift comprising a base frame, a platform, longitudinally-spaced pairs of transversely-spaced legs pivotally connected at their lower ends to the base frame and at their upper ends to the platform so as to enable raising and lowering the platform relative to the base frame for maintaining it in parallel relation thereto, means for raising and lowering the platform comprising transversely-arranged spools, cable means connected at one end to the spools and at the other end to the platform, a gear reducer to which the adjacent ends of the spools are connected, a motor connected to the gear reducer for effecting through the gear reducer rotation of the spools in directions to on the one hand wind the cable means onto the spools and on the other hand to unwind the cable means from the spools, a first idler roll over which the cable means passes from the spools to the platform, a second idler roll situated forwardly of the first idler roll and at a level above the base with which the cable means is brought into engagement as the platform is lowered toward ground level so that at ground level the cable means travels downwardly from the first idler roll over the second idler roll at an angle of approximately 30°, said platform when lowered to the level of the base frame extending forwardly from the base frame and providing a surface onto which a wheelchair may be wheeled which is closely adjacent the ground level.

Claim 3

Dependent Claim 211 words

A chair lift comprising a rigid base frame, longitudinally-extendible legs, one at each of the four corners of the base frame, means pivotally connecting the lower ends of the legs to the four corners of the base frame, a platform, means pivotally connecting the upper ends of the legs to the four corners of the platform, said platform being movable by pivotal movement of the legs from a position at the level of the base frame to an elevated position above and parallel to the base frame, a capstan on the base frame, cable means connected at one end to the capstan for winding on and unwinding from the capstan and at the other end to the platform, a first idler roll supported above the capstan over which the cable means is entrained, means for effecting rotation of the capstan and a second idler roll arranged forwardly of the first idler roll on an axis parallel thereto and at a lower level in a position to intercept the cable means as the platform moves toward the level of the base to dispose the cable means running from the second idler roll to the platform at a steeper angle than that running from the second idler roll to the first idler roll.

Claim 4

Dependent Claim 211 words

A chair lift comprising a rigid base frame, longitudinally-extendible legs, one at each of the four corners of the base frame, means pivotally connecting the lower ends of the legs to the four corners of the base frame, a platform, means pivotally connecting the upper ends of the legs to the four corners of the platform, said platform being movable by pivotal movement of the legs from a position at the level of the base frame to an elevated position above and parallel to the base frame, a capstan on the base frame, cable means connected at one end to the capstan for winding on and unwinding from the capstan and at the other end to the platform, a first idler roll supported above the capstan over which the cable means is entrained, means for effecting rotation of the capstan and a second idler roll arranged forwardly of the first idler roll on an axis parallel thereto and at a lower level in a position to intercept the cable means as the platform moves toward the level of the base to dispose the cable means running from the second idler roll to the platform at a steeper angle than that running from the second idler roll to the first idler roll.

Claim 5

Dependent Claim 50 words

A chair lift according to claim 2 wherein the means for effecting rotation of the capstan is a motor and there is an electric circuit and a switch mounted on the platform in a position to be operated by the occupant of the wheelchair to effect operation of said motor.

Claim 6

Dependent Claim 30 words

A chair lift according to claim 2 wherein the legs comprise axially aligned parts, one of which is threaded into the other to enable changing the length of the legs.

Claim 7

Dependent Claim 21 words

A chair lift according to claim 2 wherein there is a downwardly-inclined ramp along the entire forward edge of the platform.

Claim 8

Dependent Claim 27 words

A chair lift according to claim 2 wherein there are wheel stops on the base frame for determining the position of a wheelchair rolled onto said platform.

Claim 9

Dependent Claim 24 words

A chair lift according to claim 6 wherein said wheel stops on the base frame are longitudinally adjustable for accommodating chairs of different size.

Claim 10

Dependent Claim 23 words

A chair lift according to claim 2 wherein there is means for limiting rearward movement of the platform rearwardly from its elevated position.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1982-06-18	1982-12-18	1983-06-19	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1986-06-18	1986-12-18	1987-06-19	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1990-06-18	1990-12-18	1991-06-19	$7700.00	Window Closed / Lapsed

Mobile chair lift

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