Patent GB-732813-A (GB)
Title: Improvements in or relating to tractor power-transmitting mechanism
Inventor: FERGUSON HENRY ANTHONY
IPC: B60K17/08
Filed: 1953-07-24
Abstract: 732,813. Change-speed gear. INTERNATIONAL HARVESTER CO. July 24, 1953, No. 20595/53. Class 80 (2). [Also in Group XXXI] A primary transmission housing 37 forming part of a tractor frame has front. and rear bulkheads 47, 45 defining forward, middle, and rear compartments, 41, 42 and 44, the two bulkheads having aligned openings A and B for a main drive-shaft assembly 21, 22, a longitudinallyextending bracing wall 51 connecting the bulkheads 47, 45, and adapted to provide a power take-off drive-shaft housing, isolated from the upper portion of the middle compartment. In the construction shown, the wall 51 is of tubular cross-section (Fig. 3, not shown) and surrounds the power take-off shaft 65. Gears 63, 64 in a housing 48 connect the shaft 65 with the shaft 22, which is hollow and is rigid with a back plate 23 of the normal transmission clutch C and is thus permanently connected with the engine shaft 19. The driven member 28 of the clutch C is rigid with the shaft 21, which is rigid with a shaft 115 carrying the sun-wheel 124 of a torque amplifier unit 53. The sun-wheel 124 engages planet wheels 123 each of which is rigid with a planet wheel 122 engaging a sun-wheel 88 carried by the output shaft 87 of the primary transmission housing. The torque amplifier unit is normally inoperative by virtue of a clutch 52. The driving disc 113 of the clutch 52 is splined to the shaft 115 but the driven backing plate 108 is keyed to a tubular extension 105 of the carrier 103, 96, 105 of the planet wheels 122, 123. When the clutch 52 is engaged the planet carrier and output shaft 87 thus run at engine speed, but when the clutch is disengaged the planet-wheels 122, 123 are effective to raise the gear-ratio between the shafts 115 and 87. In the latter case, rotation of the planet-carrier is prevented by the action of a one-way clutch 104. The output shaft 87 is connected by gears 89, 92 to a counter-shaft 82 of a change-speed gear contained in a housing 35. A gear 91 rigid with the shaft 87 transmits power to a belt pulley (not shown). The power take-off shaft 65 is connected to a shaft 65a rotatable within the countershaft 82. A casing 72 for the torque amplifier unit has a spigot mounting in an end wall 35a of the change-speed gear housing 35. This mounting is strengthened by an integral flange 78 of the casing 72 which abuts the end wall 75. The other end of the casing 72 has a spigot 80 mounted in the opening B of the bulkhead 45. The primary housing 37 and the housing 35, are held in register by a circle of dowels 38, and are secured by a circle of cap screws (39, Fig. 1, not shown). The interior of the casing 72, the lower portions of the rear and middle compartments 44 and 42 and the gear housing 48, are connected by suitable ports. Flow of oil from these chambers to the upper portion of the middle compartment is prevented by seals 107 and 58, and to the forward compartment 41 by seal 59. The clutch 52 is disengaged by the action of a hand lever (Fig. 1, not shown) having a catch to retain it in the disengaged position. The lever is connected to a shaft 109 which is connected to a sliding bearing 117 adapted to coact with clutch-operating levers 118.