Pneumatic control valve

Abstract

The utility model belongs to the field of valves, and provides a pneumatic control valve which comprises a valve body, a support and a membrane cover which are sequentially connected from bottom to top, a sealing seat is arranged in the valve body, a membrane capable of moving up and down is arranged in the membrane cover, a valve rod is downwards arranged on the membrane, and the valve rod is connected with the support. The bottom of the valve rod sequentially penetrates into the valve body and the sealing seat and is provided with a sealing bowl matched with the sealing seat, the sealing seat comprises multiple layers of sealing rings which are arranged up and down, the outer walls of the sealing rings jointly form a circle of connecting block, a sleeve is formed in the sealing seat, the bottom of the valve rod penetrates into the sleeve and then is connected with the sealing bowl, and the sealing bowl is connected with the sealing seat. A matched pre-tightening spring is arranged on the valve rod and located between the sleeve and the sealing bowl. The pneumatic control valve aims to solve the problems that an existing pneumatic control valve is poor in sealing effect, and a sealing seat in the pneumatic control valve is single in function.

Description

Technical Field

[0001] The utility model belongs to the field of valves, and particularly relates to a pneumatic control valve. Background Art

[0002] The pneumatic control valve, also known as a pneumatic actuator, uses compressed gas as the power source to drive the valve to achieve on-off or proportional regulation. The characteristics of the pneumatic control valve are simple control, reliable action, fast response, stable performance, convenient maintenance, and intrinsically safe, without the need to take additional fire and explosion prevention measures. It is one of the industrial process control instruments widely used in industrial enterprises such as petroleum, chemical industry, electric power, and metallurgy.

[0003] With the development of the chemical industry, the types of pneumatic control valves are increasing. When most pneumatic control valves are closed, if the air pressure in the diaphragm cover is unstable, it cannot ensure that the sealing bowl can be pressed down stably and sealed on the sealing seat, resulting in poor sealing effect of the pneumatic control valve. And the existing sealing seat has a relatively single function, such as it cannot play a good guiding role during the process of the valve stem driving the sealing bowl. Summary of the Utility Model

[0004] In view of the above problems, the purpose of the utility model is to provide a pneumatic control valve, aiming to solve the problems of poor sealing effect of the existing pneumatic control valve and the single function of the sealing seat therein.

[0005] The utility model adopts the following technical scheme: The control valve includes a valve body, a bracket, and a diaphragm cover connected in sequence from bottom to top. A sealing seat is arranged in the valve body. A diaphragm that can move up and down is arranged in the diaphragm cover. A valve stem is arranged downward from the diaphragm. The bottom of the valve stem penetrates through the valve body and the sealing seat in sequence and is provided with a sealing bowl that matches the sealing seat. The sealing seat includes multiple sealing rings arranged up and down. A connecting block is formed in a circle on the outer walls of the sealing rings. A sleeve is formed in the sealing seat. After the bottom of the valve stem penetrates into the sleeve, it is connected to the sealing bowl. A pre-tightening spring that matches is arranged on the valve stem between the sleeve and the sealing bowl.

[0006] Further, a linkage block is arranged on the valve stem. A guiding block and a measuring block are respectively arranged on the inner side of the bracket. A guiding opening is formed on one side of the linkage block corresponding to the guiding block. A pointer is formed on the other side of the linkage block, and the pointer points to the measuring block.

[0007] Further, an adjusting spring is arranged above the diaphragm in the diaphragm cover. An air port is opened at the bottom of the diaphragm cover.

[0008] Further, a dust-proof sleeve is arranged on the valve stem between the linkage block and the diaphragm cover.

[0009] Further, a gland is provided inside and at the top of the membrane cover, and a screw rod is screwed into the top of the membrane cover, and the bottom of the screw rod is connected to the gland.

[0010] Further, a lifting ring is provided at the top of the screw rod.

[0011] The beneficial effects of the present utility model are as follows: The sealing seat includes three sealing rings arranged up and down. Under the action of a circle of connecting blocks, the overall sealing bowl can be more stable and firm. And when the sealing bowl falls off the sealing seat, at this time, the liquid in the valve body flows in from the gap between adjacent connecting blocks and flows out from the water outlet of the valve body, and does not hinder the flow of the liquid.

[0012] In addition, the sealing seat serves as the installation carrier of the sleeve. The sleeve can play a role in limiting and guiding the valve stem, making the valve stem move more stably up and down. At the same time, the sleeve also plays a role in limiting the pre-tightening spring. Description of the Drawings

[0013] Figure 1 is a cross-sectional view of a pneumatic control valve provided by the present utility model.

[0014] Figure 2 is an overall view of a pneumatic control valve provided by the present utility model.

[0015] Figure 3 is a cross-sectional view of the sealing seat provided by the present utility model.

[0016] Figure 4 is a schematic overall view of the sealing seat provided by the present utility model. Detailed Embodiments

[0017] In order to make the patent purpose, technical solutions and advantages of the present utility model clearer, the following further describes the present utility model in detail with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model.

[0018] In order to illustrate the technical solutions described in the present utility model, the following will be described through specific embodiments.

[0019] For the convenience of description, only parts related to the embodiments of the present utility model are shown.

[0020] Combined with Figures 1-4As shown, the regulating valve includes a valve body 1, a bracket 2, and a diaphragm cover 3 connected in sequence from bottom to top. A sealing seat 4 is provided inside the valve body 1. A diaphragm 11 that can move up and down is provided inside the diaphragm cover 3. A valve stem 6 is provided downward on the diaphragm 11. The bottom of the valve stem 6 penetrates through the valve body 1 and the sealing seat 4 in sequence and is provided with a sealing bowl 7 that matches the sealing seat 4. The sealing seat 4 includes multiple sealing rings 41 arranged up and down. A connecting block 42 is formed jointly on the outer walls of the sealing rings 41. A sleeve 43 is formed inside the sealing seat. After the bottom of the valve stem 6 penetrates into the sleeve 43, it is connected to the sealing bowl 7. A matching pre-tightening spring 8 is provided on the valve stem 6 and between the sleeve 43 and the sealing bowl 7.

[0021] In this structure, as Figure 1 , water inlets 9 and outlets 10 are respectively opened at the front and rear positions of the valve body. A diaphragm 11 is provided inside the diaphragm cover 3. The diaphragm divides the diaphragm cover into upper and lower air chambers from top to bottom. An adjusting spring 12 is provided above the diaphragm 11 inside the diaphragm cover 3. An air port 13 is opened at the bottom of the diaphragm cover 3. The air port is connected to a pneumatic diaphragm pump through a hose. And the pneumatic diaphragm pump is not the key content of this device, so it will not be described in detail here.

[0022] In specific working applications, when it is necessary to open the regulating valve to open the pipeline system, first, the pneumatic diaphragm pump starts to work and inflates the lower air chamber through the hose. During the inflation process, the air pressure in the air chamber increases, and the diaphragm is gradually pushed upward under pressure towards the upper air chamber. At the same time, the diaphragm drives the valve stem to move upward. When the valve stem moves, the adjusting spring and the pre-tightening spring arranged up and down are gradually compressed until the sealing bowl detaches from the sealing seat. At this time, the regulating valve is opened.

[0023] When it is necessary to close the regulating valve, the pneumatic diaphragm pump sucks air, the diaphragm moves downward, and the above two springs recover their deformation. Under the suction of the pneumatic diaphragm pump and the pre-tightening action of the above two springs, the sealing bowl firmly presses on the sealing seat. At this time, the regulating valve is closed.

[0024] In this embodiment, the sealing seat includes three sealing rings arranged up and down. Under the action of the connecting block in a circle, the overall sealing bowl can be more stable and firm. And when the sealing bowl detaches from the sealing seat, the liquid inside the valve body flows in from the gap between adjacent connecting blocks and flows out from the outlet of the valve body, without hindering the flow of the liquid.

[0025] In addition, the sealing seat serves as the installation carrier of the sleeve. The sleeve can play a role in limiting and guiding the valve stem, making the valve stem move more stably when moving up and down. At the same time, the sleeve also plays a role in limiting the pre-tightening spring.

[0026] As a preferred structure, combined with Figure 2, a linkage block 21 is provided on the valve stem 6, and a guide block 14 and a metering block 15 are respectively provided inside the bracket 2. A guide opening 22 is formed on one side of the linkage block 21 corresponding to the guide block 14, and the guide block is located within the guide opening. A pointer 16 is formed on the other side of the linkage block 21, and the pointer 16 points to the metering block 15.

[0027] Scales are formed on the metering block. When the valve stem moves up and down, the linkage block moves up and down accordingly. Specifically: when the linkage block moves up and down, the guide block moves within the guide opening, making the entire moving process more stable. In addition, the pointer moves up and down along the metering block, and the precise control of the valve opening can be achieved by observing the scale value pointed by the tip of the pointer.

[0028] A dust cover 17 is provided on the valve stem 6 and between the linkage block 21 and the diaphragm cover 3. The dust cover is made of soft material. When the valve stem moves upward, the dust cover is compressed under the extrusion of the linkage block. Under the action of the dust cover, dust and other impurities can be greatly reduced from entering the diaphragm cover.

[0029] Further, as a preferred structure, Figure 1 , a gland 18 is provided at the top inside the diaphragm cover 3, and a screw rod 19 is screwed into the top of the diaphragm cover 18. The bottom of the screw rod 19 is connected to the gland 18. A lifting ring 20 is provided at the top of the screw rod.

[0030] In this structure, the pre-tightening force of the gland of the adjusting spring can be finely adjusted by adjusting the installation position of the gland. During specific adjustment, the screw rod can be rotated up and down by turning the lifting ring, so as to drive the gland to move up and down. At the same time, the regulating valve can also be lifted by the lifting ring.

[0031] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A pneumatic regulating valve, characterized in that: The regulating valve includes a valve body, a bracket and a diaphragm cover which are connected in sequence from bottom to top, a sealing seat is provided in the valve body, a diaphragm which can move up and down is provided in the diaphragm cover, a valve stem is provided downwardly on the diaphragm, the bottom of the valve stem penetrates into the valve body and the sealing seat in sequence and is provided with a sealing bowl which matches the sealing seat, the sealing seat includes a plurality of sealing rings which are arranged up and down, the outer walls of the sealing rings jointly form a circle of connecting blocks, a sleeve is formed in the sealing seat, the bottom of the valve stem penetrates into the sleeve and is connected to the sealing bowl, a matching preload spring is provided on the valve stem and between the sleeve and the sealing bowl.

2. A pneumatic control valve as claimed in claim 1, characterized in that: The valve stem is provided with a linkage block, and the inner side of the bracket is provided with a guide block and a metering block respectively. A guide opening is opened on one side of the linkage block corresponding to the guide block, and a pointer is formed on the other side of the linkage block, and the pointer points to the metering block.

3. A pneumatic control valve as claimed in claim 2, characterized in that: An adjusting spring is arranged inside the membrane cover and above the membrane, and an air port is opened at the bottom of the membrane cover.

4. A pneumatic regulating valve as claimed in claim 3, characterized in that: A dust cover is provided on the valve stem and between the linkage block and the membrane cover.

5. A pneumatic regulating valve as claimed in claim 4, characterized in that: A pressure cap is arranged inside the membrane cover and at the top, a screw is screwed into the top of the membrane cover, and the bottom of the screw is connected to the pressure cap.

6. A pneumatic regulating valve as claimed in claim 5, characterized in that: A lifting ring is provided on the top of the screw.

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