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Pic. 19. The scheme of the gearbox: 1. Host (primary) shaft; 2. Slave (secondary) shaft; 3. Gear wheel of constant engagement of the input shaft; 4. Synchronizer ring of IV gear; 5. Sliding clutch of the synchronizer of III and IV gears; 6. Fork of inclusion of III and IV transfers; 7. Gear and ring gear of the synchronizer of the III gear; 8. Gear and ring gear of the synchronizer of the 2nd gear; 9. Sliding clutch of the synchronizer of I and II gears; 10. Fork of inclusion of I and I transfers; 11. Gear and ring gear of the synchronizer of the 1st gear; 12. Reverse gear; 13. Clutch hub synchronizer V transmission; 14. Sliding clutch synchronizer V transmission; 15. Fork of inclusion of V transfer and a backing; 16. Gearshift lever; 17. Gear and ring gear synchronizer V transmission; 18. Bushing gear V gear; 19. Oil deflector; 20. Speedometer drive gear; 21. Flexible coupling flange; 22. The rod of the fork of the inclusion of V gear and reverse; 23. The rod of the fork of inclusion of III and IV gears; 24. The rod of the fork of inclusion of I and II gears; 25. The switch of a lantern of a backing; 26. Reverse gear of the gear block; 27. Intermediate reverse gear; 28. Block gears V transmission and reverse; 29. The axis of the intermediate reverse gear; 30. Gear wheel of the 1st gear of the intermediate shaft; 31. The blocking ring of the synchronizer of the I transfer; 32. Synchronizer coupling hub for I and II gears; 33. The blocking ring of the synchronizer of the II transfer; 34. Gear wheel of the second gear of the intermediate shaft; 35. Gear wheel of the III gear of the intermediate shaft; 36. The blocking ring of the synchronizer of III transfer; 37. The hub of the synchronizer coupling of III and IV gears; 38. The blocking ring of the synchronizer of IV transfer; 39. Gear wheel of constant engagement of the intermediate shaft.
The five-speed gearbox is based on a four-speed gearbox, so the schemes for transmitting torque from the input shaft to the secondary in all gears, with the exception of fifth gear and reverse, are similar to a four-speed gearbox. That is, the torque from the crankshaft of the engine through the clutch is transmitted to the input shaft 1 and through gears 3 and 39 of constant engagement to the intermediate shaft. The intermediate shaft gear block has constant engagement with gears 7, 8, 11 of the third, second and first gears of the output shaft. Therefore, they rotate from the intermediate shaft both with the gear engaged and with the gear disengaged. In addition, together with the intermediate shaft, the gear block 28 rotates, from the large crown of which the rotation is transmitted to the gear 17 of the fifth gear. Since the gears 7, 8, 11, 17 are freely seated on the output shaft 2, when the gear lever is in the neutral position, none of these gears transmits torque to the output shaft.
When starting the car from a place and overcoming difficult sections of the road, 1st gear is engaged (see shift lever movement diagram). In this case, the sliding clutch 9, engaging with the ring gear of the synchronizer of gear I of the first gear, connects the hub 32 with gear II. The torque from the gear II through the clutch 9 and the hub 32 is transmitted to the secondary shaft 2. The transmitted torque increases in accordance with the gear ratio by 3.67 times.
With further acceleration of the car, they shift from first gear to second. In this case, the clutch 9 connects the hub 32 with the ring gear 8 of the second gear and the torque from the gear 8 through the clutch 9 and the hub 32 is transmitted to the output shaft. The amount of torque is slightly reduced and, compared with direct transmission, will be increased by 2.10 times; vehicle speed increases.
When switching to third gear, the sliding clutch 5 of another synchronizer connects the hub 37 to the crown of the gear 7. The torque is transmitted from the gear 7 through the clutch 5 and the hub 37 to the secondary shaft 2. The amount of torque decreases slightly, and the speed increases.
When the fourth gear is engaged, the clutch 5 engages with the ring gear 4 of the input shaft, that is, it directly connects the primary and secondary shafts of the gearbox. In this case, the speed of rotation of the primary and secondary shafts will be the same and the amount of torque does not change and will practically correspond to the torque on the engine crankshaft. This transmission is called direct.
When the fifth gear is engaged, the sliding clutch 14 connects the hub 13 with the ring gear of the gear 17. The torque will be transmitted from the input shaft 1 through the constant mesh gears 3 and 39 to the intermediate shaft. From it to the block 28 of gears and from the large crown of the block to the driven gear 17 of the fifth gear, then through the clutch 14 and the hub 13 to the output shaft 2. In this case, the torque will be minimal and the speed maximum.
Reverse gear is engaged by moving the shift lever to the right, then pushing it down and moving it back in the direction of the vehicle. In this case, the intermediate gear 27 of the reverse gear engages with the small crown 26 of the gear block and with the crown of the reverse gear 12. When moving the intermediate gear 27, the head of the rod presses the ball of the switch rod 25 and sinks it. The reverse lamp circuit closes and the lamp indicates reverse gear in white.
Gearbox parts are lubricated with gear oil, which is poured in an amount of 1.55 liters under the edge of the filler hole. As the shafts and gears rotate, oil mist is generated. Oil through the radial holes in the driven gears 7, 8,11 and 17 flows to the landing belts of the secondary shaft, on which these gears are located. Due to the grooves on these belts, an oil film is formed, which does not allow direct contact of the metal surfaces of the gears and the shaft.
The tightness of the gearbox housing is provided by oil seals of the primary and secondary shafts and gaskets that are installed between the housing and the bottom, as well as the back cover. To reduce the oil pressure on the driven shaft oil seal, an oil slinger washer 19 is installed on the shaft.
Axial forces arising from the transmission of torque through helical gears are perceived by shaft ball bearings, which are fixed in their sockets with adjusting rings (intermediate bearing of driven shaft with locking plate), and on the shafts with spring washers and circlips.
The simple design of the gearbox, constant mesh helical gears and synchronizers ensure a durable and quiet operation of the gearbox. Its maintenance is reduced to a minimum: checking the level and changing the oil (see fig. 14).
To check the oil level, unscrew the plug 54 (see fig. 18), the oil level should be at the lower edge of the hole. Drain the used oil through the hole in the bottom cover of the gearbox. It closes with a cork with a magnet.
When the parts of the retainers, blocking rings and synchronizer couplings are worn out, fuzzy engagement of gears and even their spontaneous disengagement is possible. Wear of these and other parts occurs when the gearbox is used for a long time or when shifting gears when the clutch is not fully disengaged. In this case, partial transmission of torque from the gear continues, and when they engage, the gear teeth experience shock loading. Particularly intensive wear of parts occurs when the oil level or its leakage decreases. This malfunction is possible when the oil seals of the input and secondary shafts are worn out or the bottom or rear covers of the gearbox are loosened.
When parts are worn to the limit, noises occur in the gearbox. With such a malfunction, further operation of the car is not permissible, since damage to the gearbox parts is possible.
To prevent premature failure of the gearbox, you should regularly, every 10,000 km of run, check and, if necessary, add oil, and also check visually for oil leaks.
During operation of the gearbox, oil from the effects of temperature, transmission loads, oxidation and contamination with wear products "getting old", so it should be replaced every 60,000 km.