JPH0566365U - Shift fork support structure - Google Patents

Abstract

(57) [Summary] [Purpose] The movement amount of the shift fork can be adjusted. A jaw 27 fixed to a shift rail 26 is supported on an upper end portion of a shift fork 23 so as to be relatively rotatable,
By attaching the shift fork 23 to the fixed bar 22 on the transmission case 21 side and changing the support points of the jaw 27 and the shift fork 23, the movement amount of the shift fork 23 in the same shift stroke is changed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a shift fork support structure in which the stroke amount of the shift fork can be freely changed with respect to the movement amount of the shift rail.

[0002]

[Prior Art]

 FIG. 4 shows a cross section of a transmission having a conventional shift fork support structure, and FIG. 5 shows a view taken along the line VV in FIG.

The illustrated example has five forward steps and one reverse step, in which a gear unit 3 including a main shaft 1 and a counter shaft 2, a shift fork 4, a shift rail 5 and the like are housed in a cast iron integrated transmission case 6. ing.

In the figure, 7 is an upper case for accommodating the gear shift sliding lever 8 and the like, which is directly mounted on the upper surface of the transmission case 6. The front of the transmission case 6 is closed by a clutch housing 9.

Generally, in the main shaft 1, the reverse gear 10 is formed in front of the first speed gear 11 due to processing problems and the like. Then, the movement of the shift rail 5 needs to be reversed and transmitted due to a problem in the shift pattern. In the above-mentioned transmission, this is done by using the swing type shift fork 12.

The swing type shift fork 12 has an upper end portion 12 a fitted to the shift rail 5 via a jaw 15 for preventing the drop, and is made to move in a vertical direction by a reaction pin 14 which is press-fitted to the left and right of the transmission case 6. The center is rotatably supported. Therefore, when the shift rail 5 moves forward, the lower end of the swing type shift fork 12 moves backward.

[0007]

[Problems to be solved by the device]

 When the shift stroke (stroke amount of the shift lever) of each shift speed is made equal, the adjustment range of the shift amount of the shift rail 5 is limited by the transmission force of each gear and spline specifications. In particular, there is a tendency to reduce the movement amount of the shift rail 5 in order to reduce the size of the simultaneous meshing portion. Problems such as missing gears will occur.

[0008]

[Means for Solving the Problems]

 According to the configuration of the present invention for solving the above-mentioned problems, the shift fork is rotatably supported on the transmission case side, one end of the jaw is fixed to the shift rail, and the support point of the shift fork on the transmission case side is sandwiched. Is characterized in that the other end of the jaw is connected to the shift fork so as to be relatively rotatable.

[0009]

[Action]

 By changing the connecting position of the shift fork and jaw, the movement amount of the shift lever in the same shift stroke can be changed variously.

[0010]

【Example】

 FIG. 1 is a front view of a main part of a transmission showing a shift fork support structure according to an embodiment of the present invention, and FIG. 2 is a view taken along the line II-II in FIG.

A fixed bar 22 is attached to the transmission case 21, and an upper end portion of a shift fork 23 is rotatably supported by the fixed bar 22. A piece 24 is rotatably attached to the lower end of the shift fork 23. 25 is a snap ring.

The upper end of the jaw 27 is fixed to the shift rail 26, and the other end of the jaw 27 is rotatably connected to the shift fork 23 with a support point of the shift fork 23 on the fixed bar 22 interposed therebetween. ing. The jaw 27 has a bifurcated shape and is supported via a rivet 28 with the shift fork 23 interposed therebetween.

When the shift rail 26 is moved by the gear shift operation, the shift fork 23 is rotated around the fixed bar 22 via the jaw 27, and the sleeve 29 is moved. The moving amount S of the sleeve 29 can be represented by S = {(A + B) / A} · X ... (1). However, A is the distance from the fixed bar 22 to the rivet 28, B is the distance from the rivet 28 to the piece 24, and X is the movement amount of the shift rail 26.

Therefore, by changing the support positions of the jaw 27 and the shift fork 23, the rotation amount of the shift fork 23, that is, the movement amount S of the sleeve 29 can be adjusted.

As shown in FIG. 3, it is also possible to form the upper end of the shift fork 23 into a bifurcated shape so as to sandwich the jaw 27.

[0016]

[Effect of the device]

 In the shift fork support structure of the present invention, the jaw fixed to the shift rail is supported rotatably relative to the shift fork attached to the transmission case side, so that the same support can be obtained by changing the supporting points of the jaw and the shift fork. It is possible to change the movement amount of the shift fork in the shift stroke. As a result, the shift stroke can be reduced without adversely affecting the gear shift, and the transmission can be downsized.

[Brief description of drawings]

FIG. 1 is a front view of a main part of a transmission showing a shift fork support structure according to an embodiment of the present invention.

FIG. 2 is a view taken along the line II-II in FIG.

FIG. 3 is a front view of a main part of a transmission showing a shift fork support structure according to another embodiment of the present invention.

FIG. 4 is a sectional view of a transmission having a conventional shift fork support structure.

5 is a view taken along the line VV in FIG.

[Explanation of symbols]

 21 transmission case 22 fixed bar 23 shift fork 26 shift rail 27 jaw 29 sleeve

Claims (1)

[Scope of utility model registration request] 1. A shift fork is rotatably supported on the transmission case side, one end of the jaw is fixed to a shift rail, and the other end of the jaw is attached to the shift fork while sandwiching a support point of the shift fork on the transmission case side. A shift fork support structure characterized by being connected so as to be rotatable relative to each other.