Abstract: To reduce the weight of the collapsible wheelchair, and the depth of the wheelchair, when collapsed, only three spreader braces (25,49,51) are used to connect, respectively, the back and side frame elements, (45,47) of the collapsible wheelchair together, the remaining interconnection being formed by tension cables (53;57',57",59"), which tend to counteract the spreading effect of the collapsible spreader braces, and are located, with respect to the spreader braces, in triangular position, one (53) of the tensioning cable extending parallel to two spreader braces (49,51) located in triangular configuration with respect to the frame elements (45,47), and other tensioning cables extending diagonally, in pairs (57,59) between the frame elements (45,47), located at the rear portion of the chair to hold the rear portion towards each other when the weight (24) of the user tends to pull together the forward portions (45d,47d) of the frame elements (45,47).

Abstract: The raising wheel chair substantially comprises the frame (11), wheels (13 and 15) and the seat (17) pivotably connected to the frame (11). A footrest (21) at the front and a backrest (19) at the back are pivotably connected to the seat (17). For raising the user into an upright position, a spring (27) applies a force which acts counter to the weight of the user, so as to facilitate raising the user to an erect position. A support arm (37) which can be arrested in various positions is pivotably connected to the pivot axis on both sides of the frame (11). To arrest the support arm, the locking lever (41) has a multiplicity of locking positions (45), which can be engaged by a locking element (47). The arm (37) can be put into a horizontal position, in which it offers no hindrance to the user in performing a lateral transfer movement, for instance to shift to a toilet seat.

Abstract: A main frame (11), supporting main wheels (25) at different wheel positions, is coupled to a seat erection frame (13) by a parallogram linkage. To permit matching of the erecting chair to different-size persons, for example so that it can "grow" with growth of a child for whom it is initially purchased, the parallelogram linkage (45) connecting the back (35) to the frame (13) can be provided in interchangeable sets of different-length links (45a, 45b) to respectively move the back (35) in different positions with respect to the front edge (34a) of the seat, the ground support (37) likewise being adjustable to accommodate differently tall patients, adjustment of the seat with respect to ground level being additionally obtained by adjusting the height of front caster wheels (27) with respect to the main frame. The position of the main wheels (25) can be relocated with respect to the center of the seat (33) by different pivot locations on the main frame.

Abstract: To provide for smooth simple operation of an erecting seat, a motor, through a reduction gearing, drives a shaft located transverse of the seat structure, or wheelchair, to the end points of which a crank drive is attached coupled to the seat, the crank drive being arranged to provide, upon erecting or lowering movement of the seat a nonlinear time-displacement function which is effectively sinusoidal, so that movement of the seat between the end positions starts slowly, then is accelerated, and then again slowly reaches the end position. Erecting movement can be assisted by springs, preferably located at either side of the seat.