A capillary channel gas micro-flow regulating valve

Abstract

The present invention discloses a capillary channel gas micro-flow regulating valve, belonging to the technical field of flow regulating valves, which comprises a valve body, a valve core, a valve cover and a hand wheel. The valve core is cooperatively connected with the valve body, the valve cover is fixed on the valve body. The cylindrical surface of the valve core includes a capillary groove part, an integral groove part and a sealing part. A plurality of parallel capillary grooves are circumferentially formed on the cylindrical surface of the valve core. The inner cylindrical surface of the valve body cooperates with the outer cylindrical surface of the valve core to form a plurality of parallel capillary channels. The ends of the capillary channels are open and communicate with the integral groove part, and the integral groove part communicates with the outlet flow channel of the valve body. When the valve works, the air flow enters from one side of the valve, flows through the capillary channels and then flows out from the other side of the valve. By rotating the hand wheel, the length and number of the capillary channels in the working state can be changed, thereby changing the gas flow rate flowing through the valve. The regulating characteristics of the regulating valve in the small opening and large opening ranges can vary greatly, and it has the characteristics of a large flow regulation range and stable and reliable regulating performance.

Description

Technical Field

[0001] The present invention relates to the technical field of flow control valves, and particularly to a capillary channel micro gas flow control valve. Background Art

[0002] Micro gas flow control valves are widely used in fields such as semiconductors, pharmaceuticals, and chemicals. The working principle of existing flow control valves generally changes the flow area of the valve port by changing the position of the valve core, thereby changing the flow rate. For micro flow control valves, the valve port size is small and the effective adjustment distance is short, and there are generally problems such as a narrow effective adjustment range, a large return deviation, and non-linear adjustment.

[0003] According to different driving methods, control valves can be divided into several categories such as manual, electric, and pneumatic. In the flow automatic control system, electric control valves are used more frequently. Since the flow rate is related not only to the valve opening but also to factors such as the physical properties of the fluid medium and the driving differential pressure, feedback control is generally required for flow regulation. Due to the above-mentioned deficiencies of existing micro flow control valves, such as a narrow adjustment range and a large return deviation, it is not easy to achieve stable and reliable flow regulation. Summary of the Invention

[0004] In order to solve the above problems existing in the prior art, the present invention provides a capillary channel micro gas flow control valve.

[0005] The technical solution of the present invention is as follows: A capillary channel micro gas flow control valve includes a valve body, a valve core, a valve cover, and a handwheel. The valve core is cooperatively connected with the valve body, and the valve cover is fixed on the valve body. The inner side of the valve body is a cylindrical surface, and the axis of the cylindrical surface is perpendicular to the axis of the valve. The inlet and outlet flow channels are long strips at the cylindrical surface. The valve core is a cylinder, and the cylindrical surface of the valve core includes a capillary groove part, an integral groove part, and a sealing part. A plurality of parallel capillary grooves are circumferentially formed on the cylindrical surface of the valve core. The inner cylindrical surface of the valve body cooperates with the outer cylindrical surface of the valve core to form a plurality of parallel capillary channels. The ends of the capillary channels are open and communicate with the integral groove part, and the integral groove part communicates with the outlet flow channel of the valve body.

[0006] The length of the integral groove of the valve core is 1 / 2 of the circumference of the valve core cylindrical surface, and the depth is 2-6 times that of the capillary groove.

[0007] The length of the sealing part of the cylindrical surface of the valve core is 1 / 12 of the total circumference of the cylindrical surface, and this length is greater than the width of the opening of the inlet flow channel of the valve body at the cylindrical surface.

[0008] The lengths of the capillary grooves on the valve core are different and are arranged in order of length. The longest does not exceed 5 / 12 of the valve core cylindrical surface, and the shortest is approximately 1 / 4 of the circumference of the valve core cylindrical surface. The depth and width of the capillary grooves are equivalent, the ends of the capillary grooves are flush, and are connected to the integral groove.

[0009] The ends of the capillary grooves on the valve core are in a gradually expanding shape.

[0010] A sealing groove is formed in the sealing part of the valve core, and a sealing strip is installed in the sealing groove. The sealing strip is in close contact with the inner cylindrical surface of the valve body.

[0011] The valve cover is fixed on the valve body by bolts. A sealing packing is provided between the valve cover and the valve core, and the valve cover presses the sealing packing tightly.

[0012] A conical pit is provided at the center of the inner bottom surface of the valve body, and a conical protrusion is provided at the center of the bottom of the valve core. The conical pit and the conical protrusion cooperate with each other.

[0013] A handwheel is provided at the top of the valve core.

[0014] The beneficial effects of the present invention are as follows:

[0015] 1) By changing the length and number of capillary channels to change the valve impedance, as the valve opening increases, the length of the capillary channels decreases and the number increases, and the valve impedance decreases, enabling wide-range flow regulation.

[0016] 2) In the small opening stage, the number of connected capillary channels is small and the valve impedance is large. When the number remains unchanged, the flow rate is inversely proportional to the opening, and precise regulation can be achieved at small openings.

[0017] 3) The total stroke of the valve does not exceed 1 / 2 week, the relationship between the opening and the rotation angle is simple and clear, and the valve opening has good repeatability. Description of the Drawings

[0018] Figure 1 is a schematic structural diagram of the present invention;

[0019] Figure 2 is a schematic sectional structural diagram of the present invention;

[0020] Figure 3 is a schematic structural diagram of the valve body;

[0021] Figure 4 is a schematic structural diagram of the valve body;

[0022] Figure 5 is a schematic structural diagram of the valve core;

[0023] Figure 6 is a schematic structural diagram of the valve core in the A direction;

[0024] Figure 7 is a schematic sectional structural diagram of the valve core in the B-B direction;

[0025] Figure 8 is an unfolded plan view of the cylindrical surface of the valve core;

[0026] In the figure: 1 - valve body; 2 - valve core; 3 - valve cover; 4 - handwheel; 5 - bolt; 6 - sealing packing; 7 - sealing strip; 8 - conical protrusion; 9 - capillary groove part; 10 - integral groove part; 11 - sealing part; 12 - capillary groove; 13 - integral groove; 14 - sealing groove; 15 - gradually expanding groove; 16 - conical protrusion. Detailed implementation mode

[0027] The present invention will be further described below in conjunction with the accompanying drawings.

[0028] As Figure 1-4 shown, a capillary channel gas micro - flow regulating valve includes a valve body 1, a valve core 2, a valve cover 3, a handwheel 4, bolts 5, a sealing packing 6 and a sealing strip 7. The valve core 2 is cooperatively connected with the valve body 1, the valve cover 3 is fixed on the valve body 1, the handwheel 4 is arranged at the top of the valve core 2, the valve cover 3 is fixed on the valve body 1 through bolts 5, a sealing packing 6 is arranged between the valve cover 3 and the valve core 2, and the valve cover 3 presses the sealing packing 6 to achieve a sealing effect.

[0029] As Figure 5-8 shown, the inner side of the valve body 1 is a cylindrical surface, the axis of the cylindrical surface is perpendicular to the axis of the valve, and the inlet and outlet flow channels are strip - shaped at the cylindrical surface. The valve core 2 is a cylinder, and the cylindrical surface of the valve core 2 includes a capillary groove part 9, an integral groove part 10 and a sealing part 11. A plurality of parallel capillary grooves 12 are circumferentially opened on the cylindrical surface of the valve core 2. The inner cylindrical surface of the valve body 1 cooperates with the outer cylindrical surface of the valve core 2 to form a plurality of parallel capillary channels. The ends of the capillary channels are open and communicate with the integral groove part 10, and the integral groove part 10 communicates with the outlet flow channel of the valve body 1.

[0030] The length of the integral groove of the valve core 2 is 1 / 2 week of the cylindrical surface of the valve core, and the depth is 2 - 6 times that of the capillary groove 12.

[0031] The length of the sealing part 11 of the cylindrical surface of the valve core is about 1 / 12 of the total circumference of the cylindrical surface. This length needs to be greater than the width of the opening of the inlet flow channel of the valve body at the cylindrical surface to ensure complete sealing. A sealing groove 14 is longitudinally opened along the cylindrical surface of the sealing part 11 of the cylindrical surface of the valve core, and a sealing strip 7 is placed in the sealing groove 14. After the valve is assembled, the sealing strip 7 is in close contact with the inner cylindrical surface of the valve body to prevent the air flow from directly entering the integral groove 13 without passing through the capillary channels, causing internal leakage of the valve. The lengths of the capillary grooves 12 on the valve core 2 are different and are arranged in order of length. The longest does not exceed 5 / 12 of the cylindrical surface of the valve core, and the shortest is about 1 / 4 of the circumference of the cylindrical surface of the valve core. The depth and width of the capillary groove 12 are equivalent, and the end of the capillary groove is in a gradually expanding shape, with the end being flush and communicating with the integral groove. The length of the integral groove part 10 is 1 / 2 week of the cylindrical surface of the valve core, and the depth gradually increases from front to back and is 2 - 6 times the depth of the capillary groove 12.

[0032] At the center of the inner bottom surface of the valve body 1, there is a conical concave pit, and at the center of the bottom of the valve core 2, there is a conical protrusion 16. The conical concave pit and the conical protrusion 16 cooperate with each other, and the cooperation between the two reduces the friction between the bottom of the valve core and the valve body when the valve core rotates.

[0033] Rotating the handwheel 4 can change the length and number of capillary channels in the working state. The rotation range of the valve core 2 is about 1 / 2 week. By rotating the handwheel 4 to adjust the relative position of the valve core 2 and the valve body 1, the valve can be in the off or connected state. That is, when the sealing part of the valve core 2 is at the opening position of the inlet flow channel of the valve body, the valve is turned off, and when the capillary groove part of the valve core 2 is located at the opening position of the inlet flow channel of the valve body 1, the valve is in the connected state. The total stroke of the valve does not exceed 1 / 2 week, the relationship between the opening and the rotation angle is simple and clear, and the valve opening repeatability is good.

[0034] When the valve is working, the air flow enters from one side of the valve, flows through the capillary channels, and then flows out from the other side of the valve. Rotating the handwheel 4 can change the length and number of capillary channels in the working state, thereby changing the gas flow rate flowing through the valve. When the valve is working, as the valve opening increases, the capillary channels are sequentially turned on from long to short, and the working section length of the capillary channels also gradually becomes shorter. The flow impedance of the valve decreases, and the flow capacity increases, thereby achieving the effect of flow regulation. In the small opening stage, the number of capillary channels turned on is small, and the valve impedance is large. When the number remains unchanged, the flow rate is inversely proportional to the opening. Precise regulation can be achieved at small openings. The adjustment characteristics of this regulating valve in the small opening and large opening ranges can vary greatly, and it has the characteristics of a large flow regulation range and stable and reliable regulation performance.

[0035] Analyze the valve characteristics based on the laminar flow in the capillary channels:

[0036] When the valve opening is x, the flow rate flowing through the valve:

[0037]

[0038] In the formula, n is the number of capillary channels; d is the diameter of the capillary channels; l max is the maximum length of the capillary channels (when the opening x = 0); x is the opening, defined as the axial length rotated by the valve core; μ is the dynamic viscosity of the fluid.

[0039] At the maximum opening,

[0040]

[0041] In the formula, l min is the length of the capillary channels when the valve opening is the largest.

[0042] When the number of capillary channels remains unchanged,

[0043]

[0044]

[0045] In the formula, X is the maximum opening degree.

[0046] Formula (4) indicates that the change in the relative opening degree of the valve causing the change in the relative flow rate is not in a direct proportional relationship with the relative flow rate at this point, that is, it is not an equal percentage type regulating valve. As the valve opening x increases, the relative flow rate changes faster. And when the number of capillary channels changes, that is, as the valve opening increases, the number of capillary channels also increases, then the flow rate changes even faster. Therefore, the regulating valve of the present invention can be designed with the following characteristics: at a small opening degree, the valve characteristic is close to the equal percentage type, and in the large opening degree range, the change of this regulating valve is faster than that of the equal percentage regulating valve.

[0047] The above is only the basic idea and method of the present invention, and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the idea and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A capillary channel gas micro-flow regulating valve, comprising a valve body (1), a valve core (2) and a valve cover (3), wherein the valve core (2) is cooperatively connected with the valve body (1), and the valve cover (3) is fixed on the valve body (1). It is characterized in that: The inner side of the valve body (1) is a cylindrical surface, the axis of the cylindrical surface is perpendicular to the axis of the valve, and the inlet and outlet channels are strip-shaped at the cylindrical surface. The valve core (2) is a cylinder, and the cylindrical surface of the valve core (2) includes a capillary groove part (9), an integral groove part (10) and a sealing part (11). A plurality of parallel capillary grooves (12) are circumferentially formed on the cylindrical surface of the valve core (2). The inner cylindrical surface of the valve body (1) cooperates with the outer cylindrical surface of the valve core (2) to form a plurality of parallel capillary channels. The ends of the capillary channels are open and communicate with the integral groove part (10), and the integral groove part (10) communicates with the outlet channel of the valve body (1). The length of the integral groove part of the valve core (2) is 1 / 2 of the circumference of the valve core cylindrical surface, and the depth is 2-6 times that of the capillary groove (12). The length of the sealing part (11) of the valve core cylindrical surface is 1 / 12 of the total circumference of the cylindrical surface, and this length is greater than the width of the opening of the inlet channel of the valve body at the cylindrical surface. The lengths of the capillary grooves (12) on the valve core (2) are different and are arranged in order of length, the longest not exceeding 5 / 12 of the valve core cylindrical surface, and the shortest being 1 / 4 of the circumference of the valve core cylindrical surface. The depth and width of the capillary groove (12) are equivalent, the ends of the capillary grooves (12) are flush and are connected to the integral groove (13).

2. A capillary channel gas micro-flow regulating valve according to claim 1, It is characterized in that: The ends of the capillary grooves (12) on the valve core (2) are in a gradually expanding shape.

3. A capillary channel gas micro-flow regulating valve according to claim 1, It is characterized in that: A sealing groove (14) is formed in the sealing part of the valve core (2), and a sealing strip (7) is installed in the sealing groove (14), and the sealing strip (7) is in close contact with the inner cylindrical surface of the valve body (1).

4. A capillary channel gas micro-flow regulating valve according to claim 1, It is characterized in that: The valve cover (3) is fixed on the valve body (1) by bolts (5), a sealing packing (6) is provided between the valve cover (3) and the valve core (2), and the valve cover (3) presses the sealing packing (6).

5. A capillary channel gas micro-flow regulating valve according to claim 1, It is characterized in that: A conical pit is provided at the center of the inner bottom surface of the valve body (1), and a conical protrusion (16) is provided at the center of the bottom of the valve core (2), and the conical pit cooperates with the conical protrusion (16).

6. A capillary channel gas micro-flow regulating valve according to claim 1, It is characterized in that: A handwheel (4) is provided at the top of the valve core (2).

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