Tractor hydraulic system for preventing high oil temperature

Abstract

The utility model discloses a prevent tractor hydraulic system of high oil temperature, with the transmission oil of chassis sharing, including working pump, oil suction filter, oil return filter, chassis oil tank, multiway valve, work oil return channel and mid position oil return channel, the work oil return channel and mid position oil return channel are separated in the inside multiway valve, and the work oil return channel is connected chassis oil tank through the T oil port of multiway valve, and exchanges heat with the cold oil of chassis, and the mid position oil return channel is connected oil return filter through the HPCO oil port of multiway valve and directly enters the oil suction port of working pump after, and circulates and enters the hydraulic system. The utility model discloses working hydraulic system can realize the adjustment oil flow mode according to different working conditions, and forms open type circulation heat dissipation through T port and chassis loop when working, and forms closed circulation through HPCO port when in mid position standby, keeps oil clean and improves oil suction pressure, and protects hydraulic pump.

Description

Technical Field

[0001] This utility model relates to the field of engineering machinery technology, specifically a hydraulic system for tractors that prevents high oil temperature. 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 is not in operation, 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 is in operation, 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 tractor hydraulic system for preventing high oil temperature 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, and the outlet of the suction filter is connected to both the suction port of the working pump and the outlet of the return filter. The outlet of the working pump is connected to the P port of the multi-way valve. The multi-way valve contains a working return oil channel and a neutral return oil channel, which are disconnected from each other. The working return oil channel is connected to the chassis oil tank via the T port of the multi-way valve, and the neutral return oil channel is connected to the inlet of the return filter via the HPCO port of the multi-way valve.

[0009] Specifically, the oil suction filter and the oil return filter are integrated into a single unit.

[0010] 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.

[0011] 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.

[0012] Specifically, a radiator is also installed between the steering gear and the chassis oil tank.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] This design separates the working return oil channel and the neutral return oil channel within the multi-way valve. The working return oil channel connects directly to the chassis via the T-port of the multi-way valve, allowing the working return oil to flow back to the chassis and exchange heat with the cold oil in the chassis. The neutral return oil channel connects to the return oil filter via the HPCO port of the multi-way valve. After passing through the filter, the hydraulic oil directly enters the pump's suction port and circulates back into the hydraulic system. When the working hydraulic system is operating, the system return oil flows back to the chassis via the T-port of the multi-way valve, achieving heat exchange with the cold oil in the chassis and preventing high system oil temperature. When the working hydraulic system is not operating, the system return oil flows through the HPCO port of the multi-way valve into the return oil filter and then directly enters the pump's suction port, circulating back 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. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of a tractor hydraulic system in the prior art;

[0016] Figure 2This is a schematic diagram of a tractor hydraulic system for preventing high oil temperature according to the present invention.

[0017] In the diagram, 1-Working pump; 2-Suction filter; 3-Return filter; 4-Chassis oil tank; 5-Multi-way valve; 6-Working return oil channel; 7-Neutral return oil channel; 8-Chassis control valve; 9-Chassis pump; 10-Steering pump; 11-Steering gear; 12-Radiator. Detailed Implementation

[0018] 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.

[0019] like Figure 2 As shown, this embodiment discloses a tractor hydraulic system for preventing high oil temperature, 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 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.

[0020] 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.

[0021] 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.

[0022] The working hydraulic system consists of a working pump 1, a suction filter 2, a return filter 3, and a multi-way valve 5. The suction filter 2 and return filter 3 can be integrated into a single assembly. The inlet of the suction filter 2 is connected to the chassis oil tank 4, and its outlet is connected to the suction port of the working pump 1 and the outlet of the return filter 3, respectively. The cold oil in the chassis oil tank 4, after being filtered by the suction filter 2, merges with the return oil output from the return filter 3 and enters the working pump 1, achieving a dual-source suction structure. When the system has sufficient return oil, the hydraulic pump preferentially draws in the filtered return oil for recycling; when the system oil level is insufficient, due to the negative pressure difference formed at the inlet chamber of the suction filter 2, the oil in the chassis oil tank 4 is automatically replenished into the pump suction port under the static pressure of the oil surface, thus ensuring continuous and stable oil suction and achieving oil level self-balancing.

[0023] The key points of this embodiment are: the outlet of the working pump 1 is connected to the P port of the multi-way valve 5 to provide pressurized oil to the working hydraulic actuators. The multi-way valve 5 has two independent return oil channels: a working return oil channel 6 and a neutral return oil channel 7, which are structurally disconnected and independently arranged. The working return oil channel 6 is connected to the chassis oil tank 4 through the T port of the multi-way valve 5; the neutral return oil channel 7 is connected to the return oil filter 3 through the HPCO port of the multi-way valve 5. In this embodiment, the HPCO port is a high-pressure neutral straight channel, which allows the pump flow to be effectively delivered to subsequent components or valve groups in the system when the multi-way valve is in the neutral position, achieving series oil supply.

[0024] When the working hydraulic system is not operating, the valve core of multi-way valve 5 returns to the neutral position, the working return oil passage 6 is closed, and the neutral return oil passage 7 is open. The system return oil enters the return oil filter 3 through the HPCO port of multi-way valve 5, flows into the outlet chamber of suction filter 2 after filtration, and then enters the suction port of hydraulic pump, forming a closed loop in the working hydraulic system. In the closed loop state of the working hydraulic system, due to the long pipeline from chassis oil tank 4 to suction filter 2 and the high resistance, the hydraulic pump draws in return oil from return oil filter 3, reducing the flow rate drawn from chassis oil tank 4. This increases the suction pressure of the entire hydraulic system and reduces the amount of contaminated oil entering the system.

[0025] When the working hydraulic system is in operation, i.e., when the valve core of the multi-way valve 5 is in the actuated position, the pressure oil output from the working pump 1 enters the multi-way valve 5 through port P to supply oil to the working devices such as the lifting cylinder. At this time, the valve core switching opens the working return oil channel 6 and closes the neutral return oil channel 7. The return oil from the actuator flows directly back to the chassis oil tank 4 through port T, mixing with the cold oil in the chassis oil to form an open circulation, realizing heat exchange and oil cooling.

[0026] Therefore, this hydraulic system can automatically adjust the oil flow pattern according to different working conditions during actual use: when the operation is continuous, the system oil and the chassis cold oil are fully mixed, and the temperature rise is stable; when the system stops operating, the return oil circulates in a closed loop, maintaining a high level of oil cleanliness. The entire system performs excellently in terms of heat dissipation efficiency, cleanliness control, pump suction stability, and filter life, and is particularly suitable for high-power tractors and applications where multiple hydraulic subsystems operate in coordination. The entire system requires no additional switching control or solenoid valve action; it can automatically complete the flow direction switching based on the oil circuit structure itself, resulting in a simple structure and high reliability.

[0027] 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 tractor hydraulic system for preventing high oil temperature, comprising a working pump (1), a suction filter (2), a return filter (3), a chassis oil tank (4), and a multi-way valve (5), characterized in that: The oil inlet of the suction filter (2) is connected to the chassis oil tank (4), the oil outlet of the suction filter (2) is connected to the suction port of the working pump (1) and the oil outlet of the return oil filter (3) respectively, and the oil outlet of the working pump (1) is connected to the P port of the multi-way valve (5). The multi-way valve (5) is provided with a working return oil channel (6) and a neutral return oil channel (7), and the working return oil channel (6) and the neutral return oil channel (7) are disconnected. The working return oil channel (6) is connected to the chassis oil tank (4) through the T oil port of the multi-way valve (5), and the intermediate return oil channel (7) is connected to the oil inlet of the return oil filter (3) through the HPCO oil port of the multi-way valve (5).

2. The tractor hydraulic system for preventing high oil temperature according to claim 1, characterized in that, The oil suction filter (2) and the oil return filter (3) are integrated components.

3. A tractor hydraulic system for preventing high oil temperature 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).

4. A tractor hydraulic system for preventing high oil temperature 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).

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

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