Schakelinrichting voor een gangwissel

摘要

878,078. Change-speed control. ZAVODY 9. KVETNA, NARODNI PODNIK. Jan. 21, 1959 [May 26, 1958], No. 2257/59. Class 80 (2). In a preselective control mechanism for change-speed gearing for single track and other small motor vehicles, a profile member or members 1 which is or are mounted on a shaft 4 arranged transversely of shift fork guide rail or rails 17 and each of which comprises cam slots formed in the wall of a complete or sectoral cylinder or multi-sided prism, is or are rotated for ratio preselection, and axially displaced for gear establishment, the cam slots acting directly on pegs 13 of forks 15. One profile member 1 may actuate several forks as shown, or several members 1 may each actuate one fork. The preselecting and/or gear establishing movement of the member(s) 1 may be effected electromagnetically. In Figs. 1, 2 a single pentagonal member 1, the sides of which have formed therein pairs of cam slots giving N, 1, 2, 3, 4, is splined on a shaft 4 which is rotated by a preselecting means (not shown) through a cable or chain 9 and a pulley 8 fast on the shaft 4 and positioned by a detent 22. The member 1 is axially displaced for gear establishment, against a spring 7, by a lever 11 actuated, against a spring 24, by a pedal executive lever 12. Rotation of the member 1 during the establishing action is prevented by engagement of the lever 11 in one of slots 23 in the member 1. The forks 15 on the single guide rail 17 each have three positions which are maintained after the establishing action, when the member 1 and the lever 11 are respectively returned by springs 7, 24, by detents 21 engaging rail notches 18, 19, 20. The cam slots are so shaped that one of the forks is first shifted into neutral in advance of a gear establishing shift of the other fork. In Fig. 4 (not shown) two spaced members 1 together splined on the shaft 11 have single cam slots formed in each of their five sides to coact with pegs of two forks 15 on individual rails The member or members 1 may be fast on an axially slidable shaft 4 splined in an axially fixed disc 8 (Fig. 6, not shown) the rotation of the member or members 1 during the establishing action being prevented by a key on the shaft 4 which, during the said action, engages one of five splines in a fixed bearing. A cam such as an eccentric disc may replace the lever 11. The member(s) 1 may comprise cam slots for several gear speeds, including reverse.