A direct-acting voltage regulator for compensating spring effect

Abstract

The present invention relates to a direct-acting pressure regulator for compensating spring effect, comprising a main valve body and a driving assembly, wherein the main valve body is mounted at the lower end of the driving assembly, a valve seat, a valve disc, a valve stem, a valve stem sleeve and a balancing diaphragm are assembled in the main valve body, and the driving assembly comprises an upper diaphragm shell and a lower diaphragm shell, a diaphragm and a tray. The outer peripheral wall of the tray and the inner peripheral wall of the lower half of the upper diaphragm shell form an annular installation cavity with an inverted "eight"-shaped cross section, the diaphragm forms an annular protrusion with an Ω-shaped cross section upward in the annular installation cavity, and a signal tube is connected to the lower diaphragm shell, and the signal tube is used to communicate with a pipeline connected to the outlet end of the main valve body. The present invention transforms the traditional direct-acting pressure regulator, and when the diaphragm and the tray move from bottom to top after being subjected to force, the effective area of ​​the diaphragm gradually increases; when the diaphragm and the tray move from top to bottom after being subjected to force, the effective area of ​​the diaphragm gradually decreases, so that the spring effect of the pressure regulator can be effectively compensated, and the pressure regulator can achieve a very high pressure stabilization accuracy.

Description

Technical Field

[0001] The invention relates to the field of gas pressure regulating devices, and in particular to a direct-acting pressure regulator for compensating spring effect. Background Art

[0002] A pressure regulator is a special valve on a pipeline that automatically adjusts the outlet pressure to stabilize it within a certain pressure range. Pressure regulators are divided into direct-acting pressure regulators and indirect-acting pressure regulators. The working principle of a direct-acting pressure regulator is to use the outlet pressure change of the pressure regulator to directly control the drive component to drive the regulating element to move. The main component of the drive component is the diaphragm. There is a pressure regulating spring inside the pressure regulator. When working, the pressure regulating spring will change the compression amount with the size of the valve disc opening. Therefore, the spring force changes with the valve disc opening. This change affects the pressure stabilization accuracy. The effect of this spring force change on the outlet pressure P2 of the pressure regulator is called the "spring effect".

[0003] A high-quality voltage regulator needs to minimize the spring effect as much as possible. There are roughly the following methods to reduce the spring effect in the existing technology: 1. Reduce the spring stiffness of the voltage regulating spring. This method can appropriately reduce the spring effect, but the adjustment range of the spring will be reduced; 2. The main diaphragm adopts rolling diaphragm technology, but the effect is not great; 3. The built-in signal tube method, also called the negative pressure method, the port of the signal tube must be placed in the pressure field in the outlet cavity of the voltage regulator, at a lower pressure position. This pressure must be less than the actual outlet pressure. The feedback pressure under the main diaphragm becomes smaller, causing the diaphragm to move downward, the valve disc opening becomes larger, and the outlet pressure of the voltage regulator becomes larger, so as to achieve the purpose of compensating for the spring effect. However, the pressure field of the outlet cavity inside the valve body is relatively complex and disordered, so it is difficult to find a suitable position for the signal tube port. If the signal tube is installed in an improper position, it will not play a role in compensating for the spring effect. Therefore, a large number of experiments are required, and even the structure of the valve body must be changed to achieve good results. Summary of the invention

[0004] The present invention effectively compensates for the spring effect of the voltage regulator from the perspective of changing the effective force-bearing area of ​​the diaphragm, thereby improving the voltage stabilization accuracy of the voltage regulator.

[0005] In order to solve the above problems existing in the prior art, the present invention provides a direct-acting pressure regulator for compensating spring effect, including a main valve body and a drive assembly, wherein the main valve body is installed at the lower end of the drive assembly, and a valve seat, a valve disc, a valve stem, a valve stem sleeve and a balancing diaphragm are assembled in the main valve body, the valve stem sleeve is fixed at the upper end of the main valve body, the valve stem is arranged in the valve stem sleeve, the valve disc is fixed at the lower end of the valve stem, the valve disc is located at the lower side of the valve seat, and the balancing diaphragm is installed on the upper side of the valve stem sleeve, the drive assembly includes an upper diaphragm shell and a lower diaphragm shell, a diaphragm and a tray, the diaphragm is fixed between the upper diaphragm shell and the lower diaphragm shell, the tray is arranged on the diaphragm, the lower diaphragm shell is fixed at the upper end of the main valve body, and the The upper end of the valve stem passes through the valve seat, the valve stem sleeve, the balancing diaphragm, the lower diaphragm shell and the diaphragm from bottom to top and is fixedly connected to the tray; a pressure-regulating spring is installed on the upper end of the tray; the pressure-regulating spring is located in the cavity of the upper diaphragm shell; a spring seat is fixed to the upper end of the pressure-regulating spring; an adjusting bolt is screwed on the upper end of the upper diaphragm shell; the lower end of the adjusting bolt passes through the upper diaphragm shell and is pressed against the spring seat; the outer peripheral wall of the tray and the inner peripheral wall of the lower half of the upper diaphragm shell form an annular installation cavity with an inverted "eight"-shaped cross-section; the diaphragm forms an annular protrusion with an Ω-shaped cross-section upward in the annular installation cavity; a signal tube is connected to the lower diaphragm shell; the signal tube is used to communicate with a pipeline connected to the outlet end of the main valve body.

[0006] Furthermore, the present invention provides a direct-acting voltage regulator for compensating for a spring effect, wherein the tray is an outer cone that is small at the top and large at the bottom, and the bottom surface of the tray and its outer side wall are smoothly transitioned through an arc.

[0007] Furthermore, the present invention provides a direct-acting voltage regulator for compensating spring effect, wherein the inner cavity of the lower half of the upper membrane shell is an inner conical cavity that is larger at the top and smaller at the bottom, and the bottom surface of the upper membrane shell and the inner side wall of its lower half are smoothly transitioned through a circular arc.

[0008] Furthermore, the present invention provides a direct-acting voltage regulator for compensating for a spring effect, wherein the angle between the generatrix of the outer side wall of the tray and the axis is 15° to 45°.

[0009] Furthermore, the present invention provides a direct-acting voltage regulator for compensating spring effect, wherein the angle between the generatrix of the inner conical cavity of the upper membrane shell 21 and the axis is the same as the angle between the generatrix of the outer wall of the tray 24 and the axis.

[0010] Compared with the prior art, the direct-acting pressure regulator of the present invention for compensating spring effect has the following advantages: the pressure-taking port of the signal tube is arranged outside the main valve body, one end of the signal tube is connected to the lower diaphragm shell, and the other end is connected to the pipeline connected to the outlet end of the main valve body, so as to provide feedback pressure for the diaphragm, the outer peripheral wall of the tray and the inner peripheral wall of the lower half of the upper diaphragm shell form an inverted "eight"-shaped annular installation cavity, and the diaphragm forms an annular protrusion with an Ω-shaped cross section upward in the annular installation cavity, and the annular protrusion of the diaphragm is in rolling contact with the outer wall of the tray. When the diaphragm moves upward, the spring force increases, and the effective area of ​​the diaphragm also increases. Similarly, when the diaphragm moves downward, the pressure regulating spring becomes loose, the spring force decreases, and the effective area of ​​the diaphragm also decreases. In summary, the effective area of ​​the diaphragm and the spring force are quantities that change in the same direction, and change with the change of the spring force, so the opening of the valve seat is affected very little, thereby enabling the pressure regulator to achieve a very high pressure stabilization accuracy.

[0011] The following is a further detailed description of a direct-acting voltage regulator for compensating spring effect of the present invention in conjunction with the specific embodiments shown in the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the structure of a voltage regulator in the prior art;

[0013] Figure 2 for Figure 1 A schematic diagram of the structure of a direct-acting voltage regulator for compensating spring effect;

[0014] Figure 3 Schematic diagram of the equivalent structure of the valve seat and the valve disc in the invention when the opening is small;

[0015] Figure 4 It is a schematic diagram of the equivalent structure of the valve seat and the valve disc in the present invention when the opening degree is relatively large. DETAILED DESCRIPTION

[0016] like Figure 1As shown, the pressure regulator structure in the prior art includes: a main valve body 1 and a drive assembly 2, the main valve body 1 is installed at the lower end of the drive assembly 2, and a valve seat 11, a valve disc 12, a valve stem 13, a valve stem sleeve 14 and a balancing diaphragm 15 are assembled in the main valve body 1, the valve stem sleeve 14 is fixed to the upper end of the main valve body 1, the valve stem 13 is arranged in the valve stem sleeve 14, the valve disc 12 is fixed to the lower end of the valve stem 13, the valve disc 12 is located at the lower side of the valve seat 11, and the balancing diaphragm 15 is installed on the upper side of the valve stem sleeve 14. The balancing diaphragm 15 is provided to improve the unbalanced force of the valve core, so that the outlet pressure can be unaffected by the change of the inlet pressure to a certain extent, thereby improving the pressure stabilization accuracy. The drive assembly 2 includes an upper membrane shell 21 and a lower membrane shell 22, a diaphragm 23 and a tray 24. The diaphragm 23 is fixed between the upper membrane shell 21 and the lower membrane shell 22. The tray 24 is arranged on the diaphragm 23. The lower membrane shell 22 is fixed to the upper end of the main valve body 1. The upper end of the valve stem 13 passes through the valve seat 11, the valve stem sleeve 14, the balancing diaphragm 15, the lower membrane shell 22 and the diaphragm 23 from bottom to top and is fixedly connected to the tray 24. A pressure regulating spring 25 is installed on the upper end of the tray 24. The pressure regulating spring 25 is located in the cavity of the upper membrane shell 21. A spring seat 26 is fixed to the upper end of the pressure regulating spring 25. An adjusting bolt 27 is screwed on the upper end of the upper membrane shell 21. The lower end of the adjusting bolt 27 passes through the upper membrane shell 21 and presses on the spring seat 26. The force of the pressure regulating spring 25 is changed by adjusting the bolt 27, thereby changing the outlet pressure of the pressure regulator.

[0017] According to the pressure regulation equation of the direct-acting voltage regulator, see formula 1.

[0018]

[0019] Where: P2 – regulator outlet pressure,

[0020] F- Spring force of the pressure-adjusting spring,

[0021] A – effective area of ​​diaphragm.

[0022] In the prior art, when the diaphragm 23 moves upward, the tray 24 will squeeze the pressure regulating spring 25, increasing the spring force F. According to Formula 1, it can be seen that after the spring force F increases, if the effective area A of the diaphragm 23 remains unchanged, the outlet pressure P2 of the pressure regulator will rise accordingly, and thus the outlet pressure P2 of the pressure regulator will lose stability. Similarly, when the diaphragm 23 moves downward, the pressure regulating spring 25 becomes loose, and the spring force F decreases. If the effective area A of the diaphragm remains unchanged, the outlet pressure P2 of the pressure regulator will decrease, and the outlet pressure P2 of the pressure regulator will also lose stability. The above phenomenon is called: spring effect.

[0023] like Figure 2As shown, in a specific embodiment of a direct-acting pressure regulator for compensating spring effect of the present invention, the outer peripheral wall of the tray 24 and the inner peripheral wall of the lower half of the upper membrane shell 21 form an annular installation cavity with an inverted "eight"-shaped cross-section, and the diaphragm 23 forms an annular protrusion with an Ω-shaped cross-section upward in the annular installation cavity. A signal tube 3 is connected to the lower membrane shell 22, and the signal tube 3 is used to communicate with a pipeline connected to the outlet end of the main valve body 1.

[0024] Specifically, the tray 24 is formed into an outer cone with a small top and a large bottom, and an arc is set between the bottom surface of the tray 24 and its outer side wall for smooth transition. The inner cavity of the lower half of the upper membrane shell 21 is set as an inner conical cavity with a large top and a small bottom, and an arc is set between the bottom surface of the upper membrane shell 21 and the inner side wall of the lower half for smooth transition. According to the change in the stiffness of the pressure regulating spring 25, the angle α between the generatrix of the outer wall of the tray 24 and the axis is selected in the range of 15° to 45°. The angle β between the generatrix of the inner conical cavity of the upper membrane shell 21 and the axis is set to be the same as the angle α, so as to ensure that the annular protrusion of the diaphragm 23 forms an effective rolling contact between the inclined surface of the outer wall of the tray 24 and the inclined surface of the inner conical cavity of the lower membrane shell 22.

[0025] In actual use, Figure 3 and Figure 4 As shown, Figure 3 is the position where the diaphragm 23 moves upward, Figure 4 It is the position where the diaphragm 23 moves downward. By comparison, it can be concluded that d2>d1, D2>D1, and the calculation formula for the effective area of ​​the diaphragm 23 is Assume that the effective area when the diaphragm 23 is displaced upward is A1, and the effective area when the diaphragm 23 is displaced downward is A2. By comparison, it is found that A1>A2, which proves that the effective area of ​​the diaphragm 23 increases when it moves upward, and decreases when it moves downward.

[0026] In summary, when the diaphragm 23 moves upward, the spring force F increases, and the effective area A of the diaphragm also increases; similarly, when the diaphragm moves downward, the pressure regulating spring 25 becomes loose, the spring force F decreases, and the effective area A of the diaphragm also decreases. In other words, the effective area of ​​the diaphragm 23 and the spring force change in the same direction and change with the change of the spring force, so the opening of the valve seat 11 is slightly affected, thereby enabling the pressure regulator to achieve a very high pressure stabilization accuracy.

[0027] It should be noted that the diaphragm in the present invention is made of a composite of rubber and silk fabric, which of course does not exclude the possibility of using diaphragms made of other rubber materials.

[0028] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] The above embodiments are only descriptions of the preferred implementation modes of the present invention, and are not intended to limit the scope of protection of the present invention. Without departing from the design concept of the present invention, various modifications made by those skilled in the art based on the technical solution of the present invention should all fall within the scope of protection determined by the claims of the present invention.

Claims

1. A direct-acting pressure regulator for compensating spring effect, comprising a main valve body (1) and a drive assembly (2), wherein the main valve body (1) is mounted at the lower end of the drive assembly (2), wherein a valve seat (11), a valve disc (12), a valve stem (13), a valve stem sleeve (14) and a balancing diaphragm (15) are assembled in the main valve body (1), wherein the valve stem sleeve (14) is fixed at the upper end of the main valve body (1), the valve stem (13) is arranged in the valve stem sleeve (14), the valve disc (12) is fixed at the lower end of the valve stem (13), the valve disc (12) is located at the lower side of the valve seat (11), the balancing diaphragm (15) is mounted at the upper side of the valve stem sleeve (14), and the drive assembly (2) comprises an upper diaphragm shell (21) and a lower diaphragm shell (22), a diaphragm (23) and a tray (24), wherein the diaphragm (23) is fixed at the upper The tray (24) is arranged on the diaphragm (23) between the membrane shell (21) and the lower membrane shell (22), the lower membrane shell (22) is fixed to the upper end of the main valve body (1), the upper end of the valve stem (13) passes through the valve seat (11), the valve stem sleeve (14), the balance diaphragm (15), the lower membrane shell (22) and the diaphragm (23) from bottom to top and is fixedly connected to the tray (24), the upper end of the tray (24) is installed with a pressure regulating spring (25), the pressure regulating spring (25) is located in the cavity of the upper membrane shell (21), the upper end of the pressure regulating spring (25) is fixed with a spring seat (26), the upper end of the upper membrane shell (21) is screwed with an adjusting bolt (27), the lower end of the adjusting bolt (27) passes through the upper membrane shell (21) and presses on the spring seat (26), characterized in that: The outer peripheral wall of the tray (24) and the inner peripheral wall of the lower half of the upper membrane shell (21) form an annular installation cavity with an inverted "eight"-shaped cross section. The diaphragm (23) forms an annular protrusion with an Ω-shaped cross section upwards in the annular installation cavity. The lower membrane shell (22) is connected to a signal tube (3), and the signal tube (3) is used to communicate with a pipeline connected to the outlet end of the main valve body (1). The tray (24) is an outer cone with a small top and a large bottom. The bottom surface of the tray (24) and its outer side wall are smoothly transitioned through an arc. The inner cavity of the lower half of the upper membrane shell (21) is an inner cone cavity with a large top and a small bottom. The bottom surface of the upper membrane shell (21) and its lower half inner side wall are smoothly transitioned through an arc. The included angle between the generatrix of the outer side wall of the tray (24) and the axis is 15° to 45°.

2. A direct-acting voltage regulator for compensating spring effect according to claim 1, characterized in that: The included angle between the generatrix of the inner conical cavity of the upper membrane shell (21) and the axis is the same as the included angle between the generatrix of the outer wall of the tray (24) and the axis.

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