Electric drive system chassis structure and motor grader

Abstract

This invention discloses an electric drive transmission system chassis structure and a grader, belonging to the field of engineering machinery technology. It includes at least two drive axles, each equipped with an electric drive main reducer and a drive motor. One end of the electric drive main reducer is connected to the drive axle, and the other end is connected to the power end of the drive motor. Each of the two drive axles has symmetrically arranged wheel rims. A slewing support assembly is used to connect the chassis and the drive axles. This invention solves the problems of power line and power line height in traditional structures, and can effectively reduce weight and cost, improve driving comfort and maintenance convenience.

Description

Technical Field

[0001] This invention relates to an electric drive transmission system chassis structure and a grader, belonging to the field of engineering machinery transmission technology. Background Technology

[0002] With increasingly severe environmental and energy issues, major domestic and international construction machinery manufacturers are accelerating their transformation towards electrification and low-carbon technologies, leading to the widespread application of new energy technologies in motor graders. Traditional motor graders often use a balance box structure for their drive axles. This structure lacks a through-shaft, resulting in a low power line and chassis, but it is costly, heavy, and has a compact chassis. With the development and application of high-speed motors, electric drive axles are gradually evolving towards integration of a high-speed motor, gearbox, and drive axle. Integrated electric drive axles not only eliminate the power line height issue caused by through-shafts but also effectively reduce weight and cost. Currently, there are no compatible high-speed integrated electric drive systems and chassis solutions available for motor graders on the market.

[0003] The electrification of motor graders is still in its early stages. Traditional configurations are mostly driven by an engine or a low-speed, high-torque motor, connected to the drive axle via a drive shaft. To ensure the machine's center of gravity and output torque, the drive axle structure mostly adopts a balance box type. Its structure includes left and right balance boxes, axle housing section, slewing bearing, main reducer assembly, half shafts, planetary gear set, sprockets or gear train, and wheel-side output units. The input torque from the drive shaft is transmitted through the main reducer assembly, differential, half shafts, and planetary gear set to the center of the balance box, and then output to the wheel-side via the sprockets or gear train within the balance box.

[0004] Currently, grader chassis rely on the slewing support of the drive axle for load-bearing to ensure tire contact area and angle, lacking elastic shock absorption components, resulting in poor ride comfort. There are currently no dual-axle drive and chassis solutions available for graders on the market. With the application of high-speed integrated electric drive axles, this solution not only solves the problems of power line and power line height in traditional structures, but also effectively reduces weight and cost, improves driving comfort, and enhances maintenance convenience.

[0005] Disadvantages of existing technology: 1) It cannot use a through-type dual axle, resulting in a complex structure and difficult maintenance. Currently, the power chassis systems on the market adopt an electric drive route with low speed, high torque, and a balance box type drive axle, which is complex in structure and has poor maintenance convenience.

[0006] 2) Heavy weight, high cost, and poor versatility. Existing power chassis systems use low-speed, high-torque motors, which are heavy, costly, and lack advantages. Furthermore, traditional power chassis systems are almost impossible to make universally compatible with drive axles for graders of different horsepower.

[0007] 3) The chassis lacks elastic damping units, resulting in poor driving comfort. The traditional power chassis structure has a rigid direct connection between the drive axle and the frame, leading to a poor driving experience under road conditions. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the prior art and provide an electric drive transmission system chassis structure and grader, which adopts a dual high-speed integrated electric drive axle configuration. This not only solves the problems of power line and power line height in traditional structures, but also effectively reduces weight and cost, and improves driving comfort and maintenance convenience. To achieve the above objectives / to solve the above technical problems, the present invention is implemented using the following technical solution: First aspect: A chassis structure for an electric drive transmission system, comprising: At least two drive axles, each drive axle is equipped with an electric drive main reducer and a drive motor, one end of the electric drive main reducer is connected to the drive axle in a transmission connection, and the other end is connected to the power end of the drive motor; each of the two drive axles is symmetrically provided with wheel edges; A slewing support assembly for connecting the vehicle frame and the drive axle.

[0009] Optionally, the electric drive main reducer includes a first shaft, a second shaft, a third shaft, and a differential; the output end of the drive motor is connected to the first shaft, the first shaft is connected to the second shaft via a first-stage gear pair, and the second shaft is connected to the third shaft via a second-stage gear pair; the output end of the third shaft is connected to the input end of the differential, and the differential is connected to the wheel side via a half-shaft.

[0010] Optionally, each of the shafts is supported on the housing of the electric drive main reducer by bearings and oil seals.

[0011] Optionally, a parking brake is provided on the second shaft for braking the second shaft.

[0012] Optionally, the parking brake includes a brake caliper and a brake disc, the brake disc being mounted on the second shaft, and the brake caliper hydraulically driving the brake disc to achieve parking braking.

[0013] Optionally, the slewing support assembly includes a balance slewing bracket, a balance beam, ball joints, a thrust rod support, a thrust rod, and a damping unit. The balance slewing bracket and the thrust rod support are fixedly connected to the vehicle frame by bolts. The balance beam is hinged to the outside of the drive axle and the balance slewing bracket via ball joints, respectively, for bearing the vertical load of the entire vehicle. The two ends of the thrust rod are connected to the vehicle frame and the thrust rod support via ball joints, respectively, for transmitting driving and braking forces. One end of the damping unit is connected to the vehicle frame, and the other end is connected to a ball joint at one end of the balance beam.

[0014] Optionally, the damping unit includes a limiting block and a shock absorber, which are disposed in the connection area between the equalizer beam and the balance slewing bracket to mitigate driving impacts and vibrations.

[0015] Optionally, the drive axle is provided with an axle housing.

[0016] Optionally, an oil baffle is arranged inside the housing of the electric drive main reducer.

[0017] Second aspect: An engineering machinery, characterized in that it includes the electric drive transmission system chassis structure described in the first aspect.

[0018] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: 1) A high-speed integrated electric drive system and chassis for the grader were designed. The power chassis form of balanced suspension + integrated electric drive axle solves the pain point that traditional structures cannot use dual-axle structures - low chassis power line.

[0019] 2) It provides a dual-axle high-speed electric drive transmission system and chassis for graders, which solves the technical problems of existing balance box drive axles, such as large weight, high cost, complex structure, inconvenient maintenance, compact space layout, and poor versatility.

[0020] 3) The application of elastic damping units in the grader chassis system, with the drive axle and frame elastically connected, and the addition of components such as shock absorbers and buffer blocks, can effectively reduce the vibration of the machine and improve driving comfort. Attached Figure Description

[0021] Figure 1 Schematic diagram of the chassis of the electric drive transmission system of this invention; Figure 2 Schematic diagram of the electric drive main reducer structure of this invention; Figure 3 Schematic diagram of the slewing support component structure of the present invention; Figure 4 A dynamic schematic diagram of the high-speed integrated electric drive bridge of the grader of this invention.

[0022] In the diagram: 1. Electric drive main reducer; 2. Drive motor; 3. Axle housing; 4. Wheel rim; 5. Slewing support assembly; 6. Frame; 1-1. First axle; 1-2. Second axle; 1-3. Parking brake; 1-4. Bearing and oil seal; 1-5. Third axle; 1-6. Half axle; 1-7. Differential; 5-1. Shock absorber; 5-2. Limit block; 5-3. Thrust rod; 5-4. Thrust rod support; 5-5. Ball pin; 5-6. Equalizer beam; 5-7. Balance slewing support. Detailed Implementation

[0023] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0024] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0025] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" 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 will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0026] Example 1

[0027] like Figures 1-4 As shown, an electric drive transmission system chassis structure is disclosed, comprising: At least two drive axles, each drive axle is equipped with an electric drive main reducer 1 and a drive motor 2, one end of the electric drive main reducer 1 is connected to the drive axle in a transmission connection, and the other end is connected to the power end of the drive motor 2; each of the two drive axles is symmetrically provided with wheel edges 4; Slewing support assembly 5, which is used to connect the frame 6 and the drive axle; The dual high-speed integrated electric drive axle configuration not only solves the problems of power line and power line height in traditional structures, but also effectively reduces weight and cost, improves driving comfort and maintenance convenience, and allows for platform-based and modular design, increasing product versatility. The dual-axle structure simplifies the internal transmission mechanism of the balance box, significantly improving transmission efficiency and overall vehicle performance. Furthermore, the design of the frame-axle connection, with the slewing support component 5 providing elasticity, greatly enhances comfort compared to traditional grader chassis.

[0028] like Figure 2As shown, in this embodiment, the electric drive main reducer 1 includes a first shaft 1-1, a second shaft 1-2, a third shaft 1-5, and a differential 1-7. The output end of the drive motor is connected to the first shaft 1-1. The first shaft 1-1 is connected to the second shaft 1-2 via a first-stage gear pair, and the second shaft 1-2 is connected to the third shaft 1-5 via a second-stage gear pair. The output end of the third shaft 1-5 is connected to the input end of the differential 1-7, and the differential 1-7 is connected to the wheel rim 4 via a half-shaft 1-6. The electric drive main reducer 1 receives the speed and torque input from the drive motor 2 and outputs the motor's power to the wheel rim. The single-machine input power is reduced in speed and increased in torque through a three-stage reduction. Furthermore, in this embodiment, each shaft is supported on the housing of the electric drive main reducer 1 by bearings and oil seals 1-4.

[0029] like Figure 2 As shown, in this embodiment, a parking brake 1-3 is provided on the second shaft 1-2 for braking the second shaft 1-2. The parking brake 1-3 includes a brake caliper and a brake disc. The brake disc is mounted on the second shaft 1-2 and can achieve parking braking under hydraulic action. At the same time, an oil baffle is arranged inside the housing of the electric drive main reducer 1 to reduce the oil churning power and lower the temperature rise.

[0030] like Figure 2 As shown, in this embodiment, the slewing support assembly 5 includes a balance slewing bracket 5-7, a balance beam 5-6, ball pins 5-5, a thrust rod support 5-4, a thrust rod 5-3, and a shock absorption unit. The balance slewing bracket 5-7 and the thrust rod support 5-4 are fixedly connected to the frame with bolts. The balance beam 5-6 is hinged to the axle housing 3 and the balance slewing bracket 5-7 respectively through ball pins 5-5, and is the load-bearing mechanism between the frame and the drive axle, used to bear the weight of the entire machine. The balance beam 5-6 can be an inelastic connection mechanism or a leaf spring with elasticity. The two ends of the thrust rod 5-3 are connected to the frame and the thrust rod support 5-4 respectively through ball pins 5-5, used to transmit driving force and braking force. One end of the shock absorption unit is connected to the frame 6, and the other end is connected to the ball pin 5-5 at one end of the balance beam 5-6.

[0031] Furthermore, the shock absorption unit includes a limiting block 5-2 and a shock absorber 5-1. The limiting block 5-2 and the shock absorber 5-1 are located in the connection area between the equalizing beam 5-6 and the balance slewing bracket 5-7 to alleviate impacts and vibrations during driving. Specifically, one end of the shock absorber 5-1 is connected to the frame 6, and the other end is connected to the ball pin 5-5. The limiting block 5-2 is located on the frame 6 to limit the compression space between the equalizing beam 5-6 and the frame, thereby limiting the compression of the shock absorber.

[0032] The high-speed integrated electric drive transmission system for the grader has the following torque transmission route: high-speed motor input → electric drive main reducer → differential → half shaft → wheel-side sun gear → planetary gears → planetary carrier → wheel hub → tire. The electric drive main reducer 1 features a large speed ratio to match the high-speed, low-torque motor, and its structure can be either a planetary gear reducer or a gear pair reducer. The application of high-speed integrated electric drive technology not only solves the problems of power line and power line height in traditional structures but also effectively reduces weight and cost by reducing the size of the motor.

[0033] This invention designs a high-speed integrated electric drive system and chassis for a grader. It adopts a power chassis form of balanced suspension + dual-axle integrated electric drive, which not only solves the problem of high power line of traditional through-type dual-axle chassis, but also solves the technical problems of existing balanced box drive axles such as large weight, high cost, complex structure, inconvenient maintenance, compact space layout and poor versatility.

[0034] 2) The chassis is equipped with an elastic damping system unit, which is applied to the grader chassis system. The drive axle is elastically connected to the frame. The addition of components such as shock absorbers and buffer blocks can effectively reduce the vibration of the machine and improve driving comfort.

[0035] Example 2

[0036] A motor grader is disclosed, including the electric drive transmission system chassis structure described in Embodiment 1. The high-speed integrated electric drive chassis of the motor grader, i.e., the movement path of the slewing support assembly during the motor grader's operation, is as follows... Figure 4 As shown, on uneven road surfaces, the rotation of the balance beam can be used to maintain the contact area and angle of the wheels, and the shock absorption unit can be used to reduce the feeling of bumps and improve smoothness, so as to ensure traction and stability in complex and harsh environments.

[0037] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A chassis structure for an electric drive transmission system, characterized in that, include: At least two drive axles, each drive axle is equipped with an electric drive main reducer (1) and a drive motor (2), one end of the electric drive main reducer (1) is connected to the drive axle in transmission, and the other end is connected to the power end of the drive motor (2); each of the two drive axles is symmetrically provided with wheel edges (4). Slewing support assembly (5), which is used to connect the frame (6) and the drive axle.

2. The chassis structure of the electric drive transmission system according to claim 1, characterized in that, The electric drive main reducer (1) includes a first shaft (1-1), a second shaft (1-2), a third shaft (1-5), and a differential (1-7); the output end of the drive motor (2) is connected to the first shaft (1-1), the first shaft (1-1) is connected to the second shaft (1-2) through a first-stage gear pair, the second shaft (1-2) is connected to the third shaft (1-5) through a second-stage gear pair; the output end of the third shaft (1-5) is connected to the input end of the differential (1-7), and the differential (1-7) is connected to the wheel rim (4) through a half-shaft (1-6).

3. The chassis structure of the electric drive transmission system according to claim 2, characterized in that, Each of the shafts is supported on the housing of the electric drive main reducer by bearings and oil seals (1-4).

4. The chassis structure of the electric drive transmission system according to claim 2, characterized in that, A parking brake (1-3) is provided on the second shaft (1-2) for braking the second shaft (1-2).

5. The chassis structure of the electric drive transmission system according to claim 4, characterized in that, The parking brake (1-3) includes a brake caliper and a brake disc. The brake disc is mounted on the second shaft (1-2). The brake caliper hydraulically drives the brake disc to achieve parking braking.

6. The chassis structure of the electric drive transmission system according to claim 1, characterized in that, The slewing support assembly (5) includes a balance slewing bracket (5-7), a balance beam (5-6), a ball pin (5-5), a thrust rod support (5-4), a thrust rod (5-3), and a damping unit; the balance slewing bracket (5-7) and the thrust rod support (5-4) are fixedly connected to the vehicle frame; the balance beam (5-6) is hinged to the outside of the drive axle and the balance slewing bracket (5-7) respectively through the ball pin (5-5) to bear the vertical load of the whole vehicle; the two ends of the thrust rod (5-3) are connected to the vehicle frame and the thrust rod support (5-4) respectively through the ball pin (5-5) to transmit driving force and braking force; one end of the damping unit is connected to the vehicle frame (6), and the other end is connected to the ball pin (5-5) at one end of the balance beam (5-6).

7. The chassis structure of the electric drive transmission system according to claim 6, characterized in that, The damping unit includes a limiting block (5-2) and a damper (5-1). The limiting block (5-2) and the damper (5-1) are located in the connection area between the balance beam (5-6) and the balance slewing bracket (5-7) to mitigate driving impact and vibration.

8. The chassis structure of the electric drive transmission system according to claim 1, characterized in that, The drive axle is provided with an axle housing (3).

9. The chassis structure of the electric drive transmission system according to claim 1, characterized in that, An oil baffle is arranged inside the housing of the electric drive main reducer (1).

10. A grader, characterized in that, The chassis structure of the electric drive transmission system as described in any one of claims 1-9.

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