Air tightness testing equipment

Abstract

The utility model aims to provide the air tightness test equipment which is high in integration level, small in interference, good in compatibility and capable of rapidly detecting the sealing performance of the sealing element. The testing device comprises an air source, a pressure reducing valve, an inflation valve, an exhaust valve, a testing valve, an equivalent cavity and a to-be-tested product, the air source is connected into the inflation valve through the pressure reducing valve, the inflation valve and the exhaust valve are both connected into one end of the testing valve, the other end of the testing valve is connected into the equivalent cavity, the to-be-tested product is connected into the equivalent cavity, and the to-be-tested product is connected into the equivalent cavity. A direct pressure sensor is connected among the inflation valve, the exhaust valve and the test valve, and a differential pressure sensor is connected between the equivalent cavity and the to-be-tested product. The air tightness tester is applied to the technical field of air tightness testers.

Description

Technical Field

[0001] The utility model is applied to the technical field of air tightness testers, and particularly relates to air tightness test equipment. Background Art

[0002] Air tightness detector, also known as leakage tester. Air tightness detection is an important means to measure the sealing performance of many industrial products. For example, in many industries such as automobiles, air conditioners, refrigerators, gas appliances, speakers, speakers and medical devices, it is necessary to conduct air tightness (or sealing) detection on the sealing parts of related products. The test results are one of the key indicators to measure product quality. Especially in audio, new energy, aerospace and other industries, air tightness detection is an important and frequently used method. At present, domestic enterprises generally use the bubble method or pressure change method to judge the waterproof detection index of products. During the detection process, all workpieces are placed in a water tank or a pressure gauge is used. The air tightness is judged by the number of bubbles and the change of the pressure gauge value. This method is relatively backward, the detection method and equipment are simple, and the results are intuitive, but the detection accuracy and efficiency are low, and the human factors have a greater impact. It can even only be visually observed and cannot be quantitatively expressed, which directly affects the quality and performance of the product. In the past, the commonly used air tightness tester is usually a single channel and direct positive pressure or negative pressure test. Therefore, it is necessary to provide an air tightness test equipment with high integration, less interference, good compatibility, and the ability to quickly detect the sealing performance of the seal. Utility Model Content

[0003] The technical problem to be solved by the utility model is to overcome the deficiencies of the prior art and provide an airtightness testing device with high integration, less interference, good compatibility and the ability to quickly detect the sealing performance of a sealing member.

[0004] The technical solution adopted by the utility model is: the utility model includes an air source, a pressure reducing valve, an air charging valve, an exhaust valve, a test valve, an equivalent cavity and a product to be tested, the air source is connected to the air charging valve through the pressure reducing valve, the air charging valve and the exhaust valve are both connected to one end of the test valve, the other end of the test valve is connected to the equivalent cavity and the product to be tested, a direct pressure sensor is connected between the air charging valve, the exhaust valve and the test valve, and a differential pressure sensor is connected between the equivalent cavity and the product to be tested.

[0005] It can be seen from the above scheme that the present application adopts a combination of a miniature differential pressure sensor, a direct pressure sensor and a control valve. Compared with other methods that use a differential pressure transmitter plus a sealing valve, it has a smaller size and higher integration, a more centralized air path, higher air pressure accuracy, better anti-interference, and is compatible with positive and negative pressure tests. It can be applied in more scenarios. In order to make the airtight test more stable and reliable, it is necessary to reduce the overall test air path, integrate the differential pressure sensor and the direct pressure sensor into the control valve, and set the corresponding air pressure by adjusting the electrical proportional valve. The direct pressure sensor is then fed back to the main control board to obtain a more accurate test air pressure, and the valve body inflation, pressure stabilization, and exhaust process are controlled to detect the sealing performance of the seal.

[0006] A preferred solution is that the air tightness testing equipment performs inflation, pressure maintenance, testing, and exhaust in sequence, reads the direct pressure value of the direct pressure sensor during the pressure maintenance process, and reads the differential pressure value of the differential pressure sensor during the test process.

[0007] A preferred solution is that the differential pressure sensor is connected to a digital display, and when the product to be tested has no leakage, the reading of the digital display approaches zero; when the product to be tested has leakage, the reading of the digital display increases as the leakage increases. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is the structural principle diagram of the utility model;

[0009] Figure 2 It is a pressure value variation diagram of the utility model;

[0010] Figure 3 is a graph showing changes in the readings of the differential pressure sensor when the product to be tested has no leakage;

[0011] Figure 4 is a graph showing changes in the readings of the differential pressure sensor when the product to be tested leaks;

[0012] Figure 5 It is a test flow chart of the utility model. DETAILED DESCRIPTION

[0013] like Figures 1 to 3 As shown, in this embodiment, the utility model 1 includes an air source 1, a pressure reducing valve 2, an air charging valve 3, an exhaust valve 4, a test valve 5, an equivalent cavity 6 and a product to be tested 7. The air source 1 is connected to the air charging valve 3 via the pressure reducing valve 2. The air charging valve 3 and the exhaust valve 4 are both connected to one end of the test valve 5. The other end of the test valve 5 is connected to the equivalent cavity 6 and the product to be tested 7. A direct pressure sensor 8 is connected between the air charging valve 3, the exhaust valve 4 and the test valve 5. A differential pressure sensor 9 is connected between the equivalent cavity 6 and the product to be tested 7.

[0014] The upper computer controls the instrument through TCP / IP or USART communication. First, the required test pressure is set. After the test pressure is set, the valve body is controlled to open the inflation valve to inflate the product to be tested. During the inflation process, the direct pressure sensor 8 is read to obtain the pressure of the test pressure, thereby adjusting the test pressure. After inflation, the inflation valve is closed and the balance valve is opened to stabilize the air pressure in the cavity. Then the differential pressure sensor 9 is read to obtain the pressure difference between the test piece and the standard piece, thereby judging the quality of the test piece. The standard piece refers to the equivalent cavity 6, and the test piece refers to the test piece 7. Figure 5 As shown, the test valve 5 includes a differential pressure valve and a balancing valve.

[0015] Highly integrated control valves have lower requirements for air circuits and less interference. This tester can be used to detect the sealing performance of seals more quickly and conveniently. By adjusting the test air pressure to adapt to different levels of waterproof tests, you can choose to use positive pressure testing or negative pressure (vacuum) testing according to different application scenarios.

[0016] like Figures 1 to 5 As shown, in this embodiment, the air tightness testing equipment performs inflation, pressure maintenance, testing, and exhaust in sequence, and reads the direct pressure value of the direct pressure sensor 8 during the pressure maintenance process, and reads the differential pressure value of the differential pressure sensor 9 during the test process.

[0017] like Figure 3 to Figure 4 As shown, in this embodiment, the differential pressure sensor 9 is connected to a digital display 10. When the test product 7 has no leakage, the reading of the digital display 10 approaches zero; when the test product 7 has a leakage, the reading of the digital display 10 increases as the leakage increases.

Claims

1. An airtightness testing device, characterized in that: It comprises an air source (1), a pressure reducing valve (2), an air charging valve (3), an air exhaust valve (4), a test valve (5), an equivalent cavity (6) and a test object (7), wherein the air source (1) is connected to the air charging valve (3) via the pressure reducing valve (2), the air charging valve (3) and the air exhaust valve (4) are both connected to one end of the test valve (5), and the other end of the test valve (5) is connected to the equivalent cavity (6) and the test object (7), a direct pressure sensor (8) is connected between the air charging valve (3), the air exhaust valve (4) and the test valve (5), and a differential pressure sensor (9) is connected between the equivalent cavity (6) and the test object (7).

2. The airtightness testing device according to claim 1, characterized in that: The air tightness testing equipment performs inflation, pressure maintenance, testing, and exhaust in sequence, and reads the direct pressure value of the direct pressure sensor (8) during the pressure maintenance process, and reads the differential pressure value of the differential pressure sensor (9) during the testing process.

3. The airtightness testing device according to claim 1, characterized in that: The differential pressure sensor (9) is connected to a digital display (10); when the test object (7) has no leakage, the reading of the digital display (10) approaches zero; when the test object (7) has leakage, the reading of the digital display (10) increases as the leakage increases.

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