GB693983A - Improved invalid chair or the like - Google Patents

Abstract

693,983. Endless-track vehicles. JOHANNESEN, H. A. J. Oct. 11, 1950 [Oct. 11, 1949], No. 24816/50. Class 79 (i) An invalid chair comprises an endless band or pair of bands 13 in an inclined position relative to the normal plane of movement of the chair, the rear wheel or wheels 15 being mounted on a movable bracket so that they can be moved to a position above the plane of the bands. As shown, each band comprises an endless belt of V or other cross-section, on each side of the chair, and is mounted on upper and lower pulleys 11, 12. A bracket 16 carrying a pair of wheels 15 is pivotally mounted at 17 and is rigid with a sector ring, or (as shown) a disc 22. Notches 21, 23, 24 in the disc co-operate with a spring-pressed latch 19 which is releasable by movement of a lever 26 on the handle 2 of the chair acting through a cable 25. The disc 22 is connected at 17 with a spring unit 29, the connections to which are arranged so that the wheel 15 is urged to its lower position (full lines in Fig. 2). Upward movement of the wheels 15 may be cushioned by the action of air within the unit 29, and a rubber cushion 33. An electric or i/c driving motor 38 may act through gearing 39, 40, and a differential gear (not shown), on the axle 10. A brake block 34 is urged by a spring 35 into engagement with one of the upper belt pulleys 12. In order to release the brake, it is necessary to depress a lever 37 on the handle 2. A respective brake and associated control lever may be provided for each wheel 12 so that in conjunction with the differential gear in the drive of the motor 38, the chair may be steerable by its occupant. Front wheels 9 may be replaced by a single wheel or may be dispensed with, the chair then resting on the pulleys 11. The axle of the pulleys 12 may be laterally adjustable in order to adjust the inclination of the belt 13. Instead of being movable circumferentially into position, the mounting of the wheels 15 may be arranged to move the wheel longitudinally. The spring unit 29 may be replaced by a counterweight mechanism. The two belts 13 may be replaced by a single broad belt disposed centrally of the chair. The chair may be adapted for carrying furniture, &c. In operation, on commencing to mount stairs, the chair is pulled backwards until the wheels 15 engage the first stair. The latch 19 is then released, so as to permit the wheels 15 to be pushed by contact with the stairs into the position shown dotted at 15<SP>1</SP> in Fig. 2. In descending, the stairs are permitted to deflect the wheels 15 into the position 15<SP>11</SP>. The wheels 15 may be replaced by a single wheel mounted on a slewing bracket.