Open large image in new tab »
1. Gear lever. 2. Lever release spring. 3. Bolt. 4. Lever guide cup. 5. Ball joint lever. 6. Lever guide pin. 7. Flange for fastening the seal of the lever. 8. Lever support ball. 9. Spherical washer. 10. Spring. 11. Inner case. 12. Outer cover. 13. Locking sleeve damper. 14. Damper bushing. 15. Spacer. 16. Thrust cushion damper. 17. Gear lever handle. 18. Lever handle (car VAZ-2103). 19. Shift fork for third and fourth gears. 20. 3rd and 4th shift fork rod. 21. The rod of the fork of switching the first and second gears. 22. Switching fork of the first and second gears. 23. Reverse fork rod. 24. Restrictive bolt. 25. Transmission housing. 26, 27, 28. Blocking crackers. 29. Spring for forward gear lock. 30. Retainer ball. 31. Cover of clamps. 32. Remote bushing of the reverse fork rod. 33. Reverse lock spring. 34. The switch of a lantern of a backing. 35. Reverse fork. 36. Synchronizer clutch hub. 37. Restrictive protrusion of the gear lever.
Four-speed car transmission «Zhiguli» is three-way, since the gears in it are switched on and off using three forks that move two synchronizer clutches and one gear. The fork 22, fixed on the rod 21 with a bolt with a spring washer, serves to shift the first and second gears, and the fork 19, fixed on the stem 20 with a bolt with a spring washer, is used to shift the third and fourth gears. The reverse gear is switched on by the third special fork 35, fixed on the rod 23 with a bolt. The mounting bolts and their spring washers are the same for all forks. At the ends of the rods of the forward and reverse gear forks, there are grooves into which the lower end of the gear lever 1 enters.
The forward gear forks fit into the annular grooves of the synchronizer couplings, and the reverse gear fork fits into the recess of the intermediate gear.
The rods of the forward gear forks have three recesses each: the middle one serves to fix the neutral position, the extreme ones - to fix the engaged gear. Two notches are made in the reverse fork rod: one fixes the intermediate gear in the neutral position, the other - when the reverse gear is engaged.
To fix the rods in the neutral or on position, balls 30 are used, which enter the recesses on the rods and are pressed against them by springs 29 and 33. The retainer, consisting of a ball with a spring, is located in a steel sleeve pressed into the box crankcase on the right side.. Under By the action of the spring, the retainer ball, entering the recess, secures the stem in a certain position. To move the rod when shifting gears, the force necessary to push the ball out of the recess is applied.
The gearshift mechanism is equipped with a lock to prevent the simultaneous engagement of two gears, which can occur during the shift if the lower end of the lever 1, standing at the junction between the two rods, will move them together.
The lock consists of a cracker 27 installed in the hole of the third-fourth gear engagement rod, and two crackers 26 and 28 of large diameter installed in the channel of the rear wall of the crankcase between the rods. The length of each of the crackers 26 and 28 is equal to the corresponding distance between the rods 20, 21 and 23 - plus one notch, and the length of the cracker 27 is equal to the diameter of the rod minus one notch. Thus, the length of three crackers is equal to the distance between the rods 20 and 23 plus one notch.
When the first-second gear engagement rod is moved, the biscuit 26 leaves the recess of this rod, enters the recess of the third-fourth gear engagement rod, and through the biscuit 27 introduces the biscuit 28 into the recess of the reverse engagement rod. Rods 20 and 23 are locked in the neutral position. When moving the reversing rod, rods 20 and 21 are locked.
If the third-fourth gear shifting rod moves, then crackers 26 and 28 come out of its recess, enter the recesses of the rods 21 and 23 and lock them in the neutral position.
To turn on the reverse gear, you must first press the handle 17 down (compressing the spring 10) so that the protrusion 37 of the shift lever goes below the edge of the guide cup 4, and then move the lever handle to the right and back. In the normal position of the lever, due to the emphasis of the protrusion 37 of the lever against the edge of the cup 4, the possibility of accidentally turning on the reverse gear is eliminated.
When the gear lever is moved to the neutral position, the spring 10 raises the lever up. The gear lever 1 has a thickening in the form of a ball head, on which it swings in the spherical part of the stamped support 5. The spring 10, relying on the spherical washer 9 and the support washer, locked on the lever with a ring, presses the lever 1 to the surface of the support and holds it. From turning the lever 1 in the support is held by the guide pin 6, the end of which enters the hole of the ball bearing.
When you turn on the first or second gear, the handle of the rod of the gear lever 1 is moved to the left until the lower end of the lever stops against the limit bolt 24. In this position, the return spring 2 is stretched.
If the gears are not engaged and the handle 17 of the shift lever is released, then the spring 2 pulls the lever to its extreme position until the limiting ledge stops against the guide cup. In this case, the lower end of the lever 1 is in the groove of the head of the third-fourth gear engagement rod.
A rod is put on the upper end of the lever 1, in which a damper is installed, consisting of a rubber thrust pad 16, two rubber bushings 14, a plastic distance sleeve 18 and an elastic plastic locking sleeve 13. The damper eliminates the vibration of the handle and the rod when the car is moving.
From the ingress of dust and dirt into the gearbox, the ball bearing of the shift lever is protected by a rubber boot 11.
The hole for the shift lever to pass into the car interior is sealed from below with a special cuff, which is put on flange 7 and rests against the bottom of the car body.
The scheme of the gearbox. In the neutral position, the lower end of the gearshift lever 1 is pulled by the spring 2 until the restrictive ledge stops in the guide cup and is located in the head of the third-fourth gear engagement rod. The synchronizer clutches and the reverse gear are not engaged with the corresponding gears and the torque is not transmitted to the driven shaft.
In first gear, the first and second gear synchronizer clutch moves back (in the direction of the arrow), engages with a special ring gear of the driven gear of the first gear and connects it to the hub, which is motionless on the driven shaft. In this case, the torque from the input shaft through the gear of constant engagement will be transmitted to the intermediate shaft and through the gears of the first gear of the intermediate and driven shaft to the driven shaft.
In second gear, the same synchronizer clutch moves forward and connects the loose second gear to the output shaft. Torque is transmitted from the input shaft through a pair of constant mesh gears to the intermediate shaft and from it through the gears of the second gear of the intermediate and driven shafts to the driven shaft.
In third gear, the third and fourth gear synchronizer clutch moves back and connects the third gear to the output shaft.
In fourth gear, the synchronizer clutch, moving forward, connects the driven and drive shafts and the torque is transmitted directly from the drive shaft to the driven.
Reverse is achieved by entering the intermediate reverse gear into simultaneous engagement with the reverse gears of the intermediate and driven shafts. Since the intermediate gear is involved in the transmission of torque from the intermediate shaft to the driven, the latter rotates in the opposite direction. To ensure smooth engagement, the ends of the teeth of the reverse gears are rounded.
Engagement of reverse gear should be made only after the vehicle has come to a complete stop.
Smooth and bumpless engagement of forward gears is provided by synchronizers.
The diagram of the synchronizer in position a shows the neutral position of the synchronizer of the third and fourth gears.
When the third gear is engaged, the sliding clutch of the synchronizer moves along the splines of the hub, which is rigidly connected to the driven shaft. Having moved, the clutch with its inner cone is pressed against the outer conical surface of the blocking ring. Friction occurs between the cones, as a result of which the blocking ring turns all the way with its teeth into the ends of the teeth of the synchronizer crown of the third gear driven gear.
Diagram b shows the position of the parts at the beginning of the third gear.
The clutch together with the blocking ring cannot move further in the axial direction until the speeds of rotation of the driven and intermediate shafts are equalized (3rd gear driven gear with locking ring and synchronizer clutch with hub on the driven shaft).
The alignment of the rotation speeds leads to the disappearance of the friction force between the cones of the locking ring and the clutch, and under the action of the axial force of the engagement fork, the locking ring, having slipped off the bevels of the ring gear, will move further along with the clutch, rigidly connecting the driven gear of the third gear with the hub 36 with the splines of the clutch. Thus, the third gear will be included.
The diagram in shows the placement of parts with the third gear engaged. In this position, the synchronizer clutch will disengage from five short, but fuller teeth of the hub 36. On the remaining teeth, the clutch will turn by an amount equal to the difference in the side clearance of the full teeth disengaged and those remaining in engagement, and the beveled ends of the disengaged teeth will rest against the ends of the short teeth of the hub 36. So the clutch is additionally fixed in the on position.
The synchronizer works similarly when other forward gears are engaged. When the gear is turned off, the parts return to the neutral position, and the blocking ring is thrown back by the spring until it stops against the retaining ring.