KR20080066686A - Insulation inspecting device and insulation inspecting method - Google Patents

Abstract

An insulation inspecting device and method for inspecting insulation of spark of a circuit board with higher accuracy. The insulation inspecting device (1) is used for inspecting the insulation of a circuit board (10) where wiring patterns (P) are formed. The device (1) comprises selecting means (2) for selecting one of the wiring patterns as a first inspection region (T1 shown in Fig.2) and the other wiring patterns as a second inspection region (T2 shown in Fig. 2), power supply means (3) connected to the second inspection region and adapted to apply a voltage to the second inspection regions as to set a predetermined potential difference between the first and second inspection regions, first current detecting means (4) connected to the first inspection region so as to detect a current flowing to the first inspection region, and judging means (7) for comparing the current value detected by the first current detecting means with a predetermined reference value and judging that the circuit board is an acceptable one or a rejected one on the basis of the result of the comparison.

Description

Insulation inspection device and insulation inspection method {INSULATION INSPECTING DEVICE AND INSULATION INSPECTING METHOD}

The present invention relates to an insulation inspection apparatus and an insulation inspection method, and more particularly, to an insulation inspection apparatus and an insulation inspection method capable of quickly and accurately performing insulation inspection of a circuit board on which a plurality of wiring patterns are formed. It is about.

Conventionally, insulation inspection of a circuit board having a plurality of wiring patterns is performed by determining whether the circuit board is good or defective by determining whether the insulation state between the wiring patterns is sufficient (whether sufficient insulation is ensured). Was being judged.

In such a conventional insulation inspection apparatus, by applying a relatively high voltage (for example, 200 V) between two wiring patterns to be inspected, the resistance value between the wiring patterns is calculated, and both parts of the insulation state are based on this resistance value. Was judging.

However, in the conventional insulation inspection apparatus, the inspection is started when a stable time elapses after a predetermined time has been applied after the application of the predetermined voltage. Therefore, if a spark occurs while the predetermined voltage is being applied, an incorrect resistance value is calculated. The problem was that the quality of the insulation could not be determined accurately.

In order to solve such a problem, this inventor created the insulation inspection apparatus and method disclosed by the patent document 1 filed previously.

Patent Document 1: Japanese Patent Publication No. 3546046 (Issuance Date: July 21, 2004) In the insulation inspection apparatus and method disclosed in Patent Document 1, a predetermined DC voltage is applied between a pair of wiring patterns. By detecting a voltage that changes from the start of application to a predetermined voltage value, the spark is detected from the voltage change, and the spark is detected by detecting the voltage drop when the spark is generated. As described above, the spark can be detected by detecting the voltage change in the increase period of the applied voltage, thereby solving the above problem.

Disclosure of the Invention

Problems to be Solved by the Invention

However, this patent document 1 does not describe the inspection regarding the situation of a spark, etc.

Therefore, in consideration of the situation of sparks, etc., the creation of the insulation inspection apparatus and insulation inspection method which can test more accurately with respect to the spark of a circuit board was calculated | required.

Means to solve the problem

An object of this invention is to provide the insulation inspection apparatus which can test | inspect more accurately regarding the spark of a circuit board.

Moreover, an object of this invention is to provide the insulation inspection method which can test | inspect more accurately regarding the spark of a circuit board.

In view of the above object, the insulation inspection apparatus according to the present invention is an insulation inspection apparatus for performing insulation inspection of a circuit board on which a plurality of wiring patterns are formed. Electing means for electing as the first inspection unit and selecting all wiring patterns to be inspected other than the first inspection unit as the second inspection unit, and setting a predetermined potential difference between the first inspection unit and the second inspection unit. In order to be connected to the second inspection unit, a power supply means for applying a voltage to the second inspection unit, current detection means for detecting a current flowing between the first inspection unit and the second inspection unit, and the current detection means detects Determination means for comparing the current value with a predetermined reference value and determining the circuit board as a good or defective product based on the comparison result And that the feature.

Moreover, in the said insulation inspection apparatus, the said 2nd inspection part may consist of wiring patterns other than the wiring pattern of the said 1st inspection part, and all these wiring patterns may be connected in parallel.

In the insulation inspection apparatus, the current detecting means may be connected in series with the first inspection unit or the second inspection unit.

Moreover, in the said insulation inspection apparatus, the said selection means selects all the said some conductor patterns as a 1st inspection part one by one, and the determination of the said inferior goods makes the said circuit board into inferior goods when the said electric current value is larger than the said reference value. You may judge.

In the insulation inspection apparatus, the current detection means has a first current detection means and a second current detection means having two different ranges, and the first current detection means is a spark associated with the first inspection unit. The second current detection means may be formed to measure the insulation resistance value between the first inspection unit and the second inspection unit.

The insulation inspection apparatus may further include display means for displaying the current value detected by the first current detection means in time series.

Moreover, in the said insulation inspection apparatus, the said determination means has a spark detection part and a power calculation part, The said spark detection part detects a spark generation based on the measured current value from the said 1st current detection means, The said power calculation part, The state of a spark may be detected based on the measured current value from said 1st current detection means, and the measured voltage value from the voltage detection part which detects the voltage of the said 1st inspection part.

Moreover, in the said insulation inspection apparatus, the said determination means has a resistance calculation part, and a resistance value is based on the measurement current value from the said 2nd current detection means, and the measurement voltage value from the voltage detection part which detects the voltage of the said 1st inspection part. May be calculated.

The insulation inspection method according to the present invention is an insulation inspection method for performing insulation inspection of a circuit board on which a plurality of wiring patterns are formed, wherein one wiring pattern to be inspected from the plurality of wiring patterns is used as the first inspection portion. In addition to electing, selecting all wiring patterns to be inspection targets other than the first inspection unit as the second inspection unit, and generating the predetermined potential difference between the first inspection unit and the second inspection unit, the second inspection unit Applying a voltage to the second inspecting unit, detecting a current flowing between the first inspecting unit and the second inspecting unit, and comparing a current value flowing through the first inspecting unit with a predetermined reference value The result of the comparison includes determining the circuit board as good or defective.

In addition, the recording medium according to the present invention selects, as a first inspection unit, one wiring pattern to be inspected from the plurality of wiring patterns to a computer which performs insulation inspection of a circuit board on which a plurality of wiring patterns are formed. At the same time, selecting all wiring patterns to be inspected other than the first inspection unit as the second inspection unit, and in order to generate a predetermined potential difference between the first inspection unit and the second inspection unit, a voltage is applied to the second inspection unit. Applying a step, detecting a current flowing between the first test part and the second test part in a state where a voltage is applied to the second test part, comparing the current value flowing through the first test part with a predetermined reference value, Insulation inspection method program of the circuit board for performing the step of determining the circuit board as good or defective based on the comparison result A recording medium readable by a computer recorded.

Effects of the Invention

According to this invention, the insulation inspection apparatus which can test | inspect more accurately with respect to the spark of a circuit board can be provided.

And according to this invention, the insulation inspection method which can test | inspect more accurately with respect to the spark of a circuit board can be provided.

1 shows a schematic configuration diagram of an example of an insulation inspection apparatus according to the present invention.

FIG. 2A is a diagram showing an example of a combination of the first inspection unit and the second inspection unit by the election means of FIG. 1, wherein the uppermost wiring pattern P1 of the switch group SWs is elected as the first inspection unit T1. The wiring patterns P2 to P5 are selected as the second inspection unit T2.

FIG. 2B is a view showing an example of a combination of the first inspection unit and the second inspection unit by the selecting means of FIG. 1, wherein the wiring pattern P4 is selected as the first inspection unit T1, and the wiring patterns P1 to P3, P5) This state is selected as the second inspection unit T2.

3 is a schematic configuration diagram showing the function of the determination means of FIG. 1.

4 is a graph showing changes in current values in good and defective circuit boards. Here, the two-dot broken line indicates the reference value A.

5A is a graph showing changes in current values in a circuit board of good and defective products.

FIG. 5B has shown the difference of the electric current value shown in FIG. 5A. Here, two one-point dashed lines indicate an allowable range.

6 is a graph showing changes in current values in a circuit board of good and defective products. Here, the state of the change in time tl, t2 is shown.

FIG. 7 is a flowchart showing an inspection method performed in the insulation inspection apparatus of FIG. 1.

(Explanation of the sign)

1: insulation inspection device

2: election means

3: power means

4: first current detecting means

5: second current detecting means

6: voltage detection means

7: determination means

8 display means

9: control means

10: memory means

P: wiring pattern

SW: Switch

SWs: Switch group

T1: 1st inspection part

T2: 2nd inspection part

CP: Contact pin

Implement the invention  Best form for

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of the insulation inspection apparatus and insulation inspection method which concern on this invention is described, referring an accompanying drawing. In addition, the same code | symbol is attached | subjected about the same element in drawing, and the overlapping description is abbreviate | omitted.

The term "circuit board" described in this application document is not limited to a printed wiring board, For example, a flexible board | substrate, a multilayer wiring board, the electrode board for liquid crystal displays or a plasma display, and the package substrate and film carrier for semiconductor packages The board | substrate to which various wiring etc. are performed is named generically. That is, the circuit board includes all the boards that can be subjected to insulation inspection.

[Insulation test device]

FIG. 1: is a figure explaining an example of schematic structure of the insulation inspection apparatus 1 which concerns on this invention. Here, the insulation inspection apparatus 1 consists of each element except the circuit board CB which is an inspection object from the element shown in FIG. That is, the insulation inspection apparatus 1 includes the control means 9, the display means (monitor: 8), the switch group SWs, the power supply means 3, the first current detection means 4, The second current detecting means 5 and the voltage detecting means 6 are provided. This control means 9 has a selection means (also called "SW switching control means"), a determination means 7, and a storage means 10. The control means 9 consists of a normal computer, the selection means 2 and the determination means 7 consist of the CPU, and the storage means 10 stores the computer program which performs this insulation inspection method. ROM or working memory RAM. The switch group SWs has a plurality of sets of a pair of switches SW1 and a switch SW2.

On the other hand, conductive patterns P1 to P5 (generally referred to as "P") are formed in the circuit board CB to be inspected. In order to simplify the drawing and make it easier to understand, in the figure, only five kinds of wiring patterns of linear wiring patterns P1, P2, T-shaped wiring patterns P3 and cross wiring patterns P4, P5 are illustrated as a pattern P. FIG. . Here, in the circuit board CB which is a good article, each of the patterns P1 to P5 is in an electrically independent state, and maintains a predetermined insulation resistance between adjacent patterns.

The insulation inspection apparatus 1 has a plurality of contact pins CP connected to the pairs of SW1 and SW2 constituting the switch group SWs, and each contact pin has each wiring pattern P1 to circuit board CB. Each electrical contact is made to P5), and the inspection of the insulation state or the conduction state of each wiring pattern is enabled.

The basic principle of the inspection performed by the insulation inspection apparatus 1 is to select the pattern P of the circuit board CB as the first inspection unit T1 and the second inspection unit T2 according to a predetermined rule, By detecting a current flowing in the first inspection unit T1 while applying a predetermined voltage to the inspection unit T2 and generating a predetermined potential difference between the first inspection unit T1 and the second inspection unit T2, To run a more accurate test. Here, the first inspection unit includes one (single) wiring pattern (also referred to as an "inspection pattern") that is a test target selected from a plurality of wiring patterns (in the drawings, P1 to P5) of the circuit board CB. Is done. The 2nd test part T2 consists of all the remaining wiring patterns which are test objects other than the 1st test part T1 (it is also called "the whole pattern other than a test pattern"). In the inspection, the plurality of wiring patterns included in the circuit board CB are sequentially selected as the first inspection unit, and each time, the insulation inspection is performed between the second inspection unit, and all the wiring patterns are selected as the first inspection unit and inspected. When it ends.

Hereinafter, each element which comprises the insulation inspection apparatus 1 is demonstrated. The electoral means 2 selects one wiring pattern to be inspected as the first inspection unit (inspection pattern) T1 from among the plurality of wiring patterns included in the circuit board CB. At the same time, all the remaining wiring patterns which are inspection targets other than the wiring pattern which is the first inspection unit T1 are selected as the second inspection unit T2. In this state, after the insulation inspection is performed between the first inspection unit T1 and the second inspection unit T2, one of the wiring patterns to be inspected from among the patterns not yet selected as the first inspection unit T1 is selected. It selects as the test | inspection part T1, and selects all remaining wiring patterns used as a test object as the 2nd test | inspection part T2. This step is repeated below.

A concrete selection method is performed by the selection means 2 using switch groups SWs having a plurality of switch elements SW1 and SW2 and selection means 2 (SW switching control means) for switching control of each switch element. The plurality of wiring patterns are selected by either the first inspection unit T1 or the second inspection unit T2 by the on / off switching operation of the respective switch elements SW1 and SW2.

For example, in FIG. 2A, the wiring pattern P1 at the top of the switch group SWs is selected as the first inspection unit (inspection pattern) T1, and the wiring patterns P2 to other than the wiring pattern P1 are selected. P5) The state which was selected as this 2nd inspection part (all patterns other than a to-be-tested pattern) T2 is shown. In FIG. 2B, the wiring pattern P4 is selected as the first inspection unit T1, and the wiring patterns P1 to P3 and P5 other than the wiring pattern P4 are selected as the second inspection unit T2. have.

Each contact pin CP electrically connected to each wiring pattern P can be connected to the power supply means 3 via the switch SW1, and the first current detection means 4, via the switch SW2, It is possible to connect to the second current detecting means 5 and the voltage detecting means 6.

In FIG. 2A, the wiring pattern P1 elected as the first inspection unit T1 is connected to the first current detecting means 4 and the second current detecting means 5 by turning the switch SW2 ON. It is connected to the voltage detection means 6. The wiring patterns P2 to P5 elected as the second inspection unit T2 are connected to the power supply means 3 when the switch SW1 is turned ON, respectively. At the front end of the first current detecting means 4, a switch SWa is formed at the front end of the switch SWa and the voltage detecting means 6, and under the control of the control means 9, at the time of each detection. The switch may be turned ON.

The wiring patterns P2 to P5 elected as the second inspection unit T2 are electrically connected in parallel to each other through the respective SW1s. By parallel connection in this manner, all of the wiring patterns P2 to P5 of the second inspection unit T2 can be set to the same potential, and spark generation between the wiring patterns can be prevented even with a wiring pattern having a large and complicated area.

Election of the wiring pattern P performed under the control of the elector 2 means that the wiring pattern P1 once selected as the first inspection unit T1 is elected again as a subsequent first inspection unit T1. It is set so that nothing happens. For this reason, the 1st inspection part T1 selects all the wiring patterns P one by one sequentially.

The power supply means 3 is connected to the second inspection unit T2 so that a predetermined voltage can be applied to each of the second inspection unit T2 through each SW1 in order to set a predetermined potential difference between the first inspection unit T1 and the second inspection unit T2. have. The power supply means 3 changes the potential of the second inspection unit T2, so that the second inspection unit T2 has a potential different from that of the first inspection unit T1.

The power supply means 3 only needs to generate a predetermined potential difference between the first inspection unit T1 and the second inspection unit T2, and is not particularly limited to a direct current power source or an alternating current power source. However, in order to detect the change of the current value in the 1st current detection means 4 mentioned later more correctly, it is preferable that it is a variable DC power supply.

The predetermined potential difference applied by the power supply means 3 is not particularly limited, but is preferably set to generate a potential difference of 1 to 10 V / µS. This is because by using the potential difference in this range, it is possible to detect the spark in a short time and accurately.

As shown in FIG. 2A, the first current detecting means 4 is connected in series to the first inspection unit (wiring pattern P1) T1 via the switch SW2 and the contact pin CP, and the first current detecting means 4 is connected in series. The current of the inspection unit T1 is detected. The 1st current detection means 4 uses the ammeter which can measure a current value. The electric current difference detected by the first current detecting means 4 generates a potential difference between the first inspecting section T1 and the second inspecting section T2 by applying a predetermined voltage to the second inspecting section T2. Under the influence, it is a current flowing through the first detection unit T1.

For this reason, when the electric current value measured by the 1st electric current detection means 4 showed the change of the electric current value more than predetermined value, or the electric current value more than predetermined value, a spark generate | occur | produces between 1st inspection part T1 and 2nd inspection part T2. It will be shown. In other words, the spark between the two inspection sections can be detected by the current value measured by the first current detection means 4.

Since the first current detecting means 4 is connected to the first inspection part (inspection pattern) T1 side, the second inspection part (all wiring patterns other than the inspection pattern) T2 and the contact pin CP are connected. Sparks resulting from poor contact are not detected by the first current detecting means. In addition, since the voltage is not applied to the first inspection unit T1 and is grounded through the contact pin CP, the switch SW2, the first current detection means 4, and the second current means, the first inspection unit (Inspection pattern) Sparks resulting from poor contact between T1 and the contact pin CP do not occur.

And the spark which arises between the 2nd test part (all wiring patterns other than a to-be-tested pattern) T2 to which predetermined voltage was applied, and the metal frame etc. of these wiring patterns vicinity (in this application document, a "pseudo spark" Even if there is an occurrence of a current), since no current flows to the first inspection unit T1 side, the insulation inspection apparatus 1 does not detect such a pseudo spark. In this way, the insulation inspection apparatus 1 prevents the occurrence of sparks occurring other than between the first inspection portion T1 and the second inspection portion T2 and does not detect this even if it occurs.

Although the measuring performance is not specifically limited as long as this 1st electric current detection means 4 can measure the electric current value at the time of a spark, it is preferable that it can detect the electric current value of 0.1-10 mA. On the other hand, the current value detected by the first current detecting means 4 is sent to the determining means 7 described later.

The second current detection means 5 is connected in series with the first inspection unit T1 and detects a current flowing therein. Although the 2nd current detection means 5 is common in the point which can measure the electric current which flows in the 1st test | inspection part T1 similarly to the above-mentioned 1st current detection means 4, 1st current detection means 4 ) Are different in that they have the ability to measure smaller currents compared to

Since the current value flowing between the first inspection unit T1 and the second inspection unit T2 can be reliably measured by having the second current detection unit 5, the first current detection unit 5 can be used by using the voltage detection unit 6 described later. The resistance value between the inspection unit T1 and the second inspection unit T2 can be calculated.

The current measuring capability of the second current detecting means 5 is not particularly limited as long as the current value necessary for calculating the resistance value between the first and second inspection units T1 and T2 as described above can be measured, and is 0.1. It is preferable that a current value of ˜20 μA can be detected. The current value measured by the second current detection means 5 is sent to the determination means 7.

The first current detecting means 4 is mainly formed to detect spark generation associated with the first inspecting portion (inspection pattern), and the second current detecting means 5 is insulated between the first inspecting portion and the second inspecting portion. It is formed to measure the resistance value. However, it should be noted that depending on the performance of the ammeter used, the first current detection means 4 and the second current detection means 5 may be used together by one ammeter.

The voltage detection means 6 is connected to the 1st inspection part T1, and detects the voltage of the 1st inspection part T1. This voltage detection means 6 can use the voltmeter which can measure the voltage value applied to the 1st test | inspection part T1. The voltage value measured by this voltage detection means 6 is sent to the determination means 7.

The determination means 7 receives the measured current value from the 1st current detection means 4 and the 2nd current detection means 5, and the measured voltage value from the voltage detection means 6, respectively, and based on these measured values, It is determined whether the circuit board is defective. 3 is a schematic configuration diagram showing the function of the determination means 7. The determination means 7 has a spark detection unit 71, a power calculation unit 73, a resistance calculation unit 74, an insulation determination unit 75, and a transmission unit 72.

The determination performed by this determination means 7 compares with the reference value set in advance on the basis of the current value from the first current detection means 4, and determines the good or defective product according to the comparison result. It is made by having. As a specific comparative method which this spark detection part 71 performs, the following three methods are mentioned, for example.

As a first method, it is a method of directly comparing a current value detected by the first current detecting means 4 with a reference value, and determining as spark generation when the detected current value is larger than a predetermined value.

For example, in FIG. 4, the change in the current value represented by the broken line represents the change in the good circuit board, and the change in the current value represented by the solid line represents the change in the defective circuit board which is the inspection target, and exceeds the reference value A. It shows that one part is a spark generation point. Although the reference value A in the case of using this 1st method is not specifically limited, It is set to 0.1-1.0 mA.

On the other hand, in the case of judging by this first method, the power supply means 3 is a variable voltage power supply, and forms an appropriate circuit so as to control the rise of the current value at the instant of applying the voltage not to exceed the predetermined value. desirable. This determination means 7 is, for example, an AD converter circuit for sequentially converting measured current values (analog values) from the first current detection means 4 and the second current detection means 5 into digital current data. And a comparison circuit (not shown) which inputs the digital current data with the digital reference data of the reference value A and outputs a logic height "1" when the measured digital current data exceeds the digital reference data. Can be configured.

As a second method, a change in the current value is obtained as a reference current change value (B) using a non-defective circuit board in advance, and the difference between the current value and the reference current change value (B) when a defective circuit board as an inspection target is used is obtained, and the difference It is a method of judging as a spark when it is not in the preset allowable range.

For example, in FIG. 5A, the change in the current value (reference current change value B) in the circuit board in which the change in the current value indicated by the broken line is a good product, and in the circuit board in which the change in the current value indicated by the solid line is defective The change in the current value is shown. FIG. 5B shows the difference between the measured current value and the reference current change value B shown in FIG. 5A, and the point A at which the difference exceeding the allowable range C is shown represents the spark occurrence point. The allowable range C in the case of using this second method is not particularly limited, but is set to ± 0.1 to 1.0 mA.

This determining means 7 is stored in advance in, for example, an AD conversion circuit (not shown) and a suitable memory (not shown) for converting the measured current value (analog value) from the circuit board to be examined into sequential digital current data. A subtraction circuit (not shown) which inputs the digital reference current change value data of the reference current change value B and the corresponding digital reference current change value data read from the digital current data and the memory and outputs the difference data; In the latter stage of the circuit, a comparison circuit (not shown) that outputs a logic height " 1 " when the difference data exceeds the digital allowable range (C) data can be configured.

In the third method, after the voltage is applied to the first inspection unit T1 by the power supply means 3, a change in the current is calculated every predetermined time, and the increase change (the slope of the change in the current is zero) from the change in the current value. Is a method of determining as a spark.

For example, in FIG. 6, the change of the current value shown by the broken line shows the change in the good circuit board, and the change in the current value shown by the solid line shows the change in the defective circuit board which is a test object. Although the change of the current value of the good product shown by the broken line walks on the right side descent, the change of the current value of the defective product shown by the solid line shows the time t1 at which the current value increases, and it shows that this point A is a spark generation point.

For example, between time t1 and time t2, the current value is reduced (negative change to current value) in the good product, but the current value increases at time t1 in the defective circuit board (the amount of change to the previous current value). It is understood that a spark has occurred. The criterion in the case of using this third method is that the change in the current value may be zero or more in order to detect the case where the current value increases, or it may be set to a specific positive change value so as to detect only a sudden change in the current value.

This determination means 7 is, for example, an AD conversion circuit (not shown) for sequentially converting the measured current value (analog value) from the circuit board to be inspected into digital current data, and the derivative for differentially processing the digital current data. The circuit (not shown) and the determination circuit or comparison circuit (not shown) for determining whether the output data of a differential circuit exceed a positive minus or predetermined value can be comprised.

Referring to FIG. 3 again, the determination means 7 is equipped with the transmission part 72 which transmits a spark detection signal, when the above-mentioned spark detection part 71 detects a spark. In the display means 8 mentioned later, this transmitter 72 may make it possible to visually detect a spark, and may recognize it visually using an alarm sound etc.

The determination means 7 is equipped with the electric power calculation part 73, and is calculating the transition of the power at the time of a spark generation from the electric current value of the 1st electric current detection means 4, and the voltage value of the voltage detection means 6. As shown in FIG. This electric power calculating part 73 may form an operation part, may set the calculation method by a user beforehand, and may set it to calculate automatically when a spark is detected.

The power calculator 73 uses, for example, a first current obtained through a suitable AD converter (not shown) using a first-in, first-out memory FIFO (not shown) having a suitable memory capacity. By sequentially accumulating the digital current data from the detection means 4 and the digital voltage data from the voltage detection means 6, and forming a means (not shown) for stopping the accumulation of these data at a predetermined time from the occurrence of sparks, Current data and voltage data for a predetermined time immediately after occurrence can be secured. By providing this electric power calculating part 73, a spark detection is carried out using the current data and voltage data of the predetermined time immediately after a spark generation, and the data of which the selection means 2 selected as the test pattern, etc. You can see the time, the pattern under test, the temporal trend of power, the size of the spark, the breakdown of insulation, and the like.

Moreover, this determination means 7 is equipped with the resistance calculation part 74, and is between the 1st test | inspection part T1 and the 2nd test | inspection part T2 from the 2nd current detection means 5 and the voltage detection means 6. The resistance value of is calculated. The resistance calculation unit 74 is, for example, a digital current value and a digital voltage by means of an appropriate AD converter (not shown) from the second current detection means 5 and the measured voltage value from the voltage detection means 6. Value, and it is possible to obtain resistance data using a division circuit (not shown).

By providing the resistance calculation part 74 and the insulation determination part 75 in this way, an insulation resistance calculation can be performed simultaneously with a spark detection test. The determination means 7 determines whether the 1st inspection part T1 and the 2nd inspection part T2 are in the insulation state. The determination means 7 can judge using a comparator (not shown) which inputs resistance value data and reference resistance value data, for example.

On the other hand, the calculation results of these power calculating sections 73, resistance calculating sections 74 and insulation determining sections 75 are sent to the transmission section 72 and displayed by the display means 8.

The display means 8 includes a first current detecting means 4, a second current detecting means 5, a voltage detecting means 6, a power calculating portion 73, a resistance calculating portion 74 and an insulation determining portion ( 75), the detected or calculated current value, voltage value, resistance value, power value, and the like can be displayed on the screen whether the presence or absence of sparks or insulation is determined, and the result of determining whether the circuit board is good or bad. In addition, this display means 8 can also display the above-mentioned numerical value and state as a graph or a table in time series. This is because by displaying in time series, the user of the insulation inspection apparatus 1 can visually confirm the occurrence state and the magnitude | size of a spark.

The above is description of the structure of embodiment of the insulation inspection apparatus 1 which concerns on this invention.

[Insulation test method]

7 is a flowchart showing an example of the inspection method of the insulation inspection apparatus according to the present invention. A computer program for executing this inspection method is stored in the storage means 10, for example, and this insulation inspection is executed under the control of the control means 9.

First, the circuit board which is a test object is provided in this insulation inspection apparatus 1, and the predetermined value for detecting a spark is set (S1). Although the above-described second method is described as an example of the spark detection method, the present invention is not limited to this method. On the other hand, in order to use the second method, the digital reference current change value data of the reference current change value B, which is the current change value by the good product, and the digital allowable range (C) data for judging good product are set in the storage means 10. .

Inspection of the target circuit board is started.

First, the selection means 2 selects a wiring pattern to be the first inspection part (inspection pattern) T1 from a plurality of wiring patterns to be inspected, and selects the remaining wiring pattern as the second inspection part T2. (S2). The first inspection unit is connected to the first and second current detection means via SW2. The patterns constituting the second inspection unit are connected to the power source means 3 via SWl, respectively. At this time, the some wiring pattern which forms the 2nd test part T2 is connected in parallel with each other.

After the wiring pattern of the circuit board is selected into two groups of the first inspection unit T1 and the second inspection unit T2, a predetermined voltage is applied to the second inspection unit T2 by the power supply unit 3 (S3). .

In this state, the first current detecting means 4, the second current detecting means 5 and the voltage detecting means 6 connected to the first inspecting section T1 are the current and voltage of the first inspecting section T1. Are respectively measured (S4). The current value and the voltage value measured by these first current detection means 4, second current detection means 5 and voltage detection means 6 are sent to the determination means 7.

The spark detection part 71 of the determination means 7 calculates the difference data based on the electric current value measured by the 1st electric current detection means 4, and a predetermined reference value (S5).

It is determined whether the difference data exists in the allowable range (C) data (S6).

When the difference data is within the allowable range (C) data, it is determined that there is no spark (no spark detection) (S7), while on the other hand, when the difference data is outside the allowable range (C) data, it is determined that a spark is detected ( S8).

If it is determined in step S8 that there is a spark, the circuit board is determined as defective (S10). In the case of spark occurrence, it is displayed on the display means 8 by the transmission part 72.

When no spark is detected, the insulation determination unit 75 performs an insulation inspection on the basis of the current value data obtained from the second current detection stage 5 and the voltage value data obtained from the voltage detection means 6. (S9). In this insulation test | inspection, the resistance calculation part 74 of the determination means 7 and the 1st test | inspection part T1 are made, using the current value and voltage value from the 2nd current detection means 5 and the voltage detection means 6. The resistance between the second inspection units T2 is calculated. In addition, in this flowchart, although the inspection process which performs an insulation inspection for every completion | finish of a spark inspection is shown, an insulation inspection may be performed before a spark inspection, and the inspection process which simultaneously performs a spark inspection and an insulation inspection may be sufficient.

The resistance value data calculated by this resistance calculation unit 74 is sent to the insulation determination unit 75. This insulation determination part 75 compares the calculated resistance value data with preset reference resistance value data, and determines the insulation state. If the calculated resistance value data is greater than or equal to the reference resistance value data, it is determined to be in an insulated state, and the circuit board is judged to be good (S11), and if the calculated resistance value data is less than the reference resistance value data, it is determined not to be in an insulated state (S12), The circuit board is determined as a defective product (S10).

When it is determined that the defective product is, it is displayed on the display means 8 by the transmitting unit 72 as in the case of spark detection.

When both the spark inspection and the insulation inspection are completed, the next first inspection portion T1 and the second inspection portion T2 are elected by the election means 2, and all the wiring patterns are inspected as the first inspection portion T1. Inspection is repeatedly performed until it is performed (S13).

On the other hand, when the content of defective goods is notified by spark generation on the display means 8, the current value data obtained from the first current detection means 4 and the voltage value data obtained from the voltage detection means 6 by the user or automatically. From the power calculation unit 73 of the determination means 7 calculates the power value data. At this time, the calculated power value data is displayed on the display means 8.

For this reason, the user of this insulation inspection apparatus 1 can immediately confirm the magnitude | size of a spark, etc. at the time of a spark occurrence. The above is description of embodiment of the insulation inspection method which concerns on this invention.

Advantages of Insulation Testing Apparatus and Insulation Testing Method According to the Present Embodiment

(1) In the conventional insulation inspection apparatus, for example, when a wiring pattern and a probe (contact pin CP) in contact with the wiring pattern are poor in connection, sparks are generated between these wiring patterns and the probe and the voltage drops. Was detected as a spark between wiring patterns in a circuit board. Moreover, also when a spark generate | occur | produced between a wiring pattern and the metal frame of this wiring pattern vicinity, it detected similarly as a spark between the wiring patterns in a circuit board. That is, there was a problem in that all the sparks generated on the circuit board were detected as sparks generated between the wiring patterns.

According to the insulation inspection apparatus and insulation inspection method of this embodiment, since a voltage is applied only to a 2nd inspection part, a potential difference arises only between a 1st inspection part and a 2nd inspection part. The current detection means connected to the first inspection unit detects only the current flowing between the first inspection unit and the second inspection unit, and detects only the spark between the wiring pattern of any one of the first inspection unit and the second inspection unit.

(2) In the conventional insulation inspection apparatus, it is impossible to detect the voltage drop accompanying a sudden change in the applied voltage, for example, on the convenience of a circuit element for forming the device. It was necessary to set the inspection time to increase long enough. As a result, this has resulted in an increase in the inspection time required to perform spark detection.

According to the insulation inspection apparatus and insulation inspection method of this embodiment, when a current value is larger than predetermined value, a spark will generate | occur | produce and it will determine that it is a defective article, and it becomes possible to determine more efficiently in a short time.

Moreover, according to the insulation inspection apparatus and insulation inspection method of this embodiment, since an insulation inspection apparatus has the 2nd current detection means which has a range different from a 1st current detection means, a spark is detected by a 1st current detection means, The leak current can be detected by the second current detecting means. For this reason, insulation inspection and spark detection inspection can be performed simultaneously, and inspection time can be further shortened.

(3) In the conventional insulation inspection apparatus, for example, in the spark detection method, the spark detection is performed only by observing the change in the voltage change and detecting the voltage drop, and it is impossible to analyze the situation and magnitude of the generated spark. It was.

According to the insulation inspection apparatus and insulation inspection method of this embodiment, since an insulation inspection apparatus has a current detection means, a voltage detection means, and a display means, the state of the change of the electric current and voltage at the time of detecting a spark is displayed by a display apparatus. In addition to this, the size (power) of the spark can be calculated and displayed. For this reason, the state of a spark can be displayed visually to a user, and it becomes possible to grasp | ascertain the state of a spark easily.

(4) Especially in recent years, the complexity of a circuit board advances and the complexity of a wiring pattern is advanced. In connection with the complexity of the wiring pattern, the area (size of the net) of the wiring pattern itself is increasing. As a result, when a voltage is applied to the wiring pattern, the wiring pattern itself accumulates electric charges, and it is easy to generate sparks. In addition, due to the miniaturization of the circuit board itself, sparks due to foreign matter inherent in the circuit board itself tend to occur.

According to the insulation inspection apparatus and the insulation inspection method of this embodiment, even if the wiring pattern is complicated and the wiring pattern itself is charged, the first current detecting means is not affected by the current, and only the current between the wiring patterns is affected. Will be measured.

And according to the insulation inspection apparatus and insulation inspection method of this embodiment, since all the wiring patterns other than the wiring pattern of the 1st inspection part are formed in parallel connection, the 2nd inspection part is sparked between 2nd inspection parts. To prevent it from happening. For this reason, it becomes possible to prevent the spark generation in wiring patterns other than a test object.

In addition, according to the insulation inspection apparatus and insulation inspection method of this embodiment, since voltage is applied only to a 2nd inspection part, a potential difference arises only between a 1st inspection part and a 2nd inspection part. For this reason, the 1st current detection means connected to a 1st inspection part detects only the electric current which flows between this 1st inspection part and a 2nd inspection part, and the spark generate | occur | produces with the wiring pattern of any one of a 1st inspection part and a 2nd inspection part. Makes it possible to detect. For this reason, even if a spark (pseudo spark) other than the wiring pattern to be inspected occurs, it can be prevented from being detected as a spark, and it is not affected even if the wiring pattern is complicated or the electric charge is generated in the wiring pattern itself. none.

Thus, the insulation inspection apparatus and insulation inspection method of this embodiment are apparatuses and methods for performing insulation inspection of a circuit board on which a plurality of wiring patterns are formed. The state of a spark can be detected correctly, and a test time can be made into a short time compared with the former.

[Alternative example]

As mentioned above, although embodiment of the insulation inspection apparatus and insulation inspection method which concern on this invention was described, this invention is not restrained by this embodiment. It should be understood that additions, deletions, modifications, and the like, which can be easily accomplished by those skilled in the art, are included in the present invention.

(1) Five types of wiring patterns are illustrated as the pattern P formed in the circuit board CB. However, wiring pattern P is not limited to these five types, The kind, number, position, size, shape, etc. of wiring pattern are not limited to the wiring pattern shown, either. The circuit board CB also targets a multilayer board in which the wiring pattern is widened into a plurality of layers via the via hole (via hole).

(2) Although each constituent circuit was illustrated in the selection means 2, the determination means 7, the storage means 10, etc. of the control means 9, it is not limited to these. Other circuits can be used that can achieve the purpose of the individual means.

(3) The pattern P formed in the circuit board CB was described as a single first inspection part (inspection pattern) and a second inspection part (all wiring patterns other than the inspection pattern) other than the first inspection part. However, an insulation inspection apparatus is an inspection performed between the to-be-tested pattern and the pattern which generate | occur | produces an insulation defect adjacent to this. In the range which can achieve this objective, "all wiring patterns other than the to-be-tested pattern" should be analyzed flexibly.

That is, although the second inspection unit is set to "all wiring patterns other than the inspection pattern", it should be understood that the present invention is the object of the present invention even if a pattern which is not likely to cause an insulation defect adjacent to the inspection pattern is excluded from the second inspection unit. . For example, when the wiring of the circuit board CB is divided into blocks, and the patterns are separated from each other and there is no fear of insulation failure, the first inspection unit and the second inspection unit are defined in a single block. .

Similarly, these patterns do not become a target of the 1st inspection part and a 2nd inspection part also in the case of insulation inspection except the pattern which does not approach the adjacent pattern.

Further, in order to depart from the technical scope of the present invention, even if some patterns are removed from the second inspection unit without any object or effect, such an embodiment is the object of the present invention.

(4) The object of the present invention also includes a computer program for causing the computer 9 to execute this insulation inspection method and a recording medium recording the same.

(5) In each inspection step, a predetermined voltage is applied from the power supply means 3 to the second inspection unit T2. Therefore, in each inspection step, a step of discharging the electric charge charged in the second inspection unit T2 may be formed.

(6) The inspection performed by the insulation inspection apparatus 1 selects the pattern P of the circuit board CB as the first inspection portion T1 and the second inspection portion T2 according to a predetermined rule, and the second The insulation inspection is performed by detecting a current flowing in the first inspection unit T1 while applying a predetermined voltage to the inspection unit T2 to generate a predetermined potential difference between the first inspection unit T1 and the second inspection unit T2. have. Here, a 1st test | inspection part consists of a single wiring pattern used as the test | inspection object selected, and the 2nd test part T2 consists of all the wiring patterns other than the 1st test part T1. The inspection is finished when each wiring pattern is sequentially selected as the first inspection unit, an insulation inspection is performed between the second inspection unit, and every wiring pattern is selected as the first inspection unit and inspected.

For this reason, in order to detect the leakage current which flows into the 1st test | inspection part T1 which consists of a single wiring pattern, in FIG. 1, FIG. 2A and FIG. 2B, between the single wiring pattern T1 and the ground (earth) point. The first current detecting means 4 and the second current detecting means 5 are connected to each other.

However, the connection point of the 1st current detection means 4 and the 2nd current detection means 5 is not limited to this. As for the leakage current which flows into the 1st test | inspection part T1 which consists of a single wiring pattern, a predetermined voltage is applied to the 2nd test | inspection part T2 from the power supply means 3, and the 1st test part T1 has insulation failure. Leakage current that occurs in the case. If there is no insulation failure in the first inspection unit T1, no current flows to the first inspection unit T1 even if a predetermined voltage is applied from the power supply means 3 to the second inspection unit T2.

Therefore, any one or both of the first current detecting means 4 and the second current detecting means 5 is connected between the power supply means 3 and the second inspecting portion T2 and flows to the second inspecting portion T2. By detecting the current, the presence or absence of insulation failure of the first inspection unit T1 can be detected. In other words, any one or both of the first current detecting means 4 and the second current detecting means 5 is the power supply means 3 and each of the second inspecting portions T2 in FIGS. 1, 2A, and 2B. You may connect between branching points. Even in this case, the current data detected by the first current detecting means 4 and the second current detecting means 5 is sent to the control means 9.

The technical scope of the present invention is determined by the description of the appended claims.

Claims (10)

An insulation inspection apparatus for inspecting insulation of a circuit board on which a plurality of wiring patterns are formed, Selecting means for selecting one wiring pattern to be an inspection object from the plurality of wiring patterns as a first inspection portion and selecting all wiring patterns to be inspection objects other than the first inspection portion as a second inspection portion; Power supply means connected to the second inspection unit and applying a voltage to the second inspection unit in order to set a predetermined potential difference between the first inspection unit and the second inspection unit; Current detecting means for detecting a current flowing between the first and second inspection units; And a judging means for comparing the current value detected by the current detecting means with a predetermined reference value and determining the circuit board as a good or defective product based on the comparison result. The method of claim 1, The said 2nd test part consists of wiring patterns other than the wiring pattern of a said 1st test part, and all these wiring patterns are connected in parallel, The insulation inspection apparatus characterized by the above-mentioned. The method of claim 1, The said current detection means is connected in series with the said 1st inspection part or the said 2nd inspection part, The insulation inspection apparatus characterized by the above-mentioned. The method of claim 1, The election means selects all the plurality of wiring patterns sequentially as the first inspection unit, The determination of the defective product is an insulation inspection apparatus that determines the defective circuit board when the current value is larger than the reference value. The method of claim 1, The current detecting means has a first current detecting means and a second current detecting means having two different ranges, The first current detecting means is formed to detect the occurrence of a spark related to the first inspection unit, The said 2nd electric current detection means is formed in order to measure the insulation resistance value between a said 1st test part and a said 2nd test part. The method of claim 5, wherein And display means for displaying the current value detected by the first current detecting means in time series. The method of claim 5, wherein The determination means has a spark detector and a power calculator, The spark detection unit detects the spark generation based on the measured current value from the first current detection means, And the power calculating unit detects the state of the spark based on the measured current value from the first current detecting unit and the measured voltage value from the voltage detecting unit detecting the voltage of the first inspecting unit. The method of claim 5, wherein The determination means has a resistance calculation unit and calculates a resistance value based on the measurement current value from the second current detection unit and the measurement voltage value from the voltage detection unit detecting the voltage of the first inspection unit. An insulation inspection method for performing insulation inspection of a circuit board on which a plurality of wiring patterns are formed, Selecting one wiring pattern to be inspected from the plurality of wiring patterns as a first inspection unit, and electing all wiring patterns to be inspected other than the first inspection unit as a second inspection unit; Applying a voltage to the second inspection unit to generate a predetermined potential difference between the first inspection unit and the second inspection unit; Detecting a current flowing between the first inspection unit and the second inspection unit while a voltage is applied to the second inspection unit; And comparing the current value flowing in the first inspection unit with a predetermined reference value, and determining the circuit board as a good or defective product based on the comparison result. In the computer which performs the insulation test of the circuit board in which the some wiring pattern is formed, Selecting one wiring pattern to be inspected from the plurality of wiring patterns as a first inspection unit, and electing all wiring patterns to be inspection other than the first inspection unit as a second inspection unit; Applying a voltage to the second inspection unit to generate a predetermined potential difference between the first inspection unit and the second inspection unit; Detecting a current flowing between the first inspection unit and the second inspection unit while a voltage is applied to the second inspection unit; And a circuit board insulation inspection method program for executing the step of judging the circuit board as a good or defective product by comparing the current value flowing in the first inspection section with a predetermined reference value.

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