A gas premixing valve of pneumatic type and a gas device

Abstract

The present application relates to a kind of gas premixing valve of pneumatic type, including valve body, valve body is equipped with gas inlet, gas outlet, inside gas inlet is equipped with first cavity, control cavity, outlet cavity in proper order, first cavity is controlled to open and close by first electromagnetic valve between control cavity, control cavity and outlet cavity are equipped with regulating valve on;Control cavity and regulating valve are equipped with the first branch passage of intercommunication, outlet cavity is equipped with servo valve, servo valve includes second diaphragm, second diaphragm and valve body form second diaphragm cavity, second diaphragm cavity and first diaphragm cavity are equipped with second branch passage, second branch passage and outlet cavity are controlled to open and close and opening degree by second valve plug.This application can be dynamically adjusted opening degree according to gas inlet pressure and air line pressure by the branch passage linkage of first diaphragm cavity and second diaphragm cavity, combined with the cooperation of servo valve and regulating valve.Gas-air pressure difference real-time compensation, ensure that air-fuel ratio is stable, avoid the problem of insufficient combustion or backfire.

Description

Technical Field

[0001] This invention relates to a gas valve, and more particularly to a gas valve for use with natural gas. Background Technology

[0002] Gas water heaters rely entirely on solenoid valves for regulation and control during operation. However, existing regulating valves cannot automatically adjust based on the pressure difference between the outlet and inlet gas pressures when gas and inlet pressures change. This leads to corresponding changes in the combustion conditions in the combustion chamber, and requires complex calculation logic for adjustment. Furthermore, because gas pressure and combustion air inlet pressure are variable, the air-gas mixing ratio is difficult to coordinate, resulting in an unreasonable combustion ratio and excessive exhaust gases. Therefore, there is an urgent need for a gas valve that can actively regulate the combustion air-gas ratio. Summary of the Invention

[0003] To address the aforementioned shortcomings of existing gas valves, this invention provides a pneumatic gas premixing valve that actively adjusts the valve body based on the pressure difference between the inlet and outlet pressures to achieve the set outlet pressure or flow rate requirements.

[0004] The technical solution adopted in this invention is as follows: a pneumatic gas premixing valve, comprising a valve body, the valve body having a gas inlet and a gas outlet, a first cavity, a control cavity, and an outlet cavity sequentially arranged inside the gas inlet, the first cavity and the control cavity being controlled to open and close by a first solenoid valve, the control cavity and the outlet cavity being provided with a regulating valve; a first branch connecting the control cavity and the regulating valve is provided, the regulating valve including a first diaphragm, the first diaphragm being provided with a first valve stem and a first valve plug, the first diaphragm having a first diaphragm cavity on its outer side, the first branch connecting to the first diaphragm cavity; a driven valve linked to the first solenoid valve is provided on the first branch, the regulating valve controlling the opening and closing of the valve body and its opening degree by the pressure of the first diaphragm cavity; a servo valve is provided on the outlet cavity, the servo valve including a second diaphragm, the second diaphragm being provided with a second valve stem and a second valve plug, the second diaphragm and the valve body forming a second diaphragm cavity, a second branch connecting the first diaphragm cavity and the second diaphragm cavity, the second branch and the outlet cavity being controlled to open and close and their opening degree by a second valve plug. The valve body is covered with a cover plate, and the first diaphragm cavity is formed by the cover plate and the first diaphragm.

[0005] The valve body also includes a base and a pressure plate covering the base, with a sealing gasket between the pressure plate and the base; the first valve body, the second valve body, and the servo valve are mounted on the pressure plate. The sealing and fixing of the first valve body, the second valve body, and the pressure plate is a conventional technique in this field and will not be elaborated upon further.

[0006] As a preferred embodiment of a pneumatic gas premixed valve, the valve body is constructed using a solenoid valve previously applied for by our company. The first solenoid valve includes a valve seat, a coil located inside the valve seat, and a first valve stem located in the middle of the coil. A first valve plug is provided at the end of the first valve stem. A spring is sleeved on the first valve stem and presses against the valve plug to keep the solenoid valve in a normally closed state. The driven valve is located inside the valve seat and includes a fourth iron core. A fourth valve plug is provided on the fourth iron core.

[0007] As a preferred option for a pneumatic gas premixed valve, the servo valve can be an electromagnetic servo valve, which regulates the opening and closing degree through a combination of electrical control and pressure in the second diaphragm chamber.

[0008] As a preferred embodiment of a pneumatic gas premixed valve, the second diaphragm of the servo valve is provided with a signal chamber on the other side. The signal chamber is provided with an interface for connecting with the air intake pipe. The servo valve can adjust the opening degree in conjunction with the pressure in the first diaphragm chamber and the air intake pipe. A spring is provided at the rear end of the second valve plug, and the other end of the spring is provided on the screw plug. The spring preload can be adjusted by rotating and adjusting the position of the screw plug.

[0009] As one of the preferred options for a pneumatic gas premixed valve, the outlet of the gas outlet chamber is equipped with a flow regulator. The flow regulator includes a valve plate located at the outlet, a rotatable screw on the valve plate, the screw being located in an adjusting screw hole, and a sealing ring between the screw and the adjusting screw hole.

[0010] As one of the preferred options for a pneumatic gas premixed valve, it also includes an inlet pressure measuring port on the regulating valve and an outlet pressure measuring port located in the outlet chamber.

[0011] A gas device includes a pneumatic gas premixing valve and an air pipeline. One end of the air pipeline is provided with an air blowing device, the middle of the air pipeline is provided with an air throttle, the gas outlet is connected to and provided with a gas injection mechanism, the air throttle is located outside the air pipeline, and the end of the air pipeline is provided with a combustion chamber.

[0012] In a further preferred embodiment, the air pipe and the inner side of the air throttle are connected to the signal cavity via a signal pipe. When the air pipe passes through the air throttle, the area decreases and the flow velocity increases, at which point the gas in the combustion pipe is carried in and out to the combustion chamber.

[0013] The beneficial effects of this invention are as follows: by linking the branches of the first diaphragm cavity and the second diaphragm cavity, and in conjunction with the cooperation of the servo valve and the regulating valve, the opening can be dynamically adjusted according to the gas intake pressure and the air pipeline pressure. The second diaphragm cavity introduces an air pressure signal to achieve real-time compensation for the gas-air pressure difference, ensuring a stable air-fuel ratio and avoiding incomplete combustion or backfire problems.

[0014] The mechanical linkage design between the first solenoid valve and the driven valve achieves rapid switching of the control chamber pressure through the synchronous action of the fourth iron core. The normally closed spring structure of the solenoid valve automatically cuts off the gas passage when power is off. Combined with the adjustable spring pressure design of the servo valve, multiple safety redundancies are formed, significantly improving system safety.

[0015] The valve plug is self-driven by the pressure of the diaphragm chamber (first diaphragm chamber and second diaphragm chamber), and the valve opening and closing is realized by the potential energy of the gas pressure, reducing the dependence on external power. The combined regulation of electric control and pneumatic pressure of the servo valve can adapt to complex working conditions, reduce the energy consumption of electromagnetic components and extend the service life while maintaining the regulation accuracy.

[0016] The three-chamber layered design (first chamber - control chamber - outlet chamber) combined with the bracket limiting valve stem structure reduces turbulence interference; moreover, all adjustment and pressure measurement ports are ensured to be on the same side for easy user adjustment. The screw seal structure of the flow regulator allows for linear adjustment of the outlet gas volume, while closed-loop monitoring is achieved through the inlet / outlet pressure measurement ports, facilitating precise matching of combustion load requirements.

[0017] The gas appliance utilizes the air pressure signal generated by the Tully effect in fluid dynamics to drive the opening adjustment of the gas valve, achieving automatic matching and regulation of the gas flow. The gas valve in this project consists of two double-loop solenoid valves and one servo valve.

[0018] The gas flow rate is regulated by the air intake, filter, solenoid valve, and servo valve. The servo valve is driven by air pressure signal, and a linear relationship is established between air pressure and gas pressure. This ensures that the air and gas are always mixed in a reasonable and fixed ratio throughout the combustion process, resulting in complete combustion. Attached Figure Description

[0019] Figure 1 This is a cross-sectional view of an embodiment of the present invention.

[0020] Figure 2 This is a cross-sectional view of Embodiment 2 of the present invention.

[0021] Figure 3 This is a schematic diagram of the gas device structure of the present invention.

[0022] Wherein: 1. Valve body; 11. Gas inlet; 12. Gas outlet; 21. First cavity; 22. Control cavity; 23. Gas outlet cavity; 31. First solenoid valve; 32. Regulating valve; 33. First branch; 321. First diaphragm; 322. First valve stem; 323. First valve plug; 324. First diaphragm cavity; 310. Driven valve; 34. Servo valve; 341. Second diaphragm; 342. Second valve stem; 343. Second valve plug; 344. Second diaphragm cavity; 35. 1. Second branch; 2. Cover plate; 311. Valve seat; 312. Coil; 315. Fourth iron core; 316. Fourth valve plug; 4. Signal chamber; 41. Interface; 42. Screw plug; 44. Flow regulator; 45. Valve plate; 46. Screw; 51. Inlet pressure test port; 52. Outlet pressure test port; 53. Outlet plug; 54. Bracket; 55. Flange; 6. Solenoid valve; 7. Air pipeline; 71. Air blowing device; 8. Air throttle; 9. Combustion chamber; 10. Signal tube. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings.

[0024] It should be noted that the terms "first" and "second" below are only used to distinguish one component from another and do not have any specific meaning. The terms "upper" and "lower" are only defined for the convenience of illustration in the attached drawings and are not relative to the absolute position of the product.

[0025] Example 1: As Figure 1As shown: A pneumatic gas premixing valve includes a valve body 1, which has a gas inlet 11 and a gas outlet 12. Inside the gas inlet 11, a first cavity 21, a control cavity 22, and an outlet cavity 23 are sequentially arranged. The first cavity 21 and the control cavity 22 are controlled to open and close by a first solenoid valve 631. A regulating valve 32 is provided on the control cavity 22 and the outlet cavity 23. A first branch 33 connects the control cavity 22 and the regulating valve 32. The regulating valve 32 includes a first diaphragm 321, on which a first valve stem 322 and a first valve plug 323 are arranged. The first diaphragm 321 has a first diaphragm on its outer side. The valve body 1 is connected to the first diaphragm 321 cavity via a first branch 33. A driven valve 310, linked to the first solenoid valve 631, is installed on the first branch 33. A regulating valve 32 controls the opening and closing of the valve body 1 and its opening degree via the pressure in the first diaphragm 321 cavity. A servo valve 34 is installed on the outlet chamber 23. The servo valve 34 includes a second diaphragm 341, with a second valve stem and a second valve plug. The second diaphragm 341 and the valve body 1 form the second diaphragm 341 cavity. A second branch 35 is provided between the first diaphragm 321 cavity and the second diaphragm 341 cavity. The second branch 35 and the outlet chamber 23 are controlled by the second valve plug to open and close. A cover plate 2 is provided on the valve body 1, and the first diaphragm 321 cavity is formed by the cover plate 2 and the first diaphragm 321. After the gas enters the inlet, it fills the first chamber 21. When the first solenoid valve 631 is opened, the gas enters the control chamber 22, and the driven valve 310 opens synchronously with the first solenoid valve 631. The gas pressure filling the control chamber 22 enters the first diaphragm 321 chamber through the first branch 33. The diaphragm is pushed by the pressure to open the regulating valve 32. The first diaphragm 321 chamber and the second diaphragm 341 chamber are connected through the second branch 35. When the pressure in the first diaphragm 321 chamber is too high, it will cause the opening to be too large. At this time, the pressure in the second diaphragm 341 chamber increases synchronously, thereby opening it and pushing open the second valve plug to connect the interior with the outlet chamber 23.

[0026] The first solenoid valve 631 includes a valve seat 311, a coil 312 located in the valve seat 311, and a first valve stem 313 located in the middle of the coil 312. The first valve stem 313 has a first valve plug 314 at its end. A spring is sleeved on the first valve stem 313 and the spring presses against the valve plug to keep the solenoid valve 6 (which is confused with the servo solenoid valve 6 and needs to be distinguished) in a normally closed state. The driven valve 310 is disposed in the valve seat 311. The driven valve 310 includes a fourth iron core 315 and a fourth valve plug 316 is provided on the fourth iron core 315.

[0027] The servo solenoid valve 6 is equipped with a limit pressure regulating device, which was previously applied for by our company, at its top. A maximum pressure limit nut is located on the upper part of the solenoid valve 6, and a small pressure pre-adjustment knob is adjusted on the limit nut. The end of the internal movable iron core passes through the limit nut and is equipped with a retaining spring. The retaining spring is limited by the limit nut, further restricting the maximum downward displacement of the internal movable iron core. A small pre-adjustment spring is located between the retaining spring and the small pre-adjustment nut, which allows for factory pre-adjustment of the minimum outlet flow rate or pressure.

[0028] It can also be coordinated with the circuit controller for program-based joint control. Through feedback of combustion conditions, the current of the input solenoid valve 6 can be adjusted to achieve stepless regulation of the gas flow rate or pressure.

[0029] In this embodiment, the servo valve 34 is a solenoid valve 6. The servo valve 34 adjusts its opening and closing degree through a combination of electronic control and pressure in the second diaphragm 341 chamber. The solenoid valve 6 can adjust its opening and closing degree through pressure linkage between the inlet pressure measuring port 51 and the outlet pressure measuring port 52.

[0030] Example 2: According to Figure 2As shown: A pneumatic gas premixing valve includes a valve body 1, which has a gas inlet 11 and a gas outlet 12. Inside the gas inlet 11, a first cavity 21, a control cavity 22, and an outlet cavity 23 are sequentially arranged. The first cavity 21 and the control cavity 22 are controlled to open and close by a first solenoid valve 631. A regulating valve 32 is provided on the control cavity 22 and the outlet cavity 23. A first branch 33 connects the control cavity 22 and the regulating valve 32. The regulating valve 32 includes a first diaphragm 321, on which a first valve stem 322 and a first valve plug 323 are arranged. The first diaphragm 321 has a first diaphragm on its outer side. The valve body 1 is connected to the first diaphragm 321 cavity via a first branch 33. A driven valve 310, linked to the first solenoid valve 631, is installed on the first branch 33. A regulating valve 32 controls the opening and closing of the valve body 1 and its opening degree via the pressure in the first diaphragm 321 cavity. A servo valve 34 is installed on the outlet chamber 23. The servo valve 34 includes a second diaphragm 341, with a second valve stem and a second valve plug. The second diaphragm 341 and the valve body 1 form the second diaphragm 341 cavity. A second branch 35 is provided between the first diaphragm 321 cavity and the second diaphragm 341 cavity. The second branch 35 and the outlet chamber 23 are controlled by the second valve plug to open and close. A cover plate 2 is provided on the valve body 1, and the first diaphragm 321 cavity is formed by the cover plate 2 and the first diaphragm 321. After the gas enters the inlet, it fills the first chamber 21. When the first solenoid valve 631 is opened, the gas enters the control chamber 22, and the driven valve 310 opens synchronously with the first solenoid valve 631. The gas pressure filling the control chamber 22 enters the first diaphragm 321 chamber through the first branch 33. The diaphragm is pushed by the pressure to open the regulating valve 32. The first diaphragm 321 chamber and the second diaphragm 341 chamber are connected through the second branch 35. When the pressure in the first diaphragm 321 chamber is too high, it will cause the opening to be too large. At this time, the pressure in the second diaphragm 341 chamber increases synchronously, thereby opening it and pushing open the second valve plug to connect the interior with the outlet chamber 23.

[0031] The first solenoid valve 631 includes a valve seat 311, a coil 312 located in the valve seat 311, and a first valve stem 313 located in the middle of the coil 312. A first valve plug 314 is provided at the end of the first valve stem 313. A spring is sleeved on the first valve stem 313 and the spring presses against the valve plug so that the first valve plug 314 is in a normally closed state. A driven valve 310 is provided in the valve seat 311. The driven valve 310 includes a fourth iron core 315 and a fourth valve plug 316 is provided on the fourth iron core 315.

[0032] In this embodiment, the servo valve 34 has a signal chamber 4 on the other side of the second diaphragm 341. The signal chamber 4 has an interface 41 for communicating with the air intake pipe. The servo valve 34 can adjust its opening degree in conjunction with the pressure in the first diaphragm 321 chamber and the air intake pipe. A spring is mounted on the rear end of the second valve plug, and the other end of the spring is mounted on the screw plug 42. The spring pressure can be adjusted by rotating the screw plug 42. The signal chamber 4 is adjusted in conjunction with the pressure in the gas-air pipeline 7, the spring, and the pressure in the second diaphragm 341 chamber, so that the gas rate is linked to the air intake pressure. The higher the air intake pressure, the greater the tolerance of the second diaphragm 341 chamber. This coordinated adjustment effectively improves the gas combustion efficiency. When the air pressure decreases, it can quickly open the second diaphragm 341 chamber, reduce gas emissions, and avoid incomplete combustion that produces harmful gases.

[0033] In this embodiment, to avoid the pressure in the air outlet chamber 23 being too low, the air outlet of the air outlet chamber 23 is provided with a flow regulator 44. The flow regulator 44 includes a valve plate 45 covering the air outlet. A screw 46 is rotatably provided on the valve plate 45. The screw 46 is screwed into the adjusting screw hole. A sealing ring is provided between the screw 46 and the adjusting screw hole.

[0034] A gas device, such as Figure 3 As shown: It includes a pneumatic gas premixing valve, an air pipeline, an air blowing device at one end of the air pipeline, an air throttle in the middle of the air pipeline, a gas outlet connected to and equipped with a gas injection mechanism, a combustion chamber at the end of the air pipeline outside the air throttle.

[0035] In this embodiment, when the valve body adopts the scheme of Embodiment 2, the air pipeline and the inner side of the air throttle are connected to the signal cavity through a signal pipe. The air pipeline experiences a sudden decrease in inner diameter due to the air throttle, resulting in an increase in flow velocity. At this time, the gas in the combustion pipeline will be carried in and out to the combustion chamber.

[0036] The above are merely specific embodiments of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A pneumatic gas premixing valve, comprising a valve body (1), wherein the valve body (1) is provided with a gas inlet (11) and a gas outlet (12), wherein a first cavity (21), a control cavity (22), and an outlet cavity (23) are sequentially provided inside the gas inlet (11), wherein the first cavity (21) and the control cavity (22) are controlled to open and close by a first solenoid valve (6) (31), wherein a regulating valve (32) is provided on the control cavity (22) and the outlet cavity (23); wherein a first connecting branch is provided between the control cavity (22) and the regulating valve (32). The regulating valve (32) includes a first diaphragm (321), on which a first valve stem (322) and a first valve plug (323) are provided. The outer side of the first diaphragm (321) has a first diaphragm (321) cavity, and the first branch (33) is connected to the first diaphragm (321) cavity. The first branch (33) is provided with a driven valve (310) that is linked with the first solenoid valve (6) (31). The regulating valve (32) controls the opening and closing of the valve body (1) and the opening degree through the pressure of the first diaphragm (321) cavity. The air outlet chamber (23) is provided with a servo valve (34). The servo valve (34) includes a second diaphragm (341). The second diaphragm (341) is provided with a second valve stem and a second valve plug. The second diaphragm (341) and the valve body (1) form a second diaphragm (341) cavity. A second branch (35) is provided between the first diaphragm (321) cavity and the second diaphragm (341) cavity. The second branch (35) and the air outlet chamber (23) are controlled to open and close and to open degree by the second valve plug.

2. The pneumatic gas premixing valve according to claim 1, characterized in that: The valve body (1) is sealed with a cover plate (2), and the cover plate (2) and the first diaphragm (321) form the cavity of the first diaphragm (321).

3. The pneumatic gas premixing valve according to claim 2, characterized in that: The first solenoid valve (6) (31) includes a valve seat (311), a coil (312) located in the valve seat (311), and a first valve stem (313) located in the middle of the coil (312). The first valve stem (313) has a first valve plug (314) at its end. A spring is sleeved on the first valve stem (313) and the spring presses against the valve plug to keep the solenoid valve (6) in a normally closed state. The driven valve (310) is located in the valve seat (311). The driven valve (310) includes a fourth iron core (315) and a fourth valve plug (316) is provided on the fourth iron core (315).

4. The pneumatic gas premixing valve according to claim 3, characterized in that: The servo valve (34) has a signal chamber (4) on the other side of the second diaphragm (341). The signal chamber (4) has an interface (41) for connecting with the air intake pipe. The servo valve (34) can adjust the opening degree in conjunction with the pressure in the first diaphragm (321) chamber and the air intake pipe. The rear end of the second valve plug is provided with a spring, and the other end of the spring is provided on the screw plug (42). The spring pressure can be adjusted by rotating the screw plug to adjust the position.

5. The pneumatic gas premixing valve according to claim 4, characterized in that: The outlet of the air chamber (23) is provided with a flow regulator (44). The flow regulator (44) includes a valve plate (45) covering the outlet. A screw (46) is rotatably provided on the valve plate (45). The screw (46) is located in an adjusting screw hole. A sealing ring is provided between the screw (46) and the adjusting screw hole.

6. The pneumatic gas premixing valve according to claim 1, characterized in that: It also includes an air inlet pressure measuring port (51) connected to the control chamber (22) and an air outlet pressure measuring port (52) connected to the air outlet chamber (23).

7. The pneumatic gas premixing valve according to claim 1, characterized in that: An opening is provided between the control chamber (22) and the air outlet chamber (23). The valve stem of the regulating valve (32) passes through the opening. An air outlet plug (53) is provided at the upper end of the valve stem located in the regulating chamber. The valve stem also includes a bracket (54) fixed on the opening for limiting and passing through the valve stem. A flange (55) is provided at the lower end of the valve stem. The valve stem also includes a spring that is positioned between the bracket (54) and the flange (55).

8. The pneumatic gas premixing valve according to claim 3, characterized in that: The servo valve (34) can also be a solenoid valve (6). The solenoid valve adjusts the opening of the second valve plug steplessly by changing the input current and in conjunction with the pressure in the second diaphragm (341) chamber, thereby achieving stepless adjustment of the outlet pressure or flow rate.

9. A gas device comprising a pneumatic gas premixing valve as described in any one of claims 1 to 8, characterized in that: It also includes an air duct (7), one end of which is provided with an air blowing device (71), the middle of which is provided with an air throttle (8), the gas outlet (12) is connected to the outside of the air throttle (8), and the end of which is provided with a combustion chamber (9).

10. The gas-fired device according to claim 9, characterized in that: The air duct (7) and the inner side of the air throttle (8) are connected to the signal cavity (4) through the signal tube (10).

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