JPH03217029A - Position detecting apparatus - Google Patents

Abstract

PURPOSE:To obtain an apparatus which can detect the position of the tip of a tool simply with high accuracy by pushing and deforming a detecting part which is provided on a position detecting jig with the tip of the tool, photographing the detecting member, thereby obtaining the place where the detecting member is deformed, and detecting the coordinates of the tip of the tool. CONSTITUTION:A tool 11 is driven in the up and down directions. A table 8 which is driven in the horizontal direction is arranged so as to face the lower side of the tool 11. A detecting member 27 comprising a material which has high reflectivity and is readily subjected to plastic deformation is provided on the upper surface. A position detecting jig 24 having the member 27 is held on the table 8 so that the jig can be freely attached and removed. The detecting member 27 is pushed and deformed with the tip of the tool 11 by driving the tool 11 downward. An image photographing device 22 picks up the image of the detecting member 27 which is arranged on the table 8 and then pushed and deformed. An image processing device 23 processes the signal from the image photographing device and computes the coordinates of the part of the detecting member 27 deformed with the tool 11. For example, the tool 11 is a capillary 11 in a die bonder 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a position detection device suitable for detecting the position of a tool that handles extremely small parts.

(Prior art) For example, in a die bonder, 40
A very small light emitting diode chip of about 0 μm x 800 μm is sucked from a tray using a capillary as a tool and supplied to a bonding position. In that case, unless the tip position of the capillary is matched with the chip with high precision, the capillary may not attract the top surface of the chip but the side surface of the chip. Therefore, it is necessary to detect the positions of the chip and the capillary and position the capillary with respect to the chip with high precision.

To detect the position of the chip, light is applied to the chip housed in a tray on the chip stage, and an image of the tray is taken by an imaging device provided in the die bonder, thereby detecting the position of the chip.

On the other hand, since the capillary is provided with its tip facing the chip, the position of the tip cannot be detected by imaging it with the imaging device.

Therefore, conventionally, a mask plate b with a reference hole a formed therein is placed on the chip stage as shown in FIG. The tip of the capillary C was aligned with the reference hole a, thereby detecting the position of the capillary C.

However, if the position of the tip of the capillary C is detected in this way, the capillary C will be viewed diagonally from above using the microscope d, so the tip will be aligned with the reference hole a of the mask plate b with high precision. Sometimes things are difficult. Moreover, since the operator has to align the reference hole a and the tip of the capillary C with the naked eye, not only is the work efficiency poor, but the work time is also long.

(Problems to be Solved by the Invention) As described above, conventionally, the position of the tool tip was detected by observing it from diagonally above using a microscope, which caused problems in terms of accuracy and workability.

This invention was made based on the above circumstances, and its purpose is to provide a position detection device that can easily and highly accurately detect the position of the tip of a tool. .

[Structure of the Invention] (Means and Effects for Solving the Problems) In order to solve the above problems, the present invention provides a tool that is driven in the vertical direction;
This tool has a horizontally driven table disposed oppositely below it, and a detection member made of a material that has high reflectance and is easily plastically deformed by external force on its upper surface, and is detachably held on the table. Also, a position detection jig that presses and deforms the detection member at its tip by driving the tool downward, and an imaging device that is placed above the table and captures an image of the suppressed and deformed detection member. and an image processing device that processes signals from the imaging device to calculate coordinates of a portion of the detection member that has been deformed by the tool.

With this configuration, the coordinates of the deformed portion of the detection member correspond to the position of the tip of the tool, so the position can be detected quickly and accurately without relying on the naked eye of the operator.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. FIG. 2 shows a die bonder 1 used as a position detection device, and this die bonder 1 is equipped with a table device 2. As shown in FIG. This table device 2 has an X drive body 4 driven in the X direction by an X drive motor 3 and a Y drive body 6 driven in the Y direction by a Y drive motor 5. A table 8 is provided, the lower surface of which is supported horizontally by supports 7 at its four corners.

A groove 9 is formed in the upper surface of the table 8, into which a tray (not shown) containing a large number of light emitting diode chips or the like in rows and columns can be removably positioned.

Above the table device 2 is a cavity 11 for vacuum suctioning the chips housed in the tray as a tool.
is located. This cavity 11 is detachably held by a suction mechanism 14 provided at the tip of a Z drive body 13 driven in the Z direction (vertical direction) by two drive motors 2 and connected to a vacuum source (not shown). A slider 5 is fixed to the rear end of the Z drive body 13, and the slider 15 is provided on a mounting body 16 so as to be slidable in two directions. The two drive motors 2 are held on the mounting body 16 by a bracket 17, and the connection member 18 is driven in the vertical direction by the rotation of the rotation shaft of the Z drive motor 2. The slider 5 is connected to this connecting member 18, so that the two drive bodies 13 are driven in the vertical direction.

The mounting body 16 is slidably held by an upper guide body 19 in the form of a horizontally installed strip, and the mounting body 16 is driven in the horizontal direction by a driving means 21.

A TV camera 22 as an imaging device is disposed above the table 8, and the TV camera 22 takes an image of the tray positioned in the groove 9 of the table 8. The TV camera 22 has an image processing device 2
3 is connected, and this image processing device 23 allows the above-mentioned TV
The image signal from the camera 22 is processed. That is, when a tray containing a chip is placed in the groove 9 and the TV camera 22 images the tray, since the reflectance of light differs between the chip and other parts, the image signal is transmitted to the image processing device. 23, the X of each chip accommodated in the tray is determined by the difference in brightness.
It is now possible to detect the coordinates of the direction and the Y direction.

When detecting the coordinates of the tip of the capillary 11 held by the suction mechanism 14, a position detection jig 24 is attached to the groove 9 of the table 8. As shown in FIG. 1, this position detection jig 4 has a rectangular plate shape approximately the same size as the above-mentioned tray, and a through hole 25 penetrating in the thickness direction is formed in a part thereof. This through hole 25 is covered with a detection member 27 attached to the upper surface of the position detection jig 24 with cellophane tape 26 or the like. The detection member 27 is made of a material such as aluminum foil, which has a high light reflectance and is easily plastically deformed by external force.

The above X drive motor 3, Y drive motor 5, Z drive motor 1
2. The driving means of the mounting body 16 and the image processing device 23 are connected to a control device 28, which controls each motor 3.
, 5, and 12 are driven and controlled based on coordinate signals detected by the image processing device 23.

Next, a procedure for detecting the position of the tip of the capillary 11 will be explained. First, the position detection jig 24 is attached to the groove 9 of the table 8, and the table 8 is driven as shown in FIG. 3(a).
The capillary 11 is positioned above the location of the detection member 27 of the position detection jig 24, as shown in FIG. At this time, the X direction and Y direction of the tip of the cavity 11
The coordinates of each direction are stored in the control device 28 as zero.

Next, the cavity 11 is lowered as shown in FIG. 3(b), and the detection member 27 is pressed with its tip. Then, since the detection member 27 is pressed and deformed by the capillary 11, a concave portion is formed at that location, which is plastically deformed and protrudes into the through hole 25 of the position detection jig 24, as shown in FIG. 3(C). A dent 27a will be formed.

Once the dent 27a is formed on the detection member 27 in this way, the table 8 is driven so that the dent 27a is located below the TV camera 22 as shown in FIG.
The detection member 27 is imaged by the V camera 22, and the image signal is processed by the image processing device 23. When the TV camera 22 takes an image of the detection member 27 on which the dents 27a are formed, the light from the TV camera 22 that illuminates the detection member 27 is reflected upward at the dents 27a, and the light from the TV camera 22 that illuminates the detection member 27 is reflected upward from the dents 27a on the detection member 279 other than the dents 27a. Because of the diffused reflection in the area, there is a difference in brightness between the location of the dent 27a and other locations on the detection member 27, which allows the image processing device 23 to identify the dent 27a. Further, the amount of movement of the table 8 at this time is stored in the control device 28.

Therefore, the image processing device 23 allows the dents 2 to be
Since the coordinates of point 7a can be determined, if the coordinate values are corrected based on the amount of movement of the table 8 up to that point stored in the control device 28, the dent 27 can be found on the detection member 27.
The coordinates of the tip of the capillary 11 forming the shape a can be determined.

Once the coordinates of the tip of the capillary 11 have been detected in this way, a tray is attached to the groove of the table 8 in place of the position detection jig, and the coordinates of the chip are detected. By driving the table 8 according to the coordinates of the capillary 11 and aligning the tip of the capillary 11 with the chip, the tip of the capillary 11 can reliably adsorb the upper surface of the chip housed in the tray.

1 0 Also, in this embodiment, the capillary 11 of the die bonder 1
In order to detect the position of the tip of the capillary 11, it is possible to detect the position of the tip of the capillary 11 using the table device 2, the TV camera 22, the image processing device 23, etc., which are naturally necessary devices for the die bonder 1. Therefore, the position of the tip of the capillary 11 can be detected without using any special equipment for position detection.

In the above embodiment, aluminum foil was used as the detection member provided in the position detection jig, but it may be made of other materials. Any material that is easily deformable may be used. Further, the means for attaching the detection member to the position detection jig is not limited to cellophane tape, and may be other means.
The point is that it only needs to be fixed to the position detection jig.

Furthermore, although the above embodiment is applied to a die bonder, it can also be applied to other devices.In short, parts arranged in a state where the coordinates can be detected are moved by a tool such as a capillary to the 11 upper part. Any device can be applied as long as it holds the object and transports and positions it at an appropriate location.

[Effects of the Invention] As described above, according to the present invention, the detection member provided in the position detection jig is pressed and deformed by the tip of the tool,
By taking an image of the detection member, the coordinates of the location where the detection member has been deformed by the tool are determined, thereby detecting the coordinates of the tip of the tool. Therefore, since the position of the tip of the tool can be detected by imaging the detection member from directly above, it is possible to detect the tip more accurately than in the past, which required detection from diagonally above using a microscope. Moreover, it has the advantage that the detection work can be performed quickly without requiring any skill.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a position detection jig showing an embodiment of the present invention, FIG. 2 is a perspective view of the schematic configuration of a die bonder, and FIGS. 3(a) to (c) are views of the position detection jig. FIG. 4 is an explanatory diagram showing the steps of making a mark on a detection member and detecting its coordinates. FIG. 4 is an explanatory diagram showing a conventional position detecting means. 8...Table, 11...Tool (capillary), 2
2... Imaging device, 23... Image processing device, 24...
- Position detection jig, 27... detection member.

Claims (1)

[Claims] A tool that is driven in the vertical direction, a table that is driven in the horizontal direction that is disposed opposite to the tool below, and a detection member that is made of a material that has high reflectance and is easily plastically deformed by external force is provided on the top surface. a position detection jig that is detachably held on the table and that presses and deforms the detection member at its tip by driving the tool downward; A position detection device comprising: an imaging device that images a sensing member; and an image processing device that processes signals from the imaging device to calculate coordinates of a portion of the sensing member that has been deformed by the tool. Device.