A transmission shift fork mechanism

Abstract

The present invention discloses a transmission shift fork mechanism, which includes a shift fork assembly and a synchronizer assembly. The shift fork assembly includes a shift fork shaft, a shift fork connecting sleeve and a shift fork; the shift fork of the shift fork assembly is fixedly connected to the shift fork shaft through the shift fork connecting sleeve; the end of the shift fork is sleeved with a metal sleeve; the outer ring side wall of the synchronizer sleeve of the synchronizer assembly is circumferentially provided with a sleeve groove; when working, the shift fork assembly moves, driving the shift fork to move, so that the upper friction surface and the lower friction surface of the metal sleeve contact the upper and lower surfaces of the sleeve groove on the synchronizer sleeve, pushing the synchronizer sleeve to move and shift. The mechanism avoids the functional problems of the transmission hitting teeth and shifting out of gears caused by the shift fork being damaged and causing the synchronizer sleeve shifting stroke to be not in place, thereby improving the shifting quality of the transmission and reducing the production cost.

Description

Technical Field

[0001] The invention relates to the field of transmissions, and in particular to a transmission shift fork mechanism. Background Art

[0002] The prior art transmission shift fork mechanism Figures 1 to 4 As shown. The transmission shift fork mechanism includes: a shift fork assembly 1 and a synchronizer assembly 2. The shift fork assembly 1 is provided with a shift fork shaft 12, a shift fork connecting sleeve 13, and a shift fork 14. The shift fork assembly 1 is slidably connected to the shaft hole of the transmission case through the shift fork shaft upper end 122 and the shift fork shaft lower end 121 on the shift fork shaft 12. The shift fork 14 is fixedly connected to the shift fork shaft 12 through the shift fork connecting sleeve 13. The end 0142 on the shift fork 14 is matched with a plastic sleeve 0141 connected by injection molding through an inner cavity 01412. The synchronizer gear sleeve 21 of the synchronizer assembly 2 has a gear sleeve groove 211 on the outer ring circumferentially.

[0003] When shifting gears, the shift fork assembly 1 moves, driving the shift fork 14 to move, so that the upper and lower friction surfaces 01411 of the plastic sleeve 0141 contact the upper and lower surfaces of the tooth sleeve groove 211 on the synchronizer tooth sleeve 21, pushing the synchronizer tooth sleeve 21 to move and shift gears. Due to the high-speed rotation of the synchronizer tooth sleeve 21, accompanied by the inevitable deflection of the synchronizer tooth sleeve 21 around the central axis, the upper and lower surfaces of the tooth sleeve groove 211 will continuously knock and unbalance the upper and lower friction surfaces 01411 of the plastic sleeve 0141, eventually causing the upper and lower friction surfaces 01411 to crack, collapse, fall off, excessive wear, etc., thereby causing the synchronizer tooth sleeve 21 to shift gears incompletely, resulting in functional problems such as gear knocking and gear disengagement of the transmission. Summary of the invention

[0004] The invention discloses a transmission shift fork mechanism, which can improve the wear resistance and impact resistance of the shift fork, extend the service life of the shift fork, avoid functional problems such as tooth knocking and gear disengagement caused by shift fork wear, and improve the shifting quality of the transmission.

[0005] A transmission shift fork mechanism disclosed in the present invention comprises a shift fork assembly and a synchronizer assembly;

[0006] The shift fork assembly comprises a shift fork shaft, a shift fork connecting sleeve and a shift fork; the shift fork of the shift fork assembly is fixedly connected to the shift fork shaft through the shift fork connecting sleeve; the end of the shift fork is sleeved with a metal sleeve; the metal sleeve is composed of two upper and lower friction surfaces, the end of the upper friction surface is an upper end protrusion, and the end of the lower friction surface is a lower end protrusion, and the upper end protrusion and the lower end protrusion face each other and fix the end of the shift fork;

[0007] The outer ring side wall of the synchronizer gear sleeve of the synchronizer assembly is circumferentially provided with a gear sleeve groove;

[0008] During operation, the shift fork assembly moves, driving the shift fork to move, causing the upper and lower friction surfaces of the metal sleeve to contact the upper and lower surfaces of the sleeve groove on the synchronizer sleeve, pushing the synchronizer sleeve to move and shift gears.

[0009] Furthermore, the upper and lower friction surfaces of the metal sleeve are connected to the side surfaces to extend a side guard; the side guard clamps the end of the fork.

[0010] Furthermore, an anti-slip groove is formed at the end of the shift fork, and the anti-slip groove is engaged with the upper end protrusion and the lower end protrusion.

[0011] Furthermore, the end of the shift fork is also provided with an anti-deflection chamfer, and the anti-deflection chamfer is engaged with the side retaining edge.

[0012] Furthermore, the shift fork assembly is used to be slidably connected to the shaft hole of the transmission case through the upper end of the fork shaft and the lower end of the fork shaft on the fork shaft.

[0013] Furthermore, the metal sleeve is made of spring steel material through heat treatment.

[0014] The beneficial technical effect of the present invention is as follows: when shifting, the shift fork assembly moves, driving the shift fork to move, so that the friction surfaces of the upper and lower parts of the metal sleeve contact the upper and lower surfaces of the tooth sleeve groove on the synchronizer tooth sleeve, and the synchronizer tooth sleeve is pushed to move and shift. Due to the high-speed rotation of the synchronizer tooth sleeve, accompanied by the inevitable deflection of the synchronizer tooth sleeve around the central axis, the upper and lower surfaces of the tooth sleeve groove will continuously knock and unbalance the friction surfaces of the upper and lower parts. The metal sleeve is made of spring steel material through heat treatment, which can effectively prevent the cracking, crushing, falling off, and excessive wear of the plastic sleeve, and avoids the functional problems of the transmission hitting the gear and disengaging due to the shift fork damage. The upper and lower protrusions of the metal sleeve and the side ribs firmly clamp the end of the shift fork, ensuring the firm clamping fit of the end of the shift fork during the shifting process. The friction surfaces of the upper and lower parts also contact and fit closely with the upper and lower surfaces of the tooth sleeve groove, ensuring smooth and high-quality shifting. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of a transmission shift fork mechanism in the prior art;

[0016] Figure 2 It is a schematic diagram of the structure of a transmission shift fork assembly in the prior art;

[0017] Figure 3 It is a schematic diagram of a transmission shift fork in the prior art;

[0018] Figure 4 It is a schematic diagram of a plastic sleeve in the prior art;

[0019] Figure 5 It is a schematic diagram of the transmission shift fork mechanism of the present invention;

[0020] Figure 6 It is a schematic diagram of the transmission shift fork assembly of the present invention;

[0021] Figure 7 A schematic diagram of a transmission shift fork of the present invention;

[0022] Figure 8 It is a schematic diagram of the metal sleeve of the present invention. DETAILED DESCRIPTION

[0023] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0024] The present invention discloses a transmission shift fork mechanism, including a shift fork assembly 1 and a synchronizer assembly 2. The shift fork assembly 1 includes a shift fork shaft 12, a shift fork connecting sleeve 13 and a shift fork 14. The shift fork 14 of the shift fork assembly 1 is fixedly connected to the shift fork shaft 12 through the shift fork connecting sleeve 13. The end of the shift fork 14 is sleeved with a metal sleeve 141; the metal sleeve 141 is composed of two upper and lower friction surfaces 1411. The end of the upper friction surface 1411 is an upper end protrusion 1413, and the end of the lower friction surface 1411 is a lower end protrusion 1414. The upper and lower friction surfaces 1411 of the metal sleeve 141 are connected to the side to extend the side retaining edge 1412.

[0025] An anti-slip groove 142 is provided at the end of the fork 14, which cooperates with the upper end protrusion 1413 and the lower end protrusion 1414 to prevent the metal sleeve 141 from slipping out; an anti-deflection chamfer 143 is also provided at the end of the fork 14, which cooperates with the side retaining edge 1412 to prevent the metal sleeve 141 from swinging left and right.

[0026] The outer ring side wall of the synchronizer gear sleeve 21 of the synchronizer assembly 2 is circumferentially provided with a gear sleeve groove 211;

[0027] During operation, the shift fork assembly 1 moves, driving the shift fork 14 to move, so that the upper friction surface 1411 and the lower friction surface 1411 of the metal sleeve 141 contact the upper and lower surfaces of the sleeve groove 211 on the synchronizer sleeve 21, pushing the synchronizer sleeve 21 to move and shift.

[0028] The shift fork assembly 1 is slidably connected to the shaft hole of the transmission case through the fork shaft upper end 122 and the fork shaft lower end 121 on the fork shaft 12 .

[0029] The metal sleeve 141 is made of spring steel material through heat treatment.

[0030] A transmission shift fork mechanism adopting this structure is used for shifting in driving state. The shift fork assembly 1 moves, driving the shift fork 14 to move, so that the friction surfaces 1411 of the upper and lower parts of the metal sleeve 141 contact the upper and lower surfaces of the tooth sleeve groove 211 on the synchronizer tooth sleeve 21, and the synchronizer tooth sleeve 21 is pushed to move and shift. Since the synchronizer tooth sleeve 21 rotates at a high speed, accompanied by the inevitable deflection of the synchronizer tooth sleeve 21 around the central axis, the upper and lower surfaces of the tooth sleeve groove 211 will be constantly knocked and the upper and lower friction surfaces 1411 will be squeezed unbalancedly. Since the metal sleeve 141 is made of spring steel material through heat treatment, it can effectively prevent the cracking, crushing, shedding, excessive wear and other problems of the plastic sleeve, avoid the functional problems of the transmission hitting teeth and disengaging caused by the synchronizer tooth sleeve 21 shifting stroke not being in place due to the damage of the shift fork, and improve the shifting quality of the transmission. At the same time, the plastic sleeve injection molding material utilization rate is low, pollutes the environment, and has low parts molding efficiency, while the metal sleeve 141 can be stamped by spring steel sheet, with less material consumption, fast molding, high efficiency and low cost, thereby reducing production costs.

Claims

1. A transmission shift fork mechanism, characterized in that: It includes a shift fork assembly (1) and a synchronizer assembly (2); The shift fork assembly (1) comprises a shift fork shaft (12), a shift fork connecting sleeve (13) and a shift fork (14); the shift fork (14) of the shift fork assembly (1) is fixedly connected to the shift fork shaft (12) via the shift fork connecting sleeve (13); the end of the shift fork (14) is sleeved with a metal sleeve (141); the metal sleeve (141) is composed of two upper and lower friction surfaces (1411); the end of the upper friction surface (1411) is an upper end protrusion (1413), and the end of the lower friction surface (1411) is a lower end protrusion (1414); the upper end protrusion (1413) and the lower end protrusion (1414) are connected to each other. The protrusions (1414) face each other and fix the end of the shift fork (14); the upper and lower friction surfaces (1411) of the metal sleeve (141) are connected to the side to extend a side retaining edge (1412); the side retaining edge (1412) retains the end of the shift fork (14); the end of the shift fork (14) is provided with an anti-slip groove (142); the anti-slip groove (142) is engaged with the upper protrusion (1413) and the lower protrusion (1414); the end of the shift fork (14) is also provided with an anti-deflection chamfer (143); the anti-deflection chamfer (143) is engaged with the side retaining edge (1412); The outer ring side wall of the synchronizer sleeve (21) of the synchronizer assembly (2) is circumferentially provided with a sleeve groove (211); During operation, the shift fork assembly (1) moves, driving the shift fork (14) to move, causing the upper and lower friction surfaces (1411) of the metal sleeve (141) to contact the upper and lower surfaces of the sleeve groove (211) on the synchronizer sleeve (21), thereby pushing the synchronizer sleeve (21) to move and shift gears.

2. A transmission shift fork mechanism according to claim 1, characterized in that: The shift fork assembly (1) is used to be slidably connected to the shaft hole of the transmission case through the shift fork shaft upper end (122) and the shift fork shaft lower end (121) on the shift fork shaft (12).

3. A transmission shift fork mechanism according to claim 1, characterized in that: The metal sleeve (141) is made of spring steel material through heat treatment.

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