GB387016A - Improvements in and relating to variable-speed gearing - Google Patents

Abstract

387,016. Variable-speed gearing; ratchet clutches. HOLLOWS, L., 44, Parr Street, St. Helens, Lancashire. Aug. 7, 1931, No. 22351. [Class 80 (ii).] In variable-speed gearing for motor vehicles, employing free-wheel clutches at least at the higher speed, a pinion B, Figs. 1 and 2, on the driving-shaft A engages quadrants d on levers D<1>, D<2> pivoted in a free cage C and frictionally engaging an outer driven drum F. In a second free-wheel clutch, Figs. 3 and 4, the levers 3a, 3b engaging the pinion 1 on the shaft A carry rollers 2a, 2b which are adapted to be brought, by axial movement of the inner parts of the clutch, into alternative engagement with oval or other non-circular drums 6A, 6B. An operating-sleeve M, Fig. 1, actuated by a pedal a, Fig. 6, has lost-motion connection with the axially slidable cage C, its lugs m<1> engaging lugs d<3> on the levers D<1>, D<2>, when these latter are withdrawn axially from the drum F, so as to prevent their radial movement. When the cage C is returned to the position shown, the inner surfaces d<1> of the levers engage a camplate H on the drum F so that the levers are expanded, to initiate frictional action, against the action of spring L. While the drum F overruns the shaft A, the frictional action is insufficient to transmit appreciable torque with normal pressure upon the pedal a. When the shaft A accelerates, the pinion B rotates the levers to clutching position. This clutch may, however, be replaced by any other type of clutch. A positive free-wheel drive is similarly obtained in the high and second speed clutch, Figs. 3 and 4, in which, however, the springs 4 assist clutching action and bevel-edged rollers 2a, 2b on the levers 3a, 3b engage non- circular surfaces on drums 6A, 6B during movement to operative position. The clutch, Fig. 1, drives the low-speed pinion G constantly engaging a pinion 8, Figs. 1 and 3, on the layshaft 10. The clutch, Fig. 3, drives alternatively the second-speed drum 6A, geared to the lay-shaft gear 5a, and the high-speed drum 6B secured to the driven shaft T. A double pinion 9 is slidable on the shaft 10 by a fork 11 to engage directly with the drum 6B, for forward reduced speeds, or through idlers 12 for reverse, this movement being possible only when the clutch, Fig. I, is engaged within the drum F by depression of a pedal a, Fig. 6, secured to the rock-shaft Q against the action of a spring ql. The pedal a is pivoted to a link b sliding on a pin e and provided with a hole bl engaged by a rod dx carrying the gearlever c, so that when the latter is in the position shown it can be moved to operate the clutch, Fig. 2, through a push-rod 13a for second and top speeds, while the clutch, Fig. 1, is locked out of gear ; with the gear-lever c in either of its left-hand low-speed and reverse positions, the pedal a can be moved to engage the clutch, Fig. 1, and by increased pressure upon the pedal, the pressure of the levers D<1>, D<2> upon the cam H becomes sufficient to lock the clutch for engine braking.