High oil temperature prevention tractor hydraulic system

Abstract

The utility model discloses a kind of high oil temperature prevention tractor hydraulic systems, with chassis common transmission oil, including working pump, oil suction filter, oil return filter, chassis oil tank, multi-way valve, increase two-position three-way solenoid valve between oil return filter and oil suction filter, oil return filter is connected with the oil inlet of solenoid valve, two-position three-way solenoid valve first oil outlet intercommunication oil circuit between oil suction filter and working pump, second oil outlet is connected with chassis oil tank, working pump oil suction is provided with oil temperature sensor, when oil temperature sensor detects not reach set value, two-position three-way solenoid valve cannot be electrified, oil liquid flows back into working pump, closed cycle is formed, to ensure system oil liquid clean and improve oil suction pressure, protect hydraulic pump;When oil temperature sensor detects reach set value, two-position three-way solenoid valve is electrified, oil liquid flows back chassis, working pump is all from chassis oil suction, realize and chassis cold oil heat exchange and heat dissipation, prevent system oil temperature excessively high.

Description

Technical Field

[0001] This utility model relates to the field of engineering machinery technology, specifically a high oil temperature tractor hydraulic system. Background Technology

[0002] Existing tractor hydraulic systems such as Figure 1 As shown, the hydraulic system shares transmission oil with the chassis, using it as its own hydraulic oil. The hydraulic system generally includes a working hydraulic system, a steering hydraulic system, and a chassis shift lubrication system. Since the chassis transmission oil often has poor cleanliness, a suction filter 2 and a return filter 3 are installed. The working hydraulic system forms a closed-loop system, meaning that the return oil from the working hydraulic system, after passing through the return filter, directly enters the suction port of the working pump 1, instead of returning to the chassis. This allows the working hydraulic system oil to circulate internally, reducing the amount of dirty new oil drawn into the system from the chassis. This improves the cleanliness of the hydraulic system oil, extends the filter element's clogging cycle, increases suction pressure, and protects the hydraulic pump. Cooling of the chassis transmission oil is generally achieved by the return oil from the steering hydraulic system or chassis shift lubrication system first passing through a radiator and then returning to the chassis oil tank 4, thus cooling the entire chassis transmission oil.

[0003] The existing tractor hydraulic system has the following problems:

[0004] When the working hydraulic system operates continuously for a long time, the oil temperature of the closed working hydraulic system will rise. The high oil temperature cannot flow back to the chassis to neutralize and cool the chassis oil, which will cause the system to remain at a high temperature.

[0005] The information disclosed in the above background section is only intended to enhance the understanding of the overall background of this utility model, and should not be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art. Utility Model Content

[0006] To address the aforementioned deficiencies, the present invention aims to provide a tractor hydraulic system that prevents high oil temperature. When the working hydraulic system oil temperature is low, the working oil forms a closed-loop circulation, reducing the intake of relatively dirty new oil from the chassis into the system. This improves the cleanliness of the hydraulic system oil, extends the clogging cycle of the filter element, and increases the oil suction pressure, protecting the hydraulic pump. When the working hydraulic system oil temperature reaches a preset value, the system return oil flows back to the chassis, achieving heat exchange with the cold oil in the chassis and preventing high oil temperature in the system.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A high-oil-temperature-resistant tractor hydraulic system includes a working pump, a suction filter, a return filter, a chassis oil tank, and a multi-way valve. The inlet of the suction filter is connected to the chassis oil tank, the outlet of the suction filter is connected to the suction port of the working pump, the outlet of the working pump is connected to the P port of the multi-way valve, and the HPCO port of the multi-way valve is connected to the inlet of the return filter. A two-position three-way solenoid valve is installed between the return filter and the suction filter, and the outlet of the return filter is connected to the inlet of the two-position three-way solenoid valve. The two-position three-way solenoid valve is connected to the oil circuit between the oil suction filter and the working pump. The second oil outlet of the two-position three-way solenoid valve is connected to the chassis oil tank. An oil temperature sensor is installed at the oil suction port of the working pump. The oil temperature sensor is associated with the two-position three-way solenoid valve. When the oil temperature detected by the oil temperature sensor is less than a set value, the first oil outlet of the two-position three-way solenoid valve is opened and the second oil outlet is closed. When the oil temperature detected by the oil temperature sensor is greater than or equal to the set value, the first oil outlet of the two-position three-way solenoid valve is closed and the second oil outlet is opened.

[0009] Specifically, it also includes a chassis control valve and a chassis pump, wherein the oil suction port of the chassis pump is connected to the oil outlet of the oil suction filter, and the oil outlet of the chassis pump is connected to the chassis oil tank via the chassis control valve.

[0010] Specifically, it also includes a steering pump and a steering gear. The oil inlet of the steering pump is connected to the oil outlet of the oil suction filter, and the oil outlet of the steering pump is connected to the chassis oil tank via the steering gear.

[0011] Specifically, a radiator is also installed between the steering gear and the chassis oil tank.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] This solution adds a two-position three-way solenoid valve between the return oil filter and the suction oil filter. The return oil filter is connected to the inlet of the solenoid valve, and the first outlet of the solenoid valve is connected to the outlet of the suction oil filter, which in turn connects to the pump suction port. The second outlet of the solenoid valve is connected to the chassis. An oil temperature sensor is installed at the pump suction port. When the oil temperature detected by the sensor is below the set value, the electronic control system does not supply power to the solenoid valve, and the solenoid valve operates in the lower position. The oil from the return oil filter flows directly into the pump suction port through the solenoid valve and circulates into the hydraulic system. This reduces the amount of dirty new oil drawn into the system from the chassis, improving the cleanliness of the hydraulic system oil, extending the filter element's clogging cycle, increasing suction pressure, and protecting the hydraulic pump. When the oil temperature detected by the sensor reaches the set value, the electronic control system supplies power to the solenoid valve, and the solenoid valve operates in the upper position. The oil from the return oil filter flows back to the chassis through the solenoid valve, and the pump draws all the hydraulic oil from the chassis through the suction oil filter, achieving heat exchange with the cold oil in the chassis and preventing high system oil temperature. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of a tractor hydraulic system in the prior art;

[0015] Figure 2 This is a schematic diagram of a high oil temperature tractor hydraulic system according to the present invention.

[0016] In the diagram, 1-Working pump; 2-Suction filter; 3-Return filter; 4-Chassis oil tank; 5-Multi-way valve; 6-Two-position three-way solenoid valve; 8-Chassis control valve; 9-Chassis pump; 10-Steering pump; 11-Steering gear; 12-Radiator. Detailed Implementation

[0017] To explain the technical content, objectives, and effects of this utility model in detail, the following description is provided in conjunction with the embodiments and accompanying drawings. In the description of these embodiments, it should be understood that terms indicating orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings and are used only for the convenience of describing these embodiments and simplifying the description. They do not indicate or imply that the device or component 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 this utility model.

[0018] like Figure 2As shown, this embodiment discloses a high-oil-temperature-resistant tractor hydraulic system, mainly including a working pump 1, a suction filter 2, a return filter 3, a chassis oil tank 4, a multi-way valve 5, a chassis control valve 8, a chassis pump 9, a steering pump 10, a steering gear 11, and a radiator 12. This system shares the same chassis oil tank 4 with the chassis transmission oil; that is, the transmission oil in the chassis also serves as the working oil for the hydraulic system. In this embodiment, the vehicle's hydraulic system mainly consists of three parts: a working hydraulic system, a steering hydraulic system, and a chassis shifting lubrication system. These three systems share the chassis oil tank 4 as their oil source. The chassis oil first passes through the suction filter 2, and then through the pumps of their respective systems as the power transmission path.

[0019] The chassis shift lubrication system mainly consists of a chassis pump 9 and a chassis control valve 8. The oil suction port of the chassis pump 9 is connected to the oil outlet of the oil suction filter 2, and the oil outlet is connected to the chassis oil tank 4 via the chassis control valve 8, forming a circulation of transmission lubricating oil and shift control oil pressure.

[0020] The steering hydraulic system mainly consists of a steering pump 10 and a steering gear 11. The steering gear 11 is connected to the steering cylinder to drive steering. The oil suction port of the steering pump 10 is also connected to the oil outlet of the oil suction filter 2. The oil outlet of the steering pump 10 is connected to the chassis oil tank 4 via the steering gear 11, forming a circulation of the steering hydraulic system. A radiator 12 is also installed between the steering gear 11 and the chassis oil tank 4 for cooling the return oil.

[0021] The working hydraulic system consists of a working pump 1, a suction filter 2, a return filter 3, and a multi-way valve 5. This design separates the existing suction and return filter assembly into individual suction filter 2 and return filter 3. Specifically, the suction port of the working pump 1 is connected to the chassis oil tank 4 via the suction filter 2, and the outlet supplies oil to various actuators such as implement lifting cylinders and auxiliary hydraulic cylinders through the P port of the multi-way valve 5. The return oil from the actuators returns to the inlet of the return filter 3 via the HPCO port of the multi-way valve 5 for filtration. In this embodiment, the HPCO port is a high-pressure neutral position direct-flow port, allowing the remaining flow from the pump to be effectively delivered to subsequent components or valve groups in the system when the multi-way valve 5 is not in the neutral position, achieving series oil supply. The T port of the multi-way valve 5 is closed to form a closed system.

[0022] To address the issue of oil temperature rise during prolonged operation of existing closed-loop hydraulic systems, the key features of this embodiment are: a two-position three-way solenoid valve 6 is added between the return oil filter 3 and the suction oil filter 2, and an oil temperature sensor is installed at the suction port of the working pump 1. The inlet of the solenoid valve 6 is connected to the outlet of the return oil filter 3. The solenoid valve 6 has two outlets: the first outlet is connected to the oil circuit between the suction oil filter 2 and the working pump 1, and the second outlet is connected to the chassis oil tank 4. The oil temperature sensor and the solenoid valve 6 are connected via an electronic control system, which automatically switches the oil flow direction based on the detected oil temperature, thereby achieving automatic switching between closed-loop and open-loop circulation.

[0023] When the oil temperature detected by the oil temperature sensor is lower than the set temperature, the electronic control system does not supply power to the two-position three-way solenoid valve 6, and the two-position three-way solenoid valve 5 is in the lower working state. At this time, the first oil outlet is open and the second oil outlet is closed. The oil output from the return oil filter 3 flows directly back to the suction port of the working pump 1 through the two-position three-way solenoid valve 6, forming a closed oil circuit circulation. In this state, the hydraulic oil circulates in a closed loop within the system, reducing mixing with the chassis oil. This reduces the entry of external impurities, improves the cleanliness of the hydraulic oil, extends the service life of the suction filter 2 and the return oil filter 3, and also increases the suction pressure, protecting the hydraulic pump.

[0024] When the oil temperature detected by the oil temperature sensor reaches or exceeds the set temperature, the electronic control system supplies power to the two-position three-way solenoid valve 6. The solenoid valve switches to the upper working state, closing the first oil outlet and opening the second oil outlet. At this time, the oil output from the return oil filter 3 flows back to the chassis oil tank 4 through the solenoid valve 6, and the working pump 1 draws hydraulic oil back into the chassis oil tank 4 through the suction oil filter 2. In this working state, the return oil mixes with the cold oil in the chassis to achieve heat exchange, causing the oil temperature to drop, thereby preventing the system from experiencing performance degradation or component damage due to excessively high oil temperature under continuous high load.

[0025] The system's control process is entirely driven by the oil temperature signal, requiring no manual operation. It can quickly switch between closed-loop and open-loop operation based on the actual oil temperature, enabling the system to maintain high cleanliness at low temperatures and achieve effective cooling at high temperatures, ensuring stable and reliable operation of the hydraulic system under various working conditions.

[0026] Although the present invention has been described in detail above with specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A high-oil-temperature-resistant tractor hydraulic system, comprising a working pump (1), a suction filter (2), a return filter (3), a chassis oil tank (4), and a multi-way valve (5), wherein the inlet of the suction filter (2) is connected to the chassis oil tank (4), the outlet of the suction filter (2) is connected to the suction port of the working pump (1), the outlet of the working pump (1) is connected to the P port of the multi-way valve (5), and the HPCO port of the multi-way valve (5) is connected to the inlet of the return filter (3); characterized in that: A two-position three-way solenoid valve (6) is provided between the return oil filter (3) and the suction oil filter (2). The oil outlet of the return oil filter (3) is connected to the oil inlet of the two-position three-way solenoid valve (6). The first oil outlet of the two-position three-way solenoid valve (6) is connected to the oil circuit between the suction oil filter (2) and the working pump (1). The second oil outlet of the two-position three-way solenoid valve (6) is connected to the chassis oil tank (4). An oil temperature sensor is installed at the oil inlet of the working pump (1). The oil temperature sensor is associated with the two-position three-way solenoid valve (6). When the oil temperature detected by the oil temperature sensor is less than the set value, the first oil outlet of the two-position three-way solenoid valve (6) is opened and the second oil outlet is closed. When the oil temperature detected by the oil temperature sensor is greater than or equal to the set value, the first oil outlet of the two-position three-way solenoid valve (6) is closed and the second oil outlet is opened.

2. The high oil temperature resistant tractor hydraulic system according to claim 1, characterized in that, It also includes a chassis control valve (8) and a chassis pump (9), the oil inlet of the chassis pump (9) is connected to the oil outlet of the oil suction filter (2), and the oil outlet of the chassis pump (9) is connected to the chassis oil tank (4) via the chassis control valve (8).

3. The high oil temperature prevention tractor hydraulic system according to claim 1, characterized in that, It also includes a steering pump (10) and a steering gear (11). The oil inlet of the steering pump (10) is connected to the oil outlet of the oil filter (2), and the oil outlet of the steering pump (10) is connected to the chassis oil tank (4) via the steering gear (11).

4. A high-oil-temperature-resistant tractor hydraulic system according to claim 3, characterized in that, A radiator (12) is also provided between the steering gear (11) and the chassis oil tank (4).

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