Large idle gear structure suitable for high-horsepower engine
By employing rolling bearings and oil passage design in the idler gear structure of high-horsepower engines, the problems of frictional heating and adhesion caused by poor lubrication of the idler gears are solved, thereby achieving the reliability of the lubrication system and the stable operation of the engine.
Patent Information
- Application Number
- CN202520076016.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-14
- Publication Date
- 2025-10-28
- Estimated Expiration
- 2035-01-14
AI Technical Summary
In high-horsepower engines, idler gears are prone to friction and heat generation due to poor lubrication during high-speed operation, which can lead to bushing sticking to the shaft, causing bushing burnout or failure to rotate properly. Furthermore, the lubricating oil cannot be replenished in time, creating a vicious cycle.
The rolling bearing solution is adopted. The rolling bearing is interference-fitted with the idler gear shaft. The friction force is transferred by rolling, which reduces frictional heat generation. The oil passage and oil cavity system ensures timely supply of lubricating oil, avoids dry friction surface and achieves effective lubrication.
It effectively solves the problem of idler gear bushing burning or rotational failure, improves the reliability of the lubrication system, avoids the temperature rise of the friction surface and the expansion of components, and ensures the normal operation of the engine.
Smart Images
Figure CN223483346U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of engine component technology, specifically to a large idler gear structure suitable for high-horsepower engines. Background Technology
[0002] Among various mechanical products, the exploration of engine gear transmission technology is the most common. Existing technologies struggle to solve the problems of bushing burnout or misalignment in engine idler gears, especially in high-horsepower engines. These engines experience high thermal loads and high speeds, making the idler gears more prone to bushing burnout or misalignment failures. A new idler gear structure for high-horsepower engines requires minimal modification to the original engine, significantly improving fuel economy and emissions while maintaining the original engine's power performance.
[0003] The direct cause of bushing combustion or follow-through failure between the idler gear and idler gear shaft is abnormal heating between the gear bushing and gear shaft. The cause of abnormal heating is the continuous high-speed relative rotational friction between the gear hole and the outer surface of the shaft under poor lubrication. After the friction begins, abnormal lubrication system, blocked oil passage, and untimely oil pump supply cause the friction surface to be in a dry state and heat up rapidly. This heating immediately causes the physical expansion of related components, directly leading to the disappearance of normal fit clearance, blocking the oil passage, and subsequent lubricating oil cannot enter the friction surface. The temperature of the friction surface rises rapidly, and the mating surface of the shaft and bushing reaches a molten state, resulting in adhesion. That is: high-speed gear rotation → lubrication system failure → friction pair heating → gear and shaft expansion → disappearance of fit clearance → closure of the circulation channel on the shaft surface → crankshaft gear driving large idler gear to rotate normally at high speed → friction pair heating up rapidly → bushing and shaft adhesion.
[0004] The above describes a vicious cycle between lubrication performance and heat generation. During this process, the large idler gear is constantly rotating at high speed and is not subject to load limitations from other gears in the gear system and the PTO until the machine fails and stops. Therefore, it is urgent to solve the problems mentioned above. Utility Model Content
[0005] The purpose of this invention is to provide a large idler gear structure suitable for high-horsepower engines to solve the problem of abnormal heat generation between the gear bushing and the gear shaft, which causes the physical expansion of related components, directly leading to the disappearance of normal fit clearance, blockage of oil passages, and subsequent inability of lubricating oil to enter the friction surface, resulting in a rapid increase in the temperature of the friction surface and the mating surface of the shaft and bushing reaching a molten state.
[0006] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows:
[0007] A large idler gear structure suitable for high-horsepower engines includes a large idler gear assembly and an idler gear shaft. The large idler gear assembly has a through hole in the middle for the idler gear shaft to pass through. An annular protrusion is provided in the middle of the through hole. A through hole is provided in the middle of the annular protrusion. The idler gear shaft passes through the through hole. Sealing devices are provided on the left and right sides of the annular protrusion. An oil cavity is formed between the sealing devices, the idler gear shaft, and the through hole. The central axis of the idler gear shaft and the central axis of the large idler gear assembly are on the same horizontal line. The idler gear shaft is fixed to the engine gear chamber by bolts to ensure bearing clearance under the compressed state. An oil passage is provided on the idler gear shaft, and the oil passage is connected to the oil cavity.
[0008] Further specified, the annular protrusion and the large idler gear assembly are integrally cast, the cross-section of the annular protrusion and the through hole in the middle of the large idler gear assembly are inverted convex, the large idler gear assembly includes a large idler gear and a small idler gear, the large idler gear and the small idler gear are integrally cast, and the central axis of the large idler gear and the central axis of the small idler gear are on the same horizontal line.
[0009] Further specified, the idler gear shaft is fitted with a bushing with clearance fit, the sealing device is a tapered roller bearing, the tapered roller bearing includes a left tapered roller bearing and a right tapered roller bearing, respectively located on the left and right sides of the annular protrusion, the distance from the left end face of the annular protrusion to the left end face of the small idler gear is L1, the distance from the right end face of the annular protrusion to the right end face of the large idler gear is L2, the left tapered roller bearing and the right tapered roller bearing are respectively limited by dimensions L1 and L2, the outer diameter of the left tapered roller bearing and the right tapered roller bearing match the inner diameter of the through hole, the bushing is located between the left tapered roller bearing and the right tapered roller bearing, the width of the bushing matches the width of the annular protrusion, and an oil cavity is formed between the bushing, the left tapered roller bearing, the right tapered roller bearing and the annular protrusion.
[0010] Further defining the oil passage, the oil passage includes a transverse oil passage and a vertical oil passage. The transverse oil passage is located at the transverse center position of the idler gear shaft, and the vertical oil passage passes through the side wall of the idler gear shaft and is connected to the transverse oil passage.
[0011] Furthermore, the bushing is provided with an oil hole.
[0012] The advantages of this utility model over the current technology are as follows:
[0013] This invention employs a rolling bearing solution, in which the rolling bearing is interference-fitted with the idler gear shaft. The rolling bearing provides support and utilizes the rolling motion of the rollers to transfer the friction between the idler gear shaft and the bushing, reducing heat generation from the contact of the friction pair and thus solving the problem of the large idler gear burning the bushing or rotating in the same direction. Attached Figure Description
[0014] Figure 1 This is a three-dimensional assembly diagram of the large idler gear structure in this utility model.
[0015] Figure 2 This is a schematic diagram of the main structure of the large idler gear assembly of this utility model.
[0016] Figure 3 for Figure 2 BB-direction cross-section schematic diagram
[0017] Figure 4 This is a schematic cross-sectional view of the assembly of the large idler gear assembly and the idler gear shaft in this utility model.
[0018] The markings in the diagram correspond to: 1-Idler shaft, 2-Large idler gear, 3-Small idler gear, 4-Annular protrusion, 5-Conical roller bearing, 6-Bushing, 7-Oil cavity, 8-Bolt, 9-Transverse oil passage, 10-Vertical oil passage, 11-Oil hole. Detailed Implementation
[0019] To enable those skilled in the art to better understand the technical solution of this utility model, the technical solution of this utility model will be further described below in conjunction with the accompanying drawings and embodiments. Example
[0020] like Figure 1-Figure 4As shown, a large idler gear structure suitable for high-horsepower engines includes a large idler gear assembly and an idler gear shaft. The large idler gear assembly has a through hole in the middle for the idler gear shaft 1 to pass through. A ring-shaped protrusion 4 is provided in the middle of the through hole. The large idler gear assembly includes a large idler gear 2 and a small idler gear 3, which are integrally cast. The central axis of the large idler gear 2 and the central axis of the small idler gear 3 are on the same horizontal line. The ring-shaped protrusion 4 and the large idler gear assembly are integrally cast. The cross-section of the through hole in the middle of the large idler gear assembly is convex. Sealing devices are provided on both the left and right sides of the annular protrusion 4. These sealing devices are tapered roller bearings 5, including a left tapered roller bearing and a right tapered roller bearing, located on the left and right sides of the annular protrusion 4 respectively. The distance from the left end face of the annular protrusion 4 to the left end face of the small idler gear 3 is L1, and the distance from the right end face of the annular protrusion 4 to the right end face of the large idler gear 2 is L2. The left and right tapered roller bearings are respectively... Limiting is achieved by dimensions L1 and L2. The outer diameters of the left and right tapered roller bearings match the inner diameter of the through-hole, forming an interference fit. The tapered roller bearing 5 conforms to the GB / T297-32011 standard. A bushing 6 is provided between the left and right tapered roller bearings, and the width of the bushing 6 matches the width of the annular protrusion 4. An oil cavity 7 is formed between the bushing 6, the left and right tapered roller bearings, and the annular protrusion 4. An idler gear... The central axis of shaft 1 and the central axis of the large idler gear assembly are on the same horizontal line. The idler gear shaft 1 is fixed to the engine gear chamber by bolts 8 to ensure bearing clearance under the clamped state. Oil passages are provided on the idler gear shaft 1, including a transverse oil passage 9 and a vertical oil passage 10. The transverse oil passage 9 is located at the transverse center of the idler gear shaft 1, and the vertical oil passage 10 passes through the side wall of the idler gear shaft 1 and is connected to the transverse oil passage 9. An oil hole 11 is provided on the bushing 6, and the oil passage is connected to the oil cavity 7 through the oil hole 11.
[0021] The formula for calculating axial force is: F=T / kd, where F is the axial force, T is the tightening torque (50 Nm), K is the torque coefficient (0.2), and d is the major diameter of the thread (10 mm). The calculated axial force of each bolt is 25 kN, and since four bolts are used, the total axial force is 100 kN. Therefore, under the condition of 100 kN axial force bolt fixing, the bearing clearance of the tapered roller bearing 5 must be controlled within the range of 0.05~0.1 mm. Oil enters through the transverse oil passage 9 and vertical oil passage 10 on the idler gear shaft 1, and enters the oil chamber 7 through the oil hole 11 on the bushing 6. The oil chamber 7 provides lubrication to the tapered roller bearing 5 and to the bushing 6 and idler gear shaft 1.
[0022] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0023] The above provides a detailed description of a large idler gear structure suitable for high-horsepower engines provided by this utility model. The description of the specific embodiments is only for the purpose of helping to understand the method and core idea of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made to this utility model without departing from the premise of this utility model, and these improvements and modifications also fall within the protection scope of the claims of this utility model.
Claims
1. A large idler gear structure suitable for high-horsepower engines, characterized in that: The system includes a large idler gear assembly and an idler gear shaft (1). The large idler gear assembly has a through hole in the middle for the idler gear shaft (1) to pass through. The through hole has an annular protrusion (4) in the middle. The annular protrusion (4) has a through hole in the middle. The idler gear shaft (1) passes through the through hole. Sealing devices are provided on the left and right sides of the annular protrusion (4). An oil cavity (7) is formed between the sealing device, the idler gear shaft (1) and the through hole. The central axis of the idler gear shaft (1) and the central axis of the large idler gear assembly are on the same horizontal line. The idler gear shaft (1) is fixed to the engine gear chamber by bolts (8) to ensure bearing clearance under the compressed state. An oil passage is provided on the idler gear shaft (1). The oil passage is connected to the oil cavity (7).
2. The large idler gear structure suitable for high-horsepower engines according to claim 1, characterized in that: The annular protrusion (4) and the large idler gear assembly are integrally cast. The cross-section of the annular protrusion (4) and the through hole in the middle of the large idler gear assembly is inverted convex. The large idler gear assembly includes a large idler gear (2) and a small idler gear (3). The large idler gear (2) and the small idler gear (3) are integrally cast. The central axis of the large idler gear (2) and the central axis of the small idler gear (3) are on the same horizontal line.
3. The large idler gear structure suitable for high-horsepower engines according to claim 2, characterized in that: The idler gear shaft (1) is fitted with a bushing (6) with clearance fit. The sealing device is a tapered roller bearing (5). The tapered roller bearing (5) includes a left tapered roller bearing and a right tapered roller bearing, which are located on the left and right sides of the annular protrusion (4), respectively. The distance from the left end face of the annular protrusion (4) to the left end face of the small idler gear (3) is L1, and the distance from the right end face of the annular protrusion (4) to the right end face of the large idler gear (2) is L2. The left tapered roller bearing... The bearing and the right tapered roller bearing are respectively limited by dimensions L1 and L2. The outer diameter of the left tapered roller bearing and the right tapered roller bearing are matched with the inner diameter of the through hole. The bushing (6) is located between the left tapered roller bearing and the right tapered roller bearing. The width of the bushing (6) is matched with the width of the annular protrusion (4). An oil cavity (7) is formed between the bushing (6), the left tapered roller bearing, the right tapered roller bearing and the annular protrusion (4).
4. The large idler gear structure suitable for high-horsepower engines according to claim 3, characterized in that: The oil passage includes a transverse oil passage (9) and a vertical oil passage (10). The transverse oil passage (9) is located at the transverse center of the idler gear shaft (1), and the vertical oil passage passes through the side wall of the idler gear shaft (1) and is connected to the transverse oil passage (9).
5. A large idler gear structure suitable for high-horsepower engines according to claim 3, characterized in that: The bushing (6) is provided with an oil hole (11).