Abstract: An office chair includes a base and a height adjustable seat mounted to the base and having a front end. The base includes a pair of centrally positioned, laterally spaced apart drive wheels that are manually operated by a user or which are motorized.

Abstract: Wheelchair of which a sitting support is pivotable about a virtual or non-virtual pivot axis, extending substantially horizontally, substantially at right angles to a main driving direction of the wheelchair, wherein the upper part of the body of the user, at least its center of gravity, viewed in the main driving direction, lies behind the pivot axis and wherein the pivot axis is located preferably adjacent the hinge point of the knees of a user seated in the wheelchair during use. The sitting support may be freely pivotable about said pivot axis or be fixed at a particular pivot angle. The pivot axis can for instance be designed as a torsion bar.

Abstract: Assembly of at least two wheelchairs, each provided with at least three wheels, a frame and a sitting support, wherein the wheelchairs are nestable, in such a manner that the wheelchairs in a nested condition occupy considerably less space than in unnested condition, while the wheelchairs upon being unnested are substantially directly ready for use, and an assembly wherein two wheelchairs in the assembly in nested condition occupy a floor area, preferably a floor area which is at most 90%, preferably less than 75% and in particular less than 60% of the floor surface occupied by the same two wheelchairs in unnested condition.

Abstract: The apparatus is a biomechanical body support including a substructure, a seat which is supported by said substructure and is tiltable relative to said substructure, a backrest which is coupled to said seat and is tiltable relative to said seat, the tilting axis of the backrest approximately coinciding with the pivotal point of the hip joint of a person resting on said seat, as well as a leg support also tiltably connected to said seat.

Abstract: A driving gear for a muscle power driven vehicle, such as a wheel chair, comprising an input shaft drivable by means of a lever, and adapted to be coupled through at least two freewheel clutches to an output shaft arranged to be connected to a wheel hub of the vehicle, wherein the driving gear (4) is housed in a closed housing (11, 12) which is arranged to be coupled through said output shaft (22) to the wheel hub (5) of the vehicle, said input shaft (7) being fixedly coupled to an input gear wheel (14) meshing with two separate intermediate gear wheels (16, 16') adapted to be connected through freewheel clutches operative in opposite directions of rotation to one (20) or the other (20') of two meshing change gear wheels, one of which also meshes with a first output gear wheel (21) mounted on the output shaft.