To assist a person from seated to an erect position a mechanism for raising and straightening a seat surface and the seat backrest to a nearly vertical position is provided, which avoids substantial relative motion between the body of the person and the seat surface and the seat backrest. In the erected position of the chair, a groundplate of the footrest is firmly supported on the ground.

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.

A wheelchair including motor-operated means for raising and lowering a partially paralyzed person from a seated to a substantially standing position. The same motor also provides propelling means for the wheelchair while in both its lower and raised position. The seat, arms, back and front braces form a parallelogram which is pivotable about its axes to form a back support when raised to the standing position. Suitable means are provided for restraining the patient in the chair when in the standing position to provide support, both while standing and moving around in the upright position.

A patient chair is provided that includes a chassis with a frame, a seating device intended for a patient and connected to the chassis, and a driving device for moving the seating device relative to the frame in the vertical direction between a lower position and an upper position, wherein in the upper position the seating device and, thus, a patient sitting in it are inclined backwards relative to the lower position. In one implementation, a stand belonging to the chassis extends upwards from the frame, and an element connected to the stand is continuously arched. Means cooperating with each other and positioned on the stand and the seating device are arranged for guiding the seating device along the element in the movement of the seating device between the lower and upper positions, so that the seating device is continuously gradually tilted in the course of its curved movement in the vertical direction.

A flexible back support for use in seats such as automobile seats or office chairs, includes a central body portion with outwardly extending support fingers such that an arch having a variable apex is formed when the back support is subtended longitudinally. The longitudinal location of an apex and the shape of the arch formed on the back support changes responsively to a load imposed by a person's back. Noise, galling, wear and rough movement between moving parts of the flexible back support are reduced by the coefficient of friction reduction method of the present invention.