Patent GB-1142052-A (GB)
Title: Change-speed transmission
IPC: F16H3/66
Filed: 1966-08-09
Abstract: 1,142,052. Change speed gear. FORD MOTOR CO. Ltd. 9 Aug., 1966 [14 Oct., 1965], No. 35507/66. Heading F2D. In a change speed planet gear for a motor vehicle wherein two elements 22, 24 of a planet train are both clutched at CL-2, CL-3 to an input shaft 64 for direct drive, a one-way clutch C-4 is provided between the input shaft 64 and one of the clutches to permit one element to be driven from the input shaft 64 through an overdrive unit 100 without disengaging the clutches CL-2, CL-3. As shown two sunring planet trains 18, 20 have interconnected suns 24, 32 and the output carried planets 28 of the first train mesh the sun 24 and a ring gear 22 whilst the planets 36 of the second train mesh the sun 32 and a ring gear 30 fast with the output shaft 54. For one-way low ratio an intermediate shaft 96 which is driven from the input shaft 64 through a hydrodynamic torque converter 10 is clutched at CL-3 to the ring gear 22 and the second carrier 34 is held by a one-way brake C-5 to compound both trains. For two-way low ratio the carrier 34 is held by a friction disc or band brake B-2. Intermediate ratio through the first train alone is provided by keeping the clutch CL-3 engaged and holding the sun 24 by a brake B-1. For directdrive both clutches CL-2, CL-3 are engaged to lock-up the first-train. Overdrive ratio is provided by additionally engaging a clutch CL-1 which connects the input shaft 64 to a ring gear 100 of the overdrive unit. The ring gear 100 drives, through intermeshed idlers 108, 110, a gear 102 fast with the sun 24 at a speed in excess of that of the ring gear 22, the one-way clutch C-4 over-running. Reverse through the second train alone is provided by engaging the clutch CL-2 and brake B-2. In Fig. 6 (not shown) the clutch (CL-1<SP>3</SP>) connects the ring gear (100<SP>3</SP>) of the overdrive unit to the intermediate shaft (96<SP>3</SP>). In Figs. 4 and 5 (not shown) the overdrive unit comprises a planet train having input carried planets (108<SP>1</SP>) meshing a fixed ring gear (100<SP>1</SP>) and a sun gear (102<SP>1</SP>) fast with the interconnected suns of the first and second trains. In Fig. 4 the clutch (CL-1<SP>1</SP>) connects the planet carrier of the overdrive unit to the input shaft (64<SP>1</SP>) whilst in Fig. 5 the clutch (CL-1<SP>2</SP>) connects the planet carrier of the overdrive unit to the intermediate shaft (96<SP>2</SP>). In Fig. 7 (not shown) the overdrive unit is identical to that of Fig. 1 but the planet train comprises stepped suns (242, 244) selectively clutched to the intermediate shaft (232) and intermeshed planets (246, 248) on a reaction carrier (250) which planets mesh the suns (242, 244) and an output ring gear (240). The sun (242) is clutched to the intermediate shaft (232) for all forward ratios and the carrier (250) is held for low ratio, the sun (244) is held for intermediate ratio, the sun (244) is clutched to the intermediate shaft for directdrive and is driven through the overdrive unit for overdrive ratio. For reverse ratio the sun (244) is clutched to the intermediate shaft and the carrier (250) is held by a brake (B-2<SP>4</SP>).