A pull smoke electromagnetic valve with position feedback and cleaning function

Abstract

The application discloses a smoke pulling electromagnetic valve with position feedback and cleaning functions. The smoke pulling electromagnetic valve comprises a shell, a main valve cavity is arranged in the shell, the main valve cavity is communicated with an inlet channel, an outlet channel and a cleaning cavity respectively, a main valve core, a top rod and a bellows are arranged in the main valve cavity, one end of the top rod is connected with the main valve core, the other end of the top rod is connected with a piston in a piston cavity after penetrating through a cavity wall of the main valve cavity, the bellows is sleeved on the top rod and connected with the main valve core and the inner wall of the main valve cavity at two ends respectively, the piston is provided with a reset spring, the piston cavity is communicated with external atmosphere and a pilot channel through a pilot valve assembly respectively, and a cleaning valve assembly is arranged in the cleaning cavity. The application solves the problems of smoke pulling liquid residue, sealing wear and product damage in the smoke pulling valve.

Description

Technical Field

[0001] This invention belongs to the technical field of smoke extraction devices for trainer aircraft, specifically relating to a smoke extraction solenoid valve with position feedback and cleaning functions. Background Technology

[0002] Previously, the smoke extraction systems of trainer aircraft used electric ball valves. The principle was that an electric mechanism, when energized, rotated the ball valve to control the flow of smoke extraction fluid. The ball valve was pressed against non-metallic materials to ensure a seal. However, with prolonged use, after the ball valve and sealing material wore down to a certain extent, the seal could no longer be guaranteed, leading to leakage of the working medium. Furthermore, the smoke extraction fluid has strong adhesion and gradually accumulates at the outlet of the smoke extraction valve during use. As the fluid dries, it gradually blocks the outlet, affecting the smoke extraction effect. Severe accumulation also increases the opening torque of the ball valve, reducing product reliability. If the electric mechanism is damaged in the open position, the product will be unable to close. In summary, the previous structure cannot meet the requirements of future trainer aircraft. Summary of the Invention

[0003] The purpose of this invention is to provide a smoke extraction solenoid valve with position feedback and cleaning functions. This invention solves the problems of smoke extraction liquid residue, seal wear, and inability to close the valve after product damage.

[0004] The technical solution of this invention is: a smoke-discharging solenoid valve with position feedback and cleaning functions, comprising a housing, a main valve cavity disposed within the housing, the main valve cavity being connected to an inlet channel, an outlet channel, and a cleaning chamber respectively; a main valve assembly disposed within the main valve cavity; the main valve assembly comprising a main valve core, a push rod, and a bellows, one end of the push rod being connected to the main valve core, and the other end passing through the cavity wall of the main valve cavity and connected to a piston in the piston chamber; the bellows being sleeved on the push rod body, and both ends being connected to the main valve core and the inner wall of the main valve cavity respectively; a return spring being disposed on the piston, and the piston cavity being connected to the external atmosphere and a pilot channel respectively via a pilot valve assembly; a cleaning valve assembly disposed within the cleaning chamber.

[0005] In the aforementioned smoke-pulling solenoid valve with cleaning and position feedback functions, the cleaning valve assembly includes a cleaning valve seat, and the cleaning valve seat and the cleaning valve core can form a conical seal.

[0006] In the aforementioned smoke-pulling solenoid valve with cleaning and position feedback functions, a throttling seat is provided in the cleaning chamber inside the cleaning valve seat, and a throttling orifice is provided on the throttling seat.

[0007] In the aforementioned smoke-pulling solenoid valve with cleaning and position feedback functions, the width of the conical seal is 0.1 to 0.2 mm, and the surface roughness is 0.2.

[0008] In the aforementioned smoke-pulling solenoid valve with cleaning and position feedback functions, the main valve core and the inner end face of the inlet channel can form an end face seal.

[0009] In the aforementioned smoke-pull solenoid valve with cleaning and position feedback functions, the width of the sealing strip on the end face is 0.1 to 0.2 mm, and the surface roughness is 0.2.

[0010] In the aforementioned smoke-pulling solenoid valve with cleaning and position feedback functions, a micro switch is provided in the extension direction of the piston axis.

[0011] In the aforementioned smoke-pulling solenoid valve with cleaning and position feedback functions, the pilot channel is also connected to the inner cavity of the bellows via a pressure-holding channel.

[0012] In the aforementioned smoke-pulling solenoid valve with cleaning and position feedback functions, a one-way valve is provided in the pilot channel.

[0013] The advantages of this invention are as follows: The invention incorporates a cleaning valve structure on the smoke extraction solenoid valve. After the main valve of the smoke extraction solenoid valve is closed, a certain pressure of gas can be introduced into the cleaning valve inlet. After passing through a flow-limiting cascade, the high-speed gas discharges the residual smoke extraction liquid in the product's inner cavity and outlet pipe, preventing the residual liquid from drying and accumulating in the product's inner cavity, thus affecting the product's opening and closing. The product valve adopts a bellows valve design, with a metal-to-metal flat seal, eliminating wear. The product uses a pilot-operated solenoid valve structure; the product opens when the electromagnet is energized and closes when de-energized. If the product malfunctions, the electromagnet is de-energized, and the product can be reset and closed under spring force, improving the reliability of the product's closing and ensuring system safety.

[0014] To ensure the sealing reliability of the main valve when closed, this invention increases the closing force, such as... Figure 1 As shown, the pilot channel is also connected to the inner cavity of the bellows via a pressure-holding channel. When the product is closed, the sealing of the main valve is ensured by the spring force and the air pressure in the inner cavity of the bellows.

[0015] When the product is shut down and ventilating for cleaning, because the cleaning valve assembly and pilot channel share the same air source, after the cleaning valve assembly opens and the vent is connected to the atmosphere, the pressure at the pilot channel decreases, and the pressure inside the bellows also decreases. At this time, the closing force exerted by the bellows on the main valve decreases, resulting in insufficient sealing pressure and increased leakage. To solve this technical problem, this invention incorporates a one-way valve in the pilot channel to maintain pressure in the pilot channel, thereby ensuring a constant pressure inside the bellows cavity and guaranteeing the reliability of the main valve's closure.

[0016] In summary, the smoke extraction solenoid valve of this invention, with its washable structure, ensures timely cleaning of the product's internal cavity after use. The valve employs a welded bellows design, guaranteeing high reliability and long service life while preventing media leakage. It meets the requirements for use in training aircraft.

[0017] This product guarantees zero leakage of the main valve at 0.8MPa. Both dynamic and static seals at all points on the product ensure zero leakage, and external leakage is zero in both open and closed states. Tests have verified that the product meets the lifespan requirement of 10,000 opening and closing cycles. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the present invention. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.

[0020] Example 1. A smoke extraction solenoid valve with position feedback and cleaning function, see [link to example]. Figure 1 The system includes a housing 1, a main valve cavity 2 inside the housing 1, which is connected to an inlet channel 3, an outlet channel 4, and a cleaning chamber 5. A main valve assembly 6 is installed inside the main valve cavity 2. The main valve assembly 6 includes a main valve core 61, a push rod 62, and a bellows 63. One end of the push rod 62 is connected to the main valve core 61, and the other end passes through the cavity wall of the main valve cavity 2 and is connected to a piston 8 in a piston chamber 7. The bellows 63 is fitted onto the push rod 62, and both ends are connected to the main valve core 61 and the inner wall of the main valve cavity 2, respectively. A return spring 9 is installed on the piston 8. The piston chamber 7 is connected to the external atmosphere and a pilot channel 11 via a pilot valve assembly 10. A cleaning valve assembly 12 is installed inside the cleaning chamber 5.

[0021] The cleaning valve assembly 12 includes a cleaning valve seat 121, which and the cleaning valve core 122 can form a conical seal.

[0022] A throttling seat 13 is provided inside the cleaning chamber 5 on the inner side of the cleaning valve seat 121, and a throttling orifice 14 is provided on the throttling seat 13. This structure can throttle the gas, increase the gas flow rate, and increase the cleaning efficiency.

[0023] The main valve core 61 and the inner end face of the inlet channel 3 can form an end face seal.

[0024] The width of the sealing strip for end face sealing is 0.1 to 0.2 mm, and the surface roughness is 0.2.

[0025] The seal at this location uses a flat plate seal with a strict leakage control requirement of 3 ml / min. Multiple rounds of testing and verification were conducted to ensure sealing performance. Considering the stringent sealing requirements, a metal + vulcanized rubber seal was initially used, which provided good sealing. However, most rubbers are not resistant to smoke-generating agents, and they tend to expand over time. Furthermore, the smoke-generating agent contains many impurities, which can easily damage the sealing surface. After a certain number of opening and closing cycles, the rubber surface was severely damaged, and leakage exceeded the tolerance. Secondly, considering the medium's resistance and impurities, a metal + plastic flat plate seal was adopted, with an interference fit plastic sealing ring in the valve seat. This provided good sealing, but after repeated opening and closing, the interference-fit plastic ring dislodged. The plastic has relatively low hardness, making the interference fit unreliable. The final design employs a metal-on-metal flat plate seal. To ensure adequate leakage control, the valve seat is designed as a flat plate with a surface roughness of 0.2, and the valve itself is frustum-shaped. Before assembly, the valve and valve seat are lapped together to ensure the sealing surface width is within a certain range. A narrow sealing surface results in a high sealing pressure, which can damage the sealing surface with frequent opening and closing. Conversely, a wide sealing surface leads to insufficient sealing pressure and inadequate leakage control. After calculation and preliminary testing, a sealing surface width of 0.1–0.2 mm was determined to guarantee both sealing performance and the required number of sealing cycles. The sealing strip for the conical seal described below was also determined after similar analysis and research.

[0026] The width of the sealing strip of the conical seal is 0.1 to 0.2 mm, and the surface roughness is 0.2.

[0027] A microswitch 15 is provided along the extension direction of the piston 8's axis. This sends a signal to the control system.

[0028] The pilot channel 11 is also connected to the inner cavity of the bellows 63 via the pressure-holding channel 16. Gas is introduced into the bellows 63 to increase the pressure of the main valve core 61 on the inlet channel 3, thereby enhancing the reliability of the main valve core 61 in sealing the inlet channel 3.

[0029] A one-way valve 17 is provided in the pilot channel 11.

[0030] Pilot valve assembly 10 controls pilot channel 11 to connect with piston chamber 7. Pilot gas enters piston chamber 7 through pilot channel 11, pushing piston 8 to move, which in turn drives main valve core 61 to move, opening inlet channel 3, allowing high-pressure e-liquid to enter through inlet channel 3 and exit through outlet channel 4. During cleaning, pilot valve assembly 10 controls piston chamber 7 to connect with the external atmosphere. Piston chamber 7 is reset by return spring 9, and the gas in piston chamber 7 is discharged. At the same time, main valve core 61 re-closes inlet channel 3. Cleaning valve assembly 12 opens, and cleaning gas is sprayed from cleaning chamber 5 into main valve chamber 2, blowing out residual e-liquid in main valve assembly 6 and valve chamber 2 through outlet channel 4.

Claims

1. A pull smoke solenoid valve having a cleaning and position feedback function, characterized by, The system includes a housing, within which a main valve cavity is provided, communicating with an inlet channel, an outlet channel, and a cleaning chamber. A main valve assembly is housed within the main valve cavity. The main valve assembly includes a main valve core, a push rod, and a bellows. One end of the push rod is connected to the main valve core, and the other end extends through the cavity wall of the main valve cavity and connects to a piston in the piston chamber. The bellows is fitted around the push rod, with both ends connected to the main valve core and the inner wall of the main valve cavity, respectively. A return spring is provided on the piston, and the piston chamber is connected to the external atmosphere and a pilot channel via a pilot valve assembly. A cleaning valve assembly is housed within the cleaning chamber. The cleaning valve assembly includes a cleaning valve seat, and the cleaning valve seat and the cleaning valve core can form a conical seal; A throttling seat is provided inside the cleaning chamber on the inner side of the cleaning valve seat, and a throttling orifice is provided on the throttling seat; The width of the sealing strip of the conical seal is 0.1–0.2 mm, and the surface roughness is 0.

2. The pilot channel is also connected to the inner cavity of the bellows via a pressure-holding channel.

2. The smoke-pull solenoid valve with cleaning and position feedback functions according to claim 1, characterized in that, The main valve core and the inner end face of the inlet channel can form an end face seal.

3. The smoke-pull solenoid valve with cleaning and position feedback functions according to claim 2, characterized in that, The width of the sealing strip for end face sealing is 0.1 to 0.2 mm, and the surface roughness is 0.

2.

4. The smoke extraction solenoid valve with cleaning and position feedback functions according to claim 1, characterized in that, A microswitch is provided along the extension direction of the piston axis.

5. The smoke extraction solenoid valve with cleaning and position feedback functions according to claim 1, characterized in that, A one-way valve is installed in the pilot channel.

Images