TM-9-2520-234-35 Technical Manual for M109 Transmission XTG-411-2A Download

PAR 16 DESCRIPTION AND OPERATION OF CHAP 2, SEC II MAIN TRANSMISSION ASSEMBLY to clutch hub assembly 35 in such a way that it can be locked to shaft and carrier 2 (fig. 378, fold-out 7) or locked in sta- tionary position. b. Output Clutch Components (fig. 377, fold-out 6). Output clutch includes hub 46, seven internal-splined 47, and seven external-splined 48 plates, hub as- sembly 35, piston assembly 40, springs 44 and retainer 43. Hub 46 is splined to shaft and carrier assembly 2 (fig. 378, fold-out 7). Plates 47 (fig. 377, fold-out 6) have internal splines which engage ex- ternal splines on hub 46. Plates 48 have external splines which engage internal splines in hub assembly 35. Hub 35 is supported at one end by ball bearing 95 (fig. 375, fold-out 4) and, at the other end by sun gear assembly 52 (fig. 377, fold-out 6), which rotates on ball bearing 50. Pis- ton assembly 40 operates in a bore in hub assembly 35. Springs 44, retained by re- tainer 43, push the piston to released position. c. Geared Steer Clutch Components (fig. 377, fold-out 6). The geared steer clutch includes six disks 63, seven plates 62, piston 61 and anchor 65. The internal splines on disks 63 engage external splines on hub assembly 35. The external splines on plates 62 engage internal splines on anchor 65. Piston 61 operates in a bore of the transmission housing (right piston operates in a bore of the end cover). Anchor 65 is held stationary by bolts. Clutch reaction plate assembly 66 serves the steer clutch and brake jointly and is anchored by the same bolts which retain anchor d. 65. - Operation of Geared Steer Planetary, Output Clutch and Geared Steer Clutch (figs. 374. 377, 378, fold-outs 3, 6, 7) (1) Planetary gearing and two clutches operate in two ways to transmit rotation to output shaft 18 (fig. 374, fold- out 3). Under one condition, torque is transmitted at a 1 to 1 ratio. Under the other condition, there is a speed reduction [from transfer driven gear shaft 4 (fig. 380, fold-out 9) to output shaft 18 (fig. 374, fold-out 3)] of 1.477 to 1. The right and left systems have identical and simul- taneous functions during straight travel of the vehicle. They operate separately during steer. (2) During straight travel in all gears, except first and reverse 1, drive is direct. In first gear forward and reverse 1, there is a speed reduction through the system. This applies to the right and left out puts simultaneously during straight travel. During steer, drive is transmitted to one output while the other output is either stopped or slowed. The vehicle steers toward the stopped or slowed side. (3) Two methods of steering are employed — clutch-brake steer (first, sec- ond and reverse 1 gears) and geared steer (third, fourth and reverse 2 gears). In clutch brake steer, one output drives while the other is disengaged and braked. In geared steer, one output is slowed by speed reduction in the steer planetary while the other output continues to drive at 1 to 1 ratio. Thus, during geared steer, the right- and left-output clutches and geared steer clutches operate singly. A geared steer clutch is applied at one side of the transmission while an output clutch is applied at the opposite side. (4) When hydraulic pressure is applied to the output clutch, the piston assembly 40 (fig. 377, fold-out 6) com- presses plates 47 and 48 against the reaction plate surface of sun gear assem- bly 52. This locks sun gear 52 and shaft and carrier assembly 2 (fig. 378, fold-out 7) together. Ring gear 14 then drives the carrier at 1 to 1 ratio. When hydraulic pressure is applied to the geared steer clutch, piston 61 (fig. 377, fold-out 6) compresses plates 62 and disks 63 against reaction plate assembly 66. This locks sun gear assembly 52 stationary. Ring gear 14 (fig. 378, fold-out 7) then drives shaft and carrier assembly 2, at reduced speed, around the stationary sun gear. Speed reduction (from output transfer driven gear to transmission output coupling) is 1.477 to 1. When either clutch is released, springs push its piston to released position. Change 2 17