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

CHAP 2, SEC II DESCRIPTION AND OPERATION OF PAR 14-16 MAIN TRANSMISSION ASSEMBLY (fig. 377, fold-out 6) is splined to low- range planetary shaft and carrier 27 (fig. 376, fold-out 5) which is supported by ball bearing 20 (fig. 377, fold-out 6) in support 18. c. Operation of Reverse-range Clutch and Planetary Gearing (fig. 377, fold-out 6) (1) When hydraulic pressure is directed to the cavity between piston 60 (fig. 376, fold-out 5) and housing 55, the piston moves against clutch plates 1, 2, 3, and 5 (fig. 377, fold-out 6). This com- presses the plates against support 18 and locks the clutch plates together. Ring gear assembly 4 is thus prevented from rotating and becomes the reaction mem- ber of the planetary gear set. (2) The reverse-range gearing is compounded with the low-range gearing to obtain the desired direction of rotation and speed reduction. The reversing of ro- tation occurs in the low-range gear set, with some speed reduction. Further speed reduction occurs in the reverse-range gearing. This is because reverse-range sun gear 39 (fig. 376, fold-out 5), being the driving member of the reverse-range gear set, must first be rotated. It is ro- tated by low-range ring gear 38 to which it is connected. In turn, low-range ring gear 38 derives its rotation (reversed) from low-range pinions 30 which are driven by low-range sun gear 62 (fig. 375, fold-out 4). The reaction member in the low-range gear set under these conditions is the moving carrier 27 (fig. 376, fold-out 5). Speed reduction is 4.77 to 1. (3) When hydraulic pressure is released from the piston, springs 61 push the piston into housing 55. This allows the clutch plates to separate and rotate freely, releasing the clutch. 15. OUTPUT TRANSFER GEARS AND SHAFT a. Components (figs. 377, 378, 379 and 380, fold-outs 6, 7, 8 and 9). The out- put transfer gearing includes a 50-tooth output transfer drive gear 26 (fig. 377, fold-out 6), a 65-tooth output transfer driven gear 49 (fig. 379, fold-out 8) and a driven gear shaft 4 (fig. 380, fold-out 9). The drive gear has internal splines which engage the low-range planetary carrier shaft. The driven gear has internal splines which engage shaft 4. Both gears are supported by straight roller bearings 25 (fig. 377, fold-out 6), 27, 35 (fig. 378, fold-out 7) and 1 (fig. 380, fold-out 9). The bearings are retained by supports 24 (fig. 377, fold-out 6), 28, 34 (fig. 378, fold-out 7) and 2 (fig. 380, fold-out 9) which are bolted to the transmission rear housing. b. Operation (figs. 377, 378, 379, 380, fold-outs 6, 7, 8 and 9). Output transfer drive gear 26 (fig. 377, fold-out 6) is ro- tated clockwise (viewed from the left of the transmission). Driven gear 49 (fig. 379, fold-out 8) is meshed with drive gear 26 (fig. 377, fold-out 6) and rotates counter- clockwise. This rotation is transmitted to the geared steer planetary ring gears splined to each end of shaft 4 (fig. 380, fold-out 9). Thus the output of the range gearing is reversed and transmitted to the geared steer planetary gear sets at the left and right of the transmission. The speed reduction in the output transfer gearing is 1.3 to 1. 16. RIGHT- AND LEFT-GEARED STEER PLANETARIES, OUTPUT CLUTCHES AND STEER CLUTCHES a. Geared Steer Planetary — Components (figs. 377, 378, 380 and 381, fold-outs 6, 7, 9 and 10) Note. All key numbers, below, refer to figs. 377 and 378, fold- outs 6 and 7, which illustrate the left components. The right com- ponents are identical and are illus- trated in figs. 380 and 381, fold- outs 9 and 10. The geared steer planetary includes ring gear 14 (fig. 378, fold-out 7), four pinions 6, sun gear assembly 52 (fig. 377, fold-out 6), four spindles 11 (fig. 378, fold-out 7) and carrier 3. Ring gear 14 is splined to driven gear shaft 4 (fig. 380, fold-out 9). Pinions 6 (fig. 378, fold-out 7) rotate on needle bearing rollers 7 on spindles 11 which are mounted in carrier 3. Sun gear assembly 52 (fig. 377, fold-out 6) is splined 16 Change 2