Hydraulic station hydraulic system capable of providing two oil sources

Abstract

The utility model discloses a hydraulic station hydraulic system capable of providing two oil sources, which relates to the technical field of hydraulic systems and comprises a main oil way and an oil return way which are connected with an oil tank. A constant-pressure variable pump is mounted on the main oil way, and a proportional overflow valve is arranged on the constant-pressure variable pump; a connecting oil way connected with the main oil way is further arranged on the oil return oil way, and an overflow valve is installed on the connecting oil way. According to the utility model, two hydraulic oil sources can be provided, one is a constant displacement pump and an overflow valve, and the other is a constant-pressure variable displacement pump, so that whether the influence of the hydraulic oil sources on the pressure control effect of the designed electro-hydraulic proportional (servo) control system is different can be tested.

Description

Technical Field

[0001] The utility model relates to the technical field of hydraulic systems, and more specifically, to a hydraulic station hydraulic system capable of providing two oil sources. Background Technique

[0002] At present, the schemes for synchronous control of multiple oil cylinders can generally be divided into three categories: mechanical synchronization, hydraulic synchronization, and electro-hydraulic proportional (servo) synchronization. In occasions where high synchronous accuracy and requirements for the dynamic response process are required, the electro-hydraulic proportional (servo) synchronization method is often adopted. However, the control effect and stability of the electro-hydraulic proportional (servo) synchronization system are related to many factors, such as: the type of hydraulic oil source, the type of proportional valve (servo valve), different load conditions, hydraulic oil temperature, control algorithm, etc. Due to the existence of these factors, when designing an electro-hydraulic proportional (servo) synchronization system, there are often certain difficulties in the selection of some components, the control range of some parameters, and algorithm design.

[0003] At the same time, the current schemes for the pressure control system of oil cylinders can generally be divided into: pressure control by relief valve, pressure control by reducing valve, pressure control by reducing and relief valve, pressure control by proportional valve (servo valve), pressure control by switching valve, etc. And the control effect of pressure and the stability of the control system are related to many factors, such as: different hydraulic oil sources, different types of control valves, different load conditions, hydraulic oil temperature, control algorithm, etc. Due to the existence of these factors, when designing an electro-hydraulic pressure control system, there are often certain difficulties in the selection of some components, the control range of some parameters, and algorithm design.

[0004] However, there is currently no experimental bench for an electro-hydraulic proportional (servo) synchronization control system considering different hydraulic oil sources, nor is there a hydraulic station hydraulic system that can provide different hydraulic oil sources. Content of the Utility Model

[0005] The purpose of the utility model is to provide a hydraulic station hydraulic system capable of providing two oil sources, which can compare the control effects of different hydraulic oil sources during experiments.

[0006] To achieve the purpose of the utility model, the technical solution adopted is: a hydraulic station hydraulic system capable of providing two oil sources, including a main oil circuit and a return oil circuit connected to an oil tank; a constant pressure variable pump is installed on the main oil circuit, and a proportional relief valve is equipped on the constant pressure variable pump; a connecting oil circuit connected to the main oil circuit is also provided on the return oil circuit, and a relief valve is installed on the connecting oil circuit.

[0007] Furthermore, an oil suction filter, an oil suction stop valve, and a shock absorber are also installed at the inlet end of the constant pressure variable pump.

[0008] Furthermore, a high-pressure filter is also installed at the outlet end of the constant pressure variable pump.

[0009] Furthermore, an oil return filter, a cooler, and a solenoid valve are also installed on the oil return oil path.

[0010] Furthermore, an air filter, a liquid level gauge, a thermometer, and a heater are also installed on the fuel tank.

[0011] Furthermore, a pressure sensor and a pressure gauge are also installed on the main oil path.

[0012] Furthermore, a low-pressure stop valve is installed at the fuel tank drain port.

[0013] The beneficial effects of the present utility model are as follows:

[0014] 1. When the present utility model is used for experiments on a multi-cylinder synchronous control system and an oil cylinder pressure control system, the present utility model can provide two hydraulic oil sources, one of which is a "fixed displacement pump + relief valve", and the other is a "constant pressure variable pump", so as to test whether there are differences in the influence of the hydraulic oil source on the control effect of the designed electro-hydraulic proportional (servo) system.

[0015] 2. When the present utility model is used for experiments on a multi-cylinder synchronous control system and an oil cylinder pressure control system, the present utility model can test the influence of the hydraulic oil temperature on the synchronization and pressure control effects of the proportional (servo) control system. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings illustrate exemplary embodiments of the present utility model and, together with the description thereof, are used to explain the principles of the present utility model. These drawings are included to provide a further understanding of the present utility model, and the drawings are included in this specification and form a part of this specification.

[0017] Figure 1 It is a hydraulic schematic diagram of a hydraulic station hydraulic system that can provide two oil sources.

[0018] Markings in the drawings and corresponding component names:

[0019] 1. Air filter, 2. Liquid level gauge, 3. Suction filter, 4. Suction stop valve, 5. Shock absorber hose, 6. Thermometer, 7. Heater, 8. Low-pressure stop valve, 9. Oil return filter, 10. Cooler, 11. Constant pressure variable pump, 12. High-pressure filter, 13. Proportional relief valve, 14. Solenoid valve, 15. Relief valve, 16. Main oil path, 17. Oil return oil path, 18. Pressure gauge, 19. Pressure sensor, 20. Fuel tank, 21. Connecting oil path. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] The present utility model will be further described in detail below in conjunction with the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the relevant content and do not limit the present utility model. Additionally, it should be noted that for ease of description, only the parts related to the present utility model are shown in the drawings.

[0021] It should be noted that, without conflict, the embodiments in the present utility model and the features in the embodiments can be combined with each other. The present utility model will be described in detail below with reference to the drawings and embodiments.

[0022] As Figure 1 shown, a hydraulic system of a hydraulic station capable of providing two oil sources provided by the present utility model includes an oil tank 20. A low-pressure stop valve 8 is installed at the oil discharge port of the oil tank 20, and a main oil circuit 16 and a return oil circuit 17 are also connected to the oil tank 20. The main oil circuit 16 provides hydraulic oil for the actuating element, and the return oil circuit 17 is used to return the hydraulic oil to the oil tank 20. A constant-pressure variable pump 11 is also installed on the main oil circuit 16. The constant-pressure variable pump 11 pumps and delivers the hydraulic oil in the oil tank 20 to provide hydraulic oil for the hydraulic system. At the same time, a proportional relief valve 13 is also provided on the constant-pressure variable pump 11, and the overflow oil port of the proportional relief valve 13 is connected to the oil tank 20. A connecting oil circuit 21 is also connected between the return oil circuit 17 and the main oil circuit 16, and a relief valve 15 is installed on the connecting oil circuit 21.

[0023] As a further option of this embodiment, an oil suction filter 3, an oil suction stop valve 4, and a shock absorber hose 5 are also installed at the inlet end of the constant-pressure variable pump 11. Specifically, the oil suction filter 3 is installed at the inlet end of the oil suction stop valve 4, the shock absorber hose 5 is installed at the inlet end of the constant-pressure variable pump 11, the oil suction stop valve 4 is installed between the oil suction filter 3 and the shock absorber hose 5, and the oil suction filter 3 is used to filter the hydraulic oil entering the main oil circuit 16. The shock absorber hose 5 can prevent the vibration generated during the operation of the constant-pressure variable pump 11 from being transmitted to the oil tank 20, and the oil suction stop valve 4 controls the truncation and connection between the oil suction port of the constant-pressure variable pump 11 and the oil tank 20. A high-pressure filter 12 is also installed at the outlet end of the constant-pressure variable pump 11. The high-pressure filter 12 performs secondary filtration on the hydraulic oil delivered by the constant-pressure variable pump 11 to prevent the operation of subsequent actuating elements from being affected due to impurities in the hydraulic oil delivered by the constant-pressure variable pump 11.

[0024] As a further option of this embodiment, an oil return filter 9, a cooler 10, and a solenoid valve 14 are also installed on the return oil circuit 17. The oil return filter 9 filters the hydraulic oil flowing back to the oil tank 20, the cooler 10 is used to cool the hydraulic oil flowing back to the oil tank 20, and the solenoid valve 14 is used to control the unloading and loading of the constant-pressure variable pump 11.

[0025] As a further option in this embodiment, an air filter 1, a liquid level gauge 2, a thermometer 6, and a heater 7 are also installed on the fuel tank 20. The liquid level gauge 2 is used to detect the liquid level height of the hydraulic oil in the fuel tank 20, the thermometer 6 is used to detect the temperature of the hydraulic oil in the fuel tank 20, and the heater 7 is used to heat the hydraulic oil in the fuel tank 20.

[0026] As a further option in this embodiment, in order to facilitate monitoring the hydraulic oil pressure of the main oil circuit 16, a pressure gauge 18 and a pressure sensor 19 are installed on the main oil circuit 16.

[0027] As a further option in this embodiment, in order to facilitate controlling the opening and closing of the fuel filling port of the fuel tank 20, a low-pressure cut-off valve 8 is also installed at the oil drain port of the fuel tank 20.

[0028] When this hydraulic station hydraulic system is used for the related functions of a multi-cylinder synchronous control system:

[0029] 1. Realization of two hydraulic oil sources: The two hydraulic oil sources are respectively a "fixed displacement pump + relief valve" hydraulic oil source and a "constant pressure variable pump" hydraulic oil source.

[0030] Set the set pressure of the relief valve 15 slightly higher than the system rated pressure; fix the adjustment value of the proportional relief valve 13 at a relatively high value so that the constant pressure setting value of the constant pressure variable pump 11 is slightly higher than the set pressure of the relief valve 15. In this way, the displacement of the constant pressure variable pump 11 is always at the maximum displacement, and the hydraulic oil source at this time is the "fixed displacement pump + relief valve" hydraulic oil source.

[0031] Set the set pressure of the relief valve 15 slightly higher than the system rated pressure; set the adjustment value of the proportional relief valve 13 to a value within a certain range so that the constant pressure setting value of the constant pressure variable pump 11 takes different setting values according to experimental needs, but the maximum setting value does not exceed the rated pressure of the system. In this way, the actual system pressure reaches the constant pressure setting value of the constant pressure variable pump 11, and the displacement of the constant pressure variable pump 11 is at a relatively small displacement to maintain the system pressure at the constant pressure setting value of the constant pressure variable pump 11. The hydraulic oil source at this time is the "constant pressure variable pump" hydraulic oil source.

[0032] When this hydraulic station hydraulic system is used for the related functions of a cylinder pressure control system:

[0033] 1. Realization of two hydraulic oil sources: The two hydraulic oil sources are respectively a "fixed displacement pump + relief valve" hydraulic oil source and a "constant pressure variable pump" hydraulic oil source.

[0034] Set the set pressure of the overflow valve 15 to be slightly higher than the system rated pressure; fix the setting value of the proportional overflow valve 13 at a relatively high value so that the constant pressure setting value of the constant pressure variable pump 11 is slightly higher than the set pressure of the overflow valve 15. In this way, the displacement of the constant pressure variable pump 11 is always at the maximum displacement, and the hydraulic oil source at this time is the "constant displacement pump + overflow valve" hydraulic oil source.

[0035] Set the set pressure of the overflow valve 15 to be slightly higher than the system rated pressure; set the setting value of the proportional overflow valve 13 to a value within a certain range so that the constant pressure setting value of the constant pressure variable pump 11 takes different setting values according to experimental needs, but the maximum setting value does not exceed the rated pressure of the system. In this way, the actual system pressure reaches the constant pressure setting value of the constant pressure variable pump 11, and the displacement of the constant pressure variable pump 11 is in a relatively small displacement to maintain the system pressure at the constant pressure setting value of the constant pressure variable pump 11. The hydraulic oil source at this time is the "constant pressure variable pump" hydraulic oil source.

[0036] In the description of this specification, the descriptions with reference to terms such as "one embodiment / way", "some embodiments / ways", "example", "specific example" or "some examples" etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment / way or example are included in at least one embodiment / way or example of this application. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment / way or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments / ways or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments / ways or examples described in this specification and the features of different embodiments / ways or examples.

[0037] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" can explicitly or implicitly include at least one of such features. In the description of this application, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0038] Those skilled in the art should understand that the above embodiments are only for clearly explaining the present invention and not for limiting the scope of the present invention. For those skilled in the art, other changes or modifications can be made based on the above disclosure, and these changes or modifications are still within the scope of the present invention.

Claims

1. A hydraulic system for a hydraulic station that can provide two oil sources, characterized in that: The invention comprises a main oil circuit (16) and an oil return circuit (17) connected to an oil tank (20); a constant pressure variable pump (11) is installed on the main oil circuit (16), and a proportional relief valve (13) is provided on the constant pressure variable pump (11); a connecting oil circuit (21) connected to the main oil circuit (16) is also provided on the oil return circuit (17), and a relief valve (15) is installed on the connecting oil circuit (21).

2. The hydraulic system of the hydraulic station capable of providing two oil sources according to claim 1, characterized in that: The inlet end of the constant pressure variable pump (11) is also equipped with an oil suction filter (3), an oil suction valve (4), and a shock absorbing throat (5).

3. The hydraulic system of the hydraulic station capable of providing two oil sources according to claim 1, characterized in that: A high-pressure filter (12) is also installed at the outlet end of the constant-pressure variable pump (11).

4. The hydraulic system of the hydraulic station capable of providing two oil sources according to claim 1, 2 or 3, characterized in that: The oil return line (17) is also equipped with an oil return filter (9), a cooler (10), and a solenoid valve (14).

5. The hydraulic system of the hydraulic station capable of providing two oil sources according to claim 1, 2 or 3, characterized in that: The oil tank (20) is also equipped with an air filter (1), a liquid level meter (2), a thermometer (6), and a heater (7).

6. The hydraulic system of the hydraulic station capable of providing two oil sources according to claim 4, characterized in that: A pressure sensor (19) and a pressure gauge (18) are also installed on the main oil circuit (16).

7. The hydraulic system of the hydraulic station capable of providing two oil sources according to claim 4, characterized in that: The oil drain port of the oil tank (20) is equipped with a low-pressure stop valve (8).

Images