A low flow resistance, low leakage shut-off valve

Abstract

This invention relates to a low-flow-resistance, low-leakage shut-off valve. The shut-off valve is a sleeve valve with end-face sealing. The sealing surface clamping force is provided by the pressure difference on the valve core and the variable elastic force components. The deformation directions of the multiple variable elastic force components are not parallel or coaxial with the movement direction of the valve core, but rather inclined. When the valve is closed, the angle between the deformation direction of the variable elastic force components and the valve core clamping direction is small, and the component of the elastic force in the valve core clamping direction is large, improving sealing performance and reducing leakage. When the valve is open, the variable elastic force components begin to oscillate with the valve core, and the component of the elastic force in the valve core clamping direction gradually decreases, which helps to increase the valve opening area and reduce flow resistance. Under the same opening force, the valve core balance position opening is larger, achieving lower flow resistance. A module with high elasticity can be selected, and the driving force is reduced, improving the performance and overall efficiency of the shut-off valve.

Description

Technical Field

[0001] This invention relates to the field of fluid control technology and provides a low-flow-resistance, low-leakage shut-off valve. Technical Background

[0002] In the field of aircraft fluid control, the requirements for shut-off valves are low leakage during shut-off and low flow resistance during opening. Currently, for shut-off valves using spring-assisted clamping coaxially with the valve core, the main methods to reduce leakage during shut-off are to improve the machining accuracy of the sealing surface or increase the spring clamping force. The main methods to reduce flow resistance during opening are to increase the opening force or decrease the spring clamping force, so as to increase the valve opening within the allowable stroke. The requirements for the auxiliary role of the spring are opposite in these two aspects, so it is necessary to increase the spring force and set a larger valve opening driving force. For pneumatic valves that are driven by the pressure difference on both sides of the valve core, such as the solution in the existing patent CN201721398660.5, the pressure sensing chamber on the inner side of the valve core has a lower limit requirement for the pressure difference sensing area, which is not conducive to balancing design indicators and has low overall mechanical efficiency, requiring technological innovation. Summary of the Invention

[0003] Purpose of the invention

[0004] A fatigue test load loading device for arresting hook assemblies and components was designed, which effectively solves the problems of poor versatility, unrealistic loading, and long loading cycle of arresting hook fatigue test devices.

[0005] Technical solution

[0006] This invention provides a low-flow-resistance, low-leakage shut-off valve that resolves the contradiction between the desire to increase spring force when the shut-off valve is closed and the desire to reduce spring force when the shut-off valve is open, thereby improving the performance and overall efficiency of the shut-off valve.

[0007] To solve this technical problem, the technical solution of the present invention is as follows:

[0008] A low-flow-resistance, low-leakage shut-off valve is provided, comprising a housing 1, a valve core 7, a variable-elasticity assembly 3, and a sealing ring 6;

[0009] The housing 1 includes an inner housing and an outer housing. The inner housing is a cylindrical body with an opening on one side. The outer housing is a sealed cavity with openings at both ends, which are an inlet and an outlet, respectively. The opening of the inner housing corresponds to the outlet.

[0010] The valve core 7 is located inside the inner shell and is in sliding sealing cooperation with the inner shell;

[0011] The valve core can close the outlet by sliding outward from the cylinder, and can open the outlet by sliding inward from the cylinder;

[0012] An annular cavity is formed between the outer shell and the inner shell, and the inlet communicates with the annular cavity;

[0013] The inner shell is also provided with an air pipe that connects the inner cavity of the cylinder to the outside of the outer shell. The air pipe can control the air pressure in the inner cavity of the cylinder and adjust the pressure difference between the inner cavity of the cylinder and the annular cavity.

[0014] The variable elastic force component 3 is disposed in the inner cavity of the cylinder, and the variable elastic force component 3 is disposed between the inner shell and the valve core. The variable elastic force component 3 applies an elastic pre-tightening force to the valve core so that the valve core normally closes the outlet.

[0015] The elastic preload of the variable elastic force component 3 decreases as the distance the valve core slides into the cylinder increases.

[0016] Furthermore, a servo valve 5 is provided in the trachea to control the pressure inside the trachea.

[0017] Furthermore, the variable elastic force assembly 3 includes a sleeve, a guide rod, a helical spring, a first rotating support 2, and a second rotating support 4; the sleeve and the guide rod are coaxially fitted and axially slidingly engaged, and the helical spring is sleeved outside the sleeve and the guide rod. The sleeve and the guide rod support the helical spring. The sleeve is rotatably disposed in the inner cavity of the cylinder through the first rotating support 2. The guide rod is rotatably connected to the valve core through the second rotating support. The helical spring acts between the cylinder and the valve core. As the valve core slides, the angle between the axis of the sleeve and the guide rod and the sliding direction of the valve core changes.

[0018] Furthermore, the angle between the axes of the sleeve and guide rod and the sliding direction of the valve core satisfies the following equation:

[0019]

[0020] Where α is the included angle value when the valve core is in the closed position, and the value of α is 0°<α<90°;

[0021] β is the angle φ when the valve core slides into the cylinder to its limit position. The value of β is 0°<β<170°.

[0022] R2 is the shortest distance of the second rotating support relative to the sliding direction of the valve core, in mm;

[0023] R1 is the shortest distance of the first rotating support relative to the sliding direction of the valve core, in mm;

[0024] L0 is the free length of the helical spring, in mm;

[0025] k is the equivalent stiffness of the variable elasticity component 3, in N / mm;

[0026] F1 is the preload force of the variable elastic force assembly on the valve core when the valve core is closed, in N;

[0027] F2 is the force exerted by the variable elastic force component on the valve core when the valve core slides into the cylinder to its limit position, in N;

[0028] L represents the stroke of the valve core when it slides into the cylinder to its limit position, expressed in mm.

[0029] Furthermore, the value range can be 90°≤β<170°. At this time, the resultant force of the elastic force on the valve core of the shut-off valve points in the opening direction, and the valve core achieves self-locking. When the shut-off valve needs to be closed, the pressure in the inner cavity 8 of the cylinder can only be controlled by the air pipe 101 and / or the servo valve 5, so that the pressure in the inner cavity of the cylinder increases. Under the action of pressure, the valve core is pushed to slide out of the cylinder and finally closes the outlet.

[0030] Furthermore, the valve core has a weight-reducing groove.

[0031] Furthermore, there are multiple variable elastic force components, which are evenly distributed in a ring shape relative to the sliding direction of the valve core.

[0032] Furthermore, the outer wall surface of the valve core is formed with a stepped surface, which is the surface on which the annular cavity air pressure applies force to the valve core. Even further, the end of the valve core is in line contact with the outlet, and the end of the valve core is a conical surface, which is also the surface on which the annular cavity air pressure applies force to the valve core.

[0033] When the shut-off valve is closed, the angle between the axis of the variable elasticity component and the valve core pressing direction is small, and the component of the elasticity component's rebound force in the valve core pressing direction accounts for a large proportion, resulting in a higher pressing force on the valve core and a higher sealing performance. When the valve is opened, the valve control device connects the outside atmosphere to the inner cavity of the valve core through the air passage inside the housing, reducing the pressure inside the valve core. The resultant force of the air pressure difference received by the valve core points in the valve core opening direction, overcoming the force of the variable elasticity component and causing the valve core to slide into the cylinder. At this time, the variable elasticity component begins to swing with the valve core while compressing, and the angle between the axis of the variable elasticity component and the valve core pressing direction begins to increase. The proportion of its force component acting in the valve core pressing direction begins to decrease. Under the same pressure difference driving force, the valve core can achieve a larger opening degree, increasing the valve flow area and reducing the valve flow resistance.

[0034] Beneficial effects

[0035] The shut-off valve of the present invention has a higher clamping force on the valve core when the valve is closed, which can improve the sealing performance. When the valve is open, the valve opening degree can be increased under the same valve core opening force, reducing the flow resistance of the shut-off valve and allowing for a reduction in the design driving force, reducing the weight of the electromagnet used for driving or reducing the force required for manual opening, thereby improving the overall efficiency of the mechanical structure. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the shut-off valve structure of the present invention;

[0037] Figure 2 This is a three-dimensional sectional view (closed position) of the shut-off valve of the present invention;

[0038] Figure 3 This is a three-dimensional sectional view (open position) of the shut-off valve of the present invention;

[0039] Figure 4 This is a three-dimensional cross-sectional view of the variable elastic force component of the present invention;

[0040] Figure 5 This is a three-dimensional schematic diagram showing the connection relationship between the variable elastic force component and the two rotating supports of the present invention;

[0041] Figure 6 This is a three-dimensional sectional view of the shut-off valve of the present invention;

[0042] Figure 7 This is a schematic diagram of the variable elastic force component and elastic force decomposition in an embodiment of the present invention;

[0043] Figure 8 A schematic diagram of the spring configuration for an existing shut-off valve;

[0044] Wherein: 1 is the shell, 2 is the first rotating support, 3 is the variable elastic force component, 4 is the second rotating support, 5 is the servo valve, 6 is the sealing ring, 7 is the valve core, 8 is the inner cavity of the cylinder; 101 is the air pipe, 102 is the outer shell, 103 is the inner shell; 301 is the sleeve, 302 is the helical spring, and 303 is the guide rod. Detailed Implementation

[0045] The disclosed examples will be described more fully with reference to the accompanying drawings, in which some (but not all) of the disclosed examples are shown. In fact, many different examples may be described, and these examples should not be construed as limited to those set forth herein. Rather, these examples are described so that this disclosure will be thorough and complete, and will fully convey the scope of this disclosure to those skilled in the art.

[0046] A low-flow-resistance, low-leakage shut-off valve is provided, comprising a housing 1, a valve core 7, a variable-elasticity assembly 3, and a sealing ring 6;

[0047] The housing 1 includes an inner housing and an outer housing. The inner housing is a cylindrical body with an opening on one side. The outer housing is a sealed cavity with openings at both ends, which are an inlet and an outlet, respectively. The opening of the inner housing corresponds to the outlet.

[0048] The valve core 7 is located inside the inner shell and is in sliding sealing cooperation with the inner shell;

[0049] The valve core can close the outlet by sliding outward from the cylinder, and can open the outlet by sliding inward from the cylinder;

[0050] An annular cavity is formed between the outer shell and the inner shell, and the inlet communicates with the annular cavity;

[0051] The inner shell is also provided with an air pipe that connects the inner cavity of the cylinder to the outside of the outer shell. The air pipe can control the air pressure in the inner cavity of the cylinder and adjust the pressure difference between the inner cavity of the cylinder and the annular cavity.

[0052] The variable elastic force component 3 is disposed in the inner cavity of the cylinder, and the variable elastic force component 3 is disposed between the inner shell and the valve core. The variable elastic force component 3 applies an elastic pre-tightening force to the valve core so that the valve core normally closes the outlet.

[0053] The elastic preload of the variable elastic force component 3 decreases as the distance the valve core slides into the cylinder increases.

[0054] A servo valve 5 is installed in the air pipe to control the pressure inside the air pipe.

[0055] The variable elastic force assembly 3 includes a sleeve, a guide rod, a helical spring, a first rotating support 2, and a second rotating support 4. The sleeve and the guide rod are coaxially fitted and axially slidingly engaged. The helical spring is sleeved outside the sleeve and the guide rod, and the sleeve and the guide rod support the helical spring. The sleeve is rotatably mounted in the inner cavity of the cylinder via the first rotating support 2. The guide rod is rotatably connected to the valve core via the second rotating support. The helical spring acts between the cylinder and the valve core. As the valve core slides, the angle between the axis of the sleeve and the guide rod and the sliding direction of the valve core changes.

[0056] Furthermore, the angle between the axes of the sleeve and guide rod and the sliding direction of the valve core satisfies the following equation:

[0057]

[0058] Where α is the included angle value when the valve core is in the closed position, and the value of α is 0°<α<90°;

[0059] β is the angle φ when the valve core slides into the cylinder to its limit position. The value of β is 0°<β<170°.

[0060] R2 is the shortest distance of the second rotating support relative to the sliding direction of the valve core, in mm;

[0061] R1 is the shortest distance of the first rotating support relative to the sliding direction of the valve core, in mm;

[0062] L0 is the free length of the helical spring, in mm;

[0063] k is the equivalent stiffness of the variable elasticity component 3, in N / mm;

[0064] F1 is the preload force of the variable elastic force assembly on the valve core when the valve core is closed, in N;

[0065] F2 is the force exerted by the variable elastic force component on the valve core when the valve core slides into the cylinder to its limit position, in N;

[0066] L represents the stroke of the valve core when it slides into the cylinder to its limit position, expressed in mm.

[0067] The valve core has a weight-reducing groove.

[0068] There are three variable elastic force components, which are evenly distributed in a ring shape relative to the sliding direction of the valve core.

[0069] The outer wall of the valve core has a stepped surface, which is the surface on which the annular air pressure applies force to the valve core. The end of the valve core is in line contact with the outlet. The end of the valve core is a conical surface, which is also the surface on which the annular air pressure applies force to the valve core.

[0070] Under a specific working pressure, the valve control device can provide a differential pressure of 29.4N in the valve core opening direction. The first rotating support is a hinge with R1 of 18.85mm, the second rotating support is a hinge with R2 of 8.85mm, the free length of the helical spring is 30mm, and the overall equivalent stiffness k of the helical springs of the three variable elastic force components is 2.63N / mm.

[0071] When the valve core is in the closed position, the angle α between the axis of the variable spring force component and the valve core pressing direction is 26.56°. At this time, the spring length is 22.36 mm, the compression is 7.64 mm, and the algebraic sum of the forces of the three variable spring force components is 20.09 N. The resultant force components along the normal plane of the valve core axis cancel each other out, and the pressing force F1 on the valve core is 17.97 N.

[0072] When the valve core is opened, the clamping force of the elastic module on the valve core shows a trend of increasing and then decreasing, reaching a maximum value of 29.15N when the included angle is 45°. The valve core will move to the stroke limit point. At this time, the angle β between the axis of the variable elastic force component and the clamping direction of the valve core is 51.34°, and the opening L reaches the upper limit of 12mm.

[0073] In contrast, a traditional approach using elastic elements arranged coaxially with the valve core is employed, such as... Figure 8 As shown, its parameters are: spring free length 50mm, spring stiffness 2.1N / mm; when the valve core is in the closed position, the spring length is 45mm, the compression is 5mm, and the rebound force is equal to the valve core clamping force of 10.5N; when the valve core is open, the spring clamping force received by the valve core increases linearly, and reaches the maximum opening of 9mm when it is balanced with the 29.4N pressure difference force guaranteed by the control device.

[0074] The comparison shows that the valve core clamping force of the shut-off valve structure of the present invention is 19.97N when the shut-off valve is closed, which is higher than the 10.5N clamping force of the shut-off valve structure of the existing structure. The valve core opening is 12mm when the shut-off valve is open, which is greater than the opening of the existing structure by 9mm. Both indicators are better than the existing structure. Moreover, the adjustment spring stiffness of the shut-off valve of the existing structure cannot take both indicators into account at the same time, and one of them will always deteriorate. This shows that under the condition that the driving force guaranteed by the valve control device is certain, the low flow resistance and low leakage shut-off valve of the present invention has performance advantages.

[0075] The shut-off valve in this embodiment has a higher clamping force on the valve core when the valve is closed, which can improve the sealing performance. When the valve is open, the valve opening degree can be increased under the same valve core opening force, reducing the flow resistance of the shut-off valve and allowing for a reduction in the design driving force. This reduces the weight of the electromagnet used for driving or the force required for manual opening, thereby improving the overall efficiency of the mechanical structure.

[0076] Descriptions of various advantageous arrangements have been shown for illustrative and descriptive purposes, but such descriptions are not intended to be exclusive or limited to the disclosed forms. Many modifications and variations will be apparent to those skilled in the art. Furthermore, different advantageous examples may describe different advantages compared to other advantageous examples. One or more examples have been selected and described in order to best illustrate the principles and practical application of the examples, and to enable those skilled in the art to understand that this disclosure contains various examples with various modifications suitable for the particular intended use.

Claims

1. A low-flow-resistance, low-leakage shut-off valve, characterized in that: Includes housing, valve core, variable spring force assembly, and sealing ring; The housing includes an inner housing and an outer housing. The inner housing is a cylindrical body with an opening on one side. The outer housing is a sealed cavity with openings at both ends, which are an inlet and an outlet, respectively. The opening of the inner housing corresponds to the outlet. The valve core is located inside the inner shell and is in sliding sealing cooperation with the inner shell; The valve core can close the outlet by sliding outward from the cylinder, and can open the outlet by sliding inward from the cylinder; An annular cavity is formed between the outer shell and the inner shell, and the inlet communicates with the annular cavity; The inner shell is also provided with an air pipe that connects the inner cavity of the cylinder to the outside of the outer shell. The air pipe can control the air pressure in the inner cavity of the cylinder and adjust the pressure difference between the inner cavity of the cylinder and the annular cavity. The variable elastic force component is disposed in the inner cavity of the cylinder, and is disposed between the inner shell and the valve core. The variable elastic force component applies an elastic preload to the valve core so that the valve core normally closes the outlet. The elastic preload of the variable elastic force component decreases as the distance the valve core slides into the cylinder increases; A servo valve is installed in the trachea to control the pressure inside the trachea; The variable elastic force assembly includes a sleeve, a guide rod, a helical spring, a first rotating support, and a second rotating support. The sleeve and the guide rod are coaxially fitted and axially slidingly engaged. The helical spring is sleeved outside the sleeve and the guide rod, and the sleeve and the guide rod support the helical spring. The sleeve is rotatably mounted in the inner cavity of the cylinder via the first rotating support. The guide rod is rotatably connected to the valve core via the second rotating support. The helical spring acts between the cylinder and the valve core. As the valve core slides, the angle between the axes of the sleeve and the guide rod and the sliding direction of the valve core changes.

2. The low flow resistance, low leakage shut-off valve according to claim 1, characterized in that: The angle between the axes of the sleeve and guide rod and the sliding direction of the valve core satisfies the following equation: Where α is the included angle value when the valve core is in the closed position, and the value of α is 0°<α<90°; β is the angle value when the valve core slides into the cylinder to the limit position, and the value of β is 0°<β<170°; R2 is the shortest distance of the second rotating support relative to the sliding direction of the valve core, in mm; R1 is the shortest distance of the first rotating support relative to the sliding direction of the valve core, in mm; L0 is the free length of the helical spring, in mm; k is the equivalent stiffness of the variable elasticity component, in N / mm; F1 is the preload force of the variable elastic force assembly on the valve core when the valve core is closed, in N; F2 is the force exerted by the variable elastic force component on the valve core when the valve core slides into the cylinder to its limit position, in N; L represents the stroke of the valve core when it slides into the cylinder to its limit position, expressed in mm.

3. The low flow resistance and low leakage shut-off valve according to claim 2, characterized in that: The value range is 90°≤β<170°; when β=90°, the resultant elastic force on the valve core of the shut-off valve is perpendicular to the opening direction, and the valve core achieves self-locking. When the shut-off valve needs to be closed, the pressure in the inner cavity of the cylinder can only be controlled by the air pipe and / or servo valve, so that the pressure in the inner cavity of the cylinder increases, and under the action of pressure, the valve core is pushed to slide out of the cylinder and finally closes the outlet.

4. A low-flow-resistance, low-leakage shut-off valve according to any one of claims 1-3, characterized in that: The valve core has a weight-reducing groove.

5. A low-flow-resistance, low-leakage shut-off valve according to any one of claims 1-3, characterized in that: The variable elastic force components are multiple and are evenly distributed in a ring shape relative to the sliding direction of the valve core.

6. A low-flow-resistance, low-leakage shut-off valve according to any one of claims 1-3, characterized in that: The outer wall of the valve core has a stepped surface, which is the surface on which the annular air pressure exerts force on the valve core.

7. A low-flow-resistance, low-leakage shut-off valve according to any one of claims 1-3, characterized in that: The end of the valve core is in line contact with the outlet, and the end of the valve core is a conical surface, which is also the surface on which the annular air pressure applies force to the valve core.

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