TWI598604B - Printed circuit board inspection apparatus and method - Google Patents

Description

Printed substrate inspection device and inspection method

The present invention relates to an apparatus for inspecting an electrical state of a conductor pattern of a printed substrate and an inspection method thereof.

The present application claims priority based on Japanese Patent Application No. 2014-153493, filed on Jan. 29, 2014.

When inspecting the disconnection electric isoelectric state of the conductor pattern of the printed circuit board, generally, the inspection probe is brought into contact with both ends of the conductor pattern to conduct conduction inspection, but one end of the conductor pattern is insulated by the insulating film. In the case of covering, or in the case of a touch panel or the like, it is impossible to directly contact the inspection probe with the conductor pattern. In such a case, as disclosed in Patent Document 1 and Patent Document 2, the inspection probe can be inspected in a non-contact state with respect to the conductor pattern.

In the substrate inspection applied to a flexible printed circuit board or the like, the probe is brought into contact with the inspection target electrode group on one side of the conductor pattern one by one, and the non-contact sensor is brought close to the conductor pattern. The other side of the inspection target electrode group is disposed, and the non-contact sensor captures a weak electromagnetic field (or electromagnetic wave) with respect to the inspection target electrode, and determines whether or not the disconnection of each conductor pattern is good or not.

Patent Document 2 discloses that the probe is electrically connected to each of the plurality of conductor patterns on the printed substrate, so that the sensor for detecting the inspection signal is non-transparent for the plurality of conductor patterns. In the form of contact, the capacitive coupling is performed, and an electrical signal having a rapid change is sequentially input to the probe, and the conduction state of the conductor pattern is determined according to the maximum value of the transient current flowing through the sensor.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent No. 2994259

[Patent Document 2] Japanese Patent No. 3361311

However, in the method described in any of the patent documents, the probe for detecting an electric signal is disposed in a non-contact manner with respect to the conductor pattern, and since the conductor pattern is not directly contacted, there is a possibility that the signal cannot be reliably detected.

The present invention has been made in view of such a situation, and provides a printed circuit board inspection device and an inspection method capable of accurately detecting a signal by detecting a signal in which a probe for detecting an electrical signal is in direct contact with a conductor pattern, thereby enabling accurate inspection. .

The printed circuit board inspection apparatus of the present invention is characterized in that the electrical detection device for applying a signal to the conductor pattern of the printed circuit board to inspect the conductor pattern is provided with a first probe that is in contact with one end of the conductor pattern; a second probe, wherein the isolation barrier is disposed at the other end of the conductor pattern; a constant current source; the first connection device is configured to connect the first probe to the constant current source; and the second connection device is used The electrical connection state of the second probe with respect to the reference potential of the constant current source is changed, and the measuring circuit is configured to measure the potential of the first probe with respect to the reference potential of the constant current source.

Further, in the printed circuit board inspection method of the present invention, the first probe is directly in contact with one end of the conductor pattern, and the second probe dielectric barrier is disposed at the other end of the conductor pattern. At time T1, the current source current source is caused to flow to the first probe, and the second probe is electrically connected to the reference potential of the constant current source at time T2 after a predetermined time t12 elapses from time T1. The connection state is changed, and the quality of the conductor pattern is determined based on the measurement result of the potential of the first probe with respect to the reference potential of the constant current source at the time of the change.

In the printed circuit board inspection method, when the electrical connection state of the second probe with respect to the reference potential of the constant current source is changed, the potential displacement amount of one end of the conductor pattern at a specific unit time tu changes. In the case of the case, it can be determined that the conductor pattern is good.

In the present invention, the first probe is brought into contact with one end of the conductor pattern, and the second probe is disposed at the other end of the conductor pattern, and the electrical connection state of the second probe side is changed, and the first measurement is performed. The potential of the probe. In other words, since the electrical signal of the first probe in the state of being in contact with the conductor pattern is detected, the electrical signal can be reliably detected, and accurate substrate inspection can be performed.

In this case, when the insulating system disposed at the other end of the conductor pattern of the printed circuit board is exposed on the surface of the printed circuit board at the other end of the conductor pattern, the prepared person is disposed on the other end of the conductor pattern as appropriate. When the other end of the conductor pattern is covered with an insulating film, the insulating film may be an insulator, and the second probe may be disposed on the insulating film.

Further, the second connection device can change the connection state of the second probe by connecting or blocking the second probe with respect to the reference potential of the constant current source.

In addition, both the first probe and the second probe are disposed on one surface side of the printed circuit board, and are disposed on the opposite side of the printed circuit board.

In the printed circuit board inspection apparatus of the present invention, a capacitor having a specific electrostatic capacitance is connected between the second probe and the second connection device, or between the second probe and a reference potential of the constant current source. Either or both.

By the presence of a capacitor, the amount of potential displacement on the first probe side can be increased, and more can be implemented. Accurate inspection.

In the printed circuit board inspection device of the present invention, a third connection device for connecting the first probe to the reference potential of the constant current source via the first connection device may be provided.

In the method of inspecting a printed circuit board according to the present invention, the first probe may be connected to a reference potential of the constant current source at a time T3 before a predetermined time t31 from the time T1, and may be specified from the time T1. At time t14, at time T4 before time T2, the first probe and the reference potential are set to an off state.

By connecting the first probe to the reference potential and discharging the charged charge such as the wiring portion before the potential measurement, the influence of charging can be eliminated, and the current from the constant current source can be stabilized in a short time. Implement an accurate inspection.

In the printed circuit board inspection apparatus of the present invention, the conductor pattern that is in contact with the conductor pattern of the printed circuit board via the insulating plate may be connected to the reference potential of the constant current source.

It is also possible to check whether the contact state of the first probe of the conductor pattern is good or not, and it is possible to perform an accurate inspection in a state where the first probe is surely brought into contact with the conductor pattern.

In this case, the insulating plate may be prepared separately from the printed substrate. However, if the surface of the printed substrate has a portion covered with the insulating film, the insulating film may be used as an insulating plate to bring the conductive plate into contact with the insulating plate. .

According to the present invention, since the probe for detecting the electric signal is inspected to be in direct contact with the conductor pattern, the signal can be reliably detected, and an accurate inspection can be performed.

1‧‧‧Printing substrate

2‧‧‧Insulation

11‧‧‧Printed substrate inspection device

12‧‧‧Constant current source

13‧‧‧Insulator

14‧‧‧1st connection device

14'‧‧‧1st connection device

15‧‧‧2nd connection device

15'‧‧‧2nd connection device

16‧‧‧Measurement circuit

17‧‧‧Constant current source control unit

18‧‧‧Connected Device Control Department

19‧‧‧A/D conversion department

20‧‧‧ Potential Measurement Department

21‧‧‧Main control unit

22‧‧‧ display device

23‧‧‧3rd connection device

25‧‧‧Conductor board

31‧‧‧Printed substrate inspection device

41‧‧‧Printed substrate inspection device

51‧‧‧Printed substrate inspection device

61‧‧‧Printed substrate inspection device

71‧‧‧Printed substrate inspection device

81‧‧‧Printed substrate inspection device

A1~A4‧‧‧Toggle switch

B1~B4‧‧‧Toggle switch

C1~C4‧‧‧ capacitor

C5~C8‧‧‧ capacitor

E1~E4‧‧‧ conductor pattern

P1~P4‧‧‧1st probe

P5~P8‧‧‧2nd probe

S‧‧‧Toggle switch

T1‧‧‧ moments

T2‧‧‧ moments

T3‧‧‧ moments

T4‧‧‧ moments

V ₀ ‧‧‧ Potential at one end of the conductor pattern

S1~S8‧‧‧Steps

S11, S12‧‧‧ steps

S15‧‧‧ steps

Fig. 1 is a block diagram showing a schematic configuration of a first embodiment of a printed circuit board inspection device according to the present invention.

2 is a view showing a wiring shape of a printed circuit board in the printed circuit board inspection apparatus of FIG. Side view of the state.

Fig. 3 is a flow chart showing a method of inspecting a printed circuit board according to the first embodiment.

Fig. 4 is a graph showing the electrical characteristics of the potential of the first probe as a function of time when the conductor pattern is good in the first embodiment.

Fig. 5 is a graph showing the electrical characteristics of the potential of the first probe as a function of time when the conductor pattern is a defective product in the first embodiment.

Fig. 6 is another electric characteristic diagram when the conductor pattern is good in the first embodiment.

Fig. 7 is another electric characteristic diagram in the case where the conductor pattern is a defective product in the first embodiment.

Fig. 8 is a block diagram showing a schematic configuration of a second embodiment of the printed circuit board inspection device of the present invention.

Fig. 9 is a side view showing the state of wiring of the printed circuit board in the printed circuit board inspection apparatus of Fig. 8.

Fig. 10 is a block diagram showing a schematic configuration of a third embodiment of the printed circuit board inspection device of the present invention.

Fig. 11 is a side view showing the state of wiring of the printed circuit board in the printed circuit board inspection apparatus of Fig. 10.

Fig. 12 is a block diagram showing a schematic configuration of a fourth embodiment of the printed circuit board inspection device of the present invention.

Fig. 13 is a side view showing the state of wiring of the printed circuit board in the printed circuit board inspection apparatus of Fig. 12.

Fig. 14 is a flow chart showing a method of inspecting a printed circuit board in the fourth embodiment.

Fig. 15 is a graph showing the electrical characteristics of the potential of the first probe as a function of time when the conductor pattern is good in the fourth embodiment.

Figure 16 is a view showing the first case when the conductor pattern is a defective product in the fourth embodiment. An electrical characteristic diagram of the potential of the probe as a function of time.

Fig. 17 is another electric characteristic diagram in the case where the conductor pattern is good in the fourth embodiment.

Fig. 18 is another electric characteristic diagram in the case where the conductor pattern is a defective product in the fourth embodiment.

Fig. 19 is a block diagram showing a schematic configuration of a fifth embodiment of the printed circuit board inspection device of the present invention.

Fig. 20 is a side view showing the state of wiring of the printed circuit board in the printed circuit board inspection apparatus of Fig. 19.

Fig. 21 is a flow chart showing a method of inspecting a printed circuit board in the fifth embodiment.

Fig. 22 is a graph showing the electrical characteristics of the potential of the first probe as a function of time when the conductor pattern is good in the fifth embodiment.

Fig. 23 is a graph showing the electrical characteristics of the potential of the first probe as a function of time when the conductor pattern is a defective product in the fifth embodiment.

Fig. 24 is a view showing another electrical characteristic when the conductor pattern is good in the fifth embodiment.

Fig. 25 is another electric characteristic diagram in the case where the conductor pattern is a defective product in the fifth embodiment.

Fig. 26 is a view showing electrical characteristics of the case where the first probe is in poor contact with the conductor pattern in the fifth embodiment.

Fig. 27 is a view showing another electrical characteristic of the case where the first probe is in poor contact with the conductor pattern in the fifth embodiment.

Fig. 28 is a block diagram showing the configuration of a sixth embodiment of the printed circuit board inspection device of the present invention.

Fig. 29 is a side view showing the state of wiring of the printed circuit board in the printed circuit board inspection apparatus of Fig. 28.

Fig. 30 is a block diagram showing the configuration of a seventh embodiment of the printed circuit board inspection device of the present invention.

Fig. 31 is a side view showing the state of wiring of the printed circuit board in the printed circuit board inspection apparatus of Fig. 30;

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[About printed substrate]

In the printed circuit board 1 to be inspected in the following embodiments, various conductor patterns E1 to E4 are formed on the surface or inside the flat insulating layer 2. The insulating layer 2 has both a single layer and a plurality of layers. In the case where the insulating layer 2 includes a plurality of layers, the conductor patterns E1 to E4 also have a multilayer structure, and are connected between the upper and lower layers by vias or through holes. Further, both ends (electrode portions) of the respective conductor patterns E1 to E4 are provided on the surface of the insulating layer 2. In this case, both ends of the conductor patterns E1 to E4 may be provided only on one of the one surface or the other surface of the printed circuit board 1 and may be provided separately on both surfaces. Further, at least one end portion of the conductor patterns E1 to E4 is exposed on the surface of the printed circuit board 1. The other end portion may be exposed to the surface of the printed substrate 1, or may be in a state of being covered by the insulating film.

In the following embodiments, the printed circuit board 1 is formed with conductor patterns E1 to E4 on the upper surface of the insulating layer 2, and both end portions of each of the conductor patterns E1 to E4 are exposed on the surface of the insulating layer 2 of the printed circuit board 1. Shown.

[First Embodiment]

As shown in FIG. 1 and FIG. 2, the printed circuit board inspection apparatus 11 of the first embodiment inspects a plurality of conductor patterns E1 to E4 of the printed circuit board 1 including a constant current source 12 that generates a specific current; a plurality of first probes P1 to P4 directly contacting one end portion of each of the conductor patterns E1 to E4 on the printed circuit board 1 and a plurality of second ends respectively contacting the other end portions of the conductor patterns E1 to E4 via the insulator 13 Probes P5~P8; have The probes P1 to P4 are respectively connected to the first connection device 14 of the plurality of switches A1 to A4 of the constant current source 12 and have a reference potential for connecting the second probes P5 to P8 to the constant current source 12 ( a second connecting device 15 of a plurality of switching switches B1 to B4, usually a ground potential); a measuring circuit 16 for measuring the potential of the first probes P1 to P4 with respect to a reference potential of the constant current source 12; The constant current source control unit 17 of the constant current source 12; the connection device control unit 18 for controlling each of the connection devices; and the A/D (analog to digital) conversion unit 19 and the potential measurement unit connected to the measurement circuit 16 20; a main control device 21 and a display device 22 for controlling the control unit and the potential measuring unit. The main control device is provided with a CPU (Central Processing Unit), a memory, an inspection condition setting unit, an inspection determination unit, and a data communication unit with each unit.

The printed circuit board inspection apparatus 11 causes the first probes P1 to P4 to directly contact one end of the conductor patterns E1 to E4 exposed from the insulating layer 2 of the printed circuit board 1, and is disposed at the other end of the conductor patterns E1 to E4 to isolate the edge body 13 Second probe P5~P8.

As described above, when the other end portions of the conductor patterns E1 to E4 are exposed on the surface of the printed substrate 1 and covered by the insulating film, when exposed to the surface of the printed substrate 1, a suitable insulator 13 is interposed. When the second probes P5 to P8 are disposed and the other end portions of the conductor patterns E1 to E4 are covered with an insulating film, the insulating film is used as the insulator 13 referred to herein by the second probes P5 to P8. The insulating film is placed in contact with the separator 13 and placed in a state in which it is placed. In the example of the figure, the second probes P5 to P8 are disposed at the ends of the conductor patterns E1 to E4 by blocking the edge body 13.

By arranging the first probes P1 to P4 and the second probes P5 to P8 in this manner, and setting any one of the switches A1 to A4 of the first connection device 14 to be in a connected state, the current is set to a constant current. The source 12 flows to the state of any of the first probes P1 to P4. Thereby, electricity is stored in the capacitance of the wiring portion or the like of the device including any one of the conductor patterns E1 to E4, and as a result, the measurement circuit 16 connected to the state of any of the first probes P1 to P4 is measured. The potential of the first probe P1 to P4 relative to the reference potential of the constant current source 12 Bit) rises.

Then, any of the changeover switches B1, B2, B3 or B4 connected to any one of the conductor patterns (selected conductor patterns) connected to the constant current source 12 among the change switches B1 to B4 of the second connection device 15 is activated. As long as the selected conductor patterns E1 to E4 are normal, the potential measured by the measuring circuit 16 changes due to the operation of the second connecting means 15. When the selected conductor patterns E1 to E4 are broken, even if the second connecting device 15 is activated, the potential measured by the measuring circuit 16 does not change. By detecting whether or not the potential is changed, any one of the conductor patterns E1 to E4 to be inspected can be sequentially selected in such a manner, and the quality of the selected conductor patterns E1 to E4 can be identified.

The details of the inspection will be described based on the flowchart of FIG. In the following description, each step will be described by referring to the symbols of the respective steps of the flowchart.

Step S1: First, the first probes P1 to P4 are directly brought into contact with one of the conductor patterns E1 to E4. Further, the second probes P5 to P8 are disposed on the other end of the conductor patterns E1 to E4.

Step S2: After the two probes P1 to P4 and P5 to P8 are arranged, at any time T1 (see FIG. 4 and the like), any one of the switches A1 to A4 of the first connection device 14 is turned on, and the current is self-determined. The current source 12 flows to any of the first probes P1 to P4. Thereby, the electrostatic capacitance of the wiring portion connected to any one of the conductor patterns E1 to E4 of the first probe to which the current is supplied and the first probes P1 to P4 to which the current is supplied is started. During charging, the potential measured by the measuring circuit 16 rises.

Step S3: The switching switch B1 connected to the selected conductor pattern E1, E2, E3 or E4 of the switching switches B1 to B4 of the second connecting device 15 is made at time T2 after the lapse of the specific time t12 from the time T1. B2, B3 or B4 is actuated to change the connection state of any of the second probes P5 to P8 with respect to the reference potential of the constant current source 12. When the change of the connection state is in a state in which the changeover switches B1 to B4 of the second connection device 15 are in an OFF state, one of the switches is turned ON, or the switch is switched. B1~B4 are When the state is turned on, one of the states is set to the off state.

Step S4: judging whether the potential displacement amount per unit time tu of one end of the selected conductor pattern E1, E2, E3 or E4 has changed according to the measurement result of the measuring circuit 16, and determining the potential displacement amount of tu per unit time has been determined In the case of the change (in the case of (YES)), the process proceeds to S5, and when it is not determined that the potential displacement amount per unit time has changed (NO (NO)), the process proceeds to S8.

As will be explained by the electric characteristic curves of FIGS. 4 and 5, as shown in FIG. 4, the potential displacement amount (electricity) at the time T2 in the middle of the rise of the potential of one of the selected conductor patterns E1, E2, E3 or E4. When the slope of the characteristic curve changes (in the case where the potential displacement amount in FIG. 4 becomes small), the process proceeds to step S5. If the potential displacement amount does not change as shown in FIG. 5, the process proceeds to step S8. The reason why the potential displacement amount changes is the change in electrostatic capacitance with respect to the reference potential of the conductor patterns E1 to E4, and FIG. 4 shows an example in which the electrostatic capacitance is increased.

On the other hand, FIG. 5 shows a case where the potential displacement amount is not changed even if the second connecting device 15 is actuated at time T2. In this case, the process proceeds to step S8.

In addition, depending on the characteristics of the inspection target substrate 1, it is possible to select whether any of the changeover switches B1 to B4 is turned off from the disconnection or from the turn-on according to the characteristics of the substrate 1 to be inspected, and The operation method in which the change in the potential displacement amount becomes large can be performed.

Step S5: determining whether the potential of one end of the selected conductor pattern E1, E2, E3 or E4 has reached the open circuit voltage V ₀ of the constant current source 12 before the second connecting device 15 is actuated, and judges that the open circuit voltage has been reached. In the case of V ₀ (in the case of the case), the process proceeds to step S6, and when it is not determined that the open circuit voltage V ₀ has been reached (in the case of NO), the process proceeds to step S7.

In the example shown in FIGS. 4 and 5, the potential does not reach the open circuit voltage V ₀ at the time T2, but in the example shown in FIGS. 6 and 7, the potential reaches the open circuit voltage V ₀ before the time T2. In this case, the process proceeds to step S6.

Step S6: determining the potential of one end of the selected conductor pattern E1, E2, E3 or E4 Whether it has been displaced in the downward direction, and when it is determined that it has been displaced in the descending direction (in the case of the case), the process proceeds to step S7, and when it is not determined that the displacement has been made in the descending direction (in the case of no), the process proceeds to the step. S8.

In FIG. 6, before the time T2, the potential reaches the open circuit voltage V ₀ of the constant current source 12, and the potential is instantaneously decreased by the operation of the second connecting means 15 (that is, the potential of the potential shift amount is "0". The direction of the decline changes). As long as the potential drops as shown in FIG. 6, the process proceeds to step S7. When the electrostatic capacitance with respect to the reference potential of the conductor patterns E1 to E4 changes, the potential changes. Fig. 6 shows an example in which the electrostatic capacitance is increased.

On the other hand, as shown in FIG 7, even in the second connecting means 15 is actuated to open the case of the self nor the variation of the voltage V _0, the process proceeds to step S8.

Step S7: It is determined that the selected conductor pattern E1, E2, E3 or E4 is a good product.

Step S8: It is determined that the selected conductor pattern E1, E2, E3 or E4 is a defective product.

In other words, the potential displacement amount at one end of the conductor patterns E1 to E4 directly contacting the first probes P1 to P4 is disposed on the second probes P5 to P8 side of the other ends of the conductor patterns E1 to E4 due to the isolation of the edge body 13. When the operation of the second connecting device 15 is changed, the conductor patterns E1 to E4 are good, and when the potential displacement amount is not changed, it is determined as a defective product due to disconnection or the like.

In this manner, since the potential is measured on the side of the first probes P1 to P4 that are in direct contact with the conductor patterns E1 to E4, the potential displacement amount can be surely detected, and an accurate inspection can be performed.

Further, in the first embodiment described above, the following example is shown in which any one of the switching switches A1 to A4 of the first connecting device 14 is sequentially closed, and any one of the conductor patterns E1 to E4 is selected to be connected to The switch B1, B2, B3 or B4 of the selected conductive pattern E1, E2, E3 or E4 is actuated to check the conduction state of the selected conductive pattern E1, E2, E3 or E4 one by one. However, the switches A1 to A4 of all the first connecting devices can be simultaneously turned off, and then the switching switches B1 to B4 of the second connecting device 15 are sequentially operated, and the change of the potential at this time is detected by the measuring circuit 16. Thereby checking the conductive patterns E1, E2, E3 one by one Or the conduction state of E4. Alternatively, any one of the switches A1 to A4 of the first connecting device 14 may be turned off in sequence, and any one of the conductive patterns E1 to E4 may be selected, and the switching switches B1 to B4 of the second connecting device 15 may be simultaneously provided at the same time. Actuation, by detecting the change of the potential at this time by the measuring circuit 16, thereby checking the conduction state of the conductive pattern E1, E2, E3 or E4 one by one.

Further, when it is checked whether all of the conductive patterns E1 to E4 of the printed circuit board 1 are good, the switches A1 to A4 of the first connection device may be simultaneously turned off, and then the second connection device 15 may be turned on. All of the changeover switches B1 to B4 are simultaneously operated, and the change of the potential at this time is detected by the measurement circuit 16. The above is also the same in the second to fifth embodiments described below.

[Second Embodiment]

8 and 9 show a printed circuit board inspection device 31 according to the second embodiment. In the printed circuit board inspection device 31, between the second probes P5 to P8 and the respective switching switches B1 to B4 of the second connection device 15, respectively. Capacitors C1 to C4 having specific electrostatic capacitances are provided.

In the second embodiment, the other components are the same as in the first embodiment, and the same reference numerals will be given thereto, and the description thereof will be omitted. In addition, the printed circuit board inspection method of the printed circuit board inspection apparatus 31 of the second embodiment is the same as that of the first embodiment shown in FIG. 3, and the potential of the first probes P1 to P4 changes with time. Although the absolute value or the like is different, it is common to the first embodiment shown in FIGS. 4 to 7, and therefore the description thereof will be omitted. In the following embodiments, the same portions as those of the above-described embodiments are denoted by the same reference numerals, and the description will be simplified.

In the first embodiment, the potential displacement of the second connecting device 15 is changed by the electrostatic capacitance of the wiring portion itself including the floating electrostatic capacitance. However, in the second embodiment, the second probe is used. Capacitors C1 to C4 having specific electrostatic capacitances are provided between the pins P5 to P8 and the second connecting device 15, and the change in electrostatic capacitance when the second connecting device 15 is actuated can be increased, and the potential displacement amount can be increased accordingly. More accurate inspection.

[Third embodiment]

10 and FIG. 11 show a printed circuit board inspection device 41 according to the third embodiment, respectively, in the second embodiment, between the second probes P5 to P8 and the respective switching switches B1 to B4 of the second connection device 15, respectively. Capacitors C1 to C4 are provided, and in the printed circuit board inspection device 41, specific static electricity is provided between the respective switching switches B1 to B4 of the second connection device 15 and the reference potential of the constant current source 12, respectively. Capacitor capacitors C5~C8. The position where only the capacitors C5 to C8 are provided is different from that of the second embodiment, and other configurations are the same as those of the second embodiment.

Therefore, in the third embodiment, the capacitance C5 to C8 provided between the second connection device 15 and the reference potential of the constant current source 12 can increase the change in electrostatic capacitance when the second connection device 15 is activated. Increase the potential displacement and perform a more accurate inspection.

In addition, the second embodiment and the third embodiment may be combined between the second probes P5 to P8 and the respective switches S1 to B4 of the second connection device 15, and The capacitors C1 to C4 and C5 to C8 are respectively provided between the respective switching switches B1 to B4 of the connection device 15 and the reference potential of the constant current source 12.

[Fourth embodiment]

Fig. 12 and Fig. 13 show a printed circuit board inspection device 51 according to the fourth embodiment. The printed circuit board inspection device 51 is configured such that the third connection device 23 having the changeover switch S is provided between the first connection device 14 and the reference potential of the constant current source 12 with respect to the printed circuit board inspection device 11 of the first embodiment. The other configuration is the same as that in the first embodiment.

Fig. 14 is a flow chart showing a method of inspecting a printed circuit board using the printed circuit board inspection apparatus 51 of the fourth embodiment. In the flowchart, the same steps as those in the flowchart of FIG. 3 are denoted by the same reference numerals and the description is simplified, and the different steps are mainly explained.

Further, the change in potential of the first probe (one end of the conductor pattern) is shown in Figs. 15 to 18, and Figs. 15 to 18 correspond to Figs. 4 to 7 of the first embodiment.

S11: Turning on the third connecting device 23 at time T3 before t31 from time T1 status. As a result, the switch of the third connection device 23 is turned on, and the charge is released when the wiring portion of the first connection device 14 or the like is charged.

S12: The third connecting device 23 is placed in the blocking state (the switching switch S is turned off) at the time T11 after the lapse of the specific time t14 from the time T1 and at the time T4 before the time T2. Since the first connection device 14 is turned on in S2 before S12, the third connection device 23 is turned off in the S12 state, and charging is started on the first probes P1 to P4 side. As shown in FIGS. 15 to 18, the potential on the side of the first probes P1 to P4 rises.

15 and FIG. 16 show the state in which the potential of the first probes P1 to P4 rises when the second connecting device 15 is actuated. In the case shown in FIG. 15, the potential displacement amount changes at time T2, so the progress is made. Up to S5, in the case shown in Fig. 16, at time T2, the potential displacement amount does not change, so the process proceeds to S8.

17 and FIG. 18 are the cases where the potential of one of the conductor patterns E1 to E4 reaches the open circuit voltage V ₀ of the constant current source 12 immediately before the second connection device 15 is actuated, and is confirmed at time T2 as shown in FIG. When there is a drop in potential, the process proceeds to S7, and if there is no change in the potential at time T2 as shown in FIG. 18, the process proceeds to S8.

In the fourth embodiment, when the third connection device 23 is provided, even when the capacitance portion of the wiring portion or the like is charged, the third connection device 23 can be discharged to start the inspection. The potential of the first probes P1 to P4 can be measured more accurately. Further, since the third connecting device 23 connects the first connecting device 14 with the first probes P1 to P4 connected to the reference potential, and then the third connecting device 23 is blocked, the conductor pattern E1 can be removed. The value of the current from the constant current source 12 of E4 is stable for a short period of time, and a more rapid inspection can be performed.

[Modification of Fourth Embodiment]

The printed circuit board inspection device 51 of the fourth embodiment shown in FIG. 12 and FIG. 13 can be basically configured, and the second embodiment can be used as shown in FIG. 8 and FIG. Capacitors are respectively provided between the pins P5 to P8 and the respective switches B1 to B4 of the second connecting device 15 C1~C4.

Further, as in the third embodiment shown in FIGS. 10 and 11, capacitors C5 to C8 may be disposed between the respective switching switches B1 to B4 of the second connection device 15 and the reference potential of the constant current source 12.

Further, capacitors C1 to C4 and C5 to C8 of the two may be provided.

In either case, it is also possible to increase the potential displacement amount in accordance with the setting of the capacitors C1 to C4 or C5 to C8, and perform a more accurate inspection.

[Fifth Embodiment]

19 and 20 show a printed circuit board inspection device 61 according to the fifth embodiment. In the printed circuit board inspection device 61, the first probes P1 to P4 and the isolation barrier 13 which are in direct contact with one of the conductor patterns E1 to E4 of the printed circuit board 1 are disposed on the other end of the other ends of the conductor patterns E1 to E4. The probes P5 to P8 are separated from the conductor plate 25 having a reference potential connected to the constant current source 12. Further, in the example shown in FIGS. 19 and 20, the first probes P1 to P4 and the second probes P5 to P8 are disposed on one surface side of the printed circuit board 1, and the conductor plate 25 is in contact with the printed circuit board 1. The other side of the insulating layer 2 is connected to the reference potential of the constant current source 12. In this case, the conductor plate 25 is formed to be in contact with the entire thickness of the insulating layer 2 of the printed substrate 1, but it is formed so as to be at least partially shieldable from the edge layer 2 and opposed to one of the conductor patterns E1 to E4 of the inspection object. The size is fine.

When the two ends of the conductor patterns E1 to E4 are separately provided on both surfaces of the printed circuit board 1 as described in the section on "Printed substrate", the second probes P5 to P8 are disposed on the edge layer. It is on the same side as the conductor plate 25 and avoids the position of the conductor plate 25.

The flow chart when the substrate inspection is performed by the printed circuit board inspection device 61 is as shown in FIG. 21. In the first preparation for inspection, the first probes P1 to P4 are directly in contact with one of the conductor patterns E1 to E4. When the second probes P5 to P8 are disposed on the other ends of the conductor patterns E1 to E4, the conductor plates 25 are disposed on the surface of the insulating layer 2 of the printed circuit board 1 (S15), and FIG. The flow chart is the same after S2.

By arranging the conductor plate 25, when the first connection device 14 is turned on at time T1 and the current self-regulated current source 12 flows to the first probes P1 to P4 (S2), it exists in the conductor patterns E1 to E4. The electrostatic capacitance between the conductor plate 25 and the conductor plate 25 is charged, and the potential detected by the measuring circuit 16 rises. Then, at time T2, the second connection device 15 is actuated to change the connection state of the second probes P5 to P8 with respect to the reference potential of the constant current source 12.

FIG. 22 shows potentials of the first probes P1 to P4 when the second connection device 15 is activated when the electrostatic capacitance between the conductor patterns E1 to E4 and the conductive plate 25 is extremely smaller than the capacitance of the wiring portion. The change in the electrostatic capacitance between the conductor patterns E1 to E4 and the conductive plate 25 is changed by the connection state of the capacitance of the wiring portion including the conductor patterns E1 to E4, and the conductor patterns E1 to E4 are good as long as they are good. The change in electrostatic capacitance in appearance reduces the amount of potential displacement per unit of time. When the electrostatic capacitance with respect to the reference potential of the conductor patterns E1 to E4 changes, the potential displacement amount changes. Fig. 22 shows an example in which the electrostatic capacitance is increased.

When the conductor patterns E1 to E4 are defective, as shown in FIG. 23, even if the second connecting device 15 is actuated, the potential displacement amount does not change, and the state before the second connecting device 15 is actuated is maintained.

On the other hand, when the electrostatic capacitance of the wiring portion is larger than the electrostatic capacitance between the conductor patterns E1 to E4 and the conductive plate 25, or the electrostatic capacitance between the conductor patterns E1 to E4 and the conductive plate 25 and the electrostatic capacitance of the wiring portion When there is little difference between them, as shown in FIG. 24, when the second connection device 15 is activated, if the conductor patterns E1 to E4 are good, the potential of the first probes P1 to P4 is slightly lowered, and then the potential is increased. The potential displacement amount which is smaller than the potential displacement amount before the connection rises. When the electrostatic capacitance with respect to the reference potential of the conductor patterns E1 to E4 changes, the potential changes. Fig. 24 shows an example in which the electrostatic capacitance is increased.

When the conductor patterns E1 to E4 are defective, as shown in FIG. 25, even if the second connecting device 15 is actuated, the potential displacement amount does not change, and the state before the second connecting device 15 is actuated is maintained.

When the electrostatic capacitance of the wiring portion is larger than the electrostatic capacitance between the conductor patterns E1 to E4 and the conductive plate 25, or the difference between the electrostatic capacitance between the conductor patterns E1 to E4 and the conductive plate 25 and the electrostatic capacitance of the wiring portion In the case of a small amount, the potential displacement amount per time tu before the second connecting device 15 is actuated is small. Therefore, it takes time before the first probes P1 to P4 reach the open circuit voltage V ₀ , so it is not illustrated at time T2. before potential reached the case the constant current source open-circuit 12 of the voltage V ₀ of, but before the time T2, the potential reached the case the constant current source open-circuit 12 of the voltage V ₀ of the system and the case of the first embodiment and the like of the same, to the conductor pattern E1 When ~E4 is a good product, the self-opening voltage V ₀ changes, and when the self-opening voltage V _{0 does not} change, the conductor patterns E1 to E4 are defective products.

[Modification of the fifth embodiment]

In the case of the fifth embodiment shown in FIG. 19 and FIG. 20, the printed circuit board inspection device 61 shown in the drawings may be basically configured, and as shown in FIGS. 8 and 9, In the second embodiment, capacitors C1 to C4 are disposed between the second probes P5 to P8 and the respective switches S1 to B4 of the second connection device 15.

Further, as in the third embodiment shown in FIGS. 10 and 11, capacitors C5 to C8 may be disposed between the respective switching switches B1 to B4 of the second connection device 15 and the reference potential of the constant current source 12.

Further, capacitors C1 to C4 and C5 to C8 of the two may be provided.

In either case, the potential displacement amount can be increased in accordance with the setting of the capacitors C1 to C4 or C5 to C8, and a more accurate inspection can be performed.

Further, as in the fourth embodiment shown in FIGS. 12 and 13, the third connection device 23 having the changeover switch S may be provided between the first connection device 14 and the reference potential of the constant current source 12.

When the third connection device 23 is provided, even when the capacitance portions such as the conductor patterns E1 to E4 are charged, since the third connection device 23 can be discharged to start the inspection, the potential can be more accurately measured. And, again, because of the conductor pattern E1~E4 The value of the current from the constant current source 12 is stable for a short period of time, so that a more rapid inspection can be performed and a more accurate inspection can be performed.

Further, in the fifth embodiment and its modifications, it is also possible to detect whether or not the first probes P1 to P4 are surely in contact with the conductor patterns E1 to E4.

FIG. 26 is a view showing a case where the capacitors C1 to C4 are disposed between the second probes P5 to P8 and the respective switches S1 to B4 of the second connection device 15 in the fifth embodiment shown in FIG. 19 and FIG. In the case where the capacitors C5 to C8 are respectively disposed between the respective switching switches B1 to B4 of the second connection device 15 and the reference potential of the constant current source 12, the first probes P1 to P4 are provided in the device. When the contact with the conductor patterns E1 to E4 is poor, the electrostatic capacitance between the first probes P1 to P4 and the conductor patterns E1 to E4 is small in appearance, so that the potential rises sharply at time T1. The open circuit voltage V _{0 is} reached instantaneously. By detecting the rising state of the potential, the contact state of the first probes P1 to P4 can be detected.

FIG. 27 shows a case where the third connection device 23 is incorporated in the fifth embodiment. When the third connection device 23 is blocked and the first probes P1 to P4 are caused to flow a current (time T4), the first probe P1 is placed. In the case where the contact with PB is poor, the potential rises sharply as in Fig. 26, so that the rising state can be detected and the contact state of the first probes P1 to P4 can be detected.

After detecting the contact failure of the first probes P1 to P4 from the rising state of the potential, the contact position, posture, and the like of the first probes P1 to P4 may be adjusted again.

[Sixth embodiment]

Next, the printed circuit board inspection device 71 of the sixth embodiment will be described with reference to FIGS. 28 and 29.

The printed circuit board inspection device 71 of the sixth embodiment has the first connection device 14' in which the change switches A1 to A4 of the first connection device 14 in the printed circuit board inspection device 11 of the first embodiment are summarized as a single changeover switch A1. That is, the plurality of first probes P1 to P4 are connected in parallel to the changeover switch A1. By turning off the changeover switch A1, the plurality of first probes P1 to P4 are simultaneously connected, and the current self-contained current source 12 is simultaneously supplied to the plurality of first probes P1. ~P4.

Thereby, the capacitance of the wiring portion or the like of the device including the conductor patterns E1 to E4 is stored, and as a result, the potential measured by the measuring circuit 16 connected to the first probes P1 to P4 (relative to the constant current) The potential of the first probes P1 to P4 of the reference potential of the source 12 rises.

Then, the change switches B1 to B4 of the second connecting device 15 are sequentially operated. As long as the conductor patterns E1 to E4 are normal, the potential measured by the measuring circuit 16 changes due to the operation of the second connecting means 15. When the conductor patterns E1 to E4 are disconnected, even if the second connecting device 15 is activated, the potential measured by the measuring circuit 16 does not change. By detecting whether or not the potential changes, it is possible to identify the quality of the conductor patterns E1 to E4.

In the sixth embodiment, the first connection device 14' in which the changeover switches A1 to A4 of the first connection device 14 in the printed circuit board inspection device 11 of the first embodiment are summarized as a single changeover switch A1 is provided. This configuration can also be applied to the printed circuit board inspection device of the second embodiment (FIG. 8), the third embodiment (FIG. 10), the fourth embodiment (FIG. 12), and the fifth embodiment (FIG. 19). The first connecting device 14.

[Seventh embodiment]

Next, the printed circuit board inspection device 81 of the seventh embodiment will be described with reference to FIGS. 30 and 31.

The printed circuit board inspection device 81 of the seventh embodiment has the second connection device 15' in which the change switches B1 to B4 of the second connection device 15 in the printed circuit board inspection device 11 of the first embodiment are summarized as a single changeover switch B1. That is, a plurality of second probes P5 to P8 are connected in parallel to the changeover switch B1. By closing the changeover switch B1, the plurality of second probes P5 to P8 can be grounded at the same time.

According to this configuration, any one of the conductive patterns E1 to E4 is selected by sequentially closing any one of the switches A1 to A4 of the first connecting device 14, and the switching switch B1 of the second connecting device 15' is activated each time. And detecting, by the measuring circuit 16, the change of the potential at this time, borrowing This can check the conduction state of the conductive pattern E1, E2, E3 or E4.

In the seventh embodiment, the second connection device 15' in which the change switches B1 to B4 of the second connection device 15 in the printed circuit board inspection device 11 of the first embodiment are summarized as a single changeover switch B1 is provided. This configuration can also be applied to the printed circuit board inspection device of the second embodiment (FIG. 8), the third embodiment (FIG. 10), the fourth embodiment (FIG. 12), and the fifth embodiment (FIG. 19). The second connecting device 15.

Further, when the second connection device 15' having the single changeover switch B1 is applied to the printed circuit board inspection apparatus according to the second embodiment, the plurality of capacitors C1 to C4 can be placed as one capacitor on the second probe. Between P5~P8 and the second connecting device 15'. Similarly, when the second connection device 15' having the single changeover switch B1 is applied to the printed circuit board inspection apparatus according to the third embodiment, the plurality of capacitors C5 to C8 can be disposed as one capacitor in the second connection device. Between 15' and the ground.

The embodiments of the present invention have been described above, but the present invention is not limited to the embodiments, and various modifications can be made without departing from the spirit and scope of the invention.

With respect to the specific times t12, t31, t14, and tu, an optimum time to match the electrical characteristics of the printed substrate can be set, and by adjusting, the change in the potential displacement amount at one end of the conductor patterns E1 to E4 can be detected more quickly and surely. Accurate substrate inspection can be performed quickly.

Further, regarding the capacitances of the capacitors C1 to C4 and C5 to C8, the potential displacement amount at one end of the conductor patterns E1 to E4 is detected more quickly and surely by setting an optimum value in accordance with the electrical characteristics of the printed circuit board. Changes can quickly perform accurate substrate inspections.

1‧‧‧Printing substrate

2‧‧‧Insulation

11‧‧‧Printed substrate inspection device

12‧‧‧Constant current source

13‧‧‧Insulator

14‧‧‧1st connection device

15‧‧‧2nd connection device

16‧‧‧Measurement circuit

17‧‧‧Constant current source control unit

18‧‧‧Connected Device Control Department

19‧‧‧A/D conversion department

20‧‧‧ Potential Measurement Department

21‧‧‧Main control unit

22‧‧‧ display device

A1~A4‧‧‧Toggle switch

B1~B4‧‧‧Toggle switch

E1~E4‧‧‧ conductor pattern

P1~P4‧‧‧1st probe

P5~P8‧‧‧2nd probe

Claims (9)

A printed circuit board inspection device which is an electrical detection device for a printed circuit board that applies an electrical signal to a conductor pattern of a printed circuit board to inspect a conductor pattern, and includes a first probe that is in contact with the conductor pattern. a second probe, wherein the isolation barrier is disposed at the other end of the conductor pattern; a constant current source; a first connection device for connecting the first probe to the constant current source; and a second connection device And a measuring circuit for measuring the first probe of the reference potential with respect to the constant current source; and a measuring circuit for measuring the first probe with respect to a reference potential of the constant current source The potential. The printed circuit board inspection apparatus according to claim 1, wherein a capacitor having a specific electrostatic capacitance is connected between the second probe and the second connection device or between the second probe and a reference potential of the constant current source Either or both. A printed circuit board inspection device according to claim 2, further comprising: a third connection device for connecting the first probe to a reference potential of the constant current source via the first connection device. A printed circuit board inspection apparatus according to claim 1, further comprising: a third connection device for connecting the first probe to a reference potential of the constant current source via the first connection device. The printed circuit board inspection apparatus according to any one of claims 1 to 3, wherein a conductor plate that is in contact with the conductor pattern of the printed circuit board via an insulator is connected to a reference potential of the constant current source. The printed circuit board inspection apparatus according to claim 4, wherein a conductor plate that is in contact with the conductor pattern of the printed circuit board via an insulator is connected to a reference potential of the constant current source. A printed substrate inspection method characterized in that a first probe is directly in contact with a conductor At one end of the pattern, the second probe isolation barrier is disposed at the other end of the conductor pattern, and at time T1, a current self-current source is started to flow to the first probe, and a predetermined time t12 elapses from time T1. At time T2, the electrical connection state of the second probe with respect to the reference potential of the constant current source is changed, and the potential of the first probe relative to the reference potential of the constant current source is measured according to the change. As a result, it is judged whether or not the above conductor pattern is good or not. The printed circuit board inspection method according to claim 7, wherein when the electrical connection state of the second probe with respect to the reference potential of the constant current source is changed, the potential of one end of the conductor pattern at each specific unit time tu When the displacement amount changes, it is determined that the conductor pattern is a good product. The method of inspecting a printed circuit board according to claim 7 or 8, wherein the first probe is connected to a reference potential of the constant current source at a time T3 before a predetermined time t31 from the time T1, and passes through the time T1. At a time t14 shorter than the time t12 and at a time T4 before the time T2, the first probe and the reference potential are set to an off state.