JP2006226502A - Shift fork and rotating pawl mounting structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shift fork and rotating pawl mounting structure for preventing the fall-off of the rotating pawl during assembling in a transmission with a shift mechanism constructed of a cover ASSY while restricting the rotation of the rotating pawl at a preset angle or larger to be correctly mounted. <P>SOLUTION: In Claim 1, the shift fork and rotating pawl mounting structure, wherein a shaft of the rotating pawl is rotatably inserted through a mounting hole formed at the front end of a shift fork from the inside of the mounting hole, comprises a vertically oblong hole formed outside the mounting hole formed at the front end of the shift fork, a rotation restricting means at the end of the shaft of the rotating pawl inserted through the mounting hole for abutting on the peripheral wall of the oblong hole to restrict the rotation of the rotating pawl at a certain angle or larger, and a fall-off preventing means for preventing the fall-off of the rotating pawl from the mounting hole. In Claim 2, the mounting structure of Claim 1 comprises the rotation restricting means and the fall-off preventing means formed as plates which are fixed to the end of the shaft of the rotating pawl for abutting on the peripheral wall of the oblong hole formed at the front end of the shift fork. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a shift fork and a rotating claw mounting structure for selecting a gear of a transmission.

As is well known in the art, in a manual transmission, a shift fork is engaged with an outer peripheral groove of a synchro sleeve (hereinafter referred to as a “sleeve”), and the shift fork is moved in the direction of the transmission shaft to move the sleeve in the same direction. It is made to shift to and shift.
Conventionally, the shift fork has been subjected to induction hardening in order to prevent wear of the tip (claw portion) that engages and abuts the outer peripheral groove of the sleeve, or wear resistance as disclosed in Patent Document 1. A method such as fixing the sintered metal piece to the tip is adopted, but the shift fork of a manual transmission for large vehicles is made of copper alloy to improve the synchro performance and prevent wear of the tip. Nail is widely used.

  Thus, by adopting this rotating claw, even when the shift fork is bent by the load at the time of shift, the shift force to the sleeve can be input parallel to the sleeve from the sleeve center, thus preventing the sleeve from tilting. can do. As a result, detent forces that can be generated at three locations on the circumference can be generated uniformly, and the synchro ring can be pushed evenly, so that the synchro performance is improved.

In addition, by adopting a rotating claw, it is possible to use another material such as a copper alloy for the rotating claw. Unlike the case where the claw is integrally provided at the tip of the shift fork, there is a problem of wear due to sliding of the sleeve. Therefore, a cast iron shift fork can be used at a low price.
JP-A-9-196168

However, conventionally, the shift fork and the rotating claw have a structure in which the shaft portion of the rotating claw is simply fitted into the mounting hole provided at the tip of the shift fork.
For this reason, in a transmission in which the shift mechanism is configured by a transmission cover ASSY (transmission cover), it is impossible to assemble the rotating claw by visually observing whether or not the rotating claw is securely incorporated. The fitting method has a problem that the rotating claw falls off during assembly or the rotating claw rotates and cannot be correctly attached.

  The present invention has been devised in view of such circumstances, and even in a transmission in which the shift mechanism is configured by a cover ASSY, the rotation claw is prevented from falling off during assembly, and a predetermined rotation claw is also provided. An object of the present invention is to provide a shift fork and a rotating claw mounting structure that can prevent rotation more than an angle and correctly mount the rotating claw.

  In order to achieve such an object, the invention according to claim 1 is directed to a shift fork in which a shaft portion of a rotary claw is rotatably inserted into an attachment hole provided at a tip portion of the shift fork from the inside of the attachment hole. In the claw mounting structure, a long hole is formed in the vertical direction outside the mounting hole provided at the tip of the shift fork, and the end of the long hole is formed at the end of the shaft portion of the rotating claw inserted through the mounting hole. The present invention is characterized in that a rotation restricting means that abuts on the peripheral wall and restricts rotation of the rotating claw at a certain angle or more and a drop-off preventing means that prevents the rotating claw from dropping from the mounting hole are provided.

  The invention according to claim 2 is the shift fork and rotating claw mounting structure according to claim 1, wherein the rotation restricting means and the drop-off preventing means are fixed to the end of the shaft portion of the rotating claw. The invention according to claim 3 is characterized in that the shift fork and the rotary claw mounting structure according to claim 1 are rotated. The restricting means and the drop-off preventing means are formed of a convex portion obtained by drilling a hole at the shaft end of the rotating claw and caulking the shaft end from the inside along the long hole.

  Furthermore, the invention according to claim 4 is the shift fork and rotating claw mounting structure according to any one of claims 1 to 3, wherein the tip of the rotating claw is formed in the outer circumferential groove of the synchro sleeve. It is characterized by a tapered shape that can be easily engaged.

  According to the first to third aspects of the invention, even in the transmission in which the shift mechanism is configured by the cover ASSY, the rotation claw is prevented from falling off during the assembly, and the rotation claw has a predetermined angle. Since the rotation claw can be correctly mounted by restricting the above rotation, there is an advantage that the rotation claw can be employed in the shift fork of the transmission in which the shift mechanism is configured by the cover ASSY.

  And according to the invention which concerns on Claim 4, even if a rotation nail | claw rotates in an assembly | attachment, it has the advantage that the assembly | attachment to a sleeve becomes easy.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1 to 7 show an embodiment of the invention according to claim 1, claim 2 and claim 4. In FIG. 1, reference numeral 1 is a cast iron shift fork. The boss portion 5 is formed with a shift fork shaft insertion hole 3 (not shown), and the fork portion 7 is bifurcated from the boss 5. As shown in FIGS. A mounting hole 11 having a circular cross section is provided on the distal end portion 9 on the same axis.

As shown in FIG. 3, a rotary claw 15 is rotatably attached to the distal end portion 9 by inserting a shaft portion 13 having a circular cross section from the inside of both mounting holes 11.
As shown in FIG. 2 to FIG. 4, on the outer side of the tip portion 9 where the mounting hole 11 is opened, end milling is performed in the vertical direction of the mounting hole 11 to form an oblong slot 17 having a certain depth. The elongated hole 17 has a shape in which the minor diameter dimension m is narrower than that of the mounting hole 11.

  On the other hand, as shown in FIGS. 3 and 5, the rotary claw 15 includes a block-like claw body 19 formed of a copper alloy and a shaft portion 13 having a circular cross section integrally projecting from the center thereof. In order to improve the assembling property to the sleeve, the upper and lower tip portions 21 and 23 of the claw body 19 are tapered. As shown in FIGS. 2, 3 and 5, a communication groove 25 having the same width as the short diameter dimension m of the long hole 17 is formed at the end of the shaft portion 13 protruding from the mounting hole 11. 19 is milled along the vertical direction of 19, and a screw hole 27 is provided along the axial center of the shaft portion 13. As shown in FIG. 3, the bottom 29 of the communication groove 25 is disposed in the elongated hole 17. Has been.

As shown in FIGS. 2 and 3, an oval plate 31 as shown in FIG. 6 is disposed in the communication groove 25, which is slightly smaller than the elongated hole 17, and is screwed into the screw hole 27. Further, the plate 31 prevents the rotary claw 15 from falling out of the mounting hole 11 (the tip 9 of the shift fork 1).
Since the plate 31 has a slightly smaller oval shape than the elongated hole 17 as described above, a slight gap n is formed between the peripheral wall of the elongated hole 17 and the plate 31 as shown in FIG. Exists. For this reason, as shown in FIG. 7, the rotating claw 15 can swing in the rotation direction of the shaft portion 11 by the gap n, and the plate 31 comes into contact with the peripheral wall of the elongated hole 17 so that the rotating claw 15 is kept constant. Rotation beyond this angle is restricted.

In addition, in FIG. 6, reference numeral 35 denotes a screw insertion hole formed in the plate 31.
Since the present embodiment is configured as described above, the rotating claw 15 is attached to the shift fork 1 by inserting the shaft portion 13 of the rotating claw 15 into the mounting hole 11 from the inside of the mounting hole 11, as shown in FIG. As shown in FIG. 3, the plate 31 may be screwed into the communication groove 25 and the long hole 17 at the end of the shaft portion 13 protruding from the mounting hole 11.

  Thus, by attaching the rotary claw 15 to the shift fork 1 in this manner, the plate 31 prevents the rotary claw 15 from falling off from the mounting hole 11, and as shown in FIG. It swings in the rotational direction of the shaft portion 11 by a slight gap n between the peripheral wall of the long hole 17 and the plate 31, and the plate 31 comes into contact with the peripheral wall of the long hole 17 and exceeds a certain angle of the rotary claw 15. Will be restricted.

And since the front-end | tip parts 21 and 23 of the nail | claw main body 19 were made into the tapered shape, even if the rotation nail | claw 15 rock | fluctuates and rotates only the clearance gap n as mentioned above, it can be easily assembled | attached to the outer peripheral groove | channel of a sleeve.
As described above, in this embodiment, the plate 31 is screwed to the end of the shaft portion 13 of the rotary claw 15 to prevent the rotary claw 15 from falling off the mounting hole 11 by the plate 31 and the plate 31 is long. Since the rotation claw 15 abuts on the peripheral wall of the hole 17 and functions as a rotation restricting means for restricting the rotation of the rotating claw 15 beyond a certain angle, according to the present embodiment, the shift mechanism includes the cover ASSY. However, the rotation claw 15 can be prevented from falling off during assembly, and the rotation claw 15 can be properly mounted by restricting the rotation of the rotation claw 15 beyond a predetermined angle. The rotating claw 15 can be employed in the shift fork 1 of the transmission whose mechanism is constituted by the cover ASSY.

Further, as described above, the tip portions 21 and 23 of the claw body 19 are tapered, so that even when the rotating claw 15 is rotated by the gap n as described above, the claw body 19 is assembled to the outer circumferential groove of the sleeve. There is an advantage that attachment is easy.
The elongated hole 17 and the plate 31 are not necessarily limited to an oval shape, and can be appropriately selected as long as they can achieve the intended purpose.

  FIGS. 8 to 10 show a shift fork and rotating claw mounting structure according to one embodiment of claims 1, 3, and 4. As described above, in the embodiment of FIG. The plate 31 screwed to the shaft portion 13 is provided with a function for preventing the rotation claw 15 from falling off and a function for restricting rotation. In this embodiment, instead of the plate 31, the end portion of the shaft portion of the rotation claw is elongated from the inside. By caulking in the vertical direction, the rotation claw is prevented from falling off and the rotation over a certain angle is restricted.

In the following, the present embodiment will be described with reference to FIGS. 8 to 10. However, the same components as those in the embodiment of FIG.
In FIG. 8, reference numeral 37 denotes a rotating claw that attaches to the mounting hole 11 of the shift fork 1. As shown in FIG. 9, the rotating claw 37 is integrally formed with a block-like claw body 39 formed of a copper alloy at the center. The claw body 39 is formed in the same shape as the claw body 19 with the shaft section 41 having a circular cross section projecting from the side, and the top and bottom tips 43 and 45 are formed in the same shape as the claw body 19. It has a tapered shape.

  As shown in FIGS. 8 and 9, in this embodiment, the end of the shaft portion 41 protruding from the mounting hole 11 is drilled to provide a hole 47, and the end of the shaft portion 41 is elongated from the inside. By caulking in the vertical direction along the hole 17, two projecting portions 49 and 51 that can contact the peripheral wall of the elongated hole 17 are provided. The projections 49 and 51 prevent the rotary claw 37 from falling off the mounting hole 11 (the tip 9 of the shift fork 1). As shown in FIG. A slight gap p is provided between the peripheral wall 17 and the rotary claw 37 can swing in the rotational direction of the shaft portion 11 by the gap p as shown in FIG. Both convex parts 49 and 51 are brought into contact with the peripheral wall, and the rotation of the rotating claw 37 over a certain angle is restricted.

Since the present embodiment is configured in this way, the rotation claw 37 is attached to the shift fork 1 by previously drilling holes in the end portion of the shaft portion 41 to provide the holes 47.
Then, after the shaft portion 41 of the rotary claw 37 is inserted into the mounting hole 11 from the inside of the mounting hole 11, the end portion of the shaft portion 41 protruding from the mounting hole 11 is elongated from the inside as shown in FIGS. 8 and 9. The protrusions 49 and 51 may be provided by caulking in the vertical direction along the line 17.

  Thus, by projecting the protrusions 49 and 51 in this way, the rotation claw 37 can be prevented from falling off from the mounting hole 11, and as shown in FIG. 49, 51 and the peripheral wall of the elongated hole 17 are swung in the rotational direction of the shaft portion 41, and the convex portions 49, 51 come into contact with the peripheral wall of the elongated hole 17 to The rotation beyond a certain angle is restricted.

And since the front-end | tip parts 43 and 45 of the nail | claw main body 39 were made into the taper shape, even if the rotation nail | claw 37 rock | fluctuates and rotates only the clearance gap p as mentioned above, it can be easily assembled | attached to the outer peripheral groove | channel of a sleeve.
As described above, in the present embodiment, the projections 49 and 51 projecting from the end of the shaft portion 41 of the rotary claw 37 prevent the rotary claw 37 from falling off the mounting hole 11, and the projections 49 and 51 Since it functions as a rotation restricting means that abuts on the peripheral wall of the long hole 17 and restricts the rotation of the rotating claw 37 beyond a certain angle, as in the embodiment of FIG. The rotating claw 37 can be employed in the shift fork 1 of the transmission.

  Further, as described above, this embodiment also has the tip portions 43 and 45 of the claw body 39 having a tapered shape, so that even when the rotating claw 37 is rotated by the gap p as described above, There is an advantage that the assembly to the outer circumferential groove becomes easy.

It is a front view of the shift fork used for one embodiment of claim 1, claim 2, and claim 4. It is a principal part enlarged side view of the attachment structure of the shift fork and rotary claw which concerns on one Embodiment of Claim 1, Claim 2 and Claim 4. It is the sectional view on the AA line of FIG. It is an enlarged side view of the front-end | tip part of a shift fork. It is a side view of a rotation nail. It is a front view of a plate. It is a principal part expanded side view of the attachment structure which concerns on one Embodiment of Claim 1, Claim 2, and Claim 4 which shows the rotation state of a rotation nail | claw. It is a principal part enlarged side view of the attachment structure of the shift fork and rotary claw which concerns on one Embodiment of Claim 1, Claim 3 and Claim 4. It is the BB sectional drawing of FIG. It is a principal part expanded side view of the attachment structure which concerns on one Embodiment of Claim 1, Claim 3, and Claim 4 which shows the rotation state of a rotation nail | claw.

Explanation of symbols

1 Shift fork 3 Insertion hole 5 Boss portion 7 Fork portion 9 Tip portion 11 Mounting hole 13, 41 Shaft portion 15, 37 Rotating claw 17 Long hole 19, 39 Claw body 25 Communication groove 27 Screw hole 31 Plate 47 Hole 49, 51 Convex

Claims (4)

In the mounting structure of the shift fork and the rotating claw in which the shaft portion of the rotating claw is rotatably inserted from the inside of the mounting hole into the mounting hole provided at the tip of the shift fork.
A long hole is formed in the vertical direction outside the mounting hole provided at the tip of the shift fork,
Rotation restricting means for restricting rotation of the rotating claw over a certain angle by contacting the peripheral wall of the elongated hole at the end of the shaft portion of the rotating claw inserted through the mounting hole, and dropping of the rotating claw from the mounting hole A structure for mounting a shift fork and a rotating claw, characterized in that a drop-off preventing means is provided for prevention.   2. The plate according to claim 1, wherein the rotation restricting means and the drop-off preventing means are plates fixed to the end of the shaft portion of the rotating claw and capable of coming into contact with a peripheral wall of a long hole provided at the tip of the shift fork. Shift fork and rotating claw mounting structure.   The rotation restricting means and the drop-off preventing means are each formed of a convex portion obtained by drilling a hole in the shaft end portion of the rotating claw and caulking the shaft portion end portion in the vertical direction along the elongated hole from the inside. Item 2. The mounting structure of the shift fork and rotating claw according to item 1. The shift fork and rotary claw attachment structure according to any one of claims 1 to 3, wherein a tip end portion of the rotary claw has a tapered shape that can be easily engaged with an outer peripheral groove of the synchro sleeve.

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