transmission

Abstract

The present invention relates to the technical field of transmission systems, particularly to transmissions, and includes a box-type transmission and a shift operating system, wherein the box-type transmission includes a housing, a main shaft, a counter shaft, a main shaft gear, a counter shaft gear, and a ratchet, and the shift operating system includes an elastic fork mechanism, a shift guide groove drum bar for moving and driving the elastic fork mechanism, a shift operating gear group for rotating the shift guide groove drum bar, and a shift control mechanism for rotating the shift operating gear group, the shift guide groove drum bar being rotatably mounted on the housing. The present invention employs a rotatable connection between the fork arm and the fork seat, which reduces friction, makes gear engagement and disengagement more flexible, extends the service life of the elastic member, and effectively avoids damage to the ratchet teeth due to tooth contact, sticking, or excessive pulling between the ratchet and the gear, thereby effectively extending the service life of the elastic member, the shift operating system, and the transmission.

Description

Technical Field

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[0001] The present invention relates to the technical field of transmission systems, and particularly refers to a transmission.

Background Art

[0002] In a transmission system, in order to realize a transmission change mechanism between different gear pairs of a transmission, it is necessary to shift using a shift operation system. Most of the existing shift forks of shift operation systems adopt a rigid mechanism. When the fork drives a ratchet to mesh with a gear and engage it into the gear, the ratchet teeth on the end faces of the ratchet and the gear strongly abut against each other, and tooth impact or stacking is likely to occur. When the ratchet disengages from the gear, damage to the ratchet teeth is likely to occur due to forcibly pulling the ratchet.

[0003] Chinese Invention Patent Application Publication No. CN115195932A discloses a bicycle bottom bracket transmission with load shifting. Here, one elastic notch and one elastic piece are installed on the fork, and a shift operation mechanism is disclosed that utilizes the repeated repulsive deformation force of the elastic piece to realize the performance that the fork has elasticity. During the use process of this fork structure, the elastic piece not only needs to exert a reciprocating deformation effect, but also needs to exert a certain connection and support effect. The elastic piece is likely to fatigue and fail early, still causing tooth impact or stacking phenomena between the ratchet and the gear, and also causing the service life of the transmission or the transmission to be shortened.

[0004] Based on the deficiencies of the above existing shift operation systems adopting rigid forks and elastic forks, it is necessary to provide a solution to overcome the above technical problems.

Summary of the Invention

Problems to be Solved by the Invention

[0005] This invention provides a transmission that addresses the shortcomings of conventional technology. Its shift fork employs a rotatable connection between the fork arm and the fork seat, resulting in less friction, more flexible gear engagement and disengagement, a longer service life for the elastic components, and effectively avoids damage to the ratchet caused by ratchet-gear tooth contact, jamming, or forceful pulling. [Means for solving the problem]

[0006] To solve the above technical problems, the present invention employs the following technical solutions.

[0007] The present invention provides a transmission including a box-type transmission and a shift operation system, the box-type transmission including a housing, a main shaft and a sub-shaft mounted in parallel to the housing, the main shaft having at least one main shaft gear attached, the sub-shaft having a sub-shaft gear that meshes with the main shaft gear, the main shaft having a ratchet that meshes with the main shaft gear slide-mounted to it, and / or the sub-shaft having a ratchet that meshes with the sub-shaft gear, the ratchet being driven and connected to the shift operation system, The shift operation system includes an elastic fork mechanism, a shift guide groove drum rod for moving the elastic fork mechanism, a shift operation gear group for rotationally driving the shift guide groove drum rod, and a shift control mechanism for rotationally driving the shift operation gear group, wherein the shift guide groove drum rod is rotatably mounted to the housing. The elastic fork mechanism includes a fork seat, a fork arm rotatably connected to the fork seat, and an elastic member for resetting the fork arm, wherein when the fork arm swings relative to the fork seat, the elastic member drives the fork arm to reset. A shift guide groove is provided on the circumferential surface of the shift guide groove drum rod, a fork protrusion is provided on the upper end of the fork seat, the fork protrusion is movably installed within the shift guide groove, and the lower end of the fork arm is movably connected to a ratchet.

[0008] Here, the box-type transmission further includes a chain wheel attached to the main shaft and cranks attached to both ends of the main shaft. A lower fork section is installed on the fork arm, and a pull-out peg is installed on the inside of both ends of the lower fork section, and the pull-out peg is movably installed in the fork groove on the circumferential surface of the ratchet.

[0009] Here, two slide guide holes are arranged in parallel on the upper part of the fork seat, the fork seat is fitted onto two guide rods using the slide guide holes, and the two guide rods are attached to the housing.

[0010] Preferably, a mounting groove is provided at the lower part of the fork seat, a fork arm connection part is provided on the fork arm, and the fork arm connection part is attached to the mounting groove using a fork arm rotation axis. The elastic member is a torsion spring, the spring body of which is attached to the fork arm rotation axis, and the output end head of the torsion spring clamps the fork arm connection and the fork seat.

[0011] Here, a storage groove is provided in the fork arm connection portion, the fork arm rotation shaft passes through the storage groove, the spring body of the torsion spring is attached to the storage groove, and the output end head extends out of the storage groove before clamping the fork seat.

[0012] Here, the shift operation gear group is mounted on a housing, and the shift operation gear group includes a shift operation driven gear mounted on a shift guide groove drum rod and a shift operation drive gear that meshes with the shift operation driven gear. A return coil spring for resetting the gear is installed on one side of the shift operation drive gear, one end of the return coil spring is connected to the gear wall of the shift operation drive gear, and the other end of the return coil spring is connected to the mounting shaft of the shift operation drive gear.

[0013] Here, the shift control mechanism includes a shift wire, a wire adjustment mechanism, and a wire controller. A wire mounting groove is provided on the shift operation drive gear, one end of the shift wire is routed around the wire mounting groove, and the other end of the shift wire passes through the wire adjustment mechanism before entering the wire controller.

[0014] Here, the wire adjustment mechanism includes a mounting base installed on the transmission housing, an adjustment screw connected to the mounting base, and a lock nut connected to the adjustment screw. The mounting base is provided with a seat screw hole, the seat screw hole communicates with the inside of the transmission housing, the adjustment screw has a hollow structure, and the adjustment screw has an adjustment screw segment. The adjustment screw segment is screwed into the seat screw hole, the lock nut is fitted onto the adjustment screw segment and screwed into the adjustment screw segment, and the elastic fork mechanism, shift guide groove drum rod, and shift operation gear group are all installed inside the transmission housing.

[0015] Here, the adjustment screw is further provided with a screw head portion that is connected to the adjustment screw segment, and the mounting seat and the transmission housing are integrally molded.

[0016] Here, the wire adjustment mechanism further includes a wire pipe, and a pipe recess is provided at one end of the screw head portion that is separated from the adjustment screw segment, and one end of the wire pipe is attached to the pipe recess. [Effects of the Invention]

[0017] The beneficial effects of the present invention are as follows:

[0018] (1) The present invention adopts a rotatable connection between the fork arm and the fork sheet. When the fork arm swings relative to the fork sheet, the elastic member always drives the fork arm to reset, enabling the fork structure to have elasticity. When the elastic fork mechanism drives the ratchet to engage with the main shaft gear or the countershaft gear, it has the effect of releasing force, thereby avoiding tooth impact or stacking caused by the strong abutment of the ratchet teeth on the end faces of the main shaft gear or the countershaft gear. When the ratchet disengages from the main shaft gear or the countershaft gear, damage to the ratchet teeth can be avoided by forcibly pulling the ratchet.

[0019] (2) The present invention adopts a rotatable connection between the fork arm and the fork sheet, with low friction during the swinging of the fork arm, making the engagement and disengagement between the ratchet and the main shaft gear or the countershaft gear more flexible. When the fork arm swings relative to the fork sheet 1 at a small angle, a large displacement of the ratchet can be obtained. Compared with the displacement adopted by existing rigid forks and some elastic forks, not only is the damage small, but the service life is long. The elastic deformation of the elastic member is reduced, avoiding the early failure of the elastic member, and effectively extending the service life of the elastic member, the elastic fork mechanism, and the transmission.

Brief Description of the Drawings

[0020] [Figure 1] It is a three-dimensional structural schematic diagram of the present invention. [Figure 2] It is a three-dimensional structural schematic diagram of another perspective of the present invention. [Figure 3] It is a three-dimensional structural schematic diagram of the present invention after hiding the housing. [Figure 4] It is a three-dimensional structural schematic diagram of another perspective of the present invention after hiding the housing. [Figure 5] It is a structural schematic diagram of yet another perspective of the present invention after hiding the housing. [Figure 6] It is a three-dimensional structural schematic diagram of the shift operation system described in the present invention. [Figure 7]It is a three-dimensional structural schematic diagram of another perspective of the shift operation system described in the present invention. [Figure 8] It is a three-dimensional structural schematic diagram of the elastic fork mechanism described in the present invention. [Figure 9] It is an exploded structural schematic diagram of the elastic fork mechanism described in the present invention. [Figure 10] It is a three-dimensional structural schematic diagram of the elastic fork mechanism after the ratchet is installed as described in the present invention. [Figure 11] It is a three-dimensional structural schematic diagram of the shift operation system described in the present invention after hiding the shift operation gear group and the shift control mechanism. [Figure 12] It is an exploded structural schematic diagram of the shift control mechanism described in the present invention after hiding the wire controller. [Figure 13] It is a three-dimensional structural schematic diagram of the shift control mechanism described in the present invention after hiding the wire controller. [Figure 14] It is a three-dimensional structural schematic diagram of the adjusting screw described in the present invention. [Figure 15] It is a three-dimensional structural schematic diagram of another perspective of the present invention.

Embodiments for Carrying out the Invention

[0021] For the convenience of those skilled in the art, the present invention will be further described below with reference to embodiments and the accompanying drawings. However, the content mentioned in the embodiments does not limit the present invention. The present invention will be described in detail below with reference to the drawings.

[0022] Referring to FIGS. 1 to 15, a transmission including a box-type transmission device and a shift operation system, wherein the box-type transmission device includes a housing 400, a main shaft 05 and a countershaft 06 mounted in parallel on the housing 400. At least one main shaft gear 07 is mounted on the main shaft 05, and a countershaft gear 08 meshing with the main shaft gear 07 is mounted on the countershaft 06. A ratchet 01 meshing with the main shaft gear 07 is slidably mounted on the main shaft 05, and / or a ratchet 0 in meshing with the countershaft gear 08 is mounted on the countershaft 06. The ratchet 01 is driven and connected to the shift operation system. The shift operation system includes an elastic fork mechanism 5, a shift guide groove drum rod 6 for moving the elastic fork mechanism 5, a shift operation gear group 7 for rotationally driving the shift guide groove drum rod 6, and a shift control mechanism 8 for rotationally driving the shift operation gear group 7, wherein the shift guide groove drum rod 6 is rotatably mounted on the housing 400. The elastic fork mechanism 5 includes a fork seat 1, a fork arm 3 rotatably connected to the fork seat 1, and an elastic member 2 for resetting the fork arm 3. When the fork arm 3 swings relative to the fork seat 1, the elastic member 2 drives the fork arm 3 to reset it. A shift guide groove 61 is provided on the circumferential surface of the shift guide groove drum rod 6, a fork convex column 13 is provided on the upper end of the fork seat 1, the fork convex column 13 is movably installed within the shift guide groove 61, and the lower end of the fork arm 3 is movably connected to the ratchet 01.

[0023] Specifically, the elastic fork mechanism 5 and the shift guide groove 61 on the shift guide groove drum rod 6 may be installed one or more times as needed. The main shaft gear 07 and the sub-shaft gear 08 may be installed in multiple quantities as needed, and the main shaft gear 07 and the sub-shaft gear 08 may be installed in different sizes and series sizes as needed.

[0024] In actual application, the shift control mechanism 8 rotates the shift operation gear group 7, the shift operation gear group 7 rotates the shift guide groove drum rod 6, and the shift guide groove 61 drives the fork convex column 13 to move the elastic fork mechanism 5. During the movement of the elastic fork mechanism 5, if the ratchet of the ratchet 01 collides with the ratchet of the main shaft gear 07 or the sub-shaft gear 08, the fork arm 3 swings relative to the fork seat 1, and the elastic member 2 always drives the fork arm 3 to reset the ratchet 01. The deformation of the elastic member 2 provides the elastic fork mechanism 5 with a retraction action, avoiding gearing and jamming, thereby engaging the ratchet 01 with the main shaft gear 07 or the sub-shaft gear 08 and achieving shifting.

[0025] The present invention employs a rotatable connection between the fork arm 3 and the fork seat 1. When the fork arm 3 swings relative to the fork seat 1, the elastic member 2 always drives and resets the fork arm 3, thereby providing elasticity to the fork structure. The elastic fork mechanism 5 has the effect of releasing the force when the ratchet 01 is driven to engage with the main shaft gear 07 or sub-shaft gear 08. This prevents tooth strike or jamming caused by the ratchet teeth on the end faces of the ratchet 01 and the main shaft gear 07 or sub-shaft gear 08 strongly abutting against each other, and prevents damage to the ratchet teeth caused by forcibly pulling the ratchet 01 when it disengages from the main shaft gear 07 or sub-shaft gear 08.

[0026] This invention employs a rotatable connection between the fork arm 3 and the fork seat 1, resulting in less friction during the oscillation of the fork arm 3, making the engagement and disengagement of the ratchet 01 and the main shaft gear 07 or sub-shaft gear 08 more flexible. When the fork arm 3 oscillates at a small angle relative to the fork seat 1, a large displacement of the ratchet 01 can be obtained. Compared to the displacements used in existing rigid forks and some elastic forks, this not only results in less damage but also a longer service life. It reduces the elastic deformation of the elastic member 2, avoids premature failure of the elastic member 2, and effectively extends the service life of the elastic member 2, the elastic fork mechanism 5, and the transmission.

[0027] In this embodiment, two slide guide holes 11 are installed in parallel on the upper part of the fork seat 1, and the fork seat 1 is fitted onto two guide rods 03 using the slide guide holes 11, and the two guide rods 03 are attached to the housing. During operation, the fork seat 1 moves on the guide rods 03 by driving the entire elastic fork mechanism and the ratchet 01, thereby enabling the ratchet 01 to engage and disengage from the main shaft gear 07 or sub-shaft gear 08. Specifically, by installing two slide guide holes 11 in parallel, and having two slide guide holes 11 installed, and attaching the fork seat 1 to the two guide rods 03, adopting such a two-guide rod design effectively avoids shaking and reversal of the fork seat 1 and the entire elastic fork mechanism, stabilizing the structure of the transmission and ensuring reliable power transmission.

[0028] In this embodiment, a mounting groove 12 is provided at the lower part of the fork seat 1, a fork arm connection part 31 is provided on the fork arm 3, the fork arm connection part 31 is attached to the mounting groove 12 using a fork arm rotation shaft 4, the elastic member 2 is a torsion spring, the spring body 21 of the torsion spring is attached to the fork arm rotation shaft 4, and the output end head 22 of the torsion spring clamps the fork arm connection part 31 and the fork seat 1. Specifically, the fork arm connection part 31 is attached to the fork arm rotation shaft 4, both ends of the fork arm rotation shaft 4 are attached to the groove walls on both sides of the mounting groove 12, the fork arm connection part 31 is housed within the mounting groove 12, the structure is compact and provides high stability when the fork arm 3 rotates.

[0029] In this embodiment, a storage groove 311 is provided in the fork arm connection portion 31, the fork arm rotation shaft 4 passes through the storage groove 311, the spring body 21 of the torsion spring is attached to the storage groove 311, and the output end head 22 extends out of the storage groove 311 before clamping the fork seat 1. By attaching the spring body 21 of the torsion spring inside the storage groove 311, the torsion spring is attached and positioned, the structure is stabilized and the attachment is secure, and the elastic fork mechanism 5 is made more compact.

[0030] In this embodiment, a lower fork portion 32 is installed on the fork arm 3, and pull-out stakes 321 are installed on the inside of both ends of the lower fork portion 32, and the pull-out stakes 321 are movably installed in the fork groove 011 on the circumferential surface of the ratchet 01.

[0031] In this embodiment, the shift operation gear group 7 is mounted on the housing 400, and the shift operation gear group 7 includes a shift operation driven gear 71 attached to the shift guide groove drum rod 6 and a shift operation drive gear 72 that meshes with the shift operation driven gear 71. A return coil spring 73 for resetting the gear is installed on one side of the shift operation drive gear 72, one end of the return coil spring 73 is connected to the gear wall of the shift operation drive gear 72, and the other end of the return coil spring 73 is connected to the mounting shaft of the shift operation drive gear 72. Specifically, the shift control mechanism 8 includes a shift wire 81, a wire adjustment mechanism 82, and a wire controller. A wire mounting groove is installed on the shift operation drive gear 72, one end of the shift wire 81 is routed around the wire mounting groove, and the other end of the shift wire 81 passes through the wire adjustment mechanism 82 before entering the wire controller. The pull wire controller can be implemented using an existing controller structure, so it will not be described further.

[0032] In this embodiment, the wire adjustment mechanism 82 is used to adjust the slack of the shift wire 81. When a shift is required, the wire controller controls the shift wire 81 to rotate the shift operation drive gear 72, which in turn rotates the shift operation driven gear 71, thereby rotating the shift guide groove drum rod 6, moving the elastic fork mechanism 5 to engage the ratchet 01 with the gear 02, and thus achieving a shift. After the force that the shift wire 81 exerts on the shift operation drive gear 72 is released, the return coil spring 73 resets the shift operation drive gear 72.

[0033] This is to overcome the technical challenges of existing wire adjustment mechanisms being mounted on the frame, which makes it difficult to observe the slack state of the shift wire in the derailleur, making adjustment extremely inconvenient, and also the fact that the shift wire tends to loosen during use even after adjustment. The present invention further provides a wire adjustment mechanism 82 which includes a mounting seat 100 installed on a transmission housing 400, an adjustment screw 200 connected to the mounting seat 100, and a lock nut 300 connected to the adjustment screw 200, wherein a seat screw hole 101 is provided in the mounting seat 100 and the seat screw hole 101 communicates with the inside of the transmission housing 400, the adjustment screw 200 has a hollow structure and an adjustment screw segment 201 is provided on the adjustment screw 200 and the adjustment screw segment 201 is screwed into the seat screw hole 101, the lock nut 300 is fitted onto the adjustment screw segment 201 and screwed onto the adjustment screw segment 201, and the elastic fork mechanism 5, the shift guide groove drum rod 6, and the shift operating gear group 7 are all installed inside the transmission housing 400.

[0034] In actual application, one end of the shift wire 81 is routed around the shift operation drive gear 72, and the other end of the shift wire 81 passes sequentially through the mounting seat 100 and the adjustment screw 200 before being connected to the wire controller on the frame's side handle. Immediately after mounting the shift wire 81, it is still loose. In this case, the adjustment screw 200 and the lock nut 300 on the adjustment screw segment 201 are twisted simultaneously to shorten the threaded segment between the mounting seat 100's screw hole 101 and the adjustment screw segment 201, increasing the length of the adjustment screw segment 201 exposed from the screw hole 101, i.e., increasing the length of the adjustment screw segment 201 to accommodate the shift wire 81 in a sleeve connection, thereby tensioning the shift wire 81. After the shift wire 81 is tensioned, the adjustment screw segment 201 is twisted independently to bring its end face into contact with the mounting seat 100. In this case, the adjustment screw 200 is less likely to be screwed into the mounting seat 100's screw hole 101 on its own, thereby enabling locking after the shift wire 81 has been tensioned.

[0035] This wire adjustment mechanism 82 adopts the installation of the mounting base 100 on the derailleur housing 400, facilitating the installation of parts such as the adjustment screw 200 and lock nut 300. It does not require installation on other locations such as the bicycle frame, making installation easy, while also effectively utilizing the mounting position, saving other mounting space, and ensuring a secure and stable structure.

[0036] This wire adjustment mechanism 82 allows for real-time observation of the slack state of the shift wire 81 in the shift operation drive gear 72 when the mounting seat 100 is installed on the transmission housing 400 and the slack of the shift wire 81 is adjusted by twisting the adjustment screw segment 201 and the lock nut 300. Compared to existing wire adjustment devices, it effectively increases the convenience and efficiency of adjusting the shift wire 81, thereby improving the overall assembly efficiency of transmission products and reducing labor costs.

[0037] This wire adjustment mechanism 82 adjusts the looseness or tightness of the shift wire 81 by shortening or increasing the screw length between the adjustment screw 200 and the mounting seat 100. The operation is simple, requiring only twisting the adjustment screw 200 forward or backward, making it easy for the operator to start working. At the same time, the shift wire 81 is locked using the lock nut 300, which prevents the shift wire 81 from loosening during use, improving the reliability of the shift control of the gear shifting mechanism and improving the overall quality of the gear shift product.

[0038] In this embodiment, the adjustment screw 200 is further provided with a screw head portion 202 connected to the adjustment screw segment 201, making screw adjustment easy and facilitating the attachment of other components such as the wire pipe 500. The mounting seat 100 and the transmission housing 400 are integrally molded structures. Specifically, by processing and molding the mounting seat 100 and the transmission housing 400 together, the individual processing of parts is reduced, avoiding the complicated process of assembling multiple parts after processing them, as well as facilitating the attachment of parts and making the structure more stable after attachment.

[0039] In this embodiment, the wire adjustment mechanism 82 further includes a wire pipe 500, and a pipe recess 203 is provided at one end of the screw head portion 202 away from the adjustment screw segment 201, and one end of the wire pipe 500 is attached to the pipe recess 203. The use of the pipe recess 203 allows for storage, attachment, and positioning of the wire pipe 500, which is advantageous for threading and tensioning the shift wire 81.

[0040] The above descriptions are merely preferred embodiments of the present invention and do not imply any formal limitation of the present invention. The present invention is disclosed as described above in the preferred embodiments, but is not intended to limit the present invention. Those skilled in the art will know that equivalent embodiments modified by some modifications or equivalent changes using the above disclosed technical content without departing from the technical solutions of the present invention, any simple modifications, equivalent changes and modifications made to the above embodiments, without departing from the technical solutions of the present invention, all fall within the scope of the technical solutions of the present invention.

Claims

1. A transmission including a box-type transmission and a shift operation system, wherein the box-type transmission includes a housing (400), a main shaft (05) and a sub-shaft (06) mounted in parallel to the housing (400), the main shaft (05) having at least one main shaft gear (07), the sub-shaft (06) having a sub-shaft gear (08) that meshes with the main shaft gear (07), the main shaft (05) having a sliding ratchet (01) that meshes with the main shaft gear (07), and / or the sub-shaft (06) having a ratchet (01) that meshes with the sub-shaft gear (08), and the ratchet (01) is driven and connected to the shift operation system. The shift operation system includes an elastic fork mechanism (5), a shift guide groove drum rod (6) for moving the elastic fork mechanism (5), a shift operation gear group (7) for rotationally driving the shift guide groove drum rod (6), and a shift control mechanism (8) for rotationally driving the shift operation gear group (7), wherein the shift guide groove drum rod (6) is rotatably mounted on the housing (400). The elastic fork mechanism (5) includes a fork seat (1), a fork arm (3) rotatably connected to the fork seat (1), and an elastic member (2) for resetting the fork arm (3). When the fork arm (3) swings relative to the fork seat (1), the elastic member (2) drives the fork arm (3) to reset it. A shift guide groove (61) is provided on the circumferential surface of the shift guide groove drum rod (6), a fork protrusion (13) is provided at the upper end of the fork seat (1), the fork protrusion (13) is movably installed within the shift guide groove (61), and the lower end of the fork arm (3) is movably connected to the ratchet (01). A mounting groove (12) is provided at the lower part of the fork seat (1), a fork arm connecting part (31) is provided on the fork arm (3), and the fork arm connecting part (31) is attached to the mounting groove (12) using a fork arm rotation axis (4). The transmission is characterized in that the elastic member (2) is a torsion spring, the spring body (21) of the torsion spring is attached to the fork arm rotation shaft (4), and the output end head (22) of the torsion spring clamps the fork arm connection part (31) and the fork seat (1).

2. The box-type transmission further includes a chain wheel (09) attached to the main shaft (05) and cranks (600) attached to both ends of the main shaft (05). The transmission according to claim 1, characterized in that a lower fork portion (32) is installed on the fork arm (3), pull-out pegs (321) are installed on the inside of both ends of the lower fork portion (32), and the pull-out pegs (321) are movably installed in the fork groove (011) on the circumferential surface of the ratchet (01).

3. The transmission according to claim 1, characterized in that two slide guide holes (11) are arranged in parallel on the upper part of the fork seat (1), the fork seat (1) is fitted onto two guide rods (03) using the slide guide holes (11), and the two guide rods (03) are attached to a housing (400).

4. The transmission according to claim 1, characterized in that a storage groove (311) is provided in the fork arm connection portion (31), the fork arm rotation shaft (4) passes through the storage groove (311), the spring body (21) of the torsion spring is attached to the storage groove (311), and the output end head (22) clamps the fork seat (1) after protruding from the storage groove (311).

5. The transmission according to claim 1, characterized in that the shift operation gear group (7) is mounted on a housing (400), and the shift operation gear group (7) includes a shift operation driven gear (71) attached to a shift guide groove drum rod (6) and a shift operation drive gear (72) that meshes with the shift operation driven gear (71), and a return coil spring (73) for resetting the gear is installed on one side of the shift operation drive gear (72), one end of the return coil spring (73) is connected to the gear wall of the shift operation drive gear (72), and the other end of the return coil spring (73) is connected to the mounting shaft of the shift operation drive gear (72).

6. The transmission according to claim 5, wherein the shift control mechanism (8) includes a shift wire (81), a wire adjustment mechanism (82), and a wire controller, and a wire mounting groove is provided on the shift operation drive gear (72), one end of the shift wire (81) is routed around the wire mounting groove, and the other end of the shift wire (81) passes through the wire adjustment mechanism (82) and then enters the wire controller.

7. The wire adjustment mechanism (82) includes a mounting base (100) installed on the transmission housing (400), an adjustment screw (200) connected to the mounting base (100), and a lock nut (300) connected to the adjustment screw (200). A seat screw hole (101) is provided in the mounting seat (100), the seat screw hole (101) communicates with the inside of the transmission housing (400), the adjustment screw (200) has a hollow structure, and an adjustment screw segment (201) is provided on the adjustment screw (200), The adjustment screw segment (201) is screwed into the seat screw hole (101), and the lock nut (300) is fitted onto the adjustment screw segment (201) and screwed onto the adjustment screw segment (201). The transmission according to claim 6, characterized in that the elastic fork mechanism (5), the shift guide groove drum rod (6), and the shift operation gear group (7) are all installed within the transmission housing (400).

8. The transmission according to claim 7, characterized in that the adjustment screw (200) is further provided with a screw head portion (202) connected to an adjustment screw segment (201), and the mounting seat (100) and the transmission housing (400) are integrally molded.

9. The gear shift according to claim 8, wherein the wire adjustment mechanism (82) further includes a wire pipe (500), and a pipe recess (203) is provided at one end of the screw head portion (202) away from the adjustment screw segment (201), and one end of the wire pipe (500) is attached to the pipe recess (203).

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