JP3075423B2 - In-circuit tester with two or three sets of XY unit arm movement controllers - 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 provided with two or three sets of XY units for use in judging the quality of a mounting board, and more particularly to an arm movement control device for each.

[0002]

2. Description of the Related Art Conventionally, a mounting board, that is, a printed board on which a large number of electric components are soldered, uses an in-circuit tester to appropriately contact probe pins to required measuring points on the board, and The quality of the substrate is determined by electrical measurement. In particular, the one in which the XY unit is installed on the measuring table on which the substrate to be inspected is mounted is provided with a Z-axis unit movable in the Y-axis direction on the arm movable in the X-axis direction, and the Z-axis unit is Since the probe pins are movably supported in the Z-axis direction, when the XY unit is controlled, the probe pins are moved from above the substrate to the X-axis and Y-axis.
By appropriately moving in the axis and Z-axis directions, it is possible to sequentially make contact with preset measurement points. A servomotor is used for the reciprocation of the arm in the X-axis direction and the reciprocation of the Z-axis unit in the Y-axis direction. An air cylinder is used for the reciprocation of the probe pin in the Z-axis unit in the Z-axis direction. Uses solenoids, servomotors, etc.

However, for that purpose, the XY coordinate data of each measurement point on the substrate to be inspected must be detected in advance. Therefore, in general, by manually teaching the probe pins of the XY unit,
Or using a digitizer that is a coordinate reading device or C
The XY coordinate data of each measurement point is obtained using the AD data. In order to shorten the inspection time per one substrate to be inspected, the inspection order of each measurement point to be brought into contact with the probe pin is set, and the moving speed and acceleration between each measurement point according to the order are set. There must be. This is because when the number of parts per sheet increases to about 1000, most of the inspection time is spent for moving the probe pins.

At the time of measurement, a plurality of measurement points must be measured simultaneously for each part. For example, when the resistance is measured, a guarding measurement point is specified as necessary together with a high-potential-side measurement point and an earth-side measurement point.
Therefore, the in-circuit tester needs to include a plurality of XY units.

When these XY units are controlled to move each probe pin simultaneously from the measured measurement point to the next measurement point, the speed and acceleration of each arm in the X-axis direction and each A method in which the velocity and acceleration of the Z-axis unit in the Y-axis direction are set to the same constant value and moved, and after the movement of each arm is completed, only each Z-axis unit is further moved (each probe pin does not move linearly); A method of setting the speed and acceleration in the X-axis direction of each arm and the speed and acceleration in the Y-axis direction of each Z-axis unit so that each probe pin moves linearly (two-dimensional linear interpolation method), each probe The speed and acceleration in the X-axis direction of each arm and each Z are set so that the pin moves linearly and the movement time of each arm becomes the same.
There is a method (n-dimensional linear interpolation method) for setting the speed and acceleration of the axis unit in the Y-axis direction.

[0006]

However, with these moving methods, for example, a parallel movement in which the X coordinate of each measurement point at the start of movement is the same and the X coordinate of each measurement point at the end of movement is the same is considered. If the moving speed and acceleration of each probe pin are increased, a collision due to catch-up between the arms becomes a problem. This is because each X-axis motor and motor driver have a variation in response time constant, and each arm has a response change due to variation in weight and friction coefficient, an error in calculating a set speed and acceleration, and the like. For this reason, when the speed and the acceleration are small, the respective arms normally move according to the theory and do not collide with each other in the above method, but in the method, the velocity in the X-axis direction changes, and there is a risk of collision. When the movement of each arm is started at the same time, such a force is applied to generate a large vibration in the frame, which has a problem that each member of the apparatus is adversely affected.

The present invention has been made in view of such a conventional problem, and in order to shorten the inspection time,
Even if the moving speed and acceleration of each arm are set to be large, no collision occurs between the arms due to catch-up, and two or three sets of durable in-circuit units having XY unit arm movement control devices. The purpose is to provide a tester.

[0008]

Means for achieving the above object will be described below with reference to FIGS. The in-circuit tester provided with the two sets of XY unit arm movement control devices includes an XY unit 12 having a left arm 24 and an X circuit having a right arm 46.
Arm movement limiter 6 for installing Y unit 16 and preventing left arm 24 from moving beyond right arm 46;
8 and 74, arm movement start delay time setting means 96 for setting the waiting time of the following arm with respect to the preceding arm when the movement of both the left and right arms 24 and 46 starts, and along the X-axis. The arm moving direction determining means 98 for determining the moving direction of each of the left and right arms 24 and 46, and when both the left and right arms 24 and 46 move to the left, the moving order is set to the left arm 24, right When the left and right arms 24 and 46 move in opposite directions, the moving order is determined arbitrarily or simultaneously, and both the left and right arms 24 and 46 are moved to the right. When moving to the left arm, the arm moving order determining means 100 for determining the moving order in the order of the right arm 46 and the left arm 24; Those comprising an arm movement controller 104 of the motor control unit 102 which controls the X-axis motor 20, 38 which correspond in accordance with the movement order of the arms 24, 46 bets.

Further, the in-circuit tester provided with three sets of XY unit arm movement control devices further installs the XY unit 14 provided with the middle arm 44, and moves the left arm 24 beyond the middle arm 44. Arm movement restrictors 68 and 74 for preventing the right arm 46 from moving beyond the middle arm 44, and the left, middle and right arms 24, 4
Arm movement start delay time setting means 106 for setting the waiting time of the immediately succeeding arm with respect to the preceding arm at the time of starting movement of the arms 4 and 46, and an arm for determining the movement direction of the left and right arms 24 and 46 along the X axis When both the moving direction determining means 108 and the left and right arms 24 and 46 move to the left, the moving order is determined by the left arm 2
4, the middle arm 44 and the right arm 46 are determined in this order. When the left arm 24 moves to the left and the right arm 46 moves to the right, the middle arm 44 is determined at the end of the moving order, The arm 24 moves to the right,
When the right arm 46 moves to the left, the middle arm 44 is determined first in the moving order. When both the left and right arms 24 and 46 move to the right, the moving order is set to the right arm 46, Arm movement order determining means 110 for determining the order of the left arm 24, and the set waiting time and the determined left, middle and right arms 24, 44, 4
6 correspond to the X-axis motors 2 in accordance with the movement order.
An arm movement control device 114 including a motor control means 112 for controlling 0, 36 and 38 is provided.

[0010]

The speed and acceleration of each of the left and right arms 24 and 46 are set to be large as described above. Then, when both the arms 24 and 46 move to the left, the movement of the left arm 24 that should be on the front side starts first,
Since the movement of the light arm 46 is started after the elapse of the waiting time, the following arm 46 does not catch up with the preceding arm 24 and collide. Also, when both arms 24 and 46 move to the right, only the movement order is reversed, and a rear-end collision does not occur because a waiting time is interposed. At that time, both arms 2
Since the movement start times of the movements 4 and 46 are shifted, these forces cancel each other to some extent and are applied to the frame, so that the generated vibration is reduced. When the frames 24 and 46 move in opposite directions, the rear-end collision does not occur even if the moving order is arbitrary or simultaneous.

Further, the one to which the middle arm 44 is added operates in substantially the same manner, and both the left and right arms 24, 4
When both move leftward, the left arm 24, which should be the foremost first, then the middle arm 44, and finally the right arm 46, start to move with a waiting time interposed therebetween. The middle arm 44 in the immediately succeeding row against the 24 and the right arm 46 in the immediately succeeding row against the preceding middle arm 44 do not collide with each other. Also, both left and right arms 24,
When both 46 move to the right, only the order of movement is reversed, and a rear-end collision does not occur because of the waiting time. At this time, since the movement start time of each of the arms 24, 44, and 46 is shifted, the generated vibration is also reduced. When the left and right arms 24 and 46 move in directions opposite to each other, no rear collision occurs between the two arms 24 and 46. Then, finally, the movement of the middle arm 44 is started in accordance with the movement direction of the arms 24, 46,
Alternatively, if the movement of the middle arm 44 is first started, a collision does not occur because the waiting time is interposed.

[0012]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 3 is a plan view showing an arrangement relationship of the in-circuit tester having three sets of XY units to which the present invention is applied on a measuring table on which a substrate to be inspected is installed. In the figure, 1
0 is the measuring table of the in-circuit tester, 12, 14, 16
Is an XY unit of three sets installed on the upper part, and 18 is a board to be inspected installed in the center.

The XY unit 12 includes an X-axis servomotor 20 mounted on the measuring table 10, a ball screw 22 rotated by the motor 20, an arm 24 that moves in the X-axis direction by the rotation of the ball screw 22, A servomotor 26 for Y-axis mounted on the arm 24, a ball screw 28 rotated by the motor 26, and a Z-axis unit 30 that moves in the Y-axis direction by the rotation of the ball screw 28, Is provided with a probe pin 34 that is moved in the Z-axis direction by the Z-axis servo motor 32. Other XY
The units 14 and 16 have the same structure, respectively, and include the X-axis servo motors 36 and 38, the ball screws 40 and 42, the arms 44 and 46, the Y-axis servo motors 48 and 50, the ball screws 52 and 54, and the Z-axis. Units 56 and 58, Z-axis servo motors 60 and 62, probe pins 64 and 66, and the like. The X-axis servo motors 20, 36, 38
And the ball screws 22, 40, and 42 are separate, but are represented as the same in the drawings.

Then, each of the left and middle arms 24,
A pair of photocouplers 68 and light blocking pieces 70 are respectively installed as optical switches at 44, and similar photocouplers 72 and light blocking pieces 74 are respectively installed at the middle and light arms 44 and 46. Therefore, when these optical switches are used as arm movement restrictors, it is possible to prevent the left arm 24 from moving beyond the middle arm 44 and to prevent the right arm 46 from moving beyond the middle arm 44. Can also.

FIG. 4 is a block diagram showing the configuration of such an in-circuit tester having three sets of XY units. In the figure, 76 is an in-circuit tester, 78 is its operation unit, 80 is an XYZ control unit, 82 is a measurement unit, 84
Is a controller. The operation unit 78 includes input / output devices such as a keyboard, a display device, a printer, and a floppy disk driver. The XYZ controller 80 drives the servomotors 20, 26, 32 and the like provided in the three sets of XY units 12, 14, 16 respectively, and puts the respective probe pins 34, 64, 66 on the measuring table 10. To move as appropriate in the X-axis, Y-axis, and Z-axis directions. The measuring unit 82 transmits appropriate voltage and current signals to each of the probe pins 34 and 6 through the switch.
4 and 66 to measure each component.

The operation unit 78 and the XYZ control unit 8
The measuring unit 82 is controlled by a controller 84 having a CPU. The controller 84 is shown in FIG.
And a CPU (Central Processing Unit) 86, a ROM (Read Only Memory) 8
8, a RAM (read / write memory) 90, an input / output port 92, a bus line 94, and the like.
The CPU 86 corresponds to the brain part which is the center of the microcomputer, executes control of the whole according to the instructions of the program, performs arithmetic and logical operations, and temporarily stores the results. Also, control is appropriately performed on peripheral devices. The ROM 88 stores a control program and the like for controlling the entire in-circuit tester. The RAM 90 stores various data such as data input from the outside, data measured using the probe pins 34, 64, and 66, and data calculated by the CPU 86 from the data. At that time, the XY coordinate data of each measurement point existing on the inspection target board 18 is stored in each probe pin 34,
64 and 66 are manually operated and read directly by teaching, or stored on a floppy disk using a digitizer and then input from the outside. Moreover,
The three measurement points corresponding to each part are grouped as one step, and they are sequentially numbered and stored.
Further, an arm movement control processing program and the like are also input from outside. An operation unit 78, an XYZ control unit 80, a measurement unit 82, and the like are connected to the input / output port 92. The bus line 94 includes an address bus line, a data bus line, a control bus line, and the like for connecting them, and is appropriately connected to a peripheral device.

FIG. 6 is a flowchart showing the operation of the in-circuit tester having three sets of XY units according to the arm movement control processing program, which is executed by the respective processes P1 to P9. First, a wait time is set in the order of, for example, 1/1000 second during a movement start time of each of the left, middle, and right arms 24, 44, and 46 by a key operation at P1. However, the upper limit of the waiting time is set sufficiently smaller than the traveling time. The speed, acceleration of each of the left, middle, and right arms 24, 44, and 46 is set to be large first. Next, the process proceeds to P2, and it is determined whether the left arm 24 is to be moved to the left. If YES, go to P3. At P3, it is determined whether the light arm 46 is to be moved to the left. If YES, go to P4.

At P4, the moving order is determined in the order of the left arm 24, the middle arm 44, and the right arm 46. When both the left and right arms 24, 46 move to the left in this way, as shown in FIG. 7, the left arm 24, which should be the foremost first, then the middle arm 44, and finally the right arm 46 If the movements are started sequentially while interposing the waiting time t0 in sequence, the speed and acceleration relation for the same movement time of each arm 24, 44, 46 does not change. However, the right arm 46 immediately following the middle arm 44 catches up with the preceding middle arm 44 and does not collide. At this time, the movement start times of the arms 24, 44, and 46 are sequentially shifted by the waiting time t0, so that the forces cancel each other to some extent and are applied to the frame, so that the generated vibration is reduced.

If the answer is NO in P3, the program goes to P5. In P5, the moving order is determined in the order of the left arm 24, the right arm 46, and the middle arm 44. In this way, when the left arm 24 moves to the left and the right arm 46 moves to the right, if the movement of the middle arm 44 is started last, a waiting time is interposed, and no rear-end collision occurs.
Since the left and right arms 24 and 46 move in opposite directions, the rear-end collision does not occur between the two arms. Therefore, the order of movement may be reversed or the movement may be started at the same time. .

If P2 is NO, the program goes to P6. In P6, it is determined whether the light arm 46 moves to the left. If YES, go to P7. In P7, the moving order is the middle arm 44, the right arm 46, the left arm 2
4 is determined in order. In this way, when the left arm 24 moves rightward and the right arm 46 moves leftward, if the movement of the middle arm 44 starts first, a rear-end collision does not occur because of the waiting time. If the left and right arms 24 and 46 move in directions opposite to each other, there is no danger of rear-end collision. Therefore, the order of movement may be reversed or movement may be started at the same time.

If the answer is NO in P6, the program goes to P8. In P8, the moving order is determined in the order of the right arm 46, the middle arm 44, and the left arm 24. When both the left and right arms 24, 46 move to the right in this way, a waiting time is interposed in the order of the right arm 46, which should be the first, the middle arm 44, and finally the left arm 24. Since the movement starts sequentially, no rear-end collision occurs.

After the processing of each of P4, P5, P7 and P8, P
Go to 9. At P9, according to the set waiting time and the determined moving order of the left, middle, and right arms 24, 44, 46, the corresponding X-axis motors 20, 3 respectively.
6, 38 are controlled. The motors 20, 3
Signals are input to 6 and 38 via driving drivers, respectively.

Further, each of the Y-axis motors 26, 48, 50 is controlled, and each probe pin 34, 64, 66 is moved to a corresponding measurement point. Then, the respective Z-axis motors 32, 60, 62 are controlled, respectively, and the respective probe pins 34, 64, 66 are respectively brought into contact with the measurement points. Thus, a measurement current is applied to the component or a measurement voltage is applied to the component via each of the probe pins 34, 64, and 66 to measure a resistance value, a capacitance value, an inductance value, and the like. In this way, by repeating the measurement of each component while moving each of the probe pins 34, 64, 66, the quality of the board to be inspected 18 can be determined.

FIG. 8 is a flowchart showing the operation of the in-circuit tester having two sets of XY units according to the arm movement control processing program, which is executed by the respective processes P11 to P19. In this case, since there is no equivalent to the XY unit 14 having the middle arm 44 in the above embodiment, the XY unit having the left arm 24 is not provided.
Only the operation of the XY unit 16 including the unit 12 and the light arm 46 needs to be considered. The optical switch including the photocoupler 68 provided on the left arm 24 and the light blocking piece 74 provided on the right arm 46 is a left arm 2
4 acts as an arm movement limiter that prevents movement beyond the right arm 46. Therefore, at P11, the waiting time of the following arm with respect to the preceding arm at the start of the movement of both the left and right arms 24 and 46 is set. And
At P12, P13, and P16, determination processing of the moving direction of each of the left and right arms 24 and 46 is performed in the same manner.

However, in P14, the moving order is determined in the order of the left arm 24 and the right arm 46. When both the arms 24 and 46 move to the left in this way, the movement of the left arm 24 which should be on the front side starts first, and the movement of the right arm 46 starts after the elapse of the waiting time. There is no collision of the trailing arm 46 with the trailing arm 46. At that time, since the movement start time of the arms 24 and 46 is shifted, the generated vibration is also reduced.

At P15, the moving order is determined in the order of the left arm 24 and the right arm 46. In P17, the moving order is determined in the order of the right arm 46 and the left arm 24. When the two arms 24 and 46 move in the opposite directions as described above, the rear-end collision does not occur even if the moving order is arbitrary or simultaneous.

At P18, the moving order is determined in the order of the right arm 46 and the left arm 24. Thus, both arms 2
When both 4 and 46 move to the right, the movement of the right arm 46 that should be on the front side starts first, and the movement of the left arm 24 starts after the elapse of the waiting time, so that no rear-end collision occurs.

After the processing of each of P14, P15, P17 and P18, the process goes to P19. In P19, the corresponding X-axis motors 20 and 38 are controlled in accordance with the set waiting time and the determined moving order of the left and right arms 24 and 46, respectively.

[0029]

According to the present invention described above, the speed and acceleration of each arm can be set large to shorten the inspection time. Then, a waiting time is interposed between the movement start times of the arms moving in the same direction, and the arms start moving in order from the arm that should be on the front side, so that no collision occurs between the arms. Also, if the movement start time of each arm is shifted,
Since the forces cancel each other and are applied to the frame, the generated vibration is reduced and the durability of the device is improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing an in-circuit tester provided with two sets of XY unit arm movement control devices according to the present invention.

FIG. 2 is a view showing an in-circuit tester provided with three sets of XY unit arm movement control devices according to the present invention.

FIG. 3 is a plan view showing an arrangement relationship of an in-circuit tester having three sets of XY units to which the present invention is applied on a measuring table on which a substrate to be inspected is installed.

FIG. 4 is a block diagram showing a configuration of the in-circuit tester.

FIG. 5 is a block diagram showing a controller of the in-circuit tester.

FIG. 6 is a flowchart showing an operation of the in-circuit tester according to an arm movement control processing program.

FIG. 7 shows the speed of arm movement of the in-circuit tester,
It is a figure which shows an acceleration and time relationship.

FIG. 8 is a flowchart showing an operation of an in-circuit tester having two sets of XY units according to an arm movement control processing program.

[Explanation of symbols]

10 measuring table 12, 14, 16 ... XY unit 1
8 ... Substrate to be inspected 20, 36, 38 ... X axis motor 2
2, 28, 40, 42, 52, 54 ... ball screw 24,
44, 46: Left, middle, right arm 26, 4
8, 50: Y-axis motor 30, 56, 58 ... Z-axis unit 32, 60, 62 ... Z-axis motor 34, 64,
66 ... probe pins 68, 70, 72, 74 ... arm movement limiter 76 ... in-circuit tester 78 ... operation unit 80 ... XYZ control unit 82 ... measurement unit 84 ... controllers 96 and 106 ... arm movement start delay time Setting means 98, 108 ... arm moving direction determination means 100,
110: arm movement order determination means 102, 112 ... motor control means 104, 114 ... arm movement control device

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G01R 31/28 G01R 1/06 G01R 31/02

Claims (2)

(57) [Claims] 1. An in-circuit tester having an XY unit having a left arm and an XY unit having a right arm, and having an arm movement limiter for preventing the left arm from moving beyond the right arm. Arm movement start delay time setting means for setting the waiting time of the following arm with respect to the preceding arm at the start of movement of both the left and right arms, and determining the movement direction of each of the left and right arms along the X axis When both the left and right arms are moved to the left, the moving order is determined in the order of the left arm and the right arm, and both the left and right arms move in opposite directions. , Determine the order of movement in any order or simultaneously,
When both the left and right arms move to the right, the arm movement order determining means determines the order of movement in the order of the right arm and the left arm, and the movement of each of the left and right arms determined with the set waiting time. An in-circuit tester comprising two sets of XY unit arm movement control devices, comprising: an arm movement control device comprising: a motor control means for controlling a corresponding X-axis motor in order. 2. An XY unit with a left arm, an XY unit with a middle arm, and an XY unit with a right arm are installed to prevent the left arm from moving beyond the middle arm. In an in-circuit tester provided with an arm movement limiter for preventing movement of the right arm beyond the middle arm, the left,
Arm movement start delay time setting means for setting the waiting time of the immediately succeeding arm with respect to the preceding arm at the start of movement of each of the middle and right arms, and arm movement for determining the movement direction of each of the left and right arms along the X axis. When the direction determination means and both the left and right arms move to the left, the moving order is determined in the order of the left arm, the middle arm, and the right arm, and the left arm moves to the left,
When the right arm moves to the right, the middle arm is determined at the end of the moving order, the left arm moves to the right,
If the right arm moves to the left, the middle arm is determined at the beginning of the movement order.If both the left and right arms move to the right, the movement order is set to right arm, middle arm, and left arm. An arm movement control device comprising: arm movement order determination means for determining the order; and motor control means for controlling the corresponding X-axis motors in accordance with the set waiting time and the determined movement order of the left, middle, and right arms. Three sets of X-
An in-circuit tester equipped with a Y unit arm movement control device.