A transfer case with parking function for tractor

Abstract

The utility model relates to tractor transmission system technical field provides a kind of with the tractor with transfer case of parking function, including shell, shell top is installed and set up idler through idler axle, passive gear is meshed and set on idler, passive gear is set in shell by output shaft parallel with idler axle, several baffle plates are set on passive gear along the radial direction of output shaft, support pin shaft is set in shell bottom, friction plate group is slidably set on support pin shaft, several friction plates of friction plate group and several baffle plates are alternately spaced, and friction plate group is driven and compacted baffle plate by driving part to make passive gear stop movement. Transfer case has parking function, parking brake function and transfer case are integrated design, transfer case is independent box, can effectively improve the utilization space of tractor rear axle housing, so that overall structure is more compact.

Description

Technical Field

[0001] This utility model relates to the field of tractor transmission system technology, and in particular to a transfer case for a tractor with a parking function. Background Technology

[0002] In a tractor's transmission system, the transfer case is a key component for power distribution and transmission, while the parking brake mechanism is an important device for ensuring the tractor's parking safety. Currently, the parking brake mechanism of conventional tractors in the industry is usually integrated into the rear axle housing and specifically mounted on the small bevel gear shaft of the central drive.

[0003] This traditional structural layout has significant drawbacks: the parking brake mechanism occupies a large amount of space inside the rear axle housing, directly increasing the overall length of the rear axle housing. This problem not only restricts the overall layout of the tractor's transmission system, reducing the flexibility of its structural design, but also affects the arrangement of other functional components within the rear axle housing, failing to meet the modern tractor's demand for a compact and multifunctional transmission system.

[0004] Therefore, to address the above problems, a transfer case for tractors with a parking function is proposed to solve these problems. Utility Model Content

[0005] This invention addresses the shortcomings of existing technologies by developing a transfer case for tractors with a parking function. The transfer case integrates the parking brake function with the transfer case design. The transfer case is an independent housing, which can effectively improve the utilization space of the tractor's rear axle housing and make the overall structure more compact.

[0006] The technical solution to the technical problem solved by this utility model is as follows: This utility model provides a transfer case for a tractor with a parking function, including a housing, an idler wheel installed on the top of the housing via an idler wheel shaft, a driven gear meshing on the idler wheel, the driven gear being disposed inside the housing via an output shaft parallel to the idler wheel shaft, a plurality of partitions being disposed on the driven gear along the radial direction of the output shaft, a support pin being disposed at the bottom of the housing, a friction plate assembly being slidably disposed on the support pin, a plurality of friction plates and a plurality of partitions being alternately spaced, and the friction plate assembly being driven by a drive component to press the partitions to stop the driven gear from moving.

[0007] As an optimization, the drive component includes a parking cam mechanism and a pressure plate. The parking cam mechanism is rotatably mounted on the housing, and the pressure plate is mounted on the support pin. The parking cam mechanism rotates to abut against the pressure plate, and the pressure plate squeezes the friction plate to press the friction plate against the partition.

[0008] As an optimization, the parking cam mechanism includes a cam and a rotating rod. The rotating rod is rotatably mounted on the housing, and the bottom of the rotating rod is connected to the cam. The side of the cam near the pressure plate has an arc surface.

[0009] As an optimization, two support pins are provided, both of which are parallel to the output shaft and located on both sides below the output shaft. The number of friction plates in the friction plate group is one more than the number of partitions.

[0010] As an optimization, a steel ball is placed in the shaft hole of the output shaft by a spring. The steel ball is pressed by a meshing sleeve, which is fitted onto the output shaft. The meshing sleeve moves on the output shaft by a shift fork to achieve engagement and disengagement with the driven gear.

[0011] As an optimization, a limiting retaining ring is provided at the front end of the driven gear. The limiting retaining ring is sleeved on the output shaft and located at the contact point between the meshing sleeve and the driven gear.

[0012] As an optimization, the idler shaft is fixed to the housing by a set screw, the idler wheel is mounted on the idler shaft by a needle roller, and the driven gear is mounted on the output shaft by a needle roller bearing.

[0013] As an optimization, the front and rear ends of the output shaft are horizontally mounted on the housing via a first bearing and a second bearing, respectively.

[0014] As an optimization, an oil seal seat is provided at the front end of the housing, the front end of the output shaft passes through the oil seal seat and an oil seal is provided between the output shaft and the oil seal seat; a bearing cover is provided at the rear end of the housing.

[0015] As an optimization, a lower cover plate is provided at the bottom of the housing, and an oil drain plug is provided on the lower cover plate.

[0016] The effects provided in the utility model description are merely those of the embodiments, and not all the effects of the utility model. The above technical solution has the following advantages or beneficial effects: 1. The parking brake function is integrated with the transfer case. Since the transfer case is an independent housing structure, it is independent of the rear axle housing, which can effectively free up the internal space of the rear axle housing, allowing it to accommodate more gear structures or integrate other functional components, while ensuring the stability and reliability of the parking brake function, and significantly improving the overall performance and layout rationality of the tractor transmission system; 2. The parking cam mechanism drives the pressure plate to press the friction plate against the partition plate, and the friction force forces the passive gear to stop. Parking braking is achieved in the gear meshing state. This braking method has a short transmission path and rapid response. The alternating structure of the friction plate and the partition plate can increase the friction area, ensuring the stability and safety of parking braking. Attached Figure Description

[0017] The accompanying drawings are provided to further understand the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention and do not constitute a limitation thereof.

[0018] Figure 1 This is a cross-sectional view of the present invention; Figure 2 This is an overall structural diagram of the present invention; Figure 3 This is a schematic diagram of the output shaft power transmission of this utility model when disconnected; Figure 4 This is an enlarged view showing the positions of the friction pad assembly and partition in the parking state of this utility model; Figure 5 This is a structural diagram of the interior of the casing of this utility model.

[0019] In the diagram: 1. Housing; 2. Oil seal seat; 3. Output shaft; 4. Oil seal; 5. First bearing; 6. Lower cover plate; 7. Parking cam mechanism; 701. Cam; 702. Rotating rod; 7011. Arc surface; 8. Support pin; 9. Oil drain plug; 10. Pressure plate; 11. Partition plate; 12. Friction plate assembly; 13. Second bearing; 14. Bearing cover; 15. Needle roller bearing; 16. Driven gear; 17. Needle roller retaining ring; 18. Idler shaft; 19. Idler; 20. Needle roller; 21. Set screw; 22. Limiting retaining ring; 23. Shaft retaining ring; 24. Engaging sleeve; 25. Steel ball; 26. Spring. Detailed Implementation

[0020] To clearly illustrate the technical features of this solution, the present invention will be described in detail below through specific embodiments and in conjunction with the accompanying drawings. The following disclosure provides many different embodiments or examples for implementing different structures of the present invention. To simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Furthermore, the present invention may repeat reference numerals and / or letters in different examples. This repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. It should be noted that the components illustrated in the drawings are not necessarily drawn to scale. The present invention omits descriptions of well-known components and processing techniques and processes to avoid unnecessarily limiting the present invention. The terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate orientation or positional relationships based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0021] like Figures 1 to 5As shown, a transfer case for a tractor with a parking function includes a housing 1. An idler wheel 19 is mounted on the top of the housing 1 via an idler wheel shaft 18. A driven gear 16 is meshed on the idler wheel 19. The driven gear 16 is located inside the housing 1 via an output shaft 3 parallel to the idler wheel shaft 18. Several partitions 11 are arranged on the driven gear 16 along the radial direction of the output shaft 3. A support pin 8 is provided at the bottom of the housing 1. A friction plate assembly 12 is slidably arranged on the support pin 8. The friction plates can slide freely on the support pin 8, providing movement space for subsequent clamping braking. Several friction plates of the friction plate assembly 12 are alternately spaced with several partitions 11. The friction plate assembly 12 drives the clamping partitions 11 through a drive component to stop the driven gear 16 from moving. A shaft retaining ring 23 is provided on the driven gear 16 at the front end of the partition 11 to restrict the movement of the partition 11. By integrating the parking brake function into a separate housing in the transfer case, the space occupied by the tractor's rear axle housing is no longer required. This effectively shortens the length of the rear axle housing and provides ample space for increasing the number of gears or integrating other functional components within the rear axle housing, thereby enhancing the functional expandability of the transmission system.

[0022] In this embodiment, the driving component includes a parking cam mechanism 7 and a pressure plate 10. The parking cam mechanism 7 is rotatably mounted on the housing 1 and can rotate freely under external force. The pressure plate 10 is mounted on the support pin 8. The parking cam mechanism 7 rotates to abut against the pressure plate 10, and the pressure plate 10 presses the friction plate 12 to press against the partition plate 11. The parking cam mechanism 7 drives the pressure plate 10, causing the friction plate and the partition plate 11 to alternately press against each other. The friction force forces the driven gear 16 to stop, and parking braking is achieved in the gear meshing state. This braking method has a short transmission path, rapid response, and the alternating structure of the friction plate and the partition plate 11 can increase the friction area, ensuring the stability and safety of parking braking.

[0023] The parking cam mechanism 7 includes a cam 701 and a rotating rod 702. The rotating rod 702 is rotatably mounted on the housing 1, and the bottom of the rotating rod 702 is connected to the cam 701. The side of the cam 701 closest to the pressure plate 10 has an arc surface 7011. The parking cam mechanism 7 is connected to an externally mounted operating mechanism (not shown in the figure). The end of the rotating rod 702 away from the cam 701 extends through the left side wall of the housing 1. During operation, the operating mechanism drives the rotating rod 702 to rotate, and the cam 701 rotates accordingly, driving the pressure plate 10 to press the friction plate.

[0024] In this embodiment, two support pins 8 are provided, both of which are parallel to the output shaft 3 and are located on both sides below the output shaft 3. The pressure plate 10 is slidably mounted on the support pins 8. The height of the support pin 8 near the left side wall of the housing 1 is higher than that of the support pin 8 away from the left side wall of the housing 1. That is, the line connecting the two support pins 8 is inclined and the angle with the horizontal line is 10°-15°. The cam 701 is located between the two support pins 8. To avoid interference, the rotating rod 702 extends horizontally through the left side wall of the housing 1, and the distance between the rotating rod 702 and the support pin 8 near the left side wall of the housing 1 is greater than 5mm. The number of friction plates in the friction plate group 12 is one more than the number of partition plates 11, and the top of the friction plate is arc-shaped.

[0025] A steel ball 25 is placed in the shaft hole of the output shaft 3 by a spring 26. The steel ball 25 is pressed by a meshing sleeve 24. The meshing sleeve 24 is sleeved on the output shaft 3. The meshing sleeve 24 moves on the output shaft 3 by a fork to achieve engagement and disengagement with the driven gear 16.

[0026] In this embodiment, in order to avoid excessive compression or displacement when the meshing sleeve 24 abuts against the driven gear 16, a limiting ring 22 is provided at the front end of the driven gear 16. The limiting ring 22 is sleeved on the output shaft 3 and located at the abutment of the meshing sleeve 24 and the driven gear 16, which serves to limit and buffer.

[0027] The idler shaft 18 is fixed to the housing by a set screw 21. The idler 19 is mounted on the idler shaft 18 by a needle roller 20. The set screw 21 ensures the stability of the idler shaft 18 on the housing 1 and prevents loosening during transmission. The needle roller 20 reduces the coefficient of friction between the idler 19 and the idler shaft 18, improving the rotational flexibility of the idler 19. A needle roller retainer 17 is provided on the outside of the needle roller 20 to prevent it from dislodging. The driven gear 16 is mounted on the output shaft 3 by a needle roller bearing 15. The needle roller bearing 15 can withstand a large radial load while ensuring smooth rotation of the driven gear 16 on the output shaft 3.

[0028] In this embodiment, the front and rear ends of the output shaft 3 are horizontally mounted on the housing 1 via a first bearing 5 and a second bearing 13, respectively. The dual-bearing support structure ensures the coaxiality of the output shaft 3 during high-speed rotation, reducing vibration and misalignment.

[0029] An oil seal seat 2 is provided at the front end of the housing 1, and the front end of the output shaft 3 passes through the oil seal seat 2. An oil seal 4 is provided between the output shaft 3 and the oil seal seat 2. The oil seal 4 can effectively prevent the lubricating oil inside the housing 1 from leaking from the gap between the output shaft 3 and the oil seal seat 2, and at the same time prevent external dust and impurities from entering the housing 1. A bearing cover 14 is provided at the rear end of the housing 1. The bearing cover 14 can axially position the second bearing 13, prevent the second bearing 13 from axially moving during operation, and at the same time enhance the sealing of the rear end of the housing 1.

[0030] The bottom of the housing 1 is provided with a lower cover plate 6, and an oil drain plug 9 is provided on the lower cover plate 6. When it is necessary to change the lubricating oil inside the transfer case, simply unscrew the oil drain plug 9 to drain the waste oil, which is convenient to operate.

[0031] The internal structure of housing 1 is immersed in lubricating oil. Therefore, when the tractor needs to transmit power through the transfer case, the engagement sleeve 24 is moved axially along the output shaft 3 towards the driven gear 16 by the shift fork until the engagement sleeve 24 and the driven gear 16 are fully engaged. At this time, the power is transmitted sequentially to the idler wheel 19 through the external input mechanism. The idler wheel 19 drives the driven gear 16 to rotate through gear engagement. The rotation of the driven gear 16 drives the partition 11 to rotate, thereby causing the lubricating oil around the partition 11 to move. This keeps the friction plates and the partition 11 separated by the lubricating oil, preventing them from contacting each other. The driven gear 16 then transmits the power to the output shaft 3 through the engagement sleeve 24, and finally, the output shaft 3 outputs the power to the subsequent transmission components, realizing the transmission and distribution of power. When it is necessary to disconnect the power transmission, the engagement sleeve 24 is moved in the opposite direction by the shift fork, causing the engagement sleeve 24 to separate from the driven gear 16. The power transmission path is broken, and the output shaft 3 stops outputting power.

[0032] When the tractor stops and the parking brake is engaged, the parking cam mechanism 7 is rotated. Due to the characteristics of the cam profile of the parking cam mechanism 7, it generates an axial thrust on the pressure plate 10 during rotation, pushing the pressure plate 10 to move along the support pin 8 towards the friction plate assembly 12. During the movement, the pressure plate 10 squeezes the friction plate assembly 12, making the friction plates tightly fit against the partition 11. The friction between the friction plates and the partition 11 hinders the rotation of the partition 11, thereby stopping the rotation of the driven gear 16, which is fixedly connected to the partition 11. Since the driven gear 16 is still engaged with the idler gear 19 at this time, the stationary state of the driven gear 16 further restricts the rotation of the idler gear 19, ultimately achieving braking of the entire transmission system and ensuring that the tractor will not slip during parking, thus ensuring parking safety. When it is necessary to release the parking brake, the parking cam mechanism 7 is rotated in the opposite direction. The thrust of the cam on the pressure plate 10 disappears, the friction plate assembly 12 resets under its own elasticity, the friction plates separate from the partition 11, the driven gear 16 returns to its free rotation state, and the parking brake is released.

[0033] Although the specific embodiments of the utility model have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the utility model. Based on the technical solution of the utility model, various modifications or variations that can be made by those skilled in the art without creative effort are still within the scope of protection of the utility model.

Claims

1. A transfer case for a tractor with a parking function, comprising a housing (1), characterized in that: An idler wheel (19) is installed on the top of the housing (1) via an idler wheel shaft (18). A driven gear (16) is meshed on the idler wheel (19). The driven gear (16) is installed inside the housing (1) via an output shaft (3) parallel to the idler wheel shaft (18). Several partitions (11) are arranged on the driven gear (16) along the radial direction of the output shaft (3). A support pin (8) is provided at the bottom of the housing (1), and a friction plate group (12) is slidably arranged on the support pin (8). Several friction plates and several partitions (11) of the friction plate group (12) are alternately arranged, and the friction plate group (12) drives the partitions (11) to stop the movement of the driven gear (16) by driving the drive component.

2. The transfer case for a tractor with parking function according to claim 1, characterized in that: The driving components include a parking cam mechanism (7) and a pressure plate (10). The parking cam mechanism (7) is rotatably mounted on the housing (1), and the pressure plate (10) is mounted on the support pin (8). The parking cam mechanism (7) rotates to abut against the pressure plate (10), and the pressure plate (10) squeezes the friction plate assembly (12) so that the friction plate assembly (12) presses against the partition plate (11).

3. The transfer case for a tractor with parking function according to claim 2, characterized in that: The parking cam mechanism (7) includes a cam (701) and a rotating rod (702). The rotating rod (702) is rotatably mounted on the housing (1). The bottom of the rotating rod (702) is connected to the cam (701). The side of the cam (701) near the pressure plate (10) is provided with an arc surface (7011).

4. The transfer case for a tractor with a parking function according to claim 1 or 2, characterized in that: Two support pins (8) are provided. Both support pins (8) are parallel to the output shaft (3) and are located on both sides below the output shaft (3). The number of friction plates in the friction plate group (12) is one more than the number of partition plates (11).

5. The transfer case for a tractor with parking function according to claim 1 or 2, characterized in that: A steel ball (25) is placed in the shaft hole of the output shaft (3) by a spring (26). The steel ball (25) is pressed by a meshing sleeve (24). The meshing sleeve (24) is sleeved on the output shaft (3). The meshing sleeve (24) moves on the output shaft (3) by a fork to achieve engagement and disengagement with the driven gear (16).

6. The transfer case for a tractor with parking function according to claim 5, characterized in that: A limiting ring (22) is provided at the front end of the driven gear (16). The limiting ring (22) is sleeved on the output shaft (3) and located at the contact point between the meshing sleeve (24) and the driven gear (16).

7. The transfer case for a tractor with a parking function according to claim 1 or 2, characterized in that: The idler shaft (18) is fixed to the housing by a set screw (21), the idler wheel (19) is mounted on the idler shaft (18) by a needle roller (20), and the driven gear (16) is mounted on the output shaft (3) by a needle roller bearing (15).

8. The transfer case for a tractor with a parking function according to claim 1 or 2, characterized in that: The front and rear ends of the output shaft (3) are horizontally mounted on the housing (1) via the first bearing (5) and the second bearing (13), respectively.

9. The transfer case for a tractor with a parking function according to claim 8, characterized in that: An oil seal seat (2) is provided at the front end of the housing (1), and the front end of the output shaft (3) is provided through the oil seal seat (2), and an oil seal (4) is provided between the output shaft (3) and the oil seal seat (2); a bearing cover (14) is provided at the rear end of the housing (1).

10. The transfer case for a tractor with a parking function according to claim 1 or 2, characterized in that: The bottom of the housing (1) is provided with a lower cover plate (6), and an oil drain plug (9) is provided on the lower cover plate (6).

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