Pilot-controlled commutation circuit with one-way throttling fast reset unit

Abstract

The application discloses a pilot control reversing circuit with a one-way throttling quick reset unit, comprising an oil pump unit, a pilot control valve, a quick reset unit and a main reversing valve connected through oil paths in sequence, wherein the quick reset unit is arranged between the pilot control valve and the main reversing valve and comprises a cylinder body and a piston; a first end surface of the cylinder body is provided with an oil inlet, a second end surface is provided with a main connecting port, and a one-way throttle valve is arranged in the piston; a side wall of the cylinder body is provided with an oil return port close to the second end surface, and the oil return port is used for being connected with an oil tank. When the pilot control valve is opened, pressure oil flows into the cylinder body through the oil inlet and pushes the piston to move to abut against the second end surface, so that the pressure oil flows into the main reversing valve through the one-way throttle valve and the main connecting port to push the main reversing valve to reverse; when the pilot control valve is closed, pressure oil in the main reversing valve flows back to the cylinder body and pushes the piston to separate from the second end surface, so that the oil return port is opened, and pressure oil flows out through the oil return port to realize reset of the main reversing valve.

Description

Technical Field

[0001] This invention relates to the field of hydraulic control technology, and specifically to a pilot control commutation circuit with a one-way throttling and fast reset unit. Background Technology

[0002] The main function of a hydraulic reversing circuit is to change the direction of fluid flow and the direction of movement of hydraulic actuators. Reversing valves are generally used in hydraulic equipment to achieve this. The reversing circuit in hydraulic equipment is a core factor affecting the equipment's response speed. Due to its simple structure, few components, and sensitive reversing, the reversing valve is widely used in various types of hydraulic equipment.

[0003] However, in specialized fields such as deep space, deep earth, and deep sea, the working environment can vary from ambient temperature to 200℃ and from atmospheric pressure to 330MPa. Besides requiring hydraulic equipment to operate normally under such wide temperature and pressure conditions, it also demands high flow rate, fast response speed, and stable operation. Currently, very few products on the market meet the requirements of such wide temperature and pressure environments, and their diameters are all below 2mm, limiting their application range and making them unsuitable for high-flow-rate, high-speed operation. Because the viscosity of the liquid medium is greatly affected by changes in ambient temperature, the liquid resistance changes significantly when passing through small-diameter oil passages. This results in high return resistance through the small-diameter pilot control valve, restricting the reset speed of the main directional valve and thus limiting the movement speed of the actuator.

[0004] Therefore, there is an urgent need to develop a reversing circuit that can improve the reset speed of the reversing valve, so as to solve the problem that the reset speed of the main reversing valve and the movement speed of the actuator are limited by the small diameter of the pilot control valve and the limited application range. Summary of the Invention

[0005] This invention aims to at least solve one of the technical problems existing in the prior art. Therefore, in response to the above-mentioned problems, the object of this invention is to provide a pilot control reversing circuit with a one-way throttling rapid reset unit. By setting the rapid reset unit, the reset speed of the main reversing valve is not affected by the small diameter of the pilot control valve, thus achieving rapid reset of the main reversing valve. This improves the working efficiency and reliability of the reversing circuit and broadens the application range of hydraulic reversing circuits.

[0006] To achieve the above-mentioned objectives, the technical solution adopted by this invention is as follows: This invention provides a pilot control reversing circuit with a one-way throttling and quick reset unit. The pilot control reversing circuit includes an oil pump unit, a pilot control valve, a quick reset unit, and a main reversing valve connected sequentially via an oil circuit. The oil pump unit provides pressurized oil to the pilot control valve. The quick reset unit is disposed between the pilot control valve and the main reversing valve and includes a cylinder and a piston. The cylinder has an inlet port on its first end face for connection to the pilot control valve and a main connection port on its second end face for connection to the main reversing valve. The piston can slide between the first and second end faces of the cylinder. A one-way throttling valve is disposed inside the piston. A return port is provided on the side wall of the cylinder near the second end face, and the return port is used to connect to an oil tank. When the pilot control valve is opened, the pressurized oil flows into the cylinder through the oil inlet and pushes the piston to move against the second end face, so that the pressurized oil flows into the main reversing valve through the one-way throttle valve and the main connection port and pushes the main reversing valve to switch. When the pilot control valve is closed, the pressure oil in the main directional valve flows back to the cylinder and pushes the piston to separate from the second end face, so that the return port opens and the pressure oil flows out through the return port to reset the main directional valve.

[0007] In a preferred embodiment of the present invention, the quick reset unit is further provided with an elastic structure, which is disposed between the first end face of the cylinder and the piston. The elastic structure is in a compressed state, which can ensure that the piston is in a position that abuts against the second end face of the cylinder in the initial state.

[0008] In a preferred embodiment of the present invention, when the pilot control valve is closed, the thrust generated by the pressure oil in the main directional valve on the piston is greater than the preload of the elastic structure, which enables the piston to be pushed to separate from the second end face of the cylinder.

[0009] In a preferred embodiment of the present invention, when the piston abuts against the second end face of the cylinder, the pre-compression force of the elastic structure... F The following relationship must be satisfied: ; in, S This represents the axial projected area of ​​the piston. The oil pressure of the pressurized oil. This refers to the oil pressure in the oil tank. Frictional resistance exists during the piston's sliding process. The oil in the cylinder has axial hydraulic force during its flow.

[0010] In a preferred embodiment of the present invention, a first groove is provided on the end face of the piston facing the main connection port, and a first sealing ring is provided at the first groove. The thickness of the first sealing ring is greater than the depth of the first groove, so that when the piston moves to press against the second end face, there is a gap between the end face of the piston facing the main connection port and the second end face.

[0011] In a preferred embodiment of the present invention, the side wall of the piston is provided with a second groove, and a second sealing ring is provided at the second groove, and the piston and the cylinder are slidably sealed together by the second sealing ring.

[0012] In a preferred embodiment of the present invention, the pilot control valve includes a pilot inlet, a pilot outlet, and a pilot return port, wherein the pilot outlet is selectively connected to either the pilot inlet or the pilot return port, the oil pump unit is connected to the pilot inlet, and the pilot return port is connected to the oil tank.

[0013] In a preferred embodiment of the present invention, the one-way valve diameter of the one-way throttle valve is larger than the diameter of the first outlet port, the diameter of the oil passage is equal to the diameter of the first outlet port, and the diameter of the return port is larger than the diameter of the first outlet port.

[0014] In a preferred embodiment of the present invention, the main reversing valve includes a valve core and a valve sleeve. The valve sleeve has a cavity inside, and the valve core is slidably disposed in the cavity. The valve core divides the cavity into a control cavity and a moving cavity. The main connection port is connected to the control cavity through an oil circuit. The moving cavity includes a reversing return oil port, which is connected to the oil tank.

[0015] In a preferred embodiment of the present invention, the linear expansion coefficients of the materials used for the valve core and the valve sleeve are consistent.

[0016] Because the present invention adopts the above technical solution, it has the following characteristics: 1. This invention provides a rapid reset unit between the pilot control valve and the main directional valve. During the reset process, when the pressure oil flows back to the cylinder, it can push the piston to separate from the second end face of the cylinder, opening the return port T. This allows the pressure oil to flow out directly through the return port T, making the reset speed of the main directional valve unaffected by the small diameter of the pilot control valve. This enables rapid reset of the main directional valve in a wide temperature range, improving the working efficiency and reliability of the directional control circuit and broadening the application range of the hydraulic directional control circuit.

[0017] 2. This invention, by setting an elastic structure between the first end face of the cylinder and the piston, and ensuring that the elastic structure is in a compressed state, guarantees that the piston is initially positioned against the second end face. This facilitates rapid response at the beginning of the reversing process and improves operational stability. The pre-compression force of the elastic structure is set according to the force relationship of the piston during the reset process. F This allows the piston and the second end face to separate smoothly during the reset process, which is beneficial to the normal operation of the rapid reset unit.

[0018] 3. This invention, by setting the diameter of the one-way throttle valve to be larger than the diameter of the first outlet port, reduces the resistance of the pressurized oil flowing through the one-way throttle valve during the switching process of the pilot control valve opening, while maintaining effective pressure to enter the main directional valve. Simultaneously, during the reset process of the pilot control valve closing, when the pressurized oil flows through the rapid reset unit, the throttle orifice of the one-way throttle valve plays a throttling role, and the pressurized oil in the main directional valve can generate sufficient back pressure to push the piston to overcome the resistance of friction, spring force, etc., and move and separate from the second end face of the cylinder. This allows as much pressurized oil as possible to flow out through the larger diameter return port T, which is beneficial for the rapid reset of the main directional valve. At the same time, when the return oil is about to end, the piston approaches the second end face under the push of the elastic structure, and the return port T closes. At this time, the remaining small amount of pressurized oil can flow out through the throttle orifice of the one-way throttle valve through the pilot control valve, ensuring that the main directional valve is completely reset.

[0019] 4. In this invention, the pilot control valve is provided with a pilot return port and the main directional valve is provided with a directional return port. By setting the return port T, the pilot return port and the directional return port to be connected to the oil tank respectively, the internal components of each component in the directional circuit are connected to the external environment. During operation, the hydraulic pressure on each component in the directional circuit is the effective pressure to overcome the load. The pressure it bears from the environment is automatically balanced, so that the directional circuit can operate stably under a wide pressure environment and improve its adaptability to a wide pressure environment.

[0020] 5. In this invention, the valve sleeve and valve core are preferably made of materials with the same linear expansion coefficient, so that when the main directional valve is applied to different temperature conditions, the thermal deformation caused by temperature changes to the valve sleeve and valve core is consistent. This is beneficial to the stable operation of the valve sleeve and valve core in different temperature environments, realizes the stable operation of the directional circuit in a wide temperature environment, and improves its adaptability to ambient temperature.

[0021] In summary, this invention can be widely applied in hydraulic control. Attached Figure Description

[0022] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. Since the main directional valve in the reversing circuit primarily relies on the movement of the valve core to achieve reversing, for simplicity, a single-acting hydraulic cylinder is used in the drawings to represent the movement of the valve core and, in contrast, the main directional valve to explain the reversing working principle. This reversing circuit can be used in control systems with various actuators; for simplicity, a double-acting hydraulic cylinder is used in the drawings to represent the actuator to explain the control process of the reversing circuit. In the drawings: Figure 1 This is a schematic diagram of a pilot control commutation circuit with a unidirectional throttling fast reset unit according to an embodiment of the present invention. Figure 2 This is a schematic diagram illustrating the working process of the pilot control commutation circuit with a unidirectional throttling fast reset unit according to an embodiment of the present invention. Figure 3 This is a schematic diagram of the reset process of the pilot control commutation circuit with a unidirectional throttling fast reset unit according to an embodiment of the present invention. Figure 4 The following are simplified diagrams of two operating states of the pilot control commutation circuit with a unidirectional throttling fast reset unit according to an embodiment of the present invention, wherein: The attached diagram is labeled as follows: 1-oil pump unit; 2-pilot control valve; 3-quick reset unit; 31-cylinder body; 32-piston; 33-one-way throttle valve; 34-elastic structure; 4-main directional valve; 5-oil tank; 6-first oil outlet port; 7-first oil circuit; 8-second oil circuit; 9-third oil circuit; 10-oil inlet P; 11-main connection port A; 12-oil return port T; 13-first sealing ring; 14-second sealing ring. Detailed Implementation

[0023] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a specific order as described or illustrated, unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0024] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0025] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "above," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure.

[0026] To address the problem that changes in liquid viscosity due to ambient temperature variations in pilot-controlled directional control circuits limit the reset speed of the main directional valve and the movement speed of the actuators, thus restricting their application range, this invention provides a pilot-controlled directional control circuit with a one-way throttling and rapid reset unit. This circuit includes an oil pump unit, a pilot control valve, a rapid reset unit, and a main directional valve connected sequentially via an oil circuit. The oil pump unit supplies pressurized oil to the pilot control valve. The rapid reset unit, located between the pilot control valve and the main directional valve, includes a cylinder and a piston. The cylinder has an inlet on its first end face for connection to the pilot control valve and a main connection port on its second end face for connection to the main directional valve. The piston can move between the first and second end faces of the cylinder. The piston is slidable and equipped with a one-way throttle valve. A return port is located on the side wall of the cylinder near the second end face, connecting to the oil tank. When the pilot control valve is open, pressurized oil flows into the cylinder through the inlet and pushes the piston to press against the second end face. This allows the pressurized oil to flow through the one-way throttle valve and the main connection port into the main directional valve, driving it to switch directions. When the pilot control valve is closed, the pressurized oil in the main directional valve flows back into the cylinder and pushes the piston away from the second end face, opening the return port and allowing pressurized oil to flow out. This ensures the main directional valve is not affected by the small diameter of the pilot control valve and can quickly reset. Therefore, this invention improves working efficiency and reliability, and broadens the application range of the directional control circuit.

[0027] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0028] Example 1: As Figure 1 As shown, the pilot control reversing circuit with a one-way throttling fast reset unit provided in this embodiment includes an oil pump unit 1, a pilot control valve 2, a fast reset unit 3 and a main reversing valve 4 connected in sequence through an oil circuit, wherein the fast reset unit 3 is disposed between the pilot control valve 2 and the main reversing valve 4.

[0029] The oil pump unit 1 is used to provide hydraulic oil with the required pressure and flow rate to the reversing circuit. The oil circuit includes a first oil circuit 7, a second oil circuit 8, and a third oil circuit 9.

[0030] The quick reset unit 3 includes a cylinder body 31 and a piston 32 equipped with a one-way throttle valve 33. The first end face of the cylinder body 31 is provided with an oil inlet P10 connected to the pilot control valve 2 through a first oil passage 7. The second end face of the cylinder body 31 is provided with a main connection port A11 connected to the main reversing valve 4 through a second oil passage 8. The piston 32 is slidably connected to the inner wall of the cylinder body 31 between the first end face and the second end face. The side wall of the cylinder body 31 is provided with an oil return port T12 near the second end face. The oil return port T12 is connected to the oil tank 5 through a third oil passage 9.

[0031] like Figure 2 As shown, when the pilot control valve 2 is opened, the pressure oil flows out from the pilot control valve 2, flows into the cylinder 31 through the oil inlet P10 and pushes the piston 32 to move to the second end face of the cylinder 31, so that the pressure oil flows out through the one-way throttle valve 33 and the main connection port A11, and flows into the main reversing valve 4 through the second oil passage 8 to push the main reversing valve 4 to reverse. like Figure 3As shown, when the pilot control valve 2 is closed, the main directional valve 4 is reset under the action of the reset structure. The pressure oil in the main directional valve 4 flows back to the cylinder 31 and generates a large back pressure, pushing the piston 32 to separate from the second end face, so that the return port T12 opens. The pressure oil flows back to the oil tank 5 directly through the larger diameter return port T12 and the third oil passage 9. At the same time, when the return oil is about to end, the piston approaches the second end face of the cylinder 31 under the spring force, and the return port T12 closes. At this time, the remaining small amount of pressure oil can flow out through the throttle orifice of the one-way throttle valve 33 through the pilot control valve 2. Thus, the main directional valve 4 is not restricted by the small diameter of the pilot control valve 2 during the reset process, realizing the rapid and reliable reset of the main directional valve 4 in a wide temperature environment. The working performance is not affected by the change in hydraulic resistance caused by the change in oil viscosity, improving the environmental temperature adaptability and reliability of the directional circuit.

[0032] In summary, through the cycle of opening and closing the pilot control valve 2 described above, the rapid switching and resetting of the main directional valve 4 is achieved. Figure 4 As shown, in practical applications, the reversing circuit provided in this embodiment can be connected to actuators with different application requirements to achieve rapid reset of the main reversing valve 4, adapt to the application requirements of various actuators with different flow rates and diameters, improve the working efficiency and reliability of the reversing circuit, and broaden the application range of the hydraulic reversing circuit in a wide temperature and pressure environment.

[0033] In some possible embodiments, the quick reset unit 3 further includes an elastic structure 34, one end of which is disposed on the inner wall of the first end face of the cylinder 31, and the other end is disposed on the end face of the piston 32 facing the oil inlet P10. When the elastic structure 34 is in a compressed state, it can ensure that the piston 32 is in a position that presses against the second end face of the cylinder 31 in the initial state, which is beneficial to the rapid response at the beginning of the reversing stroke and improves the working stability.

[0034] In some possible embodiments, the piston 32 has a first groove on the end face facing the main connection port A11, and a first sealing ring 13 is provided at the first groove. The thickness of the first sealing ring 13 is greater than the depth of the first groove, so that when the piston 32 moves to abut against the second end face, there is a gap between the end face of the piston 32 facing the main connection port A11 and the second end face, so that the oil pressure of the pressure oil during the reset process acts on the end face of the piston 32 facing the main connection port A11, pushing the piston 32 to separate from the second end face.

[0035] Furthermore, the first sealing ring 13 is used to prevent radial leakage of pressurized oil when the piston 32 is pressed against the second end face. The material can be an axial O-ring made of high-temperature resistant rubber material, or other high-temperature resistant sealing materials, which are not limited here. The groove design between the first sealing ring 13 and the first groove can be a dovetail groove to keep the sealing ring fixed, or other special-shaped groove designs can be used, which are not limited here.

[0036] In some possible embodiments, when the pilot control valve 2 is closed, the thrust generated by the pressure oil in the main directional valve 4 on the piston 32 is greater than the pre-compression force of the elastic structure 34, which enables the piston 32 to be pushed to separate from the second end face.

[0037] Specifically, the axial projected area of ​​piston 32 is S The oil pressure of the pressurized oil is p c The oil pressure in tank 5 is p t Piston 32 experiences frictional resistance during sliding. The oil inside cylinder 31 experiences axial hydraulic force during its flow. F h When the piston 32 presses against the second end face, the pre-compression force of the elastic structure 34 F The following relationship must be satisfied: .

[0038] This allows the piston 32 and the second end face to separate smoothly during the reset process, which is beneficial to the normal operation of the rapid reset unit 3.

[0039] In some possible embodiments, the sidewall of the piston 32 is provided with a second groove, and a second sealing ring 14 is provided at the second groove. The piston 32 and the cylinder 31 are slidably sealed together by the second sealing ring 14. The second sealing ring 14 helps to prevent oil leakage between the sidewalls of the cylinder 31 and the piston 32, while also preventing axial movement of the piston 32.

[0040] Furthermore, the second sealing ring 14 can be a shaft combination sealing ring made of high-temperature resistant fluororubber material, or other high-temperature resistant sealing materials can be selected, which are not limited here.

[0041] In some possible embodiments, the pilot control valve 2 includes a pilot inlet, a pilot outlet 6, and a pilot return port. The pilot outlet 6 is selectively connected to either the pilot inlet or the pilot return port. The oil pump unit 1 is connected to the pilot inlet. The pilot outlet 6 is connected to the inlet P10 through the first oil passage 7. The pilot return port is connected to the oil tank 5.

[0042] When the pilot control valve 2 is opened, the pilot inlet port is connected to the pilot outlet port 6, thereby transmitting pressurized oil; when the pilot control valve 2 is closed, the pilot outlet port 6 is connected to the pilot return port, so that the pilot control valve 2 is filled with hydraulic oil, thereby automatically balancing with the ambient pressure and improving its adaptability to ambient pressure.

[0043] Specifically, the diameter of the one-way throttle valve 33 is larger than the diameter of the first outlet port 6, and the diameter of the first oil passage 7 is equal to the diameter of the first outlet port 6. This ensures that during the reversing process of the pilot control valve 2 opening, the pressurized oil flows through the through hole, the one-way throttle valve, and the oil passage without generating additional hydraulic resistance, which is beneficial for maintaining effective pressure when the pressurized oil enters the main reversing valve 4. The diameter of the return port T12 is larger than the diameter of the first outlet port 6, which helps reduce the resistance of the pressurized oil flowing out of the return port T12. At the same time, during the reset process of the pilot control valve 2, the pressurized oil flows through the quick reset unit. At this time, the one-way throttle valve acts as a hydraulic resistance, and the pressure oil in the main directional valve can generate sufficient back pressure, so that the piston 32 can overcome the resistance of spring force, friction force and other resistances and move and separate from the second end face, so that as much pressure oil as possible can flow out through the large-diameter return port T12. At the same time, when the return oil is about to end, the piston approaches the second end face under the push of the elastic mechanism 34, and the return port T12 is closed. At this time, the remaining small amount of pressure oil can flow out through the throttle orifice of the one-way throttle valve 33 through the pilot control valve, which is conducive to the rapid and reliable reset of the main directional valve 4.

[0044] In some possible embodiments, the main directional valve 4 includes a valve core and a valve sleeve. The valve sleeve has a cavity inside, and the valve core is slidably disposed in the cavity. The valve core divides the cavity into a control cavity and a moving cavity. The main connection port A11 is connected to the control cavity through the second oil circuit 8. The moving cavity includes a reversing return port, which is connected to the oil tank 5, so that the main directional valve 4 is filled with hydraulic oil. During operation, the hydraulic pressure on the main directional valve 4 is the effective pressure to overcome the load. It automatically balances the pressure of the environment, realizes stable operation of the reversing circuit in a wide pressure environment, and improves the environmental pressure adaptability.

[0045] Furthermore, the linear expansion coefficients of the materials used for the valve core and valve sleeve are consistent, such as 8-4PH stainless steel and Monel K500 alloy. This ensures that when the main directional valve 4 is applied to different temperature conditions ranging from room temperature to 200℃, the thermal deformation caused by temperature changes to the valve sleeve and valve core is consistent. This is beneficial for the stable operation of the valve sleeve and valve core under different temperature environments, enabling the directional valve circuit to operate stably in a wide temperature range and improving its adaptability to a wide temperature range. The specific material selection needs to be based on the actual application scenario and a preset allowable difference threshold to ensure normal operation performance within the actual temperature variation range. No specific limitations are imposed here.

[0046] Furthermore, the rapid reset unit 3 provided in this embodiment ensures that the main directional valve 4 is not constrained by the small diameter of the pilot control valve 2 during the reset process. The linear expansion coefficients of the materials used for the valve core and valve sleeve are consistent. In addition, the pilot return port, the directional return port, and the return port T are connected to the oil tank respectively, so that the environmental pressure inside and outside the directional valve circuit is automatically balanced. It is suitable for deep-earth areas where the ambient temperature and environmental pressure vary over a wide range, such as in drilling and logging. During the process of the rapid reset pilot control directional valve circuit going deep into the well, the environment it is in rises from the normal temperature and pressure at the surface to the high temperature and high pressure underground. The ambient temperature range in this field is from normal temperature to 200°C, and the ambient pressure range is from 0 to 330 MPa, or even higher.

[0047] Specifically, the rapid reset unit 3 provided in this embodiment enables the main directional valve 4 to be unrestricted by the small diameter of the pilot control valve 2 during the reset process. The valve core and valve sleeve of the main directional valve 4 are made of high-temperature resistant materials with equal or similar linear expansion coefficients, making them suitable for deep space environments where the ambient temperature varies over a wide range and the ambient pressure is relatively stable. For example, in a space station, the pilot control reversing circuit for rapid reset may be located inside or outside the space station. Inside the station, the environment is at normal pressure, while outside the station, the environment is in a high vacuum. When descending from the ground to the space environment at a distance of about 400 km, the surface temperature of the space station can reach about 150°C or even higher under direct sunlight. Therefore, the ambient temperature range of the pilot control reversing circuit for rapid reset can reach more than 150°C.

[0048] Specifically, in this embodiment, the pilot return port, the reversing return port, and the return port T are connected to the oil tank 5, so that the environmental pressure inside and outside the reversing circuit is automatically balanced. It is also suitable for deep-sea areas where the environmental pressure varies over a wide range and the environmental temperature is relatively stable, such as seabed exploration. During the operation of the pilot control reversing circuit on the seabed, the working pressure gradually increases from the normal pressure environment at sea level to a high-pressure environment of about 320 MPa. The diving depth is about 11,000 m. With the change of seawater depth, the environmental pressure varies from 0 to 320 MPa and the environmental temperature ranges from normal temperature to about 6°C.

[0049] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In the description of this specification, the terms "a preferred embodiment," "furthermore," "specifically," "in this embodiment," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the embodiments in this specification. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A pilot control commutation circuit with a unidirectional throttling fast reset unit, characterized in that, The pilot control reversing circuit includes an oil pump unit (1), a pilot control valve (2), a quick reset unit (3), and a main reversing valve (4) connected sequentially through an oil circuit. The oil pump unit (1) is used to supply pressurized oil to the pilot control valve (2); The quick reset unit (3) is disposed between the pilot control valve (2) and the main directional valve (4), and includes a cylinder (31) and a piston (32); wherein, the first end face of the cylinder (31) is provided with an oil inlet P (10) for connecting to the pilot control valve (2), and the second end face is provided with a main connection port A (11) for connecting to the main directional valve (4); the piston (32) can slide between the first end face and the second end face of the cylinder (31); a one-way throttle valve (33) is provided inside the piston (32); the side wall of the cylinder (31) is provided with an oil return port T (12) near the second end face, and the oil return port T (12) is used to connect to the oil tank (5); When the pilot control valve (2) is opened, the pressure oil flows into the cylinder (31) through the oil inlet P (10) and pushes the piston (32) to move to press against the second end face, so that the pressure oil flows into the main reversing valve (4) through the one-way throttle valve (33) and the main connection port A (11) and pushes the main reversing valve (4) to reverse. When the pilot control valve (2) is closed, the pressure oil in the main directional valve (4) flows back to the cylinder (31) and pushes the piston (32) to separate from the second end face, so that the return port T (12) opens and the pressure oil flows out through the return port T (12) to reset the main directional valve (4).

2. The pilot control commutation circuit according to claim 1, characterized in that, The quick reset unit (3) is also provided with an elastic structure (34), which is disposed between the first end face of the cylinder (31) and the piston (32). The elastic structure (34) is in a compressed state, which can ensure that the piston (32) is in a position that abuts against the second end face of the cylinder (31) in the initial state.

3. The pilot control commutation circuit according to claim 2, characterized in that, When the pilot control valve (2) is closed, the pressure oil in the main directional valve (4) generates a thrust on the piston (32) that is greater than the preload of the elastic structure (34), which enables the piston (32) to be pushed to separate from the second end face of the cylinder (31).

4. The pilot control commutation circuit according to claim 3, characterized in that, When the piston (32) abuts against the second end face of the cylinder (31), the pre-compression force of the elastic structure (34) F The following relationship must be satisfied: ； in, S This represents the axial projected area of ​​the piston. The oil pressure of the pressurized oil. This refers to the oil pressure in the oil tank. Frictional resistance exists during the piston's sliding process. The oil in the cylinder has axial hydraulic force during its flow.

5. The pilot control commutation circuit according to claim 1, characterized in that, The piston (32) has a first groove on its end face facing the main connection port A (11), and a first sealing ring (13) is provided in the first groove. The thickness of the first sealing ring (13) is greater than the depth of the first groove, so that when the piston (32) moves to press against the second end face, there is a gap between the end face of the piston (32) facing the main connection port A (11) and the second end face.

6. The pilot control commutation circuit according to claim 1, characterized in that, The piston (32) has a second groove on its side wall, and a second sealing ring (14) is provided at the second groove. The piston (32) and the cylinder (31) are slidably sealed together by the second sealing ring (14).

7. The pilot control commutation circuit according to claim 1, characterized in that, The pilot control valve (2) includes a pilot inlet, a pilot outlet (6) and a pilot return port. The pilot outlet (6) is connected to either the pilot inlet or the pilot return port. The oil pump unit (1) is connected to the pilot inlet, and the pilot return port is connected to the oil tank (5).

8. The pilot control commutation circuit according to claim 7, characterized in that, The one-way valve diameter of the one-way throttle valve (33) is larger than the diameter of the first outlet port (6), the diameter of the oil passage is equal to the diameter of the first outlet port (6), and the diameter of the return port T (12) is larger than the diameter of the first outlet port (6).

9. The pilot control commutation circuit according to claim 1, characterized in that, The main reversing valve (4) includes a valve core and a valve sleeve. The valve sleeve has a cavity inside. The valve core is slidably disposed in the cavity. The valve core divides the cavity into a control cavity and a moving cavity. The main connection port A (11) is connected to the control cavity through an oil circuit. The moving cavity includes a reversing return oil port, which is connected to the oil tank (5).

10. The pilot control commutation circuit according to claim 9, characterized in that, The valve core and the valve sleeve are made of materials with the same coefficient of linear expansion.

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