Patent GB-342176-A (GB)
Title: Improvements in and relating to clutches
IPC: F16D41/08
Filed: 1930-03-03
Abstract: 342,176. Free-wheel clutches. THOMAS, G. F., 14, Lockhart Avenue, Camberwell, and LEAPER, T. D., 23, Lambeth Place, St. Kilda, both in Victoria, Australia. March 3, 1930, No. 6958. Convention date, April 2, 1929. [Class 80 (ii).] In a bi-directional over-running clutch comprising balls or rollers 4 mounted in a cage 6 between outer and inner members 2, 3 and engaging cam surfaces 7 formed in the outer member 2, presser members 13 arranged in a peripheral groove in the member 2 are adapted to be moved radially inwards so as to press the rollers against the member 3, whereby they are caused to roll to the appropriate ends of the surfaces 7. As shown in Figs. 1, 2, a control ring 31 rotating with and movable axially on the member 2 is connected by pins 32 to slides 18 movable in longitudinal bores in the member 2, each slide having a striker 17 adapted to depress a corresponding member 13. The slides are normally maintained in inoperative position by springs 30. Each slide is provided with a lug 21 entering a recess 22 in the cage 6, the recess having a wide inner part 23, Fig. 6, and a narrow outer part 24. The lug 21 is bevelled to correspond with a bevelled detent 27 extending from the cage into the part 23, so that the springs 30 act on the cage through the members 21, 27 to urge it in a direction tending to maintain the rollers 4 in driving engagement with the appropriate ends of the surfaces 7. Extensions 29 on the lugs 21 prevent the detents 27 from riding over the lugs during over-running. When the ring 31 is moved to the full extent to the right, that is to neutral position, the lugs 21 are received in the narrow portions 24 of the recesses 22. If, during over-running of the driven member, the ring 31 is moved partially to the right until the strikers 17 depress the members 13, and then released, the rollers will roll to the opposite ends of the surfaces 7, so that the member 2 or 3 which was formerly driving now acts as a brake. As applied to a motor vehicle, the clutch is fitted between the gearbox and propeller shaft and the ring 31 is actuated from the main clutch pedal through connections including a rocker having a two-stage cam slot so that the main clutch is partially engaged while the members 13 are still depressed. Alternatively, the detent 27 may be formed on a plunger urged towards the lug 21 by a spring, or spring-pressed ball detents mounted in the cage may be adapted to engage recesses in the member 2 so as to tend to maintain the cage in its extreme positions. In the form shown in Figs. 14, 15, the members 13 are depressed only during the movement of the control ring 31 from neutral to clutching position. Blocks 56 arranged in longitudinal slots 57 in the ring 31 so as normally to move therewith are each provided with a slot 65 receiving the head 66 of a pin 67 mounted in a radial hole in the member 2 and engaging a stud 71 on the corresponding member 13. As the ring 31 is moved to the right, the blocks move therewith until arrested by the engagement of the heads 66 with the left-hand ends of the slots. As the ring continues to move, strikers 17<1> on the ring ride over shoulders 73 on the blocks without, however, depressing the heads 66. On the return movement, the blocks move with the ring until the heads 66 engage under the shoulders 73, and, as the ring continues to move, the strikers 17<1> cause the members 13 to be depressed. Recesses 22<11> shaped as shown in Fig. 17 and having detents 27<11> are formed in the ring 31 to co-operate with lugs 21<11> formed by the flattened ends of pins 79 secured to the cage 6 and passing through elongated holes 81 in the member 2. The cage is urged in the appropriate direction by spring-pressed balls 86 engaging the pins 79. The ring 31 is actuated from the main clutch pedal 88 through a rod 89, Fig. 32, and lever 91, an adjustable spring 95 being fitted on the rod 89 so as to relieve the pins 79 from strain when the pedal is depressed after the parts have been positioned so as to use the engine as a brake. A dog clutch 99, 101, Fig. 32, enables the members 2, 3 to be locked together when required.