A multi-source dual-mode driving valve structure and method based on a multi-path pilot valve group

Abstract

The present application belongs to the technical field of valve equipment, and particularly relates to a multi-source bimodal driving valve structure and method based on a multi-way pilot valve group. The multi-source bimodal driving valve structure of the multi-way pilot valve group comprises a valve body, a piston type movement assembly is arranged in the internal cavity of the valve body, and the piston type movement assembly is communicated with the multi-way pilot valve group arranged outside the valve body through a through hole arranged in the side wall of the valve body. The present application has the following beneficial effects: 1) the present application uses the multi-way pilot valve group to drive the multi-source bimodal valve, replaces the opening and closing force applied to the valve core by the traditional energy driving device, fully utilizes the pipeline system resources, reduces energy consumption, and can be applied to multiple types of valves such as stop valves, gate valves, ball valves and butterfly valves. 2) the multi-source bimodal driving valve of the present application has a compact appearance, saves equipment space environment, is modularly designed, is convenient to maintain, and has low overall cost. 3) the present application has high automation control, and is beneficial to the digitalization and intelligentization development of the valve.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of valve equipment, and particularly relates to a multi-source bimodal driving valve structure and method based on a multi-way pilot valve group. BACKGROUND

[0002] Valves are control components in fluid conveying systems, and have functions such as opening and closing pipelines, controlling flow direction, adjusting and controlling parameters of conveying media, etc. The structure of valve driving devices can be divided into manual, electric, pneumatic, hydraulic, linkage and other forms. At present, the valve driven by energy has a large size, a single energy driving mode and requirements for the space of equipment, and has limitations in aspects such as manufacturing cost, automatic control and response speed.

[0003] Therefore, it is of great significance to explore and develop a valve with a multi-source driving mode, a simple structure, a small occupied space, easy automatic control and easy maintenance. SUMMARY

[0004] The present application aims at the defects of the prior art, and provides a multi-source bimodal driving valve structure and method based on a multi-way pilot valve group. The method can select external source media or self media in a pipeline system through the multi-way pilot valve group, and then drive the opening and closing of the valve by using the pilot valve group to control the pressure difference force of the upper and lower chambers, so that the driving module is designed, the pipeline system resources can be utilized, the energy consumption is reduced, and the external source driving can be used for operation and maintenance.

[0005] The specific technical solutions adopted by the present application are as follows:

[0006] A multi-source bimodal driving valve structure of a multi-way pilot valve group, comprising a valve body, a piston type movement assembly is arranged in the internal cavity of the valve body, and the piston type movement assembly is communicated with a multi-way pilot valve group arranged outside the valve body through a through hole arranged in the side wall of the valve body.

[0007] The multi-source bimodal driving valve structure of the multi-way pilot valve group as described above, wherein the bottom end of the piston type movement assembly is provided with a valve flap.

[0008] The multi-source bimodal driving valve structure of the multi-way pilot valve group as described above, wherein the side wall of the valve body is provided with two through holes arranged above and below, an upper cavity through piece and a lower cavity through piece are arranged in the two through holes respectively, and the side wall of the piston type movement assembly is provided with through holes corresponding to the upper cavity through piece and the lower cavity through piece.

[0009] The multi-source bimodal driving valve structure of the multi-way pilot valve group as described above, wherein the piston type movement assembly comprises a transmission rod assembly, a piston cylinder assembly and a cylinder cover assembly; the cylinder cover assembly is connected with the piston cylinder assembly to form a piston chamber; the transmission rod assembly is a cross stepped type and is arranged in the chamber to form upper and lower chambers.

[0010] The multi-source bimodal drive valve structure of a multi-way pilot valve group as described above, wherein the cylinder cover assembly comprises a cylinder cover and an upper chamber guide sleeve, the upper chamber guide sleeve is fixed on the cylinder cover, the piston cylinder assembly comprises a piston cylinder and a lower chamber guide sleeve, the lower chamber guide sleeve is installed at the bottom of the piston cylinder, the transmission rod assembly comprises a transmission rod, an elastic sealing element and a throttle screw; the elastic sealing element is arranged in the maximum outer circle of the transmission rod and is in elastic contact with the inner wall of the piston cylinder to form a reciprocating dynamic seal.

[0011] The multi-source bimodal drive valve structure of a multi-way pilot valve group as described above, wherein the multi-way pilot valve group is a multi-channel combined valve structure, and the multi-way pilot valve group is connected with the upper and lower chambers through the medium passage hole provided by the piston cylinder.

[0012] The multi-source bimodal drive valve structure of a multi-way pilot valve group as described above, wherein the piston cylinder assembly, the cylinder cover assembly and the transmission rod assembly jointly constitute a piston type motion assembly which can be built-in or built-out of the valve.

[0013] The multi-source bimodal drive valve structure of a multi-way pilot valve group as described above, wherein the elastic sealing element is arranged in the maximum outer circle of the transmission rod and is in elastic contact with the piston cylinder to form a dynamic seal and establish the seal between the upper chamber and the lower chamber of the piston chamber.

[0014] The multi-source bimodal drive valve structure of a multi-way pilot valve group as described above, wherein part of the inner hole section of the upper chamber guide sleeve is used for guiding the transmission rod assembly, and the other part of the upper chamber guide sleeve is also used for limiting the movement stroke of the transmission rod assembly; part of the inner hole section of the lower chamber guide sleeve is used for guiding the transmission rod assembly and also used for limiting the movement stroke of the transmission rod assembly.

[0015] The multi-source bimodal drive valve structure of a multi-way pilot valve group as described above, wherein the medium passage hole is divided into an upper chamber pilot passage hole and a lower chamber pilot passage hole, the upper chamber pilot passage hole is correspondingly arranged at the upper half of the upper chamber guide sleeve to avoid the blockage of the flow passage hole when the transmission rod assembly moves up and down; the lower chamber pilot passage hole is correspondingly arranged at the lower half of the lower chamber guide sleeve to avoid the blockage of the flow passage hole when the transmission rod assembly moves up and down.

[0016] The multi-source bimodal drive valve structure of a multi-way pilot valve group as described above, wherein the throttle screw is provided with a throttle hole for balancing the medium pressure in the upper and lower chambers and facilitating the adjustment of the time for establishing the pressure difference.

[0017] The multi-source bimodal drive valve structure of a multi-way pilot valve group as described above, wherein the axes of the lower chamber guide sleeve, the transmission rod and the upper chamber guide sleeve coincide.

[0018] The multi-source double-mode driving valve structure of a multi-way pilot valve group as described above, wherein the transmission rod assembly can be directly connected to the opening and closing element of a straight stroke type valve, such as a stop valve or a gate valve.

[0019] The multi-source double-mode driving valve structure of a multi-way pilot valve group as described above, wherein the transmission rod assembly is additionally provided with a reversing mechanism and can be applied to valves with partial rotation opening and closing actions, such as ball valves or butterfly valves.

[0020] The multi-source double-mode driving valve structure of a multi-way pilot valve group as described above, wherein the multi-way pilot valve group has double-mode driving control valve opening and closing elements with external source driving + medium self-driving, and the driving source can be liquid, gas, steam or other pressurized fluid with certain cleanliness.

[0021] The multi-source double-mode driving valve method of a multi-way pilot valve group, wherein the following contents are included,

[0022] The multi-way pilot valve group can be switched to external source driving valve opening and closing through the control valve (K2), and can be switched to medium self-driving mode driving valve opening and closing through the control valve (K1),

[0023] Driving mode 1: when the valve adopts the medium self-driving mode, the initial state of each control valve of the multi-way pilot valve group is that the control valve (K1) is opened, the control valve (K2) is closed, the control valve (K3) is opened, the control valve (K4) is opened, the control valve (K5) is closed, the control valve (K6) is closed, the control valve (K7) is closed, and the control valve (K8) is closed, that is, the medium in the valve pipeline system enters the upper and lower chambers of the valve through the control valve (K1), the control valve (K3) and the control valve (K4), respectively, and the upper and lower chambers are in a balanced state through the throttle hole on the transmission rod (311),

[0024] When the valve is opened, the control valve (K4) of the multi-way pilot valve group is closed, the control valve (K6) is opened, and the control valve (K7) is opened, that is, the medium in the upper chamber of the valve is discharged to the upstream system of the valve pipeline, the pressure in the upper chamber is reduced, and a certain pressure difference is formed with the lower chamber of the valve, when the pressure difference overcomes a series of resistances such as the gravity of the piston and the friction force, the valve core moves upward, and the valve is opened,

[0025] When the valve is closed, the control valve (K6) of the multi-way pilot valve group is closed, the control valve (K4) is opened, then the control valve (K3) is closed, and the control valve (K5) is opened, that is, the medium in the lower chamber of the valve is discharged to the upstream system of the valve pipeline, the pressure in the lower chamber is reduced, and a certain pressure difference is gradually formed with the upper chamber of the valve, when the pressure difference and the gravity of the piston overcome a series of resistances such as the friction force, the valve core moves downward, and the valve is closed,

[0026] Drive mode 2: when the valve adopts external source drive mode, the initial state of each control valve of the multi-way pilot valve group is that the control valve (K1) is closed, the control valve (K2) is opened, the control valve (K3) is opened, the control valve (K4) is opened, the control valve (K5) is closed, the control valve (K6) is closed, the control valve (K7) is closed, and the control valve (K8) is closed, that is, the medium in the valve pipeline system enters the upper and lower chambers of the valve through the control valve (K2), the control valve (K3) and the control valve (K4) respectively, and the upper and lower chambers are balanced through the throttle hole on the transmission rod,

[0027] When the valve is opened, the control valve (K4) of the multi-way pilot valve group (5) is closed, the control valve (K6) is opened, and the control valve (K8) is opened, that is, the medium in the upper chamber of the valve is discharged into the upstream system of the external source, the pressure of the upper chamber is reduced, and a certain pressure difference is formed with the lower chamber of the valve, when the pressure difference overcomes the total resistance of the piston gravity, friction and other series of resistances, the valve core moves upward, and the valve is opened.

[0028] When the valve is closed, the control valve (K6) of the multi-way pilot valve group is closed first, the control valve (K4) is opened, then the control valve (K3) is closed, and the control valve (K5) is opened, that is, the medium in the lower chamber of the valve is discharged into the upstream system of the external source, the pressure of the lower chamber is reduced, and a certain pressure difference is gradually formed with the upper chamber of the valve, when the pressure difference and the total resistance of the piston gravity overcome the total resistance of the series of resistances such as friction, the valve core moves downward, and the valve is closed.

[0029] The present application has the following beneficial effects relative to the prior art:

[0030] 1) The multi-source double-mode drive valve of the present application is driven by a multi-way pilot valve group, which replaces the opening and closing force applied to the valve core by the traditional energy driving device, fully utilizes the pipeline system resources, reduces energy consumption, and can be applied to multiple types of valves such as stop valves, gate valves, ball valves and butterfly valves.

[0031] 2) The multi-source double-mode drive valve of the present application is compact in appearance, saves equipment space environment, is modular in design, easy to maintain, and low in overall cost.

[0032] 3) The present application has high automation control, which is beneficial to the digitalization and intelligentization development of the valve. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 is the pipeline medium self-driving mode drive valve logic diagram of the multi-way pilot valve group of the present application;

[0034] Figure 2 is the external source mode drive valve logic diagram of the multi-way pilot valve group of the present application;

[0035] Figure 3This is a structural example diagram of the multi-source dual-mode driven valve of the multi-port pilot valve group of the present invention (taking a shut-off valve with an internal valve body as an example);

[0036] Figure 4 This is a structural example diagram of the piston-type motion component of the multi-source dual-mode driven shut-off valve of the present invention, which is built into the valve body.

[0037] In the diagram: 1. Valve body; 2. Valve disc; 3. Piston motion assembly; 31. Drive rod assembly; 311. Drive rod; 312. Elastic sealing element; 313. Throttle screw; 32. Piston cylinder assembly; 321. Piston cylinder; 322. Lower chamber guide sleeve; 33. Cylinder head assembly; 331. Cylinder head; 332. Upper chamber guide sleeve; 4. Upper chamber through-hole; 5. Multi-port pilot valve assembly; 6. Lower chamber through-hole. Detailed Implementation

[0038] The present invention will be further described and illustrated below with reference to the accompanying drawings and specific embodiments. The technical features of each embodiment of the present invention can be combined accordingly, provided that there is no mutual conflict.

[0039] like Figure 1 The diagram shown is a specific structural example of a multi-source dual-mode driven shut-off valve based on a multi-port pilot valve assembly provided by the present invention. It mainly includes a valve body 1, a valve disc 2, a transmission rod 311, an elastic sealing element 312, a throttle screw 313, a piston cylinder 321, a lower chamber guide sleeve 322, a cylinder head 331, an upper chamber guide sleeve 332, an upper chamber through-piece 4, a multi-port pilot valve assembly 5, and a lower chamber through-piece 6. The transmission rod 311, elastic sealing element 312, and throttle screw 313 constitute the transmission rod assembly 31; the piston cylinder 321 and lower chamber guide sleeve 322 constitute the piston cylinder assembly 32; the cylinder head 331 and upper chamber guide sleeve 332 constitute the cylinder head assembly 33; and the transmission rod assembly 31, piston cylinder assembly 32, and cylinder head assembly 33 constitute the piston-type motion assembly 3. The structure of each component and the connection relationships between them will be described in detail below.

[0040] The inlet and outlet of valve body 1 are connected to the upstream and downstream of the pipeline system, respectively. The upper flange of valve body 1 is coaxial with the valve seat sealing channel of valve body 1. The piston-type moving assembly 3 is placed inside valve body 1 and fixed at the upper flange of valve body 1. It is connected by bolts to form a boundary seal.

[0041] The piston-type motion assembly 3 includes a transmission rod assembly 31, a piston cylinder assembly 32, and a cylinder head assembly 33; the piston-type motion assembly 3 is entirely built into the valve body 1; one end of the transmission rod assembly 31 in the piston-type motion assembly 3 is connected to the valve disc 2, and the valve disc 2 and the piston-type motion assembly 3 can be completely separated for easy disassembly and maintenance.

[0042] The cylinder cover 331 in the cylinder cover assembly 33 is of double flange type, one end is connected to the middle flange of the valve body 1 by bolts to form a middle cavity closed pressure boundary, and the other end is connected to the opening of the piston cylinder 321 of the piston cylinder assembly 32 by bolts, and the inside forms a closed chamber; the transmission rod assembly 31 is of cross stepped type, which is placed in the closed chamber and divides the closed chamber into upper and lower chambers. The upper chamber guide sleeve 332 provided on the cylinder cover 331 is used for movement guide of the transmission rod assembly 31, and the other upper chamber guide sleeve 332 is also used for movement stroke limiting of the transmission rod assembly 31. The upper chamber guide sleeve 332 is provided with a passage hole for balancing the internal medium pressure, and is connected to the cylinder cover 331 by bolts, which is convenient for maintenance of the upper chamber guide sleeve 332 and reduces the cost of spare parts.

[0043] The piston cylinder 321 in the piston cylinder assembly 32 is of open cylinder type, and the lower chamber guide sleeve 322 provided on the piston cylinder 321 is used for movement guide of the transmission rod assembly 31, and the other lower chamber guide sleeve 322 is also used for movement stroke limiting of the transmission rod assembly 31. The lower chamber guide sleeve 322 is connected to the piston cylinder 321 by bolts, which is convenient for maintenance of the lower chamber guide sleeve 322 and reduces the cost of spare parts.

[0044] The transmission rod assembly 31 includes a transmission rod 311, an elastic sealing element 312 and a throttle screw 313. The elastic sealing element 312 is placed in the piston ring groove of the transmission rod 311 and is in elastic contact with the piston cylinder 321, which can form a certain seal for the upper and lower chambers and is the basis for establishing pressure difference between the upper and lower chambers. The throttle screw 313 is installed in the maximum outer circular axial direction of the transmission rod 311 by threads, the center of the throttle screw 313 is provided with a throttle hole for balancing the medium pressure of the upper and lower chambers, and the throttle hole diameter size can be replaced through threaded installation, so as to adjust the action time of the transmission rod.

[0045] The lower end of the transmission rod 311 is connected to the valve disc 2 by threads, the valve disc 2 is the opening and closing part of the valve, and can form a sealing pair with the valve seat of the valve body 1. The transmission rod assembly 31 and the valve disc 2 form a movement piston, which can move up and down based on the pressure difference change of the upper and lower chambers.

[0046] The piston cylinder 321 corresponding to the upper and lower chambers is provided with a medium passage hole, and the valve body 1 is also provided with a passage hole at the corresponding position; the upper chamber through member 4 and the lower chamber through member 6 are respectively placed in the connecting holes of the upper and lower chambers of the valve body 1 and the piston cylinder 321, and form the closed nature of the chamber medium passage.

[0047] The multi-way pilot valve group 5 is bolted to the valve body 1 to form a certain boundary seal; each channel of the multi-way pilot valve group 5 is arranged with a control valve for controlling the flow direction of the medium; the channel A of the multi-way pilot valve group 5 is connected to the valve pipeline inlet, i.e. the channel A is the interface of the self-medium driving source; the channel B of the multi-way pilot valve group 5 is connected to the external source system, i.e. the channel B is the interface of the external medium driving source; the channel S of the multi-way pilot valve group 5 is connected to the upper chamber of the valve, and the channel S of the multi-way pilot valve group 5 is connected to the upper chamber through hole to form a medium channel of the upper chamber of the valve; the channel X of the multi-way pilot valve group 5 is connected to the lower chamber through hole to form a medium channel of the lower chamber of the valve; the channel F of the multi-way pilot valve group 5 is connected to the upstream system of the valve pipeline, and the channel W of the multi-way pilot valve group 5 is connected to the upstream system of the external source.

[0048] The control valve K1 of the multi-way pilot valve group 5 controls the flow of the valve pipeline medium in the multi-way pilot valve group 5, and the one-way valve D1 controls the flow direction of the medium; the control valve K2 controls the flow of the external source medium in the multi-way pilot valve group 5, and the one-way valve D2 controls the flow direction of the medium; the control valve K3 and the control valve K5 of the multi-way pilot valve group 5 control the flow of the lower chamber medium, wherein the control valve K3 functions as a charging valve, and the control valve K5 functions as a pressure relief valve; the control valve K4 and the control valve K6 of the multi-way pilot valve group 5 control the flow of the upper chamber medium, wherein the control valve K4 functions as a charging valve, and the control valve K6 functions as a pressure relief valve; the control valve K7 of the multi-way pilot valve group 5 controls the flow of the valve upper and lower chamber medium discharged to the upstream system of the valve pipeline; the control valve K8 of the multi-way pilot valve group 5 controls the flow of the valve upper and lower chamber medium discharged to the upstream system of the external source.

[0049] The channel A, the control valve K1, the one-way valve D1, the control valve K3, the control valve K5, the channel X, the control valve K4, the control valve K6, the channel S, the control valve K7 and the channel F of the multi-way pilot valve group 5 constitute a valve self-driving module in a medium self-driving mode; the channel B, the control valve K2, the one-way valve D2, the control valve K3, the control valve K5, the channel X, the control valve K4, the control valve K6, the channel S, the control valve K8 and the channel W of the multi-way pilot valve group 5 constitute a valve opening and closing control module in an external source driving mode.

[0050] The method for driving the valve to open and close by the multi-source dual-mode driving valve opening and closing device is as follows:

[0051] Driving mode 1: when the valve adopts the medium self-driving mode, the initial state of each control valve of the multi-way pilot valve group 5 is that the control valve K1 is opened, the control valve K2 is closed, the control valve K3 is opened, the control valve K4 is opened, the control valve K5 is closed, the control valve K6 is closed, the control valve K7 is closed, and the control valve K8 is closed, i.e. the medium in the valve pipeline system enters the upper and lower chambers of the valve through the control valve K1, the control valve K3 and the control valve K4 respectively, and the upper and lower chambers are balanced through the throttle hole on the transmission rod 311.

[0052] When the valve is opened, the control valve K4 of the multi-way pilot valve group 5 is closed, the control valve K6 is opened and the control valve K7 is opened, i.e. the medium in the upper chamber of the valve is discharged into the system upstream of the valve line, the pressure in the upper chamber is reduced, and a certain pressure difference is formed with the lower chamber of the valve. When the pressure difference overcomes the sum of the piston gravity, friction force and other resistances, the valve core moves upward, and the valve is opened.

[0053] When the valve is closed, the control valve K6 of the multi-way pilot valve group 5 is closed first, the control valve K4 is opened, and then the control valve K3 is closed and the control valve K5 is opened, i.e. the medium in the lower chamber of the valve is discharged into the system upstream of the valve line, the pressure in the lower chamber is reduced, and a certain pressure difference is gradually formed with the upper chamber of the valve. When the sum of the pressure difference and the piston gravity overcomes the sum of the friction force and other resistances, the valve core moves downward, and the valve is closed.

[0054] Drive mode 2: When the valve adopts the external source drive mode, the initial state of each control valve of the multi-way pilot valve group 5 is that the control valve K1 is closed, the control valve K2 is opened, the control valve K3 is opened, the control valve K4 is opened, the control valve K5 is closed, the control valve K6 is closed, the control valve K7 is closed, and the control valve K8 is closed, i.e. the medium in the valve line system enters the upper and lower chambers of the valve through the control valves K2, K3 and K4, and the upper and lower chambers are balanced through the throttle hole on the transmission rod 311.

[0055] When the valve is opened, the control valve K4 of the multi-way pilot valve group 5 is closed, the control valve K6 is opened and the control valve K8 is opened, i.e. the medium in the upper chamber of the valve is discharged into the system upstream of the external source, the pressure in the upper chamber is reduced, and a certain pressure difference is formed with the lower chamber of the valve. When the pressure difference overcomes the sum of the piston gravity, friction force and other resistances, the valve core moves upward, and the valve is opened.

[0056] When the valve is closed, the control valve K6 of the multi-way pilot valve group 5 is closed first, the control valve K4 is opened, and then the control valve K3 is closed and the control valve K5 is opened, i.e. the medium in the lower chamber of the valve is discharged into the system upstream of the external source, the pressure in the lower chamber is reduced, and a certain pressure difference is gradually formed with the upper chamber of the valve. When the sum of the pressure difference and the piston gravity overcomes the sum of the friction force and other resistances, the valve core moves downward, and the valve is closed.

[0057] The above-described embodiment is a specific embodiment of the present application, but is not intended to limit the present application. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application, and the technical solutions obtained by equivalent replacement or equivalent transformation also fall within the protection scope of the present application.

Claims

1. A method for multi-source dual-mode driven valves in a multi-port pilot valve assembly, characterized in that: Includes the following: The multi-way pilot valve assembly (5) can be switched to external power supply to drive the valve opening and closing via control valve K2, and can also be switched to media self-driven mode to drive the valve opening and closing via control valve K1. Drive mode 1: When the valve adopts the medium self-drive mode, the initial state of each control valve in its multi-way pilot valve group (5) is as follows: control valve K1 is open, control valve K2 is closed, control valve K3 is open, control valve K4 is open, control valve K5 is closed, control valve K6 is closed, control valve K7 is closed, and control valve K8 is closed. That is, the medium in the valve pipeline system enters the upper and lower chambers of the valve through control valves K1, K3, and K4 respectively, and the upper and lower chambers are in a balanced state through the throttling orifice on the transmission rod (311). When the valve opens, the control valve K4 of the multi-way pilot valve group (5) is closed, the control valve K6 is opened, and the control valve K7 is opened. That is, the medium in the upper chamber of the valve is discharged into the upstream system of the valve pipeline. The pressure in the upper chamber decreases, forming a certain pressure difference with the lower chamber of the valve. When the pressure difference overcomes the sum of a series of resistances, including piston gravity and friction, the valve core moves upward and the valve opens. When the valve is closed, first close the control valve K6 and open the control valve K4 of the multi-way pilot valve group (5), then close the control valve K3 and open the control valve K5. That is, the medium in the lower chamber of the valve is discharged into the upstream system of the valve pipeline. The pressure in the lower chamber decreases and gradually forms a certain pressure difference with the upper chamber of the valve. When the sum of the pressure difference and the weight of the piston overcomes the sum of a series of resistances including friction, the valve core moves downward and the valve closes. Drive mode 2: When the valve adopts the external power supply drive mode, the initial state of each control valve in its multi-way pilot valve group (5) is as follows: control valve K1 is closed, control valve K2 is open, control valve K3 is open, control valve K4 is open, control valve K5 is closed, control valve K6 is closed, control valve K7 is closed, and control valve K8 is closed. That is, the medium in the valve pipeline system enters the upper and lower chambers of the valve through control valves K2, K3, and K4 respectively, and the upper and lower chambers are in a balanced state through the throttling orifice on the transmission rod (311). When the valve is opened, the control valve K4 of the multi-way pilot valve group (5) is closed, the control valve K6 is opened, and the control valve K8 is opened. That is, the medium in the upper chamber of the valve is discharged into the upstream system of the external power supply. The pressure in the upper chamber decreases, forming a certain pressure difference with the lower chamber of the valve. When the pressure difference overcomes the sum of a series of resistances, including piston gravity and friction, the valve core moves upward and the valve opens. When the valve is closed, the control valve K6 of the multi-way pilot valve group (5) is closed and the control valve K4 is opened first. Then the control valve K3 is closed and the control valve K5 is opened. That is, the medium in the lower chamber of the valve is discharged to the upstream system of the external power supply. The pressure in the lower chamber decreases and gradually forms a certain pressure difference with the upper chamber of the valve. When the sum of the pressure difference and the weight of the piston overcomes the sum of a series of resistances including friction, the valve core moves downward and the valve is closed.

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