JPH095392A - Jig for inspecting circuit board - Google Patents

Abstract

PURPOSE: To obtain a jig for inspecting a circuit board with minimized poor contact suitable for automation of an inspecting instrument by using a push having an inverted cone-shaped bearing hole, a centripetal body or the like having a tapered part expanding upward. CONSTITUTION: A centripetal body 5 supports a probe 9 to be mounted on an IC socket actually mounted on a circuit board to be inspected and a push 2 supports the centripetal body 5 with a mobile range limited. The centripetal body 5 is made up of a horizontal vibration oscillating means 4, a centripetal shaft 13 and a link member 20. The push 2 is provided with an inverted cone- shaped bearing hole 1 and a tapered part 3 is formed on the centripetal body 5 energized downward so that the centripetal body 5 points right downward from the center of the bearing hole 1 in a steady state. As a result, the direction of the probe 9 is fixed according to a relationship of a cam groove 6 and a cam follower 7. A fine deviation is corrected in the mounting of the probe 9 on the socket by generating vibration by the horizontal vibration generating means 4 while foreign matters or the like of a pin terminal are removed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jig for inspecting a circuit board through electrical connection between each pin terminal of a socket mounted on a board to be inspected and an inspection circuit of a circuit board inspection apparatus.

[0002]

2. Description of the Related Art A burn-in board is one of the inspection boards for semiconductor chips. In order to inspect as many chips as possible on a single board, several tens of IC sockets of hundreds or more of the same standard are arranged vertically and horizontally. It is implemented. From the aspect of inspection using a burn-in board, each I
The elements connected to each pin of the C socket are all the same, and the circuit structure is also very simple. However, the shipping inspection of the burn-in board requires the circuit connected to all the pins of the IC socket mounted on the burn-in board. It had to be checked, and it was extremely complicated, and most of the manufacturing period was devoted to the shipping inspection. Moreover, today, semiconductor chips (LSIs) having hundreds of pins continue to be present, and it is impossible to process them by manual inspection. Thus, such an inspection has come to be performed by an inspection device using a computer as disclosed in, for example, Japanese Patent Laid-Open No. 5-346447, whereby the inspection time is shortened significantly.

[0003]

However, in the conventional inspection apparatus, since the person connects the IC socket and the probe to each other, the contact state becomes non-uniform due to the shaking of the hand during the inspection, and the adhesion to the pin terminals occurs. Due to the presence of the oxide film, the error frequency due to poor contact is extremely high, and the probe or the pin of the IC socket may be deformed when the force of the operator holding the probe is too strong. In addition, the introduction of an automatic inspection device that employs automatic probe insertion has led to the insertion of the probe into the IC socket with a uniform force. I haven't arrived.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a jig for inspecting a circuit board, which is suitable for automating an inspection apparatus and which has few contact defects.

[0005]

A jig for inspecting a circuit board according to the present invention, which solves the above problems, comprises a bush having a mortar-shaped bearing hole which is fixed to a movable base of an automatic insertion device and vertically penetrates the bearing base, and a bearing hole. It is composed of a centripetal body with an upwardly expanding taper part fitted with a horizontal vibration generating means. One of the cam groove and the cam follower that slides along the cam groove to limit the rotation in the same direction is provided on the centripetal body and the other is provided on the bush, and the contact terminal is located at the tip of the centripetal body. A probe which is arranged in the same manner as the above and electrically connects each contact terminal to the circuit board inspection circuit is detachably supported. The centripetal body cannot detach a horizontal vibration generating means formed by fixing an eccentric weight to a rotating shaft of a motor and a centripetal shaft having an upwardly wide tapered portion fitted in a bearing hole of the bush through a bearing. And may be coaxially connected, or horizontal vibration generating means may be used that vibrates at a non-resonant frequency with respect to the natural vibration of the centripetal body urged downward.

[0006]

[Operation] By forming a mortar-shaped bearing hole in the bush and forming a taper portion in the centripetal body urged downward,
In a steady state, the centripetal always points directly below the center of the bearing hole, and the orientation of the probe is almost fixed by the relationship between the cam groove and the cam follower. Also, by generating horizontal vibration, fine displacement when mounting the probe in the socket is corrected, and foreign matter and oxide film on the pin terminal surface of the socket are removed and fixed to the movable base of the automatic insertion device. The vibration of the automatic insertion device itself is reduced by causing the centripetal body, which is almost free from the bush, to self-oscillate. Further, as the vibration frequency of the horizontal vibration generating means, a non-resonant frequency with respect to the natural vibration of the centripetal body biased downward is selected to stabilize the vibration of the centripetal body.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of a jig for inspecting a circuit board according to the present invention will be described in detail below with reference to the drawings. In this embodiment, a centripetal body 5 that supports a probe 9 to be mounted on an IC socket mounted on a circuit board to be inspected, a bush 2 that supports the centripetal body 5 in a state where a movable range is limited, and It is composed of a frame 15 interposed to fix the bush 2 to the movable base of the automatic insertion device.

The frame 15 serves as a base for supporting the components of the jig and, at the same time, in an automatic inspection device,
In order to automatically insert the probe 9 into the C socket, the probe 9 is directly fixed to a movable base which is mechanically moved vertically or horizontally or vertically. The frame 15 of the present embodiment is a metal flat plate provided with a support hole 16 penetrating vertically, and a reinforcing plate 17 is hung from one side of the flat plate. On the other hand, the bush 2 has a mortar-shaped bearing hole 1 at the center, and a flange 18 is integrally provided around the center of the peripheral surface. The lower surface of the flange portion 18 has its bearing hole 1 formed perpendicularly to the lower surface of the flange portion 18 so that it can function as a support surface when fixing the bush 2 to the frame 15.

The frame 15 and the bush 2 are provided with support holes 16
The lower part of the bush 2 is fitted in the upper part of the bush 2, and the upper surface of the frame 15 and the lower surface of the flange portion 18 are in close contact with each other with screws. A pair of bearing parts 19, 19 are provided on the upper surface of the flange part 18.
Are symmetrically fixed to the bearing hole 1 of the bush 2, and the cam followers 7, 7 are rotatably supported by the bearings 19, 19 with bolts pointing in the radial direction with respect to the bearing hole 1 of the bush. .

The centripetal body 5 comprises a horizontal vibration transmitting means 4, a centripetal shaft 13 and a connecting member 20.

Most of the centripetal shaft 13 is in the form of a rod-shaped rotating body, has a cylindrical shape with the smallest cross-sectional area from the lower portion to the middle portion, and forms a tapered portion 3 that widens upward from the middle portion to the upper portion. Has been done. A ring-shaped cam portion 21 that restricts rotation of the centripetal shaft 13 is integrally formed on the upper portion of the taper portion 3, and a concave portion 22 that opens upward is provided in the center portion thereof, and an upward and downward concave portion 22 is provided at the edge portion. A pair of penetrating cam grooves 6, 6 are formed symmetrically with respect to the recess 22 with a width substantially equal to the diameter of the cam followers 7, 7. It is desirable that the width and depth of each cam groove 6, 6 be set so that an appropriate clearance is generated when the cam followers 7, 7 slide. What is a proper clearance?
For example, when using the probe 9 in which the contact terminals 8 are arranged similarly to the pin arrangement of the IC or the like, a deflection substantially equal to the pin pitch of the IC or the like is generated in the vertical and horizontal directions or the rotation direction at the contact terminal 8 portion of the probe 9. It is something that occurs.

The connecting member 20 is detachably interposed between the lower portion of the centripetal shaft 13 and the probe 9 and has a role of transmitting the motion of the centripetal shaft 13 to the probe 9 which is determined by the shapes of the bush 2 and the tapered portion 3. A spring 2 that fulfills and biases the centripetal body 5 downward with respect to the bush 2.
It becomes the emphasis point of 3. The connecting member 20 has a columnar shape with a cross-sectional size substantially equal to the outer diameter of the spring 23 to be mounted, and has an annular notch at the upper peripheral edge of the connecting member 20, which serves as the force point, into which one end of the spring 23 fits. An upper hole 24 into which the lower portion of the centripetal shaft 13 is fitted is formed in the center of the upper surface of the connecting member 20, and a lower hole 26 into which the rod 25 of the probe 9 is fitted is formed in the lower surface center. A screw hole communicating with the upper and lower holes 24 and 26 is horizontally formed in the lower portion, and a set screw screwed into the screw hole is connected to the centripetal shaft 13 and the probe 9.

The fulcrum for the force point of the spring 23 is the lower surface of the frame 15. On the lower surface of the frame 15,
Although the notch or the like for fitting one end of the spring 23 is not provided, the diameter of the lower portion of the bush 2 fitted in the support hole 16 is set to be substantially equal to the inner diameter of the spring 23, and the frame 1
If the lower end of the bush 2 is projected from the lower surface of the frame 15 in a state where the upper surface of 5 and the lower surface of the flange portion 18 are in close contact with each other, the protruding portion and the spring 23 are fitted, and the position of the spring 23 is stable. Will be done.

According to the present invention, the main body of the centripetal body 5 described above is further provided with the horizontal vibration generating means 4. The horizontal vibration generating means 4 of the present embodiment is one in which a load 27 having an imbalanced balance is attached to the rotating shaft 11 of the motor 10. The motor 10 includes the cam portion 2 of the centripetal shaft 13.
1. Four pillars 28 are erected on the upper surface of 1, and the rotary shaft 11 is directed downward on a seat plate 29 installed at the upper end of the pillar 28. The extension line of the rotary shaft 11 and the central axis of the centripetal shaft 13 coincide with each other. To fix it.

The load 27 has a disk-shaped eccentric weight 12 in which a flange 31 is provided around the intermediate portion of a connecting shaft 30 that rotates together with the rotating shaft 11 of the motor 10, and the flange 31 is partially cut away. It is the one with screws. The upper part and the lower part of the connecting shaft 30 are each formed with a smaller diameter than the middle part, and the upper part is connected to the connecting member 32 connected to the rotary shaft 11 of the motor 10, and the lower part is divided into two rows of bearings 14, The bearing 14 is attached by a step portion at the boundary between the middle portion and the details and a stop plate 33 screwed to the lower end surface of the connecting shaft 30 so that there is no play in the rotation of the bearings 14, 14. .

The lower portion of the connecting shaft 30 on which the bearings 14, 14 are mounted is fitted into a recess 22 formed in the center of the upper surface of the cam portion 21 of the centripetal shaft 13. Recess 22
Has a two-step hole with a wide upper portion and a narrow lower portion, and the centers of the upper and lower portions are located on an extension line of the rotating shaft 11 of the motor 10. The small diameter portion of the concave portion 22 is a housing portion for a screw to which the stop plate 33 is fixed, and the large diameter portion is a portion for housing the bearings 14, 14. Therefore, the diameter of the large diameter portion is set to be equal to the outer diameter of the bearing 14, and the depth thereof is set to be slightly larger than the thickness of the two rows of the bearing 14. By inserting a ring-shaped lid member 34 onto the upper surface of the cam portion 21 with a screw, the penetrating portion 3 provided along the edge of the hole in the center of the lid member 14
5 is a bearing 1 attached to the lower part of the connecting shaft 30
4, the lower edge of the bearing 14 is in contact with the step of the inner wall of the recess 22. Therefore, the lower portion of the connecting shaft 30 fitted in the recess 22 cannot be removed.

Thus, the horizontal vibration generating means 4, the centripetal shaft 13 and the connecting member 20 are integrally suspended in the bearing hole 1 of the bush 2, and the restoring force of the spring 23 keeps the state stable.

An appropriate spring constant of the spring 23 is
Although it depends on the weight balance between the upper and lower parts of the centripetal body 5, when selecting the spring constant of the spring 23 to be used, the upper limit that does not damage the pin terminals of the socket by the pressure applied when the spring 23 is compressed Then, the centripetal body 5 does not wobble unnecessarily due to the movement of the jig, and even if the centripetal body 5 wobbles, the centripetal body 5 must be set within a lower limit range that can be instantly returned to the fixed position. It should be noted that the surfaces of the pin terminals arranged in the socket are not all located at the same height, and some variations inevitably occur. Therefore, in order to bring the contact terminals 8 into contact with all the pin terminals, the spring 23 Must have greater elasticity than either the pin terminal of the socket or the contact terminal 8 of the probe 9. Rubber and elastic resin are present as the same effects as the spring 23. Various selections are possible such as using an elastic member formed by molding them into a cylindrical shape.

The vibration frequency of the horizontal vibration generating means 4 (1
As the number of rotations of the motor per second), when a value is set to periodically apply a force to the centripetal body 5 at a frequency equal to its natural vibration, the vibration of the horizontal vibration generating means 4 and the vibration of the centripetal body 5 are resonantly amplified. Since it may be difficult to make a normal contact, it is necessary to adjust the rotation of the motor 10 to generate vibration at a non-resonant frequency, or to adjust the spring constant, the length of the centripetal shaft 13, and the weight of the eccentric weight 12. It is desirable to change it so that natural vibration that does not cause resonance with the vibration frequency occurs.

The present embodiment is constructed as described above, and the probe 9 is suitably attached to the IC socket mounted on the circuit board to be inspected by the jig fixed to the movable base of the automatic insertion device, and each pin of the IC socket is attached. The circuits connected to the terminals are inspected one after another. The probe 9 is mounted on the IC socket while the horizontal vibration generating means 4 is generating minute vibrations. Therefore, even if there is some misalignment in the vertical and horizontal directions or the rotational direction in the mounted state of the IC socket, the contact terminal is brought to the position of the pin terminal. 8 is preferably induced, and when they come into contact with each other, they also rub against each other to remove foreign matter and an oxide film. The vibration stops when a predetermined time has elapsed after the two contact, and the elasticity of the biasing member ensures that the pin terminals and the contact terminals 8 are in contact with each other and the state is maintained.

Further, the horizontal vibration generating means 4 and the centripetal shaft 1
By interposing the bearing 14 which is securely fixed in position with the No. 3 bearing, high-quality bearings are formed at both ends of the rotating load 27, the rotational runout of the load 27 is prevented, and the rotation is smooth, and horizontal vibration is generated. The uniform centripetal body 5 including the means 4 generates uniform vibration only by moving the center of gravity.

[0022]

As described above, when the jig for inspecting a circuit board according to the present invention is used, the position and the posture of the probe with respect to the movable base of the automatic insertion device are stable in a steady state, and further the horizontal vibration is applied to the position and the posture. Fine-tuned. At the same time, foreign matter on the contact surface of the pin terminal is removed, which greatly reduces contact defects and reduces the frequency of re-inspection, which contributes to a shorter cleaning time for inspections and a shorter delivery time. . Further, by using a probe connected to various sockets, connectors, etc., it can be used for inspection of various circuit boards.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of a jig for inspecting a circuit board according to the present invention.

FIG. 2 is a side view of the jig.

FIG. 3 is a plan view of a bush used for the jig.

FIG. 4 is a sectional view of the bush taken along the line AA.

FIG. 5 is a plan view of an eccentric weight used for the jig.

FIG. 6 is a cross-sectional view of the eccentric weight taken along the line BB.

FIG. 7 is a plan view of the probe used for the jig as seen from below.

FIG. 8 is a cross-sectional view of a main part of the probe.

FIG. 9 is a perspective view showing an embodiment example of an inspection using a jig for inspecting a circuit board according to the present invention.

[Explanation of symbols]

 1 Bearing hole 2 Bushing 3 Tapered part 4 Horizontal vibration generating means 5 Centripetal body 6 Cam groove 7 Cam follower 8 Contact terminal 9 Probe 10 Motor 11 Rotating shaft 12 Eccentric weight 13 Centripetal shaft 14 Bearing

 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Yoshihiro Inoue, Tateyama Machine Co., Ltd., No. 30 Oyama-cho, Kamishinkawa-gun, Toyama Prefecture

Claims (3)

[Claims] 1. A bush (2) having a mortar-shaped bearing hole (1) which is fixed to a movable base of an automatic insertion device and penetrates vertically, and a taper portion (3) which widens upward to fit in the bearing hole (1). A centripetal body (5) having a horizontal vibration generating means (4) attached thereto, and the centripetal body (5) is suspended in a state of being urged downward to the peripheral edge of the bearing hole (1) to form a bush. One of the cam groove (6) and the cam follower (7) sliding along the cam groove (6) is provided on the centripetal body (5) to limit the horizontal rotation of the centripetal body (5) with respect to (2), and the other is bushed. The contact terminal (8) is provided on the tip of the centripetal body (5) in the same manner as the arrangement of the pin terminals of the predetermined socket, and each contact terminal (8) is electrically connected to the circuit board inspection circuit. Characterized in that the connected probe (9) is detachably supported A jig for circuit board inspection. 2. The centripetal body (5) is a motor (10).
A horizontal vibration generating means (4) formed by fixing an eccentric weight (12) to the rotating shaft (11) of the above, and an upwardly expanding taper portion (3) fitted in the bearing hole (1) of the bush (2). The jig for circuit board inspection according to claim 1, wherein the centripetal shaft (13) has a non-detachable coaxial connection with a bearing (14). 3. The circuit board according to claim 1, wherein horizontal vibration generating means (4) vibrating at a non-resonant frequency with respect to the natural vibration of the centripetal body (5) biased downward. Inspection jig.