JP2007010350A - Gastight leakage inspection device and gastight leakage inspection method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gastight leakage inspection device and a gastight leakage inspection method for easily performing fine adjustment on necessary time owing to a change in an inspection environment in respective processes constituting gastight leakage inspection. <P>SOLUTION: This gastight leakage inspection device 1 is structured so as to be equipped with operation units 21 to 32 for carrying out the respective processes constituting the gastight leakage inspection and a control unit 40 for controlling the operations of the operation units 21 to 32. The control unit 40 is equipped with basic time clocking parts Tr1 to Tr8 for severally clocking basic necessary time determined for each of the respective processes, a variable quantity setting part TrK for setting variable quantities by which additional necessary time is lengthened/shortened for extendingly carrying out the respective processes after the basic operation time, and additional time clocking parts Cn1 to Cn8 for severally clocking necessary time defined as the product of the variable quantity and an adjustment factor for each of the respective operation units 21 to 32 after the end of the basic necessary time. While the basic time clocking parts and the additional time clocking parts clock the necessary time for each of the processes, the control unit 40 causes the corresponding operation units 21 to 32 to operate. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an apparatus and a method for performing an airtight leak inspection of an inspection object in a vacuum using a leakage inspection medium (tracer gas) such as helium (He) gas.

As a conventional technique, a helium leak detector (helium leak detector) that detects the amount of tracer gas leaking from an inspection object is used as an inspection method for minute airtight leakage of an inspection object that requires airtightness, such as a heat exchanger. There is an inspection method using a vacuum helium leak inspection method.
The vacuum type helium leak inspection method uses a vacuum pump or the like to evacuate the inside of an inspection chamber containing an inspection target, and then helium, which is a tracer gas, is sealed in the inspection target and leaks from the inspection target. Is introduced into a detector (helium leak detector) and the amount of leaked helium is detected using helium mass spectrometry.
FIG. 5 shows a schematic configuration of a conventional airtight leak inspection apparatus that performs a vacuum helium leak inspection.

  The hermetic leak inspection apparatus 1 includes an inspection chamber 10 for storing an inspection object (workpiece) 90, a chamber exhaust pump 21 for evacuating the inspection chamber 10, and vacuum exhausting the inspection chamber 10 by the chamber exhaust pump 21. A first valve 22 that is permitted / prohibited, a work exhaust pump 23 that evacuates the work 90, and a second valve 24 that permits / prohibits evacuation of the work 90 by the work exhaust pump 22 are provided.

  Further, the airtight leakage inspection apparatus 1 includes a mixing tank 25 for mixing He gas, which is a tracer gas, with another gas (for example, nitrogen gas) to generate an inspection gas having a desired He concentration, and a mixing tank 25. A third valve 26 for permitting / prohibiting sealing of the inspection gas to the workpiece 90, a He tank 27 for storing He gas, and a second valve for permitting / prohibiting the inflow of He gas from the He tank 27 to the mixing tank 25. 4-valve 28, nitrogen tank 29 for storing nitrogen gas for diluting the inspection gas sealed in workpiece 90 to a desired He concentration, and permitting / prohibiting inflow of nitrogen gas from nitrogen tank 29 to mixing tank 25 And a fifth valve 30.

Further, the airtight leak inspection apparatus 1 opens and closes a He detector 31 that detects a test gas leaking from the workpiece 90 into the chamber 10 and a communication path for introducing He gas from the chamber 10 to the He detector 31. The 6th valve 32 for doing is provided.
Furthermore, the airtight leak inspection apparatus 1 is referred to as a vacuum exhaust process in the chamber 10, a vacuum exhaust process of the work 90, a He gas and nitrogen gas mixing process, a test gas filling process into the work 90, and a leak He gas detection process. A control unit 40 is provided for controlling the operation of these operation units 21 to 32 for executing each process.

  The hermetic leak inspection apparatus 1 executes a process for handling a gas, such as evacuation of the chamber 10 and the workpiece 90 and enclosure of high-pressure gas. For this reason, in order to perform inspection with high accuracy, it is necessary to stabilize the pressure at the time of exhaust or sealing. Therefore, as shown in FIG. 5, the control unit 40 is provided with many manual setting timers (Ts1 to Ts8), and performs time control of the operation of each operation unit 21 to 32 according to the operation time set in these setting timers. It was.

FIG. 6 is a time setting table showing setting examples of the setting timers Ts1 to Ts8 used by the control unit 40 to control the operations of the operation units 21 to 32. FIG. 7 shows the setting timers Ts1 to Ts8. It is an operation | movement time chart of the operation units 21-32 to be controlled.
The setting timer Ts1 is a timer for setting a required time from the start of the inspection to the end of the vacuum evacuation process in the inspection chamber 10. During the time set by the setting timer Ts1 from the start of the inspection, the control unit 40 The exhaust pump 21 is operated to open the first valve 22 to evacuate the inspection chamber 10, and after the time Ts1 has elapsed, the chamber exhaust pump 21 is stopped or the first valve 22 is closed. By doing so, the vacuum exhaust in the inspection chamber 10 is stopped.

  The setting timer Ts2 is a timer for setting a required time from the start of the inspection to the end of the vacuum exhausting process in the workpiece 90. During the time set by the setting timer Ts2 from the start of the inspection, the control unit 40 The pump 23 is operated to open the second valve 24 to evacuate the work 90, and after the time Ts2 has elapsed, the work exhaust pump 23 is stopped or the second valve 24 is closed. As a result, the vacuum exhaust in the workpiece 90 is stopped.

The setting timers Ts3 to Ts6 are timers for controlling the time required for the inspection gas mixing process. This process is performed in parallel while the vacuum exhaust process in the workpiece 90 is performed, and the He gas in the He tank 27 and the nitrogen gas in the nitrogen tank 29 are introduced and mixed into the mixing tank 25, respectively. And make inspection gas.
The setting timer Ts3 is a timer for setting a waiting time from the start of inspection until He gas is introduced into the mixing tank 25. The setting timer Ts4 starts counting from the end of the timing of the setting timer Ts3. 25 is a timer for setting the time from the start to the end of the introduction of He gas into the interior. The control unit 40 opens the fourth valve 28 only while the setting timer Ts4 is measuring, permits introduction of He gas into the mixing tank 25, and closes the fourth valve 28 after the setting timer Ts4 has finished counting. Thus, the introduction of He gas is prohibited.

  The setting timer Ts5 is a timer for setting a waiting time from the end of the timer Ts4 to the introduction of nitrogen gas into the mixing tank 25, and the setting timer Ts6 starts counting from the end of the setting timer Ts5. This is a timer for setting the time from the start to the end of the introduction of nitrogen gas into the mixing tank 25. The control unit 40 opens the fifth valve 30 only while the set timer Ts6 is counting, permits introduction of nitrogen gas into the mixing tank 25, and closes the fifth valve 30 after the timing of the setting timer Ts6 is completed. Therefore, the introduction of nitrogen gas is prohibited.

The setting timer Ts7 starts sealing the inspection gas produced in the mixing tank 25 into the work 90 after the introduction of the nitrogen gas into the mixing tank 25 is completed (that is, the timer Ts6 is timed), and then ends the sealing. It is a timer that sets the required time until. The setting timer Ts7 starts timing after the timer Ts6 finishes counting, and the control unit 40 opens the third valve 26 only during the timing of the setting timer Ts7, and permits the inspection gas to be enclosed in the workpiece 90. Then, after the set timer Ts7 finishes counting, the third valve 26 is closed to prevent the inspection gas from being sealed.
It is necessary to seal the inspection gas into the workpiece 90 after the exhaust of the workpiece 90 is completed. For this reason, the timer Ts2 that controls the work exhaust process so that the time measurement end time of the timer Ts2 that controls the exhaust time of the work 90 matches the time measurement start time of the set timer Ts7, that is, the time measurement end time of the timer Ts6, Timers Ts <b> 3 to Ts <b> 6 that perform a test gas mixing process that is executed in parallel with the exhaust process are adjusted.

The setting timer Ts8 introduces the inspection gas leaking from the workpiece 90 into the He detector 31 and starts the He concentration inspection after the sealing of the inspection gas into the workpiece 90 is completed (that is, the timer Ts7 finishes timing). To a time required to complete the He concentration test. The setting timer Ts8 starts timing after the timing of the timer Ts7 ends, and the control unit 40 opens the sixth valve 32 only during the timing of the setting timer Ts8 and introduces the inspection gas into the He detector 31. And the sixth valve 32 is closed after the set timer Ts8 finishes counting, and the introduction of the inspection gas is prohibited.
The He concentration test needs to be performed after the exhaust of the chamber 10 is completed. For this reason, the timer Ts1 that controls the chamber exhaust process and the exhaustion time of the timer Ts1 that controls the exhaust time of the chamber become the time measurement start time of the set timer Ts8, that is, the time measurement end time of the timer Ts7. Ts3 to Ts7 for controlling the inspection gas mixing step and the sealing step executed in parallel with the step are adjusted.

JP 2001-85833 A JP2002-14673

Each operation time set in the setting timers Ts1 to Ts8 for controlling the operation time of each of the operation units 21 to 32 described above is set by the user who performs the leak inspection according to each product as shown in the table of FIG. Each timer was set manually according to the table. However, the inspection environment (leakage amount, temperature, humidity, and moisture brought into the workpiece) is not always constant when performing a leak inspection, so the timer setting value must be finely adjusted according to the inspection environment. There is.
An example of time setting with such fine adjustment is shown in the second column of the table of FIG. 8, and an example of an operation time chart of the operation units 21 to 32 at this time is shown in FIG. 9B.

For example, in the inspection after inspecting the workpiece 90 having a large amount of leakage, it is necessary to extend the exhaust time of the chamber 10 from a normal setting. Here, as described above, since the He concentration inspection process needs to be performed after the chamber exhaust process, it is necessary to delay the He concentration inspection process by extending the exhaust time of the chamber 10.
On the other hand, the He concentration inspection step is performed after the inspection gas mixing step and the sealing step into the workpiece 90 performed in parallel with the chamber exhaust step. That is, the start time of the He concentration inspection process is determined by the time when the timers Ts3 to Ts7 for setting the time required for the series of the inspection gas mixing process and the sealing process are completed.

  For this reason, in response to extending the exhaust time of the chamber 10 (time measurement time of Ts1), the timers Ts3 to Ts7 also appropriately distribute the extension of the time measurement time of Ts1, and the time measurement end time of the timer Ts7 is set. The set value must be set to coincide with the time measurement end time of the timer Ts1. As described above, fine adjustment of the setting timer is complicated, so that setting of the timer requires skill, and in the process where the volume of the inspection work frequently changes, there is a problem that inspection failure occurs due to setting mistakes.

  In addition, in order to meet the recent high-precision inspection requirements, inspection methods and inspection devices that automatically respond to changes in the inspection environment are required, but the set times of many timers can be adapted to changes in the inspection environment. Since the fine adjustment is complicated, the conventional method cannot be realized.

In view of the above problems, the present invention performs fine adjustment of the required time due to changes in the inspection environment, that is, fine adjustment of each of the setting timers for setting the individual required times for each process constituting the airtight leak inspection. An object of the present invention is to provide an airtight leak inspection apparatus and an airtight leak inspection method that can be easily performed.
In addition to this, an airtight leak inspection apparatus and airtight leak which can save labor for setting each setting timer according to the type of work to be inspected and can automatically perform fine adjustment of the required time due to changes in the inspection environment. The purpose is to provide an inspection method.

In order to achieve the above object, according to the present invention, the time required for each process constituting the airtight leak test is added with a basic required time determined for each process and a fine adjustment amount resulting from a change in the inspection environment. The additional time required is determined as a product obtained by multiplying each additional time required by a certain variable and an adjustment coefficient defined for each process.
Therefore, if the time required for one of the processes is adjusted by changing the variable, the time required for the other processes is automatically adjusted accordingly. As a result, it is possible to set a fine adjustment amount due to a change in the inspection environment by adjusting one variable, and therefore it becomes easy to set each required time.

  For example, when the start time and end time of the processes executed in parallel are made to coincide with each other like the chamber exhaust process and the tracer gas (inspection gas) mixing and sealing process, the processes are executed in parallel. The adjustment coefficient is set so that the total amount of adjustment coefficients determined for each process is equal. By setting the adjustment coefficient in this way, regardless of the magnitude of the variable, the additional time required for the processes executed in parallel becomes equal, and the start time and the end time of these processes are adjusted to be the same. The

  In addition, the time required for each process that constitutes an airtight leak test is divided into a basic required time determined for each process and an additional required time that varies depending on changes in the inspection environment. It can be set regardless of environmental changes. This makes it possible to adjust the required time according to the type of workpiece to be inspected by automatically setting the basic required time based on the type of workpiece to be inspected. It is possible to omit the manual setting timer.

  For this reason, the airtight leak inspection apparatus according to the first embodiment of the present invention evacuates the inspection chamber containing the inspection object, encloses the tracer gas in the inspection object, and detects the tracer gas leaking from the inspection object. An airtight leak inspection apparatus for inspecting an airtight leak of an inspection object, each operation unit for executing each step constituting the airtight leak inspection, and a control unit for controlling the operation of each operation unit, The control unit includes a basic time measuring means for measuring a basic required time determined for each process as a required time for each process, and an extension for executing each process after the basic required time has elapsed. A variable setting means for setting a variable for expanding / contracting the required time, and an additional required time determined for each process by multiplying the set variable by an adjustment coefficient defined for each process. Additional time measuring means for measuring each of the corresponding basic required times after the completion of the measurement, and corresponding operations while the time required for each process is measured by each basic time measuring means and each additional time measuring means. Operate the unit.

  Here, the adjustment coefficient is configured so that, after the time measuring means for measuring the time required for the previous process finishes the time measurement, the time measuring means for measuring the time required for the next process starts measuring time. A plurality of the steps executed in the same manner, and the same time as the end time at which the steps are started at the same time as the start time for continuously executing the series of steps, and the series of steps are continuously executed. In other processes executed in parallel with a series of processes, the adjustment coefficient defined for the other processes and the total amount of adjustment coefficients defined for each of the series of processes are equally determined. .

Also, a basic time database for storing the basic required time for each type and / or type of the inspection object, an inspection object specifying means for specifying the type and / or type of the inspection object, and a basic required time are specified. It may be further provided with basic time setting means for reading out and setting from the database corresponding to the type and / or format.
Further, the adjustment coefficient database for storing the adjustment coefficient for each type and / or type of the inspection object, the inspection object specifying means for specifying the type and / or type of the inspection object, and the adjustment coefficient are specified. Adjustment coefficient setting means that reads out and sets from the database corresponding to the type and / or format may be further provided.

  Furthermore, the sensor may further include a sensor that detects a predetermined physical quantity that represents a factor that fluctuates the time required for each process, and the variable setting unit may set the variable according to the output value of the sensor.

  Further, in the airtight leak inspection method according to the second aspect of the present invention, the inside of the inspection chamber containing the inspection object is evacuated, the tracer gas is sealed in the inspection object, and the tracer gas leaking from the inspection object is detected. An airtight leak inspection method for inspecting an airtight leak of an object to be inspected, and measuring a basic required time set for each process as a required time for each process constituting the airtight leak inspection. An additional required time that is determined for each process by setting a variable that expands and contracts the additional required time to execute each process by extending after the required time elapses, and multiplying the set variable by the adjustment coefficient defined for each process Each time is counted after the corresponding basic required time is measured, and the corresponding process is executed during the measurement of each basic required time and each additional required time.

  Here, the adjustment coefficient starts a process at the same time as a series of a plurality of processes to be executed continuously, and a start time at which the series of processes are continuously executed, and continues the series of processes. For other processes executed in parallel with the series of processes, the adjustment coefficient determined for the other processes and the adjustments determined for each of the series of processes The total amount of coefficients is determined equally.

In addition, the basic required time is stored in advance for each type and / or type of the inspection object, the type and / or type of the inspection object is specified, and stored corresponding to the specified type and / or type. The basic required time may be determined as the basic required time to be timed as described above.
Further, the adjustment coefficient is stored in advance for each type and / or type of the inspection object, the type and / or type of the inspection object is designated, and the adjustment stored corresponding to the designated type and / or form. The coefficient may be used for calculating the additional required time.
Still further, the variable may be set according to the output of a sensor that detects a predetermined physical quantity representing a factor that varies the time required for each process.

For each process that constitutes an airtight leak inspection, it is possible to make fine adjustments of the required time due to changes in the inspection environment with one variable adjustment, which is a complicated operation that has been performed by skilled workers as before Can be easily performed without contradiction.
In addition, it is possible to adjust the required time that was performed according to the type of workpiece to be inspected by automatically setting the basic required time based on the type of workpiece to be inspected. It is possible to omit the manual setting timer.
Furthermore, by performing fine adjustment of the required time in accordance with a sensor that detects a change in the inspection environment, it is possible to realize an automatic inspection apparatus that does not rely on the skill and intuition of the operator.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic configuration diagram of an airtight leak inspection apparatus according to an embodiment of the present invention. In the airtight leak inspection apparatus 1 shown in FIG. 1, the same components as those in the airtight leak inspection apparatus described with reference to FIG. 5 are denoted by the same reference numerals, and the description of the same structural elements is omitted. To do.
The control unit 40 that controls the operation of each of the operation units 21 to 32 is realized by a programmable controller (PLC: Programmable Logic Controller). In the control unit 40, a basic time timer that counts a basic required time, which is a basic required time of each process for inspection, executed by each of the operation units 21 to 32 by a control program for controlling the operation thereof. Tr1 to Tr8 are provided.

In the basic timekeeping timers Tr1 to Tr8, among the time required for each corresponding process, fine adjustment time caused by the inspection environment (leakage amount of the previous inspection work, temperature, humidity, moisture brought into the work, etc.) The basic required time not included is set for each timer as the set time to be counted.
Here, the basic time measuring timer Tr1 is a timer that measures the basic time required for the evacuation process in the inspection chamber 10, that is, the process of opening the first valve 22 (or operating the chamber exhaust pump 21 together). It is.
The basic time counting timer Tr2 is a timer that measures the basic time required for the process of evacuating the work 90, that is, the process of opening the second valve 24 (or operating the work exhaust pump 23 together). .

The basic timekeeping timer Tr3 is a timer that measures the basic time required for the waiting time from the start of inspection to the introduction of He gas into the mixing tank 25. The basic timekeeping timer Tr4 is a He timer for the mixing tank 25. It is a timer that measures the basic time required for the process of introducing He gas into the mixing tank 25, which is performed after the end of the gas introduction waiting time.
The basic timekeeping timer Tr5 is a timer that measures the basic time required for waiting until the nitrogen gas is introduced into the mixing tank 25 after the He gas introduction process into the mixing tank 25, and the basic timekeeping timer Tr6. Is a timer that measures the basic time required for the step of introducing nitrogen gas into the mixing tank 25 that is performed after the end of the waiting time for introducing nitrogen gas into the mixing tank 25.

  The basic timekeeping timer Tr7 is performed after the nitrogen gas introduction process to the mixing tank 25. This is a timer for measuring the basic time required for the sealing process of the inspection gas produced in the mixing tank 25 into the work 90, and the basic timekeeping timer Tr8 is performed after the sealing process of the inspection gas into the work 90. This timer counts the basic time required for the concentration inspection process.

The control unit 40 finely adjusts the time required for each process according to the inspection environment described above. For this reason, an additional required time is provided for each basic required time according to the inspection environment, and a time obtained by adding the additional required time to the basic required time is set as an actual required time for each process.
In addition, the control unit 40 is provided with an additional time variable timer TrK for setting a variable time for expanding and contracting the additional required time according to the inspection environment.
Further, the control unit 40 includes an additional time adjustment counter that determines an additional time required for each process by multiplying one variable time Tv set in the additional time variable timer TrK by an adjustment coefficient determined for each process. Cn1 to Cn8 are provided. The additional time adjustment counters Cn1 to Cn8 are realized as a control program executed inside the control unit 40.

Such an additional time variable timer TrK and additional time adjustment counters Cn1 to Cn8 are pulses that generate a pulse for each set variable time Tv, for example, as described later with reference to FIG. By configuring as a generation circuit, the additional time adjustment counters Cn1 to Cn8 are configured as a counter module that counts pulses generated by the additional time variable timer TrK by the count number that is an adjustment coefficient determined for each counter. It is possible to realize.
Here, the additional time adjustment counter Cn1 is used to determine the additional required time to be added to the basic required time counted by the basic time clock timer Tr1, and the additional time adjustment counter Cn2 is the basic time measured by the basic time clock timer Tr2. The additional time adjustment counter Cn3 is used to determine the additional time required to be added to the basic time required by the basic time clock timer Tr3. Cn4 is used to determine an additional required time to be added to the basic required time measured by the basic time clock timer Tr4.

  The additional time adjustment counter Cn5 is used to determine the additional required time added to the basic required time measured by the basic time clock timer Tr5, and the additional time adjustment counter Cn6 is the basic required time measured by the basic time clock timer Tr6. The additional time adjustment counter Cn7 is used to determine the additional required time to be added to the time, and the additional time adjustment counter Cn7 is used to determine the additional required time to be added to the basic required time measured by the basic time clock timer Tr7. Is used to determine the additional required time to be added to the basic required time counted by the basic time clock timer Tr8.

  Then, the control unit 40 determines the actual required time of each process including the fine adjustment amount according to the inspection environment, the set value of the additional time variable timer, and the set value of the additional time adjustment counter determined for each process. And a value obtained by adding a set value of a basic timekeeping timer determined for each process. That is, the time required to execute each step is set to (the set value of the basic timekeeping timer + the set value of the additional time variable timer × the set value of the additional time adjustment counter).

The operation of each of the operation units 21 to 32 controlled by the control unit 40 that determines the time required for each process as described above will be described with reference to the operation time chart of each operation unit shown in FIG.
The control unit 40 causes the additional time adjustment counter Cn1 to start counting the additional required time when the basic time timer Tr1 finishes measuring the basic required time. In FIG. 2, the basic required time is indicated as Tri, and the additional required time is indicated as a setting value (TrK) of the additional time variable timer × a setting value (Cni) of the additional time adjustment counter (where i = 1 to 8). .

The chamber exhaust pump 21 is operated to open the first valve 22 from the start of the measurement of the basic required time by the basic time clock timer Tr1 to the end of the measurement of the additional required time by the additional time adjustment counter Cn1. As a result, the inside of the inspection chamber 10 is evacuated, and after the time is measured by the additional time adjustment counter Cn1, the evacuation inside the inspection chamber 10 is stopped by stopping the chamber exhaust pump 21 or closing the first valve 22. To do.
Similarly, the control unit 40 causes the additional time adjustment counter Cn2 to start measuring the additional required time when the basic time counting timer Tr2 finishes counting the basic required time. Then, the work exhaust pump 23 is operated to open the second valve 24 from the start of the measurement of the basic required time by the basic time timer Tr2 until the end of the additional required time by the additional time adjustment counter Cn2. As a result, the work 90 is evacuated, and after the time is measured by the additional time adjustment counter Cn2, the work evacuation pump 23 is stopped or the second valve 24 is closed to stop the evacuation of the work 90.

Further, the control unit 40 starts measuring the additional required time by the additional time adjustment counter Cn3 when the measurement of the basic required time by the basic time clock timer Tr3 that started timing at the start of the inspection is completed. Then, when the time measurement by the additional time adjustment counter Cn3 is finished, the measurement of the basic required time by the basic time measurement timer Tr4 is started, and when the time measurement by the basic time measurement timer Tr4 is completed, the additional time required by the additional time adjustment counter Cn4 is started. Start timing.
After the time required for the additional time adjustment by the additional time adjustment counter Cn3 is completed, the fourth valve 28 is opened to allow introduction of He gas into the mixing tank 25, and the additional time required by the additional time adjustment counter Cn4. After the time measurement is completed, the fourth valve 28 is closed and the introduction of He gas is prohibited.

Further, the control unit 40 starts counting the basic required time by the basic time clock timer Tr5 when the time measurement by the additional time adjustment counter Cn4 is completed, and when the time measurement by the basic time clock timer Tr5 is completed, the control unit 40 adds the additional time adjustment counter Cn5. Start counting the additional time required by. Then, when the time measurement by the additional time adjustment counter Cn5 is completed, the measurement of the basic required time by the basic time clock timer Tr6 is started, and when the time measurement by the basic time clock timer Tr6 is completed, the additional required time by the additional time adjustment counter Cn6 is started. Start timing.
The control unit 40 then opens the fifth valve 30 and permits the introduction of the nitrogen gas into the mixing tank 25 after the time required for the additional time by the additional time adjustment counter Cn5 has been completed. After the time required for the additional time by Cn6 is finished, the fifth valve 30 is closed and the introduction of nitrogen gas is prohibited.

  Further, the control unit 40 starts counting the basic required time by the basic time clock timer Tr7 when the time measurement by the additional time adjustment counter Cn6 is completed, and when the time measurement by the basic time clock timer Tr7 is completed, The timing of the additional required time by Cn7 is started. Then, the third valve 26 is opened from the time when the basic time measuring timer Tr7 starts measuring the basic required time to the time when the additional required time is counted by the additional time adjustment counter Cn7 which is started after the time measurement ends. Thus, the inspection gas is allowed to be enclosed in the workpiece 90, and the third valve 26 is closed after the time measurement of the additional time adjustment counter Cn7 is completed, thereby prohibiting the inspection gas from being enclosed.

  Finally, when the time measurement by the additional time adjustment counter Cn7 ends, the control unit 40 starts to measure the basic required time by the basic time clock timer Tr8, and when the time measurement by the basic time clock timer Tr8 ends, the additional time adjustment counter The timing of the additional required time by Cn8 is started. Then, after the basic time measuring timer Tr8 starts to measure the basic required time, the sixth valve 32 is kept open until the additional time adjustment counter Cn8 starts measuring the required additional time after the time measurement ends. The introduction of the inspection gas into the He detector 31 is permitted, and the introduction of the inspection gas is prohibited by closing the sixth valve 32 after the time measurement of the additional time adjustment counter Cn8 is completed.

  Therefore, the basic time timers Tr1 to Tr8 constitute basic time timer means according to the claims of the present application, and the additional time variable timer TrK constitutes variable setting means according to the claims of the present application, and the additional time. The adjustment counters Cn1 to Cn8 constitute additional time measuring means according to the claims of the present application.

By configuring the control unit 40 as described above, the additional required time, which is a fine adjustment amount of the required time for each process according to the inspection environment, is adjusted for each process only by adjusting one additional time variable timer TrK. Fluctuate according to the ratio between the set values set in the additional time adjustment counters Cn1 to Cn8.
An example of adjusting the required time for each process by the additional time variable timer TrK will be described with reference to FIG.

As shown in the third column of the table shown in FIG. 3, the basic time clock timer Tr1 and the additional time adjustment counter Cn1 for controlling the time required for the chamber exhaust process are set to Tr1 = 30 seconds and Cn1 = 20, and the work exhaust process The basic time counting timer Tr2 and the additional time adjustment counter Cn2 for controlling the required time are set to Tr2 = 20 seconds and Cn1 = 18.
Further, the basic timekeeping timers Tr3 to Tr6 and additional time adjustment counters Cn3 to Cn6 for controlling the time required for the inspection gas mixing process are Tr3 = 3, Tr4 = 6, Tr5 = 3, Tr6 = 8, Cn3 = 9, Cn4. = 0, Cn5 = 9 and Cn6 = 0.
Further, the basic time timer Tr7 for controlling the time required for the test gas filling process and the additional time adjustment counter Cn7 are set to Tr7 = 10 seconds and Cn7 = 2, and the basic time clock timer for controlling the time required for the He concentration test process. Tr8 and additional time adjustment counter Cn8 are set to Tr8 = 10 seconds and Cn8 = 0.

  Here, the actual required time Tri ′ of each process finely adjusted according to the inspection environment is calculated as Tri ′ = Cni × TrK + Tri (where i = 1 to 8). Therefore, when the additional time variable timer TrK = 0 seconds is set without fine adjustment according to the inspection environment, the required times Tr1 ′ to Tr8 ′ are equal to the basic time timers Tr1 to Tr8, respectively. (See the fourth column of the table)

On the other hand, when fine adjustment is performed (that is, when the additional time variable timer TrK is set to a value other than 0 seconds), the ratio between the set values of the additional time adjustment counters Cn1 to Cn8 determined for each process. Each additional required time (Cn1 × TrK to Cn8 × TrK) having a length according to 20: 18: 9: 0: 9: 0: 2: 0 is added to the basic required time Tr1 to Tr8 of each process. Is done.
The fifth column of the table shows an example of calculating the required times Tr1 ′ to Tr8 ′ of each process when the additional time variable timer TrK is set to 1 second.

The mixed gas exhausting and sealing process comprises a series of a plurality of processes that are executed continuously, and the time measuring means for measuring the time required for the next process is a time measuring means for measuring the time required for the previous process. Is configured to start timing (for example, the timing of the basic time counting timer Tr3 that counts the time required for the He introduction waiting time, which is the previous process, and each additional time adjustment counter Cn3 is terminated). Later, the basic time timer Tr4 that counts the time required for the He introduction process, which is the next process, and each additional time adjustment counter Cn4 start timing). The set times of the basic timekeeping timers Tr3 to Tr7 that determine the basic required time of these series of processes are the basic time that determines the required time of the chamber exhaust process executed in parallel with these series of processes. It is set equal to the set time of the time timer Tr1.
Therefore, the chamber exhaust process and the series of mixed gas exhaust and sealing processes that are started simultaneously from the start of the airtight leak test are performed at the same time when the value of the additional time variable timer TrK is set to 0 seconds. Exit.

  Furthermore, the set value (20) of the additional time adjustment counter Cn1 for determining the additional time required for the chamber exhaust process is an additional time adjustment counter for determining the additional required time for the series of gas mixture exhaust and sealing processes that are executed continuously. It is set equal to the sum (9 + 0 + 9 + 0 + 2) of the set values of Cn3 to Cn7. Therefore, in the chamber exhaust process and the series of mixed gas exhaust and sealing processes, the required time is adjusted so that the process is completed at the same time regardless of the value set in the additional time variable timer TrK. The

  Similarly, the set times of the basic time timers Tr3 to Tr6 that determine the basic required time of the series of mixed gas exhausting processes are the sum of the set times of the basic time clock timer Tr2 that determines the basic required time of the work exhaust process. The additional time adjustment counters Cn3 to Cn6 that are set to be equal and determine the additional time required for the exhaust process of the mixed gas are added time adjustment counters that determine the additional time required for the exhaust process of the work exhaust process. It is set to be equal to the set value of Cn2.

  FIG. 4 is a part of a ladder circuit diagram for realizing the additional time variable timer TrK, basic time clock timers Tr1 to Tr8, and additional time adjustment counters Cn1 to Cn8. Here, a basic time timer Tr1 and an additional time adjustment counter Cn1 for controlling the exhaust process of the chamber 10 will be described as an example. Note that, by compiling the ladder circuit shown in FIGS. 4B and 4C with a predetermined compiler, the control unit 40 generates a control program for realizing the basic timekeeping timer Tr1 and the additional time adjustment counter Cn1. Is done.

  As shown in FIG. 4A, the additional time variable timer TrK is composed of a timer element that operates in a timed manner, and is wired so as to excite the coil with its own b contact (non-excitation contact). Therefore, the timer TrK is excited at every set time (in the example shown, 1 second) and immediately repeats the non-excited operation. Therefore, the timer TrK becomes a pulse generation circuit that generates pulses at intervals of the set time. .

  The additional time adjustment counter Cn1 shown in FIG. 4B is a counter element that operates (becomes ON) when a predetermined number of pulses are input. Since the a contact (excitation contact) of the basic timekeeping timer Tr1 that operates in a time limit and the a contact of the additional time variable timer TrK are inserted as serial conditions at the input of the additional time adjustment counter Cn1, the additional time adjustment counter Cn1 After the time measurement of the basic time counting timer Tr1, the operation state is entered after the set time by the additional time variable timer TrK has passed a predetermined number of times (20 times in the illustrated example).

  Therefore, as shown in FIG. 4C, by inserting the b contact of the additional time adjustment counter Cn1 into the conditions of the chamber exhaust operation, the time measurement of the basic time clock timer Tr1 is completed, and thereafter the additional time variable timer The chamber exhaust operation can be terminated after the additional time adjustment counter Cn1 measures the required additional time determined by the set value of TrK × additional time adjustment counter Cn1.

  Further, the airtight leak inspection apparatus 1 includes a basic time database 41 that stores the basic required time measured by the basic time measuring timers Tr1 to Tr8 for each type, type, and / or model number of the work to be inspected. The control unit 40 reads and sets each basic required time from the basic time database 41 corresponding to the specified type and the like, and a workpiece specifying unit (not shown) that specifies the type and the like of the workpiece currently inspected. And a basic time setting unit (not shown). Then, the control unit 40 may automatically set the basic timekeeping timers Tr1 to Tr8 according to the type of workpiece specified by the workpiece specifying unit.

  Further, the airtight leakage inspection apparatus 1 includes an adjustment counter database 42 that stores the set values of the additional time adjustment counters Cn1 to Cn8 for each type, type, and / or model number of the workpiece that is the inspection object. Reference numeral 40 denotes a work designation unit (not shown) for designating the type of work currently inspected, and an adjustment counter that reads and sets each counter setting value from the adjustment counter database 42 in accordance with the designated type. It is good also as comprising a setting part (not shown). Then, the control unit 40 may automatically set the additional time adjustment counters Cn1 to Cn8 according to the type of workpiece specified by the workpiece specifying unit.

  Further, the airtight leakage inspection apparatus 1 may include a sensor that detects a physical quantity (a leakage amount of the previous inspection work, temperature, humidity, moisture brought into the work, etc.) indicating an inspection environment that affects the time required for each process. Well (not shown), at this time, the additional time variable timer TrK may change the variable set time in accordance with the output value of the sensor.

  INDUSTRIAL APPLICABILITY The present invention can be used for an apparatus and a method for performing an airtight leak inspection of an inspection object in a vacuum using a leakage inspection medium (tracer gas) such as helium (He) gas.

1 is a schematic configuration diagram of an airtight leak inspection apparatus according to an embodiment of the present invention. It is a time chart of each operation | movement unit of the airtight leak test | inspection apparatus shown in FIG. It is a table | surface which shows the example of adjustment of the required time for every process by the additional time variable timer TrK. FIG. 2 is a part of a ladder circuit diagram that realizes an additional time variable timer, a basic time timer, and an additional time adjustment counter shown in FIG. 1. It is a schematic block diagram of the conventional airtight leak test | inspection apparatus which performs a vacuum type helium leak test | inspection. It is a table | surface which shows the example (the 1) of a setting of each setting timer used in order to control an operation unit. It is an operation | movement time chart by the example of a setting shown in FIG. It is a table | surface which shows the example (the 2) of a setting of each setting timer used in order to control an operation | movement unit. It is an operation | movement time chart by the example of a setting shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Airtight leak inspection apparatus 10 Inspection chamber 21 Chamber exhaust pump 22, 24, 26, 28, 30, 32 Valve 23 Work exhaust pump 40 Control unit 90 Work Tr1-Tr8 Basic time timer Cn1-Cn8 Additional time adjustment counter TrK Additional time Variable timer

Claims (10)

The inside of the inspection chamber containing the inspection object is evacuated, a tracer gas is sealed in the inspection object, and the tracer gas leaking from the inspection object is detected to inspect the airtight leak of the inspection object. In the airtight leak inspection apparatus, the airtight leak inspection apparatus includes each operation unit that executes each step constituting the airtight leak inspection, and a control unit that controls the operation of each operation unit,
The control unit is
Basic time measuring means for measuring the basic required time determined for each of the processes as the required time of each of the processes;
A variable setting means for setting a variable that extends after each basic required time elapses and expands or contracts an additional required time to execute each of the steps;
An addition for measuring each of the required additional times determined for each of the processes by multiplying the set variable by an adjustment coefficient determined for each of the processes after the timing of the corresponding basic required time is completed. Time counting means;
And operating the corresponding operation unit while measuring the time required for each step by each basic time measuring means and each additional time measuring means,
Airtight leak inspection device characterized by. A series of continuously executed, wherein the time measuring means for measuring the time required for the next process is configured to start time measurement after the time measuring means for measuring the time required for the previous process has finished measuring time. A plurality of said steps;
The process is started at the same time as the start time for continuously executing the series of processes, and the operation is ended at the same time as the end time at which the series of processes are continuously executed. For the other steps performed in
The airtight leak inspection apparatus according to claim 1, wherein the adjustment coefficient defined for the other process and the total amount of the adjustment coefficient defined for each of the series of processes are equally determined. A basic time database for storing the basic required time for each type and / or type of the inspection object;
Inspection object specifying means for specifying the type and / or form of the inspection object;
Basic time setting means for reading out and setting the basic required time from the database corresponding to a specified type and / or format;
The airtight leak inspection apparatus according to claim 1, further comprising: An adjustment coefficient database for storing the adjustment coefficient for each type and / or type of the inspection object;
Inspection object specifying means for specifying the type and / or form of the inspection object;
Adjustment coefficient setting means for reading out and setting the adjustment coefficient from the database corresponding to a specified type and / or format;
The airtight leak inspection apparatus according to claim 1, further comprising: A sensor for detecting a predetermined physical quantity representing a factor that varies the time required for each step;
The hermetic leak inspection apparatus according to claim 1, wherein the variable setting unit sets the variable according to an output value of the sensor. The inside of the inspection chamber containing the inspection object is evacuated, a tracer gas is sealed in the inspection object, and the tracer gas leaking from the inspection object is detected to inspect the airtight leak of the inspection object. In the air leak inspection method,
The basic time required for each process is counted as the time required for each process constituting the airtight leak test,
Set a variable that expands and contracts the additional time required to execute each step by extending after each basic time elapses,
Each of the additional required times determined for each of the processes by multiplying the set variable by an adjustment coefficient determined for each of the processes, respectively, after the timing of the corresponding basic required time,
Executing each of the corresponding steps during the counting of each basic required time and each additional required time,
Airtight leak inspection method characterized by A series of a plurality of said steps carried out in succession;
The process is started at the same time as the start time for continuously executing the series of processes, and the operation is ended at the same time as the end time at which the series of processes are continuously executed. For the other steps performed in
7. The airtight leak inspection method according to claim 6, wherein the adjustment coefficient defined for the other process and the total amount of the adjustment coefficient defined for each of the series of processes are equally determined. The basic required time is stored in advance for each type and / or type of the inspection object,
Specify the type and / or type of the inspection object,
The basic required time stored corresponding to the designated type and / or format is determined as the basic required time to be timed.
The airtight leakage inspection method according to claim 6 or 7, characterized in that The adjustment coefficient is stored in advance for each type and / or type of the inspection object,
Specify the type and / or type of the inspection object,
The adjustment coefficient stored corresponding to the specified type and / or format is used for calculating the additional time required.
The airtight leakage inspection method according to claim 6 or 7, characterized in that   10. The airtightness according to claim 6, wherein the variable is set in accordance with an output of a sensor that detects a predetermined physical quantity that represents a factor that varies the time required for each process. Leak inspection method.

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