Air tightness detection jig

Abstract

The utility model discloses an air tightness detection jig, which relates to the field of controllers and comprises a control panel, a flow meter, a one-way electromagnetic valve and a pressure gauge. The air inlet end of the flowmeter is connected with an air source through the control valve, the air outlet end of the flowmeter is connected with the air inlet end of the one-way electromagnetic valve, and the air outlet end of the one-way electromagnetic valve, the detected equipment and the detection end of the pressure gauge are jointly connected to the three-end air vent; the electrical ends of the flowmeter, the one-way electromagnetic valve and the pressure gauge are connected to a control panel, and the control panel conducts flow control, switch control and pressure detection on the flowmeter, the one-way electromagnetic valve and the pressure gauge. According to the scheme, the flow meter, the one-way electromagnetic valve and the pressure gauge are detected by using a control panel, and the pressure gauge measures the detection process of the detected equipment in real time by using a three-way port. Various detected conditions can be displayed through the cooperation of the buzzer circuit and the light prompt circuit, the single-chip microcomputer is adopted for control, various indexes of detected air pressure can be changed according to different detected devices, and the compatibility is higher.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of air tightness testing, and in particular to an air tightness testing jig. Background Art

[0002] With the continuous development of the industrial field, the requirements for product safety performance are getting higher and higher. Air tightness testing can timely discover potential problems in products and prevent safety accidents caused by gas leakage. For example, in the new energy industry, if the air tightness is not good, water will enter the battery and the battery will short-circuit; in the automobile braking system, if the air tightness is not good, it may cause brake failure and cause traffic accidents. Therefore, air tightness testing is an important means to prevent safety accidents.

[0003] At present, the airtightness test fixtures or equipment have problems such as complex structure, cumbersome testing process and low efficiency. How to set up a simple, efficient and universal airtightness test fixture is a technical problem that needs to be solved urgently. Utility Model Content

[0004] The embodiment of the present application provides an air tightness detection fixture to solve the problems of complex structure, cumbersome detection process and low efficiency. The air tightness detection fixture includes a control board, a flow meter, a one-way solenoid valve and a pressure gauge; the air inlet end of the flow meter is connected to the air source through the control valve, the air outlet end of the flow meter is connected to the air inlet end of the one-way solenoid valve, and the air outlet end of the one-way solenoid valve, the device under test and the detection end of the pressure gauge are connected to the three terminals of the three-terminal vent;

[0005] The electrical ends of the flow meter, the one-way solenoid valve and the pressure gauge are connected to the control board, and the control board performs flow control, switch control and pressure detection on the flow meter, the one-way solenoid valve and the pressure gauge respectively.

[0006] Specifically, the control board includes an MCU chip, an RS485 communication module, and a light prompt circuit;

[0007] The electrical ends of the flow meter, one-way solenoid valve and pressure gauge are connected to the RS485 communication module to send control instructions and collect signals. The RS485 communication module and the light prompt circuit are connected to the MCU chip; the light prompt circuit includes NG light, green light and yellow light. The NG light indicates that the airtight test status is unqualified, the green light indicates that the airtight test is qualified, and the yellow light indicates that the airtight test is in progress.

[0008] Specifically, the control board is also provided with a buzzer circuit for providing alarm prompts in different states.

[0009] Specifically, the MCU chip is an STM32F103C8T6 chip. The PB1 pin of the MCU chip is led out as the RS485-DR communication terminal of the RS485 communication module, and the PA1 and PA2 pins are respectively led out as the RE terminal and TX terminal for interacting with the RS485 communication module.

[0010] Specifically, the RS485 communication module includes an ISO3082 chip. The RE pin and DE pin of the ISO3082 chip are jointly used as the RS485-DR communication terminal. The R pin and D pin are respectively led out as the RX terminal and TX terminal and connected to the MCU chip;

[0011] A jumper resistor R24 is provided on the A pin and B pin of the ISO3082 chip, and the A pin and B pin are respectively led out as the RS485_A and RS485_B terminals and connected to the electrical terminals of the flow meter, one-way solenoid valve, and pressure gauge.

[0012] Specifically, the light prompt circuit includes a first plug connector. The first port of the introduction end of the first plug connector accesses the 3.3V power supply, the second port is grounded, the third port is the DIO port and is connected to the PB4 pin of the MCU chip, the fourth port is the CLK port and is connected to the PA15 pin of the MCU chip, and the fifth port is the STB port and is connected to the PB3 pin of the MCU chip; the third port of the lead-out end of the first plug connector is connected to the yellow LED, the fourth port is connected to the green LED, and the negative electrodes of the yellow LED and the green LED are jointly grounded.

[0013] Specifically, the light prompt circuit includes a second plug connector. The first port of the introduction end of the second plug connector accesses the 5V voltage, the second port is grounded, the third port is the TX1 port and is connected to the PB6 pin of the MCU chip, and the fourth port is the RX1 port and is connected to the PB7 pin of the MCU chip;

[0014] The third port of the lead-out end of the second plug connector is connected to the LED1, the fifth port of the lead-out end of the first plug connector is connected to the LED2, and the LED1 and LED2 are connected in common cathode and grounded to form an NG lamp.

[0015] Specifically, the buzzer circuit includes a 5V voltage input terminal. The voltage input terminal is connected to one end of the buzzer through a pull-up resistor R28. The other end of the buzzer is connected to the collector of the triode Q2. A resistor R35 is connected between the base and emitter of Q2 and the emitter is grounded. The PA8 pin of the MCU chip is led out as the BUZ terminal and connected to the buzzer circuit and connected to the base of Q2 through a resistor R133.

[0016] Specifically, a voltage stabilizing diode ZD1 is connected between the PF6 pin and PF7 pin of the MCU chip, and a first capacitor C12 and a second capacitor C14 are connected in parallel at both ends of the diode.

[0017] Specifically, the negative electrode of the zener diode is connected to the 3.3V power supply voltage, and the positive electrode is grounded.

[0018] The beneficial effects brought by the technical solution provided by the embodiments of the present application at least include: The airtightness detection fixture of the present application can greatly simplify the overall structure, use a control board to detect the flow meter, one-way solenoid valve and pressure gauge, and the pressure gauge can use a three-way port to measure the detection process of the device under test in real time. For various detection situations, it can be indicated by the cooperation display of the buzzer circuit and the light prompt circuit, and this solution is controlled by a single-chip microcomputer, and can change the various indicators of the detection air pressure according to different devices under test, with stronger compatibility. Description of the Drawings

[0019] Figure 1 is the structural schematic diagram of the airtightness detection fixture provided by the embodiments of the present application;

[0020] Figure 2 is the circuit diagram of the airtightness detection fixture;

[0021] Figure 3 is the circuit schematic diagram of the MCU chip;

[0022] Figure 4 is the detailed circuit diagram of the RS485 communication module;

[0023] Figure 5 is the circuit schematic diagram of the light prompt circuit;

[0024] Figure 6 is the structural schematic diagram of the buzzer circuit. Detailed Embodiments

[0025] To make the objectives, technical solutions, and advantages of the present application clearer, the following will further describe the embodiments of the present application in detail with reference to the drawings.

[0026] As used herein, "a plurality" means two or more. "And / or" describes the association relationship of associated objects and indicates that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally represents an "or" relationship between the associated objects before and after.

[0027] Figure 1It is a structural schematic diagram of the airtightness detection fixture provided by the embodiment of the present application. The fixture includes a control board, a flow meter, a one-way solenoid valve, and a pressure gauge. The electrical terminals of the flow meter, the one-way solenoid valve, and the pressure gauge are connected to the control board. The control board respectively performs flow control, switch control, and pressure detection on the flow meter, the one-way solenoid valve, and the pressure gauge. Among them, the air inlet end of the flow meter is connected to the air source through a control valve. The air outlet end of the flow meter is connected to the air inlet end of the one-way solenoid valve. The air outlet end of the one-way solenoid valve, the device under test, and the detection end of the pressure gauge are commonly connected to the three terminals of the three-way air vent. An electric valve or a manual valve can be set between the flow meter and the air source in this solution, mainly controlling the on / off of the air source.

[0028] Figure 2 It is the circuit diagram of the airtightness detection fixture. The control board in this solution includes an MCU chip, an RS485 communication module, and a lighting prompt circuit. The electrical terminals of the flow meter, the one-way solenoid valve, and the pressure gauge are connected to the RS485 communication module U4. The RS485 communication module and the lighting prompt circuit are connected to the MCU chip, and the control instructions and collected signals are sent according to the MCU chip. To simplify the device, the present application uses sound and light prompts to represent various states. The lighting prompt circuit includes an NG lamp, a green lamp, and a yellow lamp. The NG lamp indicates that the effect of the airtightness test state is unqualified. The green lamp indicates that the airtightness test is qualified. The yellow lamp indicates that the airtightness detection is in progress. A buzzer circuit is also provided on the control board for alarm prompts in different states.

[0029] Figure 3 It is the circuit schematic diagram of the MCU chip. The MCU chip is an STM32F103C8T6 chip. The PB1 pin of the MCU chip is led out as the RS485-DR communication end of the RS485 communication module. The PA1 and PA2 pins are respectively led out to interact with the RE end and the TX end of the RS485 communication module. A voltage stabilizing diode ZD1 is connected between the PF6 and PF7 pins of the MCU chip, and a first capacitor C12 and a second capacitor C14 are connected in parallel at both ends of the diode. The negative pole of the voltage stabilizing diode is connected to the 3.3V power supply voltage, and the positive pole is grounded. The introduction of the voltage stabilizing diode ZD1 and the capacitor can stabilize the voltage of the MCU and improve the stability.

[0030] Figure 4It is the detailed circuit diagram of the RS485 communication module. The ISO3082 chip is selected as the main control for the RS485 communication module. The RE pin and DE pin of the ISO3082 chip together serve as the RS485-DR communication terminal. The R pin and D pin are respectively led out as the RX terminal and TX terminal, and are connected to the MCU chip. For the acquisition side, a jumper resistor R24 is set on the A pin and B pin of the ISO3082 chip, and the A pin and B pin are respectively led out as the RS485_A and RS485_B terminals as general data communication terminals, and are connected to the electrical terminals of the flowmeter, one-way solenoid valve, and pressure gauge through these two terminals.

[0031] Figure 5 It is the circuit schematic diagram of the light prompt circuit. This circuit requires two PIN plug connectors to connect to the external circuit, including the first plug connector and the second plug connector. The first port of the introduction end of the first plug connector CN5 (the side connected to the MCU chip) accesses the 3.3V power supply, the second port is grounded, the third port is the DIO port, connected to the PB4 pin of the MCU chip, the fourth port is the CLK port, connected to the PA15 pin of the MCU chip, and the fifth port is the STB port, connected to the PB3 pin of the MCU chip; the third port of the lead-out end of the first plug connector (the side connected to the external circuit) is connected to the yellow LED, the fourth port is connected to the green LED, and the negative electrodes of the yellow LED and the green LED are commonly grounded.

[0032] The first port of the introduction end of the second plug connector accesses the 5V voltage, the second port is grounded, the third port is the TX1 port, connected to the PB6 pin of the MCU chip, the fourth port is the RX1 port, connected to the PB7 pin of the MCU chip; the third port of the lead-out end of the second plug connector is connected to LED1, the fifth port of the lead-out end of the first plug connector is connected to LED2, and LED1 and LED2 are connected in common cathode and grounded to form the NG lamp.

[0033] Figure 6 It is the structural schematic diagram of the buzzer circuit, including a 5V voltage input terminal. The voltage input terminal is connected to one end of the buzzer through a pull-up resistor R28. The other end of the buzzer is connected to the collector of the triode Q2. A resistor R35 is connected between the base and emitter of Q2 and the emitter is grounded. The PA8 pin of the MCU chip leads out the BUZ terminal and is connected to the buzzer circuit, and is connected to the base of Q2 through the resistor R133.

[0034] The specific working steps of this circuit are as follows: Turn on the power switch of the control board and the manual valve, adjust the flowmeter, and adjust the appropriate flow value according to the volume of the device to be measured. For example, the set flow value this time is 15Kpa. When the flowmeter detects the inflow of air pressure, the one-way electromagnetic valve automatically opens. After the air pressure stabilizes, the output port is connected to the device to be measured and inflation starts.

[0035] During the inflation process, the control board reads the pressure value returned by the pressure gauge every 100 ms. When the read pressure value is greater than 15 Kpa, the one-way solenoid valve is closed. When the air pressure input to the device under test is stable for one minute, the yellow light of the fixture flashes at a frequency of 1 Hz; when the value read from the pressure gauge is greater than or equal to 14.8 Kpa, the fixture enters the detection mode; when the value read from the pressure gauge is less than 14.8 Kpa, the fixture exits the detection mode, and at this time the NG light is on, indicating that the airtightness test of the product is unqualified. In the test mode, the control board reads the pressure value once every 100 ms. After the test light yellow light flashes at a frequency of 2 Hz for one minute, when the leaked air pressure of the device under test ≤ 0.1 Kpa, it means the test passes, and at this time the buzzer sounds briefly and the test green light remains on; when the leaked air pressure > 0.1 Kpa, it means the test fails, the buzzer sounds continuously, and the test light red light remains on.

[0036] In summary, the airtightness detection fixture of the present application can greatly simplify the overall structure. A single control board is used to detect the flow meter, one-way solenoid valve and pressure gauge. The pressure gauge can use a three-way port to measure the detection process of the device under test in real time. For various detection situations, the cooperation display of the buzzer circuit and the light prompt circuit can be used to indicate. Moreover, this solution is controlled by a single-chip microcomputer and can change the various indicators of the detection air pressure according to different devices under test, with stronger compatibility.

[0037] The preferred embodiments of the present invention have been described above; it should be understood that the present invention is not limited to the above specific implementation manners. The devices and structures not described in detail should be understood to be implemented in a common manner in the art; any person skilled in the art can make many possible changes and modifications without departing from the technical solution of the present invention, or modify it into an equivalent embodiment with equivalent changes, which does not affect the essence of the present invention; therefore, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. An airtightness detection fixture, characterized in that: It includes a control panel, a flow meter, a one-way solenoid valve and a pressure gauge; the air inlet end of the flow meter is connected to the air source through the control valve, the air outlet end of the flow meter is connected to the air inlet end of the one-way solenoid valve, and the air outlet end of the one-way solenoid valve, the device under test and the detection end of the pressure gauge are connected to the three terminals of the three-terminal vent; The electrical ends of the flow meter, the one-way solenoid valve and the pressure gauge are connected to the control board, and the control board performs flow control, switch control and pressure detection on the flow meter, the one-way solenoid valve and the pressure gauge respectively.

2. The airtightness detection jig according to claim 1, characterized in that: The control board includes an MCU chip, an RS485 communication module, and a light prompt circuit; The electrical ends of the flow meter, one-way solenoid valve and pressure gauge are connected to the RS485 communication module to send control instructions and collect signals. The RS485 communication module and the light prompt circuit are connected to the MCU chip; the light prompt circuit includes NG light, green light and yellow light. The NG light indicates that the airtight test status is unqualified, the green light indicates that the airtight test is qualified, and the yellow light indicates that the airtight test is in progress.

3. The airtightness detection jig according to claim 2, characterized in that: The control board is also provided with a buzzer circuit for providing alarm prompts in different states.

4. The airtightness detection jig according to claim 3, characterized in that: The MCU chip is an STM32F103C8T6 chip, the PB1 pin of the MCU chip is led to the RS485-DR communication end of the RS485 communication module, and the PA1 and PA2 pins are respectively led to the RE end and TX end for interacting with the RS485 communication module.

5. The airtightness detection jig according to claim 4, characterized in that: The RS485 communication module includes an ISO3082 chip, the RE pin and the DE pin of the ISO3082 chip are used as RS485-DR communication terminals, the R pin and the D pin are respectively led out as the RX terminal and the TX terminal, and are connected to the MCU chip; A jumper resistor R24 ​​is provided on the A pin and the B pin of the ISO3082 chip, and the A pin and the B pin lead out the RS485_A and RS485_B terminals respectively, which are connected to the electrical ends of the flow meter, the one-way solenoid valve and the pressure gauge.

6. The airtightness detection jig according to claim 2, characterized in that: The light prompt circuit includes a first plug connector, the first port of the first plug connector input end is connected to a 3.3V power supply, the second port is grounded, the third port is a DIO port connected to the PB4 pin of the MCU chip, the fourth port is a CLK port connected to the PA15 pin of the MCU chip, and the fifth port is a STB port connected to the PB3 pin of the MCU chip; the third port of the first plug connector output end is connected to a yellow light LED, the fourth port is connected to a green light LED, and the negative poles of the yellow light LED and the green light LED are grounded together.

7. The airtightness detection jig according to claim 6, characterized in that: The light prompt circuit includes a second plug connector, wherein the first port of the second plug connector input end is connected to a 5V voltage, the second port is grounded, the third port is a TX1 port connected to a PB6 pin of the MCU chip, and the fourth port is a RX1 port connected to a PB7 pin of the MCU chip; The third port of the second plug connector lead-out end is connected to LED1, the fifth port of the first plug connector lead-out end is connected to LED2, LED1 and LED2 are connected in common cathode and grounded to form an NG lamp.

8. The airtightness detection jig according to claim 3, characterized in that: The buzzer circuit includes a 5V voltage input terminal, which is connected to one end of the buzzer through a pull-up resistor R28, and the other end of the buzzer is connected to the collector of the transistor Q2. A resistor R35 is connected between the base and emitter of Q2 and the emitter base is grounded. The PA8 pin of the MCU chip leads to a BUZ terminal connected to the buzzer circuit and is connected to the base of Q2 through a resistor R133.

9. The airtightness detection jig according to claim 4, characterized in that: A voltage stabilizing diode ZD1 is connected between the PF6 pin and the PF7 pin of the MCU chip, and a first capacitor C12 and a second capacitor C14 are connected in parallel at both ends of the diode.

10. The airtightness detection jig according to claim 9, characterized in that: The cathode of the voltage zener diode is connected to the 3.3V power supply voltage and the anode is grounded.

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