Transmission system of hybrid bulldozer

Abstract

The utility model relates to a transmission system of a hybrid bulldozer, which belongs to the technical field of bulldozer driving and comprises an engine, a transfer case, an excitation synchronous generator, a rectification subsystem, a frequency conversion inversion subsystem, an asynchronous motor, a wet brake, a final drive and a power battery. The engine is connected to the input end of the final drive through the transfer case, the excitation synchronous generator, the rectification subsystem, the frequency conversion inversion subsystem, the asynchronous motor and the wet brake in sequence, and the output end of the final drive is connected to a crawler belt arranged on the bulldozer. The power battery is connected to the rectification subsystem. The utility model relates to an extended-range hybrid transmission system which is combined with a power battery to realize electric hybrid driving of a bulldozer and improve fuel economy of the bulldozer. And the device is not limited by factors such as manufacturing difficulty of a large gearbox and a hydraulic torque converter and highest pressure of a hydraulic element, a transmission system of the bulldozer is simplified, and the reliability of the whole bulldozer is effectively improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of bulldozer driving, and in particular relates to a transmission system of a hybrid bulldozer. Background Art

[0002] The transmission system (also known as the Drivetrain system in English) is the power system that generates driving force for the vehicle. The transmission system is generally composed of a clutch, a transmission, a universal joint, a final reducer, a differential and a half-axle. Its basic function is to transmit the power generated by the engine to the driving wheels of the vehicle, generate driving force, and enable the vehicle to travel at a certain speed.

[0003] Bulldozers are indispensable earth-moving machinery for large-scale national infrastructure, water conservancy and hydropower projects, mining, etc. They are mainly composed of a power system (transmission system), a cooling system, a chassis system, a working device, and a driving system. Different types of bulldozers have different transmission structures for their transmission systems. Specifically, when mechanical and hydraulic transmission bulldozers are working normally, the diesel engine burns diesel to generate power, and transmits the power to the crawler tracks through shock absorbers, torque converters, gearboxes, final drives and other components to drive the bulldozer forward, backward, and left and right to work. When a hydrostatic transmission bulldozer is working normally, the engine drives the travel hydraulic pump through the transfer case, and the travel hydraulic pump drives the travel motor, driving the hydrostatic bulldozer to realize the forward, backward, left and right steering functions. However, with the emergence of large-scale bulldozer equipment, the manufacturing difficulty of large gearboxes, torque converters and other transmission devices used in traditional mechanical and hydraulic transmission bulldozers has also increased, and their reliability is low, which seriously affects the large-scale development of bulldozers; hydrostatic transmission bulldozers are limited by the maximum pressure of hydraulic components, and it is impossible to manufacture ultra-high horsepower bulldozers; on the other hand, the transmission efficiency of mechanical and hydraulic transmission bulldozers and hydrostatic transmission bulldozers is low, which is not conducive to energy saving and consumption reduction of equipment. Utility Model Content

[0004] The purpose of the utility model is to provide a transmission system for a hybrid bulldozer to solve the problems existing in the prior art, that is, the traditional transmission mechanism in the prior art cannot realize a large-scale bulldozer, and even if a large-scale bulldozer can be realized, its transmission efficiency is not high and the reliability is low.

[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0006] A transmission system of a hybrid bulldozer comprises an engine, a transfer case, an excitation synchronous generator, a rectifier subsystem, a frequency conversion inverter subsystem, an asynchronous motor, a wet brake, a final drive and a power battery. The engine is connected to an input end of the final drive through the transfer case, the excitation synchronous generator, the rectifier subsystem, the frequency conversion inverter subsystem, the asynchronous motor and the wet brake in sequence, and an output end of the final drive is connected to a crawler configured on the bulldozer; the power battery is connected to the rectifier subsystem.

[0007] A further improvement of the technical solution is that it also includes a transmission accessory, and the transfer case is also connected to a hydraulic system working pump configured on the bulldozer through the transmission accessory.

[0008] A further improvement of the technical solution is that the working pump of the hydraulic system is installed at a reserved power take-off port configured on the transfer case.

[0009] A further improvement of the technical solution is that it also includes an auxiliary rectifier inverter subsystem, and the power battery is connected to the rectifier subsystem via the auxiliary rectifier inverter subsystem.

[0010] A further improvement of the technical solution is that the auxiliary rectifier inverter subsystem, the rectifier subsystem and the frequency conversion inverter subsystem are all installed on the left wing plate configured on the bulldozer.

[0011] Further improvements of the technical solution include high-voltage cables, wherein the excitation synchronous generator, the rectifier subsystem, the frequency conversion inverter subsystem and the asynchronous motor are all connected via high-voltage cables, and the rectifier subsystem, the auxiliary rectifier inverter subsystem and the power battery are all connected via high-voltage cables.

[0012] A further improvement of the technical solution is that it also includes a first shock absorber, and the engine and the transfer case are both installed on the front side of the main frame configured on the bulldozer through the first shock absorber.

[0013] A further improvement of the technical solution is that the excitation synchronous generator can be rigidly mounted on the transfer case, or mounted on the transfer case via a universal joint.

[0014] A further improvement of the technical solution is that the asynchronous motor is installed in a rear axle box of a main frame configured on the bulldozer, and is connected to the final drive through a spline and a stop flange.

[0015] The beneficial effect of the utility model is that the utility model forms an extended-range transmission system through an engine, a transfer case, an excitation synchronous generator, a rectifier subsystem, a frequency conversion inverter subsystem, an asynchronous motor, a wet brake and a final drive, and combines a power battery to form an extended-range hybrid power, thereby realizing electric hybrid power drive of the bulldozer, which can greatly improve the fuel economy of the bulldozer and reduce the use cost of the bulldozer; and the utility model is not limited by factors such as the difficulty in manufacturing large gearboxes and torque converters, the maximum pressure of hydraulic components, etc. The overall solution has strong feasibility, a simple system structure, a simplified bulldozer transmission system, and an increased degree of freedom in the arrangement of various components, thereby effectively improving the reliability of the entire machine.

[0016] In addition, the utility model has a reliable design principle, a simple structure and a very broad application prospect.

[0017] It can be seen that compared with the prior art, the present invention has outstanding substantive features and significant progress, and the beneficial effects of its implementation are also obvious. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the transmission system.

[0019] 110 is the engine, 120 is the transfer case, 131 is the excitation synchronous generator, 132 is the transmission accessories, 140 is the rectifier subsystem, 150 is the frequency conversion inverter subsystem, 160 is the asynchronous motor, 170 is the wet brake, 180 is the final drive, 191 is the power battery, and 192 is the auxiliary rectifier inverter subsystem. DETAILED DESCRIPTION

[0020] The traditional mechanical transmission bulldozer has a simple transmission structure, and the main power transmission route is engine-main clutch-gearbox-central transmission-final drive-crawler. It is an early bulldozer transmission form, which is characterized by full mechanical transmission and high transmission efficiency, but it is difficult to manufacture on a large scale. It is generally used in bulldozers below 200kW, and its operation and shifting are difficult, and it is difficult to drive. It is currently in a trend of being gradually eliminated; the transmission structure of the traditional hydraulic transmission bulldozer is similar to that of the mechanical transmission bulldozer, and the main power route is engine-shock absorber-hydraulic torque converter-gearbox-central transmission-final drive-crawler. It is the current mainstream bulldozer transmission form. After adding a hydraulic torque converter to the transmission system, on the one hand, it can greatly provide the low-speed torque of the power system, which is adapted to the low-speed and heavy-load conditions of the bulldozer. On the other hand, it can perform power shifting, improve the operating comfort, and facilitate the realization of intelligent control such as automatic actuation; but the disadvantage is that the hydraulic torque converter reduces The efficiency of the entire transmission system makes its fuel consumption high, and the manufacturing of transmission components such as high-power torque converters and gearboxes is difficult and costly. There are no suitable hydraulic transmission components for high-power bulldozers exceeding 800kW. Traditional hydrostatic transmission bulldozers use high-pressure oil for power transmission, and the main power transmission route is engine-transfer case-hydraulic pump-hydraulic motor-final drive-crawler. It is the mainstream form of bulldozers below 200kW. Its transmission route does not rely on mechanical structure and is arranged with flexible hydraulic hoses. It is flexible and convenient to install and easy to realize intelligence, automation and structural innovation. However, it is limited by the pressure resistance level of hydraulic components. The current maximum power intelligence can only reach 500kW level, and its transmission efficiency is low. Based on the limitation that the transmission systems of the above existing mechanical transmission bulldozers, hydraulic transmission bulldozers and hydrostatic transmission bulldozers cannot be developed on a large scale, the utility model provides a transmission system for a hybrid bulldozer.

[0021] The present invention will be described in detail below with reference to the accompanying drawings and through specific embodiments. The following embodiments are explanations of the present invention, but the present invention is not limited to the following implementation modes.

[0022] like Figure 1 As shown, the utility model provides a transmission system of a hybrid bulldozer, including an engine, a transfer case, an excitation synchronous generator, a rectifier subsystem, a frequency conversion inverter subsystem, an asynchronous motor, a wet brake, a final drive and a power battery. The engine is connected to the input end of the final drive through the transfer case, the excitation synchronous generator, the rectifier subsystem, the frequency conversion inverter subsystem, the asynchronous motor and the wet brake in sequence, and the output end of the final drive is connected to a crawler configured on the bulldozer; the power battery is connected to the rectifier subsystem.

[0023] Specifically, the excitation synchronous generator can be rigidly mounted on the transfer case, or mounted on the transfer case through a universal joint; the asynchronous motor is mounted in the rear axle box of the main frame configured on the bulldozer, and is connected to the final drive through a spline and a stop flange. In addition, the transmission system of the hybrid bulldozer also includes a first shock absorber, and the engine and the transfer case are both mounted on the front side of the main frame configured on the bulldozer through the first shock absorber.

[0024] In addition, the transmission system of the hybrid bulldozer also includes an auxiliary rectifier inverter subsystem and a high-voltage cable, and the power battery is connected to the rectifier subsystem through the auxiliary rectifier inverter subsystem; wherein the auxiliary rectifier inverter subsystem, the rectifier subsystem and the frequency conversion inverter subsystem are all installed on the left wing plate configured on the bulldozer for easy maintenance; the excitation synchronous generator, the rectifier subsystem, the frequency conversion inverter subsystem and the asynchronous motor are all connected through high-voltage cables, and the rectifier subsystem, the auxiliary rectifier inverter subsystem and the power battery are all connected through high-voltage cables to achieve the transmission of power flow between the components. The utility model introduces a power battery to realize the hybrid drive of the bulldozer, which can greatly improve the fuel economy of the bulldozer and reduce the use cost of the bulldozer; and by reasonably matching the driving and braking power flow of the bulldozer, as well as the capacity and charge and discharge rate of the power battery, energy recovery and reuse are achieved to improve the efficiency of the whole machine.

[0025] Finally, the transmission system of the hybrid bulldozer also includes transmission accessories, and the transfer case is also connected to the hydraulic system working pump configured on the bulldozer through the transmission accessories. The hydraulic system working pump is installed at the reserved power take-off port configured on the transfer case. When the engine is running, it synchronously drives the hydraulic system working pump to work, realizing the movement of the bulldozer blade, ripper and other working devices; the remaining components are arranged in the same structure as traditional bulldozers.

[0026] Specifically, the working principle of the transmission system of the hybrid bulldozer is as follows: during normal operation, the engine drives the excitation synchronous generator to rotate through the transfer case to generate three-phase AC power, the three-phase AC power is converted into 1000V-1500V DC power through the rectifier subsystem, and the DC power is converted into voltage and frequency controllable three-phase AC power through the frequency conversion inverter subsystem to drive the asynchronous motor to rotate, thereby driving the final drives on the left and right sides of the bulldozer to complete the movement of the whole machine; the forward and backward movement of the whole machine is achieved by controlling the direction of the excitation current of the asynchronous motor, and the left and right steering is achieved by detecting the left and right operating currents of the operating handle to control the power flow of the left and right drive motors to achieve electronic differential control.

[0027] When the whole machine is braked, the motor changes to a generator state, and the three-phase AC power generated is converted into 1000V-1500V DC power after passing through the frequency conversion inverter subsystem and the rectifier subsystem. The high-voltage DC power is converted into 600V DC power through the auxiliary rectifier inverter subsystem to charge the power battery, thereby realizing the bulldozer braking energy recovery; when the bulldozer is performing heavy-load bulldozer operations, the power of the power battery is converted from 600V DC power to 1000V-1500V DC power through the auxiliary rectifier inverter subsystem, and then merged with the rectified DC power generated by the generator to jointly drive the bulldozer to work in heavy load, thereby realizing the bulldozer hybrid drive; when the bulldozer is working normally, the speed generally does not exceed 10kW / h, and the braking conditions are relatively few. Through reasonable matching, a power battery with suitable capacity and charge and discharge rate is selected to keep the power of the power battery at 40%-60% at all times, thereby realizing hybrid power auxiliary drive and braking energy recovery, and the system is energy-saving and efficient.

[0028] The working pump of the related hydraulic system is driven by the transmission accessories on the transfer case; this solution is energy-efficient and efficient, and greatly improves the fuel economy of the bulldozer through energy recovery and reuse. It is also a new bulldozer extended-range electric drive structure, which simplifies the layout of the traditional bulldozer transmission structure and improves the layout freedom of each component. It is a good choice for the large-scale and energy-saving development of bulldozers. In addition, the working pump of the hydraulic system can also be driven by an independent electric motor to achieve intelligent control.

[0029] The above disclosure is only the preferred implementation mode of the utility model, but the utility model is not limited thereto. Any non-creative changes that can be thought of by technicians in this field, as well as several improvements and modifications made without departing from the principle of the utility model, should fall within the scope of protection of the utility model.

Claims

1. A transmission system for a hybrid bulldozer, characterized in that: It includes an engine, a transfer case, an excitation synchronous generator, a rectifier subsystem, a frequency conversion inverter subsystem, an asynchronous motor, a wet brake, a final drive and a power battery. The engine is connected to the input end of the final drive through the transfer case, the excitation synchronous generator, the rectifier subsystem, the frequency conversion inverter subsystem, the asynchronous motor and the wet brake in sequence, and the output end of the final drive is connected to the crawler configured on the bulldozer; the power battery is connected to the rectifier subsystem.

2. The transmission system of the hybrid bulldozer according to claim 1, characterized in that: It also includes transmission accessories, and the transfer case is also connected to a hydraulic system working pump configured on the bulldozer through the transmission accessories.

3. The transmission system of the hybrid bulldozer according to claim 2, characterized in that: The hydraulic system working pump is installed at the reserved power take-off port configured on the transfer case.

4. The transmission system of the hybrid bulldozer according to claim 1, characterized in that: It also includes an auxiliary rectifier inverter subsystem, through which the power battery is connected to the rectifier subsystem.

5. The transmission system of the hybrid bulldozer according to claim 4, characterized in that: The auxiliary rectifier inverter subsystem, the rectifier subsystem and the frequency conversion inverter subsystem are all installed on the left wing plate configured on the bulldozer.

6. The transmission system of the hybrid bulldozer according to claim 4, characterized in that: It also includes high-voltage cables. The excitation synchronous generator, rectifier subsystem, frequency conversion inverter subsystem and asynchronous motor are all connected by high-voltage cables. The rectifier subsystem, auxiliary rectifier inverter subsystem and power battery are all connected by high-voltage cables.

7. The transmission system of a hybrid bulldozer according to claim 1, characterized in that: The invention also comprises a first shock absorber, through which the engine and the transfer case are both mounted on the front side of a main frame arranged on the bulldozer.

8. The transmission system of a hybrid bulldozer according to claim 1, characterized in that: The excitation synchronous generator can be rigidly mounted on the transfer case or mounted to the transfer case via a universal joint.

9. The transmission system of a hybrid bulldozer according to claim 1, characterized in that: The asynchronous motor is installed in the rear axle box of the main frame configured on the bulldozer and is connected to the final drive through splines and stop flanges.

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