JPS6140857B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a synchronous meshing device for a gear transmission that synchronizes and meshes spline teeth of a sleeve and spline teeth of a gear.

In general, synchronous meshing devices for gear transmissions include constant load type, inertia lock type key type,
There are various types such as inertia lock type and pin type, but the basic structure is a synchronizer hub fixed on the spline of the main shaft, a sleeve fitted with the spline on the outer circumference of this hub and sliding in the thrust direction, and a gear. The sleeve is slid in the thrust direction by a shift fork that engages with a groove or protrusion on the outer periphery of the sleeve to operate the conical friction clutch portion and perform a synchronizing action. The sleeve is engaged with either a gear that meshes with the counter gear and idles on the main shaft, or a drive gear that is directly connected to the clutch shaft, thereby transmitting the drive torque of the clutch shaft to the main shaft.

The engagement between the sleeve and the gear is often achieved by dog teeth with tapered tips, as shown in FIG. 1, to prevent the gear from coming off. in this case,
Now, 2a is the spline tooth of the synchronizer hub, 3a is the spline tooth of the sleeve 3, and 9b is the dog tooth of the gear, and the state shown in FIG. 1 is achieved by moving the shift fork 4 a certain amount in the direction of arrow A. After the shift is completed, the dog tooth 3b of the sleeve 3
When the dog teeth 9b of the gear and the dog teeth 9b of the gear are in mesh with each other, the force F transmitted from the dog teeth 9b of the gear to the dog teeth 3b of the sleeve 3 is F ₁ due to the inclination of the taper when viewed from the sleeve 3 side. and F ₂
It is decomposed into the power of Due to this _F2 force, the entire sleeve 3 receives a force in the direction of arrow A. Therefore, one side surface 4a of the shift fork 4 that engages with the groove 3c on the outer circumference of the sleeve
As the sleeve 3 rotates while being subjected to a force in the direction of arrow A, it gradually wears out, and as a result, proper shifting cannot be performed.

Therefore, conventionally, as shown in Figs. 2 and 3,
The part of the spline groove of the sleeve 3 in which the dog tooth 9b of the gear 9 engages is formed into a concave shape with a predetermined width and depth to provide a concave step 3d, and the dog tooth 9b of the gear is fitted into this concave step 3d. The synchronizer is formed at a height that allows engagement, and at the end of the shift, the recessed step portion 3d and the dog tooth 9b of the gear are engaged, and the force in the thrust direction applied to the sleeve 3 is prevented, thereby reducing wear on the shift fork 4. A meshing device is provided (Utility Model Publication No. 54-37004).

However, in this case, the depth of the groove 3e between the spline teeth 3a and 3b of the sleeve 3 and the dog tooth 3
Since the depth of the recessed step portion 3d between b and 3b is different,
If an attempt was made to actually form the recessed step portion 3d, the process would be extremely difficult, and there would be a drawback that it would not be suitable for mass production and could not be put to practical use.

The present invention has been made in view of the above-mentioned drawbacks.The purpose of the present invention is to reduce the wear of the shift fork by blocking the force in the thrust direction generated on the sleeve at the end of a shift, and to provide a gear shifting system that is easy to manufacture and highly suitable for mass production. The purpose of the present invention is to provide a synchronous meshing device for a machine.

In order to achieve the above object, the present invention provides a stopper in the tooth groove portion of at least one of the spline internal teeth of the sleeve, and also provides a stopper fitting portion on the outer periphery of the synchronizer hub and synchronizer ring corresponding to the stopper. At the end of the shift, the dog teeth of the gear come into contact with the side surface of the stopper to restrict the movement of the sleeve in the thrust direction.On the other hand, the shape of the stopper is simplified, and the stopper fitting part also has teeth notched. By making the process simple, the process was made easier and mass production possible.

The present invention will be described below with reference to the accompanying drawings.

FIG. 4 shows an inertial lock key synchronizer according to a first embodiment of the present invention. In the figure, 1
2 is a main shaft having the same function as the conventional one; 2 is a synchronizer hub that is spline-fitted and fixed to the main shaft 1 and has spline external teeth 2a and key grooves 2c formed on the outer periphery (see Fig. 5); 3;
4 has spline internal teeth 3a that mesh with the spline external teeth 2a of the synchronizer hub 2 on its inner periphery, and is movable in the thrust direction (see FIGS. 6 and 7); 4 moves the sleeve 3 in the thrust direction; Shift forks 5 and 6 have spline teeth 5a and 6 on the outer periphery that mesh with the spline internal teeth 3a.
A synchronizer ring 7 (see FIG. 8) is inserted into the spline fitting part between the synchronizer hub 2 and the sleeve 3, and has both ends with a certain gap between the engagement grooves 5b and 6b of the synchronizer rings 5 and 6. the synchronizer key engaged
8 has a cone portion 8a that frictionally engages with the cone portion 5c of the synchronizer ring 5, and is a drive gear integrally formed with the input shaft; 9 a cone portion 9a that frictionally engages with the cone portion 6c of the synchronizer ring 6; It is a second gear that idles on the main shaft 1.

As shown in FIG. 6, three stoppers 10 are provided at 120° intervals in the tooth grooves of the spline internal teeth 3a of the sleeve 3.
0 is formed a required distance l (see FIG. 7) inward from the side surface of the sleeve 3, and the height of the stopper 10 is approximately the same as that of the other spline internal teeth 3a. In order to form the stopper 10, it is sufficient to leave three tooth grooves spaced at 120° intervals unformed in the process of machining the spline internal teeth 3a, and to mill the unformed portions to a required depth l.
Note that 10a is a recess formed during the milling process. On the other hand, among the spline external teeth 2a of the synchronizer hub 2 and the spline teeth 5a, 6a of the synchronizer rings 5, 6, three teeth corresponding to the stopper 10 have been removed, and the stopper fitting portions 2b, 5d, 6d is formed. Therefore, the synchronizer hub 2 and the synchronizer rings 5, 6 are spline-fitted to the sleeve 3 and can freely move in the thrust direction.

Next, to explain the operation of the synchronized meshing device of the above embodiment, first, when the sleeve 3 is moved in the direction of arrow A by the shift fork 4, the synchronizer key 7 engaged with the sleeve 3 by the protrusion 7a is direction, and press the synchronizer ring 6 with the end of the key 7 against the cone portion 9a of the second gear 9. At this time, since the width of the engagement groove 6b of the synchronizer ring 6 is slightly larger than the width of the synchronizer key 7, due to the speed difference between the second gear 9 and the synchronizer ring 6,
Synchronizer key 7 is synchronizer ring 6
It rotates in a state closer to one side of the engagement groove 6b.
Therefore, the spline internal teeth 3a of the sleeve 3 and the spline teeth 6a of the synchronizer ring 6 face each other in a different manner.

Further, when the sleeve 3 is pushed in the direction A by the shift fork 4, the synchronizer key 7 is stopped from advancing by the synchronizer ring 6, and the protrusion 7 between the sleeve 3 and the synchronizer key 7 is stopped.
A is disengaged, and only the sleeve 3 moves in the direction A. Then, the spline inner teeth 3a of the sleeve 3 and the spline teeth 6 of the synchronizer ring 6
However, as mentioned above, until the synchronization action is completed, due to the speed difference, the sleeve 3
spline inner teeth 3a and synchronizer ring 6
Since the sleeve 3 is prevented from advancing in the A direction, the cone portion 6c of the synchronizer ring 6 is pressed even more strongly against the cone portion 9a of the second gear 9.

In this way, second gear 9 and sleeve 3
When the rotation speed becomes the same as that of the synchronizer ring 6, the synchronizer ring 6 becomes free in the direction of rotation, allowing the sleeve 3 to enter freely, and the sleeve 3 meshes with the dog teeth 9b of the second gear 9, completing the shift ( (See Figure 9).

At this time, in the present invention, since the tip of the dog tooth 9b of the second gear 9 comes into contact with the side surface of the stopper 10 of the sleeve 3, the thrust force in the A direction generated in the sleeve 3 is blocked, and therefore the shift fork 4
No excessive force is applied to the shift fork 4, and wear on the shift fork 4 can be reduced.

10 and 11 show a second embodiment of the present invention, in which a stopper 10' is fixed to the tooth groove portion of the spline internal teeth 3a of the sleeve 3 by welding or rivets. Since it is only necessary to fix the stopper 10' to the tooth groove of the existing sleeve, the machining becomes easier. The synchronizer hub 2 and synchronizer ring 6 are shown in FIG.
The same one as shown in FIG. 8 may be used.

As is clear from the above description, according to the present invention, the sleeve is provided with a stopper that the dog teeth of the gear come into contact with at the end of the shift, thereby preventing the sleeve from moving in the thrust direction and reducing wear on the shift fork. can do. Moreover, since the stopper and the stopper fitting portion require simple machining, they are easy to manufacture and can be easily mass-produced.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing a conventional synchronized meshing state, Fig. 2 is a partial longitudinal cross-sectional view of a conventional synchronized meshing device that is an improved version of this, and Fig. 3 is a partially exploded view showing the sleeve spline used in this synchronized meshing device. 4 and below show the present invention, FIG. 4 is a partial vertical sectional view of the synchronizer of the first embodiment, FIG. 5 is a front view of the synchronizer hub, FIG. 6 is a front view of the sleeve, Fig. 7 is a partially exploded view showing the splines of this sleeve, Fig. 8 is a front view of the synchronizer ring, Fig. 9 is a partial vertical sectional view of the synchronizer at the end of a shift, and Fig. 10 is a second embodiment. FIG. 11 is a partially exploded view showing the splines of this sleeve. 1... Main shaft, 2... Synchronizer hub, 2a... Spline external teeth, 2b... Stopper fitting portion, 3... Sleeve, 3a... Spline internal teeth, 4... Shift fork, 5, 6... Synchronizer ring, 5a, 6a...spline teeth,
5d, 6d...Stopper fitting portion, 7...Synchronizer key, 8...Drive gear, 9...Second gear, 9b...Dog tooth, 10, 10'...Stopper.

Claims (1)

[Claims] 1. A synchronizer hub that is fixed to the rotating shaft and has spline external teeth formed on its outer periphery, a sleeve that has spline internal teeth formed on its inner periphery and that meshes with the spline external teeth and is movable in the thrust direction, and meshes with the spline internal teeth. In a synchronous meshing device for a gear transmission comprising a synchronizer ring having spline teeth on its outer periphery, and a gear having dog teeth on its outer periphery into which the synchronizer ring is fitted and meshing with the spline inner teeth, the sleeve has spline inner teeth. At least one of the tooth grooves is provided with a stopper projecting inward at a position a predetermined distance inside from the side surface of the sleeve and at approximately the same height as the spline internal teeth, and the spline external teeth of the synchronizer hub corresponding to this stopper are provided. and a synchronizing meshing device for a gear transmission, wherein spline teeth of a synchronizer ring are removed to form a stopper fitting portion, and dog teeth of a gear are configured to abut against a side surface of the stopper at the end of a shift.