Patent GB-386024-A (GB)
Title: Improvements in and relating to reversible free-wheel clutch transmissions
IPC: F16D41/08
Filed: 1931-08-19
Abstract: 386,024. Variable-speed gearing freewheel clutches. BLACKSTOCK, G., 52, Warren Road, Toronto, Canada. Aug. 19, 1931, No. 23416. [Class 80 (ii).] A reversible free-wheel clutch comprises reversible clutching parts, the driving or driven members of which are carried on a torquetransmitting floating member 14, 15, interposed operatively between the driven members (or driving members) of the clutching parts and one of the main clutch elements, and shiftable relatively to that clutch element, by the advance of the driving clutch element, along a limited path of lost-motion between a driving position in one direction at one end of said path, to a driving position in the reverse direction at its other end upon being released by a positivelyacting locking device preferably having means for operating it at will, part at least of this shift being performed without transmission of load, and means operable in consequence of the shift and while the floating member is free of load to throw the clutching parts which have been operating prior to the shift, out of driving condition. The clutch comprises a driving drum 11, and the floating member 14, 15 having wedge faces 37x, 37o between which and the drum 11 are driving rollers 36 and " catch " rollers 38. The floating member is connected with an axially slidable locking collar 20, splined on the driven shaft 2, by a limited lostmotion connection comprising radial tongues 22 on the collar 20 each entering a recess 23x in an exially extending flange 16 on the floating member 15. The recess 23x has two locking pockets, one 24, corresponding to a driving position, Fig. 4, with the drive rollers 36 on their wedging surfaces 37x, the other 23, to a release position, Fig. 3, with the " catch " rollers 38 operating. The tongues 22 drive through pins 49 a ring 48 free on the floating member and carrying strikers 47 which strike off the appropriate rollers whilst they are under no load during the relative movement of the floating member. With the collar 20 locked out, i.e. with the tongue 22 above the dividing wall of the pockets 23, 24, the floating member is taken to either end of the recess 23x without transmitting any drive by the drive or " catch " rollers according to the speed relationship of the coupled parts, the operating roller being struck off before the floating member completes its movement. To locate the tongue 22 truly opposite a pocket 23 or 24 after the rollers have been struck off, the driven ring 48 carries spring fingers 53, 54 which drop into an adjacent pocket during the relative movement and help to pull the floating member to its final position. The rollers, which may be cylindrical, conical, spherical, or of non-circular cross section, are pressed apart by light springs 40 carried by a plate 42 attached to the floating member. In the motor vehicle three-speed and reverse sliding gear of Fig. 1, the roller clutch is for direct drive and the second speed 71, 70 is through a roller free-wheel clutch 74 of normal construction. A normal low speed 65, 62, and reverse 65, 62 and a sliding idler (not shown) are also provided. The locking collar 20 of the roller clutch is operated through a fork 30 by a rail 31 having a pivoted latch 32 to lock it in the release position, the latch being released to allow the rail to move to a locking position under the permanent influence of a spring 33, only on engagement of the free-wheel second gear 62, the operating rail of which has a cam to tilt the latch 32 from the obstructing position. The rail 31 protrudes from the end of the gear box and is moved to the right to release the clutch by a lever connected to the main clutch pedal through a spring, stronger than the spring 33, so that the roller clutch releases whenever the main clutch pedal is depressed. To change up, with the free-wheel second in mesh, the throttle is closed whilst the clutch pedal is momentarily depressed, the roller clutch assumes the drive position where it is locked by the spring 33 and where it freewheels until power is applied. To change down, the throttle is opened whilst the main clutch pedal is depressed, the roller clutch assuming the release position where it is locked, the drive then passing through the free-wheel second. In direct drive, in order to change from the free-wheel condition and use the engine as a brake, the main clutch pedal is depressed momentarily with the throttle open when the roller clutch assumes, and is locked in, the release position transmitting braking and reverse torque only. By installing an intermediate gear with the above-described roller clutch, between the free-wheel second and high, automatic change may be obtained amongst three speeds instead of two. Specification 384,710 is referred to.