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

CHAP 2, SEC II DESCRIPTION AND OPERATION OF PAR 11-13 MAIN TRANSMISSION ASSEMBLY 66 push piston assembly 67 into housing assembly 73, allowing the clutch plates to separate and slip freely. (3) The governor is a “fluid velo- city” type. The governor ring, riveted or welded to the left end of housing 73, is kept filled with oil, retained in the ring by centrifugal force during rotation. The oil thus moves at virtually the same speed as does the ring. The pitot tube 76 is posi- tioned so that its open end faces against the movement of the oil in the governor ring. The opposite end of the pitot tube connects with the hydraulic control sys- tem. Pressure in the governor line thus varies with the speed at which oil is thrown into the pitot tube by the rotating ring. 12. INTERMEDIATE-RANGE CLUTCH AND PLANETARY GEARING a. Intermediate-range Clutch Components (fig. 376, fold-out 5) (1) Intermediate-range clutch in- cludes a clutch housing 3, four internal- splined 4 and three external-splined 5 plates, apply plate 7, spring 8 piston 9 and piston housing 14. External splines on ring gear assembly 6 serve as the clutch hub. (2) Clutch housing 3 is anchored, against rotation, in the transmission hous- ing. Plates 5 and apply plate 7 engage slots in housing 3. Plates 4 engage exter- nal splines on ring gear assembly 6. Pis- ton housing 14 is anchored in transmission housing by bolt 42 (fig. 375, fold-out 4). Piston 9 (fig. 376, fold-out 5) works in a bore of housing 14 on ring seals 11 and 12. b. — Intermediate-range Planetary Gearing Components (fig. 376, fold-out 5) (1) Planetary gearing for this range includes carrier 18, four 18-tooth pinions 22, spindles 19, a 36-tooth sun gear 61 (fig. 375, fold-out 4) and a 72-tooth ring gear assembly 6 (fig. 376, fold-out 5). (2) Pinions 22 or 64 rotate on bearings 23 or 65 and are supported by spindles 19 in the carrier. Sun gear 61 (fig. 375, fold-out 4) is splined to turbine shaft 2. Ring gear 6 (fig. 376, fold-out 5) has internal teeth and external splines. Carrier 18 is supported by bearing 55 (fig. 375, fold-out 4) at one end and is splined to low-range ring gear 38 (fig. 376, fold- out 5) at the opposite end. c. Operation of Intermediate-range Clutch and Planetary Gearing (fig. 376, fold-out 5) (1) When hydraulic pressure is directed to the cavity between piston 9 and housing 14, the piston moves against spring 8 and apply plate 7 and compresses internal-splined 4 and external-splined 5 plates against housing 3. This locks ring gear assembly 6 against rotation. Sun gear 61 (fig. 375, fold-out 4) is the driving member of the planetary. Its rotation drives pinions 22 or 64 (fig. 376, fold-out 5) counterclockwise (viewed from left of transmission) while causing carrier 18 to rotate clockwise. Stationary ring gear assembly 6 is the reaction member and carrier 18 is the driven member. (2) When hydraulic pressure is ex- hausted from the clutch cavity, spring 8 pushes piston 9 into housing 14. This allows the clutch plates to separate and have running clearance, releasing the clutch. (3) The intermediate-range plan- etary gearing is compounded with the low- range planetary gearing to obtain the de- sired ratio. The rotation of carrier 18 is imparted to low-range ring gear 38. Low- range sun gear 62 (fig. 375, fold-out 4) is splined to the same shaft as is intermedi- ate-range sun gear 61. Thus, the rotations, at different speeds, of ring gear 38 (fig. 376, fold-out 5) and sun gear 62 (fig. 375, fold-out 4) impart rotation to the low- range shaft and carrier which is the trans- mission out put shaft. The resulting com- bined reduction of the two planetary systems is 2 to 1. 13. LOW-RANGE CLUTCH AND PLANETARY GEARING a. clutch Low-range Clutch Components (fig. 376, fold-out 5) (1) The low-range clutch includes housing 44, four internal -splined 14 Change 2