JP3286578B2 - In-circuit tester - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-circuit tester for inspecting a circuit by moving a test pin three-dimensionally and bringing the test pin into contact with a predetermined position on a test circuit board. The present invention relates to an in-circuit tester that achieves high accuracy, high efficiency operation, and low cost.

[0002]

2. Description of the Related Art In a conventional in-circuit tester, after performing approximate positioning of a test circuit board, precise positioning is performed by making full use of image processing technology using a CCD camera or the like. Inspection of substrate. However, when the image processing technology is used, an image processing system must be added in addition to the mechanical components, and thus there has been a problem that the entire system is increased in size, weight, and cost.

In order to solve this problem, for example, Japanese Patent Publication No. Hei 8-20493 discloses a precision positioning mechanism for performing precise positioning of a test circuit board only by mechanical operation without using image processing technology. ing. This precision positioning mechanism is provided with a mechanical structure in which two reference holes provided at predetermined positions on a test circuit board are sandwiched with a time difference from both ends and a positioning pin and a receiving portion are fitted to each other. And the two-dimensional position of the rotation direction can be precisely positioned.

[0004]

However, although the above-described precision positioning mechanism can realize precision positioning only by a mechanical structure, the precision positioning is limited to two-dimensional precision positioning, and the precision positioning is performed by manual operation. However, there is a problem that the operation is troublesome and the work efficiency is poor. Here, if the precision positioning mechanism is to be automated, there is a possibility that the size and weight of the mechanism will be greatly increased, and a problem that the cost will be increased will occur.

[0005] Even if the precise positioning is performed, in the actual inspection, the position of the test pin must be corrected for the precisely positioned test circuit board, that is, coordinate conversion processing must be performed. In the precision positioning mechanism using the processing technology, the position of the test circuit board is corrected by the image processing technology every time the test circuit board is installed, so that the work efficiency of the inspection of a plurality of test circuit boards is extremely low. There were also points.

Further, in the conventional automated in-circuit tester, the test pins are moved three-dimensionally at a high speed, so that the vibration due to acceleration and deceleration at both ends of the moving area is large, and this vibration adversely affects the internal inspection operation. Also, there is a problem that noise due to vibration is generated to the outside.

In this case, in the conventional in-circuit tester, both the in-circuit tester main body and the external housing have a rigid structure, and the vibration of the in-circuit tester main body is transmitted to the external housing as it is, and the in-circuit tester Lack of overall stability.

In addition, an automated conventional in-circuit tester is generally complicated. For example, to realize a soft landing that lowers the approach speed of a test pin to a test circuit board during an inspection, it is necessary to perform advanced motor drive control. There was a problem that there is.

In addition, in the in-circuit tester using the conventional image processing technique, there is a problem that an error in mechanical positioning and an error caused by blurring or the like due to image processing overlap, and an overall error increases. Was.

Therefore, the present invention eliminates such a problem, and realizes three-dimensional precise positioning and inspection operations basically by only tilt correction and pitch correction for finding a reference origin by mechanical means and reference board measurement. Enhance maintainability and stability, and at the same time, reduce the size and weight, operate with high precision and efficiency,
An object is to provide an in-circuit tester that realizes low cost.

[0011]

The in-circuit tester of the present invention comprises a positioning mechanism (5, 7) for precisely positioning a test circuit board (3) and a clamping mechanism (6, 8);
A probe vertical mechanism (15, 19) for moving test pins (16, 17, 20, 21) in the Z-axis direction to contact the test circuit board, and an XY stage for moving the probe vertical mechanism on the XY plane It has a support frame (57) having a rigid structure to be connected at least, and an outer case (50) having a flexible structure for supporting the support frame, and the outer case is provided with an elastic body (53-56). The positioning mechanism has a first positioning mechanism (5) and a second positioning mechanism (7).
Each of the second positioning mechanism and the second positioning mechanism has a positioning pin (72) forming a fitting protrusion and a receiving part (73) forming a fitting recess, and the positioning pin and the receiver are driven by pneumatic pressure. The portion faces the first and second positioning holes (75) provided at predetermined positions on the test circuit board, and fits by sandwiching the first and second holes. Is positioned at a position defined by the first and second holes, and the positioning by the second positioning mechanism is performed at a predetermined time difference from the positioning by the first positioning mechanism. .

[0012]

[0013]

[0014]

Further, in the in-circuit tester according to the present invention, the clamping mechanism clamps the test circuit board by pneumatic driving after the positioning by the first and second positioning mechanisms is completed.

In the in-circuit tester according to the present invention, the driving by the air pressure is performed by using one air cylinder (61, 81) for each mechanism, and when the positioning or the clamping is completed, a predetermined value is set. Spring (71,
91) The test circuit board is pressed by a predetermined spring force.

Thus, two-dimensional positioning on the XY plane is performed by positioning the positioning mechanism 5 with respect to the first hole and positioning the positioning mechanism 7 with respect to the second hole at a time lag from the positioning operation of the positioning mechanism 5.
Further, the position in the Z direction is determined by the subsequent clamping operation of the clamp mechanisms 6 and 8, and finally the test circuit board is three-dimensionally positioned.

In the in-circuit tester according to the present invention, the position of the test pin is corrected by using the same substrate shape as that of the test circuit board and the positions of at least two predetermined points (the first and second holes). PT1, PT2), detecting the positions of the two points with the test pins, and correcting the coordinate system of the XY stage mechanism based on the detected positions. Characteristically, the coordinate system of the XY stage mechanism is set and corrected according to the tip position of the test pin.

Further, in the in-circuit tester of the present invention, each of the two positions is a circle (173, 17).
4) wherein the reference board has an annular conductor film for each center of the circle, and conducts at predetermined distance units from the vicinity of at least three places of the annular conductor film using the test pins. Performing a check, determining the center of the circle based on at least three conductive positions, and setting a reference origin of the test circuit board, based on a test pin tip position used for the continuity check and the test. Set the reference origin of the test circuit board directly.

In the in-circuit tester according to the present invention, the probe up-and-down mechanism raises and lowers the test pin by a cross-slider crank mechanism that converts a rotary motion into a linear motion, and the test pin is mounted on the test circuit board. On the other hand, soft landing is performed, and vibration near the top dead center and the bottom dead center can be minimized.

Further, in the in-circuit tester according to the present invention, the soft landing further includes decelerating control of the rotational movement near the bottom dead center and near the top dead center where the test pin contacts the test circuit board. Features.

Further, in the in-circuit tester according to the present invention, the test pin has a predetermined inclination with respect to the Z-axis direction, and the test pin is located at a position higher than a reference surface of the test circuit board. When the contact is made, the test pin is moved up and down and rotated according to the force applied to the test pin at the time of the contact, and the tip of the test pin is moved in the Z direction while being in contact with the test circuit board. I do. As a result, even when the test pins come into contact with the test circuit board, the test pins do not bend significantly, the damage to the test circuit board is minimized, and the test circuit board is not displaced in the XY directions.

In the in-circuit tester according to the present invention, the test pins are notched in a circumferential direction of the test pins facing the test circuit board and along an axial direction of the test pins. The test pin has three grooves (R) at a section perpendicular to the axis of the test pin having a groove.
(a, Rb, Rc).

Further, in the in-circuit tester according to the present invention, the test pin is rotatable by 90 degrees around a predetermined Z axis.

[0025]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 are a plan view, a front view, and a left side view, respectively, showing the entire configuration of an in-circuit tester according to an embodiment of the present invention.

1 to 3, the present in-circuit tester 1 has a slide plate 2 on which a test circuit board 3 is mounted and which moves the mounted test circuit board to almost the center of the bottom of the support frame 57. The slide plate 2 can be moved by moving the lever 4 in the X direction.

That is, the lever 4 is integrated with the slide plate 2 via the rod 4a and the member 4b fixed to the bottom surface of the slide plate 2 via the rod 4a.
A pulley 4d is attached to a portion where the rod 4a penetrates through the outer casing 50, and an elongated hole guide corresponding to the moving range of the levers 4 and 4 'is provided. The pulley 4d moves along the elongated hole guide. As a result, the slide plate 2 moves, and the test circuit board 3 on the slide plate 2 is moved.
Moves to the position of the test circuit board 3 '.

The tip of the member 4b in the direction opposite to the moving direction of the slide plate 2 forms a convex portion 4c toward the bottom, and is the bottom of the support frame 57. A notch guide 4g for guiding the portion 4c is formed. A stopper 4e is provided in the moving direction of the slide plate 2, and a stopper 4f for receiving the insertion of the stopper 4e is provided on the support frame 57 side.

The test circuit board 3 'moved to a predetermined position for testing is precisely positioned by the positioning mechanisms 5, 7 and the clamping mechanisms 6, 8. The details of the operations of the positioning mechanisms 5 and 7 and the clamp mechanisms 6 and 8 will be described later.
The origin position of the test circuit board 3 'is determined by previously sandwiching a hole at a predetermined position on the test circuit board 3' with a positioning pin having a tapered end and a receiving portion having a groove receiving the tapered end. After that, the positioning mechanism 7 having the same configuration as the positioning mechanism 5 performs the time difference positioning of determining the rotational position on the X plane by sandwiching another hole on the test circuit board 3 '. Thereafter, the clamp mechanisms 6, 8 clamp the periphery of the test circuit board 3 '. The basic concept of the positioning mechanisms 5 and 7 is described in JP-B-8-20493.

The motors 9 and 11 are connected to test pins 16 and 1
A motor for moving the motors 7, 20, 21 in the X direction. The rotation output of the motors 9, 11 is reduced and transmitted to the pulleys 9b, 11b via the pulleys 9a, 11a, and further, the pulleys 9c, 9d or 11c. , 11d into linear motions in the X direction of the belts 9e, 11e.

The Y-direction guides 10, 12 are provided with belts 9e,
11 e, which guides the movement of the probe up-down mechanisms 15, 19 in the X direction by the driving of the motors 9, 11. The rotation outputs of the motors 14 and 18 are output from pulleys 14a and 14b.
, Or the pulleys 18a and 18b are converted into linear motion in the Y direction by the belt 18c.

Therefore, the probe up / down mechanisms 15, 19
By driving the motors 9 and 11 and the motors 14 and 18,
Each can be moved to any position on the XY plane.

Further, the probe up / down mechanisms 15, 19
By a so-called cross slider crank mechanism, the rotational movement of the motors 22 and 23 is converted into the Z-direction movement of the test pin, that is, the vertical movement. The details will be described later. The test pins 16, 17, 20, and 21 come into contact with a test site, for example, a soldered site on the test circuit board 3 ′ by the vertical movement of the probe up / down mechanisms 15 and 19, and a circuit configuration is obtained based on a conduction result by this contact. Is tested. Therefore, in a normal test, either one of the test pins 16 or 17 of the probe
One of the test pins 20 and 21 of the probe up / down mechanism 19 is used in combination.

The test pins 16, 17, 20,
The test of the test circuit board 3 by 21 is controlled by a preset program or the like, and the test result is stored in a storage device or the like and can be output by an output device. This preset program is
It includes a basic control program for moving test pins in three dimensions in the XYZ directions, and individual application programs in which test locations of various test circuit boards are set in advance.

An area E1 indicates a possible installation area of components and the like arranged on the test circuit board 3 by soldering or the like. Here, since there are various sizes of the test circuit board 3, a mechanism that can be applied to the size of the test circuit board 3 is provided.

That is, the slide plate 2 is an L-shaped plate 34
a, 34b, screws 33 for fixing L-shaped plates 34a, 34b
a, 33b, and grooves 33c, 33d for guiding the movement of the screws 33a, 33b in the X direction.
3b and loosen the L-shaped plates 34a and 34b into the grooves 33c and 33d.
Is moved in the X direction along the
By fixing 3b, the size of test circuit board 3 in the X direction can be adjusted.

For adjustment in the Y direction, the screw 31
This is realized by moving a, 31b along the grooves 32a, 32b. Further, the adjustment in the Y direction is performed by adjusting grooves 37d to 37i and 3 that regulate a predetermined width in the Y direction.
It can be performed by providing an X-direction partition plate inserted into 8d to 38i.

The positioning mechanisms 5, 7 and the clamping mechanisms 6, 8 are also adjusted in accordance with the change in the size of the test circuit board 3. The positioning mechanisms 5 and 7 and the clamp mechanism 6
Adjustment only in the X direction is possible.

That is, the positioning mechanisms 5, 7 and the clamp mechanism 6 are fixed to the support frame 57 by the screws 41 to 43, respectively, but their positions can be readjusted along the grooves 44.

On the other hand, the clamp mechanism 8 can adjust the position in the X direction and the Y direction. That is, although the clamp mechanism 8 is fixed to the support frame 57 by the screw 39, the position in the X direction along the groove 40 can be readjusted.

The clamp mechanism 8 includes screws 35a, 3
5b sets the position in the Y direction.
When the clamps 8a and 35b are loosened, the clamp mechanism 8
a, 36b, can be moved in the Y direction, correspond to the ball 35d, and have grooves 37d to 37i and 38d to 3d.
By setting the balls 35d to the recesses 35d to 35i corresponding to the intervals of 8i, the test circuit board 3 set in advance is set.
Can be readjusted to a position corresponding to the size in the Y direction.

Next, the frame structure of the in-circuit tester 1 will be described with reference to FIGS. FIG. 4-
FIG. 6 is a plan view, a front view, and a left side view of the in-circuit tester 1 for explaining the frame structure. The probe up / down mechanisms 15, 19 and the probe up / down mechanisms 15, 19 are moved in the XY directions, respectively. FIG. 6 is a diagram excluding a XY stage component part.

4 to 6, the XY stage components including the probe up / down mechanisms 15, 19 fixed to the support frame 57, the positioning mechanisms 5, 7, and the clamp mechanisms 6, 8, fixed to the support frame 57, and The slide plate 2 including the test circuit board 3 fixed by the positioning mechanisms 5 and 7 and the clamp mechanisms 6 and 8 is finally fixed to the support frame 57, and these form an integral rigid frame.

On the other hand, the outer casing 50 is formed of a flexible frame. Then, the support frame 5 of the rigid structure frame
7 is a supporting portion 5 of the external housing 50 which is a flexible frame.
They are joined to each other and supported via the first and second members. Elastic bodies 53 to 56 such as rubber are interposed between the support frame 57 and the support portions 51 and 52, and screws 53a to 56a are respectively provided.
Is fixed at four points.

Further, elastic legs 58a to 58d are also provided at the lower four points of the outer casing. The outer casing 50 has a flexible structure as a whole due to its small thickness and the like, but further has the above-described elastic bodies 53 to 56 and the feet 58a.
With the arrangement of ~ 58d, the vibration of the rigid structure frame can be well absorbed, and the operation on the rigid structure frame is not adversely affected.

In this case, the external force acting in the rigid structure frame is only the force generated when the test pins are brought into contact with the test circuit board 3 'by the probe up-down mechanisms 15, 19. Further, since the distance between the position of the center of gravity of the XY stage component and the support point of the support frame 57 in the support portions 51 and 52 is reduced, the moment is reduced with respect to the inertial axial force due to the movement of the XY stage. This also minimizes the vibrations excited in the rigid frame.

Next, the positioning mechanisms 5 and 7 will be described with reference to FIGS. 7 to 9 show a plan view, a front view, and a right side view, respectively, of the positioning mechanism 5, and FIGS. 10, 11, 9, and 12 show the positioning mechanism 5 respectively.
FIG. 5 is a diagram sequentially showing the progress from the start of operation to the end of operation.

In FIGS. 7 to 9, the spring 64 is
The support frame 57 fixed by 1 and the air cylinder 61 are connected, and the air cylinder 61 is pulled upward (+ Z direction) by the spring force of the spring 64 itself. The spring force of the spring 64 itself is maintained even when the distance Sb shown in FIG.

The air cylinder 61 is connected to a lower arm 67 having a receiving portion 73 at the tip.
It moves up and down according to the up and down movement of the air cylinder 61. The stopper 66 connects the upper end of the spring 64 and the stopper 65
Is fixed to a portion connecting the air cylinder 61 and the lower arm 67. Therefore, the stopper 66 limits the lower position of the air cylinder 61, and the stopper 65 limits the upper position of the air cylinder 61.

The piston 63 in the air cylinder 61
The rod 62 is connected to the air cylinder 6
It moves up and down due to the air pressure in 1. The rod 62 has stoppers 68 and 69 fixed to the rod 62.

The spring 71 is interposed between the stopper 69 and the upper arm 70 having the positioning pin 72 at the tip, and presses the upper arm 70. The stopper 68 limits the position of the upper arm 70, which corresponds to the position of the positioning pin 72. The upper arm 70 moves in the axial direction of the rod 62.

Both the upper arm 70 and the lower arm 67 are vertically guided by the guide 74.
The tip of the positioning pin 72 has a tapered shape, and the tip is inserted into the hole 75 of the test circuit board 3 to move the test circuit board 3 to its origin position, that is, the center position of the hole 75 of the test circuit board 3. Will be corrected.

Here, the operation of the positioning mechanism 5 from the start to the end of the operation will be described with reference to FIGS. 10, 11, 9, and 12. FIG. 10 is a diagram illustrating a state at the start of the operation of the positioning mechanism 5. The piston 63 is located at the uppermost position in the air cylinder 61, and the rod 62 is also located at the uppermost position. In this case, the stoppers 65 and 66 are in close contact with each other, and the distance between the stoppers 65 and 66 and the support frame 57 is Sb.

The distance Sb is the same as the distance Sa between the tip of the receiving portion 73 and the test circuit board 3. Further, since the downward movement of the upper arm 70 is restricted by the stopper 68, the distance Sc is maintained between the test circuit board 3 and the lower end of the stopper 68, and the position of the positioning pin 72 corresponding to the stopper 68 is also maintained at this distance. The downward movement is restricted by the stopper 68. As a result, the positioning pins 7
2 and the receiving portion 73 are open at the top and bottom of the test circuit board 3, respectively. Further, the spring 64 is in the most extended state.

In FIG. 11, when the rod 62 is retracted with respect to the air cylinder 61, first, the air cylinder 61 applies the spring force of the spring 64 to the rod 62.
Moves upward relative to. The upward movement of the air cylinder 61 is performed until the distance Sb until the stopper 65 separates from the stopper 66 and comes into contact with the support frame 57 becomes zero.

The lower arm 67 and the receiving portion 73 move upward by the upward movement of the air cylinder 61, and stop at the position where the distance Sa becomes zero. Therefore, by adjusting the position of the head of the adjusting screw 65a fixed to the support frame 57, the distance Sb is adjusted, and furthermore, the distance Sa is adjusted.
Is adjusted, the vertical position of the test circuit board 3 can be adjusted as a result.

In FIG. 9, when the rod 62 is further pulled into the air cylinder 61, the rod 62 moves relatively downward with respect to the support frame 57. With this downward movement, the stoppers 68 and 69 also move downward. Therefore, the upper arm 70 and the positioning pin 72
Moves downward by the amount of downward movement of the rod 62, that is, the distance Sc. The lower end of the stopper 68 is
Since 2 corresponds to the insertion position of the hole 75 of the test circuit board 3, the reference point of the test circuit board 3 is positioned at this time.

In FIG. 12, when the rod 62 is further retracted with respect to the air cylinder 61, the rod 62 moves further downward relative to the support frame 57. However, since the positioning pin 72 has already been inserted into the hole 75 in the state of FIG. 9, it does not move further downward, and the upper arm 70 does not move downward.

For this reason, the stopper 68 is connected to the upper arm 7
0, and the spring 7 is moved downward by the stopper 69.
1, the upper arm 70 is pressed. As a result, the positioning pin 72 and the receiving portion 73 press the test circuit board 3 by the spring force of the spring 71, and maintain a state where the test circuit board 3 is positioned at an accurate vertical position where the test circuit board 3 can be adjusted.

From the final positioning state shown in FIG.
The transition to the original positioning start state is performed in the reverse order of the operation described above. In this case, in the same way as the operation from the start position of positioning to the final end position of positioning is performed by increasing or decreasing the air pressure of the air cylinder 61,
The operations from the final positioning end state to the original positioning start state are all performed only by increasing or decreasing the air pressure of the air cylinder 61.

In this manner, the positioning mechanism 5 shifts to the final positioning end state, during which the positioning mechanism 7 performs the same operation as the positioning mechanism 5 with a slight time difference. For example, after the positioning mechanism 5 completes the state of FIG. 9, a time difference is provided so that the positioning mechanism 7 becomes the state of FIG. Thus, after the home position of the test circuit board 3 is positioned by the positioning mechanism 5, the positioning mechanism 7 performs positioning in the rotation direction about the home position, and the test circuit board 3
This means that the two-dimensional position has been positioned.

Next, the clamp mechanisms 6 and 8 will be described with reference to FIGS. 13 to 15 show a plan view, a front view, and a right side view of the clamp mechanism 6, respectively. FIG. 16 shows a state at the start of operation of the clamp mechanism 6 as in FIG. 10, and FIG. It shows a state similar to FIG.

The structure and operation of the clamp mechanism 6 shown in FIGS. 13 to 16 are substantially the same as those of the positioning mechanism 5 shown in FIGS. 7 to 12. The difference between the clamping mechanism 6 and the positioning mechanism 5 is that the clamping mechanism 6 is different from the positioning pin 72 and the receiving section 7.
The point corresponding to No. 3 is the shape of the clampers 92 and 93, respectively. The shapes of the clampers 92 and 93 are different from the positioning pins 72 and the receiving portions 73, and the distal ends thereof have a shape extending in the peripheral direction of the test circuit board 3 so that the test circuit board 3 is securely clamped so as not to bend. I have to.

The clamping operations of the clamping mechanisms 6 and 8 are controlled so as to clamp at the same time. However, clamping is performed at the same time after the two-dimensional positioning by the positioning mechanisms 5 and 7 is completed. By the clamping operation of the clamp mechanisms 6, 8, the test circuit board 3 is securely held so as to eliminate the influence of the external force, and the position correction in the Z direction on the XY plane is performed.
The three-dimensional position correction is precisely performed by the use of the clamp mechanism 7 and the clamp mechanisms 6 and 8.

As with the positioning mechanisms 5 and 7, the clamp mechanisms 6 and 8 adjust the vertical position of the lower clamper 93 by adjusting the adjustment screw 85a, and as a result, the vertical position of the test circuit board 3 is adjusted. Will be.

The positioning mechanisms 5, 7 and the clamping mechanisms 6, 8 are each operated by one air cylinder, and the positioning positions of the positioning pins 72 and the receiving portions 73 and the clamping positions of the clampers 92, 93 are determined by the rods. Since the distance can be shortened, the positioning mechanisms 5 and 7 and the clamp mechanisms 6 and 8 can be reduced in weight and size as a whole.

Next, the probe up / down mechanisms 15 and 19 will be described with reference to FIGS. FIG. 17 is a plan view, a front view, and a left side view of the probe up / down mechanism 19, respectively. First, the probe 100 will be described. The probe 100 holds a test pin 21 inclined at 5 degrees with respect to the Z-axis direction and a test pin 20 inclined at 15 degrees with respect to the Z-axis direction.

FIG. 20 is a view showing a cross section near the test pin 21 in the cross section taken along the line A--A.
The direction is precisely maintained by the cylindrical bush 105 and the guide 101. In this case, the guide 101 is disposed closer to the tip of the test pin 21 than the bush 105. The guide 101 is made of Delrin resin.

FIG. 21B is a sectional view taken along the line CC.
The test pin 21 can penetrate the inner cylindrical hole of the bush 105 and slide. In this case, the clearance between the test pin 21 and the bush 105 is 0.
1 mm.

On the other hand, FIG. 21A is a cross-sectional view taken along the line BB. The guide 101 has a cross-sectional shape of a “recess”, and the width of the recess in the Z direction is the diameter of the test pin 21. And the test pin 21 is in contact with the bottom surface of the concave portion. That is, in FIG. 21A, the test pin 21 is in contact with the recess at only three points Ra, Rb, and Rc.

Here, a force P 1 is applied to the point Ra in the −X direction due to the contact with the test circuit board 3. Moreover,
Since the guide 101 has a “concave” cross section, it can be processed with high accuracy and can be processed with zero error. Since the bush 105 is slidable around the entire circumference of the test pin 21, the frictional resistance is extremely large. On the other hand, since the guide 101 is a three-dot line contact, the frictional resistance is extremely large. small.

As described above, the bush 105 and the guide 10
By using in combination with 1, the clearance in the YZ plane can be made very small, and the linearity of the test pin 21 can be maintained with high accuracy.

Next, the protrusion of the test pin 20 will be described. The two test pins 20 and 21 have their tips separated by about 0.3 mm.
0 and 21 will be used. When the test pin 21 is used, the test pin 20 is retracted as shown in FIG. 18, and when the test pin 20 is used, the test pin 20 is protruded to the tip position of the test pin 21,
The test pin 21 will be retracted.

Therefore, the test pin 20 can be protruded or retracted by the air cylinder 120. In the state of FIG. 18, the test pin 20 is retracted, but when the test pin 20 is protruded from this state to the tip end of the test pin 21, the rod 122 is guided by the guide 121 by the air cylinder 120, and When moved in the (Z direction), the test pin 20 of the swing member 123 that swings about the shaft 124 is moved.
The portion that comes into contact with the rear end turns left and the test pin 20 protrudes.

In this case, the rear end of the test pin 20 is pulled by the spring 125 and is kept in contact with the swing member 123 at all times. When the test pin 20 is projected and retracted, the guide groove 110 is
The directionality is maintained by sliding of 5. In this way, the test pin 20 is driven to protrude and retract by the air cylinder 120.

Incidentally, although the test pins 20 are set at an inclination of 15 degrees with respect to the Z-axis direction, the test circuit board 3 may shift in the Z direction. Considering what is required of the test pins 20 in such a case, first, as shown in FIG.
Is shifted by x in the Z direction, and the test pin 2 having the initial length l
An angle β1 of 0 becomes an angle β2, and an angle α1 with the Z axis becomes an angle α2. Further, assuming that the initial length of the test pin 20 in the Z-axis direction is b and the length in the X direction is a, the displacement amount δ of the length of the test pin 20 is δ = l−SQRT (a ＾ 2 + ( b−x) ＾ 2). However, "SQRT" means square root,
"＾" means power. On the other hand, the rotation angle θ at point A, which is the base of the test pin 20, is as follows: θ = β1−β2 = arctan (b / a) −arctan ((b−x) / a)

Therefore, if the point A does not rotate according to the rotation angle θ, the test pins 20 may be bent due to the rise of the test circuit board 3 as shown in FIG.
As shown in FIG. 22C, the test circuit board 3 is shifted in the −Z direction by the distance d1 (d1 = x · tan (α1)). Specifically, α1 = 15 degrees, x = 5 m
m, l = 103 mm, a = 26.7 mm, b = 99.5
mm, the displacement amount δ = 4.8 mm and the rotation angle θ = 0.
76 degrees, the displacement distance d1 = 1.34 mm.

For this reason, it is necessary to adjust the height of the tips of the test pins 20 and 21 according to the height of the test circuit board 3. When the height of the test circuit board 3 is small, the height is adjusted by moving the test pins 20 and 21 up and down, and when the height of the test circuit board 3 is large, the head or probe 100 to the rod 130 are integrated. The height of the part thus adjusted is adjusted by vertical movement adjustment with respect to the arm 130a. When the test pins 20 and 21 are moved up and down, the precision guide by the guides 101 and 102 described above is effective.

Although the height adjustment described above is an initial adjustment performed before the start of the inspection, the test pins 20 and 21 come into contact with the test circuit board 5 during the inspection operation. According to the height of the circuit board, the length and angle of the test pin must be automatically adjusted.

More specifically, the test pin 21 having an angle of 5 degrees is such that when stress is applied to the tip of the test pin 21,
The tip of the test pin 21 is rotated about the rotation axis 200 in the −X direction, and the tip of the test pin 21 is returned to the original position by the restoring force of the spring 125.
The tip of the test pin 21 is retracted by the spring force of a spring (not shown) inserted between them, and when there is no stress, the tip of the test pin 21 returns to the original position.

On the other hand, a test pin 2 having an angle of 15 degrees
0, when stress is applied to the tip of the test pin 20, the tip of the test pin 20 is rotated in the −X direction around the screw 115, and the restoring force of the spring 125 returns the tip of the test pin 20 to the original position. The test pin 2 is moved by the spring force of a spring (not shown) inserted into the base of the test pin 20.
When the leading end of the test pin 20 is retracted and the stress disappears, the leading end of the test pin 20 returns to the original position.

As described above, even if the test pins 20, 21 are stressed during the inspection due to the unevenness of the test circuit board surface, the rotation of the test pins 20, 21 and the vertical movement of the test pins 20, 21 cause the test pins 20, 21 to move. Since the tip moves up and down in the Z-axis direction, the bending of the test pins 20 and 21 is eliminated to protect the test pins 20 and 21, and the test pins 20 and 21 are prevented from being damaged and the test circuit board is prevented from being damaged. The forced displacement in the XY directions can be eliminated.

Next, the vertical movement mechanism of the probe 100 by the probe vertical movement mechanism 19 will be described. This probe 1
The up-and-down mechanism of the probe 00
This is achieved by a so-called cross-slider crank mechanism, which converts the motion into a vertical motion of 00.

The probe 100 is connected to a rod 130, and moves up and down by moving the rod 130 up and down. The rod 130 moves up and down via a spline mechanism 140 that allows axial movement, and is connected to a slider 131 via an arm 130a fixed to the rod 130.

Therefore, the slider 131 is
, The rod 130 and the probe 100 move up and down accordingly. The slider 131 has a horizontally long opening 131a, and a crankpin 133 is inserted into the opening 131a, and the crankpin 133 slides on a peripheral surface of the opening 131a. Crank bar 134
Supports the crank pin 133 and the motor 2
3 is attached to the output shaft. Therefore, the rotation of the motor 23 becomes the rotation of the crank bar 134 and the crank pin 1
33 rotates with a predetermined radius.

The rotation of the crank pin 134 causes the slider 131 to move up and down in the Z direction.
The vertical movement of the slider 131 is caused by the crank pin 13
Since the rotation of No. 3 is directly converted into a vertical motion, the speed of the vertical motion draws a so-called sine curve of a trigonometric function as time elapses, as shown in FIG.
Accordingly, the speed of the vertical movement near the upper limit or the lower limit becomes gentle, and especially at the point where the test pins 20 and 21 come into contact with the surface of the test circuit board 3, the speed becomes almost zero,
The so-called soft landing, which reduces the impact generated when the test pins 20 and 21 come into contact with the test circuit board 3, can be achieved.

In particular, the soft landing is achieved only by a mechanical drive such as a cross slider / crank mechanism, and it is not necessary to perform special motor control to realize the soft landing. Moreover, the motor 23
Is only one-way rotational movement, for example, only one rotation,
The vertical movement of the probe 100 and the soft landing can be realized at the same time, and there is no need to reversely rotate the motor 23 every time the probe 100 is moved up and down.

Note that the rotational speed of the motor 23 is
When the drive control for decelerating near the lower limit E10 of 00 is further used, a more sufficient soft landing can be realized as shown by the curve L1.

Incidentally, as described above, the rod 130
Is configured such that only vertical movement is allowed by a spline mechanism 140. The spline mechanism 140 is used for the probe 1
This is because the rotation of 00 can be controlled by 90 degrees about the axis of the rod 130.

That is, the motor 150 is
The output shaft 151 is rotated by performing a predetermined deceleration inside. The output shaft 151 is connected to the gear 152 via a clutch, and rotates the gear 152. The gear 153 hits the stopper and stops. A lower current is applied to the motor 150 than at the time of the rotation drive, and the motor 150 maintains the rotation position. Since the gear 153 is connected to the spline mechanism 140,
Probe 100 can be rotated about the axis of rod 132. As a result, the original position Q3 of the tip of the test pin attached to the probe 100 is 90 degrees on the XY plane.
It is rotated to the position Q4 rotated by degrees. The rotation from the position Q4 rotated by 90 degrees to the original position Q3 is also performed by the motor 15.
This is achieved by a drive control of zero.

The 90-degree rotation of the probe 100 is caused by the presence of an obstacle or the like, with respect to a target point on the test circuit board 3 which cannot be tested in the X direction.
The test from the Y direction is enabled.

Next, the position correction of the test pin tip will be described. The position correction of the test pin tip is performed using the position correction reference board 170 shown in FIG. On the surface of the reference board 170, a predetermined position PT
1, PT2, that is, corresponding to the center position of the circle,
The conductor film has circles 173 and 174 having a predetermined width.

The circles 173 and 174 are formed by etching or the like. Similarly to the test circuit board 3, the reference board 170 has a guide hole 171 for defining the origin PT0 of the reference board 170 in the lower left corner thereof,
And a guide hole 172. The guide hole 171 is a guide hole that is precisely positioned by the positioning mechanism 5,
The guide hole 172 is a guide hole that is precisely positioned by the positioning mechanism 7. Therefore, the guide holes 171, 1
PT1, PT on the two-dimensional plane determined by 72
By calculating the position of No. 2, the position correction of the tip of the test pin is performed based on the points PT1 and PT2.

First, as shown in FIG. 25, the positions of the points PT1 and PT2 are, for example, in an area E including a part of a circle 173.
At 21, the test pin PB is moved from the predetermined position inside the circle 173 toward the circle 173 by a predetermined distance unit, and the position when the test pin PB first contacts the circle 173 is obtained. The position when the pin PB first contacts the circle 173 is determined, and the position when the test pin PB first contacts the circle 173 is determined in the area E23. The center of the circle 173 is determined based on the three positions thus determined. Is determined.

Similarly, the position PT1 at the center of the circle 174
Are also determined from the three contact positions determined in the regions E24 to E26. The XY drive coordinate system of the test pins is corrected based on the obtained positions of the two points PT1 and PT2 in accordance with the current installation state of the reference board 170.

In this case, one test pin corresponds to each circle 17
Since it is necessary to detect the positions of three points for each of 3,174, the position detection of a total of six points is performed. Further, since each test pin can be rotated by 90 degrees about the Z axis, an additional six points are detected. Since the position of a point is detected, the position of 12 points is finally detected for one test pin. Therefore, since the test is usually performed using two test pins, the position detection of 24 points is performed.

The first contact of the test pin PB with the circles 173 and 174 is made by the detection unit 175 provided on the closed circuit between the test pin PB and the circle 173 and on the closed circuit between the test pin PB and the circle 174. This is done by detecting conduction. This detection unit 175 may be a buzzer,
It may be a relay. If it is a buzzer, note the current coordinates of the test pin PB at that time, and
1 and PT2, the position is corrected, and if the relay is a relay, the test pin P
An instruction to correct the position of the current coordinates of B in the coordinate system of the reference points PT1 and PT2 is transmitted to a control system (not shown). Although the above three points on the circles 173 and 174 are driven from the inside of the circles 173 and 174, the points may be driven from a predetermined position outside the circles 173 and 174.

The positions of the points PT1 and PT2 are determined after detecting the positions of the three points on the circles 173 and 174. However, the positions of the points PT1 and PT2 are determined using the test pins PB. 173, 174
However, the present invention is not limited to those using. Of course, the method using the circles 173 and 174 is advantageous in that the points PT1 and PT2 can be obtained more accurately because the error generated when the test pin PB is driven is dispersed in each of the three points.

By previously correcting the position of the test pin tip using the reference board 170 before the test, a plurality of test circuit boards 3 can be continuously tested, and an efficient test can be performed. Is achieved. In addition, since the error in the position correction of the test pin tip is an error only in the mechanical system, the error is smaller than the overall error between the blur of the image outline and the control error of the mechanical system when image processing is used together. In addition to achieving high-accuracy position correction, the complexity, size, weight, and cost of image processing can all be drastically reduced.

In the above embodiment, the in-circuit tester has been described as an example. However, the present invention is not limited to this.
Obviously, the present invention can be applied to a circuit tester of a circuit board itself on which components such as an IC are not installed.

[0101]

As described above in detail, in the in-circuit tester of the present invention, the positioning mechanism and the clamp mechanism for precisely positioning the test circuit board, and the test pins are moved in the Z-axis direction to contact the test circuit board. Since it has a rigid support frame that couples at least an XY stage that moves the probe up / down mechanism and the probe up / down mechanism on the XY plane, and a flexible external housing that supports the support frame, The flexible external housing absorbs the vibration of the in-circuit tester main body coupled to the support frame, and has the advantage that the external vibration is reduced as much as possible without adversely affecting the operation function of the in-circuit tester main body. .

Further, in the in-circuit tester of the present invention, since the outer casing supports the support frame via the elastic body, the vibration generated by the in-circuit tester body can be further reduced. It has the advantage of being able to.

Further, in the in-circuit tester of the present invention, the positioning mechanism has a first positioning mechanism and a second positioning mechanism, and each of the first and second positioning mechanisms has a fitting projection. A positioning pin and a receiving part forming a fitting recess, wherein the positioning pin and the receiving part driven by air pressure are provided on a first position for positioning provided on a predetermined position on the test circuit board. And the second
Face, the first and second holes are sandwiched and fitted,
The test circuit board is positioned at a position defined by the first and second holes;
In the present invention, the positioning by the second positioning mechanism is performed at a predetermined time difference from the positioning by the first positioning mechanism, so that the two-dimensional position of the test circuit board is automatically positioned. Has the advantage that

In the in-circuit tester according to the present invention, the clamp mechanism clamps the test circuit board by driving air after completion of the positioning by the first and second positioning mechanisms. There is an advantage that the three-dimensional position of the test circuit board can be automatically and precisely positioned.

In the in-circuit tester according to the present invention, the driving by the air pressure is performed by using one air cylinder for each mechanism, and when the positioning or the clamping is completed, a predetermined spring force of a predetermined spring is applied. Because the test circuit board is pressed by
There are advantages that the positioning mechanism and the clamp mechanism can be reduced in size, and that the test circuit board can be securely held.

In the in-circuit tester according to the present invention, the position of the test pin is corrected by adjusting the position of at least two predetermined points with the first and second holes in the same board shape as the test circuit board. Since the position of the two points is detected by the test pin and the coordinate system of the XY stage mechanism is corrected based on the detected position, mechanical detection is performed. The position of the test pin can be corrected only by the mechanism, and the position is corrected by the mechanical detection mechanism, so that a superimposed error occurs as in the case of using indirect means such as image processing technology. Therefore, there is an advantage that the expansion of the error can be suppressed.

Further, in the in-circuit tester of the present invention, each of the two positions is a center position of a circle, the reference board has an annular conductive film for each center of the circle, and the test pin A conduction check is performed for each predetermined distance unit from at least three locations in the vicinity of the annular conductor film using at least a predetermined distance unit, a center of the circle is obtained based on at least three conducted positions, and a reference origin of the test circuit board is determined. It is characterized by setting and detecting three positions dispersed in four directions from the center of the circle, so that the measurement error of the center position of the circle is dispersed, and as a result, highly accurate position detection can be performed. It has the advantage of being able to.

In the in-circuit tester according to the present invention, the probe up / down mechanism raises / lowers the test pin by a cross-slider / crank mechanism that converts a rotary motion into a linear motion, and the test pin is mounted on the test circuit board. On the other hand, since the soft landing is performed, the soft landing can be realized only by the mechanical mechanism, and there is an advantage that vibration near the top dead center and the bottom dead center is minimized.

In the in-circuit tester according to the present invention, the soft landing further controls the rotational movement in the vicinity of the bottom dead center and the vicinity of the top dead center where the test pin contacts the test circuit board. Therefore, there is an advantage that the surface of the test circuit board can be prevented from being damaged and the test pins can be prevented from being worn or damaged.

Further, in the in-circuit tester according to the present invention, the test pins have a predetermined inclination with respect to the Z-axis direction, and the test pins are located at a position higher than a reference surface of the test circuit board. When the contact is made, the test pin is moved up and down and rotated according to the force applied to the test pin at the time of the contact, so that the tip of the test pin is moved in the Z direction while being in contact with the test circuit board. Therefore, even when the test pins come into contact with the test circuit board, the test pins do not bend significantly, and have the advantage that damage to the test circuit board is minimized and the test circuit board is not displaced in the XY directions.

Further, in the in-circuit tester of the present invention, the test pins are notched along the circumferential direction of the test pins facing the test circuit board surface and along the axial direction of the test pins. The test pin has a groove, and is guided by a guide member that contacts the test pin at three points in a cross section perpendicular to the axis of the test pin,
Since this guide member is easy to perform precision processing, there is an advantage that the guide of the test pin can be accurately performed as a result.

Further, the in-circuit tester of the present invention has an advantage that the test pin can be rotated 90 degrees around a predetermined Z axis, so that flexible measurement is possible.

[Brief description of the drawings]

FIG. 1 is a plan view showing an overall configuration of an in-circuit tester according to an embodiment of the present invention.

FIG. 2 is a front view showing the overall configuration of an in-circuit tester according to an embodiment of the present invention.

FIG. 3 is a left side view showing an overall configuration of an in-circuit tester according to an embodiment of the present invention.

FIG. 4 is a plan view showing a configuration of an in-circuit tester for explaining a frame structure.

FIG. 5 is a front view showing a configuration of an in-circuit tester for explaining a frame structure.

FIG. 6 is a front view showing a configuration of an in-circuit tester for explaining a frame structure.

7 is a plan view of the positioning mechanism 5. FIG.

8 is a front view of the positioning mechanism 5. FIG.

9 is a right side view of the positioning mechanism 5. FIG.

FIG. 10 is a right side view of the positioning mechanism 5 when a positioning operation is started.

FIG. 11 is a right side view when the receiving portion 73 of the positioning mechanism 5 operates.

FIG. 12 is a right side view when the positioning operation of the positioning mechanism 5 is completed.

13 is a plan view of the clamp mechanism 6. FIG.

14 is a front view of the clamp mechanism 6. FIG.

15 is a right side view of the clamp mechanism 6. FIG.

FIG. 16 is a right side view of the clamp mechanism 6 at the start of the clamping operation.

17 is a plan view of the probe up / down mechanism 19. FIG.

18 is a front view of the probe up / down mechanism 19. FIG.

19 is a left side view of the probe up / down mechanism 19. FIG.

FIG. 20 is a view showing a cross section near the test pin 21 in the cross section taken along the line AA.

FIG. 21 is a cross-sectional view taken along line BB near the test pin and CC.
It is a line sectional view.

FIG. 22 is a diagram illustrating a state where the test circuit board 3 is shifted upward.

FIG. 23 is a diagram showing soft landing by a cross slider crank mechanism.

FIG. 24 is a diagram showing the surface of a reference board 170.

FIG. 25 is a diagram illustrating position correction using a reference board 170.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... In-circuit tester 2 ... Slide board 3 ... Test circuit board 4 ... Lever 5,7 ... Positioning mechanism 6,8 ... Clamp mechanism 9,11,14,18,22,23,150 ... Motor 10,12 ... Y direction Guides 15, 19 Probe vertical mechanism 16, 17, 20, 21 Test pins 50 External housings 51, 52 Supports 53-56 Elastic bodies 57 Support frames 61, 81 Air cylinders 62, 82 Rod 63, 83 ... piston 64, 71, 84, 91 ... spring 65, 66, 68, 69, 85, 86, 88, 89 ... stopper 67 ... lower arm 70 ... upper arm 72 ... positioning pin 73 ... receiving parts 92, 93 ... Clamper 100 ... Probe 131 ... Slider 133 ... Crank pin 134 ... Crank bar 152,153 ... Gear 140 ... Splat Down mechanism 170 ... standards board

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-235344 (JP, A) JP-A-58-175476 (JP, U) JP-A-63-54077 (JP, U) JP-A-1-235344 105873 (JP, U) Japanese Utility Model 60-1888 (JP, U) Japanese Utility Model 49-1730 (JP, Y1) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01R 31/28 G01R 31 / 02

Claims (10)

(57) [Claims] 1. A positioning mechanism and a clamp mechanism for precisely positioning a test circuit board, a probe vertical mechanism for moving a test pin in the Z-axis direction to contact the test circuit board, and moving the probe vertical mechanism on an XY plane. A support frame having a rigid structure that couples at least the XY stage to be formed, and a flexible external housing that supports the support frame, wherein the external housing supports the support frame via an elastic body; The positioning mechanism has a first positioning mechanism and a second positioning mechanism, and each of the first and second positioning mechanisms has a positioning pin forming a fitting projection and a receiving part forming a fitting recess. Wherein the positioning pin and the receiving portion driven by air pressure face first and second positioning holes provided at predetermined positions on the test circuit board. The test circuit board is positioned at a position defined by the first and second holes, and the test circuit board is positioned at a position defined by the first and second holes. An in-circuit tester, wherein the test is performed at a predetermined time difference from the positioning by the first positioning mechanism. 2. The method according to claim 1, wherein the clamp mechanism includes the first and second clamps.
2. The in-circuit tester according to claim 1, wherein after the positioning by the positioning mechanism is completed, the test circuit board is clamped by pneumatic driving. 3. The driving by pneumatic pressure is performed for each mechanism.
The in-circuit tester according to claim 1, wherein the test is performed using one air cylinder, and when the positioning or the clamping is completed, the test circuit board is pressed by a predetermined spring force of a predetermined spring. . 4. The test pin position correction is performed using a reference board having the same board shape as the test circuit board and having at least the first and second holes and at least two predetermined positions. 4. The in-circuit tester according to claim 1, wherein the positions of the two points are detected by the test pins, and the coordinate system of the XY stage mechanism is corrected based on the detected positions. . 5. The position of each of the two points is a center position of a circle, the reference board has an annular conductor film for each center of the circle, and the test pin is used to form the annular conductor film. A continuity check is performed for each predetermined distance unit from each of at least three locations, a center of the circle is obtained based on at least three continuity positions, and a reference origin of the test circuit board is set. Item 5. An in-circuit tester according to item 4. 6. The probe up-and-down mechanism moves the test pin up and down by a cross-slider crank mechanism that converts a rotary motion into a linear motion, and performs a soft landing on the test circuit board. The in-circuit tester according to claim 1, 2, 3, 4 or 5. 7. The soft landing according to claim 6, further comprising decelerating the rotational motion near the bottom dead center and near the top dead center where the test pin contacts the test circuit board. In-circuit tester. 8. The test pin has a predetermined inclination with respect to the Z-axis direction, and when the test pin contacts the test circuit board at a position higher than a reference surface of the test circuit board, 4. The test pin according to claim 1, wherein the test pin is moved up and down and rotated in response to the force applied to the test pin, and the tip of the test pin is moved in the Z direction while being in contact with the test circuit board. 8. The in-circuit tester according to 4, 5, 6, 6 or 7. 9. The test pin has a groove cut out along a circumferential direction of the test pin facing the test circuit board and along an axial direction of the test pin, and
9. A guide member which contacts the test pin at three points in a cross section perpendicular to the axis of the test pin, the guide member being guided by a guide member.
The in-circuit tester according to 1. 10. The test pin according to claim 1, wherein the test pin is rotatable by 90 degrees about a predetermined Z axis.
The in-circuit tester according to 2, 3, 4, 5, 6, 7, 8, or 9.