GB339694A - Improvements in and relating to variable transmission gears - Google Patents

Abstract

339,694. Thomson, B. Sept. 21, 1929. Variable-speed gearing comprises two or more sliding elements which are moved in groups for some speeds and singly for others, at least one such element comprising a claw clutch member prevented from engaging while its speed is asynchronous. Thus a sleeve 13, Fig. 1, with a toothed gear 21 has dog clutch ends 12, 22 coacting with friction members 15, 27, respectively, which prevent asynchronous engagement as described in Specification 332,302. The sleeve 13 splined on driven shaft 8 and a sleeve 37 splined on lay shaft 34 are moved simultaneously to left and right of Fig. 1 to engage a clutch 11 on driving-shaft 5 directly, for high speed, and to engage a clutch 25 on a loose gear 26, for middle speed, respectively. For low speed, the sleeve 37 is moved independently to the left to engage pinion 38 with gear 21, and, to effect reversal, the sleeve 37 is moved to the right to entrain an idler 40. A control lever 46 is adapted to engage either two selectors simultaneously, or one selector only, the other being locked. A four-speed form is described having an additional synchronized clutch and a reversing idler brought in by eccentric movement in its own plane. A modified form of synchronized clutch is shown in Figs. 11 and 12. Dog members 154, which pass through shaped apertures in the synchronizing friction members 153, carry the actual clutch claws 156 in groups. The claws 156, which have sharpened ends, engage similar internal claws 149.