Patent GB-393298-A (GB)
Title: Improvements in or relating to power transmission mechanism
IPC: B60K17/02
Filed: 1931-10-01
Abstract: 393,298. Facilitating changing speed ; claw clutches. SALERNI, P. M., 23, Carlton House Terrace, London, Oct. 1, 1931, No. 27382. Divided on 390,858. [Class 80 (ii).] Comprises a clutch with positive engaging members or claws 37a, 38a, Fig. 10, prevented from engaging before synchronism by a baulking member or ring 40, as described in Specifications 306,636, 333,222. and 334,503, [all in Class 80 (ii), Gearing, Variable-speed &c.], in which the baulking ring 40 is connected with one of the clutch members such as 37 by a free-wheel clutch 43 in conjunction with a friction slip connection 43b. The clutch is described as a change-speed gear isolating-clutch suitable for incorporation in the vehicle transmission described in Specification 390,858. The clutch member 37 is fast on the driven shaft 36 of the change gear and a suitable roller &c. one-way clutch 43 supports a ring 43a. The baulking ring 40 is supported so that it has a coned frictional engagement at 43b with the ring 43a so that relative turning is possible by slip while the two rings turning together can normally overrun the member 37. The driven clutch member 38 is splined on a tail shaft 39 and is biased towards engagement through a lever 44 by a spring shown at 48 in Fig. 6 of the abridgment of Specification 390,858. The baulking ring 40 has alternate long teeth 41a, Fig. 11, always projecting between the teeth into apertures 42b in the clutch member 38 so that the ring 40 turns with . the member 38 at all times. Between the long teeth 41a on the ring 40 are short teeth 41 adapted to stub against similar teeth 42 on the member 38. The gaps 42b are between the teeth 42 and alternating teeth 42a. This stubbing prevents the member 38 from being advanced to the left into clutch engagement. This happens when the driven member 38 is rotating faster than the driving-member 37, as when a vehicle is coasting. As long as this condition obtains, the rings 40, 43a keep freewheeling over the member 37 and the spring 48 aforesaid is unable to snap the clutch 38 into engagement, but maintains frictional thrust between the coned surfaces 43b. On accelerating the engine, the member 37 overtakes the member 38. The free-wheel 43 grips and throws the rings 43a, 40 forward, that is, downward of Fig. 11, so that the baulking teeth 41 slip clear of the teeth 42 and the aforesaid spring 48 causes the clutch member 38 to snap to the left of Fig. 10 and bring the main clutch teeth 37a, 38a into full engagement with the baulking teeth in the position shown in Fig. 12. It is during this operation that the slip at the cones 43b occurs. In order that the clutch may be engaged at will manually without accelerating, a cam ring 49, Fig. 9, is slidably splined at 42d on and around outside the member 38. In the position of the clutch maintained disengaged by the baulking ring 40 shown in Fig. 11, inclines 49a on the ring 49 are opposite and in line with inclines 49b on the ring 40. On sliding the manual control ring 49 to the left, as by a linkage 51, 50, Fig. 10, these inclines engage so that the ring 40 is forced round downwards of Fig. 11, so as to move the baulking teeth 41 clear of the teeth 42 and allow the main clutch to snap or be moved into engagement.