Pneumatic valve device for small-caliber pipe

Abstract

The pneumatic valve device comprises a valve body, connecting flanges are arranged at the front end and the rear end of the valve body through a front lock and a rear lock respectively, a fluid channel communicated with the front connecting flange and the rear connecting flange is arranged in the valve body, a corrugated pipe is arranged in the fluid channel, and the telescopic end of the corrugated pipe faces the inlet end of the fluid channel; an air chamber communicated with an inner cavity of the corrugated pipe is arranged at the rear end of the corrugated pipe, an air cylinder is arranged in the air chamber through an air cylinder seat, and the end of an air cylinder telescopic rod is connected to the inner wall of the telescopic end of the corrugated pipe. An air inlet and two switch control valves communicated with the air inlet are arranged on the side wall of the valve body. The corrugated pipe is driven by compressed air to deform, reliable control over on-off of liquid is achieved, due to the fact that the corrugated pipe has high sealing performance and high response speed, the corrugated pipe is widely suitable for precise conveying scenes of high-purity, corrosive or highly toxic chemicals, and zero-leakage conveying of fluid is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of industrial automation fluid control, more particularly to a pneumatic valve device for small-bore pipe. BACKGROUND

[0002] The pneumatic valve is an automatic control valve with compressed air as the power source, which is composed of a pneumatic actuator and a valve body. It is widely used in the field of precise regulation of gas or liquid flow. The existing pneumatic valve is mostly single-acting pneumatic cylinder, which relies on spring reset. The piston in the cylinder has large movement resistance, resulting in long opening and closing time, which is difficult to meet the demand of high-frequency and rapid switching. The structure of the commonly used pneumatic valve is complex, mostly integrated with electromagnetic valve, sensor and other components, which has large volume and complicated assembly, resulting in increased cost of the pneumatic valve and limited installation space. SUMMARY

[0003] The present application needs to solve the technical problem of providing a pneumatic valve device for small-bore pipe, which realizes the technical effects of zero leakage, corrosion resistance and fast response by optimizing the structure of the bellows, the layout of the gas circuit and the sealing form.

[0004] To solve the above technical problems, the technical solutions adopted by the present application are as follows.

[0005] The pneumatic valve device for small-bore pipe comprises a valve body, a front connecting flange and a rear connecting flange are arranged at the front and rear ends of the valve body respectively through front locking and rear locking for installing the pneumatic valve device, a fluid passage is arranged in the valve body for connecting the front and rear connecting flanges, a bellows is arranged in the fluid passage for opening and closing the fluid passage, and the extension end of the bellows faces the inlet end of the fluid passage; a gas chamber is arranged at the rear end of the bellows for connecting the inner cavity of the bellows, a gas cylinder is arranged in the gas chamber through a cylinder seat, and the end of the cylinder rod of the gas cylinder is connected to the inner wall of the extension end of the bellows; an air inlet for introducing gas into the gas cylinder and two on-off control valves for controlling whether to introduce gas into the gas cylinder are arranged on the side wall of the valve body.

[0006] Further optimization of the technical solutions, the valve body comprises a front valve body for connecting the connecting flange at the front end and the extension end of the bellows to form the inlet of the fluid passage, a middle valve body for connecting the external compressor to introduce gas into the gas cylinder, and a rear valve body for connecting the connecting flange at the rear end to form the outlet of the fluid passage.

[0007] Further optimization of the technical solutions, the inlet end of the fluid passage in the front valve body is provided with a mesh-shaped diaphragm for filtering impurities in the fluid.

[0008] Further optimization of the technical solutions, the air inlet and the on-off control valve are arranged on the middle valve body.

[0009] Further optimization technical scheme, the rear end of the gas chamber is provided with a cylinder cover for sealing the gas chamber through bolts.

[0010] Further optimization technical scheme, the middle valve body is provided with O-shaped sealing ring for improving sealing performance between the middle valve body and the rear valve body and the cylinder seat, the rear valve body and the connecting flange, and the cylinder cover and the gas chamber.

[0011] Further optimization technical scheme, the switch control valve is provided with O-shaped sealing ring for improving sealing performance between the switch control valve and the middle valve body.

[0012] Further optimization technical scheme, the valve body, the bellows and the gas chamber are made of acid-resistant plastic PTFE.

[0013] Due to the adoption of the above technical scheme, the technical progress achieved by the present application is as follows.

[0014] The pneumatic valve device for small-diameter pipes provided by the present application realizes reliable control of liquid on-off by driving the deformation of the bellows through compressed air, and is widely applicable to precise conveying scenes of high-purity, corrosive or toxic chemicals, and realizes zero-leakage conveying of fluid due to its high sealing performance and fast response speed. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 is a structural schematic view of the present application; Figure 2 is an exploded view of the present application; Figure 3 is a structural schematic view of the mesh diaphragm of the present application; Figure 4 is an operating principle diagram of the pneumatic valve of the present application; Figure 5 is a working state diagram of the pneumatic valve when the switch control valve is closed; Figure 6 is a working state diagram of the pneumatic valve when the switch control valve is opened.

[0016] Wherein: 1. front locking, 2. front valve body, 3. middle valve body, 4. rear valve body, 5. rear locking, 6. connecting flange, 7. bellows, 8. cylinder, 9. cylinder seat, 10. cylinder cover, 11. mesh diaphragm, 12. O-shaped sealing ring, 13. switch control valve, 14. air inlet, 15. liquid tank. DETAILED DESCRIPTION

[0017] The present application will be further described in detail below in combination with the drawings and specific embodiments.

[0018] The pneumatic valve device for small-diameter pipes combines Figures 1 to 2As shown, the valve body is provided with a front locking 1 and a rear locking 5 at the front and rear ends thereof respectively, and a connecting flange 6 is arranged at each of the front and rear ends of the valve body for installing a pneumatic valve device, a fluid passage is arranged in the valve body and communicates with the front and rear connecting flanges, a bellows 7 is arranged in the fluid passage for opening and closing the fluid passage, and the extension end of the bellows 7 faces the inlet end of the fluid passage, and the opening and closing of the fluid passage are realized by the extension and contraction of the bellows.

[0019] The rear end of the bellows 7 is provided with a gas chamber communicating with the bellows, a cylinder 8 is arranged in the gas chamber through a cylinder seat 9, the end of the cylinder rod of the cylinder 8 is connected to the inner wall of the extension end of the bellows 7, and an air inlet 14 and two switch control valves 13 are arranged on the side wall of the valve body, the air inlet 14 is used for introducing gas into the cylinder, and the switch control valves 13 communicate with the air inlet 14 and are used for controlling whether to introduce gas into the cylinder. A cylinder cover 10 is arranged at the rear end of the gas chamber through bolts, and an O-shaped sealing ring 12 is arranged between the cylinder cover and the gas chamber for improving the sealing performance between the cylinder cover and the gas chamber.

[0020] The valve body comprises a front valve body 2, a middle valve body 3 and a rear valve body 4, the front valve body 2 communicates with the connecting flange 6 at the front end and forms the inlet of the fluid passage with the extension end of the bellows 7, and the inlet end of the fluid passage in the front valve body 2 is provided with a mesh-shaped diaphragm 11 for filtering impurities in the fluid.

[0021] The middle valve body 3 communicates with an external compressor and introduces gas into the cylinder through the air inlet 14, the air inlet 14 and the two switch control valves 13 are arranged on the middle valve body 3, the two switch control valves 13 are an opening gas valve and a closing gas valve, and whether to introduce gas into the cylinder is realized. O-shaped sealing rings 12 are arranged between the middle valve body and the rear valve body 4 and the cylinder seat 9 for improving the sealing performance of the valve, and O-shaped sealing rings 12 are arranged between the switch control valves and the middle valve body 3 for improving the sealing performance between the switch control valves and the valve body.

[0022] The rear valve body 4 communicates with the connecting flange 6 at the rear end and forms the outlet of the fluid passage, and O-shaped sealing rings 12 are arranged between the rear valve body 4 and the connecting flange 6 for improving the sealing performance of the valve body.

[0023] In order to improve the corrosion resistance of the valve, the valve body, the bellows 7 and the gas chamber are all made of acid-resistant plastic PTFE, and will not be eroded by acid liquid in the use process, and the application occasions are more widely.

[0024] The application principle diagram of the application is as follows Figure 4As shown, the front flange of the pneumatic valve device is connected with the liquid outlet end of the liquid tank 15, the liquid in the liquid tank is supplied to the pneumatic valve device through the connecting flange, the opening and closing of the pneumatic valve device is controlled by the switch control valve, the switch control valve is an external control valve, usually a manual or electromagnetic valve.

[0025] In the working process of the present application, when the switch control valve is closed, the working state diagram of the pneumatic valve is as shown in Figure 5 As shown, the liquid in the liquid tank flows into the pneumatic valve device through the connecting flange, since the switch control valve is closed, compressed air cannot enter the air chamber inside the pneumatic valve device, the bellows is in the state of internal shrinkage deformation, the blockage of the fluid passage is removed, at this time the liquid can flow into the downstream pipeline through the fluid passage inside the pneumatic valve device, the system is in the state of conduction.

[0026] When the switch control is opened, compressed air is injected into the air chamber of the pneumatic valve device through the air inlet, at this time the working state diagram of the pneumatic valve is as shown in Figure 6 As shown, the compressed air enters the cylinder, pushes the bellows to expand and deform forward, the bellows tightly abuts the fluid passage inlet of the front valve body to completely block the fluid passage, at this time the liquid cannot continue to pass, the system switches to the blocking state.

Claims

1. A pneumatic valve device for small-diameter pipes, characterized in that: The valve body includes a valve body with connecting flanges (6) for installing pneumatic valve devices at its front and rear ends respectively via a front locking (1) and a rear locking (5). The valve body has a fluid channel connecting the two connecting flanges inside. A bellows (7) for opening and closing the fluid channel is provided inside the fluid channel. The telescopic end of the bellows (7) faces the inlet end of the fluid channel. The rear end of the bellows (7) is provided with an air chamber that connects to the inner cavity of the bellows (7). A cylinder (8) is provided inside the air chamber via a cylinder seat (9). The end of the telescopic rod of the cylinder (8) is connected to the inner wall of the telescopic end of the bellows (7). The side wall of the valve body is provided with an air inlet (14) for introducing gas into the cylinder and two on / off control valves (13) that connect to the air inlet for controlling whether gas is introduced into the cylinder.

2. The pneumatic valve device for small-diameter pipes according to claim 1, characterized in that: The valve body includes a front valve body (2) that connects the front end of the connecting flange (6) and the telescopic end of the bellows (7) to form a fluid channel inlet, a middle valve body (3) that connects to an external compressor to introduce gas into the cylinder (8), and a rear valve body (4) that connects to the rear end of the connecting flange (6) to form a fluid channel outlet.

3. The pneumatic valve device for small-diameter pipes according to claim 2, characterized in that: The inlet end of the fluid channel inside the front valve body (2) is provided with a mesh diaphragm (11) for filtering impurities in the fluid.

4. The pneumatic valve device for small-diameter pipes according to claim 2, characterized in that: The air inlet (14) and the switch control valve (13) are both located on the valve body (3).

5. The pneumatic valve device for small-diameter pipes according to claim 1, characterized in that: The rear end of the air chamber is bolted with a cylinder head (10) for sealing the air chamber.

6. The pneumatic valve device for small-diameter pipes according to claim 5, characterized in that: O-rings (12) for improving sealing performance are provided between the middle valve body (3) and the rear valve body (4) and the cylinder seat (9), between the rear valve body (4) and the connecting flange (6), and between the cylinder head (10) and the air chamber.

7. The pneumatic valve device for small-diameter pipes according to claim 2, characterized in that: An O-ring (12) for improving sealing performance is provided between the switch control valve (13) and the valve body (3).

8. The pneumatic valve device for small-diameter pipes according to claim 1, characterized in that: The valve body, bellows (7) and air chamber are all made of acid-resistant plastic PTFE.

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