Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
218 words
An electric drive attachment for a wheelchair comprising: wheelchair comprising: an electric motor constituting the input member of said drive, a wheel adapted to touch the ground by force of gravity only and to drive said wheelchair by frictional contact with said ground, said wheel constituting the output member of said drive, wherein said input member and said output member constitute an integral unit carried by a sleeve-like member slidably mounted on a carrier arm releasably attachable to a mounting member articulatedly affixable to said wheelchair and downwardly tiltable by gravity, first means being provided to allow said unit to be manually shifted to, and arrested at, at least a first predetermined power-drive position and a second predetermined power-drive position along said carrier arm, in the first of which positions said unit is closer to a reference point on said wheelchair and in the second of which positions said unit is more remote from said reference point, wherein in said first power-drive position, said carrier member includes with said ground a first angle, and in said second power-drive position, said carrier member includes with said ground a second angle, said first angle being the angle at which the ground grip of the ground-touching wheel assumes an optimal value and said second angle being smaller than said first angle.
Claim 2
Dependent Claim
218 words
An electric drive attachment for a wheelchair comprising: wheelchair comprising: an electric motor constituting the input member of said drive, a wheel adapted to touch the ground by force of gravity only and to drive said wheelchair by frictional contact with said ground, said wheel constituting the output member of said drive, wherein said input member and said output member constitute an integral unit carried by a sleeve-like member slidably mounted on a carrier arm releasably attachable to a mounting member articulatedly affixable to said wheelchair and downwardly tiltable by gravity, first means being provided to allow said unit to be manually shifted to, and arrested at, at least a first predetermined power-drive position and a second predetermined power-drive position along said carrier arm, in the first of which positions said unit is closer to a reference point on said wheelchair and in the second of which positions said unit is more remote from said reference point, wherein in said first power-drive position, said carrier member includes with said ground a first angle, and in said second power-drive position, said carrier member includes with said ground a second angle, said first angle being the angle at which the ground grip of the ground-touching wheel assumes an optimal value and said second angle being smaller than said first angle.
Claim 3
Dependent Claim
126 words
The drive attachment as claimed in claim 1, wherein said mounting member is substantially in the form of a V, the two limbs of which have the shape of two arms, the first ends of which are hingedly articulated to a head piece in such a way as to render said arms collapsible from a first position in which the angle included by said two arms is at a maximum, to a second position in which said angle approximates zero, and the second ends of which arms are hingedly articulated to first members of brackets means attachable to members of said wheelchair, whereby said mounting member is adapted to tilt about an axis substantially parallel to the common axis of the rear wheels of said wheelchair.
Claim 4
Dependent Claim
50 words
The drive attachment as claimed in claim 2, wherein said first member of at least one of said bracket means is a locking means adapted to co-act with latch means to arrest said mounting member in a position of tilt in which said output member is lifted off said ground.
Claim 5
Dependent Claim
30 words
The drive attachment as claimed in claim 1, further comprising cable means to release said mounting member from the position in which said output member is lifted off said ground.
Claim 6
Dependent Claim
65 words
The drive attachment as claimed in claim 1, wherein said first means is constituted by a manually operable detent fixedly mounted on said sleeve-like member and comprising a spring-loaded plunger adapted to selectively drop into either one of at least two bores provided in said first portion of said mounting member and thereby arresting said unit in either one of said at least two positions.
Claim 7
Dependent Claim
45 words
The drive attachment as claimed in claim 1, further comprising microswitch means to cut off power to said input member when the steepness of tilt about an axis substantially parallel to the common axis of the rear wheels of said wheelchair exceeds a pre-determinable limit.
Claim 8
Dependent Claim
104 words
The drive attachment as claimed in claim 1, further comprising a safety roller mounted on an arm attached to said unit in such a spatial relationship with said drive wheel that when, due to an obstacle in the path of said wheelchair, the acute angle included between the ground and a plane passing through an axis of tilt of said mounting members on the one hand and through the point of tangency of said wheel with said ground on the other, exceeds a predetermined limit, said roller, being thereby pressed against the ground, will cause said wheel to lose drive contact with the ground.
Claim 9
Dependent Claim
36 words
The drive attachment as claimed in claim 1, further comprising means to adjust the angular relationship between the vertical central plane of said drive wheel and the vertical plane containing the longitudinal axis of said wheelchair.