Self-propelled invalid chair

摘要

The wheelchair, (30) has a main body (31), a drive motor (32) three revolving bases (38,39) and several running balls (1) on ball bearings. The drive motor is built into the main body. The revolving bases are driven by the motor via drive axles (38a,39a). The running balls have a braking device. They are fitted to each of the revolving bases, so that the bases run via them on the floor surface. The running balls may be able to move relative to the floor surface in the same plane, in which case they consists of one large ball running on the floor and several small balls running on the upper part of the large one.