Patent GB-636808-A (GB)
Title: Improvements in or relating to transmission gearing for internal combustion power plants
IPC: B61C9/12
Filed: 1948-05-04
Abstract: 636,808. Brakes. COUSINS, R. J. W., and FELL, L. F. R. May 4, 1948, No. 12281. [Class 103 (i)] [Also in Groups XXIV, XXVII and XXXI] In a locomotive multiple-engine power plant, in which each engine of a pair drives the sunwheels of a differential gear through a variablefilling fluid coupling and a uni-directional device, and the power is taken off the planet carrier, means are provided for releasing the abutment of one of the uni-directional devices so as to remove load from the transmission when desired, e.g. when reversing mechanism is to be operated. As shown in Fig. 3, four engines drive, through variable-filling fluid couplings, shaft 5 ... 8 associated in a common gear-box. The shafts 5 ... 8 drive, through bevel gears, shafts 25 ... 28 secured to the sunwheels of differential gears 29, 31. Gears 32, 34, secured to the planet carriers, engage gears 33, 35 which are connected to the sun-wheels of a differential 30, the planet carrier of which, thus receives the output of the four engines, and drives the wheels of the locomotive through a gear train. Reverse rotation of shafts 25 ... 28 is prevented by uni-directional clutches 37 ... 40 which are similar, the operation of clutch 39 being as follows. The shaft 27 has helical splines 51 which engage with internal splines on a disc member 52 which carries dogs 53. When the shaft 57 rotates as shown by the arrow, the member 52 is urged to the right, but when the shaft 27 rotates in the opposite direction the dogs 53 on the member 52 engage with fixed dogs 54, and reverse rotation of the engine driving the shaft 7 is thus prevented. One unidirectional clutch 40 which includes means for releasing the fixed dogs is shown in Fig. 4. The helical splines 61 on the shaft 28 mate with splines on a member 62 provided with dogs 63 and flanges 75, 76, connected by pins 68 carrying pawls. Dogs 64 are formed on an annulus 69 which is bolted through a second annulus 70 to a drum 77 which fits over a second drum 78 bolted to the gear-box 10. A ring 80, preferably of soft metal, is compressed between the annuli 69, 70. The drum 77 has splines 81 on which are mounted clutch-plates 72 and a casing 82, secured to the gear-box 10, has splines 83 carrying clutch plates 73, interposed frictionplates 84 and a pressure-plate 85 being provided. A piston 88 slides in a cylinder 87 subject to vacuum supplied through a conduit 90, operates the clutch through levers 86 and the pressure plate 85, the heels 93 of the levers engaging an annular member 96. Under normal conditions the shaft is turning as indicated by the arrow and the member 62 is urged to the right as shown. On reverse rotation the pawls 67 will engage the dogs 64 and the member 62 will move to the left so that the dogs 63 will engage with the dogs 64 and the member 62 will thus be held stationary. To release the dogs 64, e.g. to enable reverse gearing to be operated, the vacuum acting on the piston 88 is destroyed and the piston moves to the left, thus releasing the multiple plate clutch. Alternatively, the control means may be operated hydraulically or by compressed air. The releasable abutment may be combined with the uni-directional brake described in Specification 628,448.