JP2929800B2 - Stop position determination method for electronic component suction nozzle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of determining a stop position of an electronic component suction nozzle, and more particularly, to irradiating a nozzle of a multi-nozzle transfer head to detect the presence of an electronic component pickup error. The present invention relates to a means for correctly stopping the slit light in the optical path.

[0002]

2. Description of the Related Art A rotary head type chip mounting apparatus known as a chip mounting apparatus for automatically mounting electronic components (hereinafter, referred to as chips) on a substrate at a high speed uses an index rotation of a plurality of transfer heads provided on the rotary head. While the parts feeder is reciprocating in the horizontal direction, the chip of the parts feeder stopped at the pickup position is picked up by the transfer head, and the chip is mounted on the substrate positioned on the XY table. .

The rotary head type chip mounting apparatus has an advantage that a chip can be mounted on a substrate at a high speed, but has a disadvantage that the mounting speed is high, so that a chip pick-up mistake by a transfer head is apt to occur frequently. This pick-up mistake includes no chip (when the chip could not be picked up), chip standing (when the chip was picked up in a standing position), and erroneous pickup (when a chip of a different type was picked up). As means for detecting such a pickup error, means utilizing slit light as described below is known.

FIG. 1 is a perspective view of a chip mounting device equipped with a pickup error detecting device. Reference numeral 1 denotes a rotary head provided with a plurality of multi-nozzle transfer heads 2. The transfer head 2 is provided with a plurality of nozzles 3 for sucking the chips P.

In FIG. 2, M is a motor for rotating the transfer head 2 to select a nozzle and correct a rotation angle, and 12 is a computer for controlling the motor M. 13 is a pulley on the motor M side, 14 is the transfer head 2
The pulley 15 on the side is a timing belt adjusted to both pulleys 13 and 14. When the motor M is driven by a command from the computer 12, the timing belt 15 rotates and the transfer head 2 rotates about its axis O, and selects the optimal nozzle 3 for the chip P to be picked up.

In FIG. 1, reference numeral 4 denotes a chip supply unit,
The rotary head 1 is disposed below the peripheral portion.
A parts feeder 5 is mounted on the base 6 of the chip supply unit 4 so as to be movable in the X direction. Reference numeral 7 denotes an XY table on which the substrate S is placed, which is disposed below the rotary head 1 on the side opposite to the chip supply unit 4.

In FIG. 1 and FIG. 2, reference numeral 8 denotes a laser device provided in the middle of the moving path of the transfer head 1, which comprises a light emitting portion 9 of a laser slit light 11 and a light receiving portion 10; Longitudinal laser slit light 11 is emitted from 9 to the light receiving unit 10.

The present apparatus has the above-described configuration, and the operation will be described next. Prior to mounting the chip, the height of the lower end of each nozzle 3 is determined in advance as follows.
That is, first, as shown in FIG.
Is driven, the transfer head 2 is rotated by the index, and the transfer head 2 is moved between the light emitting unit 9 and the light receiving unit 10.
Next, at this position, the height of the lower end of the nozzle 3 projecting from the transfer head 2 (hereinafter, referred to as the nozzle height) is detected as follows. In FIG. 3, of the slit light 11 emitted from the light emitting unit 9, the portion irradiated to the nozzle 3 is blocked by the nozzle 3 and does not enter the light receiving unit 10, and the output of the light receiving unit 10 decreases accordingly. From that
Based on the output value, the nozzle height H from the reference level L
Is required. By repeating the above operation, the nozzle heights of all the nozzles 3 of all the transfer heads 2 are obtained,
Register in the computer 12.

After the nozzle heights of all the nozzles 3 have been determined as described above, the chip P is mounted. When mounting the chip P, the motor M is driven to rotate the transfer head 2, the nozzle 3 optimal for the chip P to be picked up is selected, and then the transfer head 2 is mounted on the chip supply unit 4. The chip P of the parts feeder 5 is picked up by the nozzle 3 by moving up and down.

Next, the transfer head 2 is rotated by an index by driving the rotary head 1, and the transfer head 2 is stopped between the light emitting unit 9 and the light receiving unit 10. Here, as shown in FIG. 4, the nozzle 3 and the chip P are irradiated with the slit light 11 from the light emitting unit 9 and the output of the light receiving unit 10 is obtained by the same method as in the case of the measurement of the nozzle height H described above. The height h (hereinafter, referred to as a chip height) of the lower surface of the sucked chip P is measured. Next, the thickness d of the chip P is obtained from the difference between the nozzle height H and the chip height h, and the measured thickness d is compared with the thickness of the chip P registered in the computer 12 in advance, so that no chip exists. It is determined whether there is a pickup error such as a chip standing or an erroneous pickup.

If there is no pick-up error, the rotary head 1 is driven to move the transfer head 2 on which the chip P is sucked onto the XY table 7, where the chip P is moved up and down. It is mounted on the substrate S.
If a pickup error is detected, the chip P
Mounting on the substrate S is stopped, and the chip P is abandoned at an appropriate place.

[0012]

However, when this pick-up error is detected, the slit light emitted from the light-emitting section 9 as shown by the chain line in FIG. 5 due to a mechanical error such as an assembly error of the nozzle 3, for example. In some cases, the stop position of the nozzle 3 is shifted from the optical path of the nozzle 11. When the nozzle 3 is shifted in this way, the nozzle 3 or the chip P does not block the slit light 11, and the nozzle 3 is moved by the method shown in FIGS. The height and the chip height cannot be detected.
However, in the conventional means, no countermeasure has been taken in such a case, and therefore, there has been a problem that it is easy to erroneously determine the presence or absence of a pick-up error of the chip P.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method capable of correctly stopping a nozzle in an optical path of slit light in order to detect a pickup error.

[0014]

According to the present invention, a transfer head is positioned between a light-emitting portion and a light-receiving portion, and a motor is driven to rotate the transfer head so that the nozzle of the transfer head emits light. The slit light emitted from the unit to the light receiving unit is traversed, and the position where the nozzle blocks the slit light is detected from the output of the light receiving unit at that time.

[0015]

In the above construction, the transfer head is positioned between the light emitting section and the light receiving section by driving the rotary head.
By driving the motor and rotating the transfer head,
The nozzle is made to cross the slit light, and the position where the nozzle blocks the slit light is detected from the output of the light receiving unit at that time.

In this way, if the positions where the nozzles completely block the slit light are determined in advance for all the nozzles, when the chips are transferred and mounted on the substrate by the nozzles, the stop positions of the nozzles are determined. After correction, the nozzle can be correctly stopped at the position where the optical path of the slit light is blocked, so that the presence or absence of chip pickup error can be reliably detected.

[0017]

Next, an embodiment of the present invention will be described with reference to the drawings. The configuration of the apparatus used in this embodiment is the same as the conventional apparatus shown in FIGS.

In this means, in order to reliably detect the presence or absence of a chip pick-up error,
Determine the stop position of the nozzle. That is, the rotary head 1 is driven to rotate the transfer head 2 by the index, and the nozzle 3 protruding from the transfer head 2 is stopped at the position a (see FIG. 2) between the light emitting unit 9 and the light receiving unit 10. . It is unknown whether the nozzle 3 has stopped correctly on the optical path of the slit light 11 due to a rotation stop position error due to the driving of the motor M, an assembly molding error, and the like.

Then, the motor M is driven to rotate the nozzle 3 around the position a by an arbitrary angle θ (for example, about 5 °) in the direction of the arrow N, and the output voltage of the light receiving unit 10 at that time is changed. Seek change. Positions b and c shown by broken lines in the figure
Is the maximum rotation position of the nozzle 3.

FIG. 6 shows the light receiving section 1 when the above operation is performed.
FIG. 7 is a change diagram of the output voltage V at 0, and the angle Δ
At the position a 'displaced by θ, the output voltage V becomes the minimum value Vmin. Therefore, if the rotation angle of the transfer head 2 driven by the motor M is corrected by Δθ, the nozzle 3
1, the slit light 11 is completely shielded, and the slit light 11 is completely blocked, and by the method described with reference to FIGS.
The nozzle height H and the tip height h can be accurately measured. It should be noted that when the position a 'is determined by rotating the nozzle 3 by the angle θ as described above, it is desirable that the nozzle height H is also determined at the same time by the method shown in FIG.

The nozzle height H and the correction angle Δθ are obtained for all the nozzles 3 of all the transfer heads 2 by the same method as described above, and the results are stored in the computer 12.
Register with. Then, while sequentially rotating each transfer head 2 by index rotation, the chip P of the parts feeder 5 is sucked and picked up by any one of the nozzles 3, and during the transfer and mounting on the substrate S, the nozzles 3 receive light from the light emitting unit 9. By stopping between the sections 10 and driving the motor M to correct the angle Δθ, the nozzle 3 and the chip P are correctly positioned in the optical path of the slit light 11 as shown in FIG. Can be detected.

The present invention is not limited to the above embodiment. For example, in FIG.
Is temporarily stopped at a position b before the light path is predicted to be present, and the nozzle 3 is rotated from the position b to a position c predicted to pass through the light path, so that the output voltage V
May be determined by detecting the position a 'at which the minimum value Vmin is obtained, and the rotation angle δ at that time (see FIG. 6). Alternatively, the laser device 8 is rotated around the nozzle 3 while the nozzle 3 is stopped. Thus, the rotation angle at which the minimum value Vmin appears may be obtained.

[0023]

As described above, according to the present invention, the transfer head is positioned between the light-emitting portion and the light-receiving portion, and the motor is driven to rotate the transfer head. , And by detecting the position where the nozzle blocks the slit light from the output of the light receiving unit at that time, the nozzle stop position is determined.
By properly stopping the nozzle in the optical path of the slit light, it is possible to reliably detect the presence or absence of a chip pickup error.

[Brief description of the drawings]

FIG. 1 is a perspective view of a chip mounting apparatus according to the present invention.

FIG. 2 is a plan view of the main part.

FIG. 3 is a front view of a main part during the nozzle height detection.

FIG. 4 is a front view of a main part during the pickup error detection.

FIG. 5 is a plan view of the main part.

FIG. 6 is a characteristic diagram of an output voltage of the light receiving unit.

[Explanation of symbols]

 2 Multi-nozzle transfer head 3 Nozzle 5 Parts feeder 7 XY table 9 Light emitting unit 10 Light receiving unit 11 Slit light M Motor P Electronic component S Substrate

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H05K 13/04 H05K 13/08 G06T 7/00

Claims (1)

(57) [Claims] 1. A multi-nozzle transfer head having a plurality of nozzles is rotated by driving a motor to select a nozzle most suitable for an electronic component to be picked up, and then the transfer head is rotated by an index. While picking up, the electronic parts of the parts feeder are sucked and picked up by the above-mentioned nozzle, and then the nozzle is stopped in the middle of the moving path of the transfer head, so that the slit light emitted from the light emitting section is emitted to this nozzle and the electronic parts. Irradiating, and determining whether there is a pick-up error from the output of the light receiving unit, and then mounting the electronic component on a substrate positioned on an XY table. The nozzle is positioned between the light receiving sections, and the motor is driven to rotate the transfer head. Cross were, the electronic component on stopping position determination suction nozzle, characterized in that the nozzles from the output of the light receiving unit at that time was to detect the position for blocking the slit light.