JPH0575667U - Test jig for in-circuit tester - Google Patents

Abstract

(57) [Abstract] [Purpose] Fix the printed wiring board in an in-circuit tester that measures the amount of electricity between each terminal connection point of the printed wiring board on which the component is soldered and inspects for erroneous mounting and component failure. An object of the present invention is to provide a test jig for in-circuit tester in which a probe pin is used as a stylus, and which is capable of providing stable stylus conduction to a printed wiring board even without flux cleaning. [Structure] At least the stylus portion of the probe pin 1 is configured to be brought into conduction with the stylus by applying a predetermined pressure in a heating state lower than the solder melting temperature and higher than the melting temperature of the flux. The heater 4 is arranged in the standing space 31 to keep it heated to a predetermined temperature and the base 3
The space between the space 31 and the probe pin 1 is composed of a sleeve 2 penetrating in the inner side of the sleeve 2 and a contact pin 5 slidably projected by a compression spring 21 inserted into the other end of the sleeve 2 and having a predetermined pressing force. Is evacuated and is fixed by suction to the printed wiring board 9 with a predetermined pressure.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention measures the amount of electricity between each terminal connection point of a printed wiring board on which components are mounted by soldering, and fixes the printed wiring board in an in-circuit tester that inspects for wiring defects, erroneous mounting, and component defects. The present invention relates to a test jig for in-circuit testers that uses a probe pin as a stylus.

Parts are mounted on a printed wiring board by soldering. Moreover, there is a step of cleaning flux and residue in the post-soldering step, and an organic halogen-based solvent (chlorofluorocarbon, trichloroethane) with a high cleaning power is generally used as the cleaning liquid.

However, the use of organic halogen-based solvents has been banned by the Montreal Agreement by the year 2000, and it is prohibited to use it. It is being strongly promoted and some are in the trial stage.

Therefore, it is required that the in-circuit tester can be used even when the flux is not cleaned.

[0005]

[Prior Art]

 FIG. 3 shows a conventional test jig for an in-circuit tester, in which (a) is a configuration diagram and (b) is an enlarged cross-sectional view of a stylus portion.

As shown in FIGS. 3 (a) and 3 (b), a probe pin 19 is provided at a predetermined position, and a printed wiring board 9 is mounted on the peripheral portion with the half-mounting surface facing downward. The base 39 is the main component, and the wiring 89 is connected to the connection terminal 24 at the exposed external end of the probe pin 19 that is provided through the wiring, and is wired to the input terminal of the tester 88.

When the printed wiring board 9 is placed on the base 39, it is placed at a fixed position by the guide pin, aligned with the probe pin 19, and further pressed against the peripheral edge to exhaust the space inside the base 39. It is airtightly connected to the decompression device 87 to evacuate and decompress, and suction-adhered and fixed.

The probe pin 19 includes a sleeve 29, a compression spring 21, and a contact pin 59. One end of the sleeve 29 is crushed and sealed to form a connection terminal 24 for the wiring 89. The spring 21 is inserted, and further, the end of the contact pin 59 is slidably loosely fitted. Since one end of the contact pin 59 touches the soldered part of the printed wiring board 9, the blade is radially crowned. The crown 52 is provided, the other end is a sliding part 53, and the middle part has a small diameter so that a retaining collar part at the tip of the sleeve 29 is hooked.

Therefore, the probe pin 19 exposes the connection terminal 24 of the sleeve 29 to the base 39 and airtightly penetrates the base pin 39, and the crown 52 of the contact pin 59 is predetermined from the peripheral surface of the base 39 on which the printed wiring board 9 is mounted. When the printed wiring board 9 is tightly fixed, the crown 52 feels and the contact pin 59 is pushed down, and the predetermined pressing force due to the elasticity of the compression spring 21 is applied to the crown 52. By cleaning, the insulating flux layer that was still attached is pierced to establish continuity with the solder layer.

Of course, all the probe pins 19 are pressed against the printed wiring board 9 at the same time, so that the printed wiring board 9 is fixed by suction so as not to move.

[0011]

[Problems to be solved by the device]

 However, the contact conduction of the soldered portion of the printed wiring board 9 is affected by the pressing force of the crown 52 to be touched and the number of times of use. In this case, the flux peeled off by the blade of the crown 52 collects and adheres to the blade, resulting in poor contact. Every time this contact failure occurs, the crown 52 must be heated to the melting temperature of the flux and wiped off, which requires manpower and man-hours. If the pressing force is large, the destructive force of the flux is also large and the number of times of use can be extended. However, since the printed wiring board 9 is mounted more and more densely, the density of the probe pins 19 is increased and the number tends to increase. Yes, the pressing force increases by that amount, and the strength of the printed wiring board 9 and the tight fixing mechanism need to be strengthened, but in reality it is unavoidable, and it is impossible to increase the pressing force of the crown 52, rather. However, the present situation is that reduction is required. There are problems such as.

In view of the above problems, it is an object of the present invention to provide a test jig for an in-circuit tester that can be stably connected to a printed wiring board by stylus even without flux cleaning.

[0013]

[Means for Solving the Problems]

 The above-mentioned purpose is, as shown in FIGS. 1 and 2, an in-circuit for measuring the amount of electricity between each terminal connection point of the printed wiring board 9 on which the component 8 is mounted by soldering and inspecting for incorrect wiring, incorrect mounting, and defective components. A test jig 91 for fixing the printed wiring board 9 and stylusing the probe pin 1 in the tester, in which at least the stylus part of the probe pin 1 is in a heating state lower than the solder melting temperature and higher than the flux melting temperature. Is achieved by the test jig 91 for the insert tester of the present invention, in which a predetermined pressure is applied to bring the stylus into conduction. [1] The above heating state is maintained at a predetermined temperature by disposing the heater 4 in the space 31 in which the lower probe pin 1 of the printed wiring board 9 is erected, and the above predetermined pressing stylus is used. A sleeve 2 having one end sealed and fixed in a corresponding position of the base 3, a compression spring 21 inserted into the sleeve 2, and a predetermined pressing force applied to the other end of the sleeve 2 by the compression spring 21. A first probe for an in-circuit tester according to the present invention, in which the space 31 is exhausted by a probe pin 1 composed of a contact pin 5 slidably projecting and the printed wiring board 9 fixed by suction is touched. This is achieved by the test jig 91. [2] Further, in the above heating state, a sleeve 22 having one end sealed and fixed in a corresponding position of the hollow base 33 and having a vent hole 23 in a side wall, and a compression spring 21 inserted into the sleeve 22, The probe pin 11 is composed of a contact pin 55, which is slidably projected by the compression spring 21 on the other end of the sleeve 22 with a predetermined pushing force, and has a vent hole 51 in the shaft center, and a hollow base 33. The compressed air of a predetermined temperature is supplied to the portion 32, and the probe pins 11 jet it to the stylus to heat it, and the predetermined pressing stylus is mounted on the peripheral edge of the base 33 by the probe pin 11. It can also be applied by the second test jig 92 for an in-circuit tester of the present invention in which the printed wiring board 9 placed is touched. [3] The flux attached to the stylus portions of the contact pins 5 and 55 of the first and second test jigs 91 and 92 is heated to rotate the cloth-coated roller 6 to rotate. It is also achieved by the first and second in-circuit tester test jigs 91 and 92 of the present invention, which are configured to have a wiping means.

[0014]

[Action]

 That is, since the stylus part between the printed wiring board 9 and the probe pins 1 and 11 is heated to a temperature at which the solder is not melted but the flux is melted, the surface flux is melted, and the stylus lowers the temperature. Since it is transferred to the part and removed, good contact can be obtained with a small pushing force, and stable conduction can be achieved every time.

In the first test jig 91, the heating heater 4 disposed in the space 31 in which the probe pin 1 is erected heats the probe pin 1 and the printed wiring board 9 for this heating. At this time, the heater 4 is preferably a local heating type for each probe pin 1, and an electric heating type whose temperature control is easy and equipment is simple is convenient.

In the second test jig 92, if compressed air of a predetermined heating temperature is supplied to the hollow portion of the base portion 33 from the outside, the vent pin 23 of the sleeve 22 of the probe pin 11 passes through the axial center of the contact pin 55. It passes through the pores 51 and is ejected from the stylus part at the tip, locally heats the stylus part surface of the printed wiring board 9 to melt the flux, and also has the effect of expelling the melting flux by the jet of compressed air. The contact with the stylus is stably obtained.

Further, in any of the probe pins 1 and 11, the compression spring 21 in the sleeves 2 and 22 presses the contact pins 5 and 55, so that a predetermined pressing force can be applied to the stylus portion.

Further, the stylus portion of all the probe pins 1 and 11 can be sequentially wiped by means of moving the roller 6 with cloth while rotating it, and since it is performed in a heated state, dust or melted adhered matter is melted. The flux is wiped off securely.

Thus, according to the present invention, it is possible to provide a test jig for an in-circuit tester which can be stably conducted to the printed wiring board by stylus even if the flux is not washed.

[0020]

【Example】

 Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. Throughout the drawings, the same reference numerals indicate the same objects. FIG. 1 shows an embodiment of the first test jig of the present invention. (A) is a configuration diagram, (b) is an enlarged sectional view of the stylus part, (c) is a side view of the stylus part in a wiped state, 2A and 2B show an embodiment of a second test jig of the present invention, wherein FIG. 2A is a configuration diagram and FIG. 2B is an enlarged cross-sectional view of a stylus portion.

In each of the examples, a circuit is configured by mounting components on a 1.6 mm-thick multilayer printed wiring board of a glass epoxy base material, which is installed in parallel on a shelf of a rack case and mounted by plug-in. It is applied to the package, the printed wiring board has an outer shape of 30 × 35 cm, the mounting grid is 2.54 mm pitch and partially uses 1.27 mm pitch, and the average number of test points is about 2000. Maximum is 3000 or less.

One embodiment of the first test jig 91 is, as shown in FIGS. 1 (a) and 1 (b), a printed wiring board 9 on which a component 8 is soldered and mounted, with its soldering surface facing downward. When mounted, it is a test jig 91 in which the probe pin 1 is touched from below to the terminal connecting portion which is a test point, and the probe pin 1 is connected to the input terminal of the tester 88 by the wiring 89.

The test jig 91 comprises a base 3 made of a glass epoxy substrate, a probe pin 1 penetrating at a predetermined position of the base 3, the base 3 fixed to the lower surface of the peripheral edge, and a printed wiring board 9 mounted on the upper surface. And a metal frame 93 that

The probe pin 1 includes a metal sleeve 2, a coil-shaped compression spring 21 to be inserted, and a contact pin 5 slidably loosely fitted to the end of the sleeve 2. One end is crushed and sealed to form the connection terminal 24 of the wiring 89, the compression spring 21 is inserted inside, and the end of the contact pin 5 is slidably loosely fitted. Has a crown 52 for touching the soldered portion of the printed wiring board 9 at one end, and a sliding portion 53 at the other end, and a small diameter is provided between them to fit a collar for preventing the tip of the sleeve 2 from coming off. Is done.

In this probe pin 1, the connection terminal 24 of the sleeve 2 is exposed and press-fitted and airtightly provided at a position corresponding to the mounting grid of the base 3. The base 3 is airtightly adhered and fixed to the periphery of the metal frame 93 via a rubber gasket. At this time, the crown 52 of the contact pin 5 is fixed from the opposite peripheral surface of the metal frame 93 so as to travel a predetermined distance.

A heating heater 4 is provided on the base 3 for each probe pin 1 by entwining a series of insulated heating wires around the sleeve 2, and the heater 4 is always energized and the printed wiring board 9 is placed thereon. The surface of the stylus is heated to about 80 ° C or higher in about 20 seconds to melt the flux.

On the opposite surface of the peripheral edge of the metal frame 93, a guide pin is provided upright at a reference position (not shown) so that the printed wiring board 9 is accurately aligned with the probe pin 1 and a similar guide is provided. The exhaust pipe 95 is airtightly provided on the side surface of the metal frame 93, and is connected to the pipe via the external exhaust pressure reducing device 87 and the switching cock 86. I am doing it.

The printed wiring board 9 is placed on the peripheral edge of the metal frame 93, pressed and brought into intimate contact, the switching cock 86 is communicated with the exhaust pressure reducing device 87, and the space 31 in which the probe pin 1 is erected is exhausted and suction fixed. For example, the probe pin 1 touches the predetermined position and the crown 52 presses the predetermined position. At the same time, the stylus portion is also heated by the heater 4 which is always in a heating state, and the flux melts and flows away from the surface, so that stable contact conduction can be obtained even with a small pressing force. In order to prevent the printed wiring board 9 from warping during the suction and increasing the pressing force of the stylus portion, support pillows are arranged on the base portion 3 at a predetermined density.

In that state, the tester 88 inspects, and when the inspection is completed, the switching cock is switched from exhaust to indoor ventilation, the suction is instantly released, and the printed wiring board 9 is removed. In addition to this, as shown in FIG. 1 (c), dust and flux accumulated on the crown 52 of the contact portion of the contact pin 5 are periodically removed to improve the contact reliability and improve the in-circuit tester. Since the operating rate can be increased, this automatic wiping means was added to the device.

The automatic wiping means is composed of a roller 6 with a cloth, a protective plate 61 and a movable mechanism portion 62. The roller 6 with a cloth is a rubber roller of 5φ × 30 cm in which a cleaning cloth is replaceably wound, and is protected. The plate 61 is a 30 × 35 cm steel plate with a thickness of 1.6 mm, and has a guide pin insertion hole and a tapered hole at the corresponding position of each probe pin 1 for the tip of the crown 52 to project approximately 1 mm and to be loosely inserted. Although not shown, the movable mechanism portion 62 is a link mechanism for moving the roller 6 with cloth and the protective plate 61, and an air cylinder as a drive source.

When the test of the printed wiring board 9 by the in-circuit tester is completed 20 times, the heating heater 4 stops the test in the heating state, the movable mechanism portion 63 operates, and the protective plate 61 is carried and the metal plate is carried. A guide pin is inserted and placed on the mounting surface of the frame 93, and then the roller 6 with cloth is rotationally moved on the upper surface of the protective plate 61 and reciprocates back and forth from end to end. The formed crown 52 is wiped with a cloth, and dust and molten flux are wiped off. Finally, the protective plate 61 is removed and stored, and the wiping action ends. Then, the printed wiring board 9 is placed again, and the test is performed. These are automatically performed by the control program of the in-circuit tester.

Next, one embodiment of the second test jig 92 is as shown in FIGS. 2A and 2B. Compared with the above embodiment, the heating mechanism of the stylus and the printed wiring board 9 are different. The fixing mechanism of is different. The heating mechanism is composed of a glass epoxy substrate having a hollow portion 32 having a hollow inside, a base portion 33 provided with an air supply pipe 34 communicating with the hollow portion 32 on the side surface portion, and a probe pin 11 which is press-fitted into the base portion 33 and penetrates hermetically. It consists of and.

Here, the probe pin 11 is composed of a sleeve 22 that is press-fitted and penetrated, a compression spring 21, and a contact pin 55. The sleeve 22 forms a connection terminal 24 that is crushed and sealed at one end, and at the press-fitting portion. A ventilation hole 23 is formed in the side surface of the hollow portion 32 at a corresponding position.

The contact pin 55 has a sliding portion 53 at one end that is slidably loosely fitted to the sleeve 22, and has a crown 52 at the other end that protrudes and comes into pressure contact. A collar for preventing slipping out of the tip of is fitted and a vent hole 51 is opened through the shaft center.

The air supply pipe 34 of the base 33 is connected to a hot air source 85 having a predetermined temperature via a cock. Therefore, if hot air is ventilated through this, the air will be ejected from the hollow portion 32 → the air vent hole 23 of the sleeve 22 of the probe pin 11 → the air vent hole 51 of the contact pin 55 → the stylus portion of the crown 52 and the surface of the printed wiring board 9. Is heated, the flux is melted, and at the same time, it is removed by the jet flow.

Since the fixing mechanism of the printed wiring board 9 cannot be fixed by suction to the metal frame 93, the fixing frame 96 is overlaid on the upper surface of the printed wiring board 9 and fixed by applying a pressing force. If removed, the printed wiring board 9 can be taken out.

The fixed frame 96 is placed on the periphery of the printed wiring board 9 placed on the metal frame 93 to apply a pressing force, and when the printed wiring board 9 is further pressed by the probe pin 11 to cause a warp. Since the specified pressing force cannot be obtained, the support pillows are arranged at a specified density so that they will not warp.

In addition, although not described, a function of wiping the crown 52 with the cloth-attached roller 6 is provided like the test jig 91. Each of the above-described embodiments is an example, and the mechanism, shape, size, and material of each part are not limited to those described above.

Although the base portion is composed of the base portions 3 and 33 and the metal frame 93, the base portion may be integrally molded with an insulating material, or the metal material may be integrally molded and the probe bushes of the probe pins 1 and 11 may be insulated and mounted. Absent.

The heating heater 4 is also provided with a tubular heating heater for each probe pin 1, is connected to the printed wiring of the base 3, and is energized.

[0041]

[Effect of the device]

 As described above, the test jig for an in-circuit tester of the present invention provides a test jig for an in-circuit tester that is highly reliable even without flux cleaning and has stable contact with the printed wiring board by stylus. The in-circuit tester operation rate is increased without using a system solvent, the flux cleaning process can be omitted, the manual wiping work can be omitted, and the pressing force of the probe pin can be reduced by 30% or more compared to the conventional example. It is possible, and it is possible to cope with high-density mounting in the future, and the effect obtained is remarkable.

[Brief description of drawings]

1 is an embodiment of the first test jig of the present invention (a) configuration diagram (b) enlarged cross-sectional view of the stylus portion (c) side view of the stylus wiped state

[FIG. 2] One embodiment of the second test jig of the present invention (a) Configuration diagram (b) Enlarged sectional view of stylus part

FIG. 3 is a conventional example of an in-circuit tester test jig (a) configuration diagram (b) enlarged cross-sectional view of the stylus part

[Explanation of symbols]

1,11,19 Probe pin 2,22,29 Sleeve 3,
33,39 Base 4 Heater 5,55,59 Coitact pin 6
Roller with cloth 8 Parts 9 Printed wiring board 21
Compression spring 23,51 Vent 24 Connection terminal 31
Space 32 Hollow part 34 Air pipe 52
Crown 53 Sliding part 61 Protective plate 62
Working mechanism 85 Hot air source 86 Switching cock 87
Exhaust pressure reducer 88 Tester 89 Wiring 9
1,92 Test jig 93 Metal frame 95 Exhaust pipe 96
Fixed frame

Claims (4)

[Scope of utility model registration request] 1. A method for measuring a quantity of electricity between terminal connection points of a printed wiring board on which a component is mounted by soldering, and erroneous wiring, erroneous mounting,
A test jig for fixing a printed wiring board and stylus of a probe pin in an in-circuit tester for inspecting component defects, in which at least the stylus part of the probe pin (1) is lower than the solder melting temperature and the melting temperature of the flux. In the above heating state,
A test jig for an in-circuit tester, characterized in that a predetermined pressure is applied to the stylus to make it conductive. 2. The heating condition according to claim 1, wherein the heater (4) is arranged in a space (31) in which the lower probe pin (1) of the printed wiring board (9) is erected up to a predetermined temperature. A sleeve (2) having one end sealed and penetratingly fixed to a corresponding position of the base (3), and a compression needle inserted into the sleeve (2). Spring (21), the compression spring (2
The space (31) is evacuated by a probe pin (1) consisting of a contact pin (5) slidably protruding with a predetermined pushing force at the other end of the sleeve (2) by the (1). A test jig for an in-circuit tester, characterized in that the printed wiring board (9) that has been suction-fixed is then touched. 3. A hollow base portion, which has the heating state according to claim 1,
One end is sealed at the position corresponding to (33), and it is fixed through and fixed to the side wall with a ventilation hole.
Sleeve (22) having (23), compression spring (21) inserted in the sleeve (22), and the sleeve by the compression spring (21)
On the other end of (22), a probe pin (11) consisting of a contact pin (55) provided slidably with a predetermined pushing force and provided with a vent hole (51) in the axial center, By supplying compressed air of a predetermined temperature to the hollow portion (32) of the base portion (33), jetting from each probe pin (11) to the stylus portion to heat, and the predetermined pressing stylus according to claim 1, A test jig for an in-circuit tester, characterized in that the probe pin (11) touches a printed wiring board (9) fixed to the opening surface of the base portion (33). 4. A means for wiping off the flux attached to the stylus portion of the contact pin (5, 55) according to claim 2 or claim 3 by rotating the roller with cloth (6) in a heated state. The test jig for an in-circuit tester according to claim 2, wherein the test jig is provided.