A forced cooling hydraulic system for scraper

Abstract

The invention discloses a forced cooling hydraulic system for a scraper, comprising a front axle and a rear axle, wherein the outlets of the forced cooling assemblies of the front axle and the rear axle are respectively connected to an oil suction filter, a dosing pump, a high-pressure filter and an oil radiator in sequence, and the outlets of the oil radiators are respectively connected to the inlets of the forced cooling assemblies of the front axle and the rear axle, so that the oil in the forced cooling assemblies of the front axle and the rear axle is filtered once by the oil suction filter, filtered twice by the high-pressure filter and cooled by the oil radiator, and then returns to the forced cooling assembly to form a closed loop. The forced cooling hydraulic system of the invention separates the forced cooling hydraulic system of the scraper from the hydraulic system of the vehicle as a whole, and provides an independent cooling circuit to reduce the risk of contamination of the hydraulic system of the whole machine.

Description

Technical Field

[0001] The invention belongs to the technical field of engineering machinery, and in particular relates to a forced cooling hydraulic system for a scraper. Background Art

[0002] During vehicle operation, axles, especially heavy-duty axles, will generate a lot of heat due to heavy loads, long-term continuous operation, and frequent braking. If this heat cannot be dissipated in time, the axle temperature will rise sharply. High temperature will have many adverse effects on various parts of the axle, such as reducing the performance of lubricants, accelerating the aging of seals, affecting the life of key components such as bearings, and may even cause axle failures, affecting the driving safety and reliability of the vehicle.

[0003] The existing axle cooling systems are mainly divided into two types: dry / wet axle natural air cooling and wet axle hydraulic cooling. Among them, the dry / wet axle natural air cooling has the disadvantages of low natural cooling efficiency and air cooling system limitations:

[0004] a. Low efficiency of natural cooling: The traditional cooling method that relies on natural convection of air often cannot meet the heat dissipation requirements for some high-load axles. The speed of natural cooling is slow, and it is difficult to effectively control the axle temperature within a reasonable range in hot environments or when the vehicle is heavily loaded or driving at high speed.

[0005] b. Limitations of air cooling system: Although the air cooling system can improve the cooling effect to a certain extent, there are also some problems. For example, the air cooling system is greatly affected by the ambient temperature and wind speed. In harsh working environments, such as sand and dust, high temperature and high humidity, the cooling effect of the air cooling system will be greatly reduced.

[0006] In comparison, the wet bridge hydraulic cooling system has the advantages of efficient heat dissipation, strong integration and adaptability:

[0007] a. Efficient heat dissipation: The hydraulic cooling system can transport cooling oil to the radiator inside the wet axle through an oil pump, and use the radiator to exchange heat with the outside air, thereby achieving efficient heat dissipation.

[0008] b. Strong integration: The hydraulic cooling system can be integrated with other hydraulic systems of the vehicle.

[0009] c. Strong adaptability: The hydraulic cooling system can adapt to different working environments and working conditions. Whether in harsh environments such as high temperature, high humidity, dust, or under heavy load, high-speed driving and other working conditions, the hydraulic cooling system can maintain a good cooling effect and ensure the normal operation of the wet axle.

[0010] However, when the existing wet bridge forced cooling hydraulic system is integrated with the vehicle's complete hydraulic system, since the wet bridge forced cooling system usually uses coolant to reduce the temperature of the bridge body, during long-term operation, the coolant may penetrate into the hydraulic system through poorly sealed interfaces or damaged components, seriously polluting the cleanliness of the hydraulic oil in the vehicle's complete hydraulic system. At the same time, the bridge body operates under high temperature and high load conditions, and the friction of the friction plates in the bridge brake may produce iron filings. These particles enter the hydraulic system through the circulation of the cooling system, which can easily pollute the cleanliness of the hydraulic oil and cause the pump and valve components in the hydraulic system to become stuck and damaged. The existing forced cooling hydraulic system is equipped with a separate forced cooling hydraulic oil tank to form an open hydraulic system. It is necessary to set up a separate hydraulic oil tank and add additional parts, which not only takes up maintenance space, but also requires additional maintenance components. Summary of the invention

[0011] In view of the above-mentioned defects, the present invention provides a forced cooling hydraulic system for a scraper loader, which separates the forced cooling hydraulic system for the scraper loader from the hydraulic system of the vehicle, and makes the cooling circuit independent to reduce the risk of iron filings generated by the friction of the friction plate inside the bridge brake contaminating the hydraulic oil of the hydraulic system.

[0012] Technical solution:

[0013] A forced cooling hydraulic system for a scraper comprises a front axle and a rear axle, wherein the outlets of the forced cooling assemblies of the front axle and the rear axle are respectively connected to an oil suction filter, a metering pump, a high-pressure filter and an axle oil radiator in sequence, and the outlets of the axle oil radiator are respectively connected to the inlets of the forced cooling assemblies of the front axle and the rear axle, so that the axle oil in the forced cooling assemblies of the front axle and the rear axle is filtered once by the oil suction filter, filtered twice by the high-pressure filter and cooled by the axle oil radiator, and then returns to the forced cooling assembly to form a closed loop.

[0014] Preferably, a joint block is provided at the inlet and outlet of the front and rear axle forced cooling assemblies as a connecting hub, the bottom of the front and rear axle forced cooling assemblies are connected to the C3 and C2 interfaces of the joint block, the top is connected to the B3 and B2 interfaces of the joint block, the hydraulic cylinder in the bridge is connected to the A3 and A2 interfaces of the joint block, the inlet of the metering pump is connected to the C3 and C2 interfaces of the joint block, and the outlet of the bridge oil radiator is connected to the B3 and B2 interfaces of the joint block.

[0015] Preferably, a bypass check valve is disposed inside the oil suction filter, and both ends of the bypass check valve are connected to the connector block and the metering pump. When the oil suction filter is clogged, the bridge oil can be sucked out by the metering pump through the bypass check valve.

[0016] Preferably, the metering pump is equipped with a safety valve, which is arranged between the outlet of the oil suction filter and the inlet of the high-pressure filter. After the metering pump sucks out the bridge oil, it is equipped with a safety valve. If the subsequent pipeline and the one-way valve are blocked, the bridge oil can flow back to the pump's oil suction port through the safety valve, preventing the metering pump and other components from being damaged by excessive pressure.

[0017] Preferably, a bypass check valve and a pressure alarm switch are configured inside the high-pressure filter. The two ends of the bypass check valve are connected between the outlet of the metering pump and the inlet of the bridge oil radiator. The pressure alarm switch collects the bridge oil pressure difference information. When the pressure exceeds the threshold of the pressure alarm switch, the entire vehicle alarms.

[0018] As a preferred option, hydraulic switches are installed in the forced cooling assemblies of the front and rear axles. When leakage occurs in the pipelines and components, the oil level in the axle becomes low, which is insufficient to control the transmission oil temperature in the axle within the optimal range, an alarm is triggered, and the entire vehicle is shut down, thereby protecting the axle and various components of the cooling hydraulic system.

[0019] Preferably, the forced cooling hydraulic system also includes a controller and a bridge oil temperature sensor, wherein the bridge oil temperature sensor is arranged at the outlet of the bridge oil radiator and is electrically connected to the controller; the metering pump is driven by a motor, and the motor is electrically connected to the controller; the controller controls the motor speed according to the bridge oil temperature after heat dissipation, forming a feedback closed-loop control.

[0020] The present invention also discloses a working method of a forced cooling hydraulic system for a scraper loader. Based on the above-mentioned forced cooling hydraulic system for a scraper loader, a motor drives a quantitative pump to suck axle oil out of the forced cooling assembly of the front axle and / or the rear axle, an oil suction filter filters a part of impurities, and then the impurities not filtered out by the oil suction filter are filtered for a second time through a high-pressure filter. The filtered axle oil is dissipated through a radiator and then returned to the forced cooling assembly of the front and / or rear axle through a joint block.

[0021] Preferably, the oil suction filter and / or the high-pressure filter is provided with a bypass valve inside, and when the oil suction filter and / or the high-pressure filter is clogged, the bridge oil passes through the bypass one-way valve.

[0022] Preferably, when the metering pump is equipped with a safety valve, when the downstream pipeline of the metering pump is blocked, the bridge oil flows back to the oil suction port of the pump through the safety valve, thereby preventing the metering pump and other components from being damaged by excessive pressure.

[0023] The beneficial effects of the present invention are:

[0024] (1) The forced cooling hydraulic system of the scraper disclosed in the present invention separates the forced cooling hydraulic system of the scraper from the hydraulic system of the vehicle, which can minimize the pollution effect of iron filings in the bridge brake on other hydraulic systems of the vehicle.

[0025] The present invention configures the front axle and the rear axle with independent forced cooling hydraulic systems, and sets a filter for filtering iron chips generated by friction of the friction plate in the axle brake to reduce the pollution effect of iron chips on the hydraulic systems of the front and rear axles, and the front axle and the rear axle are independent and do not affect their respective cooling and the liquid level of the axle oil;

[0026] (2) The forced cooling hydraulic system for scrapers disclosed in the present invention can adjust the operating temperature range of the components in the bridge by monitoring the temperature of the bridge oil, forming a feedback closed-loop control, so that all components in the bridge are within the optimal working range, thereby avoiding the reliability problems of the components caused by temperature; at the same time, the components can reach the maximum designed service life; at the same time, the components can adapt to more severe working environments;

[0027] (3) The forced cooling hydraulic system of the scraper disclosed in the present invention uses the front axle and the rear axle as a hydraulic oil tank respectively, thereby reducing the number of hydraulic oil tank parts, avoiding the occupation of additional space, reducing the number of pipelines and parts, and increasing maintenance space;

[0028] (4) The forced cooling hydraulic system of the scraper disclosed in the present invention is respectively equipped with an oil suction filter and a high-pressure filter, so that the iron filings generated by the friction plate of the bridge brake can be completely filtered out, thereby ensuring the cleanliness of the hydraulic oil of the forced cooling hydraulic system and improving the reliability of the components in the bridge and the cooling system. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below.

[0030] Figure 1 The invention discloses a forced cooling hydraulic system for a scraper according to an embodiment of the present invention.

[0031] Reference numerals:

[0032] 1: Motor, 2: Dosing pump, 3: High-pressure filter, 3-1: Filter integrated in the high-pressure filter, 3-2: Bypass check valve integrated in the high-pressure filter, 3-3: Pressure alarm switch integrated in the high-pressure filter, 4: Axle oil radiator, 5: Axle oil temperature sensor, 6: Suction filter, 6-1: Filter integrated in the suction filter, 6-2: Bypass check valve integrated in the suction filter, 7: Connector block, 8: Rear axle, 8-1: Left side forced cooling assembly of rear axle, 8-2: Right side forced cooling assembly of rear axle, 8-3: Rear axle liquid level switch, 9: Front axle, 9-1: Left side forced cooling assembly of front axle, 9-2: Right side forced cooling assembly of front axle, 9-3: Front axle liquid level switch, 10: Controller, 11: Safety valve. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] Example 1

[0035] like Figure 1 As shown, the present invention discloses a forced cooling hydraulic system for a scraper, including a front axle cooling hydraulic system and a rear axle cooling hydraulic system, the two systems are independent and have similar structures.

[0036] The front axle cooling hydraulic system includes the front axle 9, the front axle left side forced cooling assembly 9-1, and the front axle right side forced cooling assembly 9-2. The front axle left side forced cooling assembly 9-1 and the front axle right side forced cooling assembly 9-2 are respectively located on the left and right sides of the front axle 9, and guide the cooled hydraulic oil to the key parts of the front axle 9 through a dedicated channel to take away the heat and maintain a suitable working temperature. The cooling assemblies on both sides are connected to the inlet of the oil suction filter 6 through the joint block 7, and the outlet of the oil suction filter 6 is connected to the inlet of the metering pump 2, and the outlet of the metering pump 2 is connected to the inlet of the high-pressure filter 3, and the outlet of the high-pressure filter 3 is connected to the bridge oil radiator 4 and the joint block 7 in turn.

[0037] The structure of the rear axle cooling hydraulic system is similar to that of the front axle 9, including the rear axle 8, the left side forced cooling assembly 8-1 of the rear axle, and the right side forced cooling assembly 8-2 of the rear axle. The left side forced cooling assembly 8-1 of the rear axle and the right side forced cooling assembly 8-2 of the rear axle are respectively located on the left and right sides of the rear axle 8, and guide the cooled hydraulic oil to the key parts of the rear axle 8 through a dedicated channel to take away the heat and maintain a suitable working temperature. The cooling assemblies on both sides are connected to the inlet of the oil suction filter 6 through the joint block 7, and the outlet of the oil suction filter 6 is connected to the inlet of the metering pump 2, and the outlet of the metering pump 2 is connected to the inlet of the high-pressure filter 3, and the outlet of the high-pressure pump filter 3 is connected to the bridge oil radiator 4 and the joint block 7.

[0038] It should be noted that since the front axle cooling hydraulic system and the rear axle cooling hydraulic system are independent, the number of components such as the connector block 7, the oil suction filter 6, the metering pump 2, the safety valve 11, the high-pressure filter 3, the axle oil radiator 4 and the axle oil temperature sensor 5 is at least 2, corresponding to the front and rear axle cooling hydraulic systems respectively.

[0039] The joint block 7 is a connecting hub between various components. The bottom of the left and right forced cooling assemblies of the front axle 9 is connected to the C3 and C2 interfaces of the joint block 7, and the top is connected to the B3 and B2 interfaces of the joint block 7. The hydraulic cylinders on the left and right sides of the front axle 9 are connected to the A3 and A2 interfaces of the joint block 7. The inlet of the metering pump 2 is connected to the C3 and C2 interfaces of the joint block 7, and the outlet of the bridge oil radiator is connected to the B3 and B2 interfaces of the joint block 7. The bottom of the left and right forced cooling assemblies of the rear axle 8 is connected to the C2 port of another joint block 7; the top is connected to the B3 and B2 interfaces of the joint block 7, the hydraulic cylinders on the left and right sides of the rear axle 8 are connected to the A3 and A2 interfaces of the joint block 7, the inlet of the metering pump 2 is connected to the C3 and C2 interfaces of the joint block 7, and the outlet of the bridge oil radiator is connected to the B3 and B2 interfaces of the joint block 7. The connection joint block 7 serves as a central distribution point to conveniently manage and control the interaction between multiple hydraulic lines. The C3 and C2 interfaces output the bridge oil in the forced cooling assembly, and the bridge oil after system filtration returns to the forced cooling assembly through the B3 and B2 interfaces.

[0040] The oil suction filter 6 filters the hydraulic oil again before it returns to the oil tank to ensure the oil quality. The oil suction filter 6 is provided with two sub-assemblies, including a filter 6-1 integrated in the oil suction filter and a bypass check valve 6-2 integrated in the oil suction filter. The filter is used for primary filtering, and the bypass check valve plays an emergency protection role. When the oil suction filter 6 is clogged, the bridge oil can be sucked out by the metering pump 2 through the bypass check valve.

[0041] The metering pump 2 is also equipped with a safety valve 11, which is arranged between the outlet of the oil suction filter 6 and the inlet of the high-pressure filter 3. If the subsequent pipeline and the one-way valve are blocked, the bridge oil can flow back to the oil suction port of the pump through the safety valve 11, preventing the metering pump 2 and other components from being damaged by excessive pressure.

[0042] The high-pressure filter 3 is used to achieve fine filtration of the hydraulic oil, remove tiny particles therein, and protect the downstream hydraulic components from wear. Three sub-components are integrated inside the high-pressure filter 3, including a filter 3-1 integrated in the high-pressure filter, a bypass one-way valve 3-2 integrated in the high-pressure filter, and a pressure alarm switch 3-3 integrated in the high-pressure filter. The filter is used to achieve secondary filtration, the bypass one-way valve plays an emergency protection role, and the pressure alarm switch is used to send an alarm signal. When the high-pressure filter 3 is also blocked, some of the bridge oil that has not been filtered for the second time is allowed to pass through the bypass one-way valve 3-2 to prevent the system pressure from being too high. At the same time, when the pressure difference generated reaches the set value of the pressure alarm switch, the whole vehicle alarms to remind the driver that the oil suction filter 6 and the filter element of the high-pressure filter 3 need to be replaced.

[0043] The inlet of the bridge oil radiator 4 is connected to the outlet of the high-pressure pump filter, and the outlet of the bridge oil radiator 4 is connected to the B3 and B2 interfaces of the joint block 7. The bridge oil then returns to the front / rear axle 8 forced cooling assembly through the joint block 7 to complete a closed loop. The front axle and rear axle forced cooling assemblies are regarded as a hydraulic oil tank and an open hydraulic system. The bridge oil radiator 4 uses water cooling or air cooling to effectively reduce the temperature of the hydraulic oil and prevent lubrication failure and mechanical damage caused by excessive oil temperature.

[0044] The forced cooling hydraulic system of the scraper in this embodiment cools the front and rear axles separately, which can effectively prevent the oil from flowing between the two. If too much oil in the front axle flows into the rear axle, or the oil in the rear axle flows into the front axle in reverse, it will cause an imbalance in the oil volume. This imbalance will not only affect the heat dissipation performance of each axle, but also reduce work efficiency, and insufficient oil may also affect the normal lubrication of the gears. Through the separate cooling design, the amount of oil inside each axle is ensured to remain stable, thereby optimizing the heat dissipation effect, ensuring gear lubrication, and improving overall operating efficiency.

[0045] Example 2

[0046] This embodiment adds electrical control on the basis of the first embodiment.

[0047] The forced cooling hydraulic system for the scraper in this embodiment also includes a controller 10, and electrical control is implemented based on the controller 10. Specifically, an axle oil temperature sensor 5 is provided at the outlet of the axle oil radiator 4, and the axle oil temperature sensor 5 is electrically connected to the controller 10. The quantitative pumps 2 in the cooling hydraulic systems of the front and rear axles 8 are driven by the motor 1. The motor 1 provides driving energy to drive the quantitative pump 2 to rotate and promote the flow of hydraulic oil in the entire system. The quantitative pump 2 delivers hydraulic oil according to a predetermined displacement to ensure sufficient pressure and flow in the system.

[0048] The controller 10 controls the speed of the motor 1 according to the bridge oil temperature after heat dissipation, forming a feedback closed-loop control to control the bridge oil within the optimal working range. Specifically, when the temperature sensor detects that the bridge oil temperature exceeds the set upper limit, the controller 10 controls to increase the speed of the motor 1, thereby improving the efficiency of the heat dissipation system and reducing the bridge oil temperature. On the contrary, if the temperature sensor detects that the bridge oil temperature is lower than the set lower limit, the controller 10 will reduce the speed of the motor 1, reduce the energy consumption of the heat dissipation system, and avoid overcooling.

[0049] In addition, the left and right side forced cooling assemblies of the front axle 9 and the left and right side forced cooling assemblies of the rear axle 8 are equipped with the front axle 9 liquid level switch 8-39-3 and the rear axle 8 liquid level switch 8-38-3 to monitor the oil level position. When leakage occurs in the pipelines and components, the oil level in the bridge becomes low, which is insufficient to control the transmission oil temperature in the bridge within the optimal range. An alarm is triggered and the entire vehicle is shut down, thereby protecting the axle and various components of the cooling hydraulic system.

[0050] Example 3

[0051] This embodiment discloses a method for operating a forced cooling hydraulic system of a scraper, comprising the following steps:

[0052] The metering pump 2 driven by the motor 1 sucks the bridge oil from the forced cooling assembly on the left and right sides of the front / rear bridge 8 through the oil suction filter 6 and the connector block 7. The oil suction filter 6 can filter out some impurities. A bypass check valve is configured in the oil suction filter 6. When the oil suction filter 6 is blocked, the bridge oil can be sucked out by the metering pump 2 through the bypass check valve. After the metering pump 2 sucks out the bridge oil, a safety valve 11 is configured to ensure the safety of the entire system. If the subsequent pipelines and check valves are blocked, the bridge oil can flow back to the pump's suction port through the safety valve 11 to prevent the metering pump 2 and other components from being damaged by excessive pressure.

[0053] The bridge oil then passes through the high-pressure filter 3 to filter the impurities not filtered out by the suction filter 6 for a second time. The high-pressure filter 3 is equipped with a filter, a bypass check valve, and a pressure alarm switch 3-3. When the high-pressure filter 3 is also blocked, the bridge oil can pass through the bypass check valve. If the pressure difference generated at the same time reaches the set value of the pressure alarm switch 3-3, the whole vehicle will alarm to remind the driver that the suction filter 6 and the filter element of the high-pressure filter 3 need to be replaced.

[0054] The filtered axle oil is cooled through the radiator, and the cooled axle oil is returned to the front / rear axle 8 forced cooling assembly through the joint block 7, completing a closed loop. The front axle 9 and the rear axle 8 forced cooling assembly are regarded as a hydraulic oil tank and an open hydraulic system.

[0055] Hydraulic switches are installed in the forced cooling assemblies on the left and right sides of the front / rear axle 8. When leakage occurs in the pipelines and components, the oil level in the axle becomes low, which is insufficient to control the transmission oil temperature in the axle within the optimal range. An alarm is triggered and the entire vehicle is shut down, thereby protecting the axle and various components of the cooling hydraulic system.

[0056] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A forced cooling hydraulic system for a scraper, characterized in that: The invention comprises a front axle and a rear axle, wherein the outlets of the front axle and rear axle forced cooling assemblies are respectively connected to an oil suction filter, a metering pump, a high-pressure filter and an axle oil radiator in sequence, and the outlets of the axle oil radiator are respectively connected to the inlets of the front axle and rear axle forced cooling assemblies, so that the axle oil in the front axle and rear axle forced cooling assemblies is filtered once by the oil suction filter, filtered twice by the high-pressure filter and cooled by the axle oil radiator, and then returns to the forced cooling assembly, forming a closed loop.

2. The forced cooling hydraulic system for scraper according to claim 1, characterized in that: A joint block is provided at the inlet and outlet of the front axle and rear axle forced cooling assembly as a connection hub. The bottom of the front axle and rear axle forced cooling assembly is connected to the C3 and C2 interfaces of the joint block, and the top is connected to the B3 and B2 interfaces of the joint block. The hydraulic cylinder in the bridge is connected to the A3 and A2 interfaces of the joint block, the inlet of the metering pump is connected to the C3 and C2 interfaces of the joint block, and the outlet of the bridge oil radiator is connected to the B3 and B2 interfaces of the joint block.

3. The forced cooling hydraulic system for scraper according to claim 2, characterized in that: A bypass check valve is arranged inside the oil suction filter, and two ends of the bypass check valve are connected to a joint block and a metering pump.

4. The forced cooling hydraulic system for scraper according to claim 3, characterized in that: The metering pump is equipped with a safety valve, which is arranged between the outlet of the oil suction filter and the inlet of the high-pressure filter.

5. The forced cooling hydraulic system for scraper according to claim 4, characterized in that: The high-pressure filter is internally provided with a bypass check valve and a pressure alarm switch. Both ends of the bypass check valve are connected between the outlet of the metering pump and the inlet of the bridge oil radiator. The pressure alarm switch collects bridge oil pressure difference information. When the pressure exceeds the threshold of the pressure alarm switch, the whole vehicle alarms.

6. The forced cooling hydraulic system for scraper according to claim 1, characterized in that: Hydraulic switches are configured in the front axle and rear axle forced cooling assemblies.

7. The forced cooling hydraulic system for a scraper according to any one of claims 1 to 6, characterized in that: The forced cooling hydraulic system also includes a controller and a bridge oil temperature sensor. The bridge oil temperature sensor is arranged at the outlet of the bridge oil radiator and is electrically connected to the controller. The metering pump is driven by a motor, and the motor is electrically connected to the controller. The controller controls the motor speed according to the bridge oil temperature after heat dissipation to form a feedback closed-loop control.

8. A method for operating a forced cooling hydraulic system of a scraper, characterized in that: According to the forced cooling hydraulic system for a scraper loader according to any one of claims 1 to 7, a motor drives a quantitative pump to suck axle oil out of the forced cooling assembly of the front axle and / or the rear axle, an oil suction filter filters a portion of impurities, and then the impurities not filtered out by the oil suction filter are secondary filtered through a high-pressure filter, and the filtered axle oil is dissipated through a radiator and then returned to the front and / or rear axle forced cooling assembly through a joint block.

9. The working method of the forced cooling hydraulic system of a scraper according to claim 8, characterized in that: The oil suction filter and / or the high-pressure filter is provided with a bypass valve inside. When the oil suction filter and / or the high-pressure filter is clogged, the bridge oil passes through the bypass one-way valve.

10. The working method of the forced cooling hydraulic system of a scraper according to claim 8, characterized in that: When the metering pump is equipped with a safety valve, when the downstream pipeline of the metering pump is blocked, the bridge oil flows back to the oil suction port of the pump through the safety valve.

Images