A layout structure of a bulldozer electric drive system and the bulldozer

Abstract

This invention provides an arrangement structure for a bulldozer transmission system and a bulldozer, belonging to the field of electric drive bulldozers. The power unit of the electric drive system is mounted on the main frame at the front of the rear axle housing; the rectifier of the electric drive system is mounted on the rear end face of the rear axle housing, with its input and output ends facing downwards; the high-voltage cable leading from the output end of the power unit passes through a pre-set flange on the rear axle housing, enters the rear axle housing, then runs along the outer surface of the drive drum, and finally connects to the input end of the rectifier. This invention arranges the rectifier on the rear end face of the rear axle housing, making daily inspection and troubleshooting of the rectifier convenient and quick; furthermore, the high-voltage cable between the power unit and the rectifier is hidden inside the rear axle housing, and the independent wiring arrangement simplifies the wiring structure, avoiding signal interference and maintenance difficulties caused by messy wiring.

Description

Technical Field

[0001] This invention relates to an arrangement structure of a bulldozer transmission system and a bulldozer, belonging to the field of electric drive bulldozers. Background Technology

[0002] Currently, tracked bulldozers generally use a hydraulic-mechanical transmission system. However, this system suffers from drawbacks such as low transmission efficiency, high noise levels, high fuel consumption, frequent driver intervention, and high labor intensity. Furthermore, due to the compact structure of bulldozers, the installation of traditional torque converters, gearboxes, and central transmissions is complex, requiring sophisticated assembly processes, resulting in limited improvements in assembly efficiency and a high failure rate. While hydrostatic transmission is simpler to install than hydraulic-mechanical transmission, it also suffers from high system failure rates, cumbersome assembly, and complex assembly processes. Therefore, it is difficult to meet the evolving needs of society and the ever-increasing demands of users.

[0003] In recent years, the trend of large-scale and green development of construction machinery has been of great significance to the development of the national economy. The application of electric drive bulldozers has simplified the original bulldozer transmission system, which was originally complex to install, had high assembly process requirements, and had a high failure rate. With the development of new energy, electric drive has emerged. Bulldozers using electric drive can save fuel and reduce emissions. Electric drive transmission has fast power response, strong climbing ability, stepless speed regulation, smooth operation, and the engine can operate stably under economic conditions. It is simple to operate, safe and reliable to drive, and has good economic benefits.

[0004] However, the transmission devices of existing electric drive bulldozers adopt a decentralized layout, which has the following drawbacks:

[0005] (1) The decentralized layout makes the space scattered and messy, with poor overall coordination and a large space occupation;

[0006] (2) Due to the limitations of the traditional bulldozer structure, without a system layout, there is a problem of "one layout for each vehicle", which is prone to failure and increases the difficulty of maintenance;

[0007] (3) Unlike hydraulic-mechanical transmission, electric transmission devices contain high-voltage wiring harnesses. Failure to implement a system layout will reduce the safety of vehicle use. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the prior art and provide an arrangement structure for the electric drive system of a bulldozer and a bulldozer. By systematically arranging and wiring the electric drive system of the bulldozer, the problems of the existing scattered and messy space, poor overall coordination, and high maintenance difficulty are solved.

[0009] To achieve the above objectives, the present invention is implemented using the following technical solution:

[0010] In a first aspect, the present invention provides an arrangement structure for an electric drive system for a bulldozer, wherein the power unit of the electric drive system is mounted on the main frame on the front side of the rear axle housing; the rectifier of the electric drive system is mounted on the rear end face of the rear axle housing, with its input and output ends facing downwards; the high-voltage cable led out from the output end of the power unit passes through a pre-set flange on the rear axle housing and enters the rear axle housing, then is arranged along the outer surface of the drive drum, and finally connects to the input end of the rectifier.

[0011] In conjunction with the first aspect, optionally, the power unit includes: an engine, a transfer case, and a generator; the generator is disposed between the rear axle housing and the engine, and the transfer case is disposed between the generator and the engine; the output end of the generator faces the rectifier; the fuel tank of the engine is mounted above the bulldozer rear axle housing, located behind one side wing.

[0012] In conjunction with the first aspect, optionally, the output end of the rectifier of the electric drive system is connected to the inverter of the electric drive system; the high-voltage cable led out from the output end of the inverter passes through a pre-set flange on the drive drum and enters the interior of the drive drum, and is connected to the traction device of the electric drive system.

[0013] In conjunction with the first aspect, optionally, the inverter device includes: a first inverter cabinet and a second inverter cabinet; the first inverter cabinet is stacked on the rear side of the rectifier device with its input and output terminals facing downwards, and the second inverter cabinet is installed on the bottom surface of the rear axle housing with its input and output terminals facing the rear of the bulldozer.

[0014] In conjunction with the first aspect, optionally, the traction device of the electric drive system includes: a first traction motor and a second traction motor; the first traction motor and the second traction motor are arranged inside the drive drum.

[0015] In conjunction with the first aspect, optionally, the braking resistor of the electric drive system includes: a first braking resistor connected in parallel across the first inverter cabinet and a second braking resistor connected in parallel across the second inverter cabinet; the first braking resistor and the second braking resistor are installed on one side wing plate of the bulldozer.

[0016] In conjunction with the first aspect, optionally, the cooling device of the electric drive system is powered by a DC / DC converter connected in parallel to the output cable of the rectifier; the DC / DC converter is mounted on the engine's fuel tank.

[0017] In a second aspect, the present invention provides a bulldozer, comprising: an electric drive system, wherein the electric drive system adopts the arrangement structure of the bulldozer electric drive system as described in the first aspect.

[0018] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0019] (1) The arrangement structure of the bulldozer electric drive system provided by the present invention allows the high-voltage cable of the three-phase AC power from the power unit to be passed through a preset flange into the rear axle box, and then laid along the outer surface of the drive drum through a fixing member. Then it passes out from the open area of ​​the rear axle box and is connected to the input end of the rectifier installed on the rear end face of the rear axle box. In order to facilitate wiring and simplify the layout, the input and output ports of the rectifier are set to face downward. This arrangement structure of placing the rectifier on the rear end face of the rear axle box makes the maintenance of the rectifier convenient and quick. In addition, the high-voltage cable between the power unit and the rectifier is hidden inside the rear axle box. The independent wiring arrangement simplifies the wiring structure and avoids signal interference caused by messy lines.

[0020] (2) The layout structure of the electric drive system for bulldozer provided by the present invention arranges the inverter and the rectifier in one place, which not only shortens the wiring length of the high voltage cable, but also facilitates the daily inspection and fault repair of the bulldozer.

[0021] (3) The layout structure of the electric drive system for bulldozers provided by the present invention arranges the traction device inside the drive drum. On the one hand, the drive drum increases the strength of the structure, and on the other hand, the cable led out by the inverter device is directly connected to the inside of the drive drum through the preset flange on the drive drum, making the circuit layout more concise. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the electric drive system for a bulldozer provided in Embodiment 1 of the present invention;

[0023] Figure 2 This is a schematic diagram of the layout structure of the bulldozer electric drive system provided in Embodiment 1 of the present invention;

[0024] Figure 3 This is a schematic diagram of the arrangement of the high-voltage cable between the power unit and the rectifier provided in Embodiment 1 of the present invention;

[0025] Figure 4 This is a schematic diagram showing the positions of the rectifier and inverter provided in Embodiment 2 of the present invention;

[0026] Figure 5 This is a wiring diagram of the rectifier and inverter provided in Embodiment 2 of the present invention;

[0027] In the diagram: 11—Engine, 12—Transfer case, 13—Generator, 2—Rear axle case, 3—Rectifier, 4—First inverter cabinet, 5—Second inverter cabinet, 6—Flange 1, 7—Flange 2. Detailed Implementation

[0028] The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus. The technical solutions of the embodiments of this application will now be clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Example 1

[0029] This embodiment provides an arrangement structure for a bulldozer's electric drive system, such as... Figure 1 and Figure 2 As shown, the power unit of the electric drive system is installed on the front main frame of the rear axle housing 2; the rectifier 3 of the electric drive system is installed on the rear end face of the rear axle housing 2.

[0030] Specifically, the power unit is used to generate three-phase alternating current, such as Figure 2 As shown, the system includes an engine 11, a transfer case 12, and a generator 13 arranged in sequence. The engine 11 is mounted at the front of the bulldozer's main frame, and its fuel tank is mounted above the rear axle housing 2, located behind one side wing plate. The generator 13 is located between the rear axle housing 2 and the engine 11. The engine 11 is connected to the generator 13 through the transfer case 12, which is located between the generator 13 and the engine 11. The output end of the generator 13 faces the rectifier. The output line of the generator 13 needs to be connected to the rectifier 3, which converts the three-phase AC power into DC bus voltage to power the traction motor.

[0031] To simplify the wiring layout, the rectifier 3 installed on the rear end face of the rear axle housing 2 is configured with its input and output terminals facing downwards, such as... Figure 2 and Figure 3 As shown, to facilitate the connection of the generator 13 output line to the rectifier 3, the output line direction of the generator 13 is set towards the location of the rear axle housing 2, that is, the rear of the bulldozer. The high-voltage cable led out from the output end of the generator 13 first enters the rear axle housing 2 through the pre-set flange 2 7 on the rear axle housing 2, then is arranged along the outer surface of the drive drum, passes over the drive drum and is arranged downward, and then passes out from the open opening of the rear axle housing 2, and finally connects to the input end of the rectifier 3.

[0032] This concealed, independent wiring arrangement allows the high-voltage cable between the generator 13 and the rectifier 3 to be routed inwards from the rear axle via a dedicated flange, eliminating interference and enhancing line stability. Example 2

[0033] Based on Example 1, this example provides the arrangement structure between the rectifier, inverter, and traction motor in the electric drive system of a bulldozer.

[0034] In some specific embodiments, the traction motor is a permanent magnet synchronous motor, and the DC bus voltage output by the rectifier is converted by the inverter to power the traction motor.

[0035] The output end of the rectifier of the electric drive system is connected to the inverter of the electric drive system. The inverter adjusts the voltage of the traction motors on both sides of the bulldozer according to the load requirements. The high-voltage cable led out from the output end of the inverter passes through the pre-set flange on the drive drum and enters the interior of the drive drum, connecting to the traction device of the electric drive system.

[0036] In some specific embodiments, the inverter device includes: a first inverter cabinet 4 and a second inverter cabinet 5.

[0037] like Figure 4 As shown, the first inverter cabinet 4 is stacked on the rear side of the rectifier, with its input and output terminals facing downwards, and the second inverter cabinet 5 is installed on the bottom surface of the rear axle box 2, with its input and output terminals facing the rear of the bulldozer.

[0038] like Figure 5 As shown, the high-voltage cables leading from the output terminal of rectifier 3 are connected to the input terminals of the first inverter cabinet 4 and the second inverter cabinet 5, respectively. The DC bus voltage is supplied to the first inverter cabinet 4 and the second inverter cabinet 5 for inversion and conversion, respectively.

[0039] The first inverter cabinet 4 and the second inverter cabinet 5, along with the rectifier 3, are centrally located at the rear of the rear axle box. This not only saves machine space but also facilitates daily machine inspection and troubleshooting.

[0040] In some specific embodiments, the rectifier 3 is mounted on the rear end face of the rear axle housing via a mounting bracket with a shock absorber, and / or the second inverter cabinet 5 is mounted on the bottom surface of the rear axle housing via a mounting bracket with a shock absorber.

[0041] The traction device of the electric drive system includes: a first traction motor and a second traction motor, which are respectively installed on both sides of the bulldozer and arranged inside the drive drum; the first traction motor is connected to the first inverter cabinet 4, and the second traction motor is connected to the second inverter cabinet 5.

[0042] like Figure 5As shown, the high-voltage cables leading from the output terminals of the first inverter cabinet 4 and the second inverter cabinet 5 pass through the pre-set flange 6 on the drive drum and enter the interior of the drive drum, respectively connecting to the corresponding first traction motor and second traction motor.

[0043] In some specific embodiments, the braking resistor of the electric drive system includes a first braking resistor connected in parallel across the first inverter cabinet 4 and a second braking resistor connected in parallel across the second inverter cabinet 5. The first braking resistor and the second braking resistor are installed on one side wing plate of the bulldozer.

[0044] It should be noted that the function of the braking resistor in the electric drive system is:

[0045] 1. When using electric braking, the negative torque applied to the traction motor will generate a reverse electromotive force; in order to prevent the high-voltage components on the busbar from burning out, it needs to be dissipated as heat.

[0046] 2. When the bulldozer starts up, the excessive power will cause a brief overshoot of the bus voltage. At this time, the braking resistor acts as a safety resistor to suppress the overshoot of the bus voltage.

[0047] The heat dissipation device of the electric drive system is powered by a DC / DC converter connected in parallel to the output cable of the rectifier.

[0048] In some specific embodiments, the heat dissipation device is a fan for cooling the first braking resistor and the second braking resistor.

[0049] In some specific embodiments, the heat dissipation device is a water pump for cooling the electric drive system.

[0050] In some embodiments with a fan or water pump, the fan or water pump is powered by a DC / DC converter connected in parallel to the output cable of the rectifier; the DC / DC converter is mounted on the fuel tank of the engine 11. Example 3

[0051] This embodiment provides a bulldozer, including: an electric drive system, wherein the electric drive system adopts the arrangement structure of the bulldozer electric drive system as described in Embodiment 1 or Embodiment 2.

[0052] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. An arrangement structure for an electric drive system of a bulldozer, characterized in that, The power unit of the electric drive system is mounted on the main frame on the front side of the rear axle housing. The rectifier of the electric drive system is installed on the rear end face of the rear axle housing, with its input and output terminals facing downwards; The high-voltage cable leading from the output end of the power unit passes through the pre-set flange on the rear axle housing and enters the rear axle housing. It then runs along the outer surface of the drive drum and finally connects to the input end of the rectifier.

2. The layout structure of the bulldozer electric drive system according to claim 1, characterized in that, The power unit includes: an engine, a transfer case, and a generator; the generator is disposed between the rear axle housing and the engine, and the transfer case is disposed between the generator and the engine; the output end of the generator faces the rectifier. The engine's fuel tank is mounted above the bulldozer's rear axle housing, located behind one side wing.

3. The layout structure of the bulldozer electric drive system according to claim 1, characterized in that, The output end of the rectifier of the electric drive system is connected to the inverter of the electric drive system; the high-voltage cable led out from the output end of the inverter passes through the pre-set flange on the drive drum and enters the interior of the drive drum, and is connected to the traction device of the electric drive system.

4. The layout structure of the bulldozer electric drive system according to claim 3, characterized in that, The inverter device includes: a first inverter cabinet and a second inverter cabinet; the first inverter cabinet is stacked on the rear side of the rectifier device with its input and output terminals facing downwards, and the second inverter cabinet is installed on the bottom surface of the rear axle box with its input and output terminals facing the rear of the bulldozer.

5. The layout structure of the bulldozer electric drive system according to claim 4, characterized in that, The rectifier and / or the second inverter cabinet are mounted on the corresponding position on the rear axle box via a mounting bracket with a shock absorber.

6. The layout structure of the bulldozer electric drive system according to claim 3, characterized in that, The traction device of the electric drive system includes: a first traction motor and a second traction motor; the first traction motor and the second traction motor are arranged inside the drive drum.

7. The layout structure of the bulldozer electric drive system according to claim 4, characterized in that, The braking resistor of the electric drive system includes a first braking resistor connected in parallel across the first inverter cabinet and a second braking resistor connected in parallel across the second inverter cabinet; the first braking resistor and the second braking resistor are installed on one side wing plate of the bulldozer.

8. The layout structure of the bulldozer electric drive system according to claim 2, characterized in that, The cooling device of the electric drive system is powered by a DC / DC converter connected in parallel to the output cable of the rectifier; the DC / DC converter is mounted on the engine's fuel tank.

9. A bulldozer, comprising: An electric drive system, characterized in that the electric drive system adopts the arrangement structure as described in any one of claims 1-8.

Images