GB1512779A - Stair lifts - Google Patents

Abstract

1512779 Elevators associated with stairs H CHAPMAN 20 Jan 1976 [21 Dec 1974] 55334/74 Heading B8L An elevator associated with a staircase 6 comprises parallel rails 2 mounted on the stairs and presenting outwardly facing grooves 18 along which a pivotable invalid chair 8, 11 is guided and inwardly facing grooves 20 along which a counterbalance load carrier 10 is guided, the chair and carrier being interconnected by a plurality of cables 24 which pass around pulleys 26 at the upper end of the rails 2 so that the chair and carrier reach opposite ends of the rails simultaneously. The frame 11 for the chair 8 and the carrier 10 have guide wheels 16 shaped to engage the rail grooves which have a V- sectioned lower surface. The rails 2 are supported on each stair tread through either angle pieces 4 or flat plates secured to the rails and anchored to the stair tread. The chair and/or the load carrier 10 incorporate a spring loaded catch for automatic engagement with and manual release from recesses at the upper and lower ends of the rails. In operation, the carrier 10 is loaded with weights 40 to make it substantially equal in weight to the chair plus its intended occupant whereby upon release of the catches, a small force applied to the chair will propel it up or down the rails. The chair frame 11 includes a foot rest 42. In the embodiment of Fig. 3 (not shown) the locking means for the chair frame and/or load carrier comprises a key operated mortise lock on either the rail or moving body, engageable with an aperture on the moving body or rail respectively.