JP2814726B2 - Electronic component mounting apparatus and electronic component mounting method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an electronic component mounting apparatus and an electronic component mounting method for precisely performing θ correction of a chip adsorbed on a nozzle of a transfer head and mounting the chip on a substrate. Things.

(Prior Art) FIG. 4 shows a conventional electronic component mounting apparatus, in which 101 is a rotary head, and 102 is a rotary head 10.
A transfer head vertically mounted on 1, a nozzle 103 for sucking the chip P, and a nozzle 104 for correcting a positional shift of the chip P in the θ direction (a rotation direction about the axis of the nozzle 103).
A motor for rotating 103 in the θ direction, a belt 105, and an XY direction moving device 106 on which a substrate 107 is disposed.

In this apparatus, when the rotary head 101 performs index rotation, the nozzle P sucks and takes up the chip P in the chip supply unit (not shown) and transfers the chip P to the substrate 107. Between the chip supply unit and the XY direction moving device 106, an observation device (not shown) for observing the displacement of the chip P sucked by the nozzle 103 in the XYθ direction is provided.
Based on the observation results, the displacement in the XY direction is corrected by driving the XY direction moving device 106 to move the substrate 107 by the same amount in the same direction.
The correction is performed by driving the nozzle 104 to rotate the nozzle 103.

(Problems to be Solved by the Invention) By the way, there is a limit to the minimum rotation angle of the motor 104. Therefore, in order to perform a minute θ correction, the pulley ratio of the pulley on which the belt 105 is tuned must be increased. Thus, the rotation speed of the motor 104 must be sufficiently reduced. However, when the pulley ratio is increased in this manner, the rotation speed of the nozzle 103 is reduced and the mounting efficiency is reduced accordingly, and the belt 105 is easily stretched and the mounting accuracy is easily lowered, and further, the capacity of the motor 104 is increased. Therefore, there is a problem in that the device becomes large and heavy. Such a problem similarly occurs when the rotation of the motor 104 is transmitted to the nozzle 103 by another reduction means such as a gear instead of a belt or a pulley. Such a problem is not limited to a rotary head type electronic component mounting device equipped with a large number of transfer heads, but an electronic component of a type in which the transfer head is moved in the XY direction to transfer and mount the chip in the chip supply unit to the substrate. This also occurs in the case of a mounting device.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an electronic component mounting apparatus and an electronic component mounting method provided with means capable of performing θ correction of a chip sucked to a nozzle with high speed and high accuracy.

(Means for Solving the Problems) For this purpose, the present invention provides a chip supply unit, a substrate positioning device, and a chip of the chip supply unit sucked by a nozzle and transferred to a substrate positioned by the positioning device. A transfer head, an observation device for detecting a displacement of a chip adsorbed on the nozzle, and a nozzle rotating means for rotating the nozzle to perform coarse correction in the θ direction of the chip adsorbed on the nozzle. In the electronic component mounting apparatus, the positioning unit is provided with a portion on which the substrate is disposed so as to be freely rotatable about a rotation axis, and the disposition portion is horizontally rotated to correct the positional deviation of the chip in the θ direction. A drive device is provided.

The present invention also provides a process in which the transfer head sucks and picks up a chip in a chip supply unit to a nozzle, a step in which the picked up chip is observed by an observation device to detect a chip displacement, and Means for roughly correcting the displacement of the chip in the θ direction by rotating the means, and driving the driving unit to horizontally rotate the arrangement portion of the substrate provided on the positioning device about the rotation axis. An electronic component mounting method characterized by including a step of finely correcting a positional shift in a direction and a step of mounting a chip on which a positional shift has been corrected on a substrate.

(Operation) According to the above configuration, the chip is mounted on the substrate after the chip is precisely θ-corrected by driving the driving device to horizontally rotate the arrangement portion.

Embodiment Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 2 is a perspective view of a main part of the rotary head type electronic component mounting apparatus, wherein 1 is a rotary head, and a number of transfer heads 2 are suspended along the circumferential direction. Reference numeral 3 denotes a chip supply unit comprising a tray provided below the rotary head 1, and reference numeral 4 denotes an XY direction moving device as a device for positioning the substrate 5. A tape feeder or a tube feeder is often used as a chip supply unit.

The chip P adsorbed by the transfer head 2 is observed from below between the chip supply unit 3 and the XY direction moving device 4,
An observation device 7 including a camera 6 for detecting a positional shift in the XYθ direction is provided. The rotary head 1 rotates in the index direction in the horizontal direction N 1, and accordingly, the transfer head 2 sucks and picks up the chip P of the chip supply unit 3 and transfers it to the substrate 5. Reference numeral 8 denotes a conveyor for carrying the substrate 5 into and out of the XY-direction moving device 4.

FIG. 1 shows the transfer head 2 and the XY direction moving device 4 in detail. The transfer head 2 includes a main body case 11, a nozzle 12 protruding from a lower portion of the main body case 11, and a pulse motor 13 as a nozzle rotating means for rotating the nozzle 12 in the θ direction. The chip P sucked by the nozzle 12 is a QFP having leads 14 protruding in four directions. Since QFP has a large number of leads 14 and a small pitch, extremely high mounting accuracy is required. Of course, not only QFP, but also SOPs having two-way leads, resistor chips, capacitor chips, and the like can be mounted.

Reference numeral 16 denotes an arrangement portion of the substrate 5 provided on the XY direction moving device 4, and clamp members 17a and 17b for clamping and positioning the substrate 5 from both sides are provided on both sides thereof. In addition, the corner is moved by the rotating shaft 18 in the XY direction
It is mounted on the top so that it can rotate horizontally.

Reference numeral 20 denotes a driving device for horizontally rotating the disposing portion 16 (see also FIG. 3), reference numeral 21 denotes a motor, reference numeral 22 denotes a feed screw, and reference numeral 23 denotes a nut. A roller 24 is provided on the nut 23, and the nut 24 is engaged with an engaging element 25 protruding from the XY direction moving device 4. Therefore, when the motor 21 is driven, the nut
23 reciprocates along the feed screw 22, and the disposition portion 16
Rotate horizontally around. The present apparatus has the above configuration, and the operation will be described next.

With the rotation of the index of the rotary head 1,
The chip P of the chip supply unit 3 is sucked by the lower end of the nozzle 12 and transferred toward the substrate 5 positioned by the XY direction moving device 4. On the way, the observation device 7 detects a positional shift in the XYθ direction of the chip P sucked by the nozzle 12.

The displacement in the XY direction is corrected by driving the XY direction moving device 4 to move the substrate 5 in the XY direction. The displacement in the θ direction is corrected by driving the motor 13 and the motor 21. That is, when the motor 13 is driven, the nozzle 12 rotates in the θ direction. However, since the minimum rotation angle of the motor 13 is limited as described above,
Due to the rotation of 12, it is difficult to correct the positional deviation in the θ direction with high speed and high accuracy. Therefore, a coarse correction (for example, a correction of 5 ° or more) is performed by the motor 13 and a fine correction (for example, a correction of 5 ° or less) is performed by horizontally rotating the arrangement unit 16 by the other motor 21.

As described above, if only the rough correction is performed by the θ correction motor 13 mounted on the transfer head 2, the motor 13
No large deceleration is required, and the nozzle 12 can be rotated at a high speed even with a small capacity motor 13. In addition, since the fine correction is performed by driving the motor 21 of the driving device 20 to horizontally rotate the disposition unit 16, the θ correction of the chip P can be performed accurately at high speed and mounted on the substrate 5. . It should be noted that the displacement in the XY direction newly generated in association with the θ correction can be easily corrected by driving the XY direction moving device 4 in the same direction.

By the way, in order to accurately perform the θ correction, it is necessary to assemble the rotating shaft 18 of the disposing portion 16 so as to coincide with the coordinate origin of the substrate 5. However, the rotation axis 18 does not always coincide with the coordinate origin of the substrate 5 due to an assembly error. Therefore, the actual rotation center is obtained as follows.

In FIG. 3, 5a is a jig for the substrate, O (xO, yO) is an origin arbitrarily provided on the jig 5a, and X1 and Y1 are formed on the same X-axis and Y-axis as the origin O. Mark.

First, the origin O is observed with a camera (not shown). Next, the jig 5a is moved in the X direction, and the mark X1 is observed. At this time, if the mark X1 is shifted from the center of the field of view of the camera, this is stored as a movement error of the XY direction movement device 4,
This error will be corrected later.

Next, the motor 21 is driven to slightly rotate the jig 5a, and the turning points X1a and X1b are observed by the camera. Then turn point X1
Find the perpendicular bisector Nx of a and X1b.

Perform the same operation for the mark Y1 as
A vertical bisector Ny of Y1a and Y1b is obtained.

The intersection O '(xO', yO ') of the perpendicular bisector Nx, Ny is the actual center of rotation. When the coordinates of the rotation center O 'are known in this way, the distance L to the axis of the feed screw 22 is determined from this.

When the distance L is obtained in this manner, the feed amount of the nut 23 required to rotate the substrate 5 by an arbitrary angle can be calculated, and precise θ correction can be performed. If the true rotation center O 'is obtained as described above, the substrate 5
Can also be calculated by horizontally rotating the XY direction, and this error can be corrected by moving the XY direction moving device 4.

Although the above embodiment has been described taking the rotary head type electronic component mounting apparatus as an example, the present invention is directed to another type of electronic component mounting apparatus in which a chip is transferred and mounted on a substrate while moving the transfer head in the XY direction. Also applicable to

(Effects of the Invention) As described above, according to the present invention, it is possible to precisely correct the displacement in the θ direction of the chip sucked by the nozzle of the transfer head and mount the chip on the substrate.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 1 is a perspective view of a transfer head and an XY direction moving device, FIG. 2 is a perspective view of a rotary head type electronic component mounting device, and FIG. FIG. 4 is a plan view of the installation portion, and FIG. 4 is a perspective view of the conventional device. 2 Transfer head 3 Chip supply unit 4 Positioning device 5 Substrate 7 Observation device 11 Nozzle 16 Arrangement unit 20 Drive unit

Claims (2)

(57) [Claims] 1. A chip supply unit, a substrate positioning device,
A transfer head for sucking the chips of the chip supply unit to the nozzle and transferring the chips to the substrate positioned by the positioning device, an observation device for detecting a displacement of the chip sucked by the nozzle, and rotating the nozzle. In the electronic component mounting apparatus having nozzle rotating means for performing rough correction in the θ direction of the chip adsorbed by the nozzle, the positioning unit is provided so that the substrate mounting portion can be horizontally rotated about the rotation axis. An electronic component mounting apparatus, further comprising: a driving device for horizontally rotating the disposing portion to correct the displacement of the chip in the θ direction. A step of picking up a chip in a chip supply section by a nozzle by a transfer head; and a step of observing the picked-up chip by an observation device to detect a displacement of the chip; Rotating the chip by means to roughly correct the chip position shift in the θ direction;
A step of finely correcting the position shift of the chip in the θ direction by driving the driving device to horizontally rotate the rotation of the arrangement portion of the substrate provided on the positioning device, and the chip having the position shift corrected. Mounting an electronic component on a substrate.