GB254848A - Improvements in and relating to change-speed gear control - Google Patents

Abstract

254,848. Alltree, A. May 15, 1925. Controlling variable-speed gearing. -The control comprises two coaxially arranged cam members r, t, Fig. 3, mounted parallel with gear shafts such as a, d, each cam being turned independently and being formed to actuate a fork or yoke such as m, n to effect two gear changes. Pins o, o<1>, Fig. 6, may be on the separate turning members r, t, the cam grooves being on the forks m, n. The gearing is of the type in which two members &c. u, w<1> are moved each to both sides of neutral into gear positions, thus yielding four speeds. Thus in the arrangement shown in Fig. 1, there is a driving- shaft a, is driven sleeve d, a lay shaft h, and two medial pairs of clutchended meshing gears e. k and f, i severally coupled and controlled by the yokes m, n. The cam t, Fig. 4, is preferably connected through a spindle t<2> to a crank arm q<1> and the cam r through a sleeve r<2> to a like arm q, so that the required control is effected by moving the arms q, q<1>. To effect that only one can be moved from neutral and then to proper gear position, a disc V is mounted between the cams anchored to the gear case by a pin V<4>. In a cross slot V<3>, Fig. 5. are arranged spring-pressed pointed plungers V<1>, V<2>, which engage deep slots in neutral as shown, which interlock, or shallow notches 1 - - 4 which lock the one moved and movable cam in gear position. In a modification, the cams are segments only. The arms q, q<1>, Fig. 4, may be connected to levers w<11>, w<12>, Fig. 10, which comprise spring parts w<9>, w<10> normally loched in the cross slot of a gate w<5>, Fig. 12, and having recessed end pieces above the gate. A spring lever w selects and operates. In Fig. 14 is shown a selector enclosed within the gear-box. A rod y is moved axially to engage a toothed sector y<1> with teeth r<4> or t<4> upon the cams, and is turned to operate the selected cam.