CN206694510U - A kind of more gear rotating speed change gears of twin shaft - Google Patents

Abstract

A two-shaft multi-gear forward and reverse speed change device, including a box body and a first rotating shaft and a second rotating shaft installed side by side, and also includes a straight bevel gear, a reverse bevel gear, an input bevel gear and the second rotating shaft A plurality of power input gears, the first rotating shaft is provided with a gear shift assembly that can be engaged with any one of the plurality of power input gears or not meshed by switching, and the bevel gear for straight travel is fixedly installed on the first rotating shaft. The reverse bevel gear is rotatably sleeved on the first rotating shaft. The straight bevel gear and the reverse bevel gear are respectively arranged on both sides of the input bevel gear and both mesh with the input bevel gear. The reverse bevel gear is slidingly provided with multiple At least one of the power input gears engages or none of the reverse gears engages, and the multi-gear forward and reverse conversion mechanism further includes a reverse shift fork assembly for driving the reverse gear to slide. It has the advantages of less number of shafts and gears, compact structure, light weight, low cost, convenient installation, wide application range and the like.

Description

A double-shaft multi-gear forward and reverse transmission device

technical field

The utility model relates to the technical field of transmission devices, in particular to a biaxial multi-gear forward and reverse transmission device.

Background technique

At present, the gearboxes of crawler tractors on the market generally do not have the function of in-situ steering. The gearboxes of crawler tractors usually adopt the design of hydraulic pump motor and mechanical shifting to realize a wide range of adjustable driving speeds, and there are many gears and shafts. , The system is complex, the cost is high, the gearbox size is too large, the failure rate is high, the operation is inconvenient, and the adaptability is not strong. Moreover, some of the rear axles of crawler tractor gearboxes on the market do not have the in-situ steering function. Although the rear axles of some gearboxes have steering functions, their structures are complicated, the installation accuracy is high, and the difficulty is great, making the existence of the gearbox unavoidable. Disadvantages such as high cost and large rear axle space. In addition, the shift mechanism of the crawler tractor gearbox on the market generally uses three or more shafts to achieve multiple forward and reverse gears. The large number of gears and shafts directly leads to the complexity of the transmission system, high cost, and overall problems such as large size and low reliability.

Utility model content

The technical problem to be solved by the utility model is to overcome the deficiencies of the prior art, and provide a biaxial multi-gear positive and negative transformation with few shafts and gears, compact structure, light weight, low cost, convenient installation and wide adaptability speed device.

In order to solve the above technical problems, the utility model adopts the following technical solutions:

A two-shaft multi-gear forward and reverse transmission device, including a box body and a first rotating shaft and a second rotating shaft installed side by side in the box body, and a multi-gear forward and reverse gear is arranged between the first rotating shaft and the second rotating shaft. Rotation conversion mechanism, the multi-gear forward and reverse conversion mechanism includes a straight bevel gear, a reverse bevel gear, an input bevel gear connected to the power source, and a plurality of power input gears installed on the second rotating shaft. A rotating shaft is provided with a gear-type shifting assembly that can mesh with any one of a plurality of power input gears or not mesh with a plurality of power input gears through conversion, and the straight travel gear bevel gear is fixedly installed on the first rotating shaft. The reverse bevel gear is rotatably sleeved on the first rotating shaft, the straight bevel gear and the reverse bevel gear are respectively arranged on both sides of the input bevel gear and both mesh with the input bevel gear, and the reverse bevel gear is Slidingly provided with a reverse gear that can be engaged with at least one of the multiple power input gears or not meshed with multiple power input gears through sliding, and the multi-speed forward and reverse conversion mechanism also includes a gear for driving the reverse gear Sliding reverse gear fork assembly.

In the above biaxial multi-gear forward and reverse transmission device, preferably, the plurality of power input gears are first gear, second gear, third gear and fourth gear, and the first gear, second gear, third gear The shift gear and the fourth gear are fixedly installed on the second rotating shaft, and the gear shift assembly includes a first shift dual gear and a second shift dual gear, and the first shift dual gear is slidably arranged on On the first rotating shaft, one can be engaged with the first gear and the second gear by sliding or not meshed with the first gear and the second gear. By sliding, one of the third gear and the fourth gear is engaged or neither is engaged with the third gear and the fourth gear. A row shift fork assembly and a second straight travel shift fork assembly for driving the second shift dual gear to slide.

For the above-mentioned biaxial multi-gear forward and reverse transmission device, preferably, the first straight-travel gear fork assembly, the second straight-travel gear fork assembly and the reverse gear fork assembly all include a shift fork and are slidably arranged in the case The shift shaft on the top, the shift fork is fixed on the shift shaft, and the shift shaft is connected with a sliding drive member.

In the above-mentioned dual-shaft multi-gear forward and reverse transmission device, preferably, an independent shift shaft is provided for each of the first straight-shift fork assembly, the second straight-shift fork assembly, and the reverse shift fork assembly.

For the above-mentioned two-axis multi-gear forward and reverse transmission device, preferably, the shift shaft is slidably arranged in a sliding seat fixed on the casing, and a shifting shaft is also arranged between the shift shaft and the sliding seat. Elastic positioning components.

In the above biaxial multi-gear forward and reverse transmission device, preferably, the shift elastic positioning assembly includes a pressing steel ball and a compression spring, the sliding seat is provided with a counterbore opening facing the shift shaft, the compression spring and the compression spring Tightening steel balls are installed in the counterbore in turn, and the compression spring makes the compression steel balls close to the shift shaft, and the shift shaft is provided with a plurality of positioning counterbores for pressing the compression steel balls.

For the above-mentioned dual-shaft multi-gear forward and reverse transmission device, preferably, the first shifting dual gear, the second shifting dual gear and the reverse bevel gear are all provided with slots, and the first shifting The shift forks corresponding to the dual gear, the second gear shift dual gear and the reverse bevel gear are provided with U-shaped clips that are clipped in the clip slots.

In the above-mentioned two-shaft multi-gear forward and reverse transmission device, preferably, a power output gear is fixedly installed on the second rotating shaft.

Compared with the prior art, the utility model has the advantages that: in the biaxial multi-gear forward and reverse transmission device of the utility model, the bevel gear for the straight travel gear and the bevel gear for the reverse gear adopt a coaxial design, and respectively carry out forward gear and reverse gear. The power transmission of the reverse gear greatly simplifies the reverse gear mechanism, reduces the number of shafts and gears, improves the compactness of the structure and reduces the cost; moreover, two bevel gears, the straight bevel gear and the reverse bevel gear, are used with the input The bevel gear meshing can better balance the axial force generated by the bevel gear meshing transmission and reduce the axial serial movement of the first rotating shaft; The device has the advantages of small number of shafts and gears, simple and compact structure, light weight, wide range of speed adaptation, low manufacturing cost, convenient installation, etc., and can be widely used in the transmission system of crawler tractors.

Description of drawings

Fig. 1 is a partial cross-sectional view of a biaxial multi-gear forward and reverse transmission device.

Fig. 2 is a partial cross-sectional view of the first straight-travel gear fork assembly, the second straight-travel gear fork assembly, and the reverse gear fork assembly respectively cooperating with the first shifting dual gear, the second shifting dual gear, and the reverse gear .

Fig. 3 is a schematic diagram of the installation structure of the first straight-travel gear fork assembly, the second straight-travel gear fork assembly and the reverse gear fork assembly.

illustration:

100, box body; 501, first rotating shaft; 502, second rotating shaft; 503, first gear; 504, second gear; 505, third gear; 506, fourth gear; 507, first shift double gear ; 508, the second gear shift double gear; 509, the bevel gear of the straight travel gear; 510, the bevel gear of the reverse gear; 511, the input bevel gear; 512, the reverse gear; 515, reverse gear shift fork assembly; 521, shift fork; 522, shift shaft; 601, power output gear.

detailed description

Below in conjunction with accompanying drawing and specific embodiment the utility model is described in further detail.

As shown in Figures 1 to 3, the biaxial multi-gear forward and reverse transmission device of this embodiment includes a casing 100 and a first rotating shaft 501 and a second rotating shaft 502 installed side by side in the casing 100, the first rotating shaft Between 501 and the second rotating shaft 502, a multi-gear forward and reverse conversion mechanism is provided, and the multi-gear forward and reverse conversion mechanism includes a straight bevel gear 509, a reverse bevel gear 510, an input bevel gear 511 connected to the power source, and A plurality of power input gears installed on the second rotating shaft 502, the first rotating shaft 501 is provided with a gear shift gear that can be engaged with any one of the plurality of power input gears or not meshed with the plurality of power input gears through conversion Assemblies, the straight bevel gear 509 is fixedly installed on the first rotating shaft 501, the reverse bevel gear 510 is rotatably sleeved on the first rotating shaft 501, the straight bevel gear 509 and the reverse bevel gear 510 are separately arranged on the input bevel gear 511 Both sides are meshed with the input bevel gear 511. The reverse gear 510 is slidably provided with a reverse gear 512. The reverse gear 512 can be engaged with at least one of a plurality of power input gears by sliding or with a plurality of power input gears. Both are not meshed, and the multi-gear forward and reverse conversion mechanism also includes a reverse gear fork assembly 515 for driving the reverse gear 512 to slide.

In this embodiment, the plurality of power input gears are the first gear 503, the second gear 504, the third gear 505 and the fourth gear 506, the first gear 503, the second gear 504, the third gear 505 and the fourth gear 506 are fixedly installed on the second rotating shaft 502 at intervals along the axial direction. The gear shift assembly includes a first shifting dual gear 507 and a second shifting dual gear 508. The first shifting dual gear 507 is axially Slidingly arranged on the first rotating shaft 501, the first shifting dual gear 507 can choose one to mesh with any one of the first gear 503 and the second gear 504 by sliding, or it can not mesh with the first gear 503 and the second gear 504. meshing, the second shifting dual gear 508 is slid on the first rotating shaft 501 in the axial direction, and the second shifting dual gear 508 can mesh with any one of the third gear 505 and the fourth gear 506 by sliding Or it does not mesh with the third gear 505 and the fourth gear 506. The gear shift assembly also includes the first straight shift fork assembly 513 for driving the first shifting dual gear 507 to slide and the second for driving the second gear. The shifting dual gear 508 slides the second straight travel shift fork assembly 514 . In this embodiment, the reverse gear 512 is set to only mesh or not mesh with the second gear 504 by sliding, so as to transmit or not transmit the power of the first rotating shaft 501 to the second rotating shaft 502 through the reverse gear 512, that is, reverse The blocking gear 512 only has two states through sliding, the first state is meshing with the second speed gear 504 , and the second state is not meshing with the second speed gear 504 . In other embodiments, the reverse gear 512 can also be set to cooperate with one of the first gear 503, the third gear 505 and the fourth gear 506 for transmission or non-transmission; or with the first gear 503, the second gear 504 1. Two or more of the third gear 505 and the fourth gear 506 cooperate.

Both ends of the first rotating shaft 501 and the second rotating shaft 502 of this embodiment are respectively installed on the box body 100 through a bearing assembly, the bearing assembly includes a bearing and an end cover fixedly installed on the box body 100, the first rotating shaft 501 and the second The rotating shaft 502 is installed in the end cover through bearings, and sealing rings are provided between the first rotating shaft 501 and the second rotating shaft 502 and the end cover. The first shifting dual gear 507 and the second shifting dual gear 508 cooperate with the first rotating shaft 501 through splines, and can slide along the first rotating shaft 501; the reverse gear bevel gear 510 is rotatably sleeved and installed on the second rotating shaft 502, its axial ends are limited by the semi-circular retaining ring and shaft shoulder on the second rotating shaft 502 respectively, and the reverse gear 512 is installed on the reverse bevel gear 510 through spline fit, which can be used on the reverse bevel gear 510 slides axially along the second rotating shaft 502; the straight bevel gear 509 is mounted on the second rotating shaft 502 through spline fit, and it is composed of the axial component force when the input bevel gear 511 cooperates with the first rotating shaft 501 Axial positioning of the shaft shoulder. The first gear 503, the second gear 504, the third gear 505 and the fourth gear 506 are mounted on the second rotating shaft 502 through spline fit, and the first gear 503, the second gear 504, the third gear 505 and the fourth gear Between 506, an axial limit structure is used for axial positioning.

The multi-gear forward and reverse conversion mechanism can realize the conversion of the six forward gears, the forward second gear, the forward third gear, the forward fourth gear, the reverse gear and the neutral gear. When the gear of the first gear is forward, the first straight travel gear fork assembly 513 drives the first gear shift double gear 507 to slide until its large gear meshes with the first gear 503, and the second straight travel gear fork assembly 514 drives the second The gearshift dual gear 508 slides until it does not mesh with the third gear 505 and the fourth gear 506, the reverse gear shift fork assembly 515 drives the reverse gear 512 out of mesh with the second gear 504, and the power is input to the input bevel gear 511, It is then transmitted to the straight bevel gear 509 and the reverse bevel gear 510 through the input bevel gear 511. The straight bevel gear 509 and the reverse bevel gear 510 rotate under the drive of the input bevel gear 511. The steering of the two is opposite, and the reverse gear The bevel gear 510 idles on the first rotating shaft 501, and the straight bevel gear 509 rotates with the first rotating shaft 501 synchronously. The large gear of the shifting dual gear 507 and the first gear 503 are transmitted to the second rotating shaft 502 . The second gear forward is to change the sliding position of the first gear shifting dual gear 507 on the basis of the first forward gear, that is, the first straight forward gear shift fork assembly 513 drives the first gear shifting dual gear 507 to slide to its pinion and second gear. The gear 504 is meshed, and now the power of the input bevel gear 511 is transmitted to the second shaft 502 through the straight bevel gear 509, the first rotating shaft 501, the pinion of the first shifting dual gear 507, and the second gear 504. The third forward gear is to change the sliding positions of the first shifting dual gear 507 and the second shifting dual gear 508 on the basis of the first forward gear, that is, the first straight shift fork assembly 513 drives the first shifting dual gear The gear 507 slides until it does not mesh with the first gear 503 and the second gear 504, and at the same time, the second straight gear shift fork assembly 514 drives the second shifting dual gear 508 to slide until its large gear meshes with the third gear 505. The power input to the bevel gear 511 is transmitted to the second rotating shaft 502 through the straight bevel gear 509 , the first rotating shaft 501 , the large gear of the second shifting dual gear 508 and the third gear 505 in sequence. The forward fourth gear is to change the sliding position of the second shifting dual gear 508 on the basis of the forward third gear, that is, the second straight forward shifting fork assembly 514 drives the second shifting dual gear 508 to slide to its pinion and fourth gear. The gear 506 meshes, and now the power of the input bevel gear 511 is transmitted to the second rotating shaft 502 through the straight bevel gear 509, the first rotating shaft 501, the pinion of the second shifting dual gear 508 and the fourth gear 506 in sequence. The neutral gear is to change the sliding position of the first shifting dual gear 507 on the basis of the first gear forward, that is, the first straight shift fork assembly 513 drives the first shifting dual gear 507 to slide to the first gear 503 and the second gear. The blocking gears 504 are not meshed, and the power of the input bevel gear 511 is not transmitted to the second rotating shaft 502 after being transmitted to the first rotating shaft 501 . In the reverse gear position, the first straight-travel gear shift fork assembly 513 drives the first gear shift dual gear 507 to slide until it does not mesh with the first gear 503 and the second gear 504, and the second straight-travel gear shift fork assembly 514 Drive the second shifting dual gear 508 to slide until it does not mesh with the third gear 505 and the fourth gear 506, the reverse gear shift fork assembly 515 drives the reverse gear 512 to mesh with the second gear 504, and the power input to the bevel gear 511 is sequentially It is transmitted to the second rotating shaft 502 through the reverse bevel gear 510 , the reverse gear 512 and the second gear 504 .

In the biaxial multi-gear forward and reverse transmission device of this embodiment, the straight bevel gear 509 and the reverse bevel gear 510 adopt a coaxial design, and the power transmission of the forward gear and the reverse gear are carried out respectively, which greatly simplifies the reverse gear. The mechanism reduces the number of shafts and gears, improves the compactness of the structure and reduces the cost; moreover, two bevel gears, the straight bevel gear 509 and the reverse bevel gear 510, are used to mesh with the input bevel gear 511, which can better balance Due to the axial force generated by the meshing transmission of bevel gears, the axial serial movement of the first rotating shaft 501 is reduced; compared with the existing through-function transmission mechanism, the biaxial multi-gear forward and reverse transmission device has fewer shafts and gears, The utility model has the advantages of simple and compact structure, light weight, wide range of speed adaptation, low manufacturing cost, convenient installation, etc., and can be widely used in the transmission system of crawler tractors.

After the above-mentioned multi-gear forward and reverse conversion mechanism is combined with the high-low speed shift mechanism, it can further realize a total of 8 forward gears in 2×4, a high-speed reverse gear, a low-speed reverse gear and neutral gear, that is, the high-low speed shift mechanism is in the In the high-speed transmission state, the power through the high-low speed shift mechanism and the multi-gear forward and reverse conversion mechanism can realize four forward gears with different transmission ratios and one high-speed reverse gear. The high-low speed shifting mechanism and the multi-gear forward and reverse conversion mechanism can realize four forward gears with different transmission ratios and one low-speed reverse gear. After the combination of the multi-gear forward and reverse conversion mechanism and the high-low speed shift mechanism, the gear design is reasonable, the operation is convenient, and it can well adapt to the requirements of the operating speed of various working conditions of agricultural machinery.

In this embodiment, as shown in FIG. 2 and FIG. 3 , the first straight gear fork assembly 513, the second straight gear fork assembly 514, and the reverse gear fork assembly 515 all include a shift fork 521 and are slidably disposed on the box body. The shift shaft 522 on the 100, the shift fork 521 is fixedly connected on the shift shaft 522, the shift shaft 522 is connected with a sliding driver (not shown in the figure), and the sliding driver can adopt the existing technology, such as telescopic cylinder, Telescopic oil cylinder and the manual shifting mechanism of the existing transmission, etc. Preferably, the first straight-travel gear fork assembly 513, the second straight-travel gear fork assembly 514, and the reverse gear fork assembly 515 are each provided with an independent shift shaft 522, that is, the first straight-travel gear fork assembly 513 , the second straight travel gear fork assembly 514 and the reverse gear fork assembly 515 each include an independent shift fork 521 and a shift shaft 522 . In other embodiments, the first straight travel gear fork assembly 513 , the second straight travel gear shift fork assembly 514 and the reverse gear shift fork assembly 515 can also adopt other types of existing shift fork assemblies.

Further, the shift shaft 522 is slidably arranged in the slide seat fixedly connected to the box body 100, and a shift elastic positioning assembly is also provided between the shift shaft 522 and the slide seat, which is used for dialing in each gear state. The fork 521 is positioned; specifically, the gear shift elastic positioning assembly includes a pressing steel ball and a pressure spring, and a counterbore with an opening facing the shift shaft 522 is provided on the sliding seat, and the pressing spring and the pressing steel ball are sequentially installed in the counterbore The middle and compression spring makes the pressing steel ball close to the shift shaft 522, and the shift shaft 522 is provided with a plurality of positioning counterbores for pressing the pressing steel ball. When the shift fork 521 slides and controls the corresponding gears to be in each gear state, the pressing steel ball is just pressed into one of the positioning counterbores correspondingly, so as to realize the positioning of the shift fork 521 in this gear state and prevent the shift fork 521 from being arbitrarily move. Taking the first straight shift fork assembly 513 as an example, three positioning counterbores are provided on the shift shaft 522 corresponding to the first straight shift fork assembly 513. When the shift fork 521 is in the When the first gear 503 meshes, the pressing steel ball just presses into the first positioning counterbore, and when the shift fork 521 is in the position of making the first shifting double gear 507 mesh with the second gear 504, the pressing steel ball just presses into the first positioning counterbore. In the two positioning counterbores, when the shift fork 521 is in the first shift gear 507 and the first gear 503 and the second gear 504 are not meshed, the pressing steel ball is just pressed into the third positioning counterbore.

In this embodiment, the first shifting dual gear 507, the second shifting dual gear 508, and the reverse gear 512 are all provided with card slots, and the shift fork 521 corresponding to the first shifting dual gear 507 is provided with a ferrule U-shaped card in the card slot of the first shifting dual gear 507, the shift fork 521 corresponding to the second shifting dual gear 508 is provided with a U-shaped card sleeve in the card slot of the second shifting dual gear 508 Card, the shift fork 521 corresponding to the reverse gear 512 is provided with a U-shaped card sleeved in the slot of the reverse gear 512, and when the shift fork 521 slides along the shift shaft 522, the first shift double gear can be moved accordingly 507 , the second shift gear 508 and the reverse gear 512 slide along the first rotating shaft 501 . The structural form in which the shift fork 521 is connected and matched with the corresponding gear has the advantages of simple structure, easy manufacture and assembly, and stable and reliable operation.

In this embodiment, a power output gear 601 is fixedly installed on the second rotating shaft 502 for meshing with an external gear to output power. The power output gear 601 is mounted on the second rotating shaft 502 through spline fit, and the first speed gear 503, the second speed gear 504, the third speed gear 505, the fourth speed gear 506 and the power output gear 601 pass through the bushing and the power output gear 601 on the second rotating shaft 502. Bearings are positioned axially.

The above descriptions are only preferred implementations of the present utility model, and the protection scope of the present utility model is not limited to the above-mentioned embodiments. For those skilled in the art, the improvement and transformation obtained under the premise of not departing from the technical concept of the utility model should also be regarded as the protection scope of the utility model.

Claims (8)

1. A dual-shaft multi-gear forward and reverse transmission device, comprising a casing (100) and a first rotating shaft (501) and a second rotating shaft (502) installed side by side in the casing (100), the first A multi-gear forward and reverse conversion mechanism is provided between the rotating shaft (501) and the second rotating shaft (502). The gear (510), the input bevel gear (511) connected with the power source, and a plurality of power input gears installed on the second rotating shaft (502), the first rotating shaft (501) is equipped with a plurality of Any one of the power input gears is engaged or a gear shift assembly is not engaged with multiple power input gears. The straight travel bevel gear (509) is fixedly installed on the first rotating shaft (501), and the reverse gear bevel The gear (510) is rotatably set on the first rotating shaft (501), and the straight bevel gear (509) and the reverse bevel gear (510) are respectively arranged on both sides of the input bevel gear (511) and are connected with the input bevel gear. The gear (511) meshes, and the reverse gear (510) is slidably provided with a reverse gear (512) that can mesh with at least one of the multiple power input gears or not mesh with any of the multiple power input gears by sliding , the multi-gear forward and reverse conversion mechanism further includes a reverse gear fork assembly (515) for driving the reverse gear (512) to slide. 2. The biaxial multi-gear forward and reverse transmission device according to claim 1, characterized in that the plurality of power input gears are respectively the first gear (503), the second gear (504), the third gear (505) ) and the fourth gear (506), the first gear (503), the second gear (504), the third gear (505) and the fourth gear (506) are fixedly installed on the second rotating shaft (502), so The above-mentioned gear shifting assembly includes a first shifting dual gear (507) and a second shifting dual gear (508), and the first shifting dual gear (507) is slid on the first rotating shaft (501) and can choose one by sliding to mesh with the first gear (503) and the second gear (504) or not mesh with the first gear (503) and the second gear (504). (508) is slidably arranged on the first rotating shaft (501) and can choose one by sliding to mesh with the third gear (505) and the fourth gear (506) or with the third gear (505) and the fourth gear (506). not meshing, the gear shift assembly also includes a first straight shift fork assembly (513) for driving the first shift dual gear (507) to slide and a drive for driving the second shift dual gear ( 508) Sliding second straight travel gear fork assembly (514). 3. The dual-shaft multi-gear forward and reverse transmission device according to claim 2, characterized in that: the first straight-shift fork assembly (513), the second straight-shift fork assembly (514) and the reverse The shift fork assembly (515) includes a shift fork (521) and a shift shaft (522) slidingly arranged on the casing (100), and the shift fork (521) is fixed on the shift shaft (522). The shift shaft (522) is connected with a sliding drive member. 4. The dual-shaft multi-gear forward and reverse transmission device according to claim 3, characterized in that: the first straight-shift fork assembly (513), the second straight-shift fork assembly (514) and the reverse The shift fork assembly (515) is respectively provided with an independent shift shaft (522). 5. The dual-axis multi-gear forward and reverse transmission device according to claim 3, characterized in that: the shift shaft (522) is slid on a sliding seat fixed on the box body (100), so that A shift elastic positioning component is also arranged between the shift shaft (522) and the sliding seat. 6. The biaxial multi-gear forward and reverse transmission device according to claim 5, characterized in that: the shift elastic positioning assembly includes a pressing steel ball and a compression spring, and the sliding seat is provided with an opening facing the shift shaft (522), the compression spring and the compression steel ball are installed in the counterbore in sequence and the compression spring makes the compression steel ball close to the shift shaft (522), and the shift shaft (522) is provided with multiple A positioning counterbore for pressing in the pressing steel ball. 7. The biaxial multi-gear forward and reverse transmission device according to claim 3, characterized in that: the first shift dual gear (507), the second shift dual gear (508) and the reverse gear The bevel gears (510) are all provided with card slots, and the shift forks (521) corresponding to the first shifting dual gear (507), the second shifting dual gear (508) and the reverse bevel gear (510) are provided with There is a U-shaped card sleeved in the card slot. 8. The biaxial multi-gear forward and reverse transmission device according to any one of claims 1 to 7, characterized in that a power output gear (601) is fixedly installed on the second rotating shaft (502).