Electromagnetic reversing hydraulic control system with backpressure-free return function

Abstract

The utility model relates to the technical field of hydraulic control systems, in particular to an electromagnetic reversing hydraulic control system with a backpressure-free return function, which comprises a pressure oil inlet, an electromagnetic reversing hydraulic control system, an electromagnetic reversing hydraulic control system and an electromagnetic reversing hydraulic control system, the oil return opening is connected with the oil tank and used for oil liquid backflow; the inlet end of the hydraulic control one-way valve is connected with the pressure oil inlet, and the outlet end is connected with the load interface for controlling one-way flow of oil; the electromagnetic reversing valve is connected with a control oil way of the hydraulic control one-way valve and is used for reversely opening the hydraulic control one-way valve, so that the oil in the load interface returns to the oil return port without backpressure; the first overflow valve is connected to an oil supply path of the pressure oil inlet, and an outlet of the first overflow valve is connected to the oil return port; the hydraulic control one-way valve can be controlled to be conducted reversely through the electromagnetic reversing valve, so that oil liquid of the load connector directly returns to the oil return port without back pressure, the return speed of an execution element is remarkably increased, and energy loss is reduced.

Description

Technical Field

[0001] This application relates to the field of hydraulic control system technology, and in particular to an electromagnetic reversing hydraulic control system with back pressure-free retraction function. Background Technology

[0002] Hydraulic control systems are a technology that uses fluid pressure to transmit energy and achieve mechanical control. They are widely used in industrial equipment, aerospace, construction machinery, automobile manufacturing, shipbuilding, and other fields. The core principle is to convert mechanical energy into fluid pressure energy using a hydraulic pump, and then convert that pressure energy back into mechanical energy using actuators such as hydraulic cylinders or hydraulic motors, thereby driving the load to complete a predetermined movement or operation.

[0003] In traditional hydraulic systems, back pressure typically exists in the return oil circuit during the retraction of actuators. This leads to increased system energy loss, slow actuator retraction speed, and susceptibility to hydraulic shock under high load inertia, affecting system stability and component lifespan. This project aims to develop an electromagnetic reversing hydraulic control system with back pressure-free retraction to address these issues. Utility Model Content

[0004] In view of at least one of the above technical problems, this application provides an electromagnetic reversing hydraulic control system with back pressure-free retraction function, and adopts the following technical solution to solve the above problems.

[0005] According to one aspect of this application, an electromagnetic reversing hydraulic control system with a back pressure-free retraction function is provided, comprising:

[0006] Pressure oil inlet, used to connect to an external pressure oil source;

[0007] The return port connects to the oil tank and is used for oil return.

[0008] A hydraulically controlled check valve has its inlet end connected to a pressure oil inlet and its outlet end connected to a load interface, used to control the unidirectional flow of oil.

[0009] The electromagnetic directional valve is connected to the control oil circuit of the hydraulic check valve and is used to open the hydraulic check valve in the reverse direction so that the oil in the load interface returns to the return port without back pressure.

[0010] The first relief valve is connected to the oil supply line of the pressure oil inlet and its outlet is connected to the oil return port; and

[0011] The second relief valve is connected to the return oil circuit between the load port and the return oil port and is used for overload protection.

[0012] Preferably, it also includes a throttling shut-off valve, which is installed in the return oil circuit for emergency pressure relief.

[0013] Preferably, the solenoid directional valve is a two-position four-way valve, in which the first working position connects the pressure oil inlet to the control oil port of the hydraulic check valve, and in the second working position releases the control oil pressure of the hydraulic check valve to the return oil port.

[0014] Preferably, the hydraulic check valve automatically closes when the reverse force at the load interface exceeds the pressure of the first relief valve, and in its closed state, the second relief valve provides pressure relief protection.

[0015] Preferably, the load interface is directly connected to the return port through a hydraulic check valve under reverse force, and there is no back pressure element in the return oil circuit.

[0016] Preferably, the first relief valve and the second relief valve are set with different pressure thresholds to achieve graded pressure protection.

[0017] Preferably, the regulating end of the first overflow valve is also provided with a pressure regulating block for dynamically adjusting the system pressure.

[0018] Preferably, a pressure sensor is provided between the outlet end of the hydraulic check valve and the load interface to detect the pressure at the load interface and feed it back to the external control unit.

[0019] This application has the following technical effects:

[0020] This application can control the hydraulic check valve to reverse its flow via an electromagnetic directional valve, allowing the oil at the load interface to return directly to the return port without back pressure. This significantly improves the return speed of the actuator, reduces energy loss, and is suitable for applications requiring rapid return, such as the rapid descent of a hydraulic lifting system. Furthermore, by setting different pressure thresholds through the first and second relief valves, the supply and return oil circuits are protected respectively, addressing different degrees of pressure anomalies. This enhances system reliability and reduces damage to components caused by pressure fluctuations. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a system architecture diagram of this application.

[0023] Figure label:

[0024] 1. Hydraulic check valve; 2. Solenoid directional valve; 3. First relief valve; 4. Pressure oil inlet; 5. Throttling shut-off valve; 6. Oil return port; 7. Second relief valve; 8. Load interface. Detailed Implementation

[0025] Please see Figure 1 It should be understood that the structures, proportions, sizes, etc., illustrated in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and objectives of the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the technical terms used in this specification are merely for clarity and not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.

[0026] The specific embodiments of this application will now be described in detail with reference to the accompanying drawings. Numerous specific details are set forth in the following description to provide a thorough understanding of this application.

[0027] In this embodiment of the application, as Figure 1 As shown, an electromagnetic reversing hydraulic control system with back pressure-free retraction function is provided, comprising:

[0028] Pressure oil inlet 4 is used to connect to an external pressure oil source;

[0029] Oil return port 6 is connected to the oil tank for oil return;

[0030] The hydraulic check valve 1 has its inlet end connected to the pressure oil inlet 4 and its outlet end connected to the load interface 8, and is used to control the unidirectional flow of oil.

[0031] The electromagnetic reversing valve 2 is connected to the control oil circuit of the hydraulic control check valve 1 and is used to open the hydraulic control check valve 1 in reverse so that the oil in the load port 8 returns to the return port 6 without back pressure.

[0032] The first relief valve 3 is connected to the oil supply line of the pressure oil inlet 4, and its outlet is connected to the oil return port 6; and

[0033] The second relief valve 7 is connected to the return oil circuit between the load port 8 and the return oil port 6 and is used for overload protection.

[0034] It should be noted that this application can realize the functions of pressure oil access, distribution, load driving and safety protection. In particular, it has the ability to return the oil without back pressure at the load interface 8, which can improve the system flexibility and practicality.

[0035] Specifically, pressure oil inlet 4 serves as the connection port between the system and the external pressure oil source, responsible for introducing high-pressure oil to provide the power foundation for the operation of the entire system. Its specifications need to be selected according to the required flow and pressure of the system. For example, in common industrial hydraulic systems, pressure oil inlet 4 is compatible with pipeline connections that can withstand pressures of 10-30MPa and flow rates of 50-200L / min.

[0036] The inlet of the hydraulically controlled check valve 1 is connected to the pressure oil inlet 4, and the outlet is connected to the load port 8. Under normal operating conditions, it functions like a regular check valve, allowing oil to flow only from the pressure oil inlet 4 to the load port 8 to drive the load. Its internal valve core employs a conical structure to ensure good sealing performance, reduce oil leakage, and improve system efficiency. When there is no pressure in the control oil circuit, the valve core tightly adheres to the valve seat under the action of spring force and oil pressure, preventing reverse oil flow.

[0037] The solenoid directional valve 2 is connected to the control oil circuit of the hydraulic check valve 1. Its core function is to open the hydraulic check valve 1 in reverse when needed. When the solenoid directional valve 2 switches its working state, it inputs or releases control pressure oil to the control port of the hydraulic check valve 1. If the control port receives pressure oil, the control piston inside the hydraulic check valve 1 will be pushed, thereby opening the valve core, allowing the oil in the load port 8 to flow back in reverse. Since there is no back pressure element in the return oil circuit, it achieves a back pressure-free return to the return port 6.

[0038] The first relief valve 3 is connected to the oil supply line of the pressure oil inlet 4, and its outlet leads to the return oil port 6. During system operation, if the oil supply line pressure rises abnormally and exceeds the preset pressure threshold of the first relief valve 3, the relief valve opens to release excess oil back to the oil tank, thereby preventing damage to the oil supply line due to excessive pressure. For example, the first relief valve 3 can be set to open for relief when the system pressure reaches 16MPa, ensuring that the oil supply line pressure is always maintained within a safe range.

[0039] The second relief valve 7 is connected to the return oil circuit between the load port 8 and the return oil port 6, and is mainly used to deal with possible overload situations at the load end. When the return oil pressure at the load port 8 becomes too high due to abnormal force or other reasons, exceeding the set pressure of the second relief valve 7, the valve opens to overflow, preventing excessive pressure from damaging system components and providing overload protection. Its set pressure is generally slightly higher than the return oil circuit pressure during normal system operation, such as 12MPa.

[0040] In one embodiment of this application, a throttling shut-off valve 5 is also included, which is disposed in the return oil circuit for emergency pressure relief.

[0041] It should be noted that the throttle valve 5, installed in the system's return oil circuit, adds an emergency pressure relief function, enhancing the system's safety and reliability in emergencies and preventing serious malfunctions caused by abnormal pressure accumulation. Specifically, the throttle valve 5 is installed in the return oil circuit and is selected as a valve type with good throttling characteristics and shut-off function. During normal operation, the throttle valve 5 can adjust the return oil flow rate according to system requirements, ensuring stable system operation. In case of an emergency, such as a sudden blockage of a component causing a sharp rise in return oil pressure, the throttle valve 5 can be quickly opened to its maximum opening manually or via an emergency control signal, rapidly releasing the high-pressure oil in the return oil circuit to achieve emergency pressure relief and prevent damage to the system from excessive pressure. Its diameter needs to be determined based on the system's maximum return oil flow rate to ensure timely and effective pressure relief in emergency situations. For example, in systems with large flow rates, a throttle valve 5 with a diameter of 20-30mm may be selected.

[0042] In one embodiment of this application, the electromagnetic reversing valve 2 is a two-position four-way valve. Its first working position connects the pressure oil inlet 4 to the control oil port of the hydraulic control check valve 1, and its second working position releases the control oil pressure of the hydraulic control check valve 1 to the return oil port 6.

[0043] It should be noted that the two-position four-way solenoid directional valve 2 can accurately and efficiently control the control oil pressure of the hydraulic check valve 1, realizing the switching of the working state of the hydraulic check valve 1, and thus achieving the conversion between the back pressure-free return of the oil at the load interface 8 and the normal working mode. Specifically, the two-position four-way solenoid directional valve 2 has four ports and two working positions. In the first working position, its internal oil circuit structure connects the pressure oil inlet 4 to the control oil port of the hydraulic check valve 1. The pressure oil enters the control oil port, pushes the control piston inside the hydraulic check valve 1, opens the valve core, and creates conditions for the reverse flow of the oil at the load interface 8. In the second working position, the solenoid directional valve 2 connects the control oil port of the hydraulic check valve 1 to the return oil port 6. The pressure oil at the control oil port is released, and the hydraulic check valve 1 closes the valve core under the action of the spring force, restoring the one-way conduction state and preventing the reverse flow of the oil. The rated operating pressure of the solenoid directional valve 2 must match the system pressure. For example, if the system pressure is 20 MPa, the rated pressure of the solenoid directional valve 2 should not be lower than 20 MPa, and its switching response time should be set between a few milliseconds and tens of milliseconds to achieve fast and accurate control.

[0044] In one embodiment of this application, the hydraulic check valve 1 automatically closes when the reverse force of the load interface 8 exceeds the pressure of the first relief valve 3, and in its closed state, the second relief valve 7 provides pressure relief protection.

[0045] It should be noted that the hydraulic check valve 1 works in conjunction with the first relief valve 3 and the second relief valve 7 to ensure unidirectional flow and load drive during normal operation, while also providing automatic closure and pressure relief protection under abnormal conditions, ensuring safe and stable system operation. Specifically, when the load port 8 is subjected to a reverse force, and the pressure generated by this reverse force exceeds the set pressure of the first relief valve 3, the system oil supply pressure cannot be maintained. The hydraulic check valve 1 automatically closes under its own spring force and the reverse oil pressure, preventing the oil from flowing backward and preventing damage to the load due to reverse pressure impact. Even with the hydraulic check valve 1 closed, if the pressure at the load port 8 continues to rise and exceeds the set pressure of the second relief valve 7, the second relief valve 7 opens, releasing the high-pressure oil from the load end back to the oil tank, providing pressure relief protection for the system. For example, the first relief valve 3 is set to a pressure of 15 MPa, and the second relief valve 7 is set to a pressure of 13 MPa. When the reverse pressure at the load port 8 reaches 16 MPa, the hydraulic check valve 1 closes; if the pressure continues to rise to 14 MPa, the second relief valve 7 opens to release pressure.

[0046] In one embodiment of this application, the load interface 8 is directly connected to the return oil port 6 through the hydraulic check valve 1 under the reverse force, and there is no back pressure element in the return oil circuit.

[0047] It should be noted that the load port 8 can directly connect to the return port 6 under reverse force without back pressure. This allows the system to operate quickly and smoothly when unloading or retracting the load, reducing energy loss and improving system response speed and operating efficiency. Specifically, in the system design, when the solenoid directional valve 2 switches to the working state that reverses the flow of the hydraulic check valve 1, a direct oil circuit is formed between the load port 8 and the return port 6, and no components such as throttle valves or back pressure valves that would generate back pressure are installed on this return oil circuit. This means that when the load port 8 is subjected to reverse force, the oil can flow back to the oil tank with minimal resistance. For example, in some hydraulic lifting systems with high speed requirements, this back pressure-free retraction design allows the lifting platform to fall quickly during descent, improving work efficiency.

[0048] In one embodiment of this application, the first relief valve 3 and the second relief valve 7 are respectively set with different pressure thresholds to achieve graded pressure protection.

[0049] It should be noted that the first relief valve 3 and the second relief valve 7 are set with different pressure thresholds to achieve graded pressure protection. This allows for more precise response to abnormal pressure conditions under different operating conditions, improving system reliability and safety, while reducing damage to system components caused by pressure fluctuations. Specifically, the first relief valve 3 primarily protects the system's oil supply line pressure, with a relatively high set pressure threshold, such as 18 MPa. When the system's oil supply line pressure abnormally rises to 18 MPa due to pump failure, sudden load changes, or other reasons, the first relief valve 3 opens, releasing excess oil back to the oil tank to prevent further pressure increases and protect components such as the pump and pipelines. The second relief valve 7 focuses on pressure protection for the load interface 8 and the return oil line, with a relatively low set pressure threshold, such as 12 MPa. When overload or impact occurs at the load end, causing the return oil line pressure to rise to 12 MPa, the second relief valve 7 opens to overflow, preventing excessive pressure from damaging the actuators connected to the load interface 8 and other components in the return oil line. Through this graded pressure protection design, the system can more effectively cope with pressure anomalies of different degrees.

[0050] In one embodiment of this application, the regulating end of the first overflow valve 3 is further provided with a pressure regulating block for dynamically adjusting the system pressure.

[0051] It should be noted that a pressure regulating block is installed at the regulating end of the first relief valve 3, providing a means for dynamic adjustment of the system pressure. This allows the system to flexibly change the pressure setting according to actual working needs, improving the system's adaptability and operational stability under different working conditions. Specifically, the pressure regulating block can be connected to the regulating end of the first relief valve 3 via threaded adjustment or knob adjustment. When the system needs to adjust the oil supply pressure, the pre-compression of the spring inside the first relief valve 3 can be changed by rotating the pressure regulating block. For example, when the system pressure needs to be increased, rotating the pressure regulating block clockwise increases the spring pre-compression, raising the opening pressure of the first relief valve 3; conversely, rotating the pressure regulating block counterclockwise decreases the spring pre-compression, lowering the opening pressure. The adjustment accuracy of the pressure regulating block is set to 0.1-0.5 MPa, which can meet the system's need for fine pressure adjustment. In some hydraulic test systems that require frequent pressure adjustments, the pressure regulating block allows operators to quickly adjust the system pressure according to test requirements.

[0052] In one embodiment of this application, a pressure sensor is provided between the outlet end of the hydraulic check valve 1 and the load interface 8 to detect the pressure of the load interface 8 and feed it back to the external control unit.

[0053] It should be noted that a pressure sensor is installed between the outlet of the hydraulic check valve 1 and the load interface 8 to monitor the pressure at the load interface 8 in real time and feed the pressure data back to the external control unit. This provides crucial information for the system's automated control and fault diagnosis, contributing to the intelligent operation and precise control of the system. Specifically, a high-precision, fast-response model of pressure sensor is selected, and its measurement range must cover the possible pressure variations at the load interface 8, for example, between 0-25 MPa. The pressure sensor converts the real-time pressure at the load interface 8 into an electrical signal, which is transmitted to the external control unit, such as a programmable logic controller (PLC), via a signal line. The control unit analyzes and processes the received pressure data. If the pressure exceeds the preset normal range, corresponding control measures can be taken, such as adjusting the oil pump output flow or switching the operating state of the solenoid directional valve 2, to ensure the normal operation of the system. Simultaneously, the pressure data can also be used for fault diagnosis. When abnormal pressure fluctuations occur in the system, the control unit can quickly locate the fault point based on the data fed back by the pressure sensor, such as determining whether there is a load overload or blockage of the hydraulic check valve 1.

[0054] The above are merely preferred embodiments of this application and do not constitute any limitation on this application. Any person skilled in the art can make many possible variations and modifications to the technical solution of this application, or modify it into equivalent embodiments, without departing from the scope of the technical solution of this application. Therefore, all equivalent changes made based on the shape, structure, and principle of this application without departing from the content of the technical solution of this application should be covered within the protection scope of this application.

Claims

1. An electromagnetic reversing hydraulic control system with back pressure-free retraction function, characterized in that, include: Pressure oil inlet (4) is used to connect to an external pressure oil source; Oil return port (6) is connected to the oil tank for oil return; The hydraulic control check valve (1) has its inlet end connected to the pressure oil inlet (4) and its outlet end connected to the load interface (8) for controlling the unidirectional flow of oil. The electromagnetic reversing valve (2) is connected to the control oil circuit of the hydraulic control check valve (1) and is used to open the hydraulic control check valve (1) in reverse so that the oil in the load port (8) returns to the return port (6) without back pressure. The first relief valve (3) is connected to the oil supply line of the pressure oil inlet (4), and its outlet is connected to the return oil port (6); and The second relief valve (7) is connected to the return oil circuit between the load port (8) and the return oil port (6) for overload protection.

2. The electromagnetic reversing hydraulic control system with back pressure-free retraction function according to claim 1, characterized in that: It also includes a throttling shut-off valve (5), which is installed in the return oil circuit for emergency pressure relief.

3. The electromagnetic reversing hydraulic control system with back pressure-free retraction function according to claim 1, characterized in that: The electromagnetic reversing valve (2) is a two-position four-way valve. Its first working position connects the pressure oil inlet (4) to the control oil port of the hydraulic control check valve (1), and its second working position releases the control oil pressure of the hydraulic control check valve (1) to the return oil port (6).

4. The electromagnetic reversing hydraulic control system with back pressure-free retraction function according to claim 1, characterized in that: The hydraulic control check valve (1) automatically closes when the reverse force of the load interface (8) exceeds the pressure of the first relief valve (3), and in its closed state, it is protected by the second relief valve (7) for pressure relief.

5. The electromagnetic reversing hydraulic control system with back pressure-free retraction function according to claim 1, characterized in that: The load interface (8) is directly connected to the return oil port (6) through the hydraulic check valve (1) under the reverse force, and there is no back pressure element in the return oil circuit.

6. The electromagnetic reversing hydraulic control system with back pressure-free retraction function according to claim 1, characterized in that: The first relief valve (3) and the second relief valve (7) are respectively set with different pressure thresholds to achieve graded pressure protection.

7. The electromagnetic reversing hydraulic control system with back pressure-free retraction function according to claim 1, characterized in that: The first overflow valve (3) is also equipped with a pressure regulating block at its regulating end for dynamically adjusting the system pressure.

8. The electromagnetic reversing hydraulic control system with back pressure-free retraction function according to claim 1, characterized in that: A pressure sensor is provided between the outlet end of the hydraulic check valve (1) and the load interface (8) to detect the pressure of the load interface (8) and feed it back to the external control unit.

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