Hydraulic power station with unloading loop and operation method

Abstract

The invention belongs to the technical field of hydraulic transmission systems, and particularly relates to a hydraulic power station with an unloading loop and an operation method.The hydraulic power station comprises an oil tank and a hydraulic pump, the hydraulic pump is connected with a three-position four-way reversing valve in series through an oil way relative to the oil tank, and an external port of the three-position four-way reversing valve is connected with a shuttle valve through an oil way; the side end of the shuttle valve is connected with a two-position two-way hydraulic control valve, and the two-position two-way hydraulic control valve is connected to an oil way where the hydraulic pump is connected with an internal connection port of the three-position four-way reversing valve in parallel relative to the oil tank. Compared with an existing electric control unloading mode, the hydraulic control unloading device has the advantages that the structure is simple, the later maintenance cost is lower, the maintenance difficulty is lower, the operation process is simpler and more visual, and the overflow valve does not need to be frequently and manually adjusted, so that the unloading stability and reliability are greatly improved, and the development requirement of a hydraulic power station can be better met.

Description

Technical Field

[0001] The invention belongs to the technical field of hydraulic transmission systems, and in particular relates to a hydraulic power station with an unloading circuit and an operating method. Background Art

[0002] As the core component of the hydraulic transmission system, the hydraulic power station is widely used in various industrial fields, including oil fields, mobile platforms (such as vehicles, robots, etc.) and other occasions that require hydraulic transmission. Its performance and efficiency directly affect the operation effect of the entire hydraulic transmission system. At present, when the hydraulic power station is started, most of them manually adjust the overflow valve to control the pressure of the hydraulic transmission system. Especially in complex working conditions such as oil fields, when the reversing valve is in the closed position or the outlet is a one-way valve with load, the hydraulic transmission system is very likely to frequently adjust the overflow valve due to the needs of the load to adapt to the needs of different work. This frequent manual adjustment method not only increases the difficulty of operation and working time, but also easily leads to overflow loss and heating problems, reducing the overall efficiency of the hydraulic transmission system. At the same time, it is also very easy to cause safety problems due to misoperation of the staff.

[0003] The existing technology has research on hydraulic power stations with unloading systems to achieve flow regulation output, such as patent application CN210240193U-Hydraulic power station for mobile platforms, which achieves output flow regulation by adding proportional relief valves, unloading valves, safety valves, etc., solving the problem of difficult operation and low efficiency of the current frequent manual adjustment method. However, the existing hydraulic power station completes unloading by electronic control, but it is difficult to effectively control the stability and reliability of unloading, making unloading more complicated in actual operation and more difficult to maintain in the later stage, which is difficult to meet the development requirements of hydraulic power stations. Therefore, a new technical solution is needed to solve the above technical problems. Summary of the invention

[0004] The purpose of the present invention is to provide a hydraulic power station with a unloading circuit and an operating method, so as to solve the problems raised in the above background technology that it is difficult for the hydraulic power station at the current stage to effectively control the stability and reliability of unloading, which makes the unloading more complicated in the actual operation process and the subsequent maintenance more difficult, and it is difficult to meet the development requirements of the hydraulic power station.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a hydraulic power station with an unloading circuit, comprising an oil tank and a hydraulic pump connected to the oil tank, the hydraulic pump being connected in series with a three-position four-way reversing valve relative to the oil tank via an oil circuit, the external port of the three-position four-way reversing valve being connected to a shuttle valve via an oil circuit, the side end of the shuttle valve being connected to a two-position two-way hydraulically controlled valve, the two-position two-way hydraulically controlled valve being connected in parallel with the oil tank to the oil circuit connecting the hydraulic pump and the internal port of the three-position four-way reversing valve.

[0006] Furthermore, the external ports of the three-position four-way reversing valve are divided into an A port and a B port; the A port is divided into two routes: one route is connected to an external device through an oil circuit; the other route is connected to one end of the shuttle valve through the oil circuit; the B port is divided into two routes: one route is connected to the external device through the oil circuit; the other route is connected to the other end of the shuttle valve through the oil circuit; the internal ports of the three-position four-way reversing valve are divided into a P port and a T port, the P port is connected to the output end of the hydraulic pump through the oil circuit, and the T port is connected to the oil tank through the oil circuit.

[0007] Furthermore, the C port of the two-position two-way hydraulic control valve is connected to the oil circuit connecting the P port and the hydraulic pump; the D port of the two-position two-way hydraulic control valve is connected to the oil circuit connecting the T port and the oil tank; the X port of the two-position two-way hydraulic control valve is connected to the oil circuit connecting the P port and the C port and is simultaneously connected to the output end of the hydraulic pump through the oil circuit; the Y port of the two-position two-way hydraulic control valve is connected to the side end of the shuttle valve.

[0008] Furthermore, the output end of the hydraulic pump is connected to a relief valve via an oil circuit, and the output end of the relief valve is connected to an oil tank via an oil circuit.

[0009] According to the above-mentioned hydraulic power station with unloading circuit, the specific steps of operation are as follows: S1. Connect the external port of the three-position four-way directional valve to the external device; S2. When the hydraulic power station is not in use, the three-position four-way reversing valve is in the middle position, that is, in the blocking state. The hydraulic oil in the oil tank will first be transported to the two-position two-way hydraulic control valve through the hydraulic pump, and the two-position two-way hydraulic control valve will be opened. Then, the hydraulic oil will flow back to the oil tank through the two-position two-way hydraulic control valve. At this time, the hydraulic power station is in the unloading state; S3. When the hydraulic power station starts to be used, the three-position four-way reversing valve is manually controlled to switch to the non-neutral position, that is, it is in a smooth state. The hydraulic oil in the oil tank will first be transported to the three-position four-way reversing valve through the hydraulic pump, and then transported to the shuttle valve through the external port of the three-position four-way reversing valve. The hydraulic oil is transported to the two-position two-way hydraulic control valve through the shuttle valve. The two-position two-way hydraulic control valve is closed, and the hydraulic oil will be transported to the external device through the external port of the three-position four-way reversing valve to enter the working state. S4. After the working state is completed, the three-position four-way reversing valve is manually controlled to switch to the middle position, and the hydraulic oil in the oil tank is transported to the two-position two-way hydraulic control valve through the hydraulic pump. The two-position two-way hydraulic control valve is opened again, and the hydraulic oil is returned to the oil tank through the two-position two-way hydraulic control valve to enter the unloading state.

[0010] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention realizes the function of automatic unloading of the hydraulic power station when not in use by cleverly designing a combination circuit of a three-position four-way reversing valve, a shuttle valve and a two-position two-way hydraulic control valve, effectively avoiding the overflow loss and heating problems caused by the need to maintain a certain pressure when the hydraulic power station is not in use, not only improving the overall efficiency of the hydraulic transmission system, but also extending the service life of the hydraulic components; through the transition design of the shuttle valve, the stability and continuity of the hydraulic oil during the transportation process are ensured, and the performance of the hydraulic transmission system is further improved. Compared with the existing electric control unloading method, the mechanical hydraulic control unloading circuit is adopted. The structure is relatively simple, no complex electric control system is required, the later maintenance cost is lower, the maintenance difficulty is also smaller, and the operation process is also simpler and more intuitive. Only by manually controlling the switching of the three-position four-way reversing valve, the start-up, working and unloading state of the hydraulic power station can be easily realized. There is no need to manually adjust the overflow valve frequently, thereby greatly improving the stability and reliability of unloading, effectively avoiding safety problems caused by staff misoperation, reducing the operation difficulty and working time, and better meeting the development requirements of the hydraulic power station; 2. The present invention utilizes the combined effect of the unloading circuit and the relief valve to enable the hydraulic power station to automatically adjust the working state when it does not need to run at full power, thereby reducing energy consumption and improving energy efficiency; and through reasonable oil circuit design and component layout, the hydraulic power station is more convenient and quick to maintain, reducing downtime and maintenance costs; 3. The present invention enables the hydraulic power station to realize rapid switching between multiple working modes through the connection of the A and B ports of the three-position four-way reversing valve with external equipment and the shuttle valve and the flexible control of the two-position two-way hydraulic control valve, thereby improving the flexibility and adaptability of the hydraulic power station. The Y port of the two-position two-way hydraulic control valve is connected to the side end of the shuttle valve and forms a parallel circuit with the hydraulic pump and the internal port of the three-position four-way reversing valve, so that the hydraulic power station can quickly open the hydraulic control valve when unloading is required, thereby reducing the pressure of the hydraulic power station, realizing the unloading function, reducing energy consumption and component wear, and adopting the setting of the overflow valve to ensure that the hydraulic power station can safely return excess hydraulic oil to the oil tank when the pressure exceeds the preset value, effectively avoiding damage and safety accidents caused by excessive pressure; 4. The present invention can realize the switching between the working state and the unloading state of the hydraulic power station through simple manual control. The operation steps of the hydraulic power station are clear and concise, which not only significantly reduces the energy consumption of the hydraulic system during non-working period, reduces the wear of hydraulic components, and prolongs the service life, but also reduces the difficulty of operation and improves the work efficiency. In the working state, the hydraulic oil can be stably delivered to the external equipment through the precise control of the three-position four-way reversing valve and the shuttle valve, which helps to improve the operating efficiency and stability of the external equipment; 5. The hydraulic power station provided by the present invention can flexibly adjust the output flow rate according to actual needs. When the external device needs hydraulic energy, the three-position four-way reversing valve is switched to a non-neutral state, and the hydraulic oil is stably output to the external device after adjustment through the shuttle valve and the two-position two-way hydraulic control valve; when the external device does not need hydraulic energy, the three-position four-way reversing valve is switched back to the neutral state, and the hydraulic power station automatically enters the unloading state, so that the hydraulic power station can better adapt to the needs under different working conditions, improve its adaptability and flexibility, not only meet the current industrial field for the stability and reliability of the hydraulic transmission system demand, but also by simplifying the operating process and reducing maintenance costs, improve the cost performance and competitiveness of the hydraulic power station, with a promotion effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a structural schematic diagram of the working principle of the present invention; Figure 2 It is a structural schematic diagram of the hydraulic power station of the present invention in an unloading state; Figure 3 It is a structural schematic diagram of the hydraulic power station of the present invention in a working state.

[0012] Among them: 1. Oil tank; 2. Hydraulic pump; 3. Three-position four-way reversing valve; 4. Shuttle valve; 5. Two-position two-way hydraulic control valve; 6. Overflow valve; A, A port of three-position four-way directional valve; B, B port of three-position four-way directional valve; P, P port of three-position four-way directional valve; T, T port of three-position four-way directional valve; C, C port of two-position two-way hydraulic control valve; D, D port of two-position two-way hydraulic control valve; Y, Y port of two-position two-way hydraulic control valve; X, X port of two-position two-way hydraulic control valve. DETAILED DESCRIPTION

[0013] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments, but does not limit the application of the present invention.

[0014] See also Figure 1-Figure 3 The present invention provides a hydraulic power station with an unloading circuit, comprising an oil tank 1 for providing hydraulic oil and a hydraulic pump 2 connected to the oil tank 1 and used for conveying hydraulic oil, the output end of the hydraulic pump 2 is connected to a relief valve 6 for adjusting system pressure through an oil circuit, the output end of the relief valve 6 is connected to the oil tank 1 through an oil circuit, the hydraulic pump 2 is connected in series with a three-position four-way reversing valve 3 for manual operation relative to the oil tank 1 through an oil circuit, the external port of the three-position four-way reversing valve 3 is connected to a shuttle valve 4 for transition through an oil circuit, the side end of the shuttle valve 4 is connected to a two-position two-way hydraulic control valve 5 for controlling unloading, the two-position two-way hydraulic control valve 5 is connected in parallel with the oil tank 1 to the oil circuit connecting the hydraulic pump 2 and the internal port of the three-position four-way reversing valve 3; The external ports of the three-position four-way reversing valve 3 are divided into one port connected to an external device through an oil circuit (the functions and structures of conventional devices such as external devices are well known in the art, and the connection settings are also common knowledge, so no further explanation is given here and it is not shown in the drawings) and the other port is connected to the A port at one end of the shuttle valve 4 through an oil circuit, and one port is connected to the external device through an oil circuit and the other port is connected to the B port at the other end of the shuttle valve 4 through an oil circuit; the internal ports of the three-position four-way reversing valve 3 are divided into a P port and a T port, the P port is connected to the output end of the hydraulic pump 2 through an oil circuit, and the T port is connected to the oil tank 1 through an oil circuit; The C port and D port of the two-position two-way hydraulic control valve 5 are respectively connected to the oil circuit connected between the P port and the hydraulic pump 2 and the oil circuit connected between the T port and the oil tank 1; the X port of the two-position two-way hydraulic control valve 5 is connected to the oil circuit connected between the P port and the C port and is simultaneously connected to the output end of the hydraulic pump 2 through the oil circuit; the Y port of the two-position two-way hydraulic control valve 5 is connected to the side end of the shuttle valve 4.

[0015] The working principle and use process of the present invention are as follows: Figure 1-Figure 3 As shown in the figure, after the assembly of the hydraulic power station with the unloading circuit is completed, the operator connects the overall structure of the hydraulic power station with the external equipment, and can easily realize the conversion between the start-up, working and unloading states of the hydraulic power station by manually controlling the switching of the three-position four-way reversing valve 3. Compared with the existing electric control unloading method, the structure is relatively simple, no complex electric control system is required, the later maintenance cost is lower, the maintenance difficulty is also smaller, and the operation process is simpler and more intuitive, and there is no need to manually adjust the overflow valve frequently, thereby greatly improving the stability and reliability of unloading, effectively solving the safety problems caused by the staff's misoperation, reducing the difficulty of operation and working time, and also solving the overflow loss and heating problems caused by the hydraulic power station still needing to maintain a certain pressure when not in use, which not only improves the overall efficiency of the hydraulic transmission system, but also prolongs the service life of the hydraulic components, and can better meet the development requirements of the hydraulic power station; When the hydraulic power station needs to be connected to an external device for hydraulic transmission, the operator first connects the two ends of the hydraulic pump 2 to the oil tank 1 and the P port of the three-position four-way reversing valve 3 through the oil circuit respectively, and then connects the T port of the three-position four-way reversing valve 3 to the oil tank 1 through the oil circuit, and the D port of the two-position two-way hydraulic control valve 5 is connected to the oil circuit connecting the oil tank 1 and the T port of the three-position four-way reversing valve 3, and the C port of the two-position two-way hydraulic control valve 5 is connected to the oil circuit connecting the P port of the three-position four-way reversing valve 3 and the hydraulic pump 2, and at the same time, the X port of the two-position two-way hydraulic control valve 5 is connected to the oil circuit connecting the C port of the two-position two-way hydraulic control valve 5 and the P port of the three-position four-way reversing valve 3, and then one of the A port and the B port of the three-position four-way reversing valve 3 is connected to the external device through the oil circuit and the other one is connected to the two ends of the shuttle valve 4 respectively, and then the side end of the shuttle valve 4 is connected to the Y port of the two-position two-way hydraulic control valve 5, and finally a hydraulic power station with an unloading circuit is formed; When the hydraulic power station is not in use, the initial state of the three-position four-way reversing valve 3 is in the middle position, that is, the P port of the three-position four-way reversing valve 3 is in the blocking state, and the hydraulic oil cannot enter the three-position four-way reversing valve 3 from the P port. Since the two-position two-way hydraulic control valve 5 is in the normally closed state, that is, the C port of the two-position two-way hydraulic control valve 5 and the D port of the two-position two-way hydraulic control valve 5 are in the disconnected state, the hydraulic oil in the oil tank 1 will first be transported to the X port of the two-position two-way hydraulic control valve 5 through the hydraulic pump 2, and then enter the two-position two-way hydraulic control valve 5 from the X port of the two-position two-way hydraulic control valve 5, so that the two-position two-way hydraulic control valve 5 is forced to move the valve core to the right under the action of the hydraulic oil until it is in the open state (that is, the C port and the D port are in the connected state). At this time, the hydraulic oil will flow from the C port of the two-position two-way hydraulic control valve 5 to the D port of the two-position two-way hydraulic control valve 5, and then return the hydraulic oil to the oil tank 1 from the D port of the two-position two-way hydraulic control valve 5, so that the hydraulic power station is in the unloading state (such as Figure 2 shown); When the hydraulic power station starts to be used, the three-position four-way directional valve 3 is manually controlled to switch to the non-neutral position, that is, the P port of the three-position four-way directional valve 3 is in an unobstructed state. At this time, the hydraulic oil can enter the three-position four-way directional valve 3 from the P port, and then be delivered to the external device through the three-position four-way directional valve 3. The specific direction of the hydraulic oil is as follows: the hydraulic oil in the oil tank 1 will first be delivered to the P port of the three-position four-way directional valve 3 through the hydraulic pump 2, and then enter the three-position four-way directional valve 3 from the P port of the three-position four-way directional valve 3, and then enter the shuttle valve 4 (the shuttle valve is in a normally closed state) from one of the external ports of the three-position four-way directional valve 3 (if port A is regarded as the oil inlet end, then port B is the oil delivery end, if port B is regarded as the oil inlet end, then port A is the oil delivery end), so that the shuttle valve 4 is forced to be in an open state under the action of the hydraulic oil, and the shuttle valve 4 is opened. After the shuttle valve 4 is opened, the hydraulic oil will enter the two-position two-way hydraulic control valve 5 from the Y port of the two-position two-way hydraulic control valve 5, so that the two-position two-way hydraulic control valve 5 is forced to move the valve core to the left under the action of the hydraulic oil until it is in a closed state (that is, the C port and the D port are in a disconnected state). After the closure, the C port of the two-position two-way hydraulic control valve 5 cannot allow the hydraulic oil to enter the D port, and the hydraulic oil cannot flow back to the oil tank 1. At this time, the hydraulic oil will be completely transported to the external device through the other port of the external port of the three-position four-way reversing valve 3 to work (such as Figure 3 shown); After the external equipment is finished working, the operator will manually control the three-position four-way reversing valve 3 to switch to the middle position, and the hydraulic oil in the external equipment will flow back from one of the external ports of the three-position four-way reversing valve 3 to the three-position four-way reversing valve 3, and then flow back from the T port of the three-position four-way reversing valve 3 to the oil tank 1, and the hydraulic oil in the oil tank 1 will be transported to the X port of the two-position two-way hydraulic control valve 5 through the hydraulic pump 2, and enter the two-position two-way hydraulic control valve 5 from the X port, and open the two-position two-way hydraulic control valve 5 again, so that the hydraulic oil flows from the C port of the two-position two-way hydraulic control valve 5 to the D port of the two-position two-way hydraulic control valve 5, and then the hydraulic oil flows back to the oil tank 1 from the D port of the two-position two-way hydraulic control valve 5, so that the hydraulic power station enters the unloading state again (such as Figure 2 shown); When the pressure of the hydraulic power station needs to be adjusted, it can be achieved by simply adjusting the output flow of the relief valve 6.

Claims

1. A hydraulic power station with an unloading circuit, comprising an oil tank and a hydraulic pump connected to the oil tank, characterized in that: The hydraulic pump is connected in series with a three-position four-way reversing valve relative to the oil tank through an oil circuit, the external port of the three-position four-way reversing valve is connected to a shuttle valve through an oil circuit, the side end of the shuttle valve is connected to a two-position two-way hydraulically controlled valve, and the two-position two-way hydraulically controlled valve is connected in parallel with the oil circuit connecting the hydraulic pump and the internal port of the three-position four-way reversing valve relative to the oil tank.

2. A hydraulic power station with a load-unloading circuit according to claim 1, characterized in that: The external ports of the three-position four-way reversing valve are divided into an A port and a B port.

3. A hydraulic power station with a load-unloading circuit according to claim 2, characterized in that: The A port is divided into two paths: one path is connected to an external device through an oil path; and the other path is connected to one end of a shuttle valve through an oil path.

4. A hydraulic power station with a load-unloading circuit according to claim 3, characterized in that: The B port is divided into two paths: one path is connected to an external device through an oil path; and the other path is connected to the other end of the shuttle valve through an oil path.

5. The hydraulic power station with a load-unloading circuit according to claim 1, characterized in that: The internal ports of the three-position four-way reversing valve are divided into a P port and a T port. The P port is connected to the output end of the hydraulic pump through an oil circuit, and the T port is connected to the oil tank through an oil circuit.

6. A hydraulic power station with a load-unloading circuit according to claim 5, characterized in that: The C port of the two-position two-way hydraulic control valve is connected to the oil circuit connecting the P port and the hydraulic pump, and the D port of the two-position two-way hydraulic control valve is connected to the oil circuit connecting the T port and the oil tank.

7. A hydraulic power station with a load-unloading circuit according to claim 6, characterized in that: The X port of the two-position two-way hydraulic control valve is connected to the oil circuit connecting the P port and the C port and is simultaneously connected to the output end of the hydraulic pump through the oil circuit.

8. A hydraulic power station with a load-unloading circuit according to claim 7, characterized in that: The Y port of the two-position two-way hydraulic control valve is connected to the side end of the shuttle valve.

9. A hydraulic power station with a load-unloading circuit according to claim 1, characterized in that: The output end of the hydraulic pump is also connected to a relief valve through an oil circuit, and the output end of the relief valve is connected to an oil tank through an oil circuit.

10. The method for operating a hydraulic power station with a load-unloading circuit according to any one of claims 1 to 9, characterized in that: The specific steps are as follows: S1. Connect the external port of the three-position four-way directional valve to the external device; S2. When the hydraulic power station is not in use, the three-position four-way reversing valve is in the middle position, that is, in the blocking state. The hydraulic oil in the oil tank will first be transported to the two-position two-way hydraulic control valve through the hydraulic pump, and the two-position two-way hydraulic control valve will be opened. Then, the hydraulic oil will flow back to the oil tank through the two-position two-way hydraulic control valve. At this time, the hydraulic power station is in the unloading state; S3. When the hydraulic power station starts to be used, the three-position four-way reversing valve is manually controlled to switch to the non-neutral position, that is, it is in a smooth state. The hydraulic oil in the oil tank will first be transported to the three-position four-way reversing valve through the hydraulic pump, and then transported to the shuttle valve through the external port of the three-position four-way reversing valve. The hydraulic oil is transported to the two-position two-way hydraulic control valve through the shuttle valve. The two-position two-way hydraulic control valve is closed, and the hydraulic oil will be transported to the external device through the external port of the three-position four-way reversing valve to enter the working state. S4. After the working state is completed, the three-position four-way reversing valve is manually controlled to switch to the middle position, and the hydraulic oil in the oil tank is transported to the two-position two-way hydraulic control valve through the hydraulic pump. The two-position two-way hydraulic control valve is opened again, and the hydraulic oil is returned to the oil tank through the two-position two-way hydraulic control valve to enter the unloading state.

Images