GB311009A - Improvements in and relating to controllable free wheel mechanism for motor road vehicles or other apparatus - Google Patents

Abstract

311,009. Toothill, C. Feb. 4, 1928. Clutches, ratchet; variable-speed toothed gearing; facilitating changing speed.-In a free-wheel clutch for motor-vehicles, of the type comprising caged rollers disposed between an external drum and an internal polygonal member and controlled by a sliding key coacting with the cage, spigotended rollers are loosely carried by their spigots in the cage, which has a recess or recesses engageable at one side or the other by the bit of the slidable key or keys to determine declutching or forward, reverse, or bidirectional drive. The clutch may be placed before or behind the gearbox or may be associated with the gear-trains. The engine-shaft S, Figs. 1 and 2, carries the polygonal members H with flat or slightly convex sides H', and the propeller-shaft S<1> the drum D. The spigots R<1> of the rollers R have radial play in holes C<1> or open slots in the cage C. which has on one or both sides a notch C<2> normally engaged by the bit K<3> of a key K, revoluble with the member H and actuated by a collar K<1>. While the bit K<3> engages the notch, unidirectional overrun is allowed. The key is withdrawn to allow the engine to be used as a brake, the main clutch being " slipped " to reduce shock. To avoid the necessity for easing the main clutch, the collar K<1> may act through a spring O, Fig. 4, to bring a disc A against a flange on the drum D just prior to disengagement of the hit K<3>, in order to synchronize the shafts S, S<1>. Two keys, engageable with opposite faces of two notches, may be used to set the cage for forward, reverse, or bidirectional drive, Fig. 3 (not shown). Three such clutches are used with the direct drive and third and second speeds of the four-speed gearbox shown in Fig. 5, the first-speed gear having a free wheel clutch without cage-control. The reverse train is not shown. One or other of the key-bits K<3> of each clutch is always in engagement, so that, whichever gear (except the top) is driving, engine-brake is available on the next higher gear, the lower gears all overrunning. On the engine and tail shafts S, S<1> the drums D drive, but on the lay-shaft S<2> the polygonal inner members drive. The cage C, rollers R, and member H may form a unit reversible to equalize wear on the faces H<I>.