JP7047323B2 - Shift fork and equipment - Google Patents

Description

The technique of the present disclosure relates to a shift fork for shifting a shift sleeve for shifting gears and the like , and a device including a shift fork .

Conventionally, in a speed change mechanism of a vehicle or the like, a shift fork has been used to shift a shift sleeve for shifting a speed change. In the shifting mechanism, the engaging protrusion of the shift fork slides in the outer peripheral groove of the shift sleeve. Various lubrication structures have been proposed in order to prevent wear and seizure of each sliding portion due to this sliding. For example, in Patent Document 1, in a shift fork that engages with the outer peripheral groove of the shift sleeve from below, the lubricating oil accumulated between the semicircular inner rib that loosely fits in the outer peripheral groove and the outer peripheral groove is scattered. To prevent this, it is disclosed that oil splash prevention steps (projections) are formed on both side surfaces of the inner rib.

Japanese Unexamined Patent Publication No. 11-11809

By the way, the mounting posture of the shift fork in the speed change mechanism is peculiar to the speed change mechanism, and various postures exist. In the shift fork, for example, the base of the shift fork configured to receive the shift force via the shift rod is located downward in the vertical direction, and the open portion of the substantially semicircular bifurcated main body is obliquely upward in the vertical direction. Some are used in a posture that opens from below. In a shift fork used in such a posture, for example, effectively guiding the lubricating oil that falls due to its own weight by the sliding portion between the shift fork and the shift sleeve enhances the lubricating ability in such a sliding portion. Above, it is valid.

Therefore, the technique of the present disclosure is such that in a device such as a speed change mechanism, the base of the shift fork is located downward in the vertical direction, and the open portion of the substantially semicircular bifurcated main body opens diagonally upward in the vertical direction. When the shift fork is engaged with the outer peripheral portion of the shift sleeve, the purpose is to make it possible to more effectively take in the lubricating oil into those sliding portions.

In order to achieve the above object, the technique of the present disclosure relates to a base configured to be able to transmit a shift force, and a substantially semicircular bifurcated base integrally formed with the base so as to be able to engage with the outer peripheral portion of the sleeve. A shift fork comprising a body portion having a mating portion, wherein the body portion forms an inner region in which the sleeve can be positioned and has two tips, each of the two tips. When a virtual cylinder having an engaging convex portion included in the engaging portion and corresponding to the sleeve is defined in the inner region, a front view of the shift fork from a direction along the center line of the virtual cylinder. The first engaging convex portion provided on the first tip portion of the two tip portions is provided on the second tip portion of the two tip portions with the center line interposed therebetween. 2 The position is such that the base portion is located downward in the vertical direction and the open portion of the main body portion opens diagonally upward in the vertical direction from diagonally downward in the front view. When there is a shift fork, the first tip portion is located on the lower side in the vertical direction with respect to the second tip portion, and the first tip portion is vertically on the tip side of the first engaging convex portion. The second tip portion is configured to have a first surface facing substantially upward in the direction, and the second tip portion faces the tip side of the second engaging convex portion and faces the substantially circumferential direction of the virtual cylinder. Provided is a shift fork that is configured to have a surface.

Preferably, in the shift fork in the posture in the front view, when a virtual surface including the center line of the virtual cylinder and extending in the vertical direction is defined, the first tip portion is divided into two by the virtual surface. The second tip portion of the region may be located in the first region, and the second tip portion may be located in the second region of the two regions together with the base portion.

The engaging portion may be made of synthetic resin.

The technique of the present disclosure also relates to an apparatus in which the shift fork is engaged with the outer peripheral portion of the sleeve in the posture. In the device, the sleeve is rotatable so that each position of the outer peripheral portion of the sleeve leaves the shift fork at the first tip and then reconnects with the shift fork at the second tip. It would be nice to have one.

According to the above technique of the present disclosure, since the above-mentioned configuration is provided, when the shift fork is engaged with the outer peripheral portion of the sleeve in the above-mentioned posture in a device such as a transmission mechanism, it is more effective for those sliding portions. It becomes possible to take in lubricating oil.

As an example, it is explanatory drawing of the shift fork in the speed change mechanism. It is a front view of the shift fork which concerns on this embodiment. It is a figure for demonstrating the shape of the shift fork of FIG. It is a front view of the shift fork which concerns on other embodiment.

Hereinafter, the shift fork according to the present embodiment will be described with reference to the attached figure. The same parts are designated by the same reference numerals, and their names and functions are also the same. Therefore, detailed explanations about them will not be repeated.

FIG. 1 is an explanatory diagram of a shift fork in a speed change mechanism as an example. As shown in the figure, in a general constant mesh type vehicle transmission 100, a plurality of main gears 102 and 104, each of which bears a predetermined stage, are rotatably attached to the main shaft MS. A clutch hub (not shown) is fixedly provided on the main shaft between the main gears 102 and 104. A shift sleeve 106 is attached to the outer peripheral side of the clutch hub so as to be slidable in the axial direction via a spline. The shift fork 108 is engaged with the outer peripheral groove 106a of the shift sleeve 106. The shift fork 108 is provided with engaging convex portions 108a that slidably contact the side wall surface of the outer peripheral groove 106a at both tip portions (only one tip portion is shown) of the substantially semicircular bifurcated main body portion. ing. Dog clutches 110 and 112 are fixed to the main gears 102 and 104, and synchronizer rings 114 and 116 are provided between the clutch hub and the dog clutches 110 and 112. Synchronizer rings 114, 116 are adjacent to both sides of the shift sleeve 106. The shift fork 108 is fixed to the shift rod 118. The shift rod 18 can be moved in the axial direction, that is, in both the directions of the arrows M1 and M2 in FIG. 1 based on the shift operation. When the shift fork 108 receives a shift force via the shift rod 118 based on the shift operation, the shift fork 108 is moved in the axial direction. Along with this, the shift sleeve 106 is also moved in the same direction. For example, when the shift fork 108 is moved from the state shown in FIG. 1 in the direction of the arrow M1 in the figure, the shift sleeve 106 is also interlocked (moved) in the direction of the arrow M1 and undergoes a synchronization action by the synchronizer ring, and then the synchronizer ring 114. And splines 120 and 122 formed on the outer peripheral portion of the dog clutch 110 are sequentially meshed with each other. As a result, the clutch hub and the dog clutch 110 are connected to each other, and the main gear 102 is selected.

This embodiment is applied to such a shift fork. The shift fork 10 according to the present embodiment will be described with reference to FIGS. 2 and 3. The shift fork 10 is used in a vehicle shifting mechanism. Similar to the shift fork described with reference to FIG. 1, the shift fork 10 engages (meshes) with a shift sleeve (sleeve gear) provided on a main shaft (not shown) which is a rotation shaft, and the shift fork 10 thereof is engaged with the shift sleeve (sleeve gear). It is used to constrain the movement of the shift sleeve along the axial direction of the main shaft and move the shift sleeve to select the main gear corresponding to the selection stage.

In FIG. 2, the shift fork 10 is represented by the posture of the shift fork 10 in a used state (see the description below for the posture) when the main shaft is arranged in the direction orthogonal to the paper surface. That is, although the orthogonal axis XYZ is shown in FIG. 2, the X axis in FIG. 2 corresponds to the axial direction of the main shaft, and the plane determined by the Y axis and the Z axis in FIG. 2, specifically, the paper surface is. Orthogonal to the axial direction of the main shaft.

The shift fork 10 includes a base portion 12 and a main body portion 14. FIG. 2 is a front view (front view) of the shift fork 10, and the base portion 12 and the main body portion 14 are arranged so as to extend along the paper surface. The posture of the shift fork 10 in FIG. 2 is the posture in the state of using the shift fork in the present embodiment, and the Z axis in FIG. 2 extends vertically in the vertical direction and is determined by the X axis and the Y axis in FIG. The plane substantially forms a horizontal plane. In FIG. 2, in the shift fork 10, the base portion 12 is located vertically downward in the shift fork 10 on a plane orthogonal to the axial direction of the main shaft (shaft), and the open portion 14a of the main body portion 14 is in the vertical direction. It is in a position to open diagonally upward and downward. In FIG. 2, a virtual cylinder C corresponding to the shift sleeve is defined in the inner region where the shift sleeve can be positioned, which is partitioned by the main body 14, and is represented by a broken line. In other words, FIG. 2 is a front view of the shift fork 10 from the direction along the center line C'of the virtual cylinder C.

The base 12 is configured to be able to transmit a shift force. Specifically, the base 12 is a place where the shift rod (not shown in FIG. 2) is fixed, and a hole 12a through which the shift rod is passed is formed. Therefore, when the shift rod is attached, the shift force can be transmitted to the base 12 via the shift rod.

The main body portion 14 is integrally formed with the base portion 12 and is formed in a substantially semicircular bifurcated shape. Therefore, the main body portion 14 forms the above-mentioned inner region in which the shift sleeve can be positioned, and has two tip portions 20, 22. When the tip portion (first tip portion) 20 of one of the two tip portions defines the virtual surface S including the center line C'of the virtual cylinder C and extending in the vertical direction in the above posture in the front view of FIG. , Which is located in one of the two regions (first region) S1 divided by the virtual surface S. Then, in the above posture of the front view of FIG. 2, the other tip portion (second tip portion) 22 has a base 12 in the other region (second region) S2 of the two regions divided by the virtual surface S. Located with. The main body portion 14 has an inner rib 16 and an engaging portion 18 on an inner surface (inner peripheral surface) forming an inner region thereof. The inner rib 16 extends in a substantially arc shape along the inner surface of the main body portion 14. In the shift fork 10 of the present embodiment, the engaging portion 18 is formed only on the above-mentioned tip portions 20 and 22, and here, the engaging portion 18 is composed of two engaging convex portions 24 and 26. The engaging portions 18 (24, 26) are thicker than the inner rib 16 in the thickness direction (X-axis direction) of the shift fork 10, and are radially inside (the center line C'side of the virtual cylinder C). ) Slightly protrudes. Therefore, when the shift fork 10 engages (engages) with the outer peripheral groove of the shift sleeve, the engaging portion 18 mainly abuts on the wall surface of the outer peripheral groove.

The engaging portion 18 is made of synthetic resin. More specifically, in the shift fork 10, the engaging portion 18 is made of PEEK (polyetheretherketone). However, the engaging portion 18 may be made of another material. The engaging portion 18 is fixed to the main body portion 14 so as to be fitted into a groove (not shown) at a predetermined position of the main body portion 14. It should be noted that this fixing is strengthened by using an adhesive in addition to the fitting. The engaging portion, that is, the engaging member can be fixed to the main body portion 14 by various joining means, but may be integrally configured with the main body portion from the beginning. The present invention does not limit the engagement portion to be made of a material other than synthetic resin.

Here, in FIG. 2, of the two tip portions 20 and 22, the engaging convex portion 24 provided on the first tip portion 20 on the lower side in the vertical direction is referred to as a first engaging convex portion, and the first tip portion is referred to. The engaging convex portion 26 provided on the second tip portion 22 located above the portion 20 in the vertical direction is referred to as a second engaging convex portion. As is clear from FIG. 2, the first engaging convex portion 24 is located at a position substantially facing the second engaging convex portion 26 with the above-mentioned center line C'of the virtual cylinder C interposed therebetween.

By the way, in the transmission in which the shift fork 10 engages with the shift sleeve in the above posture shown in FIG. 2, when the shift fork 10 is mounted on the vehicle and the vehicle is moving forward, the shift sleeve is counterclockwise as shown by an arrow A1 in FIG. It rotates in the clockwise direction. Therefore, in this transmission, the shift sleeve rotates so that each position of the outer peripheral portion of the shift sleeve leaves the shift fork 10 at the first tip portion 20 and then comes into contact with the shift fork 10 again at the second tip portion 22. It is possible. In the use state where the shift sleeve is rotated in this transmission, the sliding portion between the engaging protrusions 24 and 26 of the shift fork 10 and the outer peripheral groove of the outer peripheral portion of the shift sleeve is more effectively lubricated. The tips 20 and 22 of the shift fork 10 are shaped so that oil can be taken in, as described below. As will be clear from the following description, the first tip portion 20 is formed in a shape different from that of the second tip portion 22. First, the first tip portion 20 will be described.

The first tip portion 20 is located below the virtual cylinder C in FIG. 2, and includes a first engaging convex portion 24 that engages with the shift sleeve from the lower side in the vertical direction in the transmission. Then, the shift sleeve rotates so that each position of the shift sleeve at the first tip portion 20 leaves the shift fork 10. As described above, since various members and the like rotate in the case of the transmission, the lubricating oil repels from the inner surface of the case or drips from above. The first tip portion 20 particularly receives the first engaging portion thereof so as to effectively receive such lubricating oil and supply it to the sliding portion between the outer peripheral groove of the shift sleeve and the first engaging convex portion 24 of the shift fork. The tip side of the convex portion 24 is shaped. More specifically, the tip side of the first tip portion 20 with respect to the first engaging convex portion 24 is configured to have a first surface 30 facing substantially upward in the vertical direction. In FIG. 2, the first surface 30 is formed so as to substantially extend from the inner surface (inner peripheral surface) of the main body portion 14 to the outer surface. The first surface 30 is formed so as to function as a receiving tray for lubricating oil from above. Here, the first surface 30 is formed as a flat surface, but may have a curved surface or unevenness. Then, as shown in FIG. 2, the first surface 30 prevents the lubricating oil received on the first surface 30 from flowing to the sliding portion between the outer peripheral groove of the shift sleeve and the first engaging convex portion 24 of the shift fork. To encourage, it is tilted so that the inside is lower than the outside. The degree of this inclination can be arbitrarily determined, but here it is about 10 ° with respect to the horizontal plane.

The second tip portion 22 is located above the virtual cylinder C with respect to the virtual cylinder C in FIG. 2, and includes a second engaging convex portion 26 that engages with the outer peripheral groove of the shift sleeve from the upper side in the vertical direction in the transmission. Then, the shift sleeve can be rotated so that each position of the outer peripheral portion of the shift sleeve starts engaging with the shift fork at the second tip portion 22. Therefore, when the transmission in which the shift sleeve rotates in the direction of arrow A1 is operated, the lubricating oil adhering to the outer peripheral surface of the rotating shift sleeve is guided from the second tip portion 22 along the rotation direction of the shift sleeve. Further, lubricating oil may drip onto the shift sleeve from the inner surface side of the case of the transmission. The second tip portion 22 is particularly tipped above the second engaging convex portion 26 so as to supply such lubricating oil to the sliding portion between the outer peripheral groove of the shift sleeve and the second engaging convex portion 26 of the shift fork. The sides are shaped. More specifically, the tip side of the second tip portion 22 with respect to the second engaging convex portion 26 is short, that is, the portion protruding toward the tip side with respect to the second engaging convex portion 26 is configured to be reduced as much as possible. ing. As a result, the second tip portion 22 is configured to have a second surface 32 facing the substantially circumferential direction of the shift sleeve (that is, the virtual cylinder C) on the tip side of the second engaging convex portion 26. There is. In FIG. 2, the second surface 32 is formed so as to substantially extend from the inner surface (inner peripheral surface) of the main body portion 14 to the outer surface. Here, the second surface 32 is formed as a flat surface, but may have a curved surface or unevenness. Then, as shown in FIG. 2, the second surface 32 prevents the lubricating oil received on the second surface 32 from flowing to the sliding portion between the outer peripheral groove of the shift sleeve and the second engaging convex portion 26 of the shift fork. To encourage, it is tilted so that the inside is lower than the outside.

Here, the first surface 30 and the second surface 32 will be further described with reference to FIG. FIG. 3 shows a shift fork 10 having the same posture as that of FIG. In FIG. 3, an example of the case where both tip portions 20 and 22 have a symmetrical shape is shown by a broken line. In FIG. 3, the first surface 30 of the first tip portion 20 is relative to the virtual line L1 corresponding to the line extending the inner surface of the first engaging convex portion 24 of the main body portion 14 in the first tip portion 20 of FIG. And has an angle θ. That is, the first tip portion 20 has a shape in which the tip side thereof is omitted by this angle θ. The angle θ in this case is about 35 °, but this angle may be arbitrarily determined based on the above technical idea. The second tip portion 22 has a shape in the second tip portion 22 of FIG. 3 in which the tip side of the second engaging convex portion 26 is omitted by the length La. This length La is often determined in relation to the engaging convex portion 26, and can be arbitrarily determined. Since the first tip portion 20 and the second tip portion 22 are respectively shaped in this way, the second tip portion 22 is formed to be substantially shorter than the first tip portion 20.

As described above, the shift fork 10 is used in a predetermined transmission in the above posture shown in FIG. 2 in a state of being engaged mainly with the shift sleeve rotating in the rotation direction A1, and the first engaging convex portion 24 is used. The first tip portion 20 having the above-mentioned configuration has the first surface 30 having the above configuration, and the second tip portion 22 having the second engaging convex portion 26 has the second surface 32 having the above-mentioned configuration. Therefore, it becomes possible to more preferably guide (take in) the lubricating oil to the engaging portion, that is, the sliding portion of the shift fork 10 with the outer peripheral groove of the shift sleeve.

The shift fork 10 has been described above, but various changes can be made to it. FIG. 4 shows a shift fork 110 according to another embodiment. In the shift fork 110, the engaging portion 118 extends substantially over the inner circumference of the main body portion 14. That is, in the shift fork 110, the portion corresponding to each of the first engaging convex portion 24 and the second engaging convex portion 26 of the shift fork 10 of the above embodiment is also configured as a part of the engaging portion 118. are doing. In the shift fork 110, the engaging portion 118 is made of PEEK (synthetic resin) and fixed to the main body portion 14 in the same manner as the engaging portion 18. The material of the engaging portion 118 and the deformation variation regarding the mounting (fixing) method are the same as those of the engaging portion 18 of the shift fork 10 of the above embodiment. In the present invention, the engaging portion is not limited to being composed of one (connected) engaging convex portion or two engaging convex portions, but is composed of three or more engaging convex portions. Allow that.

The present invention is not limited to transmissions, but can be widely applied to devices (using shift forks) and shift forks thereof. For example, the shift fork according to the present invention may be widely applied to a synchro device of a two-axis drive type differential device.

Although the typical embodiment of the present invention has been described above, the present invention can be modified in various ways. Various substitutions and modifications are possible without departing from the spirit and scope of the invention as defined by the claims of the present application.

10 Shift fork 12 Base 14 Main body 16 Inner rib 18 Engagement part 20 First tip part 22 Second tip part 24 First engagement convex part 26 Second engagement convex part 30 First surface 32 Second surface

Claims (4)

It is a shift fork provided with a base portion configured to be able to transmit a shift force and a main body portion integrally formed with the base portion in a substantially semicircular bifurcated shape and having an engaging portion that can be engaged with the outer peripheral portion of the sleeve. hand,
The body portion comprises an inner region in which the sleeve can be located and has two tips.
A first engaging convex region, which is a part of the engaging portion, is provided on the first tip portion of the two tip portions, and the engaging portion is provided on the second tip portion of the two tip portions. A part of the second engaging convex region is provided,
When a virtual cylinder corresponding to the sleeve is defined in the inner region, in a front view of the shift fork from a direction along the center line of the virtual cylinder.
The first engaging convex region is located at a position substantially facing the second engaging convex region with the center line interposed therebetween.
When the shift fork is in a posture in which the base portion is located downward in the vertical direction and the open portion of the main body portion opens diagonally upward in the vertical direction from below in the front view.
The first tip portion is located on the lower side in the vertical direction as compared with the second tip portion.
The first tip portion is configured to have a first surface facing substantially upward in the vertical direction on the tip side of the first engaging convex region .
The second tip portion is configured to have a second surface facing the substantially circumferential direction of the virtual cylinder on the tip side of the second engaging convex region .
The engaging portion extends to the inner circumference of the main body portion between the first engaging convex region and the second engaging convex region in the circumferential direction.
Shift fork. In the shift fork in the posture in the front view,
When defining a virtual surface that includes the center line of the virtual cylinder and extends in the vertical direction,
The first tip portion is located in the first region of the two regions divided by the virtual surface.
The second tip is located in the second of the two regions together with the base.
The shift fork according to claim 1. The shift fork according to claim 1 or 2, wherein the engaging portion is made of synthetic resin. In an apparatus in which the shift fork according to any one of claims 1 to 3 is engaged with the outer peripheral portion of the sleeve in the posture.
The sleeve is rotatable so that each position of the outer peripheral portion of the sleeve leaves the shift fork at the first tip and then reconnects with the shift fork at the second tip.
Device.

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