Air tightness detection valve group

Abstract

The air tightness detection valve group comprises a pilot air source, a working air source, a first pneumatic control valve group and a first pilot valve. The first pneumatic control valve set comprises a valve body, a piston arranged in the pilot cavity and a sliding block connected with the piston and arranged in the working cavity, the valve body is provided with the pilot cavity, the working cavity, a testing cavity and a reference cavity, and the valve body is provided with a first air inlet channel communicating with the working cavity and a working air source and further provided with a second air inlet channel communicating with the first pilot valve and the pilot cavity. The test cavity is provided with a third air inlet channel communicated with the working cavity, and the reference cavity is provided with a fourth air inlet channel communicated with the working cavity. The sliding block is arranged on the same side of the third air inlet channel and the fourth air inlet channel. The first pilot valve introduces or discharges pilot gas into or out of the pilot cavity through the second gas inlet channel to push the piston to drive the sliding block to move in the working cavity in the first direction so as to synchronously control connection or disconnection between the test cavity and the working cavity and between the reference cavity and the working cavity and between the test cavity and the working cavity and between the reference cavity and the working cavity. The air tightness detection valve provided by the utility model has better detection precision.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of air tightness detection, in particular to an air tightness detection valve group. BACKGROUND

[0002] The principle of differential pressure type air tightness detection is to use compressed gas as a medium for detection, wherein a differential pressure sensor is connected to a completely leak-free standard cavity (reference end) and a measured workpiece (test end), at this time the first valve is opened for inflation, after inflation the second valve and the third valve are opened for sealing, if the measured workpiece has a leak, the differential pressure sensor will detect the pressure difference in time and determine whether the part is qualified.

[0003] However, the related art usually controls the detection process through a valve body, and opens the second valve and the third valve manually or electrically, which is difficult to keep the second valve and the third valve open at the same time, resulting in low measurement accuracy of the detection valve in the related art. CONTENT OF THE UTILITY MODEL

[0004] Therefore, it is necessary to provide an air tightness detection valve group to solve the problem of low detection accuracy of the detection valve in the related art.

[0005] According to one aspect of the present application, an air tightness detection valve group is provided, which comprises a pilot gas source, a working gas source, a first gas control valve group and a first pilot valve, the pilot gas source is used to supply gas to the gas inlet end of the first pilot valve, and the working gas source is used to supply gas to the gas inlet end of the first gas control valve group.

[0006] The first gas control valve group comprises a valve body, a piston and a slider, the valve body has a pilot cavity, a working cavity, a test cavity and a reference cavity, the valve body is provided with a first gas inlet channel communicating the working cavity and the working gas source, and the valve body is provided with a second gas inlet channel communicating the first pilot valve and the pilot cavity; the test cavity has a third gas inlet channel communicating the working cavity, and the reference cavity has a fourth gas inlet channel communicating the working cavity;

[0007] The slider is connected to the piston, the piston is arranged in the pilot cavity, the slider is arranged in the working cavity, the piston is fixedly connected to the slider, and the slider is arranged on the same side of the third gas inlet channel and the fourth gas inlet channel; the first pilot valve is used to introduce or discharge pilot gas into the pilot cavity through the second gas inlet channel to push the piston and drive the slider to move in the working cavity in a first direction, so as to synchronously move away from or abut against the third gas inlet channel and the fourth gas inlet channel, and control the test cavity and the reference cavity to be communicated or blocked with the working cavity.

[0008] In one of the embodiments, the first pilot valve is a balanced pilot valve.

[0009] In one of the embodiments, the test chamber and the reference chamber are symmetrically arranged, and the slider is symmetrically arranged.

[0010] In one of the embodiments, the valve body comprises a main body, a cover plate and a first isolation part, the cover plate is arranged on one side of the main body and cooperates with the main body to define a receiving chamber, the first isolation part is arranged in the receiving chamber and separates the working chamber, the test chamber and the reference chamber, and the third air inlet channel and the fourth air inlet channel are both arranged in the first isolation part.

[0011] The first air control valve group further comprises a first elastic member, the first isolation part has a guide groove arranged between the test chamber and the reference chamber and extending along the first direction, the slider has a first limiting protrusion extending along the first direction, the first limiting protrusion at least partially extends into the guide groove, and the first elastic member is arranged between the bottom wall of the guide groove and the slider.

[0012] In one of the embodiments, the side of the first isolation part facing the working chamber has an abutting bottom wall, the abutting bottom wall is a plane, and the third air inlet channel and the fourth air inlet channel are both arranged in the abutting bottom wall; when the slider abuts against the abutting bottom wall, the slider is in the blocking state, and the third air inlet channel and the fourth air inlet channel are both blocked with the working chamber; when the slider is away from the abutting bottom wall, the slider is in the conducting state, and the third air inlet channel and the fourth air inlet channel are both conducted with the working chamber.

[0013] In one of the embodiments, the first air control valve group further comprises a first sealing structure, and the first sealing structure is arranged between the slider and the inner wall of the guide groove.

[0014] In one of the embodiments, the valve body further comprises a second isolation part, the second isolation part is arranged in the receiving chamber and separates the working chamber and the pilot chamber, the second isolation part has a guide channel penetrating along the first direction, the slider has a second limiting protrusion extending along the first direction, the piston is connected with the second limiting protrusion, and the second limiting protrusion at least partially extends into the guide channel.

[0015] The cover plate is provided with a first channel communicated with the air outlet end of the first pilot valve, the second isolation part is provided with a second channel communicated with the pilot chamber, and the first channel and the second channel are communicated to form the second air inlet channel.

[0016] The second limiting protrusion and the inner wall of the guide channel are provided with a second sealing structure.

[0017] In one of the embodiments, the first pneumatic valve group further comprises a second elastic member, which is arranged between the side of the piston facing away from the slider and the cover plate;

[0018] The second elastic member is in a compressed state in the first direction, and the elastic force of the second elastic member is greater than the elastic force of the first elastic member.

[0019] In one of the embodiments, the air tightness detection valve group further comprises a second pneumatic valve group and a second pilot valve, the second pneumatic valve group is arranged on the gas passage between the working gas source and the first pneumatic valve group;

[0020] The pilot gas source is connected to the second pneumatic valve group for introducing pilot gas into the second pneumatic valve group to drive the second pneumatic valve group to work;

[0021] The second pilot valve is arranged on the gas passage between the pilot gas source and the second pneumatic valve group.

[0022] In one of the embodiments, the air tightness detection valve group further comprises an exhaust pilot valve, which is arranged on the gas passage between the pilot gas source and the second pneumatic valve group, and is used for introducing pilot gas into the second pneumatic valve group to drive the second pneumatic valve group to exhaust working gas to the outside.

[0023] In one of the embodiments, the air tightness detection valve group further comprises a differential pressure sensor and a pressure sensor, the differential pressure sensor comprises a first detection end and a second detection end, the first detection end is arranged on the gas passage between the test chamber and the chamber to be detected, and the second detection end is arranged on the gas passage between the reference chamber and the standard chamber; the pressure sensor is arranged on the gas passage between the first pneumatic valve group and the second pneumatic valve group.

[0024] In one of the embodiments, the air tightness detection valve group further comprises an exhaust passage, which is connected to the pilot chamber and the outside, and the first pilot valve is arranged on the exhaust passage.

[0025] The airtightness detection valve, the test cavity is communicated with the cavity to be detected, the reference cavity is communicated with the standard cavity, before detection, the working cavity, the test cavity and the reference cavity are in the open state, the air pressure between the test cavity and the reference cavity is balanced, or the air pressure between the cavity to be detected and the standard cavity is balanced. When the detection starts, the working cavity, the test cavity and the reference cavity are in the isolation state, whether the standard cavity has the pressure difference with the cavity to be detected can be determined by corresponding detection of whether the test cavity and the reference cavity have the pressure difference. It can be understood that if there is no pressure difference between the standard cavity and the cavity to be detected, it indicates that the cavity to be detected does not leak and the sealing is good, if there is a pressure difference, it indicates that the cavity to be detected leaks and the sealing is damaged. The airtightness detection valve uses the way of stop type sealing to make the sealing more reliable and improve the precision. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 A simplified diagram showing the basic principle of differential pressure type airtightness detection.

[0027] Figure 2 A structure schematic diagram of the airtightness detection valve group of an embodiment of the application is shown.

[0028] Figure 3 A sectional view of the airtightness detection valve group of an embodiment of the application is shown.

[0029] Figure 4 A gas circuit diagram of the airtightness detection valve group of an embodiment of the application is shown.

[0030] Figure 5 An enlarged view of the slider in an embodiment of the application.

[0031] BRIEF DESCRIPTION OF DRAWINGS

[0032] 10, airtightness detection valve group;

[0033] 100, first pneumatic valve group; 110, valve body; 1101, main body; 1102, cover plate; 111, working cavity; 112, test cavity; 113, reference cavity; 114, pilot cavity; 115, second air inlet channel; 120, slider; 121, first limiting protrusion; 122, second limiting protrusion; 130, first elastic member; 141, second elastic member; 142, piston; 150, second isolation part; 151, second sealing structure; 152, guide channel; 160, first isolation part; 161, third air inlet channel; 162, fourth air inlet channel; 163, guide groove; 164, first sealing structure; 170, exhaust channel:

[0034] 200, differential pressure sensor; 300, second pneumatic valve group; 400, working gas source; 500, second pilot valve; 600, pilot gas source; 700, first pilot valve; 800, exhaust pilot valve; 900, pressure sensor;

[0035] A. First valve; B. Second valve; C. Third valve; D. Sensor; M. Standard chamber; N. Chamber to be tested;

[0036] F1, first direction; F2, second direction. Detailed Implementation

[0037] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0038] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0039] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0040] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0041] In this application, unless otherwise clearly specified and limited, if there is a description of a first feature "on" or "under" a second feature, etc., it can mean that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature "on", "above" and "over" the second feature can be that the first feature is directly above or obliquely above the second feature, or only means that the first feature is horizontally higher than the second feature. The first feature "under", "below" and "under" the second feature can be that the first feature is directly below or obliquely below the second feature, or only means that the first feature is horizontally lower than the second feature.

[0042] It should be noted that if an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there can be an intermediate element. If an element is considered to be "connected" to another element, it can be directly connected to the other element or there can be an intermediate element. If present, the terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used in this application are only for illustrative purposes and do not represent the only implementation.

[0043] The principle of differential pressure type air tightness detection is to use compressed gas as a medium for detection, as shown in Figure 1 Figure 1 is a simplified diagram of the basic principle of differential pressure type air tightness detection. A sensor D is used to connect a completely leak-free standard cavity (standard cavity M) and a workpiece to be measured (cavity N) respectively, at this time the first valve A is opened for charging, after charging is completed, the second valve B and the third valve C are opened simultaneously for sealing, if the measured workpiece has a leak, the differential pressure sensor will detect the pressure difference in time and judge whether the part is qualified. The whole test process usually consists of four steps: charging, pressure maintaining, testing and exhausting, which has the advantages of low cost, high precision and fast speed compared with pressure drop method, helium detection method and immersion method.

[0044] There are many methods to realize differential pressure type air tightness detection in related technologies. For example, the first method uses Figure 1 ​The shown scheme is directly controlled by three electromagnetic valves. As the second kind, a plurality of air control valves are used to control the working gas path. As the third kind, a valve group assembly is formed, and a sliding column seal is used to realize the differential pressure detection function. However, generally, the detection accuracy of the first kind is poor, and the temperature rise of the electromagnetic valve itself during use will also seriously affect the test results, and high-precision detection cannot be realized. The second kind isolates the influence of the temperature rise of the electromagnetic valve, and the temperature rise of the electromagnetic valve will not affect the detection accuracy, but the overall volume is increased, the leakage points are increased, and the consistency and sealing performance of the air control valve are required to be high. From this aspect, it is also difficult to realize high-precision detection. The third kind reduces the impact of the sliding column seal, but the sealing performance of the sealing element is required to be high, the overall sealing is difficult to guarantee, and the yield is low, and it is also difficult to realize high-precision detection.

[0045] And the related art generally controls the detection process through the valve body, and opens the second valve B and the third valve C manually or electrically, and it is difficult to keep the second valve B and the third valve C open at the same time, which leads to low measurement accuracy of the detection valve in the related art.

[0046] Therefore, a gas tightness detection valve group is provided to improve the detection accuracy of the workpiece to be detected, and to facilitate miniaturization design, reduce leakage points, and facilitate maintenance.

[0047] Referring to Figure 2 , Figure 3 and Figure 4 , Figure 2 a structure diagram of a gas tightness detection valve group 10 of an embodiment of the application is shown. Figure 3 a sectional view of the gas tightness detection valve of an embodiment of the application is shown. Figure 4 a gas path diagram of the gas tightness detection valve group 10 of an embodiment of the application is shown.

[0048] The application provides a gas tightness detection valve group 10 for supplying air to the workpiece to be detected and the standard piece, and can equalize the air pressure between the detection cavity N of the workpiece to be detected and the standard cavity M of the standard piece before detection. During detection, whether there is a pressure difference between the detection cavity N and the standard cavity M is detected, so as to judge whether the detection cavity N is sealed perfectly.

[0049] The air tightness detection valve group 10 provided by the application can include a pilot gas source 600, a working gas source 400, a first gas control valve group 100, and a first pilot valve 700. The pilot gas source 600 is used to ventilate the gas inlet end of the first pilot valve 700, and the working gas source 400 is used to ventilate the gas inlet end of the first gas control valve group 100. The first gas control valve group 100 includes a valve body 110, a piston 142, and a slider 120. The valve body 110 has a pilot cavity 114, a working cavity 111, a test cavity 112, and a reference cavity 113. The valve body 110 is provided with a first gas inlet channel that communicates the working cavity 111 with the working gas source 400, and a second gas inlet channel 115 that communicates the first pilot valve 700 with the pilot cavity 114. The test cavity 112 has a third gas inlet channel 161 that communicates the working cavity 111, and the reference cavity 113 has a fourth gas inlet channel 162 that communicates the working cavity 111.

[0050] The slider 120 is connected with the piston 142. The piston 142 is arranged in the pilot cavity 114, and the slider 120 is arranged in the working cavity 111. The piston 142 is fixedly connected with the slider 120, and the slider 120 is arranged on the same side of the third gas inlet channel 161 and the fourth gas inlet channel 162. The first pilot valve 700 is used to introduce or discharge the pilot gas into the pilot cavity 114 through the second gas inlet channel 115 to push the piston 142 and drive the slider 120 to move in the working cavity 111 along a first direction F1, so as to synchronously move away from or abut against the third gas inlet channel 161 and the fourth gas inlet channel 162, and control the test cavity 112 and the reference cavity 113 to be communicated or blocked with the working cavity 111, respectively.

[0051] In the ideal state, the slider 120 can abut against the third gas inlet channel 161 and the fourth gas inlet channel 162 at the same time, so as to simultaneously block the test cavity 112 and the reference cavity 113 with the working cavity 111, which means that the time for ventilating the test cavity 112 and the reference cavity 113 through the working cavity 111 is the same, thereby facilitating the equalization and stability of the gas pressure in the test cavity 112 and the reference cavity 113, and further facilitating the improvement of the detection precision. In addition, the slider 120 can move away from the third gas inlet channel 161 and the fourth gas inlet channel 162 at the same time, so as to simultaneously communicate the test cavity 112 and the reference cavity 113 with the working cavity 111, thereby facilitating the working state of the test cavity 112 and the reference cavity 113 to be the same, and being in the same working condition, and further facilitating the reduction of the wear or precision difference caused by the influence of the environment, and the working conditions of the test cavity 112 and the reference cavity 113 are still the same after long-term use, thereby facilitating the improvement of the detection precision of the air tightness detection valve group 10 after long-term use.

[0052] In the embodiment, the slider 120 is arranged on the same side of the third air inlet channel 161 and the fourth air inlet channel 162, and the same slider 120 is used to control the communication or block of the test cavity 112 and the reference cavity 113 with the working cavity 111. Therefore, when the slider 120 moves in one direction, the slider 120 is away from or abuts against the third air inlet channel 161 and the fourth air inlet channel 162 at the same time. It can be understood that due to the machining precision of the device, the installation precision of the equipment, and the like, there may be errors, and the third air inlet channel 161 and the fourth air inlet channel 162 are not absolutely away from or abut against at the same time. The specific determination can be made according to the actual situation, and the embodiment of the specification is not limited in this regard.

[0053] In the embodiment, the first direction F1 can be the extension direction of the piston 142 in the direction of the slider 120, or it can be understood that the first direction F1 is the longitudinal extension direction of the valve body 110 of the first air control valve group 100. Figure 3

[0054] In the embodiment, the pilot gas source 600 can be a gas source for discharging gas into the first pilot valve 700 to control the movement of the piston 142, and the working gas source 400 can be a gas source for discharging gas into the test cavity 112 and the reference cavity 113 for gas tightness test. The gas types of the pilot gas source 600 and the working gas source 400 can be the same or different, and the specific determination can be made according to the actual situation, and the embodiment of the specification is not limited in this regard.

[0055] In the embodiment, the pilot valve is an auxiliary valve that controls and regulates the hydraulic system. It controls the opening and closing of the main valve by controlling the hydraulic signal, so as to realize the normal operation of the hydraulic system. The first pilot valve can be a pilot electromagnetic valve, a pilot safety valve (used for protecting the safety of equipment and pipelines), a pilot balance valve (used for regulating the flow and pressure of fluid medium), a pilot large flow valve, and the like. The specific determination can be made according to the actual situation, and the embodiment of the specification is not limited in this regard.

[0056] In the embodiment, the pilot cavity 114, the working cavity 111, the test cavity 112, and the reference cavity 113 can have a communication channel therebetween, or the pilot cavity 114, the working cavity 111, the test cavity 112, and the reference cavity 113 can be isolated from each other by a sealing member.

[0057] ​In the embodiment, the piston 142 can be arranged in the pilot chamber 114, and when the first pilot valve introduces pilot gas into the pilot chamber 114 through the second gas inlet channel 115, the introduced pilot gas can push the piston 142 to move away from the working chamber 111. The piston 142 can be generally arranged as a cylinder, and the diameter of the piston 142 can be matched with or slightly smaller than the size of the pilot chamber 114. It can be understood that the piston 142 can also be arranged in other possible shapes, for example, square, polygon, etc., which can be determined according to actual conditions, and the embodiment of the present application does not limit this.

[0058] In the embodiment, the slider 120 can be a smooth block structure, and the block structure can have upper and lower protrusions, or can have none of the upper and lower protrusions or both of the upper and lower protrusions, or can be symmetrical relative to a plane parallel to the first direction F1, or can be arranged as an asymmetric block structure, which is not limited herein. It can be understood that if the slider 120 is asymmetric, in order to enable the slider 120 to be synchronized with the test chamber 112 and the reference chamber 113, the corresponding test chamber 112 and reference chamber 113 also need to have corresponding asymmetric structures. According to actual conditions, the slider 120 can be asymmetric, and the corresponding test chamber 112 and reference chamber 113 can also be symmetrical.

[0059] In the embodiment, correspondingly, the third gas inlet channel 161 can be located between the working chamber 111 and the test chamber 112, and the fourth gas inlet channel 162 can be located between the working chamber 111 and the reference chamber 113. The third gas inlet channel 161 and the fourth gas inlet channel 162 can be located on the same side of the slider 120 along the first direction F1, and the test chamber 112 and the reference chamber 113 can also be located on the same side of the slider 120 along the first direction F1. The test chamber 112 is located on the side of the third gas inlet channel 161 away from the working chamber 111 along the first direction F1, and the reference chamber 113 is located on the side of the fourth gas inlet channel 162 away from the working chamber 111 along the first direction F1. The test chamber 112 and the reference chamber 113 can be arranged symmetrically relative to a plane parallel to the first direction F1. The longitudinal dimension of the third gas inlet channel 161 can be much smaller than the longitudinal dimension of the test chamber 112, and the longitudinal dimension of the fourth gas inlet channel 162 can be much smaller than the longitudinal dimension of the reference chamber 113. The size of the third gas inlet channel 161 and the fourth gas inlet channel 162 can be used to limit the slow introduction of working gas into the test chamber 112 and the reference chamber 113, thereby improving the stability of gas supply and improving the detection accuracy. The positions and layouts of the third gas inlet channel 161, the fourth gas inlet channel 162, the test chamber 112 and the reference chamber 113, and the shapes and sizes thereof can be selected and designed according to actual conditions, which are not limited herein.

[0060] In the embodiment, the piston 142 and the slider 120 can be integrated, and in some embodiments, the piston 142 and the slider 120 can also be two separate structures for convenient installation. The piston 142 and the slider 120 can be fixed by screws or other locking members or can be clamped, which is not limited herein.

[0061] In the embodiment, either one or both of the guide channel 152 and the guide groove 163 can be arranged on the valve body 110, and the guide channel 152 and the guide groove 163 can both extend along the first direction F1. When both the guide channel 152 and the guide groove 163 are arranged, the guide channel 152 and the guide groove 163 can be arranged at intervals along the first direction F1, and a part of the slider 120 can be extended into the guide channel 152, and another part of the slider 120 can be extended into the guide groove 163, so that the guide channel 152 and the guide groove 163 can guide the slider 120, the stability of the movement of the slider 120 in the first direction F1 is increased, the smoothness of the plugging of the slider 120 in the third intake channel 161 and the fourth intake channel 162 is increased, and the stability of the gas supply in the test cavity 112 and the reference cavity 113 is improved, and the detection stability is improved.

[0062] The air tightness detection valve of the present application, the test cavity 112 is communicated with the to-be-tested cavity N, and the reference cavity 113 is communicated with the standard cavity M. Before detection, the working cavity 111, the test cavity 112 and the reference cavity 113 are in a conductive state, the gas pressure between the test cavity 112 and the reference cavity 113 is balanced, or the gas pressure between the to-be-tested cavity N and the standard cavity M is balanced. At the beginning of detection, the first pilot valve 700 needs to be powered and reversed, the working cavity 111, the test cavity 112 and the reference cavity 113 are in an isolated state, and after setting the time pressure maintaining, the pressure difference is read to judge. Whether the standard cavity M and the to-be-tested cavity N have a pressure difference can be determined by detecting whether the test cavity 112 and the reference cavity 113 have a pressure difference. The first pilot valve 700 needs to be powered and reversed, and after setting the time pressure maintaining, the pressure difference is read to judge. It can be understood that if there is no pressure difference between the standard cavity M and the to-be-tested cavity N, it means that the to-be-tested member connected to the test cavity 112 does not leak and has good sealing. If there is a pressure difference, it means that the to-be-tested member connected to the test cavity 112 leaks and the sealing is damaged.

[0063] From the above description, it can be seen that the embodiments of the present application achieve the following technical effects:

[0064] The slider 120 is synchronously away from or abuts against the third air inlet channel 161 and the fourth air inlet channel 162, which is beneficial for equalizing and stabilizing the gas pressure in the test cavity 112 and the reference cavity 113, and further beneficial for improving the detection accuracy. The guide channel 152 and the guide groove 163 guide the slider 120, which is beneficial for increasing the stability of the slider 120 blocking the third air inlet channel 161 and the fourth air inlet channel 162, and further beneficial for improving the gas supply stability in the test cavity 112 and the reference cavity 113, improving the consistency of the gas pressure in the test cavity 112 and the reference cavity 113, and further improving the detection stability. The test cavity 112 and the reference cavity 113 can be symmetrically arranged, and the slider 120 can be symmetrically arranged, which is beneficial for simplifying the preparation process of the valve body 110 and the slider 120, easy to manufacture, and beneficial for making the valve body 110 and the slider 120 simple in structure, and beneficial for realizing miniaturization design. The first sealing structure 164 is arranged between the slider 120 and the guide groove 163, which is beneficial for isolating the working cavity 111 from the guide groove 163 or the outside world, and further beneficial for improving the air tightness in the working cavity 111 and improving the accuracy of the air tightness detection. The second sealing structure 151 is arranged between the second limiting protrusion 122 and the inner wall of the guide channel 152, which is further beneficial for improving the air tightness in the working cavity 111 and improving the accuracy of the air tightness detection. The first elastic member 130 and the second elastic member 141 provide buffering for the movement of the slider 120 and the piston 142, and cooperate with the small-flow first pilot valve 700 to have the effect of exhaust buffering, so that the slider 120 can be buffered during movement, reducing the risk of collision and damage of the slider 120, reducing the impact force of the slider 120 and the part in contact with the slider 120, which is beneficial for improving the service life of the air tightness detection valve group 10, and the buffering effect of the first elastic member 130, the second elastic member 141 and the first pilot valve 700 greatly weakens the pressure difference caused by the impact influence of the movement of the slider 120, improving the detection accuracy.

[0065] In some embodiments, the first pilot valve 700 can be a balanced pilot valve. The exhaust flow passage of the balanced pilot valve 6 is small, and the small-flow first pilot valve 700 has the effect of exhaust buffering, which can greatly weaken the temperature rise caused by the sealing of the slider 120 during exhaust and the impact influence of the slider 120, and further improve the accuracy of the air tightness detection.

[0066] In some embodiments, as Figure 3, the test cavity 112 and the reference cavity 113 can be symmetrically arranged, and the slider 120 can be symmetrically arranged. By the design that the test cavity 112 and the reference cavity 113 are symmetrically arranged and the slider 120 is symmetrically arranged, firstly, the preparation process of the valve body 110 and the slider 120 is simplified, and the valve body 110 and the slider 120 are easy to manufacture and install after manufacturing; secondly, the valve body 110 and the slider 120 are simple in structure, and miniaturization design is facilitated. The symmetrically arranged slider 120 and the symmetrically arranged test cavity 112 and reference cavity 113 can simultaneously inflate and cut off the inflation of the test cavity 112 and the reference cavity 113, thereby improving the consistency of the gas pressure in the test cavity 112 and the reference cavity 113, and further improving the accuracy of the air tightness detection.

[0067] In some embodiments, referring to Figure 3 As shown in the figure, the valve body 110 can include a main body part 1101, a cover plate 1102 and a first isolation part 160. The cover plate 1102 is arranged on one side of the main body part 1101 and cooperates with the main body part 1101 to define a receiving cavity. The first isolation part 160 is arranged in the receiving cavity and separates the working cavity 111, the test cavity 112 and the reference cavity 113. The third gas inlet passage 161 and the fourth gas inlet passage 162 pass through the first isolation part 160.

[0068] In this embodiment, in order to facilitate installation and manufacturing, the valve body 110 can not adopt an integrated structure, but is assembled by the main body part 1101, the cover plate 1102 and the first isolation part 160. Of course, it can be understood that the main body part 1101 can also be arranged in an integrated structure with the first isolation part 160. The mechanism of the valve body 110 is not limited to the above examples. Under the inspiration of the technical essence of the embodiments of the present application, those skilled in the art can also make other changes. However, as long as the functions and effects achieved are the same or similar to those of the embodiments of the present application, they should be covered within the protection scope of the embodiments of the present application.

[0069] In this embodiment, the receiving cavity is formed in the interior of the main body part 1101 and the cover plate 1102, and is divided into the pilot cavity 114, the working cavity 111, the test cavity 112 and the reference cavity 113 by the first isolation part 160 and the second isolation part 150.

[0070] In this embodiment, when the air tightness detection valve group 10 is in the isolation state, the slider 120 abuts against the first isolation part 160 to block the third gas inlet passage 161 and the fourth gas inlet passage 162, so that the working cavity 111 is isolated from the test cavity 112 and the reference cavity 113 respectively, and the test cavity 112 and the reference cavity 113 are independent of each other. When the air tightness detection valve group 10 is in the conduction state, the slider 120 is away from the first isolation part 160, and the working cavity 111 is communicated with the reference cavity 113 through the third gas inlet passage 161 and is communicated with the test cavity 112 through the fourth gas inlet passage 162.

[0071] In this embodiment, before testing, the working chamber 111 is connected to both the reference chamber 113 and the test chamber 112, thereby balancing the air pressure between the reference chamber 113 and the test chamber 112. During testing, the test chamber 112 and the reference chamber 113 are made independent of each other. If the test chamber N of the device under test leaks, there will be a pressure difference between the test chamber N of the device under test and the standard chamber M of the standard device. If the test chamber N of the device under test does not leak, there will be no pressure difference between the test chamber N of the device under test and the standard chamber M of the standard device. Therefore, the testing is convenient and accurate.

[0072] like Figure 3 and Figure 5 As shown, Figure 5 This is an enlarged view of the slider 120 in one embodiment of this application. The first pneumatic valve assembly 100 may further include a first elastic element 130, a first isolation portion 160 having a guide groove 163 sandwiched between the test chamber 112 and the reference chamber 113 and extending along a first direction F1, and a slider 120 having a first limiting protrusion 121 extending along the first direction F1, the first limiting protrusion 121 at least partially extending into the guide groove 163, and the first elastic element 130 being disposed between the bottom wall of the guide groove 163 and the slider 120. Thus, when the first pilot valve 700 drives the slider 120 to move along the first direction F1, the first elastic element 130 can provide a buffering force for the slider 120, reducing the impact force on the slider 120 and the portion in contact with the slider 120. Furthermore, the guide groove 163 limits the movement of the slider 120, preventing the slider 120 from tilting during movement and improving the movement accuracy of the slider 120.

[0073] It is understandable that if a single piston 142 is used to directly push the gas, the piston 142 will have a large impact on the valve during the sealing test, resulting in unstable initial pressure difference, low detection accuracy, and the valve core movement without guidance will cause misalignment, which will easily affect the detection accuracy. Moreover, over time, the detection valve will be severely damaged, leading to a decrease in detection accuracy. However, the airtightness detection valve assembly 10 of this application can provide a buffering force to the slider 120 through the first elastic element 130, so that the slider 120 can be buffered during its movement. At the same time, the first pilot valve 700 with a small flow rate has an exhaust buffering effect, which can significantly reduce the risk of collision damage to the slider 120, reduce the impact force on the slider 120 and the parts in contact with the slider 120, and directly and significantly improve the accuracy of airtightness detection. This will help to improve the service life of the airtightness detection valve assembly 10 and its accuracy after long-term use.

[0074] In the embodiment, the guide groove 163 is mainly arranged to accommodate the first elastic member 130, and can guide the slider 120. Compared with no guide groove 163, the guide groove 163 can accommodate the first elastic member 130, limit the first elastic member 130, make the direction of the elastic force provided by the first elastic member 130 more stable, and be beneficial to reducing the size of the air tightness detection valve group 10. The guide groove 163 can also guide the slider 120, increase the stability of the slider 120 blocking the third air inlet channel 161 and the fourth air inlet channel 162, and then be beneficial to improving the air supply stability or air pressure stability in the test cavity 112 and the reference cavity 113, improving the consistency of the air pressure in the test cavity 112 and the reference cavity 113, and further improving the detection stability.

[0075] The shape of the guide groove 163 can be a cylindrical structure to accommodate the first elastic member 130 and the first limiting protrusion 121 of at least part of the slider 120. The shape of the guide groove 163 can be a cylindrical structure with a circular or square cross section or other geometric shapes. The shape of the corresponding first limiting protrusion 121 is opposite to the shape of the guide groove 163, so that they can cooperate with each other. The guide groove 163 can be arranged as a symmetrical structure, and the relative symmetry plane thereof can be the same plane as the relative symmetry plane of the symmetrically arranged test cavity 112 and reference cavity 113, so that the guide groove 163 can provide more stable movement guidance for the slider 120, be beneficial to stable and balanced air supply for the test cavity 112 and the reference cavity 113, and be beneficial to improving the detection precision. The guide groove 163 and the slider 120 can be gap-fitted, and sealed by the corresponding first sealing structure 164, so as to realize the sealing of the guide groove 163 and the smoothness of the guiding movement between the guide groove 163 and the slider 120.

[0076] In the embodiment, because the slider 120 moves, the size of the first limiting protrusion 121 extending into the guide groove 163 gradually increases during the movement of the slider 120 in the first direction F1 away from the pilot cavity 114, and finally all or part of the first limiting protrusion 121 can extend into the guide groove 163, that is, at least part of the second limiting protrusion 122 extends into the guide groove 163. The length of the first limiting protrusion 121 in the first direction F1 should be slightly greater than the stroke of the slider 120 in the first direction F1, so as to prevent the first limiting protrusion 121 from sliding out of the guide groove 163.

[0077] In the embodiment, the first elastic member 130 can refer to the property that an object deforms under the action of an external force and returns to the original size and shape when the external force is removed.

[0078] In some embodiments, referring to Figure 3As shown, the first isolation portion 160 has an abutting bottom wall on one side of the working cavity 111, the abutting bottom wall is a plane, and the third air inlet channel 161 and the fourth air inlet channel 162 are both provided in the abutting bottom wall; when the slider 120 abuts against the abutting bottom wall, it is in a blocking state, and the third air inlet channel 161 and the fourth air inlet channel 162 are respectively blocked with the working cavity 111. When the slider 120 is away from the abutting bottom wall, it is in a conducting state, and the third air inlet channel 161 and the fourth air inlet channel 162 are respectively communicated with the working cavity 111. Thus, through the design that the abutting bottom wall is a plane, the slider 120 can simultaneously cut off the third air inlet channel 161 and the fourth air inlet channel 162, thereby ensuring that the same amount of gas can be introduced into the test cavity 112 and the reference cavity 113 within the same air inlet time, and further improving the accuracy of the air tightness detection.

[0079] In some embodiments, as Figure 3 , the first gas control valve group 100 can further include a first sealing structure 164 provided between the slider 120 and the inner wall of the guide groove 163. The working cavity 111 and the guide groove 163 or the outside are sealed and isolated, which further helps to improve the air tightness in the working cavity 111 and improve the accuracy of the air tightness detection.

[0080] In the present embodiment, the first sealing structure 164 described above can adopt a sealing ring, a labyrinth seal or the like, which can be determined according to actual conditions and is not limited in the present embodiment.

[0081] In some embodiments, a wear-resistant ring can be further provided between the slider 120 and the inner wall of the guide groove 163 to reduce the risk of reduced detection accuracy caused by wear between the slider 120 and the inner wall of the guide groove 163, thereby improving the accuracy of the air tightness detection.

[0082] In some embodiments, as Figure 3 , the valve body 110 can further include a second isolation portion 150 provided in the accommodating cavity and separated between the working cavity 111 and the pilot cavity 114. The second isolation portion 150 has a guide channel 152 penetrating in the first direction F1, the slider 120 has a second limiting protrusion 122 extending in the first direction F1, the piston 142 is connected with the second limiting protrusion 122, the second limiting protrusion 122 at least partially extends into the guide channel 152, the cover plate 1102 is provided with a first channel communicated with the gas outlet end of the first pilot valve 700, and the second isolation portion 150 is provided with a second channel communicated with the pilot cavity 114. The second channel is communicated with the pilot cavity 114, and the first channel and the second channel are communicated to form a second air inlet channel 115.

[0083] In the embodiment, the working cavity 111 and the pilot cavity 114 are separated by the second isolation part 150, so that the pilot gas and the working gas do not interfere with each other. The guide channel 152 can guide the second limiting protrusion 122, thereby improving the moving precision of the slider 120, and further improving the precision of the air tightness detection.

[0084] In the embodiment, during the movement of the slider 120 along the first direction F1 towards the direction close to the pilot cavity 114, the size of the second limiting protrusion 122 gradually increases when extending into the guide channel 152. Finally, the second limiting protrusion 122 can extend into the guide channel 152, or part of the second limiting protrusion 122 can extend into the guide channel 152, that is, at least part of the second limiting protrusion 122 extends into the guide channel 152.

[0085] In the embodiment, the second isolation part 150 can be provided in a split structure with the body part 1101, so as to install the slider 120, and then the second isolation part 150 and the body part 1101 are connected or bonded by other connection structures such as bolts or glue layers, which are not limited herein.

[0086] In some embodiments, the second limiting protrusion 122 and the inner wall of the guide channel 152 are provided with a second sealing structure 151. Part of the slider 120 extends into the pilot cavity 114 and is connected with the piston 142, and is sealed by the second sealing structure 151, thereby improving the sealing performance of the working cavity 111 and the pilot cavity 114, and improving the detection precision of the air tightness detection.

[0087] In some embodiments, the second sealing structure 151 is a guideable ring seal, which can realize the effects of moving guidance and sealing at the same time. Of course, it can also be other possible structures, which can be determined according to actual conditions, and the embodiments of the present application are not limited thereto.

[0088] In some embodiments, as Figure 3 , the first gas control valve group 100 can further include a second elastic member 141, which is arranged between the piston 142 and the cover plate 1102 away from the slider 120. The second elastic member 141 is in a compressed state along the first direction F1, and the elastic force of the second elastic member 141 is greater than the elastic force of the first elastic member 130.

[0089] It can be understood that the second elastic member 141, the piston 142, the slider 120 and the first elastic member 130 are sequentially arranged along the first direction F1. The first elastic member 130 and the second elastic member 141 are both in a compressed state, and the piston 142 and the slider 120 are connected to each other. In this way, when the pilot gas is introduced to move the piston 142 along the first direction F1 away from the slider 120 or towards the second elastic member 141, the slider 120 and the piston 142 can be driven to move towards the second elastic member 141 under the action of the first elastic member 130, so that the slider 120 moves away from the first isolation portion 160, and the slider 120 cannot be blocked in the third air inlet channel 161 and the fourth air inlet channel 162, thereby making the working chamber 111 respectively communicate with the test chamber 112 and the reference chamber 113.

[0090] When the pilot gas is discharged, i.e. when the pilot gas is not introduced, the elastic force of the second elastic member 141 is greater than the elastic force of the first elastic member 130, so that the piston 142 and the slider 120 move along the first direction F1 to the original position, so that the slider 120 moves towards the first isolation portion 160 and abuts against the first isolation portion 160, and continues to be blocked in the third air inlet channel 161 and the fourth air inlet channel 162, thereby making the working chamber 111 respectively communicate with the test chamber 112 and the reference chamber 113.

[0091] In this way, the movement of the slider 120 along the first direction F1 can be realized by the first elastic member 130 and the elastic driving assembly 140. At the same time, the elastic force of the first elastic member 130 and the second elastic member 141 provides a buffer force for the slider 120, and cooperates with the small flow first pilot valve 700 to have an exhaust buffer effect, so that the slider 120 can be buffered during movement, the risk of collision and damage of the slider 120 is reduced, the impact force of the slider 120 and the part in contact with the slider 120 is reduced, which is beneficial to improve the service life and the use precision after long-term use of the air tightness detection valve group 10. At the same time, the buffer effect of the first elastic member 130, the second elastic member 141 and the first pilot valve 700 greatly weakens the pressure difference caused by the impact influence of the movement of the slider 120, and improves the detection precision.

[0092] In this embodiment, the second elastic member 141 can also be in a stretched state along the first direction F1, and correspondingly, the first elastic member 130 can also be in a stretched state, and the stretching force of the first elastic member 130 needs to be greater than the stretching force of the second elastic member 141, so that when the pilot gas is not introduced into the pilot cavity 114, the piston 142 and the slider 120 can be moved along the first direction F1 by the relative force of the first elastic member 130 and the second elastic member 141 or by the stretching force of the first elastic member 130, and the slider 120 blocks the third air inlet channel 161 and the fourth air inlet channel 162. The first elastic member 130 and the second elastic member 141 can also be in other states, for example, the first elastic member 130 can be in a stretched state, and correspondingly, the second elastic member 141 can be in a relaxed or compressed state. For example, the second elastic member 141 can be in a compressed state, and correspondingly, the first elastic member 130 can be in a relaxed or stretched state. Only one of the first elastic member 130 and the second elastic member 141 needs to be able to provide a driving force for the slider 120 and the piston 142 as a whole to move along the first direction F1 towards the test cavity 112 without introducing the pilot gas into the pilot cavity 114, which is not limited herein.

[0093] In some embodiments, each internal device can be placed by directly opening a channel through the side wall of the valve body 110 to improve the convenience of the process. For the risk of air leakage caused by opening a channel through, a sealing member can be provided on the corresponding channel for sealing, which can be determined according to the actual situation, and the present embodiment is not limited thereto.

[0094] In some embodiments, as shown in Figure 3 The test cavity 112 and the reference cavity 113 can be respectively provided with a lock nut joint at one end away from the working cavity 111, so as to connect the air tightness detection valve group 10 with a to-be-tested member through the corresponding lock nut joint of the test cavity 112, and to communicate a to-be-tested cavity N of the to-be-tested member with the test cavity 112. The air tightness detection valve group 10 is connected with a standard member through the corresponding lock nut joint of the reference cavity 113, and a standard cavity M of the standard member is communicated with the reference cavity 113.

[0095] In some embodiments, as shown in Figure 4The airtightness detection valve group 10 of the present application can further comprise a second air control valve group 300 and a second pilot valve 500. The second air control valve group 300 is arranged on the gas passage between the working gas source 400 and the first air control valve group 100. The pilot gas source 600 is connected to the second air control valve group 300 for introducing pilot gas into the second air control valve group 300 to drive the second air control valve group 300 to work. The second pilot valve 500 is arranged on the gas passage between the pilot gas source 600 and the second air control valve group 300. That is, the working gas source 400 is connected to the first gas inlet passage for introducing working gas into the first gas inlet passage, and the second air control valve group 300 can be arranged between the working gas source 400 and the first air control valve group 100. Whether to introduce working gas is controlled by the second air control valve group 300, so that the start of detection can be accurately controlled.

[0096] The pilot gas source 600 is connected to the second air control valve group 300, and the pilot gas source 600 is used to introduce pilot gas into the second air control valve group 300 to drive the second air control valve group 300 to work. It can be understood that the pilot gas can control the switching of the second air control valve group 300 between the three states of gas inlet, gas outlet and closing, wherein the closing state is the state of not inletting gas and not discharging gas. That is, the pilot gas is introduced, and whether the pilot gas flows to the second air control valve group 300 is controlled by the opening and closing of the second pilot valve 500, that is, whether the second air control valve group 300 inlets gas is controlled. If the gas is inletted, the second air control valve group 300 is turned on, and the working gas can smoothly enter the working cavity 111.

[0097] In the present embodiment, the pilot gas source 600 can be multi-purpose, which can introduce pilot gas into the pilot cavity 114 of the first air control valve group 100 to convert the airtightness detection valve group 10 from the state that the working cavity 111 is communicated with the test cavity 112 and the reference cavity 113 to the state that the working cavity 111 is isolated from the test cavity 112 and the reference cavity 113, and can also introduce pilot gas into the second air control valve group 300 to drive the second air control valve group 300 to work or be turned on, so that the working gas enters the working cavity 111 of the first air control valve group 100. This is conducive to improving the integration of the airtightness detection valve group 10 and improving the miniaturized design of the airtightness detection valve group 10. Moreover, the second pilot valve 500 indirectly controls whether the working gas works, which is convenient for the second pilot valve 500 to use a small-power pilot electromagnetic valve as a driving valve, is conducive to reducing the influence of the valve group caused by the temperature rise after long-time use of the electromagnetic valve, and is conducive to improving the detection accuracy.

[0098] In some embodiments, referring to Figure 4 The airtightness detection valve group 10 can further comprise an exhaust pilot valve 800 arranged on the gas passage between the pilot gas source 600 and the second air control valve group 300. The exhaust pilot valve 800 is used to introduce pilot gas into the second air control valve group 300 to drive the second air control valve group 300 to discharge working gas to the outside.

[0099] In the embodiment, the exhaust pilot valve 800 controls whether the second pneumatic valve group 300 exhausts, thereby controlling the working gas to be discharged, and stopping the air tightness detection work. After the detection is completed, the exhaust pilot valve 800 is opened, and the working gas is uniformly discharged. There is no need to separate the exhaust gas, which is beneficial to improve the operation convenience. It can be understood that when the exhaust pilot valve 800 is not powered, the pilot gas enters the pilot chamber 114 and pushes against the piston 142, and when the exhaust pilot valve 800 is powered, the pilot gas in the pilot chamber 114 is exhausted to the outside. Because a small flow pilot valve is used, the exhaust is relatively slow, so that the slider 120 will only press down the seal when the gas pressure is less than the force difference of the two elastic members. Moreover, the exhaust pilot valve 800 uses a small flow pilot valve, which increases the exhaust buffering effect, thereby further protecting the valve body and improving the accuracy of the air tightness detection.

[0100] In some embodiments, as Figure 4 , the air tightness detection valve group 10 can further include a differential pressure sensor 200 and a pressure sensor 900. The differential pressure sensor 200 can include a first detection end and a second detection end. The first detection end is arranged on the gas passage between the test chamber 112 and the to-be-detected chamber N of the to-be-detected member, and the second detection end is arranged on the gas passage between the reference chamber 113 and the standard chamber M of the standard member. The pressure sensor 900 is arranged on the gas passage between the first pneumatic valve group 100 and the second pneumatic valve group 300, so as to monitor the working gas pressure, facilitate real-time monitoring of the working chamber 111 pressure, facilitate troubleshooting, and calculate the charging pressure time according to the monitored working gas pressure. The side wall of the valve body 110 is provided with a through hole for connecting the pressure sensor 900. In this way, the pressure sensor 900 does not need to be additionally arranged on the channel, which is beneficial to improve the integration of the air tightness detection valve group 10 and realize the miniaturization design of the air tightness detection valve group 10.

[0101] In some embodiments, as Figure 3 , the air tightness detection valve group 10 can further include an exhaust passage 170 for connecting the pilot chamber 114 and the outside. The first pilot valve 700 is arranged on the exhaust passage 170, so as to control the exhaust of the pilot gas in the pilot chamber 114 through the first pilot valve 700.

[0102] In some embodiments, continuing to refer to Figure 2As shown, the first pneumatic valve group 100 is arranged on the second pneumatic valve group 300 and located on one side of the second pneumatic valve group 300 along the second direction F2, the first pilot valve 700 is arranged on the outer side wall of the first pneumatic valve group 100 and located on one side of the first pneumatic valve group 100 along the first direction F1, the second pilot valve 500 and the exhaust pilot valve 800 are both arranged on one side of the second pneumatic valve group 300 along the first direction F1 and both located on the second pneumatic valve group 300. It can be seen that the airtightness detection valve group 10 of the present application highly integrates the first pneumatic valve group 100, the second pneumatic valve group 300, the second pilot valve 500, the first pilot valve 700 and the exhaust pilot valve 800, which is conducive to reducing the volume of the airtightness detection valve group 10 and realizing the miniaturization design of the airtightness detection valve group 10.

[0103] In some embodiments, the detection steps using the airtightness detection valve group 10 can include:

[0104] S1, opening the pilot source and the working gas source 400 to fill the pilot gas and the working gas into the airtightness detection valve group 10.

[0105] It can be understood that the first pilot valve 700 is in a normally open state, that is, when in use, the first pilot valve 700 is in a pass-through state without being powered on, and does not need to be intentionally opened. If it needs to be closed, the second pilot valve 500 is powered on or said to be powered on, at this time, the pilot gas in the pilot chamber 114 is exhausted to the atmosphere, and the pilot gas is prevented from entering the pilot chamber 114.

[0106] In this way, when the pilot gas source 600 is opened, the pilot gas directly enters the second gas inlet channel 115 through the normally open first pilot valve 700, and the working chamber 111, the test chamber 112 and the reference chamber 113 are usually in a conductive state. Only when the first pilot valve 700 is powered on, the working chamber 111, the test chamber 112 and the reference chamber 113 are in an isolated state. In this way, the operation steps are saved, and the use convenience is improved. At the same time, the first pilot valve 700 is in a normally open state when powered off, which is conducive to reducing the influence of the first pilot valve 700 due to temperature rise after long-term use on detection accuracy, and improving detection accuracy.

[0107] After the pilot gas is filled, the pilot gas enters the second pneumatic valve group 300 through the second pilot valve 500, drives the second pneumatic valve group 300 to be in an open state, and makes the working gas source 400 and the second pneumatic valve group 300 of the first pneumatic valve group 100 conductive. At the same time, the first pilot valve 700 is in a normally open state, the pilot gas automatically enters the pilot chamber 114, drives the piston 142 to move along the first direction F1, and under the action of the first elastic member 130 and the second elastic member 141, the sliding block 120 moves along the first direction F1, so that the working chamber 111, the test chamber 112 and the reference chamber 113 are in a conductive state.

[0108] And because the second gas control valve group 300 is in an open state at this time, the working gas can directly pass through the second gas control valve group 300 into the working cavity 111, and then into the test cavity 112 and the reference cavity 113 in communication with the working cavity 111, to inflate the test cavity 112 and the reference cavity 113, and the to-be-tested cavity N and the standard cavity M.

[0109] S2, pressure maintaining, the second pilot valve 500 controls the pilot gas not to enter the second gas control valve group 300, so that the second gas control valve group 300 controls the working gas not to be introduced into the working cavity 111. At this time, the first pilot valve 700 is always on, and the working cavity 111, the test cavity 112 and the reference cavity 113 are still in a communication state, and a first preset time is continued to improve the stability of the test cavity 112 and the reference cavity 113, and to reduce the influence of temperature changes and the like on the pressure of the test cavity 112 and the reference cavity 113, thereby improving the detection accuracy. The time of inflating the working gas and the first preset time of pressure maintaining can be determined according to the size of the to-be-tested cavity N of the to-be-tested piece, and can be 5 seconds.

[0110] S3, detection. The first pilot valve 700 is powered on, the pilot gas is stopped from being introduced into the pilot cavity 114, the working cavity 111, the test cavity 112 and the reference cavity 113 are in an isolated state, and then the test cavity 112 and the reference cavity 113 are independent of each other. After a second preset time, the pressure difference sensor 200 is read to see if there is a pressure difference between the test cavity 112 and the reference cavity 113. If there is no pressure difference between the standard cavity M of the standard piece and the to-be-tested cavity N of the to-be-tested piece, it means that the to-be-tested cavity N of the to-be-tested piece does not leak and is well sealed. If there is a pressure difference, it means that the to-be-tested cavity N of the to-be-tested piece leaks and the seal is damaged.

[0111] S4, exhaust and power off. After the detection is completed, the exhaust pilot valve 800 is powered on to drive the second gas control valve group 300 to exhaust to the outside, and the exhaust pilot valve 800 is powered off after a predetermined exhaust time to complete the exhaust. The first pilot valve 700 is also powered off to complete the detection.

[0112] The air tightness detection valve group 10 of the present application can provide a buffer force to the slider 120 through the design of the first elastic member 130, the second elastic member 141, the first pilot valve 700 and the exhaust pilot valve 800, so that the slider 120 can be buffered during movement, the risk of collision and damage of the slider 120 is reduced, the impact force of the slider 120 and the part in contact with the slider 120 is reduced, and the service life and the use accuracy after long-term use of the air tightness detection valve group 10 are improved.

[0113] It can be understood that the impact of the movement of the slider 120 has a direct impact on the pressure fluctuation of the test cavity 112 and the reference cavity 113, especially when the user's test cavity 112 and the reference cavity 113 have different volumes, the impact of this impact will be amplified. For users, it is still possible to perform accurate detection when the volumes of the test cavity 112 and the reference cavity 113 are different, which means that a standard test cavity 112 can be used to detect a variety of workpieces within a certain range, saving costs, so reducing the impact can directly improve the accuracy and is very critical.

[0114] And the application greatly weakens the pressure difference caused by the impact of the movement of the slider 120 through the buffering effect of the first elastic member 130 and the second elastic member 141, thereby improving the detection accuracy. The first pilot valve 700 with small flow has the effect of exhaust buffering, thereby improving the accuracy of the air tightness detection. At the same time, by using the pilot valve body to set the exhaust pilot valve 800, it has a small exhaust flow, which increases the effect of exhaust buffering, thereby further protecting the valve body and improving the accuracy of the air tightness detection.

[0115] The technical features of the above-described embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described, but as long as the combinations of the technical features do not exist contradictory, they should be considered as the scope of the present application.

[0116] The above-described embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A hermeticity detection valve set, characterized by, The air tightness detection valve group comprises a pilot gas source, a working gas source, a first gas control valve group and a first pilot valve, the pilot gas source is used for air supply to the air inlet end of the first pilot valve, and the working gas source is used for air supply to the air inlet end of the first gas control valve group; The first gas control valve group comprises a valve body, a piston and a slider, the valve body has a pilot cavity, a working cavity, a test cavity and a reference cavity, the valve body is provided with a first air inlet channel communicating the working cavity and the working gas source, and the valve body is provided with a second air inlet channel communicating the first pilot valve and the pilot cavity; the test cavity has a third air inlet channel communicating the working cavity, and the reference cavity has a fourth air inlet channel communicating the working cavity; The slider is connected with the piston, the piston is arranged in the pilot cavity, the slider is arranged in the working cavity, the piston is fixedly connected with the slider, and the slider is arranged on the same side of the third air inlet channel and the fourth air inlet channel; the first pilot valve is used for air supply or discharge into the pilot cavity through the second air inlet channel to push the piston and drive the slider to move in the working cavity in a first direction, so as to synchronously move away from or abut against the third air inlet channel and the fourth air inlet channel, and control the test cavity and the reference cavity to be communicated or blocked with the working cavity.

2. The leak test valve train of claim 1, wherein, The first pilot valve is a balanced pilot valve.

3. The leak test valve train of claim 1, wherein, The test cavity and the reference cavity are symmetrically arranged, and the slider is symmetrically arranged.

4. The leak test valve train of claim 1, wherein, The valve body comprises a main body part, a cover plate and a first isolation part, the cover plate is arranged on one side of the main body part, and together with the main body part, limits a containing cavity, the first isolation part is arranged in the containing cavity and is arranged between the working cavity, the test cavity and the reference cavity, and the third air inlet channel and the fourth air inlet channel are both arranged in the first isolation part; The first gas control valve group further comprises a first elastic member, the first isolation part has a guide groove arranged between the test cavity and the reference cavity and extending in the first direction, the slider has a first limiting protrusion extending in the first direction, the first limiting protrusion at least partially extends into the guide groove, and the first elastic member is arranged between the bottom wall of the guide groove and the slider.

5. The leak test valve train of claim 4 wherein, One side of the first isolation part towards the working cavity has an abutting bottom wall, the abutting bottom wall is a plane, and the third air inlet channel and the fourth air inlet channel are both arranged in the abutting bottom wall; when the slider abuts against the abutting bottom wall, the slider is in a blocking state, and the third air inlet channel and the fourth air inlet channel are respectively blocked with the working cavity; when the slider moves away from the abutting bottom wall, the slider is in a communicating state, and the third air inlet channel and the fourth air inlet channel are respectively communicated with the working cavity.

6. The leak test valve train of claim 4 wherein, The first gas control valve group further comprises a first sealing structure, and the first sealing structure is arranged between the slider and the inner wall of the guide groove.

7. The leak test valve train of claim 4 wherein, The valve body further comprises a second isolation part arranged in the accommodating cavity and arranged between the working cavity and the pilot cavity, the second isolation part has a guide channel penetrating in the first direction, the slider has a second limiting protrusion extending in the first direction, the piston is connected with the second limiting protrusion, and the second limiting protrusion at least partially extends into the guide channel; The cover plate is provided with a first channel communicated with the first pilot valve gas outlet, the second isolation part is provided with a second channel communicated with the pilot cavity, and the first channel and the second channel are communicated to form the second gas inlet channel; The second limiting protrusion and the inner wall of the guide channel are provided with a second sealing structure.

8. The leak test valve train of claim 7, wherein, The first pneumatic valve group further comprises a second elastic member arranged between the side of the piston away from the slider and the cover plate; The second elastic member is in a compressed state in the first direction, and the elastic force of the second elastic member is greater than the elastic force of the first elastic member.

9. The leak test valve train of claim 1, wherein, The air tightness detection valve group further comprises a second pneumatic valve group and a second pilot valve, the second pneumatic valve group is arranged on the gas channel between the working gas source and the first pneumatic valve group; The pilot gas source is communicated with the second pneumatic valve group for introducing pilot gas into the second pneumatic valve group to drive the second pneumatic valve group to work; The second pilot valve is arranged on the gas channel between the pilot gas source and the second pneumatic valve group.

10. The leak test valve train of claim 9, wherein, The air tightness detection valve group further comprises an exhaust pilot valve arranged on the gas channel between the pilot gas source and the second pneumatic valve group, the exhaust pilot valve is used for introducing pilot gas into the second pneumatic valve group to drive the second pneumatic valve group to exhaust working gas to the outside.

11. The leak test valve train of claim 9 wherein, The air tightness detection valve group further comprises a differential pressure sensor and a pressure sensor, the differential pressure sensor comprises a first detection end and a second detection end, the first detection end is arranged on the gas channel between the test cavity and the cavity to be detected, and the second detection end is arranged on the gas channel between the reference cavity and the standard cavity; the pressure sensor is arranged on the gas channel between the first pneumatic valve group and the second pneumatic valve group.

12. The leak test valve train of claim 1, wherein, The air tightness detection valve group further comprises an exhaust channel communicated with the pilot cavity and the outside, and the first pilot valve is arranged on the exhaust channel.

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