JP3075422B2 - 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 electrical components are soldered, uses an in-circuit tester to appropriately contact probe pins to required measurement points on the board, and the electrical power of each of those components is measured. The quality of the substrate is determined by objective 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.

The present invention has been made in view of such a conventional problem, and in order to shorten the inspection time,
It is an object of the present invention to provide an in-circuit tester including two or three sets of XY unit arm movement control devices in which a collision due to catch-up between arms does not occur even if the movement speed and acceleration of each arm are set large. And

[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;
Arm constant for setting the operation constant for changing the speed and acceleration of each of the left and right arms 24 and 46 from the previously set reference value; An arm moving direction determining means 98 for determining the moving direction of each of the left and right arms 24 and 46 along the X axis, and an arithmetic constant when both the left and right arms 24 and 46 move to the left. When the speed and acceleration of the left arm 24 are increased from the reference value or the speed and acceleration of the right arm 46 are decreased from the reference value, and both the left and right arms 24 and 46 move to the right, the operation constant is calculated. Means for decreasing the speed and acceleration of the left arm 24 from the reference value or increasing the speed and acceleration of the right arm 46 from the reference value by using The left, each of the light arm 2
Motor control means 10 for controlling the corresponding X-axis motors 20 and 38 based on the speeds and accelerations 4 and 46, respectively.
2 is provided.

The in-circuit tester provided with three sets of XY unit arm movement control devices further includes an XY unit 14 provided with a middle arm 44, and moves the left arm 24 beyond the middle arm 44. Movement limiters 68, 70, 72, 74 for preventing the light arm 46 from moving beyond the middle arm 44.
And arm speed and acceleration variable operation constant setting means 106 for setting operation constants for changing the speed and acceleration of each of the left, middle and right arms 24, 44 and 46 from the previously set reference values. Moving direction determining means 108 for determining the moving direction of each of the left and right arms 24 and 46 along the X-axis, and both the left and right arms 2
When both 4 and 46 move to the left, the speed and acceleration of the left arm 24 are increased from the reference value using the arithmetic constants, and the speed and acceleration of the right arm 46 are decreased from the reference value. Moves to the left and the right arm 46 moves to the right, the speed and acceleration of each of the left and right arms 24 and 46 are respectively increased from the reference values using the operation constants, and both the left and right arms are used. Arm 2
When both 4 and 46 move to the right, the speed and acceleration of the left arm 24 are reduced from the reference values using the arithmetic constants, and the speed and acceleration of the right arm 46 are increased from the reference values. When the right arm 46 moves to the right and the right arm 46 moves to the left, an arm speed and acceleration variable means 110 for increasing the speed and acceleration of the middle arm 44 from a reference value using the operation constants,
Based on the speed and acceleration of each of the middle and light arms 24, 44, 46, the corresponding X-axis motor 20,
An arm movement control device 114 comprising a motor control means 112 for controlling 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 reference values first. Then, by performing addition, subtraction, multiplication, and division with respect to the reference value using the operation constant, when both arms 24 and 46 move in the same direction to the left or right, the left arm 24 or the right arm 46 that should be on the front side Light arm 4 to increase the speed and acceleration from the reference value or to be on the rear side
6 or the speed and acceleration of the left arm 24 are reduced from the reference values.
Or 46 does not catch up with the rear arm 46 or 24.

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
In the case where 6 moves in the same direction to the left or right, the speed and acceleration of the left arm 24 or the right arm 46 to be on the front side are increased from the reference values, and the right arm 46 or the left arm to be on the rear side. Since the speed and acceleration of the arm 24 are reduced from the reference values, each arm 24, 4
4 and 46, the front arm 24 or 46
The middle arm 44 catches up with the middle arm 44
The rear arm 46 or 24 does not catch up with and collide with the rear arm. When the left arm 24 moves to the left and the right arm 46 moves to the right, the speed and acceleration of each of the left and right arms 24 and 46 are respectively increased from the reference values. It does not catch up with the left arm 24 or the right arm 46 and collide.
Further, when the left arm 24 moves to the right and the right arm 46 moves to the left, the speed and acceleration of the middle arm 44 increase from the reference values.
4 does not catch up with the left arm 24 or the right arm 46.

[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, at P1, an operation constant for changing the speed and acceleration of each of the left, middle and right arms 24, 44 and 46 from the previously set reference value is set as + C% or -C% by key operation. 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. Y
In the case of ES, go to P3. Light arm 46 in P3
Is determined to move to the left. If YES, go to P4.

In P4, the speed and acceleration of the left arm 24 are increased from the reference value, and the speed and acceleration of the right arm 46 are decreased from the reference value by appropriately performing addition, subtraction, multiplication and division on the reference value using the operation constant. . FIG.
Shows the relationship between the movement speed v, the movement acceleration θ, and the movement time t of the arm for the reference value A, B when the speed and acceleration are increased, and C when the speed and acceleration are reduced, respectively. Then, the speed and acceleration of the middle arm 44 remain unchanged at the reference values. For this reason, even if the movement of each of the arms 24, 44, and 46 is started at the same time, the middle arm 44 does not catch up with the left arm 24 or the right arm 46 catches up with the middle arm 44 and does not collide.

If the answer is NO in P3, the program goes to P5. In P5, the speed and acceleration of each of the left and right arms 24 and 46 are increased from the reference values using the operation constants. Then, the speed and acceleration of the middle arm 44 are not changed while keeping the reference values. Therefore, the middle arm 44 does not catch up with and collide with the left arm 24 or the right arm 46.

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. At P7, the speed and acceleration of the middle arm 44 are increased from the reference values using the operation constants. Then, the left and right arms 24, 4
The speed and acceleration of No. 6 remain unchanged at the reference values. Therefore, the left arm 24 or the right arm 46 does not catch up with and hit the middle arm 44.

If the answer is NO in P6, the program goes to P8. At P8, the speed and acceleration of the left arm 24 are reduced from the reference values using the operation constants, and the speed and acceleration of the right arm 46 are increased from the reference values. Then, the speed and acceleration of the middle arm 44 are not changed while keeping the reference values. Therefore, the left arm 24 does not catch up with the middle arm 44 or the middle arm 44 catches up with the right arm 46 and does not collide.

After the processing of each of P4, P5, P7 and P8, P
Go to 9. At P9, based on the determined speeds and accelerations of the left, middle and right arms 24, 44 and 46,
The corresponding X-axis motors 20, 36, 38 are controlled. The motors 20, 36, and 38 receive signals via driving drivers.

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, in P11, an operation constant for changing the speed and acceleration of each of the left and right arms 24 and 46 from the previously set reference values is set. And P1
2, left and right arms 2 on P13 and P16
The processing for determining the moving direction in steps 4 and 46 is performed in the same manner.

However, in P14, the speed and acceleration of the left arm 24 are increased from the reference values or the speed and acceleration of the right arm 46 are decreased from the reference values by using the operation constants. Therefore, even if the movements of the arms 24 and 46 are started simultaneously, the right arm 46 does not catch up with and collide with the left arm 24.

In P15 and P17, the speed and acceleration of each of the left and right arms 24 and 46 are not changed from the reference values. In P15, the left and right arms 24,
Even if 46 moves in the opposite direction, there is no danger of collision at all, so that the speed and acceleration thereof can be respectively increased from the reference values.

At P18, the speed and acceleration of the left arm 24 are reduced from the reference values using the operation constants, or the speed and acceleration of the right arm 46 are increased from the reference values. Therefore, the left arm 24 does not catch up with the right arm 46 and collide.

After the processing of each of P14, P15, P17 and P18, the process goes to P19. At P19, the corresponding X-axis motors 20 and 38 are controlled based on the determined speed and acceleration of each of the left and right arms 24 and 46.

[0029]

According to the present invention described above, since the speed and acceleration of each arm are set large and set as reference values, the inspection time can be shortened. Then, since the speed and acceleration of the arm to be moved to the same side in the same direction are increased from the reference value, or the speed and acceleration of the arm to be moved to the rear side are decreased from the reference value, no rear-end collision occurs.

[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 speed and acceleration variable Calculation constant setting means 98, 108 ... arm moving direction determining means 100, 110 ... arm speed and acceleration varying means 10
2, 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 speed / acceleration operation constant setting means for setting an operation constant for changing the speed and acceleration of each of the left and right arms from the previously set reference value, and movement of each left and right arm along the X axis Arm moving direction determining means for determining the direction, and when both the left and right arms move to the left, the arithmetic operation constant is used to increase the speed and acceleration of the left arm from a reference value, or the speed of the right arm, When the acceleration is reduced from the reference value and both the left and right arms move to the right, the speed and acceleration of the left arm are calculated using the calculation constants. Arm speed that decreases the reference arm or increases the speed and acceleration of the light arm from the reference value,
Two sets including an arm movement control device including acceleration variable means and motor control means for controlling a corresponding X-axis motor based on the determined speed and acceleration of each of the left and right arms. The in-circuit tester provided with the XY unit arm movement control device of FIG. 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 speed and calculation constant setting means for changing the speed and acceleration of each arm of the middle and the right from the previously set reference value, and an arithmetic constant setting means for varying the acceleration, and the moving direction of each arm of the left and the right along the X axis. When both the left and right arms move to the left, the speed and acceleration of the left arm are increased from a reference value by using an arithmetic constant, and the speed and acceleration of the right arm are determined. When the left arm moves to the left and the right arm moves to the right, the speed and acceleration of each arm of the left and right arms are increased using arithmetic constants from the reference values, respectively. When both the left and right arms move to the right, the speed and acceleration of the left arm are reduced from the reference values using the arithmetic constants, When the speed increases from the reference value, the left arm moves to the right, and the right arm moves to the left, the arm speed and acceleration that increase the speed and acceleration of the middle arm from the reference value using arithmetic constants are used. Means,
An arm movement control device comprising: a motor control unit that controls a corresponding X-axis motor based on the determined speed, acceleration of each of the left, middle, and right arms. An in-circuit tester equipped with a Y unit arm movement control device.