Normally closed solenoid pilot control valve

Abstract

The present application provides a normally closed electromagnetic pilot control valve, which includes a main valve unit and an electromagnetic pilot valve unit, wherein the main valve unit is provided with an inlet and an outlet; the main valve unit is connected to the inlet end of the electromagnetic pilot valve unit through a medium inflow channel, the first outlet end of the electromagnetic pilot valve unit is connected to the open cavity inside the main valve unit through a first medium outflow channel, and the second outlet end of the electromagnetic pilot valve unit is connected to the closed cavity inside the main valve unit through a second medium outflow channel; the open cavity and the closed cavity are relatively isolated; the electromagnetic pilot valve unit is provided with a first exhaust port and a second exhaust port; the electromagnetic pilot valve unit is used to open or close the communication channel between the electromagnetic pilot valve unit and the main valve unit, so that the working medium flowing in through the inlet can drive the inlet and the outlet to be connected or disconnected, so as to realize the opening or closing of the main valve unit. The present application can realize the action requirements of self-control opening or closing through the working medium, and can eliminate the dependence on the control system.

Description

Technical Field

[0001] The present application belongs to the field of control valves, and specifically relates to a normally closed electromagnetic pilot control valve. Background Art

[0002] Electromagnetic pilot control valves can be widely used in the propellant supply system of aerospace engines at normal temperature. The valves used in the propellant supply system of rocket engines usually require high-pressure control gas as the control element, which requires the addition of a control system, for example, a control system composed of components such as gas cylinders with high-pressure control gas, conduits and control valves. Since adding a control system will not only increase the engine structure, layout and weight, the control system will also have problems such as insufficient gas source to control the valve due to leakage, making it difficult to meet the use requirements of commercial aerospace; therefore, the inventors of this application discovered during the research and development process that it is necessary to seek technical breakthroughs in valve structure to achieve the action requirements of the engine valve itself to control the opening or closing, and reduce dependence on the control system. Summary of the invention

[0003] In order to overcome the problems existing in the related art at least to a certain extent, the present application provides a normally closed electromagnetic pilot control valve.

[0004] According to an embodiment of the present application, the present application provides a normally closed electromagnetic pilot control valve, which includes a main valve unit and an electromagnetic pilot valve unit, wherein the main valve unit is provided with an inlet and an outlet, wherein the inlet is used to allow a working medium to pass through, and the outlet is used to discharge the working medium;

[0005] The main valve unit is connected to the inlet end of the electromagnetic pilot valve unit through a medium inflow channel, the first outlet end of the electromagnetic pilot valve unit is connected to the open cavity inside the main valve unit through a first medium outflow channel, and the second outlet end of the electromagnetic pilot valve unit is connected to the closed cavity inside the main valve unit through a second medium outflow channel; the open cavity and the closed cavity are relatively isolated;

[0006] The electromagnetic pilot valve unit is provided with a first exhaust port and a second exhaust port; the first exhaust port is used to exhaust the residual medium in the closed cavity, and the second exhaust port is used to exhaust the residual medium in the open cavity;

[0007] The electromagnetic pilot valve unit comprises a left valve cover, a right valve cover and a pilot housing; the left valve cover and the right valve cover are respectively fixedly connected to the two ends of the pilot housing in the length direction; the pilot housing is provided with a first assembly hole, a through hole, a second assembly hole and a third assembly hole, the first assembly hole is communicated with the second assembly hole through the through hole, and the second assembly hole is communicated with the third assembly hole through a first connecting channel; an exhaust valve core is provided in the first assembly hole, a push rod is provided in the through hole, a pilot valve is provided in the second assembly hole, and an electromagnetic valve is provided in the third assembly hole; the exhaust valve core is connected to the pilot valve through the push rod;

[0008] After the solenoid valve is powered on and opened, the working medium enters the open cavity through the communication channel between the inlet cavity connected to the inlet and the pilot valve, the communication channel between the pilot valve and the solenoid valve, and the communication channel between the solenoid valve and the open cavity. The working medium in the open cavity controls the inlet cavity connected to the inlet to communicate with the outlet cavity connected to the outlet, and the residual medium in the closed cavity is discharged through the first exhaust port.

[0009] After the solenoid valve is powered off and closed, the working medium enters the closing chamber through the connecting passage between the pilot valve and the push rod and the exhaust valve core and the connecting passage between the exhaust valve core and the closing chamber. The working medium in the closing chamber controls the separation between the inlet chamber and the outlet chamber. The working medium remaining in the open chamber is discharged through the connecting passage between the open chamber and the solenoid valve and the second exhaust port.

[0010] In the above-mentioned normally closed electromagnetic pilot control valve, the main valve unit comprises a main housing, a main valve core, a main spring and a piston; the main housing is provided with the inlet chamber, the outlet chamber and the control chamber which can communicate with each other;

[0011] The inlet is arranged at the inlet chamber, and the inlet chamber is connected to the inlet end of the electromagnetic pilot valve unit through the medium inflow channel; the outlet is arranged at the outlet chamber, and the control chamber is connected to the first outlet end of the electromagnetic pilot valve unit through the first medium outflow channel, and is connected to the second outlet end of the electromagnetic pilot valve unit through the second medium outflow channel;

[0012] The main valve core spans the inlet chamber, the outlet chamber and the control chamber along the length direction of the main housing, and the main valve core forms a seal with the side wall of the main housing at the connection between the inlet chamber and the outlet chamber, which is used to control the opening and closing of the inlet chamber and the outlet chamber; the main valve core forms another seal with the side wall of the main housing near the control chamber, which is used to control the opening and closing of the outlet chamber and the control chamber;

[0013] The main spring is arranged in the inlet chamber, one end of the main spring is connected to the side wall of the inlet chamber along the length direction of the main housing, the other end of the main spring is connected to one end of the main valve core, the other end of the main valve core is connected to the piston, and the main valve core can move along the length direction of the main housing under the push of the piston;

[0014] The piston is arranged in the control chamber, and a first sealing ring is sleeved on the outer side of the piston along the circumference of the piston. The piston and the first sealing ring separate the control chamber into an open chamber and a closed chamber; the open chamber is arranged on a side of the piston away from the outlet chamber, and the closed chamber is arranged on a side of the piston close to the outlet chamber.

[0015] Furthermore, the main valve core includes a sealing head and a push rod connected to the sealing head, and the sealing head is used to seal the connection between the inlet cavity and the outlet cavity.

[0016] Furthermore, a second sealing ring is sleeved on the side wall of the push rod at the opposite end close to the end where the push rod is connected to the head, and the second sealing ring is used to form a seal between the outlet cavity and the closing cavity to isolate the outlet cavity and the closing cavity.

[0017] Furthermore, along the length direction of the pilot housing, the first assembly hole is arranged in the pilot housing at one end where the pilot housing is connected to the left valve cover, and the second assembly hole is arranged at one end where the pilot housing is connected to the right valve cover; the second assembly hole is connected to the inlet chamber through the medium inflow channel;

[0018] Along the height direction of the pilot housing, the third assembly hole is arranged at the top of the pilot housing.

[0019] Further, the pilot valve includes a pilot valve core and a first spring, a left spring hole is provided at one end of the pilot valve core close to the right valve cover, and a right spring hole is provided at one end of the right valve cover close to the pilot housing corresponding to the left spring hole, and when the right valve cover is docked with the pilot housing, the left spring hole and the right spring hole constitute a first spring cavity, and the first spring is provided in the first spring cavity, and the first spring is used to push the pilot valve core to move in the second assembly hole.

[0020] Furthermore, the solenoid valve includes an electromagnetic housing and a coil, a second spring and a solenoid valve core arranged in the electromagnetic housing; the electromagnetic housing is provided with the second spring chamber and the valve core chamber which are interconnected, the second spring is arranged in the second spring chamber, the solenoid valve core is arranged in the valve core chamber, and the second spring is used to push the solenoid valve core to move in the valve core chamber.

[0021] In the above-mentioned normally closed electromagnetic pilot control valve, the first assembly hole includes a first guide hole and a first mounting hole, and the diameter of the first guide hole is smaller than the diameter of the first mounting hole;

[0022] A third sealing ring is sleeved on the part of the exhaust valve core located in the first guide hole; a first left cavity is formed between the part of the exhaust valve core located in the first mounting hole and the inner wall of the pilot housing where the first mounting hole is located, and the third sealing ring is used to enhance the sealing between the first left cavity and the closing cavity.

[0023] In the above-mentioned normally closed electromagnetic pilot control valve, the second assembly hole includes a second guide hole and a second mounting hole, the diameter of the second guide hole is smaller than the diameter of the second mounting hole; the part of the pilot valve core located in the second guide hole is sleeved with a fourth sealing ring; a first right cavity is formed between the part of the pilot valve core located in the second mounting hole and the inner wall of the pilot housing where the second assembly hole is located; the fourth sealing ring is used to enhance the sealing between the first right cavity and the open cavity.

[0024] In the above-mentioned normally closed electromagnetic pilot control valve, a first flow channel is arranged inside the push rod, a second flow channel is arranged inside the exhaust valve core, one end of the second flow channel is connected to the first flow channel, and the other end thereof is connected to the second medium outflow channel.

[0025] According to the above-mentioned specific embodiments of the present application, it can be known that at least the following beneficial effects are achieved: the normally closed electromagnetic pilot control valve provided by the present application is provided with a main valve unit and an electromagnetic pilot valve unit, the main valve unit is connected to the inlet end of the electromagnetic pilot valve unit through a medium inflow channel, the first outlet end of the electromagnetic pilot valve unit is connected to the open cavity inside the main valve unit through a first medium outflow channel, and the second outlet end of the electromagnetic pilot valve unit is connected to the closed cavity inside the main valve unit through a second medium outflow channel; the open cavity and the closed cavity are relatively isolated; the electromagnetic pilot valve unit uses electromagnetic force to open or close the communication channel between it and the main valve unit, so that the working medium flowing in through the inlet can drive the inlet and outlet to be connected or disconnected, so as to realize the opening or closing of the main valve unit; the electromagnetic pilot control valve provided by the present application is opened or closed with the help of the working medium when working, without the help of high-pressure control gas and control system, which can simplify the structure of the engine and reduce some weight.

[0026] It should be understood that the above general description and the following specific embodiments are only exemplary and illustrative and do not limit the scope of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The attached drawings below are part of the specification of the present application, which illustrate embodiments of the present application. The attached drawings together with the description of the specification are used to explain the principles of the present application.

[0028] Figure 1 A schematic structural diagram of a normally closed electromagnetic pilot control valve provided for a specific implementation of the present application.

[0029] Figure 2 A structural schematic diagram of an open state of a normally closed electromagnetic pilot control valve provided for a specific implementation of the present application.

[0030] Figure 3 A structural schematic diagram of a normally closed electromagnetic pilot control valve in a closed state provided for a specific implementation manner of the present application.

[0031] Description of reference numerals:

[0032] 1. Main valve unit;

[0033] 11. Entrance; 12. Exit;

[0034] 13. Main housing; 131. Inlet chamber; 132. Outlet chamber; 133. Control chamber; 1331. Open chamber; 1332. Close chamber; 134. Valve cover;

[0035] 14. Main valve core; 141. End cap; 142. Push rod;

[0036] 15. Main spring; 16. Piston; 17. First sealing ring; 18. Second sealing ring;

[0037] 2. Solenoid pilot valve unit;

[0038] 201, first exhaust port; 202, second exhaust port;

[0039] 21. Left valve cover; 22. Right valve cover;

[0040] 23. pilot housing; 231. through hole; 232. first exhaust passage;

[0041] 24, exhaust valve core; 241, third sealing ring; 242, first left cavity;

[0042] 25, pilot valve core; 251, fourth sealing ring; 252, first right cavity; 2521, first connecting channel; 2522, second connecting channel; 253, second right cavity;

[0043] 26. first spring; 261. first spring chamber;

[0044] 27. Ejector rod;

[0045] 28. Electromagnetic housing;

[0046] 281, coil;

[0047] 282, second spring; 2821, second spring chamber;

[0048] 283, solenoid valve core; 2831, valve core cavity;

[0049] 284, second exhaust passage;

[0050] 3. The medium flows into the channel;

[0051] 4. A first medium outflow channel;

[0052] 5. Second medium outflow channel. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical solutions and advantages of the embodiments of the present application more clearly understood, the spirit of the contents disclosed in the present application will be clearly explained with the accompanying drawings and detailed descriptions below. After understanding the embodiments of the contents of the present application, any technician in the relevant technical field can change and modify them according to the techniques taught by the contents of the present application without departing from the spirit and scope of the contents of the present application.

[0054] The exemplary embodiments and descriptions of the present application are used to explain the present application, but are not intended to limit the present application. In addition, elements / components with the same or similar reference numerals used in the drawings and embodiments are used to represent the same or similar parts.

[0055] The terms “first”, “second”, etc. used in this document do not particularly refer to an order or sequence, nor are they used to limit this application. They are only used to distinguish elements or operations described with the same technical terms.

[0056] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0057] As used herein, "and / or" includes any or all combinations of the items described.

[0058] As used herein, “plurality” includes “two” and “more than two”; as used herein, “plurality groups” includes “two groups” and “more than two groups”.

[0059] Certain terms used to describe the present application are discussed below or elsewhere in this specification to provide additional guidance to those skilled in the art regarding the description of the present application.

[0060] like Figure 1 to Figure 3As shown, the normally closed electromagnetic pilot control valve provided in the embodiment of the present application includes a main valve unit 1 and an electromagnetic pilot valve unit 2, wherein the main valve unit 1 is provided with an inlet 11 and an outlet 12, the inlet 11 of the main valve unit 1 is used to pass the working medium, and its internal outlet end is connected to the inlet end of the electromagnetic pilot valve unit 2 through the medium inflow channel 3, the first outlet end of the electromagnetic pilot valve unit 2 is connected to the open cavity 1331 inside the main valve unit 1 through the first medium outflow channel 4, and the second outlet end of the electromagnetic pilot valve unit 2 is connected to the closed cavity 1332 inside the main valve unit 1 through the second medium outflow channel 5, and the open cavity 1331 inside the main valve unit 1 is relatively isolated from the closed cavity 1332 inside the main valve unit 1. The electromagnetic pilot valve unit 2 is provided with a first exhaust port 201 and a second exhaust port 202. The first exhaust port 201 is used to discharge the residual medium in the closed cavity 1332 inside the main valve unit 1, and the second exhaust port 202 is used to discharge the residual medium in the open cavity 1331 inside the main valve unit 1.

[0061] The electromagnetic pilot valve unit 2 opens or closes the communication channel between the electromagnetic pilot valve unit 2 and the main valve unit 1 through electromagnetic force, so that the working medium flowing in through the inlet 11 in the main valve unit 1 can drive the inlet 11 and the outlet 12 to connect or disconnect, so as to realize the opening or closing of the main valve unit 1.

[0062] The electromagnetic pilot control valve provided in the embodiment of the present application is a normally closed structure, which relies on a working medium to be opened or closed. It does not require the aid of high-pressure control gas and a control system when working, and can simplify the structure of the engine and reduce some weight.

[0063] In a specific embodiment, the main valve unit 1 includes a main housing 13, a main valve core 14, a main spring 15 and a piston 16. The main housing 13 is provided with an inlet chamber 131, an outlet chamber 132 and a control chamber 133 which are interconnected. A valve cover 134 is provided on one side of the main housing 13 where the control chamber is provided.

[0064] The inlet 11 is arranged at the inlet chamber 131, and the working medium can be introduced into the inlet chamber 131 through the inlet 11; the inlet chamber 131 is connected to the inlet end of the electromagnetic pilot valve unit 2 through the medium inflow channel 3. The outlet 12 is arranged at the outlet chamber 132, and the working medium can be discharged through the outlet 12. The control chamber 133 is connected to the first outlet end of the electromagnetic pilot valve unit 2 through the first medium outflow channel 4, and is connected to the second outlet end of the electromagnetic pilot valve unit 2 through the second medium outflow channel 5.

[0065] The main valve core 14 spans the inlet chamber 131, the outlet chamber 132 and the control chamber 133 along the length direction of the main shell 13, and the main valve core 14 forms a seal with the side wall of the main shell 13 at the connection between the inlet chamber 131 and the outlet chamber 132, which is used to control the connection and disconnection of the inlet chamber 131 and the outlet chamber 132; the main valve core 14 forms another seal with the side wall of the main shell 13 near the control chamber 133, which is used to isolate the outlet chamber 132 from the control chamber 133.

[0066] The main spring 15 is arranged in the inlet chamber 131, one end of the main spring 15 is connected to the side wall of the inlet chamber 131 along the length direction of the main shell 13, and the other end is connected to one end of the main valve core 14, and the other end of the main valve core 14 is connected to the piston 16. Under the push of the piston 16, the main valve core 14 can move along the length direction of the main shell 13.

[0067] The piston 16 is disposed in the control chamber 133. A first sealing ring 17 is sleeved on the outer side of the piston 16 along the circumference of the piston 16. The piston 16 and the first sealing ring 17 separate the control chamber 133 into an open chamber 1331 and a closed chamber 1332. The open chamber 1331 is disposed on a side of the piston 16 away from the outlet chamber 132, and the closed chamber 1332 is disposed on a side of the piston 16 close to the outlet chamber 132.

[0068] Specifically, the main valve core 14 includes a sealing head 141 and a push rod 142 connected to the sealing head 141. The sealing head 141 is in a bell-mouth shape. The sealing head 141 can block the connection between the inlet chamber 131 and the outlet chamber 132 to isolate the inlet chamber 131 from the outlet chamber 132. A second sealing ring 18 is sleeved on the side wall of the push rod 142 at the opposite end of the push rod 142 connected to the sealing head 141. The second sealing ring 18 is used to form a seal between the outlet chamber 132 and the closing chamber 1332 to isolate the outlet chamber 132 from the closing chamber 1332.

[0069] In a specific embodiment, the electromagnetic pilot valve unit 2 comprises a left valve cover 21, a right valve cover 22 and a pilot housing 23. The left valve cover 21 and the right valve cover 22 are fixedly connected to both ends of the pilot housing 23 in the length direction.

[0070] Along the length direction of the pilot housing 23, a first assembly hole is provided at one end of the pilot housing 23 connected to the left valve cover 21, and a second assembly hole is provided at one end of the pilot housing 23 connected to the right valve cover 22. The first assembly hole is connected to the second assembly hole through the through hole 231. The first assembly hole is connected to the first exhaust channel 232, and the first exhaust port 201 is provided at the end of the first exhaust channel 232. The second assembly hole is connected to the inlet chamber 131 through the medium inflow channel 3.

[0071] The first assembly hole is provided with an exhaust valve core 24. The second assembly hole is provided with a pilot valve, which includes a pilot valve core 25 and a first spring 26. A left spring hole is provided at one end of the pilot valve core 25 close to the right valve cover 22, and a right spring hole is provided at one end of the right valve cover 22 close to the pilot housing 23 corresponding to the left spring hole. When the right valve cover 22 is docked with the pilot housing 23, the left spring hole and the right spring hole form a first spring cavity 261, and the first spring 26 is provided in the first spring cavity 261. The first spring 26 can push the pilot valve core 25 to move in the second assembly hole.

[0072] A push rod 27 is provided in the through hole 231, one end of the push rod 27 is connected to the exhaust valve core 24, and the other end is connected to the pilot valve core 25. A gap is provided between the circumferential side wall of the push rod 27 and the inner wall of the pilot housing 23 where the through hole 231 is located. A first flow channel is provided inside the push rod 27 along the length direction thereof, and a vent hole is provided on the circumferential side wall of the push rod 27 for convenient ventilation. A second flow channel is provided inside the exhaust valve core 24, one end of the second flow channel is connected to the first flow channel inside the push rod 27, and the other end thereof is connected to the second medium outflow channel 5.

[0073] In addition, a first non-metallic part is arranged on the end surface of one end where the exhaust valve core 24 is connected to the push rod 27 and on the end surface of one end where the pilot valve core 25 is connected to the push rod 27. Correspondingly, a first metal sealing platform is arranged on the end surface where the pilot housing 23 where the first assembly hole is located contacts the exhaust valve core 24 and on the end surface where the pilot housing 23 where the second assembly hole is located contacts the pilot valve core 25. The first non-metallic part is used in combination with the first metal sealing platform to enhance the sealing between the first assembly hole and the through hole 231 and between the second assembly hole and the through hole 231.

[0074] Specifically, the first assembly hole includes a first guide hole and a first mounting hole, wherein the diameter of the first guide hole is smaller than the diameter of the first mounting hole. The portion of the exhaust valve core 24 located in the first guide hole is sleeved with a third sealing ring 241. The diameter of the exhaust valve core 24 is smaller than the diameter of the first mounting hole, so that a first left cavity 242 can be formed between the portion of the exhaust valve core 24 located in the first mounting hole and the inner wall of the pilot housing 23 where the first mounting hole is located. The provision of the third sealing ring 241 can enhance the sealing between the first left cavity 242 and the closing cavity 1332.

[0075] Specifically, the second assembly hole includes a second guide hole and a second mounting hole, wherein the diameter of the second guide hole is smaller than the diameter of the second mounting hole. The portion of the pilot valve core 25 located in the second guide hole is sleeved with a fourth sealing ring 251. The diameter of the pilot valve core 25 is smaller than the diameter of the second assembly hole, so that a first right cavity 252 can be formed between the portion of the pilot valve core 25 located in the second mounting hole and the inner wall of the pilot housing 23 where the second assembly hole is located. The provision of the fourth sealing ring 251 can enhance the sealing between the first right cavity 252 and the opening 1331.

[0076] A second right cavity 253 is formed between the end surface between the two left spring holes and the right valve cover 22 at one end of the pilot valve core 25 close to the right valve cover 22 .

[0077] In a specific embodiment, a third assembly hole is opened at the top of the pilot housing 23 along the height direction of the pilot housing 23. The third assembly hole is connected to the second assembly hole through the first connecting channel 2521. The second assembly hole is connected to the first medium outflow channel 4 through the second connecting channel 2522.

[0078] The third assembly hole is provided with a solenoid valve, wherein the solenoid valve comprises a solenoid housing 28 and a coil 281, a second spring 282 and a solenoid valve core 283 arranged in the solenoid housing 28. The solenoid housing 28 is provided with a second spring chamber 2821 and a valve core chamber 2831 which are interconnected, the second spring 282 is arranged in the second spring chamber 2821, the solenoid valve core 283 is arranged in the valve core chamber 2831, and the second spring 282 is used to push the solenoid valve core 283 to move in the valve core chamber 2831.

[0079] Specifically, a second exhaust channel 284 is disposed in the electromagnetic housing 28 , and the second exhaust port 202 is opened at the end of the second exhaust channel 284 . The second exhaust channel 284 can be communicated with the valve core chamber 2831 .

[0080] The second non-metallic part is disposed on both the upper and lower end surfaces of the electromagnetic valve core 283. Correspondingly, the end surface of the electromagnetic housing 28 in contact with the upper end surface of the electromagnetic valve core 283 and the end surface of the pilot housing 23 in contact with the lower end surface of the electromagnetic valve core 283 where the third assembly hole is located are both provided with a second metal sealing platform. The second non-metallic part is used in conjunction with the second metal sealing platform to enhance the sealing between the valve core cavity 2831 and the second exhaust channel 284 and between the valve core cavity 2831 and the first right cavity 252.

[0081] like Figure 2 As shown, a second flow channel is provided inside the exhaust valve core 24 , one end of the second flow channel is communicated with the first flow channel inside the push rod 27 , and the other end thereof is communicated with the second medium outflow channel 5 .

[0082] After the normally closed electromagnetic pilot control valve provided in the embodiment of the present application is assembled, under the action of the main spring 15, the main valve core moves toward the control chamber 133, and the head 141 in the main valve core is pressed against the sealing surface of the side wall of the main shell 13 at the connection between the inlet chamber 131 and the outlet chamber 132 to cut off the inlet chamber 131 and the working chamber 104, and the main valve unit 1 is in a closed state; the first spring 26 presses the pilot valve core 25 in the second assembly hole along the direction close to the left valve cover 21, and the second spring 282 presses the electromagnetic valve core 283 in the third assembly hole in the direction of the second assembly hole.

[0083] When the coil 281 is energized, the electromagnetic valve core 283 overcomes the elastic force of the second spring 282 under the action of the electromagnetic force and moves in the direction away from the second assembly hole. The second non-metallic part provided on the upper end surface of the electromagnetic valve core 283 is pressed against the second metal sealing platform provided on the electromagnetic housing 28, so that the valve core cavity 2831 is separated from the second exhaust port 202, and the first connecting channel 2521 is connected with the first medium outflow channel 4 through the valve core cavity 2831. The working medium in the inlet cavity 131 can enter the opening cavity 1331 through the medium inflow channel 3, the first right cavity 252, the first connecting channel 2521, the valve core cavity 2831 and the first medium outflow channel 4 in sequence, and can enter the second right cavity 253 through the medium inflow channel 3, the first right cavity 252, the first connecting channel 2521, the valve core cavity 2831, the first medium outflow channel 4 and the second connecting channel 2522 in sequence.

[0084] The working medium flowing into the opening 1331 pushes the piston to move toward the inlet chamber 131, and the main valve core 14 moves toward the inlet chamber 131 under the push of the piston 16 until the head 141 in the main valve core leaves the sealing surface of the side wall of the main shell 13 at the connection between the inlet chamber 131 and the outlet chamber 132. At this time, the inlet chamber 131 is connected with the outlet chamber 132, and the main valve unit 1 starts to work.

[0085] Under the action of the medium pressure in the second right cavity 253, the pilot valve core 25 is pressed in the second assembly hole along the direction close to the first assembly hole, and the pilot valve is in a closed state. At this time, the closing cavity 1332 is connected with the second medium outflow channel 5, the first left cavity 242, the first exhaust channel 232 and the first exhaust port 201, and the residual gas in the closing cavity 1332 is discharged into the atmosphere through the second medium outflow channel 5, the first left cavity 242, the first exhaust channel 232 and the first exhaust port 201 in turn, and there is no working pressure in the closing cavity 1332.

[0086] When the coil 281 is powered off, the solenoid valve core 283 moves toward the second assembly hole under the elastic force of the second spring 282, and the second non-metallic part arranged on the lower end surface of the solenoid valve core 283 is pressed against the second metal sealing platform arranged on the pilot housing 23 where the third assembly hole is located, so that the valve core cavity 2831 is separated from the first right cavity 252, the solenoid valve is closed, and the working medium in the inlet cavity 131 cannot enter the opening cavity 1331; at this time, the second non-metallic part arranged on the upper end surface of the solenoid valve core 283 is separated from the second metal sealing platform arranged on the electromagnetic housing 28, the valve core cavity 2831 is connected with the second exhaust port 202, and the residual working medium in the opening cavity 1331 and the second right cavity 253 is discharged to the atmosphere through the first medium outflow channel 4, the valve core cavity 2831, the gap channel on the side of the solenoid valve core 283, and the second exhaust channel 284 in turn, so as to achieve pressure relief.

[0087] Since there is an annular area between the cross-sectional area of ​​the fourth sealing ring 251 and the sealing area of ​​the pilot valve core 25, the working medium in the first right cavity 252 acts on the annular area to generate a force on the pilot valve core 25 pointing to the right valve cover 22, so that the pilot valve core 25 drives the exhaust valve core 24 to move toward the right valve cover 22 through the push rod 27 until the first non-metallic part provided on the exhaust valve core 24 fits with the first metal sealing platform provided on the pilot housing 23 where the first assembly hole is located and stops moving.

[0088] The presence of the third sealing ring 241 seals and separates the second medium outflow channel 5 from the first left cavity 242. The seal between the exhaust valve core 24 and the pilot housing 23 where the first assembly hole is located separates the first left cavity 242 from the first exhaust port 201. At this time, the second medium outflow channel 5 is connected with the first right cavity 252 and the closing cavity 1332. The working medium in the inlet cavity 131 flows into the closing cavity 1332 through the medium inflow channel 3, the first right cavity 252, the gap between the push rod 27 and the side wall of the pilot housing 23 where the through hole 231 is located, the vent hole on the side wall of the push rod 27 and the first flow channel inside the push rod 27, and the second medium outflow channel 5 in turn. Since there is no medium pressure in the open chamber 1331, the working medium forms a medium force in the closing chamber 1332 in the direction away from the inlet chamber 131. Under the combined action of the medium force in the closing chamber 1332 and the elastic force of the main spring, the piston and the main valve core move in the direction away from the inlet chamber 131 until the head 141 in the main valve core fits into the connection between the inlet chamber 131 and the outlet chamber 132 to isolate the inlet chamber 131 and the outlet chamber 132, and the main valve unit 1 is closed.

[0089] In the normally closed electromagnetic pilot control valve provided in the embodiment of the present application, after the solenoid valve in the electromagnetic pilot valve unit 2 is energized and opened, the working medium enters the open cavity 1331 through the inlet cavity 131, the medium inflow channel 3, the first right cavity 252, the first connecting channel 2521, the valve core cavity 2831 and the first medium outflow channel 4 in sequence; at the same time, the residual medium in the closed cavity 1332 is discharged into the atmosphere through the second medium outflow channel 5, the first left cavity 242, the first exhaust channel 232 and the first exhaust port 201, and there is no working pressure in the closed cavity 1332; the working medium in the open cavity 1331 controls the main valve unit 1 to open, and the normally closed electromagnetic pilot control valve is opened.

[0090] After the solenoid valve in the solenoid pilot valve unit 2 is powered off and closed, the working medium in the inlet chamber 131 cannot enter the open chamber 1331, and the remaining working medium in the open chamber 1331 and the second right chamber 253 is discharged into the atmosphere to achieve pressure relief; at this time, the working medium in the first right chamber 252 pushes the pilot valve core 25 to drive the exhaust valve core 24 to move in the direction of the second assembly hole, so that the first left chamber 242 is isolated from the first exhaust port 201, and the first right chamber 252 is connected to the closing chamber 1332 through the second medium outflow channel 5, and the working medium in the inlet chamber 131 flows into the closing chamber 1332. There is no medium pressure in the open chamber 1331, and the working medium in the closing chamber 1332 and the main spring elastic force jointly control the closing of the main valve unit 1, and the normally closed electromagnetic pilot control valve is closed.

[0091] The normally closed electromagnetic pilot control valve provided in the embodiment of the present application can realize the action requirements of controlling opening or closing by itself, thereby eliminating the dependence on the control system.

[0092] The above description is only an illustrative specific implementation manner of the present application. Without departing from the concept and principle of the present application, any equivalent changes and modifications made by any technician in the field should fall within the scope of protection of the present application.

Claims

1. A normally closed electromagnetic pilot control valve, It is characterized in that It comprises a main valve unit and an electromagnetic pilot valve unit, wherein the main valve unit is provided with an inlet and an outlet, wherein the inlet is used for introducing a working medium, and the outlet is used for discharging the working medium; The main valve unit is connected to the inlet end of the electromagnetic pilot valve unit through a medium inflow channel, the first outlet end of the electromagnetic pilot valve unit is connected to the open cavity inside the main valve unit through a first medium outflow channel, and the second outlet end of the electromagnetic pilot valve unit is connected to the closed cavity inside the main valve unit through a second medium outflow channel; the open cavity and the closed cavity are relatively isolated; The electromagnetic pilot valve unit is provided with a first exhaust port and a second exhaust port; the first exhaust port is used to exhaust the residual medium in the closed cavity, and the second exhaust port is used to exhaust the residual medium in the open cavity; The electromagnetic pilot valve unit comprises a left valve cover, a right valve cover and a pilot housing; the left valve cover and the right valve cover are fixedly connected to the two ends of the pilot housing respectively; a first assembly hole, a through hole, a second assembly hole and a third assembly hole are provided in the pilot housing, the first assembly hole is communicated with the second assembly hole through the through hole, and the second assembly hole is communicated with the third assembly hole through the first connecting channel; an exhaust valve core is provided in the first assembly hole, a push rod is provided in the through hole, a pilot valve is provided in the second assembly hole, and an electromagnetic valve is provided in the third assembly hole; the exhaust valve core is connected to the pilot valve through the push rod; After the solenoid valve is powered on and opened, the working medium enters the open cavity through the communication channel between the inlet cavity connected to the inlet and the pilot valve, the communication channel between the pilot valve and the solenoid valve, and the communication channel between the solenoid valve and the open cavity. The working medium in the open cavity controls the inlet cavity connected to the inlet to communicate with the outlet cavity connected to the outlet, and the residual medium in the closed cavity is discharged through the first exhaust port. After the solenoid valve is powered off and closed, the working medium enters the closing chamber through the connecting passage between the pilot valve and the push rod and the exhaust valve core and the connecting passage between the exhaust valve core and the closing chamber. The working medium in the closing chamber controls the separation between the inlet chamber and the outlet chamber. The working medium remaining in the open chamber is discharged through the connecting passage between the open chamber and the solenoid valve and the second exhaust port.

2. The normally closed electromagnetic pilot control valve according to claim 1, It is characterized in that The main valve unit comprises a main housing, a main valve core, a main spring and a piston; the main housing is provided with an inlet chamber, an outlet chamber and a control chamber which can communicate with each other; The inlet is arranged at the inlet chamber, and the inlet chamber is connected to the inlet end of the electromagnetic pilot valve unit through the medium inflow channel; the outlet is arranged at the outlet chamber, and the control chamber is connected to the first outlet end of the electromagnetic pilot valve unit through the first medium outflow channel, and is connected to the second outlet end of the electromagnetic pilot valve unit through the second medium outflow channel; The main valve core spans the inlet chamber, the outlet chamber and the control chamber along the length direction of the main housing, and the main valve core forms a seal with the side wall of the main housing at the connection between the inlet chamber and the outlet chamber, which is used to control the opening and closing of the inlet chamber and the outlet chamber; the main valve core forms another seal with the side wall of the main housing near the control chamber, which is used to control the opening and closing of the outlet chamber and the control chamber; The main spring is arranged in the inlet chamber, one end of the main spring is connected to the side wall of the inlet chamber along the length direction of the main housing, the other end of the main spring is connected to one end of the main valve core, the other end of the main valve core is connected to the piston, and the main valve core can move along the length direction of the main housing under the push of the piston; The piston is arranged in the control chamber, and a first sealing ring is sleeved on the outer side of the piston along the circumference of the piston. The piston and the first sealing ring separate the control chamber into an open chamber and a closed chamber; the open chamber is arranged on a side of the piston away from the outlet chamber, and the closed chamber is arranged on a side of the piston close to the outlet chamber.

3. The normally closed electromagnetic pilot control valve according to claim 2, It is characterized in that The main valve core comprises a sealing head and a push rod connected to the sealing head, and the sealing head is used to seal the connection between the inlet cavity and the outlet cavity.

4. The normally closed electromagnetic pilot control valve according to claim 3, It is characterized in that A second sealing ring is sleeved on the side wall of the push rod at the end opposite to the end where the push rod is connected to the sealing head. The second sealing ring is used to form a seal between the outlet cavity and the closing cavity to isolate the outlet cavity and the closing cavity.

5. The normally closed electromagnetic pilot control valve according to claim 2, It is characterized in that Located in the pilot housing, the first assembly hole is arranged at one end of the pilot housing connected to the left valve cover, and the second assembly hole is arranged at one end of the pilot housing connected to the right valve cover; the second assembly hole is connected to the inlet chamber through the medium inflow channel; The third assembly hole is arranged at the top of the pilot housing along a direction perpendicular to the direction of the pilot housing where the first assembly hole and the second assembly hole are located.

6. The normally closed electromagnetic pilot control valve according to claim 2, It is characterized in that The pilot valve includes a pilot valve core and a first spring. A left spring hole is provided at one end of the pilot valve core close to the right valve cover. A right spring hole is provided at one end of the right valve cover close to the pilot housing corresponding to the left spring hole. When the right valve cover is docked with the pilot housing, the left spring hole and the right spring hole form a first spring cavity. The first spring is provided in the first spring cavity. The first spring is used to apply a force to the pilot valve core toward the left valve cover so that the pilot valve core is pressed tightly in the second assembly hole.

7. The normally closed electromagnetic pilot control valve according to claim 2, It is characterized in that The solenoid valve includes an electromagnetic housing and a coil, a second spring and a solenoid valve core arranged in the electromagnetic housing; a second spring chamber and a valve core chamber that are interconnected are arranged inside the electromagnetic housing, the second spring is arranged in the second spring chamber, and the solenoid valve core is arranged in the valve core chamber, and the second spring is used to apply a force to the solenoid valve core so that it moves toward the direction close to the second assembly hole when the coil is powered off.

8. The normally closed electromagnetic pilot control valve according to claim 1, It is characterized in that The first assembly hole includes a first guide hole and a first mounting hole, and the diameter of the first guide hole is smaller than the diameter of the first mounting hole; A third sealing ring is sleeved on the part of the exhaust valve core located in the first guide hole; a first left cavity is formed between the part of the exhaust valve core located in the first mounting hole and the inner wall of the pilot housing where the first mounting hole is located, and the third sealing ring is used to enhance the sealing between the first left cavity and the closing cavity.

9. The normally closed electromagnetic pilot control valve according to claim 6, It is characterized in that The second assembly hole includes a second guide hole and a second mounting hole, the diameter of the second guide hole is smaller than the diameter of the second mounting hole; the part of the pilot valve core located in the second guide hole is sleeved with a fourth sealing ring; a first right cavity is formed between the part of the pilot valve core located in the second mounting hole and the inner wall of the pilot housing where the second assembly hole is located; the fourth sealing ring is used to enhance the sealing between the first right cavity and the open cavity.

10. The normally closed electromagnetic pilot control valve according to claim 1, It is characterized in that A first flow channel is disposed inside the push rod, and a second flow channel is disposed inside the exhaust valve core. One end of the second flow channel is communicated with the first flow channel, and the other end of the second flow channel is communicated with the second medium outflow channel.

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