JPH07133865A - Shift fork - Google Patents

Abstract

PURPOSE:To easily and accurately mount a slide member made of abrasion resistance material such as resin or aluminum alloy by forming a projection on the slide member for engagement with the hole of a fork tooth section, and fitting the slide member to the fork section, while a positional relationship being fixed between the projection and the hole. CONSTITUTION:A shift fork 1 is formed out of cast iron, steel or aluminum alloy, and has a tooth section 3 on the end of a fork section 2. Also, two holes 4 in parallel to the axial line of the radial plane 3B of the section 3 are drilled through the thrust plane 3A thereof. A slide member 5 is made of abrasion resistant synthetic resin and formed to have U-shaped cross section. The internal side of the member 5 opposite to the thrust plane section 5A thereof is in contact with the plane 3A, while the internal side of the radial plane section 5B is in contact with the plane 3B. In addition, projections 6 to be coupled to the holes 4 are provided on the internal side of the member 5 faced to the thrust plane section 5A. Also, a connection piece 7 is made of synthetic resin, and coupled to the holes 4. The slide member 5 is caulked to the tooth section 3 and the projections 6 are engaged with the holes 4. Thereafter, the projections 6 and the connection piece 7 are jointed to each other via ultrasonic welding. According to this construction, the slide member 5 can be easily and accurately mounted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift fork which is one component in a transmission of an automobile or the like.

[0002]

2. Description of the Related Art Generally, this kind of shift fork 11 is
As illustrated in FIG. 9, a boss portion 13 into which a fork shaft (not shown) is inserted is formed in the base end portion 12, and the fork portions 14, 14 branched into two forks from the base end portion 12 are provided at the tips thereof. Each has a claw portion 15 that is fitted into a groove portion of a synchronizer sleeve (not shown) and slides. To prevent wear of the claw portion 15 and reduce sliding contact resistance, as illustrated in FIG. A sliding member 16 made of wear-resistant resin and having a U-shaped cross-section is attached to it (see Japanese Patent Application Laid-Open No. 2-190672).

Conventionally, the sliding member 16 is molded separately from the claw portion 15, and as shown in FIG.
8 between the claw 15 and the sliding member 16 and the claw 15
The resin composition 20 is filled by injection into the hole 19 provided in the claw portion 15 and the sliding member 16 are integrally fixed (Japanese Patent Laid-Open Nos. 3-153964 and 2-153964).
(See No. 112924).

[0004]

By the way, in the above-mentioned prior art, when the sliding member 16 is mounted on the shift fork claw portion 15, the molds 17 and 18 are used. To receive the mold 17,18
Is easily deformed, its accuracy is difficult to maintain, and the accuracy of the mold determines the quality of the finished product after mounting the sliding member.
It is necessary to improve the precision of the shift fork, which causes a problem of cost increase.

The present invention has been made in view of the above situation, and an object thereof is to provide a protrusion for engaging with a hole formed in a claw portion on a sliding member,
It is an object of the present invention to provide a shift fork capable of easily, reliably and accurately mounting a sliding member without using a die, thereby achieving cost reduction.

[0006]

In order to achieve the above object, the present invention takes the following technical means. That is, according to the present invention, the shift fork claw portion is engaged with the slide member formed separately from the fork claw portion and made of a wear-resistant material such as resin or aluminum alloy and the hole provided in the claw portion. The sliding member is attached to the fork claw portion by providing a protrusion and fixing the positional relationship between the protrusion and the hole.

Further, according to the present invention, a resin connecting piece is fitted in the hole of the shift fork claw portion, and projections provided on opposite inner side surfaces of both thrust surface portions of the resin sliding member are fitted at both ends of the piece. It is characterized by being integrated by welding. Furthermore, the present invention is characterized in that the sliding member is made of an aluminum alloy, and the projections provided on the opposing inner side surfaces of both thrust surface portions are engaged and fixed in the holes.

[0008]

According to the present invention, the sliding member formed in advance is fitted on the shift fork claw portion, and the projection provided on the inside of the thrust member facing both thrust surfaces of the sliding member into the hole provided in the claw portion. Can be easily mounted by fixing and engaging with, and a mold or the like is unnecessary. Further, according to the present invention, a resin connecting piece is fitted in a hole provided in the claw portion of the shift fork, and a protrusion provided on the inner surface of each of the thrust surface portions of the resin sliding member facing each other is provided on the piece. After they are brought into contact with each other, they can be fixed and integrated by an adhesive means such as ultrasonic welding, and a mold is not required.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show a first embodiment of the present invention (only one claw portion of the shift fork of FIG. 9), the shift fork 1 is made of cast iron, steel or aluminum alloy, and the fork portion 2 thereof is shown.
A claw portion 3 that fits in a groove portion of a synchronizer sleeve (not shown) is formed at the tip of the claw portion 3, and a thrust surface 3A of the claw portion 3 has a hole 4 having an axis parallel to the axis of the radial surface 3B.
They are provided in parallel with each other and in a penetrating manner. The number of the holes 4 may be one or three or more, and it is preferable to form a plurality of holes.

Reference numeral 5 denotes a sliding member, which is formed in a U-shaped cross section from a wear-resistant material such as a wear-resistant synthetic resin having excellent thermal conductivity and oil retention, and has thrust surface portions 5A, 5A facing each other. Contact the thrust surfaces 3A, 3A of the claw portion 3, and the inner surface of the radial surface portion 5B is the radial surface 3
The thrust surface portion 5 is formed so as to come into contact with B.
Protrusions 6 and 6 that fit into the holes 4 of the claw portion 3 are provided on the inner surfaces of the A and 5A facing each other.

Reference numeral 7 denotes a connecting piece, which is made of a synthetic resin which is the same as or different from that of the sliding member 5 and is formed into a cylindrical shape having a size that can be fitted into the hole 4. Therefore, when the sliding member 5 is attached to the claw portion 3, first, the connection piece 7 is attached to the hole 4 of the claw portion 3.
The slide member 5 and the thrust surface portion 5A thereof.
After slightly pushing the ends of the projections outwards so as to cover the claw portions 3, and engaging the projections 6 and 6 with the holes 4, the projections 6 and the connecting piece 7 are superposed. The sliding member 5 can be firmly attached to the claw portion 3 by welding and unifying with the sonic welding means.

As the material of the sliding member 5 and the connecting piece 7, thermosetting resin can be used in addition to thermoplastic resin such as polyamide resin, tetrafluoroethylene, glass fiber reinforced resin and the like. According to the first embodiment described above, the molding accuracy of the sliding member 5 is ensured and the conventional mold is not required.
It does not depend on the precision of the mold, it is easy and easy to mount, and the cost increase can be eliminated.

FIG. 4 shows the essential parts of a second embodiment of the present invention.
The difference from the first embodiment is that the sliding member 5 is made of aluminum alloy, the connecting piece is eliminated, and the projections 6 and 6 are engaged or press-fitted into the holes 4 of the claw portion 3. 1
Compared to the embodiment, the number of parts is reduced and the assembling workability is improved. In addition, in the second embodiment, the protrusion 6 can be fitted into the hole 4 via an adhesive.

FIG. 5 shows the essential parts of a third embodiment of the present invention.
The difference from the first embodiment is that the sliding member 5 is divided into two and only the thrust surface portions 5A and 5A are eliminated, and the radial surface portions are eliminated, and both thrust surface portions 5A and 5A are connected by the connection piece 7. It is integrated. FIG. 6 shows an essential part of a fourth embodiment of the present invention. The difference from the first embodiment is that the sliding member 5 is divided into two parts in the middle of the radial surface part 5B, and both thrust surface parts 5A. , 5A are connected and integrated by the connecting piece 7.

FIG. 7 shows the essential parts of a fifth embodiment of the present invention.
The difference from the fourth embodiment is that the connection piece 7 is eliminated and the projections 6A, 6A are made longer, respectively, and the opposing surfaces of both projections 6A, 6A are brought into contact with each other, and the projections 6A, 6A are welded together by ultrasonic welding means. This is the point that the assembly workability is improved. FIG. 8 shows an essential part of the sixth embodiment of the present invention. The difference from the third embodiment is that the connecting piece 7 is eliminated and the projection 6A of one thrust surface portion 5A of the sliding member 5 is lengthened,
This is a point in which the projection 6 of the other thrust surface portion 5A is brought into contact with the projections 6 and 6A to be welded and integrated by ultrasonic welding means, which improves the assembling workability.

The present invention is not limited to the above-mentioned embodiment, and for example, the sliding member 5 can be adhered by an appropriate adhesive agent in addition to welding, and the sliding members 5 in the third to sixth embodiments. Not only a synthetic resin but also an aluminum alloy can be applied as the material 5. When the sliding member 5 is made of an aluminum alloy, the connection piece 7 can also be made of an aluminum alloy and welded by spot welding or the like.

[0017]

As described above, according to the present invention, the shift fork claw portion is provided with the sliding member formed separately from the fork claw portion and made of a wear-resistant material such as resin or aluminum alloy. Since a protrusion that engages with the hole provided in the fork is provided and the positional relationship between the protrusion and the hole is fixed, the sliding member is attached to the fork claw portion,
The sliding member can be mounted without using a die, the assembling workability of the sliding member can be improved, the mounting can be carried out easily and securely with high accuracy, and the product quality can be improved and the cost can be reduced.

Further, according to the present invention, a resin connecting piece is fitted in the hole of the shift fork claw portion, and projections provided on opposite inner surfaces of both thrust surface portions of the resin sliding member are provided at both ends of the piece. Since it is characterized by being integrated by welding, the sliding member can be securely and firmly mounted without backlash. Furthermore, the present invention is characterized in that the sliding member is made of an aluminum alloy, and the projections provided on the opposing inner side surfaces of both thrust surface portions are engaged and fixed in the holes, so the number of parts is reduced. Therefore, it is possible to improve workability and reduce assembly work cost.

[Brief description of drawings]

FIG. 1 is a sectional view showing a main part of a first embodiment of the present invention.

FIG. 2 is a perspective view showing a mounting completion state of the embodiment.

FIG. 3 is an exploded perspective view of the embodiment.

FIG. 4 is a sectional view showing an essential part of a second embodiment of the present invention.

FIG. 5 is a sectional view showing an essential part of a third embodiment of the present invention.

FIG. 6 is a sectional view showing an essential part of a fourth embodiment of the present invention.

FIG. 7 is a sectional view showing a main part of a fifth embodiment of the present invention.

FIG. 8 is a sectional view showing an essential part of a sixth embodiment of the present invention.

FIG. 9 is a perspective view showing an example of a shift fork.

FIG. 10 is a perspective view showing a conventional example.

FIG. 11 is an explanatory diagram of the conventional example.

[Explanation of symbols]

 1 shift fork 2 fork part 3 claw part 4 hole 5 sliding member 5A thrust surface part 6 protrusion 7 connection piece

Claims (3)

[Claims] 1. A shift fork pawl portion, a sliding member formed separately from the fork pawl portion and made of a wear-resistant material such as an aluminum alloy, and a projection engaging with a hole provided in the pawl portion. And a sliding member is attached to the fork claw portion by fixing the positional relationship between the protrusion and the hole. 2. A resin connecting piece is fitted into the hole of the shift fork claw portion, and projections provided on opposite inner surfaces of both thrust surface portions of the resin sliding member are welded and integrated at both ends of the piece. The shift fork according to claim 1, wherein 3. The shift fork according to claim 1, wherein the sliding member is made of an aluminum alloy, and projections provided on opposite inner side surfaces of both thrust surface portions are engaged and fixed in the holes.