GB1094811A - Improvements in or relating to gear-boxes - Google Patents

Abstract

1,094,811. Change speed gear. A. E. C. Ltd., and E. J. RIDDLE. Jan. 6, 1965, No. 620/65. Heading F2D. A change speed gear for vehicles providing ten or twelve forward ratios and reverse comprises a two-speed planet or countershaft gear in series with a five or six-ratio main gear having aligned input and output shafts 13, 15 which may be clutched together at 20 for direct-drive and two countershafts 16, 17 driven at different speeds from the input shaft 13 through gear pairs 25, 26; 28, 29. Both countershafts carry identical gears 30, 31 meshing pinions 34, 35 fast with the output shaft 15 and the gears 30, 31 are selectively clutched at 32 to their countershafts to provide four reduced ratios. A gear 40 which meshes a pinion 42 on the output shaft 15 may be clutched at 41 to the countershaft 16 for overdrive. Reverse is obtained by sliding a pinion 43 on the countershaft 17 into mesh with a pinion 46 on an idler shaft 18 which carries a pinion 47 in constant mesh with the output pinion 35. The ratios may be in geometric progression. In Fig. 4 (not shown), the axial length of the gear is reduced by arranging the clutch operating sleeve 20 on the other side of the gear 35, the clutch comprising pins which pass through holes in the gear 35 and engage recesses in the gear 25. In this embodiment the reverse pinion is fixed on the countershaft 17 and the pinion on the idler shaft is axially slidable. In Figs. 5-7 (not shown) the overdrive gear pinion 40 is omitted and reverse is obtained by clutching a gear in permanent mesh with an output gear to the idler shaft, the direct-drive shift fork being extended to oparate this clutch. A power-takeoff may be taken from one of the countershafts.