Two-position three-way two-stage gas valve

Abstract

The invention provides a two-position three-way two-stage gas valve. The two-position three-way two-stage gas valve comprises a main valve body, a pilot electromagnetic valve, a main valve element and a lining. The main valve body is provided with two gas main channels and a pilot gas inlet channel, the two ends of the main valve body are provided with the bushings and the pilot electromagnetic valves respectively, the two gas inlet channels of the pilot electromagnetic valves are reserved in the main valve body, the main valve element is installed in the main valve body, and two cavities are formed between the two ends of the main valve element and the corresponding bushings. When the pilot electromagnetic valves at the two ends are not powered on, under the action of the damping holes, the two cavities are in a low-pressure state, the main valve element is in a random state, and pressure relief openings of the two pilot electromagnetic valves exhaust gas normally; when the pilot electromagnetic valve at one end is powered on, the lining at the end is tightly attached to the valve element of the pilot electromagnetic valve, the pressure of the cavity at the end is consistent with the pressure of the inlet and higher than the pressure in the cavity at the other end, and the main valve element moves under the action of the pressure difference of the cavities to open the main fuel gas channel at the side. The pilot electromagnetic valves at the two ends are alternately powered on and powered off, reciprocating motion of the main valve element is achieved, and then the purpose of gas main channel switching is achieved.

Description

Technical Field

[0001] The present invention relates to a two-position three-way two-stage gas valve used in a high-temperature gas environment, which can be used in the field of direct force control and the field of gas turbine power generation air intake control, and belongs to the field of special valve products. Background Art

[0002] At present, in the field of direct force control and gas turbine power generation air intake control, domestic gas valves generally adopt electromagnetic direct drive structure, such as a dual voice coil motor direct drive two-position three-way high-temperature reversing valve, patent authorization number: ZL201911089246.X, which uses a voice coil motor to control the movement of the gas valve core to realize the opening and closing of the valve; in addition, "Research on High Temperature and High Pressure Technology of Small Gas Valves" (Science and Technology Innovation and Application 2012 No. 25, September 2012) also uses a linear motor to control the movement of the valve core. The above two valves are both single-stage structures. The large driving force required will cause the electromagnetic drive device structure to be very heavy. At the same time, due to the increase in power consumption, the coil heats up more seriously.

[0003] The article "Analysis of the Internal Flow Field in the Switching State of Solid Gas Valve" (Aviation Weapon 2014, No. 3, June 2014) mentioned a two-stage floating lift gas valve, which uses the pressure of the pilot chamber to control and then change the force direction of the main valve core to realize the opening and closing of the valve. The use of this valve has certain limitations. It cannot be used alone in solid gas media, and multiple valves must be used to ensure that there are always valves in the open state at different times. In addition, the valve needs to be used together with an integrated nozzle to ensure the force change of the main valve core. When there is throttling in the downstream, the force condition of the main valve core will change, causing the valve to be unable to open and close normally. Summary of the invention

[0004] The technical problem solved by the present invention is to overcome the deficiencies of the prior art and provide a two-stage gas valve with large main valve core control force, low coil heating, good safety and high reliability.

[0005] The technical solution of the present invention is: a two-position three-way two-stage gas valve, comprising a main valve body, a pilot solenoid valve, a main valve core, and a bushing;

[0006] Two main gas channels and a pilot air intake channel are arranged on the main valve body, sleeves and pilot solenoid valves are respectively installed at two ends of the main valve body, and air intake channels for two pilot solenoid valves are reserved on the main valve body. The main valve core is installed in the main valve body, and two cavities are formed between the two ends of the main valve core and the corresponding sleeves. When the pilot solenoid valves at both ends are not energized, the two cavities are both in a low-pressure state, the main valve core is in a random state, and the pressure relief ports of the two pilot solenoid valves are exhausted normally; when the pilot solenoid valve at one end is energized, the sleeve at this end fits tightly with the valve core of the pilot solenoid valve, the pressure in the cavity at this end is consistent with the inlet pressure and is higher than the pressure in the cavity at the other end, and the main valve core moves under the action of the cavity pressure difference to open the main gas channel on this side; the pilot solenoid valves at both ends are alternately powered on and off to realize the reciprocating motion of the main valve core, thereby achieving the purpose of switching the main gas channel.

[0007] Preferably, a gap dynamic seal is used between the main valve core and the bushing.

[0008] Preferably, the main valve core and the bushing are made of the same material and have the same expansion coefficient.

[0009] Preferably, the main valve core is provided with a pressure equalizing groove, which is arranged in the clearance matching area between the main valve core and the bushing and is a plurality of annular grooves, so as to avoid the main valve core and the bushing from being stuck to the greatest extent.

[0010] Preferably, the bushing is a structure with a groove, and a through hole is provided at the bottom of the groove for cooperating with the valve core of the pilot gas valve to change the gas pressure in the groove; the bushing has two damping holes radially symmetrically arranged, which are generally circular through holes with a diameter of φ0.5 to 1.0 mm.

[0011] Preferably, there are two static seals between the bushing and the main valve body, one using a graphite sealing ring and the other using a sealing gasket.

[0012] Preferably, a heat insulation plate is provided between the main valve body and the pilot solenoid valve.

[0013] Preferably, the heat insulation board is made of high silica material.

[0014] Preferably, a positioning pin is provided between the housing of the pilot solenoid valve and the main valve body to ensure the sealing between the pilot valve core and the bushing of the pilot solenoid valve, and the coaxiality between the pilot valve core and the bushing of the pilot solenoid valve.

[0015] The beneficial effects of the present invention compared with the prior art are:

[0016] (1) The present invention adopts a two-stage structure and uses a pilot-stage solenoid valve to control the pressure of the pilot chamber, thereby changing the force direction of the main valve core to achieve a change in the outlet of the main gas channel. Compared with the commonly used direct-drive structure, under the same structural size, the driving force is greater and the energy consumption required to maintain the working condition is lower.

[0017] (2) In the present invention, a gap dynamic seal is used between the main valve core and the bushing, and a pressure equalizing groove is provided on the main valve core, which can effectively reduce the friction between the two. The friction force measured under cold air conditions is only 10N. This structure is used to further improve the valve opening and closing response.

[0018] (3) One of the two outlets of the gas valve of the present invention is always in an open state, which can ensure that the gas source system of special working media such as solid fuel gas will not be over-pressurized, and has good safety.

[0019] (4) The main gas channel and the pilot air inlet channel of the present invention are both on the main valve body, thus avoiding the need for additional pipeline connections for the pilot air inlet channel, and achieving high integration and connection reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural diagram of the present invention;

[0021] Figure 2 This is a partial enlarged view of the pilot cavity of the present invention;

[0022] Figure 3 This is a structural diagram of the main valve body of the present invention; DETAILED DESCRIPTION

[0023] The present invention will be further described below in conjunction with the embodiments.

[0024] like Figure 1 As shown, the gas valve of the present invention comprises a main valve body 1, a pilot solenoid valve 2, a main valve core 3, a limit nut 4, a bushing 5, a sealing gasket 6, a heat insulation plate 7, a retaining ring 8, and a graphite sealing ring 9; the main valve core 3 and the bushing 5 are made of the same material and have the same expansion coefficient, which can ensure that the deformation of the two is consistent when the temperature changes, so that the gap between the two can be kept relatively constant, and at the same time, the main valve core 3 and the bushing 5 are gap-sealed, and a pressure-equalizing groove is provided on the main valve core, which is arranged in the gap matching area between the main valve core and the bushing, and is a plurality of annular grooves; Figure 3As shown, the main valve body 1 is reserved with air intake channels for the left and right pilot solenoid valves 2. In the initial state, when the left and right solenoid coils are not energized, the gas entering the air intake channel of the pilot solenoid valve 2 is under the action of the damping hole of the bushing 5 (the two damping holes are symmetrically arranged in the radial direction of the bushing, generally circular through holes with a diameter of φ0.5-1.0 mm). The rear chambers A and B of the main valve core 3 are both in a low-pressure state, and the position of the main valve core is in a random state. The pressure relief ports of the two pilot solenoid valves 2 are exhausted normally. When the left pilot solenoid valve When the 2 coils are energized, the pilot valve core and the bushing 5 fit tightly. At this time, the pressure of the A chamber behind the main valve core 3 is consistent with the inlet pressure, which is a high-pressure state. At this time, since the right pilot solenoid valve 2 coil is not energized, the right B chamber behind the main valve core is still in a low-pressure state. In this way, the main valve core will receive a combined force to the right, and the left outlet of the gas valve will open, and the high-temperature gas will flow out from it; conversely, the right pilot solenoid valve 2 coil is energized and the left pilot solenoid valve 2 coil is de-energized, the right outlet of the gas valve will open, and the high-temperature gas will flow out from it. By alternately turning the power on and off on the left and right, the reciprocating motion of the main valve core can be realized to achieve the purpose of switching the outlet.

[0025] There are two static seals between the bushing 5 and the main valve body 1. Considering the coordination of the two seals, one is sealed with a graphite sealing ring 9 and the other is sealed with a sealing gasket 6. The graphite has a large compression amount and a large thermal expansion amount. Therefore, the two static seals can be reliably sealed under high temperature conditions; a heat insulation board 7 is arranged between the main valve body 1 and the pilot solenoid valve 2. The heat insulation board 7 is made of high silicon oxide material with low thermal conductivity, which can effectively isolate the heat from being conducted to the pilot solenoid valve 2; at the same time, in order to ensure the sealing between the pilot valve core of the pilot solenoid valve 2 and the bushing 5, a positioning pin is arranged between the two, which can maximize the coaxiality of the pilot valve core of the pilot solenoid valve 2 and the bushing 5, so that the two can be reliably sealed when the coil is energized, ensuring that the A (B) cavity is stably in a high-pressure state.

[0026] according to Figures 1 to 3 The driving force of the main valve core of the two-stage gas valve composed of the above-mentioned mechanism and connection relationship can easily reach the order of thousands of N, while the driving force of the valve core of a direct-drive structure valve under the same size condition is only 200-300N.

[0027] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A two-position three-way two-stage gas valve, characterized in that: Including main valve body, pilot solenoid valve, main valve core and bushing; Two main gas channels and a pilot air intake channel are arranged on the main valve body, sleeves and pilot solenoid valves are respectively installed at two ends of the main valve body, and air intake channels for two pilot solenoid valves are reserved on the main valve body. The main valve core is installed in the main valve body, and two cavities are formed between the two ends of the main valve core and the corresponding sleeves. When the pilot solenoid valves at both ends are not energized, the two cavities are both in a low-pressure state, the main valve core is in a random state, and the pressure relief ports of the two pilot solenoid valves are exhausted normally; when the pilot solenoid valve at one end is energized, the sleeve at this end fits tightly with the valve core of the pilot solenoid valve, the pressure in the cavity at this end is consistent with the inlet pressure and is higher than the pressure in the cavity at the other end, and the main valve core moves under the action of the cavity pressure difference to open the main gas channel on this side; the pilot solenoid valves at both ends are alternately powered on and off to realize the reciprocating motion of the main valve core, thereby achieving the purpose of switching the main gas channel.

2. The two-position three-way two-stage gas valve according to claim 1, characterized in that: A gap dynamic seal is adopted between the main valve core and the bushing.

3. The two-position three-way two-stage gas valve according to claim 1 or 2, characterized in that: The main valve core and bushing are made of the same material and have the same expansion coefficient.

4. The two-position three-way two-stage gas valve according to claim 1, characterized in that: The main valve core is provided with a pressure equalizing groove, which is arranged in the clearance matching area between the main valve core and the bushing and is a plurality of annular grooves, so as to avoid the main valve core and the bushing from being stuck to the greatest extent.

5. The two-position three-way two-stage gas valve according to claim 1, characterized in that: The bushing is a structure with a groove, and a through hole is set at the bottom of the groove for cooperating with the valve core of the pilot gas valve to change the gas pressure in the groove; the bushing has two damping holes arranged radially symmetrically, which are generally circular through holes with a diameter of φ0.5 to 1.

0.

6. The two-position three-way two-stage gas valve according to claim 1, characterized in that: There are two static seals between the bushing and the main valve body, one uses a graphite sealing ring and the other uses a sealing gasket.

7. The two-position three-way two-stage gas valve according to claim 1, characterized in that: A heat insulation plate is arranged between the main valve body and the pilot solenoid valve.

8. The two-position three-way two-stage gas valve according to claim 7, characterized in that: The heat insulation board is made of high silica material.

9. The two-position three-way two-stage gas valve according to claim 7, characterized in that: A positioning pin is arranged between the housing of the pilot solenoid valve and the main valve body to ensure the sealing between the pilot valve core and the bushing of the pilot solenoid valve, and the coaxiality between the pilot valve core of the pilot solenoid valve 2 and the bushing 5 .

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