JP3684944B2 - Work positioning device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a workpiece positioning device that positions electronic components such as a ceramic oscillator and a filter.
[0002]
[Prior art]
Conventionally, an automatic mounting machine that attaches electronic components (hereinafter referred to as a workpiece) such as a ceramic oscillator or a filter to a printed circuit board (hereinafter simply referred to as a substrate) has a positional accuracy when the workpiece is mounted on the substrate. In order to ensure, a method is employed in which a workpiece supplied to the main body by a linear feeder or the like is not directly mounted on the substrate, but after the workpiece is positioned by a pre-centering device, the workpiece is mounted on the substrate.
[0003]
FIG. 6 shows the concept of the electronic component mounting method in a general automatic mounting machine. In a general automatic mounting machine, a workpiece 21 supplied to a pickup unit 22 by a linear feeder or the like is sucked and held by a pickup nozzle 23 and placed on a stage 24 of a pre-centering device. Although the placement position of the workpiece 21 on the stage 24 is set in advance, the position accuracy of the workpiece 21 placed on the stage 24 is affected by the position accuracy of the workpiece 21 when supplied to the pickup unit 22. Was about ± 150 μm. In the case where high positional accuracy of ± 150 μm or more is required, the stage 24 is provided with a pre-centering device. The pre-centering device positions the workpiece 21 by moving the workpiece 21 placed on the stage 24 to a predetermined position (hereinafter referred to as a positioning position). A general pre-centering device can position the workpiece 21 with an accuracy of about ± 30 μm.
[0004]
Here, the pre-centering device will be described. FIG. 7 is a perspective view of a stage portion of a conventional pre-centering apparatus, and FIG. 8 is a plan view of the stage portion. The area surrounded by the first broken line shown in FIG. 8 is the placement position A, and the area surrounded by the second broken line shown in FIG. The pre-centering device moves the positioning claw 31 in the X and Y directions shown in the drawing, thereby pressing the workpiece 21 placed at the placement position A and moving it to the positioning position B, thereby positioning the workpiece 21. Is to do. Such a pre-centering device can position the workpiece 21 with respect to the positioning position B with an accuracy of about ± 30 μm. Then, returning to FIG. 6, the bonding nozzle 25 sucks and holds the workpiece 21 positioned at the positioning position B and mounts it on the substrate 26.
[0005]
Further, in the conventional pre-centering apparatus, when the bonding nozzle 25 sucks and holds the workpiece 21, the positioning position of the stage 24 is suppressed in order to prevent the positioned workpiece 21 from moving due to an impact or the like when contacting the bonding nozzle 25. A large number of holes 32 were formed in B, and the work 21 was sucked and held on the stage 24 by a suction pump (not shown). Thereby, the movement of the workpiece 21 due to an impact when the bonding nozzle 25 sucks and holds the workpiece 21 is suppressed, and the position accuracy of the workpiece 21 mounted on the substrate 26 is prevented from being lowered.
[0006]
[Problems to be solved by the invention]
However, since the conventional pre-centering apparatus only holds the workpiece 21 on the stage 24 at the positioning position B, the workpiece 21 placed on the placement position A by the pickup nozzle 23 is sucked on the stage 24. Did not hold. For this reason, the posture of the work 21 placed at the placement position A is not stable, and the trouble that the pre-centering device cannot be positioned due to the work 21 falling to the side or the like is high, resulting in high production efficiency. There was a problem of lowering.
[0007]
An object of the present invention is to provide a work positioning device that can improve the production efficiency by constantly stabilizing the posture of a work placed on a stage to suppress the frequency of occurrence of trouble such as the work falling sideways. It is to provide.
[0008]
[Means for Solving the Problems]
In order to solve the above-described problem, the workpiece positioning device of the present invention has the following configuration.
[0009]
(1) a stage for placing a workpiece supplied from outside;
In a workpiece positioning device comprising a positioning claw for sliding the workpiece on the stage and moving it to a predetermined position,
In the stage, a large number of holes are formed in an area including a placement position where the workpiece is placed and the predetermined position.
The hole formed in a predetermined position of the area and the hole formed in other positions are different in diameter,
A suction means for sucking and holding the workpiece on the stage using the plurality of holes is provided.
[0010]
In this configuration, the workpiece is positioned by moving the workpiece placed on the stage to a predetermined position by the positioning claw. In the stage, a large number of holes are formed in an area including a placement position where a workpiece is placed and a predetermined position. The suction means sucks and holds the workpiece on the stage using these many holes. As described above, since the workpiece placed at the placement position is also sucked and held on the stage, the posture of the workpiece placed on the stage can always be stabilized, and the workpiece is placed sideways. The frequency of troubles such as falling down can be suppressed. Thereby, production efficiency can be improved.
Further, since the diameters of the holes formed at the predetermined position and other positions of the stage are different, the suction force for attracting and holding the workpiece is different between the predetermined position and the other positions. Here, if the diameter of the hole formed at the predetermined position is made larger than the diameter of the hole formed at the other position, a vacuum leak in the stage can be suppressed when the workpiece is moved to the predetermined position. Therefore, the posture of the workpiece moved to the predetermined position can be further stabilized.
If the suction means for attracting and holding the workpiece on the stage is configured separately at the predetermined position and other positions, vacuum leakage at the stage when the workpiece is moved to the predetermined position can be suppressed, and the predetermined position can be obtained. The posture of the workpiece moved to the position can be made more stable.
[0015]
(2) The positioning claw has an opening.
[0016]
In this configuration, the opening formed in the positioning claw functions as a relief for the air being sucked. For this reason, after moving a workpiece | work to a predetermined position, the negative pressure which arises when retracting a positioning claw from this workpiece | work can be suppressed. Therefore, the movement of the work moved to the predetermined position by the negative pressure is suppressed, and the deterioration of the work positioning accuracy can be prevented.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a pre-centering device (work positioning device referred to in the present invention) which is an embodiment of the present invention will be described. The printing centering apparatus of this embodiment is also applied to the automatic mounting machine described in the section of “Prior Art”, and moves a workpiece placed on a stage to a predetermined position by a pickup nozzle. The apparatus for positioning the workpiece. As described above, the workpiece is supplied to the pickup unit by a linear feeder or the like, and the pickup nozzle sucks and holds the workpiece and places it on the stage of the pre-centering device. The position where the workpiece is placed on the stage is set in advance, and this position corresponds to the placement position referred to in the present invention.
[0018]
FIG. 1 is a perspective view showing a stage portion of a pre-centering apparatus according to an embodiment of the present invention, and FIG. 2 is a plan view of the stage portion of the pre-centering apparatus. In the figure, 1 is a stage on which a work is placed by a pickup nozzle (not shown), and 2 is a positioning claw for moving the work placed on the stage 1 to a predetermined position (hereinafter referred to as a positioning position). It is. A region A shown in FIG. 2 is a placement position A where a workpiece is placed by the pickup nozzle, and a region B is a positioning position B (a predetermined position referred to in the present invention) where the workpiece at the placement position A is moved and positioned. ). In the stage 1, a large number of holes 5 (5a, 5b) are formed at a constant pitch in an area including a placement position A where the workpiece is placed and a positioning position B where the workpiece is moved and positioned. Yes. The diameter of the hole 5a formed at the positioning position B is larger than the diameter of the hole 5b formed at other positions. The total area of the holes 5a formed in the stage 1 is larger than the total area of the holes 5b.
[0019]
The positioning claw 2 is configured to be movable in the X and Y directions shown in the figure, and moves the workpiece placed on the placement position A of the stage 1 to the positioning position B by moving in the X and Y directions. . The positioning claw 2 has an opening 6 formed therein. Further, a suction pump 10 that sucks air above the stage 1 using the holes 5 is provided.
[0020]
Hereinafter, the operation of the pre-centering apparatus of this embodiment will be described. A pickup nozzle (not shown) sucks and holds the workpiece 11 supplied to the pickup unit by a linear feeder or the like and places the workpiece 11 on the placement position A of the stage 1 (see FIG. 3A). At this time, since the suction pump 10 has already started suction, the workpiece 11 placed at the placement position A is sucked and held on the stage 1. Thereby, the attitude | position of the workpiece | work 11 mounted in the mounting position A can be stabilized, and generation | occurrence | production of troubles, such as this workpiece | work 11 falling sideways, is suppressed. When the workpiece 11 is placed at the placement position of the stage 1, the pre-centering device moves the positioning claw 2 by a predetermined amount in the Y direction (see FIG. 3B), and then further moves the positioning claw 2 in the X direction. Only a fixed amount is moved (see FIG. 3C). At this time, the positioning claw 2 presses the workpiece 11 placed at the placement position A of the stage 1 in the Y direction and the X direction, and moves the workpiece 11 to the positioning position B.
[0021]
All the holes 5a having a large diameter formed in the stage 1 are closed by the workpiece 11 moved to the positioning position B. The pre-centering device returns the positioning claw 2 to the original position (position shown in FIG. 3A) from the state shown in FIG. At this time, since the opening 6 formed in the positioning claw 2 functions as a relief of the air sucked by the suction pump 10, the negative pressure generated between the positioning claw 2 and the stage 1 can be suppressed. The workpiece 11 moved to the positioning position B by the negative pressure is not pulled back. Therefore, the position of the work 11 moved to the positioning position B does not change, and the work 11 can be positioned with high accuracy.
[0022]
Further, since the hole 5a having a large diameter is completely closed by the work 11 moved to the positioning position B, it does not function as escape of air sucked by the suction pump 10. On the other hand, since the hole 5b having a small diameter is not blocked by the work 11, it functions as a relief of the air sucked by the suction pump 10, but as described above, the total area of the holes 5a is larger than the total area of the holes 5b. Since the air that escapes through the hole 5b is reduced, the leakage of the vacuum on the stage 1 when the workpiece 11 is moved to the positioning position B is suppressed, and the air is placed at the positioning position B of the stage 1. The posture of the workpiece 1 placed thereon can be stabilized.
[0023]
As described above, in the pre-centering apparatus of this embodiment, the hole 5b is formed also at the placement position A where the work 11 is placed, and the work 11 placed at the placement position A is sucked and held by the stage 1. Thus, the posture of the workpiece 11 placed at the placement position A can be stabilized. As a result, it is possible to suppress the occurrence of trouble such as the workpiece 11 placed on the placement position A falling sideways, and the production efficiency can be improved. In addition, the opening 6 is provided in the positioning claw 2, and the negative pressure generated when the positioning claw 2 that has moved the workpiece 11 from the mounting position A to the positioning position B is returned to the original position is suppressed. The workpiece 11 moved to the positioning position B by the negative pressure is not pulled back, and the positioning accuracy of the workpiece 11 is not lowered.
[0024]
Further, in the automatic mounting machine to which the pre-centering device of the above embodiment is applied, the trouble occurrence frequency, which was about 2.5% in the past, can be improved to 0.05%, and the workpiece 1 is mounted on the substrate. The positional accuracy was also improved from ± 50 μm to ± 30 μm. However, as a result, the diameter of the hole 5a = 0.2 mm, the diameter of the hole 5b = 0.1 mm,
The suction amount of the suction pump 10 is ²⁰ l / min with respect to an area of 1 mm ² . The size of the workpiece 11 is 0.7 mm in length, 3.5 mm in width, and 0.5 mm in height.
[0025]
Next, another embodiment of the present invention will be described with reference to FIGS. In the pre-centering apparatus of this embodiment shown in FIG. 4, the diameter of the hole 5 formed in the stage 1 is made uniform, and the first suction that sucks the air above the stage 1 using the hole 5 formed in the positioning position B is used. The configuration differs from that of the above embodiment in that a pump 15 and a second suction pump 16 that sucks air above the stage 1 using the other holes 5 are provided.
[0026]
The pre-centering device of this embodiment stops the first suction pump 15 and operates only the second suction pump 16 when the workpiece 11 is placed at the placement position A of the stage 1 shown in FIG. Thus, the work 11 placed at the placement position A is sucked and held. Therefore, similarly to the above-described embodiment, the posture of the workpiece 11 placed at the placement position A can be stabilized, troubles such as the workpiece 11 falling sideways can be suppressed, and the production efficiency can be improved.
[0027]
When the workpiece 11 is moved from the placement position A to the positioning position B, the operation of the first suction pump 15 is started, and when the movement of the workpiece 11 to the positioning position B is completed, the second suction pump 16 is turned on. Stop. At this time, the first suction pump 15 is operating. As a result, when the positioning claw 2 that has moved the workpiece 11 to the positioning position B is returned to the original position, the negative pressure generated between the positioning claw 2 and the stage 1 is suppressed. The workpiece 11 moved to is not pulled back. Therefore, the position of the work 11 moved to the positioning position B does not change, and the work 11 can be positioned with high accuracy. Further, the hole 5 formed in a region other than the positioning position B does not function as a relief of the air that holds the work 11 by suction (the air sucked by the first suction pump 15). The posture of the moved work 11 can be stabilized.
[0028]
Thus, the pre-centering device of this embodiment also has the same effect as that of the above embodiment. In the above description, the two suction pumps of the first suction pump 15 and the second suction pump 16 are provided, but a piping system that performs suction using the hole 5 formed in the positioning position B; If a configuration for switching between a piping system for performing suction using holes 5 formed at other positions is provided, a single suction pump can be used.
[0029]
【The invention's effect】
As described above, according to the present invention, a hole is also formed at the placement position for placing the workpiece, and the workpiece placed on the stage is sucked and held, so that the workpiece is placed on the stage. The posture of the workpiece can always be stabilized, the frequency of troubles such as the workpiece falling sideways can be suppressed, and the production efficiency can be improved.
[0030]
In addition, since the diameters of the holes formed at the predetermined position of the stage and other positions are made different, it is possible to suppress the leakage of vacuum on the stage when the workpiece is moved to the predetermined position. The posture of the workpiece moved to the position can be stabilized.
[0031]
In addition , a first suction unit that performs suction using holes formed in predetermined positions and a second suction unit that performs suction using holes formed in other positions are provided. Even if the vacuum leak on the stage is suppressed, the posture of the workpiece can always be stabilized.
[0032]
Furthermore, since the opening functioning as the escape of the air sucked by the positioning claw is formed, the negative pressure generated when the positioning claw is retracted from the workpiece after the workpiece is moved to a predetermined position is suppressed, and the workpiece is The positioning accuracy can be improved.
[Brief description of the drawings]
FIG. 1 is a perspective view of a stage portion in a pre-centering apparatus according to an embodiment of the present invention.
FIG. 2 is a plan view of a stage portion in the pre-centering apparatus according to the embodiment of the present invention.
FIG. 3 is a diagram for explaining the operation of the pre-centering apparatus according to the embodiment of the present invention.
FIG. 4 is a perspective view of a stage portion in a pre-centering apparatus according to another embodiment of the present invention.
FIG. 5 is a plan view of a stage portion in a pre-centering apparatus according to another embodiment of the present invention.
FIG. 6 is a diagram for explaining the operation of the automatic mounting machine.
FIG. 7 is a perspective view of a stage portion in a conventional pre-centering apparatus.
FIG. 8 is a plan view of a stage portion in a conventional pre-centering apparatus.
[Explanation of symbols]
1-stage 2-positioning claw 5 (5a, 5b) -hole 6-opening 10-suction pump 11-work 15-first suction pump 16-second suction pump

Claims (2)

A stage on which an externally supplied workpiece is placed;
In a workpiece positioning device comprising a positioning claw for sliding the workpiece on the stage and moving it to a predetermined position,
In the stage, a large number of holes are formed in an area including a placement position where the workpiece is placed and the predetermined position.
In the area, the holes formed at the predetermined positions and the holes formed at other positions are different in diameter,
A work positioning apparatus comprising suction means for sucking and holding the work on the stage using the plurality of holes. The workpiece positioning device according to claim 1 , wherein an opening is formed in the positioning claw.

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