JPH0242216A - Mechanism for preventing reverse gear in transmission from rumbling - Google Patents

Abstract

PURPOSE:To enable smooth gear shift so as to prevent a reverse gear in a transmission from rumbling, by providing a reverse cone which is engaged with a forward stage synchronous cone and is frictionally engaged with a reverse conical friction surface. CONSTITUTION:Spline teeth 5a on a clutch hub 5 is always meshed with a spline teeth 6a on a sleeve 6. A conical outer peripheral surface 15B of the forward stage synchronous cone 15 is frictionally engaged with a forward stage conical friction surface 7A of a cyclic ring 7. A conical outer peripheral surface 16B of a reverse synchronous cone 16 is frictionally engaged with a reverse conical friction surface 7B of the cyclic ring 7. With this arrangement, it is possible to smoothly shift gears and to prevent a reverse gear in the transmission from rumbling.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a mechanism for preventing reverse gear noise in a gear transmission equipped with a synchronizing device in a vehicle or the like.

[Conventional technology]

Generally, in a gear transmission of a vehicle, when the vehicle is moved backward, the meshing device is put into the reverse gear and reverse rotation is transmitted to the transmission output shaft.
Similar to a general forward meshing mechanism, the reverse gear, which continues to rotate inertia, first meshes with the sleeve that slides in the axial direction in response to the operation of the gear shift control lever, and then engages with the reverse gear in a conical shape. Mainly used are either a synchronizing device equipped with a synchronizing ring that engages with a friction clutch on the friction surface of the synchronizing device, or a direct meshing method of gears that does not have such a synchronizing device at all.

These mechanisms will be explained with reference to the drawings.

First, the format of the former synchronizing device is shown in FIG.

In FIG. 7, reference numeral 1 indicates the output shaft, and this output shaft 1
On the input side, a reverse gear 2 and a forward gear (for example, a fifth forward gear) gear 3 are loosely fitted through bearings. The reverse gear 2 is meshed in the opposite rotational direction to a human-powered shaft arranged parallel to the output shaft 1, and the forward gear 3 is meshed and connected in rotational order to the input shaft, and both gears are connected to the main clutch. As long as the output shaft 1 is rotated in reverse or sequential order, the output shaft 1 rotates in reverse or sequential order. A clutch hub 5 of a synchronizer 4 is fixed between the gears 2 and 3 of the output shaft, and the clutch hub 5 has a large number of spline teeth all around its outer circumferential surface. A suitable number (preferably three) of key grooves for accommodating insert keys 27 are formed at equal intervals. The insert key 27 is configured to be able to slide in the keyway in the axial direction of the clutch hub 5, and is always urged against the inner circumferential surface of the sleeve 6 by a ring-shaped spring 28. The sleeve 6 is slidably supported on the clutch hub 5 via an insert key 27, and has spline teeth 6A on its inner circumference, and a shift fork that interlocks with a gear shift lever (not shown) on its outer circumference. A circumferential direction 1116F is formed. Reverse gear 2
A reverse spline member 8 is fixed to the side of the synchronizer 4 in a relatively non-rotatable manner, and a conical surface 8B is formed at the right end in the figure, which is the conical surface of the reverse synchronizer ring 10 disposed between the clutch hub 5. 10B and is configured to be able to engage with the clutch. Further, spline teeth 10A are formed on the outer peripheral surface of the reverse synchronization ring 10, and spline teeth 8A are formed on the outer peripheral surface of the reverse spline member 8 at the same time. In the opposite portion of the reverse synchronization ring 10 to the insert key 27, grooves 10C are formed at equal intervals around the outer circumference, into which one end leg of the insert key 27 is loosely inserted and fitted.

Similarly to the reverse gear 2 side, the forward gear 3 is also provided with a forward gear spline member 9 and a forward gear synchronization ring 19, with spline teeth 9A, 19A.

The conical surfaces 9B, 19B and the groove 19C have a similar structure and are arranged symmetrically with respect to the synchronizer 4.

In this synchronizer 4, when the sleeve 6 is shifted to the right side in FIG. 7 by operating the gear shift operation lever after disengaging the main clutch, the output shaft 1 rotates in the forward direction by the shift operation in the forward gear, and the output shaft 1 rotates in the forward direction. When shifting to the left in Figure 7, the vehicle is moving backwards and the output shaft 1 normally stops rotating.
In either case, as the sleeve 6 moves, the insert key 27 also moves in the same direction, and its tip leg advances within the groove 10C of the reverse synchronization ring 10 or the groove 19C of the forward synchronization ring 19. , impinging on the axial end faces of these grooves and further displacing the synchronizing ring 10 or 19 axially to the left or to the right on the spline member 8.9. This speed change operation causes the inner conical surface 10B of the synchronizing ring 10.19 to
or 19B is the outer conical surface 8B of the spline member 8.9
or 9B, synchronization is performed between the spline member 8.9, that is, the reverse gear 2 or the forward gear 3, and the spline teeth 6A of the sleeve 6 are connected to the synchronization ring 10 or 1.
The spline teeth 10A and 19A of the spline members 8 and 9 are then engaged with the spline teeth 8A and 9A of the spline members 8 and 9, thereby completing the speed change operation. When shifting to reverse, even if the main clutch is disengaged and the input shaft is separated from the engine, the reverse gear 2 is still rotating due to the inertial rotation of the input shaft system. A brake will be applied to the rotation of the reverse gear. Transmissions incorporating a synchronizing device using such a synchronizing ring are disclosed, for example, in Japanese Utility Model Application Publication No. 52-98054, Japanese Utility Model Application Publication No. 58-118319, and the like.

Next, the latter direct engagement mechanism is shown in FIG. 8, and the same reference numerals as those shown in FIG. 7 above indicate similar members. A detailed explanation will be omitted here. Although the spline member 18 of the reverse gear 2 has spline teeth 18A on its outer periphery, it does not have a conical surface on the clutch hub 5 side, nor does it have a reverse synchronization ring that frictionally engages with this conical surface. Therefore, when the sleeve 6 is shifted to the left side in the figure by operating the speed change operation lever when the vehicle is traveling backwards, the inner peripheral spline teeth 6A of the sleeve 6 directly mesh with the spline teeth 18A of the reverse spline member 18. In addition, in this type, in order to prevent the insert key 27 from falling down, the insert key 27 is used to ensure support when it falls down.
A special insert key must be used in which one leg 27A is longer than the other leg to ensure strength against the increased load on the leg 27A. This is also a factor that increases the manufacturing cost of transmissions.

[Problem to be solved by the invention]

However, with the former type of synchronizer, the operation during gear shifting is smooth without the occurrence of shocks or abnormal noises caused by tooth collisions, but on the other hand, it has many components and does not have a synchronizing mechanism. When installing a new synchronizing mechanism in a machine, a conical friction surface, that is, a synchronizing cone, and a synchronizing ring must be stored between the reverse gear and the clutch hub, but there is no space to install them, making it impossible to install them. There are many things. In addition, if this type of synchronization mechanism is designed in the same way as the synchronization mechanism for forward gear, synchronization will be established even if a malfunction such as shifting to reverse gear occurs while the vehicle is moving forward, which is extremely dangerous. be. Furthermore, in order to obtain design values that prevent synchronized meshing during forward movement as described above, many experiments are required, resulting in a lot of wasted time and cost.

In addition, the latter direct mesh type has no synchronizer at all, so the meshing of the reverse gear when shifting to reverse will depend on the meshing of the reverse gear while the engine is running.
When a shift operation is performed to the reverse gear while the vehicle is running or the gear is rotating due to inertia, the spline teeth formed on the inner circumferential surface of the sleeve and the dog teeth of the reverse gear, that is, the spline teeth, will violently contact each other, causing shock and gear damage. There is a problem that noise occurs. Therefore, there is a problem of how to configure a transmission so that it can shift to reverse gear without malfunction and prevent shock and gear noise.

The purpose of this invention is to solve the above problems, and by using a reverse synchro cone that meshes with the synchro cone of the adjacent gear and rotates at the same time, the structure is simple and has a small number of parts, resulting in a smooth structure. By providing a reverse gear noise prevention mechanism for a transmission that enables easy gear shifting operation, can be incorporated into a minimum space, achieves safe and easy-to-engage synchronized operation, and prevents reverse gear noise. be.

[Means to solve the problem]

In order to solve the above problems and achieve the above objects, the present invention is configured as follows.

That is, this invention has dog teeth on both ends of the outer periphery that mesh with spline teeth of a sleeve that fits into the clutch hub, and has conical friction surfaces for forward gear and reverse gear on the inner circumferential surface, and adjacent portions have a reduced diameter shape. a synchronizing ring integrally formed with the forward gear synchro cone that is frictionally engaged with the forward gear conical friction surface; and a reverse synchronizer that is engaged with the forward gear synchro cone and frictionally engaged with the reverse conical friction surface. The present invention relates to a mechanism for preventing reverse gear noise in a transmission, characterized by comprising a cone.

Further, in this invention, the spline teeth of the sleeve that mesh with the reverse dog teeth of the synchronization ring are separated in the longitudinal direction,
It is characterized in that one of the dog teeth of the synchronization ring is disposed in the separation portion.

[Effect]

The reverse gear noise prevention mechanism of the transmission according to this invention is as follows:
Since it is configured as described above, it works as follows. That is, when the synchronizer sleeve and the synchronizer ring having dog teeth on the outer periphery of the synchronizer that are fitted together with the shift of the shift lever slide on the clutch hub, the synchronizer ring slides on the clutch hub. The reverse conical friction surface formed on the synchronization ring is frictionally engaged with the reverse synchro cone that rotates together with the forward stage synchro cone. Therefore, when the sleeve is shifted to the reverse side, it is always synchronized with the adjacent forward gear synchro cone, and after the forward gear and the clutch hub are synchronized, the sleeve can be moved to the reverse side. That is, in order to shift to the reverse side and obtain meshing between the reverse gear and the sleeve, the reverse gear and the sleeve must be synchronized. In other words, in the reverse gear noise prevention mechanism of the transmission according to the present invention, in order to obtain synchronization between the reverse gear and the sleeve, the reverse gear and the forward gear (here, the 5th gear) must be synchronized. By the way, normally in automobile transmissions,
The reverse gear has one more gear in its drive system than the forward gear, and rotates in the opposite direction to the forward gear. Therefore, the reverse gear and the forward gear are synchronized only when the gearbox is stationary, in other words, when the vehicle is stopped and the clutch is disengaged. Therefore, the reverse gear noise prevention mechanism of the transmission according to the present invention performs synchronization only when the vehicle is stopped, and even if the sleeve and the forward gear are synchronized during forward movement, the reverse gear and the sleeve do not mesh with each other. is not obtained,
An erroneous operation such as shifting to the reverse gear does not occur, which is extremely desirable in terms of safety, and since the gears engage in a stopped state, gear noise due to gear engagement can be prevented.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a reverse gear noise prevention mechanism for a transmission according to the present invention will be described with reference to the drawings.

FIG. 1, FIG. 2, and FIG. 3 show an embodiment of a reverse gear noise prevention mechanism for a transmission according to the present invention. FIG. 1 is a sectional view showing a reverse gear noise prevention mechanism for a transmission according to the present invention, FIG. 2 is an exploded view of FIG. 1, and FIG. 3 is an exploded view of FIG. 1. Note that the same reference numerals are given to parts having the same functions as those shown in Figs. 7 and 8. In Fig. 1, the driving force from the output shaft 1 is A synchronizer 14 is shown for smoothly transmitting power to the reverse gear 2 or the forward gear 3, which is the fifth forward gear. This synchronizer 14 includes a forward gear spline member 9 that is integral with the forward gear 3, and a forward gear synchro cone 15 that is integrally constructed with the forward gear spline member 9.
, output shaft! a clutch hub 5 that rotates integrally with the clutch hub 5, a sleeve 6 spline-fitted to the clutch hub 5, a synchronization ring 7 that rotates integrally with the clutch hub 5, a plurality (three) of index springs 12, and a forward stage synchro cone 15. It is composed of a reverse synchro cone 16 that rotates together with the reverse synchro cone 16. A reverse spline member 18 equipped with reverse dog teeth integrally connected to the reverse gear 2 on the side of the synchronizer 14 of the reverse gear 2 is the same as that shown with the same reference numerals in FIG. 8, and its right end surface is aligned with the rotation axis. It has a flat end surface 18B that is perpendicular to the axis (same as the axis of the output shaft l). Spline tooth 1 which is a reverse dog tooth on the outer periphery
8A meshes with the spline @6A of the sleeve 6.

The reverse gear noise prevention mechanism of the transmission according to this invention is as follows:
In particular, it has the following features.

That is, the synchronizer 14 equipped with a reverse gear noise prevention mechanism of this transmission includes a synchronizing ring 7 disposed between a reverse spline member 18 and a clutch hub 5, and a forward gear synchronizer integrally constructed with a forward gear spline member 9. The synchronizing mechanism includes a cone 15 and a reverse synchro cone 16 that rotates integrally with the forward synchro cone 15.

First, in the reverse gear noise prevention mechanism of this transmission, the spline teeth 5A of the clutch hub 5 are always engaged with the spline teeth 6A of the sleeve 6.
A plurality of (three in the figure) notches J5B are formed in the notch. The spline teeth 6A of the sleeve 6 are provided with chamfer portions 6B and 6C at both ends. The synchronizing ring 7 has an integral structure with a plurality of (three in the figure) synchronizing ring arm portions 17 that extend toward the reverse side, and the synchronizing ring arm portions 17 fit into the notched grooves 5B of the clutch hub 5. ing. The synchronization ring 7 has an integral structure with a large number of forward gear dog teeth II on the outer periphery of the forward gear side, and reverse dog teeth 13 on the reverse side end of the synchronization ring arm 17 provided on the synchronization ring 7. have. Further, an index spring 12 is fitted into a recess 17A formed on the outer peripheral side of the synchronizing ring arm portion 17, and the index spring 12 is inserted into the inner peripheral surface of the sleeve 6 and the synchronizing ring arm portion I7.
The sleeve 6 functions to index the forward gear side or the reverse side of the sleeve 6. On the inner circumferential surface of the synchronizing ring 7, a conical friction surface 7A for forward gear on the forward gear side and a conical friction surface 7B for reverse gear on the perspective side are integrally formed in adjacent portions in a reduced diameter shape. Furthermore, a plurality of cutout grooves 15A are formed on the reverse side of the forward stage synchro cone 15, which is integrally constructed with the forward stage spline member 9 that rotates integrally with the forward stage gear 3.

Further, a reverse synchro cone 16 disposed adjacently between the clutch hub 5 and the forward stage synchro cone 15 has a protrusion +6A extending radially inward on its inner peripheral surface. These protrusions 16Δ are respectively engaged or fitted into the notched grooves 15A of the forward stage synchro cone 15, so that the reverse synchro cone 16 and the forward stage synchro cone 15 are configured to rotate together. The conical outer peripheral surface 15B of the forward stage synchro cone 15 is configured to be able to frictionally engage with the forward stage conical friction surface 7A of the synchronizing ring 7, and the conical outer peripheral surface 16B of the reverse synchro cone 16 is configured to be able to frictionally engage with the forward stage conical friction surface 7A of the synchronizing ring 7. It is configured so that it can be frictionally engaged with the reverse conical friction surface 7B.

The reverse gear noise prevention mechanism of the transmission according to this invention is as follows:
It is configured as described above and operates as follows. When shifting to the reverse gear 2, the shift lever is shifted and the sleeve 6 is moved to the reverse spline member 18 side of the reverse gear 2. In this case, the annular n6D inclined surface 6E formed on the inner peripheral surface of the sleeve 6 comes into contact with the index spring 12, and the index of the index spring 12 causes the spline teeth of the sleeve 6 to
The chamfer portion 6B of A engages with the chamfer portion of the reverse dog tooth 13 of the synchronization ring 7, and the synchronization ring 7 is moved to the reverse side together with the sleeve 6. Next, when the sleeve 6 is further moved to the reverse side, the synchronizing ring 7
The reverse conical friction surface 7B formed on the inner circumferential surface of the reverse synchro cone 16 frictionally engages with the reverse synchro cone 16, thereby causing the reverse synchro cone 16 to move forward to the forward stage synchro cone 15.
, the synchronizing ring 7 and the sleeve 6 are forced to be structurally synchronized with the forward spline member 9 or the forward gear 3. By the way, the reverse gear 2 and the forward gear 3 rotate in opposite directions when the vehicle is running or when the clutch is engaged and the output shaft 1 is rotating.
The sleeve 6, which is synchronized with the forward gear 3, cannot mesh with the spline teeth 18A of the reverse spline member 18, which rotates integrally with the reverse gear 2. In other words, when the sleeve 6 moves to the reverse side, the sleeve 6 always synchronizes with the forward gear 3, so the state in which the sleeve 6 can mesh with the spline teeth 1.8A of the reverse spline member 1B is when the sleeve 6 is in synchronization with the forward gear 3. This occurs only when the rotation of the forward gear 2 and the forward gear 3 is stopped, the output shaft is stopped, and the clutch hub 5 is stopped. Moreover,
The forward gear 3 is a 5th gear and has a small inertial mass, so that a shift operation can be performed with a small force.

Therefore, even if they are rotating due to inertia, the reverse gear 2 and the forward gear 3 are brought to a halt due to the synchronization action, and the spline teeth 6A of the sleeve 6 mesh with the dog teeth 18A of the reverse spline member 18. ,
No gear noise occurs at all. In addition, in the case of shifting to the adjacent forward gear 3, which is the 5th gear, the synchronization ring 7
is moved by the sleeve 6, and the shift to the adjacent forward gear 3 is completed by a normal shift action, so a description thereof will be omitted here.

Next, another embodiment of the reverse gear noise prevention mechanism for a transmission according to the present invention will be described with reference to FIGS. 4, 5, and 6. FIG. 4 is a sectional view showing a reverse gear noise prevention mechanism for a transmission according to the present invention, FIG. 5 is an exploded view of FIG. 4, and FIG. 6 is an exploded view of FIG. 4. This embodiment differs from the shape of the synchronizing ring 7 in the above embodiment and some of the spline teeth (two spline teeth formed on the inner circumferential surface of the sleeve 6).
Since they have exactly the same configuration except for the different shapes of the spline teeth (spline teeth), the same parts are given the same reference numerals, and a description of their configuration and operation will be omitted. Regarding the synchronizer 26 of the reverse gear noise prevention mechanism of the transmission of this embodiment, the reverse dog tooth 1 of the synchronization ring 20 is
The spline teeth on a part of the sleeve 6 (three places on the second side) that mesh with the sleeve 6 are separated in the longitudinal direction into spline teeth 21A and 21B, and the separated part 2 between the spline teeth 21A and 21B
2, reverse dog teeth 13 of the synchronizing ring 20 are arranged. The spline tooth 21B has a chamfer portion 21C that engages with the reverse dog tooth 13 of the synchronization ring 20. Further, the forward gear conical friction surface 2OA and the reverse conical friction surface 20B, which are integrally formed adjacent to the inner circumferential surface of the synchronization ring 20, are formed to have rough surfaces, so that a frictional force is generated during frictional engagement. is configured so that it becomes large. Furthermore, an index spring 23 is disposed between the sleeve 6 and the synchronization ring 20 and is configured to perform an indexing function for the axial movement of the sleeve 6. The index spring 23 is attached to the synchronization ring 20 by having its end piece 25 engaged with a retaining hole 24 formed in the outer circumferential surface of the synchronization ring 20.

〔Effect of the invention〕

The reverse gear noise prevention mechanism of the transmission according to this invention is as follows:
The configuration as described above has the following unique effects. Generally, when the transmission is in the neutral position and the output shaft rotation speed is zero, that is, when the vehicle is stopped, the main clutch is turned off, or even if it is already turned off, it is located on the main clutch side. The reverse gear system or rotary shaft system as a rotating system may continue to rotate due to inertia, but if the shift control lever is shifted to the reverse side in such a situation, the spline teeth will collide with each other, causing gear noise. Or, in the worst case, the spline teeth may be damaged. However, the reverse gear noise prevention mechanism of the transmission according to this invention has dog teeth on both ends of the outer periphery that mesh with the spline teeth of the sleeve that fits into the clutch hub. a synchronizing ring having a forward gear conical friction surface and a reverse conical friction surface integrally adjacent to each other on an inner circumferential surface thereof; and a forward gear synchro cone that is frictionally engaged with the forward gear conical friction surface; Reverse circumference! It consists of a reverse synchro cone that frictionally engages with the I friction surface, so as the shift lever shifts, the sleeve of the synchronizer that fits into this and the synchronizer ring that has dog teeth on both ends of the outer periphery slide on the clutch hub. In this case, as the cough synchronization ring moves, the reverse conical friction surface formed on the synchronization ring frictionally engages with the reverse synchro cone that rotates together with the forward stage synchro cone, and the adjacent After synchronizing with the forward gear synchro cone and synchronizing the forward gear and the clutch hub, the sleeve can move to the reverse side. Incidentally, the reverse gear and the forward gear are synchronized only when the transmission is in a neutral position and the rotation speed of the output shaft is zero, in other words, when the vehicle is stopped and the clutch is disengaged. That is, the rotation of the reverse gear and the forward gear is stopped and becomes static, and the spline teeth of the sleeve directly mesh with the dog tooth portion or spline teeth of the reverse gear;
The shift operation to the reverse side is completed. Therefore, an erroneous operation such as shifting to a reverse gear does not occur during forward movement, which is extremely desirable from a safety standpoint, and since both gears mesh in a stopped state, gear noise due to gear meshing can be prevented. Moreover, since the reverse synchro cone is engaged with the forward stage synchro cone and rotates at the same time, each conical friction surface of the synchronizer ring is always brought into frictional engagement with one of the two synchro cones due to the movement of the synchronizer ring. Together, the synchronizing ring and the sleeve can be synchronized, so that the reverse gear and the forward gear are always in a stopped state in the synchronizing action to the reverse side.

In addition, the reverse gear noise prevention mechanism of this transmission is
As shown in the figure, when the spline teeth of the sleeve that mesh with the reverse dog teeth of the synchronization ring are separated in the longitudinal direction, and the dog teeth are disposed in the separated portion, The synchronization ring can be formed short in the longitudinal direction, the synchronization ring can be disposed even in a small space, and it is also preferable in terms of strength.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing an embodiment of the reverse gear noise prevention a side of the transmission according to the present invention, Fig. 2 is a developed view of Fig. 1, Fig. 3 is an exploded view of Fig. 1, and Fig. 4 is a sectional view showing another embodiment of the reverse gear noise prevention mechanism for a transmission according to the present invention, FIG. 5 is a developed view of FIG. 4, FIG. 6 is an exploded view of FIG. 4, and FIG. 7 is a conventional FIG. 8 is a sectional view showing an example of a synchronizer type reverse transmission mechanism, and FIG. 8 is a sectional view showing an example of a conventional direct mesh type reverse transmission mechanism. 2.--Reverse gear, 3--Forward gear,
5--Clutch hub, 6--Sleeve, 7.20--Synchronizing ring, 7A, 20A--
・Conical friction surface for forward stage, 7 B, 20 B---
--Conical friction surface for reverse, 9--Forward stage spline member, 11.13--Dog tooth, 12.23-- Index spring, 15---One forward stage synchro cone, 15B, 16B・−1・Conical outer peripheral surface, 16
・−・・−Reverse synchro cone, 1 day・−−−−
Reverse spline member, 21A21B---Spline tooth, 22--- Separation part. Applicant Isuri Motors Co., Ltd. Agent Patent Attorney O Naka

Claims (2)

[Claims] (1) It has dog teeth on both ends of the outer periphery that mesh with the spline teeth of the sleeve that fits into the clutch hub, and conical friction surfaces for forward gear and reverse gear on the inner circumferential surface, and the adjacent parts are integrated with a reduced diameter shape. a synchronizing ring, a forward synchro cone that is frictionally engaged with the forward conical friction surface, and a reverse synchro cone that is engaged with the forward synchro cone and frictionally engaged with the reverse conical friction surface. A transmission reverse gear noise prevention mechanism featuring: (2) Some of the spline teeth of the sleeve that mesh with the reverse dog teeth of the synchronization ring have two spline teeth in the longitudinal direction.
2. The mechanism for preventing reverse gear noise in a transmission according to claim 1, wherein the dog teeth of one of the synchronizing rings are disposed in a separated portion between the spline teeth.