JPH1058286A - Locating method and device for work to be processed - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the working period by placing a work to be processed on a table, conducting correction of its positioning quickly, and eliminating the waiting time till the next stage of the processes. SOLUTION: A work to be processed 11 is placed on a table 12, and setting is made so that the work 11 faces a specified direction and takes the specified positioning. In this work locating method, the work 11 is provided with locating marks 11a and 11b and reference marks 12a and 12b are provided on the table 12 in its two places close to the locating marks 11a and 11b, and the coordinates for the closely positioned set of reference marks and locating marks are read simultaneously, followed by simultaneous reading of the coordinates for the other set, and from the acquired data, acknowledgement is made for the position of the work 11 with respect to the reference marks 12a and 12b on the table 12, and thus the location of the work 11 is conducted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for high-speed positioning of a workpiece on which the surface of an object is subjected to processing such as printing. More specifically, the present invention relates to a method and an apparatus for positioning a workpiece which can immediately recognize the position of the workpiece by image recognition and correct the position after the workpiece is placed on a worktable.

[0002]

2. Description of the Related Art Conventionally, when a square chip resistor or the like is manufactured, as shown in FIG. 2A, a work 11 such as an MCR sheet is x-θ at a work (workpiece) supply section A. It is placed on the table 12 by a vacuum suction method or the like. The x-θ table 12 can be rotated around its axis and adjusted in its x direction (direction of a one-axis table).
Fine adjustment is also possible, and furthermore, it can be moved back and forth on the uniaxial table 13 at a fixed distance. The x-θ table 12 on which the work 11 is placed is
After being moved on the axis table 13 and sent to the image processing unit B, the camera 14 recognizes the position of the workpiece 11 with respect to the one-axis table 13. As shown in FIG. 2B, the work 11 is provided with positioning marks (holes) 11a and 11b, and the position of the work 11 is determined by recognizing the coordinates of the positioning marks 11a and 11b by the camera 14. recognize. Based on the recognized position of the work 11, the image processing device 15 calculates the rotation angle of the x-θ table 12 and the correction amount in the x direction, and corrects the position of the x-θ table 12.

After that, the x-θ table 12 is further moved in the x direction by a fixed amount to advance to the processing section C, where processing such as sequential printing of a resistor, glass, and electrode material is performed. Thereafter, the x-θ table 12 advances to the unloading section at the end of the one-axis table 13, and the work 11
It is lowered from the table 12. And x-θ table 1
2 also returns to the original work supply section A on the one-axis table 13, repeats the same work, and the work is automatically performed one after another.

Such a work is not limited to the printing of a rectangular chip resistor, but may be performed when a work is automatically placed on a table and processed on a surface thereof, such as a print head or a multilayer ceramic capacitor. Similarly, after mounting on the table, the position is corrected, and then the processing operation is performed.

[0005]

In the conventional method of placing a workpiece (workpiece) on a table of this type and positioning the workpiece, and then performing the machining, it takes time to recognize the position of the workpiece. There is such a problem. That is, the position is recognized after the work is placed on the table and conveyed to the image processing unit B. However, since the conveyance to the image processing unit B is performed by the servomotor, the work reaches the image processing unit B. Also, it vibrates for a while, and the position coordinates of the positioning mark of the work cannot be recognized until the vibration stops. In addition, the camera is fixed to a rigid body so as not to vibrate. However, the vibration is transmitted when the workpiece is moved, and the camera also vibrates.
For this reason, the camera cannot recognize the positioning mark of the work unless the vibration of the table or the camera that conveys the work is settled, which is an obstacle to improving the work speed.

SUMMARY OF THE INVENTION The present invention solves such a problem, and a method for positioning a workpiece to quickly correct the position of the workpiece after placing the workpiece, eliminating a waiting time between processes and shortening a work period. And an apparatus thereof.

[0007]

According to the method for positioning a workpiece according to the present invention, the workpiece is placed on a table so that the workpiece can be processed in a certain direction. ,
A method of positioning a workpiece to be set at a fixed position, wherein a reference position mark is provided on a portion of the table adjacent to two locations of a positioning mark provided on the workpiece. Simultaneously reading the respective coordinates of the adjacent set of the reference position mark and the positioning mark, and simultaneously reading the respective coordinates of the other set, and processing the processed data for the reference position mark provided on the table from the read data. The position of the workpiece is recognized, and the workpiece is positioned. As a result, one set of the reference position mark of the table and the positioning mark of the workpiece can be read by the camera at the same time, and even if it vibrates, the reference position mark vibrates at the same time. It is possible to know the position of the positioning mark. By reading the coordinates of another set of reference position marks and positioning marks,
The position of the positioning mark of the workpiece relative to the two reference position marks can be known. On the other hand, since the position coordinates of the two reference position marks are known in advance, the absolute position coordinates of the positioning marks of the workpiece can be obtained. As a result, the rotation angle and the amount in the x direction to be corrected can be calculated, and the workpiece can be transferred to the processing section without waiting for the stop of the vibration.

According to the present invention, there is provided an apparatus for positioning a workpiece, wherein the table is rotatable around a central axis, the position of the table is corrected in at least one direction, and at least two of positioning marks provided on the workpiece are provided. First and second reference position marks are respectively provided on the table in a portion adjacent to each of the locations.

A table for supplying the workpiece;
The image processing unit that recognizes the position of the workpiece on the table for positioning and the processing unit that processes the workpiece are mounted on a table that can move at a fixed distance from each other. This is preferable because the position correction amount and the transport amount to the processing unit can be reliably maintained.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a workpiece positioning method and apparatus according to the present invention.

FIG. 1 is a perspective explanatory view of a table portion when a work as a workpiece is placed on a table for explaining the present invention. When the work (work) 11 is the above-described square chip resistor and the surface thereof is subjected to processing such as printing of a resistor, the table 12 is placed on the uniaxial table 13 as shown in FIG. And the reciprocating motion of the workpiece supply unit A, the image processing unit B, the processing unit C, and the unloading unit is the same. Note that the reciprocating table is not limited to the one-axis table.

According to the present invention, first and second reference position marks 12a and 12b are provided on the table 11 on which the work 11 is placed, at positions near the first and second positioning marks 11a and 11b of the work 11, respectively. It is characterized by having. That is, the work 1 is placed on the table 12.
When the work 1 is placed, the position of the work 11 is not fixed, but the work 11 does not vary everywhere on the table 12, but is placed near a certain place. Causes a displacement. Therefore, the positions of the first and second positioning marks 11a and 11b provided at a fixed location on the work 11 come to a substantially fixed location. Based on this rule of thumb, the first and second positioning marks 11a, 11b
The first and second reference position marks 12a and 12b are provided on the table 12 at a place close to the place and not hidden by the work 11, respectively. This reference position mark 12
a, 12b and positioning marks 11a, 11 of the workpiece 11
The distances from the camera 14 in the image processing unit B are
(See FIG. 2), both are observed at once, and the distance is set within a range in which the respective position coordinates can be recognized.

In the positioning method and apparatus according to the present invention, the reference position marks 12a and 12b are provided on the table 12 at a position close to the positioning marks 11a and 11b of the work 11 on the table 12 as described above. Therefore, when the camera recognizes the positioning marks 11a and 11b, the first positioning mark 11a and the first reference position mark 12a can be simultaneously put in the field of view of the camera, and the first positioning mark 11a Both coordinates of the first reference position mark 12a can be read simultaneously by the camera. As a result, even if the workpiece 11 is vibrating or the camera is vibrating, both marks 11
a, 12a vibrate in the same manner and are read simultaneously.
Therefore, even if absolute position coordinates cannot be known due to vibration, a relative positional relationship can be grasped from both coordinates.

In this case, the first reference position mark 12a is a fixed point on the table 12, and the position coordinates in a non-vibrating state are known, but the rotation angle is not known from only one point, and the first reference mark 11a Can not grasp the absolute position coordinates of. However, by measuring the second reference position mark 12b and the second positioning mark 11b in the same manner, the relative positional relationship of the second positioning mark 11b with respect to the second reference position mark 12b can be known. Therefore, the first reference position mark 12a
And the first reference mark 11a, the second reference position mark 12b, and the second reference mark 11b are read at the same time, respectively, to simultaneously measure the first and second reference position marks 12a, 12b. From the coordinates, it is possible to know the amount of deviation and inclination of the measurement coordinates in the x direction due to vibration with respect to the coordinates of the known first and second reference position marks 12a and 12b which are originally in a fixed direction.
By taking into account the amount of displacement and tilt in the x direction due to the vibration of the reference position marks 12a, 12b, the first and second positioning marks 11a, 11b are compared with the reference position marks 12a, 12b in a non-vibrating state. The amount of displacement and inclination in the x direction (positioning marks 11a, 11
b's absolute coordinates).

By correcting the position of the x-.theta. Table 12 in the x and .theta. Directions based on the amount of the deviation and the inclination in the x direction, the position of the work 11 can be accurately determined with respect to the direction of the one-axis table. Positioned. Then, the workpiece 11 is set in a fixed position at a fixed position by being conveyed to a processing unit, and processing such as printing of a resistor, glass, and an electrode is automatically performed. Although the shift amount in the y-direction can be recognized, there is no problem even if the position is not corrected in the y-direction because processing such as printing is performed along the y-direction. If it is necessary to adjust the position also in the y direction, the position in the y direction can be corrected by using an xy-θ table as the table 12.

[0016]

According to the present invention, as described above, the position coordinates of the positioning mark of the workpiece are measured simultaneously with the reference position mark provided in the x-.theta.
Since the measurement is performed in pairs, the measurement can be performed as a position relative to the reference position mark without waiting for the vibration of the x-θ table or the camera to stop. Therefore, immediately after the work is supplied to the x-θ table and conveyed to the image processing unit, the measurement of the position coordinates by the camera and the correction of the position can be easily performed by a command from the image processing apparatus. Therefore, it is not necessary to wait for the stop of the vibration when being conveyed to the image processing unit and measuring the position coordinates, the work can be advanced during the vibration, the work process time can be greatly reduced, and Tact time, which is a series of process times, can be reduced.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a relationship between a table and a workpiece used in a method and an apparatus of the present invention.

FIG. 2 is an explanatory diagram of a step of positioning a workpiece for conventional processing.

[Explanation of symbols]

 11 Workpiece 11a First positioning mark 11b Second positioning mark 12 Table 12a First reference position mark 12b Second reference position mark

Claims (3)

[Claims] In order to process a workpiece, the workpiece is placed on a table, and the workpiece is set in a certain direction and at a certain position. In a positioning method, a reference position mark is provided on a portion of the table adjacent to two positions of a positioning mark provided on the workpiece, and a reference pair of the reference position mark and the positioning mark is provided. The respective coordinates are read simultaneously, and then the respective coordinates of the other sets are read simultaneously. From the read data, the position of the workpiece with respect to the reference position mark provided on the table is recognized, and the positioning of the workpiece is performed. The method of positioning the workpiece to be performed. 2. In order to process a workpiece, the workpiece is placed on a table, and the workpiece is set in a certain direction and at a certain position. A positioning device, wherein the table is rotatable around a central axis, and its position can be corrected in at least one direction, and a portion close to each of at least two positions of positioning marks provided on the workpiece. A workpiece positioning device, wherein the table is provided with first and second reference position marks. 3. The apparatus according to claim 1, wherein the table includes a supply section for the workpiece, an image processing section for recognizing a position of the workpiece on the table for positioning, and a processing section for processing the workpiece. 3. The positioning device according to claim 2, wherein the positioning device is mounted on a table that can be moved at a fixed distance from each other.