JP2007322136A - Continuity inspection tool for printed wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a continuity inspection tool for a printed wiring board, which is manufactured inexpensively by facilitating manufacturing, and which is capable of constituting a wiring circuit of the printed wiring board compactly to meet high density. <P>SOLUTION: A plunger 3 is held by a plunger holding plate 12 and a plunger dropping preventive plate 13. The plunger 3 is biased by a spring 4 stored in a spring holding plate 14. A contact 10 of a contact holding plate 16 is connected to the spring 4. A conductor 11 is extended from the contact 10. The contact 10 is formed of a cut end face of the conductor 11 cut along one side face of the contact holding plate 16 after inserting the conductor 11 into a through hole 24 of the contact holding plate 16. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an inspection jig for inspecting electrical continuity of a wiring circuit of a printed wiring board.

  Conventionally, as a continuity inspection jig for inspecting a wiring circuit by measuring the continuity of the wiring circuit of the printed wiring board with a measuring instrument, one shown in Patent Document 1 is known. As shown in FIG. 4, the continuity inspection jig includes a plunger 30 that brings the tip into contact with the wiring circuit of the printed wiring board. The plunger 30 is held in a state in which the plunger 30 is prevented from dropping by the plunger holding plate 31 and the plunger drop prevention plate 32. Further, the plunger 30 is urged in the forward direction by a spring 33 formed of a conductive material, and the spring 33 is housed and held in the spring holding plate 34. Further, the spring 33 is brought into contact with the contact member 35 and is electrically conducted. The contact member 35 is held by a contact holding plate 36. The contact member 35 includes a contact portion 37 formed in a disk shape for receiving the contact of the spring 33, and a connection portion 38 extending from the center of the contact portion 37, and the connection portion 38 includes a connector sleeve. The lead wire 40 (coating stranded wire) is crimped by 39. The lead wire 40 is connected to a measuring instrument (not shown).

A large-diameter portion 41 is formed in the middle portion of the plunger 30. And the large diameter part 41 of the plunger 30 is accommodated in the accommodating part 42 formed of the plunger holding | maintenance board 31 and the plunger fall prevention board 32 so that advance / retreat is possible. Thereby, for example, when performing assembly work or maintenance work, the plunger holding plate 31 and the plunger drop prevention plate 32 hold the plunger 30 even if the spring holding plate 34 and the contact holding plate 36 are attached or removed. The state can be maintained, and an inadvertent drop of the plunger 30 can be prevented to perform an assembly operation, a maintenance operation, or the like.
Japanese Patent No. 3691368

  However, in the one disclosed in Patent Document 1, the contact member 35 includes a contact portion 37 and a connection portion 38, so that the contact holding plate 36 is in contact with the contact portion 37. Since the part accommodating part 43 and the connection part accommodating part 44 for accommodating the connection part 38 must be formed, it takes a lot of time to create the contact holding plate 36, resulting in high costs.

  When connecting the lead wire 40 to the connection portion 38 of the contact member 35, first, the lead wire 40 is penetrated through the connection portion accommodation portion 44 and the contact portion accommodation portion 43 of the contact holding plate 36, and then the lead After the tip of the wire 40 is removed and the connecting portion 38 of the contact member 35 are inserted into the connector sleeve 39 and crimped and crimped, the contact holding portion 43 and the connecting portion receiving portion 44 of the contact holding plate 36 are applied. In addition to requiring a number of processes such as housing the contact portion 37 and the connection portion 38 of the contact member 35, a plurality of parts such as the contact member 35, the connector sleeve 39, and the lead wire 40 must be handled at the same time. Low work efficiency and high cost.

  In recent years, the density of printed wiring board wiring circuits has increased, and accordingly, it has been required to inspect wiring circuits with narrower intervals. In order to inspect the wiring circuit with such a high density, it is necessary to dispose a plurality of plungers 30 at very narrow intervals.

  However, in the thing shown by the said patent document 1, even if it tries to provide the plunger 30 and the other plunger 30 close by providing the contact part 37 which the contact member 35 protrudes in disk shape, it adjoins. Since the contact members 35 come into contact with each other, there is an inconvenience that the plunger 30 and the other plunger 30 cannot be disposed close to each other.

  The present invention has been made in view of the above-described problems, and can be manufactured at low cost for easy manufacturing, and the wiring circuit of the printed wiring board can be configured compactly in response to higher density. An object is to provide an inspection jig.

  In order to achieve such an object, the present invention provides a plunger for bringing a tip into contact with a wiring circuit of a printed wiring board, a plunger holding plate for holding the plunger, and a plunger drop prevention plate for preventing the plunger from dropping from the plunger holding plate. A spring for urging the plunger in the forward direction, a spring holding plate for receiving and holding the spring, a contact for receiving the contact of the spring, a contact holding plate for holding the contact, and extending from the contact and connected to the measuring instrument The plunger is provided with a large-diameter portion having an outer diameter larger than both end sides at an intermediate portion thereof, and a plunger having a large inner diameter formed by polymerizing the plunger holding plate and the plunger drop prevention plate. In a printed wiring board inspection jig that accommodates a large-diameter portion in a freely reciprocating manner, the conductive wire is a single wire, and the contact holding plate An insertion hole through which the conducting wire is inserted, and the contact is bonded and fixed by passing the conducting wire through the insertion hole of the contact holding plate, and then the conducting wire is attached to a surface of the contact holding plate facing the spring holding plate. It is formed by the cut end surface of the conducting wire obtained by cutting along.

  According to the present invention, after the conductive wire made of a single line is inserted and bonded to the insertion hole of the contact holding plate, the conductive wire is cut along the surface of the contact holding plate facing the spring holding plate, The cut end face of the conducting wire in the same plane as the holding plate is used as a contact. Thereby, a contact can be formed without providing a contact member or a connector sleeve as in the prior art, and this can be easily performed with a reduced number of parts. In addition, since it is only necessary to form an insertion hole corresponding to the conductor without performing complicated processing on the contact holding plate, it is extremely easy to manufacture the contact holding plate, and the manufacturing cost can be reduced. Furthermore, the contact has the same outer diameter as that of the conductive wire, does not protrude in the radial direction, and the distance between both contacts can be extremely small even when another contact is provided close to the contact. Therefore, the wiring circuit can be configured compactly corresponding to the high density.

  In the present invention, it is preferable that the contact holding plate has a filling groove that is filled with an adhesive that adheres a lead to at least one inner peripheral edge of the insertion hole. According to this, before or after inserting the conducting wire into the insertion hole of the contact holding plate, by filling the filling groove with the adhesive, the adhesive is surely interposed between the insertion hole and the conducting wire through the filling groove. It can be filled, and the bonding operation can be facilitated to realize a strong bonding and fixing state of the conductive wire to the contact holding plate.

  Moreover, this invention can employ | adopt an enameled wire as a conducting wire penetrated by the penetration hole of the said contact holding plate. According to this, the contact is formed by the cut end face of the enameled wire. By adopting the enameled wire, it is cheap and easy to handle, and since polyurethane, which is generally an insulating film for the enameled wire, is easy to adhere, it can be easily and firmly fixed to the contact holding plate.

  An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory cross-sectional view showing the main configuration of the inspection jig according to the present embodiment, FIG. 2 is an explanatory view showing a contact creation operation in the present embodiment, and FIG. 3 is a usage state of the inspection jig of the present embodiment. It is explanatory drawing which shows.

  As shown in FIG. 1, the inspection jig 1 of the present embodiment includes a jig base 2, a plunger 3 that is held by the jig base 2 so as to freely advance and retract, and a spring 4 that urges the plunger 3 in the forward direction. The tip 5 of the plunger 3 is brought into pressure contact with the wiring circuit of the printed wiring board W (see FIG. 3) to conduct a continuity test between the wirings.

  The plunger 3 is formed of a conductive metal, and includes a base portion 6 connected to the spring 4 and an extending portion 7 extending outward from the jig base 2. Further, a large-diameter portion 8 having an outer diameter larger than that of the extending portion 7 or the base portion 6 is formed between the extending portion 7 and the base portion 6.

  The spring 4 is made of a metal having conductivity, and is connected in a state where one end is electrically connected to the base portion 6 of the plunger 3. Further, the other end of the spring 4 is in contact with the contact 10 via the contact member 9. As will be described in detail later, the contact 10 is formed by a cut end face of an enameled wire 11 (a conducting wire made of a single wire having a diameter of about 0.2 to 0.3 mm). The enamel wire 11 is connected to a measuring instrument (not shown). The measuring means measures electrical continuity of the wiring circuit.

  The jig base 2 is configured by laminating first to fifth plate members 12, 13, 14, 15, 16 in order from the top in FIG. The first plate member 12 (plunger holding plate) locks the first guide hole 17 that guides the extended portion 7 of the plunger 3 through the first guide hole 17 and the stepped portion of one end edge of the large-diameter portion 8 of the plunger 3. And a first locking portion 18 for preventing the removal.

  The second plate member 13 (plunger drop prevention plate) superposed on the first plate member 12 includes a second guide hole 19 that guides the base portion 6 of the plunger 3 through the other end of the large diameter portion 8 of the plunger 3. And a second locking portion 20 that locks the stepped portion of the edge to prevent it from coming off.

  Further, the first plate member 12 and the second plate member 13 are overlapped with each other so that the large-diameter portion 8 of the plunger 3 is accommodated between the first locking portion 18 and the second locking portion 20. Part 21 is formed.

  The third plate member 14 (spring holding plate) superposed on the second plate member 13 includes a spring holding portion 22 that houses the spring 4 connected to the base portion 6 of the plunger 3, and the third plate member 14. The fourth plate member 15 that has been superposed is provided with an abutting member holding portion 23 that accommodates the abutting member 9 connected to the rear end of the spring 4.

  Further, the fifth plate member 16 (contact holding plate) superposed on the fourth plate member 15 includes an insertion hole 24 for inserting and holding the enamel wire 11 in a fixed state, and an inner peripheral edge of the end portion of the insertion hole 22. And a filling groove 25 formed in this manner. The filling groove 23 is filled with an adhesive 26 a that adheres the enamel wire 11 to the insertion hole 22. A contact 10 is formed on the fourth plate member 15 by the cut end face of the enameled wire 11.

  The contact 10 is formed as follows. First, as shown in FIG. 2A, the enamel wire 11 is inserted through the insertion hole 24 of the fifth plate member 16. Next, as shown in FIG. 2B, the filling groove 25 is filled with an adhesive 26a. Alternatively, the enamel wire 11 may be inserted through the insertion hole 24 of the fifth plate member 16 after the filling groove 25 is filled with the adhesive 26a.

  As a result, the adhesive 26 a filled in the filling groove 25 enters between the insertion hole 24 and the enamel wire 11, and the enamel wire 11 is bonded and fixed inside the insertion hole 24. Here, the adhesive 26 b may be applied along the inner peripheral edge of the end of the insertion hole 24 on the opposite side of the filling groove 25. As a result, even if the adhesive 26a does not sufficiently penetrate from the filling groove 25 between the insertion hole 24 and the enameled wire 11, the adhesive 26b is also penetrated from the opposite side of the filling groove 25 to ensure adhesion. can do. At this time, for example, the adhesive 26a filling the filling groove 25 is colored red, and the adhesive 26b applied to the opposite side of the filling groove 25 is colored blue, so that the adhesive state can be easily obtained. It is advantageous to be able to confirm.

  Subsequently, as shown in FIG. 2C, the enamel wire 11 is cut along the surface of the fifth plate member 16 that faces the fourth plate member 15. Thereby, the contact 10 that forms the same surface as the fifth plate member 16 is formed.

  By providing the contact 10 formed in this way, manufacturing is easy and the number of parts can be reduced. Therefore, when inspecting a high-density printed circuit on a printed wiring board, even if the plurality of plungers 3 are provided and the contacts 10 are close to each other, the adjacent contacts 10 do not come into contact with each other. Can do.

  Further, during maintenance work such as replacing the spring 4 and the contact member 9, the plunger 3 is securely held by the first plate member 12 and the second plate member 13 even if the fifth plate member 16 is removed. In addition, since the contact 10 is integrated with the fifth plate member 16 and is easy to handle, maintenance work can be performed very easily.

  The inspection jig 1 having the above configuration includes, for example, an inspection jig 1 including a plurality of plungers 3 corresponding to the upper wiring w1 of the printed wiring board W, as schematically shown in FIG. The inspection jig 1 having a plurality of plungers 3 corresponding to the lower wiring w2 of the printed wiring board W is attached to the upper and lower inspection boards A1 and A2 via the columns B1 and B2, respectively. From each inspection jig 1, lead wires C by a plurality of enamel wires 10 connected to each plunger 3 are extended and connected to a measuring instrument (not shown) via a connector D. Then, by bringing the upper and lower inspection boards A1 and A2 close to the printed wiring board W, the plunger 3 is pressed against the wiring circuits w1 and w2 of the printed wiring board W, and a continuity inspection between the wirings is performed.

Explanatory sectional drawing which shows the principal part structure of the inspection jig of one Embodiment of this invention. Explanatory drawing which shows the contact creation work in this embodiment. Explanatory drawing which shows typically the use condition of the inspection jig of this embodiment. An explanatory sectional view showing a conventional inspection jig.

Explanation of symbols

  W ... printed wiring board, w1, w2 ... wiring circuit, 1 ... inspection jig, 3 ... plunger, 4 ... spring, 8 ... large diameter part, 10 ... contact, 11 ... enameled wire (conductive wire), 12 ... first plate Member (plunger holding plate), 13 ... second plate member (plunger fall prevention plate), 14 ... third plate member (spring holding plate), 16 ... fifth plate member (contact holding plate), 21 ... housing portion, 24 ... insertion hole, 25 ... filling groove, 26a, 26b ... adhesive.

Claims (3)

A plunger that contacts the wiring circuit of the printed wiring board, a plunger holding plate that holds the plunger, a plunger fall prevention plate that prevents the plunger from dropping from the plunger holding plate, and a spring that biases the plunger in the forward direction A spring holding plate for receiving and holding the spring, a contact for receiving the contact of the spring, a contact holding plate for holding the contact, and a lead wire extending from the contact and connected to the measuring instrument, the plunger being an intermediate part thereof Has a large-diameter portion whose outer diameter is larger than both ends, and a large-diameter portion of the plunger is accommodated in a housing portion having a large inner diameter formed by polymerizing the plunger holding plate and the plunger drop prevention plate. In the inspection jig for wiring boards,
The conducting wire consists of a single wire,
The contact holding plate includes an insertion hole through which the conducting wire is inserted,
The contact is obtained by cutting the conductive wire obtained by passing the conductive wire through the insertion hole of the contact holding plate and bonding and fixing the conductive wire along the surface of the contact holding plate facing the spring holding plate. A printed circuit board continuity inspection jig, characterized by being formed by an end face.   The printed wiring board continuity inspection jig according to claim 1, wherein the contact holding plate includes a filling groove that is filled with an adhesive that adheres the conductive wire to an inner peripheral edge of at least one end of the insertion hole.   3. The continuity inspection treatment for a printed wiring board according to claim 1, wherein the conducting wire inserted into the insertion hole of the contact holding plate is an enameled wire, and the contact is formed by a cut end surface of the enameled wire. Ingredients.

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