JP4835317B2 - Electrical inspection method for printed wiring boards - Google Patents

Description

  The present invention relates to an electrical inspection method for printed wiring boards used in various electronic devices such as personal computers, mobile communication devices, video cameras, and digital cameras.

  Conventionally, as an electrical inspection method for inspecting breaks and shorts on printed wiring boards, a dedicated inspection jig is prepared for each product with an inspection probe placed at a position corresponding to the inspection point selected from the mounting land of the product. However, a method in which this inspection probe is brought into contact with an inspection point of a product is mainly used. According to this method, one inspection can be performed in a short time, and it is very suitable for inspecting a large amount of the same product. On the other hand, the manufacturing cost of the inspection jig is high, and the manufacturing lead time is long. There is a problem that a storage place is required, which is not suitable for inspection of a small variety of products.

  Therefore, in recent years, the following method has become widespread as a method that does not require the inspection jig as described above. Hereinafter, this method will be briefly described.

  First, the printed wiring board is set in a vertical shape, and the ends of the upper side and the lower side are fixed to a fixing jig, and installed in the inspection apparatus. Next, several inspection probes installed on both sides of the printed wiring board are successively moved and brought into contact with predetermined inspection points by computer control, and inspection is performed by detecting electrical signals. As the alignment method here, the reference hole of the printed wiring board is inserted into the reference pin provided in the inspection apparatus, or the position of the alignment mark provided in the product is recognized by the camera provided in the inspection apparatus. It is done by the method. Then, pass / fail is determined from the electrical signal obtained through the inspection probe. The inspection is completed as described above.

  Since this method does not require the production of an inspection jig, it can be said that it is a very suitable method for inspecting many kinds and small quantities.

  As prior art document information related to the present invention, for example, Patent Document 1 is known.

JP-A-4-338530

  However, the above-described conventional electrical inspection method for printed wiring boards has the following problems.

  In other words, printed wiring boards used in personal computers, mobile communication devices, video cameras, digital cameras, and the like have become increasingly dense in response to demands for lightness, thinness and smallness, and the thickness has also become thinner. An ultra-thin thickness of 1 mm has been put into practical use.

  Further, as a material of the printed wiring board, a flexible type having no reinforcing material has been widespread in addition to a fiber woven or non-woven fabric made of glass fiber or organic material as a reinforcing material. In such a thin or flexible printed wiring board, it is not sufficient to fix the opposite two or four sides of the printed wiring board to a fixing jig, and bending and warping occur near the center, and inspection is performed. However, there is a problem that sufficient contact cannot be obtained even if the probe is brought into contact.

  Further, as shown in Patent Document 1, a method of applying tension to the printed wiring board through a fixing jig that fixes the end of the printed wiring board has been put into practical use. When tension is applied to the flexible type printed wiring board, the printed wiring board is stretched or the fixing portion is damaged.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an electrical inspection method for a printed wiring board in which an inspection probe that does not require an inspection jig is continuously moved and brought into contact with an inspection point. In an inspection apparatus, to provide an electrical inspection method for a printed wiring board capable of obtaining sufficient contact when a test probe is brought into contact with a thin or flexible printed wiring board without causing bending or warping. Objective.

  In order to solve the conventional problem, the present invention divides a printed wiring board into a plurality of inspection areas, and sandwiches an area including a part of the periphery of the inspection area from both sides of the printed wiring board with holding members. And holding the inspection probe in contact with both sides of the inspection area, inspecting the conductor circuit, and repeatedly inspecting the inspection area divided, and the holding member is the inspection A flat plate in which an opening is formed in a portion corresponding to a region, and the flat plate and the printed wiring board are fixed with a peelable adhesive in a portion including a part around the inspection region. This is an electrical inspection method for a printed wiring board.

  With this configuration, when fixing the printed wiring board to the electrical inspection device, not only fixing the outer peripheral end of the printed wiring board but also holding the periphery of the individual inspection areas constituting the printed wiring board with the holding member Since it is held, the vicinity of the inspection point with which the inspection probe comes into contact is held.

  As a result, since the flat state of the inspection area is secured, the printed wiring board is not bent or warped, and sufficient contact can be obtained when the inspection probe is brought into contact. In addition, it does not apply force such as mechanical pulling to the printed wiring board, but simply holds the periphery of the inspection area from both sides, which causes the printed wiring board to stretch or damage the fixed part. Does not happen.

  According to the present invention, the holding member is a flat plate in which an opening is formed in a portion corresponding to the inspection region. With this configuration, the printed wiring board is sandwiched by a portion other than the opening by the flat plate. The periphery of the inspection region corresponding to the opening is held by a flat plate, and the printed wiring board is not bent and warped, and sufficient contact can be obtained when the inspection probe is brought into contact.

  According to the present invention, the opening has substantially the same shape and the same size as the inspection area. With this configuration, the inspection area necessary for the inspection is exposed from the opening, and at the same time, the vicinity of the inspection area is flattened. Since it can be held by the face plate, the printed wiring board is not bent and warped, and sufficient contact can be obtained when the inspection probe is brought into contact.

  Further, according to the present invention, the external dimensions of the flat board are substantially the same as those of the printed wiring board. With this configuration, the external dimensions of the flat board holding the printed wiring board and the printed wiring board from both sides are substantially the same. Therefore, these three sheets need only be aligned and overlapped so that the outer circumferences coincide with each other, and can be easily aligned.

  Further, the present invention is to fix the flat plate and the printed wiring board with a peelable adhesive in a part including a part of the periphery of the inspection area. With this configuration, the flat board and the printed circuit board are printed around the inspection area. It is possible to prevent a gap from being formed between the printed wiring board and the printed wiring board to be bent and warped, and sufficient contact can be obtained when the inspection probe is brought into contact therewith.

  The present invention also fixes both ends of the opposite sides of the printed wiring board with a fixing jig. With this configuration, the printed wiring board can be operated by both the fixing of the printed wiring board and the holding around the inspection area. The plate is not bent and warped, and sufficient contact can be obtained when the inspection probe is brought into contact.

  Further, the present invention is to apply tension to the printed wiring board by fixing jigs at both ends of the opposite sides of the printed wiring board. With this configuration, the tension applied to the printed wiring board and the holding around the inspection area can be reduced. By both of these actions, the printed wiring board is not bent and warped, and sufficient contact can be obtained when the inspection probe is brought into contact therewith.

  In addition, after the inspection in one inspection region is completed, the printed wiring board and the holding member are relatively moved to inspect another inspection region. The inspection areas can be sequentially inspected without causing a switching loss.

  In addition, the printed wiring board is held by abutting the holding probe in the vicinity of the inspection point of the printed wiring board, the inspection probe is brought into contact with both sides of the printed wiring board, and the conductor circuit is inspected. With this configuration, since the vicinity of the inspection point of the printed wiring board is held by the holding probe, the printed wiring board does not bend or warp, and sufficient contact can be obtained when the inspection probe is brought into contact. Can do.

  In addition, when a plurality of inspection probes are arranged on each side of the printed wiring board and a plurality of conductor circuits are continuously inspected, inspection probes necessary for inspection are selected for each conductor circuit, and inspection unnecessary for inspection is performed. With this configuration, it is not necessary to install a holding probe in particular, and the inspection probe can be used as a holding probe and can be used efficiently.

  In addition, the part corresponding to the measurement point where the inspection probe abuts is supported by abutting the holding probe from the back surface of the printed wiring board. With this configuration, the inspection probe abuts the printed wiring board. Sufficient contact can be obtained by the support from the back side.

  In addition, the tip of the holding probe has a planar shape, and with this configuration, when the inspection probe is brought into contact with the printed wiring board, it can be supported planarly from the back surface, and sufficient contact can be obtained. Can do.

  In addition, a total of four probes, each having two tips that can be replaced with inspection probes and holding probes, are arranged on both sides of the printed wiring board, and the two inspection points at both ends of the conductor circuit to be inspected are both printed wiring boards. A first conductor circuit group located on the first surface of the printed circuit board, a second conductor circuit group both located on the second surface of the printed wiring board, and a third conductor located on different surfaces of the printed wiring board. Classify into circuit groups, and for each conductor circuit group, hold the probes for inspection on the two probes placed on the same surface side with the surface where each of the two inspection points of each conductor circuit is located, and the remaining two probes Inspection is performed after each of the probes is mounted. With this configuration, the four probes can be efficiently used as inspection probes and holding probes.

  According to the present invention, when the printed wiring board is fixed to the electrical inspection apparatus, not only the outer peripheral end of the printed wiring board is fixed, but also the surroundings of the individual inspection areas constituting the printed wiring board are held by the holding member. Therefore, it is possible to hold the vicinity of the inspection point where the inspection probe abuts, and the inspection area of the printed wiring board does not bend or warp, and is sufficient when the inspection probe abuts. Contact can be obtained. As a result, it is possible to provide a highly accurate electrical inspection method for a printed wiring board without erroneous determination.

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

(Embodiment 1)
1 and 2 are schematic views showing an electrical inspection method for a printed wiring board according to the present invention.

  Hereinafter, a first embodiment related to an electrical inspection method for a printed wiring board according to the present invention will be described with reference to FIGS.

  A printed wiring board 1 which is an inspection object used in the present invention is a collective printed wiring board constituted by a plurality of individual printed wiring boards, that is, an individual printed wiring board is arranged in two rows and three columns on one collective printed wiring board. Are arranged in such a manner that there are 6 in 2 rows and 4 columns, 24 in 3 rows and 8 columns, and so on.

  For example, individual printed wiring boards of 150 mm × 110 mm are arranged in 2 rows and 4 columns with an appropriate interval to form a collective printed wiring board of 500 mm × 330 mm. In the mounting process of soldering components such as IC chips, it is common to use individual individual printed wiring boards after dividing the assembled printed wiring board by cutting, but in the printed wiring board manufacturing process, it is efficient. In general, it is processed in the state of a collective printed wiring board for production.

  The electrical inspection detects defects such as disconnection, short circuit, and resistance value abnormality of the surface of the printed wiring board 1 and inside the conductor circuit if necessary, and individual printed wiring after the completion of all processing steps Although it is effective to perform the process in the form of a board, depending on the purpose, it is also effective to perform the process in the state of a collective printed wiring board in the middle of the processing step.

  In the case where the portion of the conductor circuit that is covered with the solder resist is used as the inspection point, the inspection is performed during the processing process after the formation of the conductor circuit and before the formation of the solder resist. In this case, the assembly printed wiring board It must be in a state. In addition, inspection is performed in the state of the collective printed wiring board in an appropriately selected processing step, and the whole or a part of the collective printed wiring board determined to be defective is not processed in the subsequent processing step. Sometimes it saves money.

  In the present invention, first, the printed wiring board 1 is divided into a plurality of inspection areas 2. As shown below, this is a work necessary for maintaining the periphery of the inspection area 2, and instead of actually cutting, a plurality of inspection areas 2 are set in advance and an electric inspection is performed for each inspection area 2. Is to do. Since the printed wiring board 1 is a collective printed wiring board constituted by a plurality of individual printed wiring boards as described above, each individual printed wiring board is generally set as the inspection region 2. When the size of the individual printed wiring board is small, a plurality of adjacent individual printed wiring boards may be combined into one inspection region 2.

  For example, in the case of a collective printed wiring board constituted by 32 individual printed wiring boards in 4 rows and 8 columns, 2 rows and 2 can be obtained by setting 8 individual printed wiring boards in 2 rows and 4 columns as one inspection region 2. Four inspection areas 2 in a row can be set. Here, the number of inspection areas 2 set differs depending on how many individual printed wiring boards are included in the inspection area 2. Although the effect of the present invention is enhanced by dividing the inspection area 2 into a large number of inspection areas 2, it takes time and labor for the work. The number of inspection regions 2 to be set may be appropriately selected in consideration of the balance between the degree of the effect intended by the present invention and labor.

  Next, as shown in FIG. 1, plane plates 3a and 3b provided with openings 4a and 4b are prepared. The openings 4a and 4b may have substantially the same shape and substantially the same size as the inspection region 2a or slightly larger than the inspection region. Then, the printed wiring board 1 is positioned and clamped from both the front and back surfaces so that the positions of the inspection region 2a and the openings 4a and 4b coincide with each other with the flat plates 3a and 3b. At this time, if the flat plates 3a and 3b have the same outer dimensions as the printed wiring board 1 and the openings 4a and 4b are processed in the same position as the inspection region 2a, the flat plates 3a and 3b are preliminarily processed. And the printed wiring board 1 can be easily aligned only by aligning the end faces.

  The printed wiring board 1 thus sandwiched between the flat plates 3a and 3b is then fixed to the inspection apparatus as shown in FIG. FIG. 2 schematically shows a main part necessary for explanation in the inspection apparatus. The printed wiring board 1 sandwiched between the flat plates 3a and 3b is set up in a vertical direction with the end surfaces thereof aligned with the flat plates 3a and 3b, and both ends of opposite sides are fixed by the fixing jig 5.

  FIG. 2 shows an example in which the upper side is fixed by the fixing jigs 5a and 5b, and the lower side opposite thereto is fixed by the fixing jigs 5c and 5d. The chucking portion of the fixing jig 5 may use a known method such as a spring type or a screw type. The number of the fixing jigs 5 is not particularly limited to the example of FIG. 2, and may be three or more on one side, or may have a wide width over the entire side. Further, the fixing location may be two sides on the left and right instead of two sides on the top and bottom, or may be fixed on all four sides.

  By fixing the printed wiring board 1 to the inspection apparatus with the configuration as described above, the portion including the periphery of the inspection region 2a of the printed wiring board 1 can be held by being sandwiched between the flat plates 3a and 3b. The inspection area 2a is secured in a flat state by a flat plate and does not bend or warp.

  Next, the inspection probes 6a and 6b installed on the front side of the printed wiring board 1 and the inspection probes 6c and 6d installed on the opposite side thereof are successively and successively controlled by computer control in a predetermined area of the inspection region 2a. The inspection is performed by moving to and contacting the inspection point and detecting an electrical signal. Then, pass / fail is determined by an electric signal obtained from the printed wiring board 1 via the inspection probe 6.

  Since no bending or warping occurs in the inspection region 2a, sufficient contact can be obtained when the inspection probe 6 is brought into contact therewith. When this operation is completed for all scheduled inspection points in the inspection area 2a, the inspection in the first inspection area 2a is completed.

  Next, in order to inspect another inspection area 2, the flat plate 3 was replaced with one having an opening 4 at a position corresponding to the other inspection area 2, and the first inspection area 2 a was performed. The inspection areas 2b to 2d are inspected by the same method as above. By repeating this over all the inspection areas 2, all inspections of the printed wiring board 1 are completed.

  In addition, it is also possible to more reliably prevent bending and warping by applying tension to the printed wiring board 1 by the fixing jig 5 that fixes the printed wiring board 1 simultaneously with the above operation.

  In addition, when the original warp of the printed wiring board 1 is large, it is generated between the flat board and the printed wiring board in the vicinity of the central portion only by fixing the flat board and the printed wiring board only at the side portions. Deflection and warpage may occur due to the gap. In order to prevent this, the flat board and the printed wiring board are fixed by a method such as applying a peelable adhesive to a portion including a part of the periphery of the inspection region 2 near the center of the flat board 3. Is also effective. The adhesive may be fluid or may be of a type in which layers of adhesive are provided on both sides of the tape. The silicone adhesive tape was good in terms of easy removal and no adhesive remaining.

  Further, as shown in the present embodiment, it is preferable to fix the printed wiring board 1 in a state in which the printed wiring board 1 stands in the vertical direction, in order to prevent bending and warping, but in the horizontal direction, the moving direction of the probe is preferable. Most of them are horizontal and move up and down against gravity. Therefore, this is preferable when reducing the load on the drive unit of the inspection apparatus.

  Furthermore, in the first embodiment, an example in which only one opening 4 is formed in one flat plate 3 is shown. However, for example, a plurality of openings corresponding to non-adjacent inspection regions 2 so as to have a staggered arrangement. 4 may be formed, or the opening 4 corresponding to the adjacent inspection region 2 may be formed if the interval between the inspection regions 2 is relatively large. By increasing the number of openings 4 formed in one flat plate 3, switching work for replacing the flat plate 3 can be reduced. What is necessary is just to select suitably, verifying the plane state of the test | inspection area | region 2 of the printed wiring board 1, and the bending | flexion and the curvature being prevented.

(Embodiment 2)
Next, as a method of holding the inspection region 2 of the printed wiring board 1, a frame-shaped member having a size slightly larger than the inspection region 2 is used as a holding member instead of the flat plate 3 in the first embodiment. The method used will be described with reference to FIG.

  The electrical inspection apparatus according to the second embodiment includes a fixing jig 5, a frame-shaped holding member 7, and an inspection probe 6. The frame-shaped holding member 7 is provided on the printed wiring board 1 with a plurality of inspection regions 2. In order to form the circuit board, a mechanism that can be moved to an arbitrary place in the printed wiring board 1 is provided. In this second embodiment, using this apparatus, only the printed wiring board 1 is directly fixed to the fixing jig 5, and the frame-shaped holding member 7 having driving units respectively installed on both surfaces of the printed wiring board 1 is used. Is held by sandwiching the printed wiring board 1 from both sides so as to surround the inspection region 2 of the printed wiring board 1. The size of the frame may be such that the opening is substantially the same shape and substantially the same as or larger than the inspection region 2. Since the circuit pattern design is different for each product of the printed wiring board 1, and the shape and size of the inspection area 2 are different, a frame having a size suitable for the size of the inspection area 2 of the product is previously provided for each product. It is only necessary to prepare and replace the frame portion at the tip of the holding member 7 at the time of inspection.

  In order to sandwich the printed wiring board 1, the shape and size of the two frames installed on both sides must be the same, and the two frames are aligned at the same position when contacting the printed wiring board 1. Must. With the configuration as described above, the printed wiring board 1 is held around the inspection area 2 by the frame-shaped holding member 7, so that the inspection area 2 is maintained in a flat state and no deflection or warpage occurs. Thereafter, the inspection probe 6 is continuously moved and brought into contact with a predetermined inspection point in the inspection region 2 by the same method as in the first embodiment, and an inspection is performed by detecting an electrical signal. When this operation is completed for all of the scheduled inspection points, the inspection in the first inspection area 2 is completed.

  Subsequently, the holding member 7 is moved to another inspection area 2 to be inspected next, and held by sandwiching the printed wiring board 1 from both sides so as to surround the inspection area 2 in the same manner as described above. . By repeating this over all the inspection areas 2, all inspections of the printed wiring board 1 are completed.

  According to the second embodiment, in order to inspect one printed wiring board 1 as in the first embodiment, it is not necessary to perform work by a person such as replacing the plane board 3 for each inspection region 2 in the middle. There is an advantage that all can be performed automatically.

  In the second embodiment, the holding member has a frame-like shape surrounding the periphery of the inspection region 2, but it is not necessary to surround the entire periphery, and the inspection region 2 has four corners or two opposite sides. The same effect can be achieved if it has a function of holding a part of the periphery of the.

(Embodiment 3)
Next, as a method of holding the printed wiring board 1, a method of holding the printed wiring board 1 by bringing the holding probe 8 into contact with the printed wiring board 1 instead of holding the periphery of the inspection region 2 with a holding member. This will be described with reference to FIG.

  The electrical inspection apparatus according to the third embodiment includes a fixing jig 5, a holding probe 8, and an inspection probe 6. Using this apparatus, the electrical inspection method according to the third embodiment is performed by clamping the periphery of the inspection region 2 with the flat plate 3 or the frame-shaped holding member 7 as in the first and second embodiments. Unlike the case of securing the planar state of 2, the holding probe 8 is brought into contact with the vicinity of the inspection point with which the inspection probe 6 comes into contact. As a result, even when the printed wiring board 1 is bent or warped near the inspection point, the holding probe 8 can be directly corrected by coming into contact with the printed wiring board 1. The surface on which the holding probe 8 abuts is effective even on the same surface as that on which the inspection probe 6 abuts, but the opposite surface corrects deflection and warpage in the vicinity of the inspection point, and at the same time the inspection probe 6 abuts. It is still effective because sometimes it can also function as a support from the back.

  As the operation of the inspection probe 6, in the same manner as in the first embodiment, the inspection probes 6 a and 6 b installed on the front side of the printed wiring board 1 are successively and continuously controlled by the computer control. Move to and contact the inspection point. At this time, the holding probe 8 may be moved continuously to the vicinity of the inspection probe 6 in conjunction with the movement of the inspection probe 6, or a predetermined point is determined by contacting the holding probe 8. Alternatively, the inspection point located within a certain distance may be left as it is, and if it deviates from the inspection point, it may be moved to another place and brought into contact again. However, it goes without saying that the holding probe 8 needs to be unobstructed when the inspection probe 6 comes into contact with the inspection point, and therefore movement for that purpose is required at a minimum.

  As shown in FIG. 4, the number of holding probes 8 is the same as the number of inspection probes 6 and holding probes 8, and the holding probes 8a are installed in the testing probes 6a. The holding probes 8b are installed in the testing probes 6b. These may be linked and move in pairs, or one on each of the front and back sides, or one on either side. What is necessary is just to select suitably by the deflection | deviation of the printed wiring board 1, the generation | occurrence | production of a curvature, and a product density.

  In the case of moving in a pair in conjunction with each other, it is more effective for the holding probe 8 to support the same portion from the back surface of the printed wiring board 1 as the portion where the inspection probe 6 contacts. Furthermore, it is desirable that the tip of the holding probe 8 has a planar shape because the planar state of the printed wiring board 1 can be secured.

  Thereafter, as in the first and second embodiments, pass / fail is determined based on electrical signals obtained from each inspection point of the printed wiring board 1 via the inspection probe 6. Since the printed wiring board 1 has been bent and warped, sufficient contact can be obtained when the inspection probe 6 is brought into contact therewith. If this operation is completed for all scheduled inspection points, the inspection is completed.

  The third embodiment is combined with the first or second embodiment, and the flat state of the inspection region 2 of the printed wiring board 1 is secured by the flat plate 3 or the frame-shaped holding member 7, and the holding probe 8 is used. A method of correcting the deflection and warpage in the inspection area 2 is also possible.

(Embodiment 4)
Further, when a plurality of conductor circuits among the plurality of inspection probes 6a, 6b and 6c, 6d arranged on both surfaces of the printed wiring board 1 are continuously inspected, the inspection probes 6 necessary for the inspection for each conductor circuit. It is also effective to use the inspection probe 6 unnecessary for inspection as a holding probe. The conductor circuit is inspected by contacting the inspection probe 6 with two inspection points on both ends of the circuit. These two inspection points may be on the same surface of the printed wiring board, but they are on opposite surfaces. In some cases. Therefore, at least two inspection probes 6 need to be arranged on both sides. Further, the number of inspection probes 6 can be increased to improve the inspection speed. However, when the number of inspection probes 6 is suppressed to the minimum number, the number of inspection probes 6 is two on both sides, for a total of four. In the fourth embodiment, of the four probes arranged on both sides, two are used as inspection probes 6 and the remaining two probes that are unnecessary for inspection are used as holding probes 6. is there.

  For example, when two inspection points are on the same surface and the inspection probes 6a and 6b are used, the opposite probes 6c and 6d are used as holding probes, and the two inspection points are on different surfaces. When the inspection probes 6a and 6c are used, the remaining probes 6b and 6d are used as holding probes. According to this method, only the minimum number of inspection probes 6 necessary for inspection can be used, and the remaining probes unnecessary for inspection can be efficiently used as holding probes for each conductor circuit.

  The contents other than the selection of the inspection probe 6 are the same as those in the third embodiment.

  Similarly to the third embodiment, the fourth embodiment is combined with the first or second embodiment, and the planar state of the inspection region 2 of the printed wiring board 1 is obtained by the flat plate 3 or the frame-shaped holding member 7. A method of securing and further correcting the deflection and warpage in the inspection region 2 with a holding probe is also possible.

(Embodiment 5)
Next, an embodiment in which the case where the inspection probe 6 and the holding probe 8 in the third embodiment are moved in pairs in conjunction with each other will be described.

  As shown in the fourth embodiment, since the number of inspection probes 6 is at least two on both sides and a total of four, a total of four holding probes 8 are required on both sides. If the inspection probe 6 and the holding probe 8 are prepared separately, a total of eight probes are required.

  Therefore, in the fifth embodiment, efficiency is improved by the following procedure.

  As the probes, a total of four probes, two on each side, which can be switched to the inspection probe 6 and the holding probe 8 by exchanging the tip are arranged in advance. The first conductor circuit group located on the first surface of the printed wiring board 1 depending on which surface of the printed wiring board 1 the two inspection points at both ends of the conductor circuit to be inspected prior to the inspection are located. And a second conductor circuit group located on the second surface of the printed wiring board 1 and a third conductor circuit group located on different surfaces of the printed wiring board 1 for each conductor circuit group. In addition, the tip of the probe is replaced as appropriate for inspection.

  When inspecting the first conductor circuit group, since both inspection points are located on the first surface of the printed wiring board 1, the inspection probe 6 is attached to the probe arranged on the first surface side correspondingly. Then, the holding probe 8 is attached to the remaining probes disposed on the second surface side. If the predetermined probe can be mounted, the inspection probe 6 is continuously moved to a predetermined inspection point by computer control and brought into contact with the predetermined inspection point. At the same time, the holding probe 8 has the same position as the position where the inspection probe 6 contacts. 1 so that it is supported from the back side. Then, pass / fail is determined by an electric signal obtained from the printed wiring board 1 via the inspection probe 6. When this operation is completed for all scheduled inspection points, the inspection of the first conductor circuit group is completed.

  Thereafter, the inspection is repeated with the second conductor circuit group and the third conductor circuit group after exchanging the tip of the probe with a predetermined probe by the same method, and all the inspections of the printed wiring board 1 are completed.

  According to this method, the minimum number of probes required for the inspection can be efficiently used and used as the inspection probe 6 and the holding probe 8.

  Needless to say, the first, second, and third circuit groups may be inspected in any order. Further, depending on the circuit arrangement of the product, the inspection of any one or two of the first, second, and third circuits may be omitted.

  As described above, the printed wiring board electrical inspection method according to the present invention includes a printed wiring board electrical inspection method and a printed wiring board in which an inspection probe that does not require an inspection jig is continuously moved and brought into contact with an inspection point. In the electrical inspection device of this type, it is possible to inspect thin or flexible printed wiring boards without causing deflection or warpage, and various electronic devices such as personal computers, mobile communication devices, video cameras, digital cameras, etc. It is useful as an electrical inspection method for printed wiring boards and an electrical inspection apparatus for printed wiring boards.

Schematic which shows the electrical inspection method of the printed wiring board of this invention Schematic which shows the electrical inspection method of the printed wiring board of this invention Schematic which shows the electrical inspection method of the printed wiring board of this invention Schematic which shows the electrical inspection method of the printed wiring board of this invention

DESCRIPTION OF SYMBOLS 1 Printed wiring board 2 Inspection area | region 3 (3a, 3b) Plane board 4 (4a, 4b) Opening part 5 (5a, 5b, 5c, 5d) Fixing jig 6 (6a, 6b, 6c, 6d) Inspection probe 7 (7a, 7b) Holding member 8 (8a, 8b) Holding probe

Claims (3)

The printed wiring board is divided into a plurality of inspection areas, the area including a part of the periphery of the inspection area is held by holding the printed wiring board from both sides with a holding member, and inspection probes are provided on both sides of the inspection area. Inspecting the conductor circuit by abutting and sequentially inspecting the inspection area divided by repeating this,
The holding member is a flat plate in which an opening is formed in a portion corresponding to the inspection region,
An electric inspection method for a printed wiring board, wherein the flat board and the printed wiring board are fixed with a peelable adhesive in a portion including a part of the periphery of the inspection area. The electrical inspection method for a printed wiring board according to claim 1, wherein both ends of opposite sides of the printed wiring board are fixed with a fixing jig. The printed wiring board electrical inspection method according to claim 2, wherein tension is applied to the printed wiring board by fixing jigs at both ends of the opposite sides of the printed wiring board.

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