Reverse gear device and tractor
By designing a uniformly supported idler shaft and using a cylindrical roller bearing without an outer ring in the tractor's reverse gear, combined with retaining rings and oil passage lubrication, the problem of uneven load on the idler bearing was solved, the bearing life was extended, and the reliability and load-bearing capacity of the reverse gear were improved.
Patent Information
- Application Number
- CN202520636505.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-07
- Publication Date
- 2025-12-26
- Estimated Expiration
- 2035-04-07
AI Technical Summary
The idler bearing in the reverse gear of a tractor experiences a reduced lifespan due to uneven load. Furthermore, as horsepower increases, the working load and contact stress of the idler bearing increase, further shortening its service life.
Design a reverse gear device in which the vertical distance between the center of the two end support parts of the idler shaft and the midpoint of the idler is equal. It adopts a full complement cylindrical roller bearing without an outer ring, and the idler is positioned by the retaining ring and the housing. Axial oil passages and oil grooves are provided to uniformly lubricate the bearing.
This design achieves uniform force distribution on the idler gear bearing, avoids uneven loading, extends the bearing's service life, and improves the reliability and load-bearing capacity of the reverse gear device, making it suitable for high-horsepower tractors.
Smart Images
Figure CN223725376U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the field of agricultural machinery transmission, in particular, relates to a reverse gear device and a tractor. BACKGROUND
[0002] The reverse gear device in the transmission system of the tractor is generally arranged in the auxiliary gearbox or behind the gearbox, so that each forward gear has a reverse gear of a corresponding speed. However, as the horsepower increases, the working load of the idler 200 and the idler bearing 300a of the reverse gear device and the contact stress of the idler bearing 300a also increase, and the number of stress changes that the idler bearing 300a can withstand before pitting damage occurs also decreases accordingly, that is, the service life of the bearing is reduced.
[0003] As shown in Figure 1 The left support span L1 and the right support span L2 of the idler shaft 100 and the difference between the two are large, so that the idler bearing 300a is unbalanced, that is, the working load of the left bearing is much larger than that of the right bearing, and the overall service life is rapidly reduced. After the left bearing is damaged, the reliability of the reverse gear device of the tractor is greatly reduced. CONTENT OF THE INVENTION
[0004] The purpose of the present application is to provide a reverse gear device and a tractor to improve the service life of the bearing.
[0005] To achieve the above-mentioned purpose, the present application provides a reverse gear device in one aspect, which comprises:
[0006] An idler shaft sleeved with an idler;
[0007] A bearing set arranged between the idler shaft and the idler;
[0008] A housing, both axial ends of the idler shaft are inserted into the housing, and the outer periphery of the idler shaft on the side facing the housing is formed with a first support portion and a second support portion, and the first support portion and the second support portion are arranged close to the axial ends, respectively;
[0009] The vertical distance between the center of the first support portion and the midpoint of the idler is equal to the vertical distance between the center of the second support portion and the midpoint of the idler.
[0010] In some embodiments, the bearing set comprises two bearings arranged in sequence along the axial direction, and the vertical distance between the center of each bearing and the center of the adjacent support portion is equal.
[0011] In some embodiments, the bearings of the bearing set are full-cylinder-roller bearings without outer rings.
[0012] In some embodiments, the reverse gear device further comprises:
[0013] The first and second blocking rings are sleeved on the idler shaft and are located at the axial ends of the idler respectively to limit the idler in the axial direction.
[0014] In some embodiments, the sides of the first and second blocking rings away from the idler abut against the housing, and the ends of the first and second blocking rings close to the idler shaft extend towards the bearing set with a limiting part abutting against the bearing set.
[0015] In some embodiments, the first and second blocking rings are arranged at both axial ends of the bearing set and form oil grooves.
[0016] In some embodiments, one end of the idler shaft is formed with a stepped part, and the end of the first blocking ring towards the one end of the idler shaft abuts against the vertical surface of the stepped part.
[0017] In some embodiments, the idler is provided with an oil channel in communication with the bearing set, and the oil channel penetrates the idler in the radial direction.
[0018] In some embodiments, the outer periphery of the idler has a plurality of gear teeth, and the oil channel is formed between two adjacent gear teeth.
[0019] Another aspect of the present application protects a tractor, which comprises the reverse gear device described above.
[0020] Through the above technical solution, the reverse gear device provided by the embodiments of the present application has the following beneficial effects:
[0021] In the technical solution of the present application, the idler shaft is jointly carried by the first and second support parts and the bearing, and after the idler shaft is loaded, since the vertical distance between the center of the first support part and the midpoint of the idler is equal to the vertical distance between the center of the second support part and the midpoint of the idler, the bearing set will not be additionally stressed by the deflection torque generated due to the uneven stress between the first and second support parts, that is, the bearing set is uniformly stressed, which can avoid the eccentric loading of the bearing set and further prolong the service life of the bearing set.
[0022] Other features and advantages of the embodiments of the present application will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF DRAWINGS
[0023] The accompanying drawings are included to provide a further understanding of the embodiments of the present application, and constitute a part of the specification, and are used together with the following specific embodiments to explain the embodiments of the present application, but do not constitute a limitation on the embodiments of the present application. For those skilled in the art, other drawings can be obtained from the structures shown in the drawings without creative labor. In the drawings:
[0024] Figure 1 is a structural schematic diagram of a reverse gear device of the prior art;
[0025] Figure 2 Structure diagram of the reverse gear device according to the specific embodiment of the present application.
[0026] Explanation of reference signs
[0027] C midpoint L1 left support span
[0028] L2 right support span D1 first support span
[0029] D2 second support span R limiting portion
[0030] 100 idler shaft 110 first support portion
[0031] 120 second support portion 130 stepped portion
[0032] 200 idler gear 300 bearing set
[0033] 400 housing 500 first retainer ring
[0034] 600 second retainer ring 700 oil groove
[0035] 800 oil passage 300a idler gear bearing
[0036] k elastic retainer ring p spacer Specific embodiment
[0037] The specific embodiment of the present application is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiment described herein is only used to illustrate and explain the present application, and is not used to limit the present application.
[0038] The reverse gear device and tractor according to the present application are described below with reference to the accompanying drawings.
[0039] The present application discloses a new type of reverse gear device, as shown in a specific embodiment, the reverse gear device comprises: Figure 2
[0040] idler shaft 100, which is sleeved with idler gear 200;
[0041] bearing set 300, which is arranged between idler shaft 100 and idler gear 200;
[0042] housing 400, both axial ends of idler shaft 100 are inserted into housing 400, and the outer periphery of idler shaft 100 on the side facing housing 400 is formed with first support portion 110 and second support portion 120, and first support portion 110 and second support portion 120 are arranged close to the axial ends respectively;
[0043] The vertical distance between the center of the first support part 110 and the midpoint C of the idler wheel 200 is equal to the vertical distance between the center of the second support part 120 and the midpoint C of the idler wheel 200.
[0044] Specifically, referring to Figure 2 In order to ensure the pivoting movement of the idler wheel 200 relative to the idler shaft 100, a bearing set 300 is arranged between the idler shaft 100 and the idler wheel 200. The idler shaft 100 is fixed by a housing 400, and the contact parts of the idler shaft 100 and the housing 400 are formed into the first support part 110 and the second support part 120, respectively. In the prior art, the left support span L1 and the right support span L2 of the idler shaft 100 are large, which easily causes the idler bearing 300a to be unbalanced. The vertical distance between the center of the first support part 110 and the midpoint C of the idler wheel 200 is equal to the vertical distance between the center of the second support part 120 and the midpoint C of the idler wheel 200, so that the forces between the first support part 110 and the second support part 120 are uniform, and no additional deflection torque is generated, so that the bearing set 300 is not additionally stressed due to the additional deflection torque, thereby avoiding the unbalanced loading of the bearing set 300. In addition, the first support part 110 and the second support part 120 are arranged close to the two axial ends, respectively, so as to reduce the length of the force arm of the first support part 110 and the second support part 120 relative to the idler shaft 100, improve the support stiffness of the idler shaft 100, and thus reduce the deformation of the idler shaft 100 under load. In this way, not only the unbalanced loading of the idler wheel 200 can be avoided, but also the reliability of the idler shaft 100 can be improved.
[0045] In the present embodiment, as shown in Figure 2 The bearing set 300 includes two bearings arranged in sequence along the axial direction, and the vertical distance between the center of each bearing and the center of the adjacent support part is equal. In this way, the length of the first support span D1 is equal to the length of the second support span D2, that is, the length of the force arm of the support force of each bearing relative to the idler shaft 100 is equal, the load of each bearing is uniform, the working life is similar, and the premature damage of a single bearing can be avoided, thereby improving the reliability of the reverse gear device.
[0046] In the present embodiment, as shown in Figure 2 The bearing of the bearing set 300 is a full-cylinder-roller bearing without an outer ring.
[0047] Compared with the prior art, the bearing selected is a common cylindrical bearing, the full-load cylindrical roller bearing without an outer ring of the application not only has a high basic dynamic load, but also can improve the working load of the reverse gear device, and the inner hole of the idler gear 200 can directly serve as the outer ring of the bearing, so that the inner hole of the idler gear 200 can be maximized, that is, after the size of the root circle of the idler gear 200 is fixed, a sufficient distance between the inner hole and the root circle (the radial distance from the inner hole to the root circle needs to be greater than 3.5 times the modulus) needs to be ensured to ensure the structural strength of the idler gear 200 after being loaded. If the inner hole is too small, the carrying capacity and service life of the reverse gear device will also be reduced due to the size limitation of the bearing that can be assembled in the inner hole.
[0048] In the embodiment, as shown in Figure 2 The reverse gear device further comprises:
[0049] The first retainer 500 and the second retainer 600 are sleeved on the idler shaft 100, and the first retainer 500 and the second retainer 600 are located at the axial two ends of the idler gear 200 to limit the idler gear 200 in the axial direction. In this way, the first retainer 500 and the second retainer 600 can jointly clamp the idler gear 200 to achieve positioning of the idler gear 200, and the structure is simple and convenient to disassemble and assemble.
[0050] In the embodiment, as shown in Figure 2 The side of the first retainer 500 and the second retainer 600 away from the idler gear 200 abuts against the housing 400, and the end of the first retainer 500 and the second retainer 600 close to the idler shaft 100 extends a limiting portion R toward the bearing set 300, and the limiting portion R abuts against the bearing set 300. Specifically, the two sides of the inner wall of the housing 400 abut against the outer sides of the first retainer 500 and the second retainer 600 respectively, and the inner sides of the first retainer 500 and the second retainer 600 abut against the two sides of the inner ring of the bearing set 300 respectively. In this way, the first retainer 500, the second retainer 600 and the housing 400 can jointly achieve positioning of the bearing set 300 and the idler gear 200 without introducing additional components, and the overall structure is compact.
[0051] In the embodiment, as shown in Figure 2 The first retainer 500 and the second retainer 600 are spaced apart from the axial two ends of the bearing set 300 and form an oil groove 700. The oil groove 700 can accommodate lubricating grease to lubricate the bearing set 300, thereby prolonging the service life of the bearing set 300.
[0052] In the embodiment, as shown in Figure 2As shown, one end of the idler shaft 100 is formed with a stepped portion 130, and the first retainer ring 500 is limited to abut against the vertical surface of the stepped portion 130 at one end of the idler shaft 100. After the design of the stepped portion 130 is added, the idler shaft 100 can be positioned in one direction through the abutting effect of the first retainer ring 500 and the stepped portion 130. The overall structure is simple, and the positioning is convenient, which is beneficial to the disassembly and assembly of the idler shaft 100.
[0053] If the bearing set 300 is only lubricated by the oil groove 700, the inside of the bearing can not be sufficiently lubricated, which causes the temperature change speed of the inside of the bearing to be greater than that of the outer end of the bearing, affecting the service life of the bearing. In the embodiment, as shown, Figure 2 As shown, the idler 200 is provided with an oil channel 800 in communication with the bearing set 300, and the oil channel 800 penetrates the idler 200 in the radial direction. In this way, it is beneficial to ensure that the inside of the bearing set 300 is also sufficiently lubricated, so that the temperature rise of the inside of the bearing is uniform, thereby avoiding excessive deformation of the inside due to temperature difference and causing uneven load.
[0054] In order to ensure the lubrication effect of the inside of the bearing. In the embodiment, as shown, Figure 2 As shown, the outer periphery of the idler 200 has a plurality of teeth, and the oil channel 800 is formed between two adjacent teeth. In this way, during the meshing of the idler 200, the tips of the teeth can squeeze the lubricating oil into the oil channel 800, thereby improving the lubrication effect of the oil channel 800 on the bearing set 300. The number of oil channels 800 is not limited to Figure 2 As shown, the number of oil channels 800 is not limited to one, and each oil channel 800 can be arranged in the axial and circumferential directions of the idler 200 in sequence to improve the lubrication effect.
[0055] The present application discloses a new type of tractor, and the tractor in a specific embodiment includes the reverse gear device described above. Obviously, the tractor also has all the technical effects of the reverse gear device described above, which will not be repeated here.
[0056] As described above, the first support part 110 and the second support part 120 in the reverse gear device of the present application are uniformly stressed, avoiding the generation of deflection torque and preventing the bearing set 300 from being unevenly loaded. The two are arranged close to the two ends in the axial direction, shortening the length of the force arm, enhancing the support stiffness of the idler shaft 100, reducing deformation, thereby improving the reliability of the idler shaft 100 and avoiding uneven loading of the idler 200.
[0057] On the basis of the above, the present application adopts a full-cylinder-roller bearing without an outer ring, which maximizes the inner hole of the idler 200 to ensure the load capacity of the bearing and the idler 200.
[0058] The first check ring 500, the second check ring 600 and the housing 400 jointly realize the positioning of the bearing set 300 and the idler gear 200. After the idler gear 200 is loaded, the bearing set 300 can be lubricated not only by the oil groove 700 formed by the first check ring 500 and the second check ring 600 being arranged at the axial two ends of the bearing set 300, but also by the oil channel 800 formed between two adjacent teeth, so that the lubrication effect is good and the temperature rise is uniform.
[0059] Preferably, the engine output power of the tractor adopting the reverse gear device can be not less than 200 horsepower, in other words, as the horsepower increases, the working load of the idler gear 200 and the idler gear bearing of the reverse gear device and the contact stress of the idler gear bearing also increase, and the number of stress changes that the idler gear bearing can withstand before pitting damage occurs also decreases accordingly. Due to the above technical effects, the reverse gear device of the present application can be preferably applied to high-horsepower tractors to improve the working life of the idler gear bearing.
[0060] In the description of the present application, it should be understood that the terms "first", "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can be explicitly or implicitly included at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically limited.
[0061] In the present application, unless otherwise specifically defined and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected or communicate with each other; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise specifically limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.
[0062] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the present description, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples described in the present description and the features of different embodiments or examples without contradiction.
Claims
1. A reverse gear device characterized by comprising: The reverse gear device comprises: a idler shaft (100) sleeved with an idler (200); a bearing set (300) arranged between the idler shaft (100) and the idler (200); a housing (400) into which the axial ends of the idler shaft (100) are inserted, and the outer periphery of the idler shaft (100) is formed with a first support portion (110) and a second support portion (120) on the side of the housing (400), and the first support portion (110) and the second support portion (120) are arranged close to the axial ends, respectively; wherein the vertical distance between the center of the first support portion (110) and the midpoint (C) of the idler (200) is equal to the vertical distance between the center of the second support portion (120) and the midpoint (C) of the idler (200).
2. The reverse device of claim 1, wherein, The bearing set (300) comprises two bearings arranged in sequence along the axial direction, and the vertical distance between the center of each bearing and the center of the adjacent support portion is equal.
3. The reverse device of claim 1, wherein, The bearings of the bearing set (300) are full-cylinder-roller bearings without outer rings.
4. The reversing device according to any one of claims 1 to 3, characterized in that The reverse gear device further comprises: a first retainer ring (500) and a second retainer ring (600) both sleeved on the idler shaft (100), and the first retainer ring (500) and the second retainer ring (600) are located at the axial ends of the idler (200) to limit the idler (200) in the axial direction.
5. The reverse device of claim 4, wherein, The side of the first retainer ring (500) and the second retainer ring (600) away from the idler (200) abuts against the housing (400), and the end of the first retainer ring (500) and the second retainer ring (600) close to the idler shaft (100) extends a limiting portion (R) toward the bearing set (300), and the limiting portion (R) abuts against the bearing set (300).
6. The reverse device of claim 4, wherein, The first retainer ring (500) and the second retainer ring (600) are arranged away from the axial ends of the bearing set (300) and form an oil groove (700).
7. The reverse device of claim 4, wherein, One end of the idler shaft (100) is formed with a stepped portion (130), and the end of the first retainer ring (500) toward the idler shaft (100) abuts against the vertical surface of the stepped portion (130).
8. The reverse device of claim 1, wherein, The idler (200) is provided with an oil channel (800) in communication with the bearing set (300), and the oil channel (800) penetrates the idler (200) in the radial direction.
9. The reverse device of claim 8, wherein, The outer periphery of the idler (200) has a plurality of gear teeth, and the oil channel (800) is formed between two adjacent gear teeth.
10. A tractor characterised in that, The tractor comprises the reverse gear device according to any one of claims 1-9.