Airtightness detection device

Abstract

The utility model discloses an air tightness detection device, which comprises a machine body communicated with a PLC (Programmable Logic Controller), a leak detector and a workpiece temperature detection unit are arranged on the machine body, the workpiece temperature detection unit detects the temperature of a workpiece and uploads the temperature, the air tightness detection device further comprises an environment temperature detection unit and an alarm unit, and the environment temperature detection unit detects the environment temperature and uploads the environment temperature. The leak detector operates when receiving a returned starting signal, and the alarm unit gives an alarm when receiving a returned alarm signal. The airtightness detection device provided by the utility model gives an alarm when the difference between the ambient temperature and the temperature of the workpiece to be detected is large, and the leak detector works to carry out airtightness detection on the workpiece to be detected when the difference between the ambient temperature and the temperature of the workpiece to be detected is small, so that the accuracy of the detection result can be improved, and the misjudgment of qualified products can be reduced.

Description

Technical Field

[0001] This utility model relates to an airtightness testing device, specifically an airtightness testing device for inspecting the airtightness of components. Background Technology

[0002] Air tightness testing is a crucial step in ensuring product quality and safety. During manufacturing, air tightness issues can lead to leaks, affecting product performance and even posing safety hazards. A common method for air tightness testing involves filling the workpiece with gas, using minute changes in gas pressure and flow rate to assess air tightness. However, the gas temperature is affected by both product and ambient temperatures. Higher product temperatures result in higher leakage values, potentially leading to false positives for qualified products. Conversely, lower product temperatures result in lower leakage values, distorting the test data and affecting the accuracy of the air tightness test results.

[0003] Chinese patent document CN210071236U discloses an engine end cover airtightness testing device, relating to the field of automotive parts testing. The device includes a test bench with a booster pump on one side and a connecting pipe at one end of the booster pump on the same side. A control panel is mounted on the upper surface of the test bench, and a testing device is embedded in the center of the upper surface. An instrument panel is mounted on the rear upper surface of the test bench, which is fixed to the ground by fixed feet. The testing device includes a counterweight plate with a connecting rod above it and a fixed platform above it. A hydraulic rod is located below the counterweight plate. A sealing gasket is located at the edge of the fixed platform, and an air inlet is located at its center. An air inlet pipe is connected to the air inlet below the fixed platform, and a heating device is installed inside the air inlet pipe.

[0004] The existing technology includes a heating device that heats the gas in the intake manifold, simulating the actual temperature of the cylinder head during use, thus significantly enhancing the reliability of the test results. However, the need for an additional heating device increases the testing cost.

[0005] Another Chinese patent document, CN113483973A, discloses a high-precision dry-type airtightness testing device and method for engine cylinder heads. The device includes two leak testers, two sealing plates, a standard sample, a cylinder head to be tested, temperature sensors, an industrial computer, and a PLC. The two leak testers are connected to the standard sample and the cylinder head to be tested, respectively. The standard sample is a cylinder head with zero leakage. Leakage is detected using a workpiece comparison method. Temperature sensors are installed inside the two sealing plates to detect the temperatures of the standard sample and the cylinder head to be tested, and these temperatures are uploaded to the PLC. The PLC then calculates the final leakage amount of the cylinder head. Simultaneously, the device has a temperature compensation function. Temperature compensation experience data is pre-written into the PLC (Programmable Logic Controller), which can calculate the impact of temperature differences on temperature and compensate for this in the final leakage detection result.

[0006] In this existing technology, by simultaneously testing standard samples and ordinary cylinder heads under test, the influence of surrounding environmental factors on the cylinder head leakage detection results is minimized. It also features temperature compensation, ensuring accurate and stable measurement results regardless of environmental factors. However, when performing temperature compensation, a large difference between the product temperature and the ambient temperature requires a larger compensation value, leading to reduced accuracy and potential misjudgments of product conformity. Utility Model Content

[0007] To address the technical problem of misjudging product quality during airtightness testing in existing technologies when there are large temperature differences, this invention provides an airtightness testing device. The device includes a main body that communicates with a PLC. The main body is equipped with a leak detector and a workpiece temperature detection unit. The workpiece temperature detection unit detects and uploads the workpiece temperature. The device also includes an ambient temperature detection unit and an alarm unit. The ambient temperature detection unit detects and uploads the ambient temperature. The leak detector operates upon receiving a feedback start signal, and the alarm unit sounds an alarm upon receiving a feedback alarm signal. The PLC calculates the difference between the uploaded ambient temperature and the workpiece temperature, and then sends out an alarm signal when the difference is greater than 3°C and a start signal when the difference is less than 3°C.

[0008] In existing technologies, after detecting the temperature of the workpiece under test, the required temperature difference is calculated using a PCL (Programmable Gravity Increasing) and then compensated for in the final test result to improve the accuracy of the test result. However, when the temperature difference is too large, it indicates that the test result is severely affected by the ambient temperature. Even with a relatively large compensation for the final result, it is still easy to misjudge the product's conformity.

[0009] Therefore, compared with existing technologies, this solution adds an ambient temperature detection unit and an alarm unit. After the ambient temperature detection unit collects the ambient temperature, both the ambient temperature and the workpiece temperature are uploaded. The PLC, which communicates with the machine body, receives the uploaded ambient and workpiece temperatures. If the difference between the ambient and workpiece temperatures is too large, the alarm unit receives the returned alarm signal and issues an alarm. Furthermore, when the difference between the ambient and workpiece temperatures is large, even if the leak detector performs a test, the result will have a large error, which may affect the quality assessment of the workpiece and easily lead to misjudgments of product conformity. Therefore, when the difference between the ambient and workpiece temperatures is large, the leak detector will not receive the activation unit and will not operate, reducing ineffective operation and avoiding misjudgments under large temperature differences. Only when the difference between the ambient and workpiece temperatures is small will the leak detector receive the activation signal and start the test, ensuring the accuracy of the test results.

[0010] Preferably, the machine body is provided with a workpiece placement position, and a workpiece temperature detection unit is arranged on one side of the workpiece placement position. In this solution, placing the workpiece temperature detection unit on one side of the workpiece placement position can improve the accuracy of the detected workpiece temperature.

[0011] Preferably, a mounting plate is provided on one side of the workpiece placement position, and the workpiece temperature detection unit is mounted on the mounting plate. This solution utilizes the mounting plate to install the workpiece temperature detection unit on the machine body, resulting in a simple structure and reduced device cost.

[0012] Preferably, the workpiece temperature detection unit is mounted on the mounting plate in an adjustable position. Considering the differences in shape and size of different workpieces, the position of the workpiece temperature detection unit needs to be adjusted according to the actual workpiece being detected. Therefore, in this solution, the adjustable position of the workpiece temperature detection unit on the mounting plate can improve the accuracy of workpiece temperature detection and also avoid interference between the workpiece temperature detection unit and the workpiece.

[0013] Preferably, the mounting plate is equipped with an adjustable connector, and the workpiece temperature detection unit is connected to the connector. In this design, the position of the workpiece temperature detection unit is adjusted by means of an adjustable connector, resulting in a simple structure and reduced device cost.

[0014] Preferably, the mounting plate has a mounting groove, and the connector is located within the mounting groove. In this design, the connector is positioned behind the mounting groove, and its position within the groove can be adjusted according to the workpiece position, thereby adjusting the position of the workpiece temperature detection unit. This design is simple in structure and reduces the cost of the device.

[0015] Preferably, the ambient temperature detection unit is located in the middle of the machine body. In this design, placing the ambient temperature detection unit in the middle can improve the accuracy of ambient temperature detection, thereby improving the accuracy of the received signal and avoiding erroneous operation of the machine body.

[0016] Preferably, the machine body is equipped with a display unit for displaying the ambient temperature and the working temperature. In this design, the display unit facilitates the operator's viewing of the ambient temperature and the workpiece temperature, allowing for manual operation when necessary.

[0017] This utility model has the following beneficial effects:

[0018] 1. The airtightness detection device of this utility model alarms when the ambient temperature and the temperature of the workpiece to be tested differ significantly, and operates when the difference between the ambient temperature and the temperature of the workpiece to be tested is small, thereby performing airtightness testing on the workpiece to be tested, which can improve the accuracy of the test results and reduce misjudgment of qualified products.

[0019] 2. The selection of the positions of the ambient temperature detection unit and the workpiece temperature detection unit can improve the accuracy of the collected temperature, thereby improving the accuracy of the final detection results.

[0020] 3. The display unit is designed to allow operators to view the ambient temperature and workpiece temperature, enabling them to perform manual operations when necessary. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of an embodiment of an airtightness detection device according to the present invention. Detailed Implementation

[0022] The following detailed description illustrates the specific implementation method:

[0023] 1. Definition

[0024] PLC: A digital electronic system specifically designed for industrial applications. It uses a programmable memory to store instructions for performing logical operations, sequential control, timing, counting, and arithmetic operations, and controls various types of mechanical equipment or production processes through digital or analog inputs and outputs.

[0025] 2. The reference numerals in the accompanying drawings of the instruction manual include: 1. Workpiece temperature detection unit; 2. Ambient temperature detection unit; 3. Leak detector; 4. Alarm unit; 5. Display unit; 6. Workpiece placement position.

[0026] The basic implementation examples are as follows: Figure 1The diagram illustrates an airtightness detection device, comprising a body communicating with a PLC. The body is equipped with a leak detector 3 and a workpiece temperature detection unit 1. The workpiece temperature detection unit 1 detects and uploads the workpiece temperature. In this embodiment, the workpiece temperature detection unit 1 uses an infrared temperature sensor. Specifically, the lower part of the body has a workpiece placement position 6, and a mounting plate is provided on one side of the workpiece placement position 6. The mounting plate has an adjustable connector. The workpiece temperature detection unit 1 is connected to the connector, thereby allowing the position of the workpiece temperature detection unit 1 on the mounting plate to be adjustable to accommodate workpieces of different sizes and specifications. In this embodiment, the mounting plate has a mounting groove, and the connector is located within the mounting groove. The connector is a bolt, and the mounting groove can be an arc-shaped groove formed on the mounting plate. In other embodiments, other position adjustment methods can also be used, such as opening connection holes at different positions on the mounting plate. When installing the workpiece temperature detection unit 1, the appropriate connection hole on the mounting plate can be selected according to the size and specifications of the workpiece to be tested. The bolt connection method ensures the stability of the connector within the connection groove during installation of the workpiece temperature detection unit 1.

[0027] It also includes an ambient temperature detection unit 2 and an alarm unit 4, and a display unit 5 on the main body to display the ambient temperature and operating temperature. The ambient temperature detection unit 2 is located in the middle of the main body, and the display unit 5 is located at the top of the main body. The ambient temperature detection unit 2 detects the ambient temperature and uploads it. The leak detector 3 runs when it receives the returned start signal, and the alarm unit 4 sounds an alarm when it receives the returned alarm signal. The alarm unit 4 can use a voice alarm or a light alarm. If the alarm method is a voice alarm, the alarm unit 4 is a speaker; if the alarm method is a light alarm, the alarm unit 4 can be an LED light. Alternatively, the display unit 5 can be used for prompting.

[0028] The specific implementation process is as follows: The airtightness detection device in this embodiment is used in conjunction with a PLC. The PLC can calculate the difference between the uploaded ambient temperature and the workpiece temperature, and then provide an alarm signal when the difference is greater than 3°C, and a start signal when the difference is less than 3°C. The 3°C setting is determined by the operator based on the actual situation. The above process utilizes calculation and comparison functions, which are all available in existing PLC technologies and can be skillfully applied.

[0029] In use, after placing the workpiece to be tested in workpiece placement position 6, the workpiece temperature detection unit 1 collects the surface temperature of the workpiece, and the ambient temperature detection unit 2 detects the ambient temperature. The collected workpiece and ambient temperatures are then uploaded to the PLC for processing and feedback of corresponding signals. Upon receiving an alarm signal, the alarm unit 4 issues an alarm notification. Upon receiving a start signal, the leak detector 3 operates to perform an airtightness test on the workpiece, and the test results are also uploaded to the PLC for processing.

[0030] The above descriptions are merely embodiments of this utility model. Commonly known structures and characteristics are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are knowledgeable of all existing technologies in that field, and possess the ability to apply conventional experimental methods prior to that date. Therefore, those skilled in the art can, based on the guidance provided in this application, improve and implement this solution in conjunction with their own capabilities. Typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of this utility model. These modifications and improvements should also be considered within the scope of protection of this utility model, and will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. An airtightness detection device, comprising a body communicating with a PLC, wherein a leak detector and a workpiece temperature detection unit are mounted on the body, the workpiece temperature detection unit detecting the workpiece temperature and uploading the data, characterized in that: It also includes an ambient temperature detection unit and an alarm unit. The ambient temperature detection unit detects and uploads the ambient temperature. The leak detector runs when it receives a back start signal. The alarm unit sounds an alarm when it receives a back alarm signal. The PLC calculates the difference between the uploaded ambient temperature and the workpiece temperature, and then sends out an alarm signal when the difference is greater than 3°C and a start signal when the difference is less than 3°C.

2. The airtightness detection device according to claim 1, characterized in that: The machine body is provided with a workpiece placement position, and a workpiece temperature detection unit is provided on one side of the workpiece placement position.

3. The airtightness detection device according to claim 2, characterized in that: A mounting plate is provided on one side of the workpiece placement position, and the workpiece temperature detection unit is mounted on the mounting plate.

4. The airtightness detection device according to claim 3, characterized in that: The workpiece temperature detection unit is adjustable and mounted on the mounting plate.

5. The airtightness detection device according to claim 4, characterized in that: The mounting plate is equipped with a position-adjustable connector, and the workpiece temperature detection unit is connected to the connector.

6. The airtightness detection device according to claim 5, characterized in that: The mounting plate is provided with a mounting groove, and the connector is located in the mounting groove.

7. The airtightness detection device according to claim 6, characterized in that: The ambient temperature detection unit is located in the middle of the machine body.

8. The airtightness detection device according to any one of claims 1-7, characterized in that: The machine body is equipped with a display unit that displays the ambient temperature and the operating temperature.

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