Hydraulic oil circuit of tractor

Abstract

The utility model provides a tractor hydraulic oil circuit. Comprising an oil tank, a lifting oil way and a steering oil way. A first oil pump and a hydraulic valve assembly are sequentially arranged in the lifting oil way, and the hydraulic valve assembly is connected with a lifting oil cylinder and a hydraulic output connector. A second oil pump, a steering gear assembly and a second radiator are sequentially arranged in the steering oil way, and the steering gear assembly is connected with a steering oil cylinder. The lifting oil way and the steering oil way are arranged in parallel, and the inlet end and the outlet end of the lifting oil way are connected with the oil tank. The lifting oil way and the steering oil way share the same oil tank, and the second radiator is additionally arranged on the oil return way of the steering oil way, so that the purpose of radiating the lifting oil way is achieved.

Description

Technical Field

[0001] The utility model relates to an agricultural machinery control system, in particular to a tractor hydraulic oil circuit. Background Art

[0002] As the horsepower of the tractor increases, the flow rate of the hydraulic system increases synchronously. At the same time, in order to ensure the cleanliness of the hydraulic system, the lifting oil circuit uses an independent hydraulic oil tank. During the use of the tractor, as the oil filter element is blocked, the hydraulic components such as the pump cylinder valve are worn and the internal leakage increases, the balance temperature of the hydraulic lifting oil circuit gradually increases, resulting in a decrease in oil viscosity, a decrease in lubrication ability, and aging or damage of the seals, which causes hydraulic component leakage, failure and other faults.

[0003] To solve the heating problem of the hydraulic lifting oil circuit of the tractor, the current solution is to install an oil radiator in the hydraulic lifting oil circuit to reduce the oil temperature. However, the flow rate of the hydraulic lifting oil circuit increases with the horsepower upgrade. In order to ensure that the oil return back pressure of the lifting oil circuit is not too large, the diameter and volume of the oil radiator also need to be increased accordingly. However, the positional relationship between the various parts in the hydraulic lifting oil circuit area is relatively fixed, and it is difficult to arrange a larger oil radiator. Utility Model Content

[0004] The utility model aims to provide a tractor hydraulic oil circuit to overcome the above-mentioned defects.

[0005] The utility model provides a tractor hydraulic oil circuit, comprising:

[0006] tank;

[0007] A lifting oil circuit, in which a first oil pump and a hydraulic valve assembly are sequentially arranged, and the hydraulic valve assembly is connected to a lifting oil cylinder and a hydraulic output joint;

[0008] A steering oil circuit, in which a second oil pump, a steering gear assembly and a second radiator are sequentially arranged, and the steering gear assembly is connected to a steering oil cylinder;

[0009] The lifting oil circuit and the steering oil circuit are arranged in parallel, and the inlet and outlet ends thereof are both connected to the oil tank.

[0010] Preferably, an oil suction filter is provided on the lifting oil circuit and / or the steering oil circuit.

[0011] Preferably, a high-pressure oil filter is provided between the first oil pump and the hydraulic valve assembly.

[0012] Preferably, the hydraulic valve assembly comprises: a plurality of hydraulic output valves and hydraulic lifting valves connected in series, and a first safety valve connected to the hydraulic output valve and the hydraulic lifting valve;

[0013] The hydraulic output valve is connected to the hydraulic output joint; the hydraulic lifting valve is connected to the lifting cylinder.

[0014] Preferably, the steering gear assembly includes a steering gear, a hydraulic steering valve connected to the steering oil circuit and controlled by the steering gear; the hydraulic steering valve is connected to the steering cylinder.

[0015] Preferably, a clutch power-assisting valve assembly is connected in series between the steering gear assembly and the second radiator, and the clutch power-assisting valve assembly is connected to a clutch power-assisting oil cylinder.

[0016] Preferably, the pressure medium flow rate of the steering oil circuit is smaller than the pressure medium flow rate of the lifting oil circuit.

[0017] Preferably, it also includes: a lubricating oil circuit, whose inlet and outlet ends are connected to the chassis transmission housing, the lubricating oil circuit is connected in series with a third oil pump, a third radiator and a chassis lubrication internal oil channel, and a third safety valve is also connected in parallel between the third radiator and the third oil pump.

[0018] Preferably, the third oil pump and the second oil pump are double pumps.

[0019] Preferably, a first radiator is also provided on the lifting oil circuit.

[0020] Compared with the prior art, the tractor hydraulic oil circuit provided by the utility model has the following beneficial effects: the utility model achieves the purpose of heat dissipation for the lifting oil circuit by allowing the lifting oil circuit and the steering oil circuit to share the same oil tank and adding a second radiator to the return oil circuit of the steering oil circuit; and because the flow rate of the steering oil circuit system is small, the size of the second radiator can be guaranteed, and there is no need to significantly change the layout of the existing equipment or make complex adjustments to other related components, which is convenient for retrofitting and designing existing tractors. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The utility model is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0022] Figure 1 It is a structural schematic diagram of an embodiment of the hydraulic oil circuit in the utility model.

[0023] Figure 2 It is a structural schematic diagram of another embodiment of the hydraulic oil circuit in the utility model.

[0024] 1. Oil tank; 2. Lifting oil circuit; 21. Oil suction filter; 22. First oil pump; 23. High-pressure oil filter; 24. Bypass valve; 25. Hydraulic valve assembly; 251. Hydraulic output valve; 252. Hydraulic lifting valve; 253. First safety valve; 26. Lifting assembly; 261. Lifting cylinder; 262. One-way throttle valve; 27. Hydraulic output joint; 28. First radiator; 3. Steering oil circuit; 31. Second oil pump; 32. Steering gear assembly; 321. Steering gear; 322. Hydraulic steering valve; 33. Steering cylinder; 34. Clutch power-assist valve assembly; 35. Clutch power-assist cylinder; 36. Second radiator; 37. Second safety valve; 4. Lubricating oil circuit; 41. Transmission chassis housing; 42. Third oil pump; 43. Third radiator; 44. Chassis lubrication internal oil channel; 45. Third safety valve. DETAILED DESCRIPTION

[0025] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] In order to simplify the drawings, only the parts related to the utility model are schematically shown in each figure, and they do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically drawn or marked. In this article, "one" not only means "only one", but also means "more than one".

[0027] It should be further understood that the term “and / or” used in the specification and appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0028] In this article, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0029] In addition, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0030] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the specific implementation methods of the utility model will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0031] See also Figures 1 to 2 This embodiment provides a tractor hydraulic oil circuit, including: an oil tank 1, a lifting oil circuit 2, a steering oil circuit 3 and a lubricating oil circuit 4.

[0032] The lifting oil circuit 2 is provided with a first oil pump 22 and a hydraulic valve assembly 25 in sequence, and the hydraulic valve assembly 25 is connected to a lifting oil cylinder 261 and a hydraulic output joint 27; the steering oil circuit 3 is provided with a second oil pump 31, a steering gear assembly 32 and a second radiator 36 in sequence, and the steering gear assembly 32 is connected to a steering oil cylinder 33; the lifting oil circuit 2 and the steering oil circuit 3 are provided in parallel, and their inlet and outlet ends are both connected to the oil tank 1. Among them, the lifting oil circuit 2 and the steering oil circuit 3 share the same oil tank 1, and the second radiator 36 is added to the steering oil circuit 3 to dissipate heat for the lifting oil circuit 2; and because the system flow of the steering oil circuit 3 is small, the size of the second radiator 36 can be guaranteed, and there is no need to significantly change the layout of the existing equipment or make complex adjustments to other related components, which is convenient for retrofitting and designing existing tractors.

[0033] The hydraulic valve assembly 25 and the steering gear assembly 32 have multiple possible structures. This embodiment provides an exemplary structure of the hydraulic valve assembly 25 and the steering gear assembly 32. The hydraulic valve assembly 25 includes: three groups of hydraulic output valves 251 and hydraulic lifting valves 252 connected in series, and a first safety valve 253 connected to the hydraulic output valves 251 and the hydraulic lifting valves 252; the hydraulic output valve 251 is connected to the hydraulic output joint 27, and the hydraulic lifting valve 252 is connected to the lifting assembly 26. The steering gear assembly 32 includes a steering gear 321, a hydraulic steering valve 322 connected to the steering oil circuit 3 and controlled by the steering gear 321; the hydraulic steering valve 322 is connected to the steering oil cylinder 33.

[0034] The inlet and outlet ends of the lubricating oil circuit 4 are connected to the chassis transmission housing. The third oil pump 42, the third radiator 43 and the chassis lubricating internal oil channel 44 are connected in series in sequence on the lubricating oil circuit 4. A third safety valve 45 is also connected in parallel between the third radiator 43 and the third oil pump 42. The chassis transmission parts are lubricated through the lubricating oil circuit 4, and the lubricating oil is dissipated through the third radiator 43. The third safety valve 45 is connected in parallel between the third radiator 43 and the third oil pump 42. The opening pressure of the third safety valve 45 is lower than the maximum withstand pressure of the oil radiator. The safety valve unloads oil and directly returns the oil to the transmission chassis housing 41, which is used to protect the third radiator 43 from being damaged by the return oil impact.

[0035] In a further embodiment, the third oil pump 42 and the second oil pump 31 are double pumps, specifically double gear pumps, and the second oil pump 31 and the third oil pump 42 are used as a double pump and can work simultaneously, and the front pump and the rear pump of the double gear pump respectively supply oil to the lifting oil circuit 2 and the steering oil circuit 3. The first oil pump 22 is a constant flow pump, which can better cope with system pressure fluctuations and ensure the smoothness and accuracy of the operation of the steering oil circuit 3.

[0036] In a further embodiment, an oil suction filter 21 is provided on the lifting oil circuit 2 and / or the steering oil circuit 3 and / or the lubricating oil circuit 4, which is used to filter the oil in the oil tank 1, protect the double gear pump and / or the constant flow pump, and prevent impurities from entering. The lifting oil circuit 2 and the steering oil circuit 3 are connected to the same oil tank 1, and the lifting oil circuit 2 and the steering oil circuit 3 can share the same oil suction filter 21. Of course, the lifting oil circuit 2 and the steering oil circuit 3 can also use two oil suction filters 21 independently.

[0037] In a further embodiment, the oil inlet section of the lifting oil circuit 2 is provided with a high-pressure oil filter 23, and the high-pressure oil filter 23 is also connected in parallel with a bypass valve 24. The oil in the oil tank 1 is filtered by the high-pressure oil filter 23 to protect the hydraulic valve of the lifting oil circuit 2 and prevent impurities from entering the hydraulic valve assembly 25 of the lifting oil circuit 2.

[0038] In a further embodiment, a clutch boost valve assembly 34 is further provided in the steering oil circuit 3, and the clutch boost valve assembly 34 is connected to a clutch boost cylinder 35. By integrating the clutch boost function in the steering oil circuit 3 and adding a clutch boost hydraulic valve to supply oil to the boost cylinder, the operating force when stepping on the clutch pedal is reduced, thereby improving driving comfort.

[0039] In a further embodiment, a second safety valve 37 (1.5 MPa) is connected in parallel between the clutch boost valve assembly 34 and the second radiator 36, and the opening pressure of the second safety valve 37 is lower than the maximum withstand pressure of the second radiator 36. When there is a hydraulic medium impact, the safety valve unloads oil and directly returns to the oil tank 1 to prevent the second radiator 36 from being damaged by the impact.

[0040] In a further embodiment, the lifting assembly 26 includes two lifting cylinders 261, and the lifting cylinders 261 are connected to the hydraulic valve assembly 25 through a one-way throttle valve 262. The lifting cylinders 261 act on the lifter to drive the machine to rise and fall; the one-way throttle valve 262 reduces the descending speed of the lifting cylinders 261 to ensure the smooth descent of the lifter and the machine.

[0041] In a further embodiment, a first radiator 28 is further provided on the lifting oil circuit 2. The first radiator 28 is the original radiator of the lifting oil circuit 2. The cooperation of the first radiator 28 and the second radiator 36 forms a double-layer heat dissipation mechanism to improve the heat dissipation capacity of the lifting oil circuit 2.

[0042] In order to facilitate those skilled in the art to understand the technical solution of the present application, a brief description of its working principle is now given: after the tractor is running, the oil in the oil tank 1 will be filtered through the oil suction filter 21 and enter the double gear pump, and the front pump of the double gear pump supplies oil to the lifting oil circuit 2. The oil enters the hydraulic valve assembly 25 after being filtered through the lifting oil pressure filter. If the handle of the lifting hydraulic valve assembly 25 is not operated, the oil directly returns to the hydraulic oil tank 1 through the lifting hydraulic valve return port T. If the handle is operated, the oil passes through the one-way throttle valve 262 and enters the left lifting cylinder 261 and the right lifting cylinder 261 respectively, and the cylinder piston moves. At the same time, other handles can also be operated, and the oil enters the hydraulic components on the tractor's implements through the hydraulic output quick-change joint to control the movement of the implements.

[0043] At the same time, the oil in the oil tank 1 will be filtered by the oil suction filter 21, enter the constant flow pump, and then enter the steering gear assembly 32. If the steering wheel is operated, the oil in the steering gear 321 will enter the steering cylinder 33, and the rest of the oil will enter the clutch booster valve. If the steering wheel is not operated, the oil will directly enter the clutch booster valve after passing through the steering gear 321, or the clutch pedal will be stepped on at this time, causing the clutch booster cylinder 35 to open, and the oil will enter the clutch booster cylinder 35 to push the clutch booster cylinder 35 to move. All subsequent oil will return to the independent hydraulic oil tank 1 after passing through the second radiator 36 for heat dissipation.

[0044] At the same time, the oil in the transmission chassis housing 41 will be filtered by the oil suction filter 21 and enter the double gear pump, and the double gear pump rear pump supplies oil to the chassis lubrication system. Then, after the oil is cooled by the third radiator 43, it enters the chassis lubrication internal oil channel 44 to lubricate the chassis transmission parts.

[0045] It will be apparent to those skilled in the art that various modifications and variations can be made to the above exemplary embodiments of the present invention without departing from the spirit and scope of the present invention. Therefore, it is intended that the present invention covers modifications and variations of the present invention that fall within the scope of the appended claims and their equivalent technical solutions.

Claims

1. A tractor hydraulic oil circuit, characterized in that: include: tank; A lifting oil circuit, in which a first oil pump and a hydraulic valve assembly are sequentially arranged, and the hydraulic valve assembly is connected to a lifting oil cylinder and a hydraulic output joint; A steering oil circuit, in which a second oil pump, a steering gear assembly and a second radiator are sequentially arranged, and the steering gear assembly is connected to a steering oil cylinder; The lifting oil circuit and the steering oil circuit are arranged in parallel, and the inlet and outlet ends thereof are both connected to the oil tank.

2. The tractor hydraulic oil circuit according to claim 1, characterized in that: An oil suction filter is provided on the lifting oil circuit and / or the steering oil circuit.

3. The tractor hydraulic oil circuit according to claim 1, characterized in that: A high-pressure oil filter is arranged between the first oil pump and the hydraulic valve assembly.

4. The tractor hydraulic oil circuit according to claim 1, characterized in that: The hydraulic valve assembly comprises: a plurality of hydraulic output valves and hydraulic lifting valves connected in series, and a first safety valve connected to the hydraulic output valve and the hydraulic lifting valve; The hydraulic output valve is connected to the hydraulic output joint; the hydraulic lifting valve is connected to the lifting assembly.

5. The tractor hydraulic oil circuit according to claim 1, characterized in that: The steering gear assembly includes a steering gear, and a hydraulic steering valve connected to the steering oil circuit and controlled by the steering gear; the hydraulic steering valve is connected to the steering cylinder.

6. The tractor hydraulic oil circuit according to claim 1, characterized in that: A clutch power-assisting valve assembly is also connected in series between the steering gear assembly and the second radiator, and the clutch power-assisting valve assembly is connected to a clutch power-assisting oil cylinder.

7. The tractor hydraulic oil circuit according to claim 1, characterized in that: The pressure medium flow rate of the steering oil circuit is smaller than the pressure medium flow rate of the lifting oil circuit.

8. The tractor hydraulic oil circuit according to claim 1, characterized in that: Also includes: The lubricating oil circuit has its inlet and outlet connected to the chassis transmission housing. The lubricating oil circuit is connected in series with a third oil pump, a third radiator and a chassis lubrication internal oil channel in sequence. A third safety valve is also connected in parallel between the third radiator and the third oil pump.

9. The tractor hydraulic oil circuit according to claim 8, characterized in that: The third oil pump and the second oil pump are double pumps.

10. The tractor hydraulic oil circuit according to any one of claims 1 to 9, characterized in that: The lifting oil circuit is also provided with a first radiator.

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