| 摘要 |
1436134 Adjustable backrests H R TURNER (WILLENHALL) Ltd 15 Aug 1974 [22 Aug 1973] 39721/73 Heading A4J [Alsoin Division E2] A vehicle seat has a backrest which is adjustable in one direction against a biasing force but which may be moved beyond a predetermined position in the opposite direction without operation of the biasing force. The biasing force may be provided by a scroll spring 32, Fig. 3, one end 33 of which is engaged in a slot at the end of a tube 13 and the other end 34 of which engages an abutment 35 on a bracket 14b. The tube 13 is fast with a plate 15b which in turn is fast with the backrest, while the plate 14b is fast with the seat frame and is apertured to pivotably mount the tube 13. The spring thus acts to rotate the backrest anti-clockwise with respect to the seat frame until:- (a) the spring is relaxed whereupon the end 34 leaves abutment 35 (b) an abutment 36 on plate 15b engages end 34 while the spring is still stressed to carry it out of engagement with abutment 35. In either case the seat back is free to pivot forwardly (i.e. for admission of rear seat passengers). The seat back may be locked in a desired "in use" position by the mechanism of Fig. 2, which is preferably on the opposite side of the seat from the scroll spring. A toothed track 19 affixed to the seat bracket 14a is engageable by a pawl 17 rotatable on tube 13. An abutment 29 on the pawl engages a surface 28 on plate 15a to lock them with respect to clockwise rotation of the backrest, while clockwise rotation of the backrest with respect to pawl 17 is allowed after release of a catch 26. The setting of the pawl 17 with respect to track 19 may be altered by bodily raising the seatback until pawl 17 and track 19 disengage. To this end the aperture in plate 14a which receives tube 13 is elongate and a cam 20 engages a cam follower 23 on the tube to perform the displacement. |
