Air tightness detection equipment of valve body and use method thereof

Abstract

The invention discloses airtightness detection equipment of a valve body and a use method thereof, the airtightness detection equipment of the valve body comprises a rack and a detection mechanism, the detection mechanism comprises a static chuck and a movable chuck, and the static chuck is provided with an air outlet pipe, an infrared monitoring probe and an air flow meter; the movable chuck is provided with an air inlet pipe, an electronic barometer, a heating cavity and an air inlet switch and is connected with an external air compressor, the air inlet pipe further comprises an upper-layer pipeline and a lower-layer pipeline, the air inlet switch is communicated with the lower-layer pipeline, and the heating cavity is communicated with the upper-layer pipeline; two supporting frames are further arranged on the two sides of the static chuck, and an infrared imaging display screen and a control box are further arranged on the machine frame. According to the air tightness detection device, manual air tightness judgment is not needed, the position where an unqualified product leaks can be displayed and recorded, and assistance is provided for product upgrading and process improvement; and heat preservation can be carried out on gas in the valve body, the influence of temperature change on gas pressure is prevented, and the detection accuracy is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of valve body detection, and more specifically to an air tightness detection device for a valve body and a use method thereof. Background Art

[0002] Traditionally, water testing is used to test the air tightness of valve bodies. That is, compressed gas is introduced into the cavity of the valve body and then the valve body is immersed in water to observe the bubbles generated in the water to determine whether the air tightness of the valve body is qualified. This method will affect the appearance of the valve body; secondly, the detection efficiency is low and the labor intensity of the inspectors is high; thirdly, the detection is highly subjective and prone to misjudgment.

[0003] At present, a Chinese patent with the announcement number CN102384825B discloses a valve body air tightness detection device, which includes a shell and at least one detection mechanism, the detection mechanism includes a static chuck and a dynamic chuck, the dynamic chuck and the static chuck are arranged opposite to each other, the end faces of the dynamic chuck and the static chuck are both provided with rubber sealing pads, the static chuck is fixed on the shell, the dynamic chuck is fixed on the piston rod of a cylinder, the cylinder is fixed on the shell and connected to the air source through an electromagnetic reversing valve; an air outlet pipe is provided in the middle of the static chuck, one end of the air outlet pipe is located in the middle of the end face of the static chuck, and the other end is connected to a water tank arranged on the shell, and a valve body is provided in the middle of the air outlet pipe; an air inlet pipe is provided in the middle of the dynamic chuck, one end of the air inlet pipe is located in the middle of the end face of the dynamic chuck, and the other end is connected to the air source through another electromagnetic reversing valve, and a pressure gauge is connected to the air inlet pipe; it can detect the cut-off performance of the valve body and the air tightness of the cavity when the valve body to be tested is not immersed in water, and effectively protect the appearance of the valve body.

[0004] However, there are still some problems, such as the lack of a fixing mechanism for the valve body, and only the use of dynamic and static chucks to fix the valve body, which is prone to installation dislocation, resulting in gas leakage at the connection of the valve body, resulting in unstable air pressure in the valve and poor detection effect; when detecting the airtight performance, the method of observing bubbles is still used, the labor intensity of the detection personnel is still large, and long-term observation is required. The subjectivity is also strong, and only qualitative judgment can be made on whether it is qualified, and the specific leakage amount cannot be quantitatively detected; and in the actual production process, the airtightness detection of the valve body is not only used to determine whether the valve body is qualified, but also to help the subsequent valve body product upgrade and manufacturing process improvement. The patented technical solution with announcement number CN102384825B cannot well determine where the unqualified product leaks, so that engineers need to repeat the detection of unqualified products when upgrading and improving the product to determine where most of the unqualified products have problems, so as to improve the product structure or change the local manufacturing method. Therefore, there is an urgent need for a valve body airtightness detection device that detects and records the leakage position of the unqualified valve body while detecting whether the valve body is qualified, so as to provide assistance to subsequent engineers in product upgrades and process improvements. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a valve body air tightness detection device and a method of using the same, which does not require manual air tightness judgment and can also display where the unqualified product leaks and record it, thereby providing assistance for product upgrades and process improvements; and can also insulate the gas in the valve body to prevent temperature changes from affecting the air pressure, thereby increasing detection accuracy.

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an air tightness detection device for a valve body, comprising a frame and a detection mechanism, the detection mechanism comprising a relatively arranged static chuck and a dynamic chuck, the static chuck being fixedly connected to the frame, the dynamic chuck being provided with a cylinder and being slidably connected to the frame, characterized in that: an air outlet pipe is provided in the static chuck, one end of the air outlet pipe extends out of the end face of the static chuck, and is provided with an infrared monitoring probe, and the other end is connected to an air flow meter; an air inlet pipe and an electronic pressure gauge are provided in the dynamic chuck, one end of the air inlet pipe extends out of the end face of the dynamic chuck, and the other end is provided with a heating chamber and an air inlet switch and is connected to an external air compressor, the static chuck and the dynamic chuck are used to clamp the valve body to be tested;

[0007] The air inlet pipe also includes an upper pipe and a lower pipe, the upper pipe and the lower pipe are located in a section of the air inlet pipe from the air inlet switch to the end surface of the dynamic clamp, the air inlet switch is connected to the lower pipe, and the heating chamber is connected to the upper pipe;

[0008] Two support frames slidably connected to the frame are symmetrically arranged on both sides of the stationary clamp, and the support frames are used to support the valve body to be tested so that the valve body to be tested is aligned with the stationary clamp and the dynamic clamp;

[0009] The frame is also provided with an infrared imaging display screen, which is electrically connected to the infrared monitoring probe;

[0010] The frame is also provided with a control box, which is electrically connected to the electronic barometer, the air flow meter and the infrared imaging display screen.

[0011] The present invention is further configured as follows: a single chip microcomputer and a storage hard disk are arranged in the control box; the single chip microcomputer cooperates with an electronic barometer and an air flow meter to analyze the air flow leakage per unit time under specified air pressure conditions to determine whether the valve body to be tested is qualified.

[0012] The present invention is further configured as follows: a video recording module is provided in the infrared imaging display screen, the single chip microcomputer controls the start, shut down and video recording functions of the infrared imaging display screen, and the storage hard disk is used to store video recording information.

[0013] The present invention is further configured as follows: a central gear hinged to the frame is provided in the middle position of the two support frames, racks meshing with the central gear are respectively provided on the two support frames, and the two racks are respectively meshed with two sides of the central gear.

[0014] The present invention is further configured such that the clamping end faces of the static chuck and the dynamic chuck are both provided with rubber sealing pads.

[0015] The present invention is further configured as follows: a pressure sensor electrically connected to a control box is provided on the support frame, and the central gear is connected to a servo motor electrically connected to the control box.

[0016] The present invention is further configured as follows: a heating plate, an air suction fan and an air outlet fan are arranged in the heating chamber, and the heating plate is arranged between the air suction fan and the air outlet fan.

[0017] The present invention is further configured as follows: a qualified indicator light is also provided on the control box.

[0018] A method for detecting air tightness of a valve body comprises the following steps:

[0019] S1. Place the valve body to be tested on the testing mechanism. At this time, the pressure sensor detects the valve body to be tested and sends a signal to the single chip microcomputer to control the servo motor to drive the central gear to rotate, so that the racks on both sides move and the support frame moves toward each other. During the process, align the center of the valve body to be tested with the center of the static chuck and the dynamic chuck;

[0020] S2. The dynamic chuck moves toward the static chuck driven by the cylinder to firmly clamp the valve body to be tested, and the rubber sealing gasket seals the end surface of the valve body to be tested and the chuck;

[0021] S3. Switch the valve body to be tested to the cut-off state, turn on the air inlet switch, and use the external air compressor to inflate the valve body through the air inlet pipe. At the same time, observe the pressure value on the electronic pressure gauge. When the pressure value reaches the specified pressure, turn off the air inlet switch.

[0022] S4, the single chip microcomputer in the control box controls the start and shut down of the heating plate, the air suction fan and the air outlet fan inside the heating chamber to keep the gas temperature in the valve body constant, thereby keeping the gas pressure in the valve body constant;

[0023] S5, the infrared monitoring probe monitors the valve body in real time and sends the image information to the infrared imaging display screen for display and recording;

[0024] S6. The air flow meter detects gas leakage at the outlet and returns the value to the single-chip microcomputer. The single-chip microcomputer compares the returned value with the set value. When the returned value is less than the set value, it means that the valve body is qualified and the qualified indicator light shows green. When the returned value is greater than the set value, it means that the valve body is unqualified and the qualified indicator light shows red. The unqualified video information is stored in the storage hard disk.

[0025] In summary, the present invention has the following beneficial effects:

[0026] The present invention quantitatively analyzes the air tightness of the valve body by setting an air flow meter and an electronic barometer, and judges whether the air tightness of the valve body is qualified by the returned numerical value, which reduces the labor intensity and eliminates the misjudgment that may be caused by the subjective judgment of the detection personnel; and the present invention is also provided with an infrared monitoring probe and a heating chamber. When detecting the air tightness, the infrared image of the valve core in the valve body is fed back in real time by the infrared monitoring probe, displayed on the infrared imaging display screen, and recorded. When the detected valve body is unqualified, the image sent back by the infrared monitoring probe can clearly show where the gas leakage occurs in the valve body, and the video is saved for subsequent viewing. Through the above-mentioned improvements, not only can the air tightness of the valve body be detected, but also the problem of the unqualified product can be accurately detected, and the video can be saved. In this way, when the engineer performs subsequent product upgrades and process improvements, the places where problems are prone to occur in the unqualified valve body can be improved in a targeted manner, which solves the problem that the prior art can only judge whether it is qualified but cannot well judge where the unqualified product leaks, so that the engineer needs to repeat the detection of the unqualified product when upgrading and improving the product.

[0027] At the same time, the existing detection process is generally to close the valve body, use an air compressor to pass gas of a certain pressure on the air inlet side, close the air inlet switch, let the high-pressure gas stay in the valve body for a long time, and detect whether there is gas leakage on the other side to determine whether the air tightness is qualified. The most easily overlooked point in this process is the effect of temperature on the gas pressure in the closed environment in the valve body. Because the air compressor compresses the air, according to the first law of thermodynamics, the temperature of the compressed air will rise when doing work, so the temperature of the gas discharged by the air compressor is relatively high. In the existing scheme, after the gas is passed into the valve body to the specified pressure, The air intake switch will be closed to start detection. However, after a period of time, the heat is dissipated and the gas temperature drops, causing the air pressure in the valve body to drop. The change in the precondition of the air pressure causes the subsequent detection results to be inaccurate. The present invention divides the air intake pipe into an upper pipe and a lower pipe. The lower pipe is normally connected to the external air compressor and the air intake switch, and the upper pipe is connected to the heating chamber. The gas in the valve body is circulated and heated to keep the temperature and air pressure constant, so that the detection result is more accurate. Maintaining a higher gas temperature can also make the image information detected by the infrared monitoring probe clearer, which is convenient for personnel to identify the location of the leak. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the overall structure of this embodiment;

[0029] Figure 2 Schematic diagram of the internal structure of the heating chamber and the air intake pipe of this embodiment;

[0030] Figure 3 Schematic diagram of the motion structure of the support frame in this embodiment.

[0031] Figure numerals: 1. frame; 101. cylinder; 2. detection mechanism; 201. static chuck; 202. dynamic chuck; 3. outlet pipe; 302. air flow meter; 4. inlet pipe; 401. electronic barometer; 402. inlet switch; 403. upper pipeline; 404. lower pipeline; 5. support frame; 501. pressure sensor; 502. servo motor; 6. infrared monitoring probe; 601. infrared imaging display screen; 7. control box; 701. qualified indicator light; 8. center gear; 9. rack; 10. rubber sealing pad; 11. heating chamber; 1101. heating plate; 1102. suction fan; 1103. outlet fan. DETAILED DESCRIPTION

[0032] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0033] This embodiment discloses a valve body air tightness detection device, referring to Figure 1When the valve body to be tested is placed between the static chuck 201 and the dynamic chuck 202, the pressure sensor 501 at the bottom will be triggered. After the pressure sensor 501 is triggered, the single chip microcomputer in the control box 7 will control the servo motor 502 to start, driving the central gear 8 to rotate. The specific structure of the central gear 8 and the rack 9 is as follows: Figure 3 As shown, the rotation of the central gear 8 drives the racks 9 meshing with it on both sides to move, pull the support frame 5 inward, and the two support frames move toward each other to clamp the valve body, so that the center of the valve body is aligned with the center of the static clamp 201 and the dynamic clamp 202. In this way, after the dynamic clamp 202 clamps the valve body to be tested under the drive of the cylinder 101, the air pipes protruding from the end faces of the dynamic clamp 202 and the static clamp 201 can extend into the interior of the valve body, which is convenient for subsequent testing;

[0034] After the valve body to be tested is installed, the valve body is switched to the cut-off state, and then the air inlet switch 402 is turned on. The external air compressor inflates the valve body through the air inlet pipe 4. After observing that the electronic barometer 401 reaches the set pressure, the air inlet switch 402 is turned off to keep the high pressure environment inside the valve body for a certain period of time. At the same time, the single chip starts the heating plate 1101, the air inlet fan 1102 and the air outlet fan 1103 in the heating chamber 11. The structure in the heating chamber 11 is as shown in FIG. Figure 2 As shown, the heating chamber 11 cooperates with the double-layer pipe structure in the air inlet pipe 4, and is connected to the interior of the valve body with its upper pipe 403. The air inlet fan 1102 first guides the gas in the valve body into the heating chamber 11, heats the gas through the heating plate 1101, and then discharges the gas back into the valve body through the air outlet fan 1103. The heating plates 1101 are arranged in multiple groups, and gaps are left for gas to pass through. The two fans work alternately to ensure that the gas can pass through the heating plates and be fully heated. Through this cyclic heating method, the gas delivered by the air compressor maintains the original high temperature, and the air pressure in the valve body will not drop due to heat dissipation and temperature drop, thereby improving the accuracy of the detection result; an infrared monitoring probe 6 is arranged on the air outlet pipe 3 on the other side of the valve body to detect the airtightness of the valve body. The inside of the valve body is monitored all the time, and the internal image is displayed and recorded through the infrared imaging display screen 601. In addition, the air flow meter 302 is also detecting whether there is a gas leak and how much the leakage is. If the air flow meter 302 does not detect gas leakage during the pressure-maintaining time of the valve body to be tested, or the leakage is within the qualified range, the single-chip microcomputer determines that the valve body is qualified, and the qualified indicator light 701 is displayed as green. If the air flow meter 302 detects a gas leakage greater than the specified value, the single-chip microcomputer determines that the valve body is unqualified, and the qualified indicator light is displayed as red. The video information returned by the infrared monitoring probe 6 on the infrared imaging display screen 601 is saved in the storage hard disk, which is convenient for subsequent engineers to analyze unqualified products.

[0035] The specific detection steps of this embodiment are as follows:

[0036] S1. Place the valve body to be tested on the detection mechanism 2. At this time, the pressure sensor 501 detects the valve body to be tested, sends a signal to the single chip microcomputer, controls the servo motor 502 to drive the central gear 8 to rotate, so that the racks 9 on both sides move, and move the support frame 5 towards each other. During the process, the center of the valve body to be tested is aligned with the center of the static chuck 201 and the dynamic chuck 202; the installation position of the valve body is controlled by the support frame 5 to ensure that it is aligned with the center of the chuck each time it is installed, so as to ensure the sealing of the installation end face, making the airtightness detection more accurate. At the same time, the infrared probe 6 monitors the same area each time, which is convenient for comparison of the detection results;

[0037] S2, the dynamic chuck 202 moves toward the side of the static chuck 201 driven by the cylinder 101, firmly clamps the valve body to be tested, and the rubber sealing gasket 10 seals the end surface of the valve body to be tested and the chuck;

[0038] S3, switch the valve body to be tested to the cut-off state, open the air inlet switch 402, and use the external air compressor to inflate the valve body through the air inlet pipe 4, while observing the pressure value on the electronic pressure gauge 401. When the pressure value reaches the specified pressure, close the air inlet switch 402; after closing the air inlet switch 402, the gas inside the valve body to be tested is isolated from the outside and is in a pressure-maintaining state, which is convenient for subsequent testing;

[0039] S4, the single chip microcomputer in the control box 7 controls the start and stop of the heating plate 1101, the air suction fan 1102 and the air outlet fan 1103 inside the heating chamber 11, so as to keep the gas temperature in the valve body constant, and then keep the gas pressure in the valve body constant; the gas in the closed environment inside the valve body is circulated and heated by the heating chamber 11 to keep its temperature and pressure constant, and the internal air pressure will not change due to the heat dissipated from the surface of the valve body, thereby improving the accuracy of air tightness detection;

[0040] S5. The infrared monitoring probe 6 monitors the inside of the valve body in real time and sends the image information to the infrared imaging display screen 601 for display and recording; the inspector can check the inside of the valve body through the infrared monitoring display screen 601 during the inspection to intuitively see whether there is any gas leakage in the valve body.

[0041] S6. The air flow meter 302 detects the gas leakage at the outlet and returns the value to the single-chip microcomputer. The single-chip microcomputer compares the returned value with the set value. When the returned value is less than the set value, it means that the valve body is qualified, and the qualified indicator light 701 displays a green light. When the returned value is greater than the set value, it means that the valve body is unqualified, and the qualified indicator light 701 displays a red light. The unqualified video information is stored in the storage hard disk. When engineers perform product upgrades and process improvements, they can view the video information of unqualified products, and then determine where the unqualified products are leaking, which provides assistance for their product upgrades and process improvements.

[0042] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the design concept of the present invention should be included in the protection scope of the present invention.

Claims

1. A valve body air tightness detection device, comprising a frame (1) and a detection mechanism (2), wherein the detection mechanism (2) comprises a stationary chuck (201) and a dynamic chuck (202) arranged opposite to each other, wherein the stationary chuck (201) is fixedly connected to the frame (1), and the dynamic chuck (202) is provided with a cylinder (101) and is slidably connected to the frame (1). Features: The static chuck (201) is provided with an air outlet pipe (3), one end of which extends out of the end surface of the static chuck (201) and is provided with an infrared monitoring probe (6), and the other end is connected to an air flow meter (302); the dynamic chuck (202) is provided with an air inlet pipe (4) and an electronic barometer (401), one end of which extends out of the end surface of the dynamic chuck (202), and the other end is provided with a heating chamber (11) and an air inlet switch (402) and is connected to an external air compressor, and the static chuck (3) and the dynamic chuck (4) are used to clamp the valve body to be tested; The air inlet pipe (4) further comprises an upper pipe (403) and a lower pipe (404), wherein the upper pipe (403) and the lower pipe (404) are located in a section of the air inlet pipe (4) from the air inlet switch (402) to the end surface of the moving chuck (202), the air inlet switch (402) is in communication with the lower pipe (404), and the heating chamber (11) is in communication with the upper pipe (403); Two support frames (5) slidably connected to the frame (1) are symmetrically arranged on both sides of the stationary chuck (3), and the support frames (5) are used to support the valve body to be tested so that the valve body to be tested is aligned with the stationary chuck (3) and the dynamic chuck (4); an infrared imaging display screen (601) is also arranged on the frame (1), and the infrared imaging display screen (601) is electrically connected to the infrared monitoring probe (6); The frame (1) is also provided with a control box (7), and the control box (7) is electrically connected to the electronic barometer, the air flow meter (302), and the infrared imaging display screen (601).

2. The air tightness detection device of a valve body according to claim 1, Features: The control box (7) is provided with a single-chip microcomputer and a storage hard disk, and the single-chip microcomputer cooperates with an electronic barometer (401) and an air flow meter (302).

3. The air tightness detection device of a valve body according to claim 2, Features: A video recording module is provided in the infrared imaging display screen (601); the single chip microcomputer controls the start-up, shutdown and video recording functions of the infrared imaging display screen (601); and the storage hard disk is used to store video recording information.

4. The air tightness detection device for a valve body according to claim 1, Features: A central gear (8) hinged to the frame (1) is arranged in the middle of the two support frames (5), and racks (9) meshing with the central gear (8) are respectively arranged on the two support frames (5), and the two racks (9) are respectively meshed with two sides of the central gear (8).

5. The air tightness detection device for a valve body according to claim 1, Features: The clamping end surfaces of the static clamp (201) and the dynamic clamp (202) are both provided with rubber sealing pads (10).

6. The air tightness detection device for a valve body according to claim 4, Features: The support frame (5) is provided with a pressure sensor (501) electrically connected to the control box (7), and the central gear (8) is connected to a servo motor (502) electrically connected to the control box (7).

7. The air tightness detection device for a valve body according to claim 1, Features: A heating plate (1101), an air suction fan (1102) and an air outlet fan (1103) are arranged in the heating chamber (11), and the heating plate (1101) is arranged between the air suction fan (1102) and the air outlet fan (1103).

8. The air tightness detection device for a valve body according to claim 1, Features: The control box (7) is also provided with a qualified indicator light (701).

9. A method for detecting the air tightness of a valve body, Features: The following steps are included: S1. The valve body to be tested is placed on the testing mechanism (2). At this time, the pressure sensor (501) detects the valve body to be tested and sends a signal to the single chip microcomputer to control the servo motor (502) to drive the central gear (8) to rotate, so that the racks (9) on both sides are activated and the support frame (5) is moved toward each other. During the process, the center of the valve body to be tested is aligned with the center of the static chuck (201) and the center of the dynamic chuck (202); S2, the movable chuck (202) moves toward the side of the static chuck (201) driven by the cylinder (101) to firmly clamp the valve body to be tested, and the rubber sealing gasket (10) seals the end surface of the valve body to be tested and the chuck; S3, switch the valve body to be tested to the cut-off state, open the air inlet switch (402), and use the external air compressor to inflate the valve body through the air inlet pipe (4), while observing the pressure value on the electronic pressure gauge (401). When the pressure value reaches the specified pressure, close the air inlet switch (402); S4, the single chip microcomputer in the control box (7) controls the start and stop of the heating plate (1101), the air suction fan (1102) and the air outlet fan (1103) inside the heating chamber (11), so as to keep the gas temperature in the valve body constant, thereby keeping the gas pressure in the valve body constant; S5, the infrared monitoring probe (6) monitors the valve body in real time and sends the image information to the infrared imaging display screen (601) for display and recording; S6. The air flow meter (302) detects the gas leakage at the outlet and returns the value to the single chip microcomputer, which compares the returned value with the set value. When the returned value is less than the set value, it means that the valve body is qualified, and the qualified indicator light (701) displays a green light. When the returned value is greater than the set value, it means that the valve body is unqualified, and the qualified indicator light (701) displays a red light, and the unqualified video information is stored in the storage hard disk.

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