JPS5854290B2 - Automotive gear transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automobile gear transmission equipped with a synchronizer.

Generally, when changing gears, the synchronizer of a gear transmission for an automobile
The synchronizing side, which rotates integrally with the output shaft, and the synchronized side, which is rotatably supported by the output shaft and is idling, are brought into frictional engagement to decelerate or increase the speed of the synchronized side, and the synchronized side and the synchronized side are It works to match the rotation speed of the.

The rotational force (torque) applied from the synchronizing side to the synchronized side due to such frictional engagement is not only consumed for increasing and decreasing the inertial mass momentum of the synchronized side, but also for friction of various parts and stirring of lubricating oil.

The torque consumed due to the friction of each part and stirring of the lubricating oil is generally called resistance torque, and is a torque that acts in the direction of attenuating the rotational speed of the synchronized side.

Therefore, especially during downshifts when the synchronized side is rotated in the speed increasing direction, this resistance torque is large (it acts to increase the impulse required for shifting, worsening the ease of operation and the feeling when shifting is small). was.

In view of the fact that a large operating impulse is required when downshifting, the applicant has filed a patent application in Japanese Patent Publication No. 48-95 related to the earlier application.
In No. 28, a friction member that makes elastic frictional contact with the synchronized side gear that achieves the maximum forward gear ratio is fixed to the output shaft, and when shifting, the rotational force of the output shaft is combined with the synchronized side element to reduce the friction. A gear transmission device has already been proposed in which the rotational speed of the synchronized gear is quickly brought into line with that of the synchronized gear by actively applying the rotation speed to the gear on the synchronized side, thereby reducing the operating impulse.

In the case of such a structure, the friction between the friction member and the synchronized gear that achieves the maximum forward gear ratio is such that, as described above, before synchronization is completed, the friction between the friction member and the synchronized gear that achieves the maximum forward speed ratio causes the output shaft to It serves as a synchronizing torque transmitted from the to the synchronized side, contributing to shortening the synchronization time.

However, in the latter half of the shift operation after synchronization is completed, the synchronizer's
- When the bub sleeve meshes with the gear on the synchronized side, the gear on the synchronized side must rotate with respect to the output shaft by the amount of phase shift with the spline part of the bub sleeve, and therefore, at this time, the friction member The friction between the gear and the gear to be synchronized acted as resistance, causing a problem that conversely deteriorated the shift feeling in the latter stages of the shift operation.

In addition, in automobile gear transmissions equipped with synchronizers, the gears are highly processed to prevent noise at high rotation speeds and improve durability, but the assembly of the gears is difficult. An arbitrary backlash is set when

Therefore, when the transmission is in neutral and the engine is in an idling state, large rotational fluctuations due to periodic explosions of the engine repeatedly impact the meshing parts of the gears, causing the gears to wobble, causing so-called looseness. There was a problem in that it produced a banging sound.

In view of the above-mentioned various malfunctions and problems in conventional gear transmissions for automobiles with synchronizers, the present invention has been developed to solve the following problems: It is an object of the present invention to provide an improved gear transmission for an automobile that improves the feeling and also prevents the rattling sound of the gears.

According to the present invention, in an automobile gear transmission equipped with a synchronizing device, it is possible to make elastic frictional contact with a synchronized gear that is rotatably supported on an output shaft and that achieves a maximum forward speed ratio. by a gear transmission for an automobile, such as a friction member having a friction member that is connected to the output shaft in such a manner that the friction member can rotate relative to the output shaft by at least an angle of rotation required for meshing of the synchronizer. achieved.

In such a configuration, when shifting while driving,
Similar to the above-mentioned Japanese Patent Publication No. 48-9528, the gear on the synchronized side receives the rotational force of the output shaft from the synchronized element as well as the friction torque from the friction member, and that friction torque is applied to the gear on the synchronized side. Since the resistance torque acting on the gear due to oil agitation etc. is canceled out and the gear to be synchronized is actively accelerated, synchronization becomes easier and shift operation force is reduced.

Further, when the structure of the present invention is used, the friction member is configured to be able to rotate with respect to the output shaft by at least the rotation angle required for meshing of the synchronizer, so that the maximum forward speed change on which the friction member is acting is When shifting to the synchronized gear to achieve the ratio, the friction between the synchronized gear and the friction member causes the rotational displacement of the synchronized gear with respect to the output shaft when the synchronizer and the synchronized gear mesh with each other. The shift feeling to the gear to be synchronized is improved.

Further, when the transmission is located in neutral and the engine is in an idling state, friction torque generated via a friction member between the synchronized side gear that achieves the maximum forward gear ratio and the output shaft This acts as a resistance torque on the driven gear train made up of the side gear, the counter gear meshed with the side gear, and other synchronized side gears, thereby avoiding the occurrence of rattling noise of the gears.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a half-sectional view showing the essential parts of one embodiment of the present invention in an automobile gear transmission equipped with a typical Borgwarner synchromesh mechanism among inertia lock synchronizers. 2 is a view taken along arrow A in FIG. 1.

In the figure, 1 is an output shaft of a gear transmission, and this output shaft 1 rotatably supports a first gear 4 via a needle roller bearing 3 on the outer periphery of a sleeve 2 which is key-coupled to the shaft. At the same time, a second gear 5 and a third gear 6 are individually rotatably supported at positions a predetermined distance apart from the first gear 4 in the axial direction.

In this case, the first gear 4 is the so-called first (low) gear that achieves the maximum forward gear ratio, the second gear 5 is the second gear, and the third gear 6 is the third gear. Although not shown in the figure, the counter gears are always in mesh with each other, so that the rotational force of the engine is transmitted.

A synchromesh mechanism 7 is installed between the first gear 4 and the second gear 5 to selectively drive and connect one of them to the output shaft 1.

(In addition to the three gears mentioned above, the output shaft 1 integrally includes a fourth gear, which is generally called a top gear, although it is not shown in the figure. A synchromesh mechanism is also incorporated between the third gear 6, but since it is constructed in exactly the same way as the synchromesh mechanism 7 provided between the first and second gears, Illustrations and explanations are omitted.

) The synchromesh mechanism 7 includes a clutch bub 8 spline-coupled to the output shaft 1 between the first and second gears 4 and 5 and having a spline formed on the outer periphery; Friction occurs between spline rings 11 and 12 which are integrally attached to each of the gears 4 and 5 and have splines 9 and a conical outer circumferential surface 10 on the outer periphery, and the conical outer circumferential surfaces of these spline rings 11 and 12. Synchronizer ring 1 that engages and has splines 13 on its outer peripheral surface
4 and 15 are spline-coupled to the outer periphery of the clutch bub 8 by a spline 16 formed on the inner periphery so as to be movable in the axial direction, and a shift fork (not shown in the drawings) is fitted to the outer periphery. Groove 17 and reverse gear 18
The shifting key 21 is fitted into a groove 20 formed on the outer periphery of the clutch hub 8 so as to be movable in the axial direction. The key 21 is pressed against the inner surface of the bub sleeve 19 by the spring force of two ring-shaped key springs 22, and when the bub sleeve 19 is in the neutral position, the protrusion provided in the center part is pushed inside the knob sleeve 19. The shifting key 2 is adapted to fit into a groove provided in the center of the peripheral surface, and the shifting key 2
Both ends of the synchronizer ring 14,
It fits into a notch groove 23 provided in 15.

Therefore, when the output shaft 1 rotates, the clutch bub 8, bub sleeve 19, and shifting key 2 are rotated.
1 and two synchronizer rings 14 and 15 rotate in the same manner.

The spline 16 provided on the inner peripheral surface of the bub sleeve 19 can mesh with the spline 13 of the synchronizer ring 14-15 and the spline 9 of the spline ring 11-120. Spline 1 of synchronizer rings 14 and 15
3 and the spline rings 11, 120.One end of the spline 9 is chamfered to achieve a smooth spline connection, making it a so-called chamfer.

Note that the notch groove 23 has the spline 16 connected to the spline 1.
The notch grooves are formed to be larger than the shifting key 21 by a predetermined amount so that the synchronizer rings 14 and 15 can rotate relative to the shifting key 21 by the rotation angle necessary to engage the synchronizer rings 3 and 9.

(See Figure 3) The above is the structure of a normal gear transmission equipped with a Borgwana synchromesh mechanism, but in the case of the present invention, the synchronized side gear that achieves the maximum forward gear ratio, i.e. A ring-shaped friction member 25 is in sliding contact with a conical outer circumferential surface 24 of a recess provided on the right side surface of the first gear 4 .

The friction member 25 has a notch groove 26 on the right edge in the figure, and a linking pin 27 to which a flange portion of the sleeve 2 integral with the output shaft 1 is attached is attached to the notch groove 26. engaged.

As clearly shown in FIG. 2, the notch groove 26 is formed so that the friction member 25 is connected to the connecting pin by the rotation angle necessary for the spline 16 of the buff sleeve 19 to engage with the spline of the synchronizer ring 14 and the spline 9 of the spline ring 11. 27, in other words, it is formed into a notched groove having a dimension larger in the circumferential direction by a predetermined amount than the diameter of the linking pin 27 so as to be able to rotate with respect to the output shaft 1.

The friction member 25 is flexibly pressed to the left in the figure by a compression coil spring 28 elastically mounted between the linking pin 27, and its inner circumferential surface is pressed against the conical outer circumferential surface by a diametrical component of the spring 28. 24.

In this configuration, the operation when downshifting from second speed to second speed will be explained.

When traveling in second gear, the bub sleeve 19 is moved to the left from the state shown in the figure, and the spline 16 is connected to the spline 13 of the synchronizer ring 15 and the spline 9 of the spline ring 12 integrated with the second gear 5. They mesh together.

At this time, the rotational force of the engine is transmitted to the output shaft 1 via the second gear 5, the spline ring 12, the knob sleeve 19, and the clutch bub 8.

When the bub sleeve 19, which is engaged with the splines 9 of the spline ring 12 and the splines 13 of the synchronizer ring 15, is moved to the right in the figure for downshifting, a neutral state is temporarily established as shown in the figure.

During such a shift, a clutch (not shown here) is activated to cut off the transmission of engine power to the transmission, but the vehicle continues to run due to inertia, and rotational force is transmitted from the wheels to the output shaft 1 of the transmission. Therefore, the output shaft 1 maintains almost the same rotation as when running in second speed.

On the other hand, the first and second gears 4, 5, etc. try to decelerate relatively rapidly due to the resistance torque as described above, but in the case of the present invention, the friction member rotating together with the output shaft 1 Since the rotational force is transmitted to the first gear 4 through the frictional engagement between the first gear 25 and the first gear 4, the rotational force is transmitted to the first gear 4 through the first gear 4 and a counter gear not shown in the figure. The rotational speeds of the other gears 5 and 60 do not drop suddenly despite the resistance torque.

In order to achieve the first speed mesh in such a state, when the bushing sleeve 19 is further moved toward the first gear 4, the shifting key 21 is moved together with the bushing sleeve 19 to the right side in the figure. The synchronizer ring 14 is moved to press the synchronizer ring 14 against the conical outer peripheral surface 10 of the spline ring 11 at its end.

Thereby, the synchronizer ring 14 frictionally engages with the spline ring 11 integrated with the first gear 4, and synchronizes 40 rotations of the first gear with 10 rotations of the output shaft.

At this time, as described above, the second gear 4 receives the rotational force from the friction member 25 on its conical outer peripheral surface 24, so the difference in rotational speed with the output shaft 1 is small, and synchronization is completed in a short time. ,
The impulse required to move the buffing sleeve 19 to the right side for synchronization can also be small.

When the buff sleeve 19 is further moved to the right, the shifting key 21 cannot be moved to the right any further, so the protrusion separates from the groove of the bub sleeve, and the bub sleeve 19 overcomes the spring force of the key spring 22. move further to the right while pressing the shifting key 21.

In this case, before the shifting key is completely sunk, the splines 16 of the bub sleeve 19 and the splines 13 of the synchronizer ring 14, which were facing each other while maintaining appropriate relative positions, are separated from each other as shown in FIG.
The surfaces contact each other, and the synchronizer ring 14 is further strongly pressed against the conical outer circumferential surface 10 of the spline ring 11.

At this time, if synchronization has not yet been completed, the speed of the first gear 4 continues to increase as the frictional force increases.

After the synchronization is completed, the splines 16 of the bub sleeve 19 and the splines 13 of the synchronizer ring 14 are engaged with each other at their chamfered surfaces, as described above, and this state is shown in FIG.

In FIG. 3, the rotation direction of the bub sleeve 190 is the direction of arrow R, and the shifting direction is the direction of arrow C.

In order to further deviate the buff sleeve 19 to the right from this state and cause its splines 19 to engage with the splines 13 of the synchronizer ring 14 and the splines 9 of the spline ring 11, the synchronizer ring 14 and spline ring 11 must be moved to the bub sleeve 19. On the other hand, it is necessary to shift it toward the advancing side in the rotational direction.

At this time, if the friction member 25 is integrally attached to the output shaft 1, the first gear 4 must also be deviated relative to the friction member 25, and the friction between them will be reduced during the shift operation. However, according to the present invention, due to the engagement between the notch groove 26 and the linking pin 27, the friction member 25 rotates only the rotation angle necessary for the engagement of the synchronizer with respect to the output shaft 1. Since it can rotate about the output shaft,
At this time, there is no need to make a relative deviation between the first gear 4 and the friction member 25, and the first gear 4 is connected to the friction member 25.
5 and is offset with respect to the output shaft, so that the operating feeling of the first gear 4 is not impaired when shifting to the first gear 4.

Furthermore, when the transmission is in the neutral position and rotation is not transmitted to the output shaft 1 and the first gear 4 etc. are idling, the braking force due to the frictional engagement between the friction member 25 and the first gear 4 is generated. A large resistance torque acts on the first gear 4, a counter gear (not shown in the figure), and second and third gears 5, 6 which are connected via this counter gear, resulting in the meshing of each gear. This prevents the gear from rattling even if a shock due to rotational fluctuation is applied to the outer part.

Therefore, generation of rattling noise during idling is avoided.

4 to 7 show other embodiments of the transmission gear device according to the present invention.

In FIGS. 4 to 7, parts corresponding to FIGS. 1 to 3 are designated by the same reference numerals as those in FIGS. 1 to 3.

In the case of the second embodiment shown in FIGS. 4 and 5, the friction member is an oil which is fitted with a predetermined tension on the straight outer peripheral surface 24' provided on the first gear 4. It consists of a rubber spring element 25a such as a seal and a metal outer frame 25b that is integrally fitted to the outer peripheral surface of the element.
A cutout groove 26 is provided in the outer frame 25b, with which the linking pin 27 engages.

In this case, substantially only a radial force acts on the first gear 4 from the friction member.

In the embodiment shown in FIGS. 6 and 7, the friction member 25' is tightened radially inwardly by a ring-shaped spring 28' mounted around the outer periphery of the friction member 25'. Frictional force is generated between the gear 4 and the gear 4.

In this case, if the output shaft 1 rotates at high speed, the friction member 25
Centrifugal force acts outward at ', the frictional force with the first gear 4 is reduced, the wear of the friction surfaces of both gears is reduced, and the friction loss that occurs during running can also be reduced.

Although the present invention has been described above with reference to specific embodiments, the present invention is not limited to these embodiments, and various embodiments and modifications can be made within the scope of the present invention. will be clear to those skilled in the art.

[Brief explanation of drawings]

FIG. 1 is a half-sectional view of the present invention applied to an automobile gear transmission equipped with a Borgwarner synchromesh mechanism, which is a typical example of an inertia lock synchronizer.
FIG. 2 is a view taken in the direction of arrow A in FIG. 1, FIG. 3 is a partial schematic explanatory diagram of a spline meshing part, and FIG. 4 is a half of the main part showing another embodiment of the gear transmission according to the present invention. 5 is a view in the direction of arrow A in FIG. 4, FIG. 6 is a half sectional view of a main part showing still another embodiment of the present invention, and FIG. 7 is a view taken along the line in FIG. 6. It is a sectional view along ■-■. 1 - Output shaft, 2 - Sleeve, 3 - Needle roller bearing, 4 - First gear, 5 - Second gear, 6 - Third gear, 7 - Synchromesh mechanism, 8 - Clutch hub, 9
~ Spline, 10 ~ Conical outer peripheral surface, 11.12 ~ Spline ring, 13 ~ Spline, 14, 15 ~ Synchronizer link, 16 ~ Spline, 17 ~ Groove, 18 ~
Reverse gear, 19 - hub sleeve, 20 - groove, 21 - shifting key, 22 - key spring, 23 - notch groove, 24 - conical outer peripheral surface, 25 - friction member, 26 - notch groove, 27 - Linking pin, 28~compression coil spring.

Claims (1)

[Claims] 1. In an automobile gear transmission equipped with a synchronizer,
A friction member is rotatably supported on the output shaft and makes elastic frictional contact with the synchronized side gear that achieves the maximum forward speed ratio, and the friction member is rotated by at least the rotation angle necessary for meshing the synchronizer. A gear transmission for an automobile, characterized in that the gear transmission is connected to an output shaft in a manner that it can rotate relative to the output shaft.