Patent GB-141801-A (GB)
Title: Improvements in change speed mechanism
IPC: F16H61/02
Filed: 1919-01-20
Abstract: 141,801. Landis, A. B. Jan. 20, 1919. Relay or power apparatus; interlocking; brakes, counterpressure.-Variable-speed and reversing gearing is controlled by power taken from the driving- shaft, such power also disconnecting a main friction clutch prior to each speed change. A shaft 125, Fig. 8, is turned for each speed change, and carries cams which are moved selectively into operative position. Power passes from a shaft 21, Fig. 2, through the main clutch 24 to the driving-shaft 33 of the change-speed gear. A sun gear 70 secured to the shaft 33 meshes with planet gears 71 carried by a spider or housing 66 secured to the driven shaft 67. Gears 77 connected by sleeves 76 to the gears 71 mesh with other planet gears 78, Fig. 6, which are secured to pinions 227, Fig. 2. The gears 78 mesh with a loose sun gear 80 secured to a brake drum 81. The gears 71 and 227 mesh with internally toothed rings 73, 228, respectively. The first and second speeds and reverse drive are effected respectively by holding against rotation the elements 73, 81, 228. The third speed is a solid drive obtained by closing a clutch 85. The clutch 85 engages first a cone 100 yieldingly secured to the housing 66 so as to allow @eeth 110 afterwards to engage teeth 105 on the housing for positive driving. The clutch is shown in its open position. To close it, a collar 84 is moved to the left until pivoted spring dogs 88 fly outwards into a groove 90 in the collar, bringing heels 97 on the dogs against the end of a fixed collar 63. A spring 99 assists the reverse operation. The elements such as 228, which are held, are first gripped frictionally by a band such as 82<a>, Fig. 6, and afterwards by a spring-pressed positive-locking member 170 operated by a latchbar 221. The band is in two parts between which the stress is distributed. A rod 167 screwed info the end of the upper half passes through the end of the lower half and bears upon a curved member 173. which at its opposite end 174 bears upon a fixed member 175. The clutch 85 is operated through a rock-shaft 95 from a pair of cams 178, 179, Fig. 8, upon the shaft 125. The main clutch 24 is operated from a rock-shaft 42 having a lever 190 engaged bv a cam 195a on the shaft 125. A bevel-gear 131 loose on the end of the shaft 125 is driven continually from a worm 126, Fig. 2. When a change of speed is to be carried out, a control shaft 111, Fig. 8, is turned by pulling a rack-bar 118. This selects and moves one of the cams on the shaft 125 by way of cams and levers 181, 151, 225, and 224. A one-revolution clutch 134 is thrown into action, causing the shaft 125 to turn once round and be stopped by a spring roller 146. The lever 190 is first rocked to disconnect the clutch 24. This plate clutch 24, Fig. 2 and 3, is adapted by its operating-gear to allow its driven shaft to overrun, or, alternatively, as applied to a motor vehicle, to allow the engine to be used for braking. Its driving and driven elements 24, 31 have ribs 25, 30 fitting in grooves in the driving and driven friction plates 27, 29. The clutch is put into and out of action from the shaft 42, Fig. 8, by a sliding sleeve 35, Fig. 2, having arms 36 engaging the plates. In the configuration shown, a spring 62 presses the plates into action through levers 59 and rollers 57. The rollers project through holes 53 in the sleeve 35 and bear against shoulders 55, which transmit the pressure. When the sleeve 35 is moved to the left to open the clutch, the rollers 57 drop behind a fixed collar 64, which takes the spring pressure. The overrunning effect is produced by the fact that the plates 27 have play at 26, Fig. 3, relative to the ribs 25. There is connexion through pins 197<a> and angular slots 198, Fig. 13, to a ring 196<a> which is moved sideways, and through a lever 192, Figs. 2 and 8, causes a shoulder 230 to catch the lever 190 and hold the clutch disengaged. The overrunning effect can be cut out by operating a pedal 49, Fig. 3, in such a way as to cause a latch 195, Fig. 8, to lock the lever 192 out of action.