Input gear shaft facilitating lubricating grease filling

Abstract

The utility model discloses a kind of input gear shafts facilitating lubricating grease filling, it includes input gear shaft, its axial center is equipped with through filling cavity, the front end of filling cavity is connected to input shaft outer spline and motor inner spline connecting cavity, rear end is closed by detachable oil filler plug.This application adopts hierarchical dismounting design, only needs to dismount main reduction end cover and oil filler plug during maintenance, without dismounting driving motor, it can expose through filling cavity and carry out lubricating operation.The design makes single-person operation time reduce by more than 60%, greatly shortens maintenance cycle, improves equipment attendance rate and use efficiency.

Description

Technical Field

[0001] This utility model relates to the field of electric drive axle main reducer structure, and in particular to an input gear shaft structure that facilitates grease filling. Background Technology

[0002] As a core component of the power transmission in new energy vehicles and commercial vehicles, the main reducer of the electric drive axle connects its input gear shaft to the internal spline of the drive motor via an external spline, and operates under high-speed, heavy-load conditions for extended periods. To ensure reliable lubrication of the spline pair, reduce wear, and extend service life, it is necessary to periodically apply high-temperature grease.

[0003] Currently, traditional input gear shaft structures do not have a dedicated grease filling channel. Maintenance requires the entire drive motor to be disassembled to expose the splined connection for lubrication. This method has the following significant drawbacks: 1. The disassembly and assembly process is cumbersome and time-consuming, severely impacting vehicle uptime and operational efficiency; 2. Frequent disassembly and assembly can easily damage the motor wiring harness, connectors, and sealing elements, introducing new failure risks; 3. High maintenance costs and high professional requirements make it difficult for users to quickly implement maintenance; 4. Traditional integrated sealing designs are not only difficult to disassemble, but may also reduce sealing reliability during repeated assembly.

[0004] Therefore, it is necessary to propose a new solution to address the structural defects of existing input gear shafts in terms of lubrication maintenance, so as to achieve fast, simple and reliable grease filling and overcome the shortcomings of existing technologies. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and provide an input gear shaft that is easy to lubricate with grease.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows: An input gear shaft that facilitates grease filling includes an input gear shaft with a through filling cavity at its axial center. The front end of the filling cavity leads to the cavity connecting the external spline of the input shaft and the internal spline of the motor, and the rear end is sealed by a removable grease plug.

[0007] Furthermore, the coaxiality error between the filling cavity and the input gear shaft is no greater than 0.01 mm.

[0008] Furthermore, the diameter of the filling cavity is not less than Φ8mm, and the thickness of the shaft portion of the input gear shaft on one side is not less than 8mm.

[0009] Furthermore, the oil plug has an M12×1.5 external thread and a conical sealing structure with a sealing cone angle of 60°±5°.

[0010] Furthermore, the sealing structure for adding an oil plug also includes threaded seals or elastic sealing ring structures.

[0011] Furthermore, the cone angle of the sealing cone ranges from 55° to 65°, and the matching sealing gasket material is annealed copper or engineering plastic.

[0012] Furthermore, the input gear shaft is forged from 20CrMnTi alloy steel.

[0013] Furthermore, the diameter of the filling cavity gradually increases from the front end to the rear end, forming a transition structure that facilitates the flow of grease.

[0014] The beneficial effects of this utility model are as follows: Significantly improved maintenance efficiency: 1. This application adopts a tiered disassembly and assembly design. During maintenance, only the main reducer end cover and the oil filling plug need to be removed, without disassembling the drive motor, to expose the through filling chamber for lubrication. This design reduces the operation time per person by more than 60%, greatly shortens the maintenance cycle, and improves equipment uptime and utilization efficiency.

[0015] 2. Enhanced Sealing Reliability: A dual-redundant sealing system has been constructed. Anaerobic sealant is used at the end cover flange mating surface for static sealing, while a composite sealing structure of a conical surface and a gasket is used to form a dynamic seal when an oil plug is added. This combination effectively prevents grease leakage and the intrusion of external contaminants, ensuring the long-term stable operation of the transmission system.

[0016] 3. Optimized Maintenance Costs and Economy: Modular maintenance has been implemented. The oil plug, as an independent wear part, can be replaced individually, avoiding the need to replace large assemblies due to seal damage. At the same time, the simplified maintenance process reduces reliance on specialized tools and highly skilled technicians, significantly reducing maintenance costs and spare parts inventory costs.

[0017] 4. Anti-misoperation design enhances safety: The hexagonal head for removing the oil plug and the tool for removing the end cap are designed differently to physically prevent the possibility of accidentally removing the end cap or other critical connecting parts. This reduces the risk of equipment damage or seal failure due to incorrect operation and improves the safety and reliability of the maintenance process.

[0018] In summary, this utility model not only solves the problems of complex disassembly and assembly, low efficiency, and poor sealing reliability in the prior art, but also brings comprehensive and significant benefits in four aspects: improving efficiency, ensuring sealing, reducing costs, and preventing misoperation. Attached Figure Description

[0019] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a cross-sectional structural diagram of the input gear shaft of this utility model.

[0021] Figure 2 This is a cross-sectional structural diagram of the main reducer of this utility model. Detailed Implementation

[0022] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0023] See Figure 1 and Figure 2 The input gear shaft structure of this embodiment includes an input gear shaft 1, a filling chamber 2, an oil filling / draining plug 3, and a main reduction end cover 4.

[0024] The input gear shaft 1 is made of 20CrMnTi alloy steel through forging and precision machining, possessing excellent strength, toughness, and wear resistance. A through hole is machined at its axial center, forming a filling cavity 2. The front diameter of the filling cavity 2 is Φ8mm, and the rear diameter is Φ11mm, forming a transition tapered hole to facilitate smooth flow of grease from the rear to the front. The coaxiality of the filling cavity 2 and the outer circle of the input gear shaft 1 is precisely controlled, with an error not exceeding 0.01mm, ensuring that the dynamic balance performance of the shaft is not affected, while also guaranteeing that the minimum wall thickness on one side of the shaft is not less than 8mm, meeting strength requirements.

[0025] The rear opening of the filling chamber 2 is machined with internal threads. The removable filling / draining plug 3 is made of machined brass and has an M12×1.5 external thread for mating with the threaded hole at the rear end of the filling chamber 2. The end of the filling / draining plug 3 is designed with a 60° sealing cone angle (tolerance controlled within ±5°) and is equipped with an annealed copper sealing gasket. When the filling / draining plug 3 is tightened, the cone surface and the gasket form a reliable metal-to-metal contact seal, effectively preventing grease leakage. In addition, an appropriate amount of anaerobic thread-locking sealant can be applied to the threaded part to form a secondary sealing guarantee. The exposed end of the filling / draining plug 3 is a standard internal hexagonal structure, but its specifications (such as S10) are different from the specifications of the tool (such as S14) required to remove the main reduction end cap 4, forming a design to prevent misoperation.

[0026] The main reducer end cover 4 is fixed to the main reducer housing by bolts, and its flange mating surface is coated with anaerobic flat sealant for sealing.

[0027] The maintenance process is as follows: Preparation: Stop the vehicle and turn off the power to ensure safe operation.

[0028] Removing the end cover: Use the specific S14 socket tool to remove the bolts securing the main reducer end cover 4, carefully remove the end cover 4, and move it to a clean maintenance station. At this point, the drive motor does not need to be disassembled at all.

[0029] Remove the oil plug: Use an S10 Allen wrench to insert into the head of the oil plug 3, rotate it counterclockwise to loosen it from the rear end of the filling chamber 2 and remove it.

[0030] Adding grease: Align the nozzle of the high-pressure grease gun with the rear opening of filling chamber 2, and slowly and evenly inject high-temperature grease (such as lithium-based complex soap grease). Under pressure, the grease flows through filling chamber 2 to the spline engagement point between the external spline of the input shaft and the internal spline of the motor. Continue adding grease until a slight overflow of new grease is observed at the spline engagement point, indicating that the chamber is full and the old grease has been fully replaced.

[0031] Install the oil plug: Clean the residual grease from the port of filling chamber 2, put the new annealed copper gasket on the oil plug 3, and then use an S10 wrench to screw it into the threaded hole at the rear end of filling chamber 2, and apply the specified torque of 25 N·m-30 N·m to tighten it to ensure reliable conical surface sealing.

[0032] Install the end cap: Clean the main reducer end cap 4 and its mounting surface, apply new anaerobic sealant evenly to the end cap flange surface, then align it with the installation position, fix it with bolts, and tighten it in multiple steps in a diagonal sequence to the specified torque value (e.g., 80 N·m).

[0033] Inspection and cleaning: Check all mating surfaces for signs of grease leakage, clean the work site, and complete the maintenance.

[0034] The beneficial effects of this utility model embodiment have been verified in actual vehicle maintenance: the time for a single lubrication maintenance has been reduced from at least 90 minutes, which previously required disassembling the motor, to less than 30 minutes, improving efficiency by more than 60%; the double sealing structure did not show any leakage in bench vibration and temperature shock tests; and the anti-misoperation design effectively avoids the risk of on-site personnel accidentally disconnecting the motor wires.

[0035] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present utility model shall still fall within the scope of the technical solution of the present utility model.

Claims

1. An input gear shaft that facilitates grease filling, characterized in that: It includes an input gear shaft (1), which has a through filling cavity (2) at its axial center. The front end of the filling cavity (2) is connected to the cavity where the external spline of the input shaft connects to the internal spline of the motor, and the rear end is closed by a detachable oil filling plug (3).

2. The input gear shaft according to claim 1, characterized in that: The coaxiality error between the filling cavity (2) and the input gear shaft (1) is no greater than 0.01 mm.

3. The input gear shaft according to claim 1, characterized in that: The diameter of the filling cavity (2) is not less than Φ8mm, and the thickness of the shaft portion of the input gear shaft (1) on one side is not less than 8mm.

4. The input gear shaft according to claim 1, characterized in that: The oil plug (3) is provided with an M12×1.5 external thread and has a conical sealing structure with a sealing cone angle of 60°±5°.

5. The input gear shaft according to claim 4, characterized in that: The sealing structure of the oil plug (3) also includes a threaded seal or an elastic sealing ring structure.

6. The input gear shaft according to claim 4, characterized in that: The sealing cone angle ranges from 55° to 65°, and the matching sealing gasket is made of annealed copper or engineering plastic.

7. The input gear shaft according to any one of claims 1 to 6, characterized in that: The input gear shaft (1) is forged from 20CrMnTi alloy steel.

8. The input gear shaft according to any one of claims 1 to 6, characterized in that: The diameter of the filling cavity (2) gradually increases from the front end to the rear end, forming a transition structure that facilitates the flow of grease.

Images