JPS63300600A - Method and apparatus for mounting electronic component - Google Patents

Abstract

PURPOSE:To avoid the decrease in an electronic component mounting efficiency and to eliminate a damage by substantially maintaining the falling distance of a suction nozzle constant irrespective of the height change of the component. CONSTITUTION:Compression coil springs 140, pistons 146, air chambers 158 and air supply units form height regulators 128. As a lower frame 84 moves up or down, an upper frame 82 placed thereon moves up or down to adjust elevational position with respect to a Y-axis slide 92 of a table 80, thereby altering the elevational position of a printed substrate 4 supported by the frame 82. The height of the table 80 is adjusted in advance in coincidence with the height of an electronic component 44. When an electronic component having a low height is mounted on the printed substrate 4, the table 80 is positioned at its raised position, while when an electronic component having a high height is mounted on the substrate 4, it is positioned at its lowered position. According ly, a spring 46 is compressed to apply a pressing force to the component 44, but not excessively compressed to prevent the component 44 from damaging or displacing.

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD The present invention relates to a method for mounting electronic components onto a printed circuit board and an apparatus used to carry out the method.

Conventional technology A device for mounting electronic components on a printed circuit board includes an electronic component holding device and a printed circuit board supporting device, as described in the specification of Japanese Patent Application No. 60-281596 filed by the applicant of the present invention. There are some things that are configured to include. In this application, an electronic component holding device is equipped with a suction nozzle that suctions electronic components by vacuum, and the suction nozzle is positioned directly above the electronic component mounting location on a printed circuit board and is lowered to print the electronic component. The board support device supports the printed circuit board with a table moved by a moving device, and moves the table to position the printed circuit board at a predetermined position, that is, the location where electronic components are mounted. The suction nozzle is positioned directly below the suction nozzle.

In addition, the printed circuit board supporting device supports the printed circuit board at a predetermined position using a table, and the electronic component holding device supports the printed circuit board by moving the suction nozzle in a direction parallel to the board surface of the printed circuit board. An electronic component mounting device configured to be positioned directly above the component mounting location,
An electronic component mounting device in which the electronic component holding device is moved toward and lowered toward the electronic component mounting location on the printed circuit board with the suction nozzle suctioning the electronic component, and the electronic component is mounted on the printed circuit board. There is also.

Conventionally, in this type of electronic component mounting device, the distance in the vertical direction between the starting position of the suction nozzle and the printed circuit board is constant, and the downward stroke of the suction nozzle is constant, and these are not adjusted. It wasn't.

The problem that the invention aims to solve As a result, various problems have arisen as described below.

For example, if the electronic component is tall and the distance between the suction nozzle and the printed circuit board is small, a problem arises in that the tall electronic component cannot be mounted. In this case, it is possible to mount expensive electronic components by increasing the distance between the suction nozzle and the printed circuit board.
If this is done, the suction nozzle must be lowered with a large stroke even when mounting a low-height electronic component, which deteriorates the mounting efficiency.

In addition, in the electronic component holding device, in order to securely mount the electronic component on the printed circuit board, the downward stroke of the suction nozzle is set to be wider than the distance between the electronic component and the printed circuit board that are attracted by the suction nozzle (and the suction nozzle An elastic member is often provided between the suction nozzle and the member that holds it, or between the tip of the suction nozzle and the main body, and the excess downward stroke is absorbed by the flexure of the elastic member.

In that case, when mounting multiple types of electronic components with different heights on a printed circuit board, the downward stroke of the suction nozzle must be set to match the electronic components with small heights. If the height is high, the stroke absorbed by the elastic member will be large. The descending distance of the suction nozzle is smaller than the descending distance when the electronic component is short, and the amount of deflection of the elastic member increases to absorb this difference, which increases the pressing force applied to the electronic component. This may cause damage to the electronic components, and when the electronic components are temporarily mounted on the printed circuit board, the printed circuit board may flex (or vibrate), causing the electronic components to be misaligned after mounting. Sometimes I put it away.

Furthermore, if the suction nozzle is moved up and down by a push-down device equipped with a cam, and the descending speed is fast at the beginning of the descent, but the descending speed is slow when the electronic component comes into contact with the printed circuit board, If the component is tall, the electronic component will collide with the printed circuit board at high speed, and the impact generated upon contact will be large, increasing the risk of damage to the electronic component, printed circuit board, etc.

Means for Solving the Problems In order to solve the various problems mentioned above, a method according to the present invention is a method of lowering a suction nozzle that has suctioned an electronic component, and mounting the electronic component at an electronic component mounting location on a printed circuit board. If the height of the electronic component is high, the distance from the printed circuit board to the starting position of the suction nozzle should be increased in step 1, and if the height of the electronic component is low, the distance should be decreased to remove the electronic component. The descending distance of the suction nozzle for mounting on the printed circuit board is kept almost constant regardless of changes in the height of the electronic component. In order to change the distance between the descending start position and the printed circuit board, the height of the printed circuit board may be changed or the height of the suction nozzle before descending may be changed.

Furthermore, the apparatus according to the present invention includes an electronic component holding device including a suction nozzle that is lowered while sucking the electronic component (Al) by vacuum, and attaches the electronic component to the electronic component attachment location of the printed circuit board; b) An electronic component mounting device equipped with a printed circuit board support device that supports a printed circuit board with a table, in which the table is provided to be movable in the vertical direction and a height adjustment device is provided to adjust the height of the table. It is.

Effects and Effects As in the method according to the present invention, if the descending distance of the suction nozzle is kept almost constant regardless of changes in the height of the electronic component, the height can be increased while avoiding a decrease in the mounting efficiency of electronic components with a low height. This makes it possible to mount electronic components with a high level of performance.

In addition, if the extra downward stroke of the suction nozzle is absorbed by the elastic member, the downward stroke of the suction nozzle is kept almost constant, so the amount of deflection of the elastic member becomes almost constant, and the electronic parts are printed. The printed circuit board is not pressed with an excessive pressing force, so there is no risk of damage, and the printed circuit board is less deflected, resulting in less vibration, eliminating the risk of misalignment of electronic components. By reducing the deflection of the printed circuit board, it is possible to obtain the effect that the supporting device for the printed circuit board can be simple.

Further, when the suction nozzle is moved up and down by a push-down device equipped with a cam, the impact when a tall electronic component comes into contact with a printed circuit board is small, and there is no risk of damage to the electronic component.

According to the apparatus according to the present invention, in addition to being able to carry out the method of the present invention, the distance between the printed circuit board and the suction nozzle can be easily changed compared to the case where the height of the suction nozzle is adjusted. can get. Since the electronic component holding device including the suction nozzle usually has many moving parts, it is difficult to adjust the height of the suction nozzle in a manner that does not interfere with the operation of these moving parts. However, when adjusting the height of the table that supports the printed circuit board, there are fewer such problems.

Embodiments Hereinafter, embodiments of the method and apparatus according to the present invention will be described in detail with reference to the drawings.

1 and 2 show a printed circuit board support device 2 constituting an electronic component mounting device which is an embodiment of the device according to the present invention. This support device 2 supports the printed circuit board 4 and positions it at a predetermined position.Although not shown, a printed circuit board loading device and a printed circuit board unloading device are provided on both left and right sides in the figure. These carry-in devices and *out device are the carry-in devices described in Japanese Unexamined Patent Application Publication No. 168299/1989 filed by the present applicant.

It has the same configuration as the unloading device, and its width (dimension in the direction perpendicular to the printed circuit board feeding direction) is adjustable, so that it can transport multiple types of printed circuit boards of different sizes.

Electronic components are mounted on the printed circuit board 4 by an electronic component holding device 8 shown in FIG. This holding device 8 is
The structure is almost the same as that of the holding device according to Utility Model Application No. 62-51512 filed by the present applicant, and will be briefly explained based on the drawings.

In the figure, 10 is a rotating body, and this rotating body 10 is attached to a frame (not shown) so as to be rotatable around a vertical axis.The rotation of the rotating body moves a suction nozzle, which will be described later, to an electronic component suction position, an electronic component mounting position, etc. It is now possible to do so. Further, the rotating body 10 is provided with a linear slide 12 that is moved in the vertical direction by a drive device (not shown), and a suction tube holder 14 is fixed to this linear slide 12. A suction nozzle 18 is rotatably supported around a vertical axis via a sleeve 20 on an arm portion 16 extending horizontally from the lower end of the suction tube holder 14 .

The suction nozzle 18 includes a main body 22 fitted into the sleeve 20 so as to be non-rotatable and movable in the axial direction, and a suction tube 24 fitted integrally with the main body 22. Adsorption tube 2
4 is fixed to the main body 22 by a nut 32, and an air passage 34 is formed in the center thereof. This air passage 34 is connected to a vacuum source (not shown) by connecting a vacuum hose 38 to a nut 32 with a connecting fitting 40, and when an electromagnetic directional switching valve provided in the vacuum source is switched, , the suction tube 24 suctions and releases the electronic component 44 at the suction portion 42 at its tip.

Further, a compression coil spring 46 is disposed between the sleeve 20 and the lower end of the main body 22, so that the large diameter portion 48 of the main body 22 is brought into contact with the upper surface of the sleeve 20. As a result, the electronic component 44 is reliably mounted on the printed circuit board 4 with an appropriate pressing force, and the electronic component 44. Damage to the suction nozzle 24 and the like is avoided. The downward stroke of the suction nozzle 18 is set so that the electronic component 44 descends slightly below the position where it contacts the print substrate Fi4, but the suction nozzle 18 compresses the spring 46 and the sleeve 20
By moving relative to the electronic component 44. Adsorption tube 2
4 damage etc. can be avoided.

In addition, the suction nozzle 18 has a large diameter gear 50 provided on the sleeve 20 and a small diameter gear 52. It is rotated together with the sleeve 20 by being rotated by a servo motor 60 via a medium diameter gear 54 and a drive gear 58.

Furthermore, a projector 66 is attached to the lower surface of the arm portion 16 using a plurality of brackets 64. The floodlight 66 consists of a diffuser plate 70 fixed to a light emitter 68 in which a plurality of light emitting elements 67 are buried at regular intervals, and the suction tube 24 is formed in the center of the light emitter 68. The suction portion 42 is slidably inserted into the through hole 78 , and passes through the projector 66 so that the suction portion 42 is located in front of the projector 66 . The light projector 66 emits light when the image pickup bag W (not shown) images the posture of the electronic component 44 sucked by the nozzle 18, and the control device detects the posture error Δθ of the electronic component 44 based on the image taken by the image pickup device. and center position errors ΔX and ΔY. The attitude error Δθ is corrected by rotating the suction nozzle 18.

The printed circuit board support device 2 includes a table 8 that supports the printed circuit board 4, as shown in FIGS. 1 and 2.
0. This table 80 includes an upper frame 82 and a lower frame 84 stacked in the vertical direction,
The NC slide 88 moves the printed circuit board in the X-axis direction parallel to the moving direction and in the Y-axis direction perpendicular to the X-axis direction. The NC slide 88 is equipped with an X-axis slide 90 that is moved in the X-axis direction and a Y-axis slide 92 that is moved in the Y-axis direction, and the table is moved by moving these slides 90° 92 using a servo motor and a feed screw. 80 is positioned at a predetermined position within the horizontal plane.

The NC slide 88 constitutes a moving device.

A pair of guide rods 94 are fixed to the upper frame 82. These guide rods 94 are slidably fitted into the Y-axis slide 92 through an opening 96 provided in the lower frame 84 and extended into an opening 98 provided in the X-axis slide 90. ing. The upper frame 82 has a Y-axis slide 92 by a guide rod 94.
As the guide loft 94 is raised and lowered by the cylinder 99, the lower frame 84. It is moved toward and away from slides 90 and 92. The upper frame 82 is spaced apart from the lower frame 84 and located at the same height as the printed circuit board loading device and the printed circuit board unloading device, and has an elevated position where the printed circuit board is delivered.
It is moved between a certain distance below it and a lowered position where it is in close contact with the lower frame 84 as shown in FIG. 2 and where electronic components can be mounted without interfering with the carrying-in device and the carrying-out device. It is.

The upper frame 82 also includes, as shown in FIG.
A fixed support member 100 that supports the printed circuit board 4 at both edges parallel to the feeding direction. Movable support member 102. Main positioning member 10 that accurately positions the printed circuit board 4
4. A sub-positioning member 106 is provided. These fixed support members 100, movable support members 102. The main positioning member 104 and the sub-positioning member 106 are
It has the same configuration as that described in Japanese Patent No. 168299, and will be briefly explained here.

The fixed support member 100 includes a fixed bracket 110 and a fixed guide 112 supported by the bracket 110 at both ends of one of the two sides of the upper frame 82 parallel to the printed circuit board feeding direction. The movable support member 102 is attached to both ends of the other side of the upper frame 82 and includes slides 114 movable in the Y-axis direction and a movable guide 116 supported by the slides 114. Each of the slides 114 is immovably engaged with the upper frame 82 by a clamp mechanism (not shown), and is released from the engagement by a clamp release mechanism, allowing movement in the Y-axis direction. It is moved as the widths of the loading device and the unloading device are adjusted, so that the distance between the movable guide 116 and the fixed guide 112 is adjusted in accordance with the width of the printed circuit board 4.

In addition, the main positioning member 104 and the sub-positioning member 10
6 has positioning pins 120° and 122 that fit into positioning holes provided in the printed circuit board 4, respectively, and the main positioning member 104 is fixed to the upper frame 82, while the sub-positioning member 106 is movable. It is set in. The sub-positioning member 106 is fitted into a guide rail 124 provided on the Y-axis slide 92, and is always immovably engaged with the guide rail 124 by a clamp member (not shown), but when the clamp member is not clamped by the clamp member. The clamp is released and held in a fixed position by a clamp release member (not shown) provided on a fixing member separate from the printed circuit board support device.
By moving the upper frame 82 in the X-axis direction while being held by the clamp release member, its position can be changed to match the position of the positioning hole of the printed circuit board 4. In addition, 126 is a positioning pin,
This is provided for positioning a support jig that supports from below the center portion of the printed circuit board 4 whose both ends are supported by the fixed support member 100 and the movable support member 102.

The lower frame 84 is provided to be movable in the vertical direction relative to the Y-axis slide 92, and a height adjustment device 128 for adjusting the height of the table 80 is provided between the lower frame 84 and the Y-axis slide 92. It is provided.

As shown in FIG. 1, a pair of guide rods 130 are fixed to the lower frame 84 so as to extend downward, and the guide rods 130 are fitted into the Y-axis slide 92 so as to be slidable in the axial direction. has been done. Lower frame 84
is engaged with the Y-axis slide 92 by a guide rod 130. The lower frame 84 also includes
Four through holes 132 (see FIG. 2) are provided that extend in the vertical direction, and four screw members 134 erected on the Y-axis slide 92 are inserted into each through hole 132, respectively. A compression coil spring 140 is disposed between a large diameter flange portion 136 provided at the upper end of the screw member 134 and a spring receiver 138 fixed to the lower surface of the lower frame 84, and the lower frame 84 is connected to the Y-axis slide 92. It is biased in the direction of approaching.

As shown in FIG. 2, the lower frame 84 is further provided with bottomed holes 144 that open downward at positions adjacent to the four locations where the compression coil springs 140 are disposed. A piston 146 is fitted airtightly and slidably in the axial direction. A piston rond 148 of this piston 146 is connected to a through hole 15 provided in a guide member 150 fixed to the lower surface of the lower frame 84.
2 so as to be slidable in the axial direction. This guide member 150 is loosely fitted into a bottomed hole 154 provided in the Y-axis slide 92 and opened upward, and is inserted into the piston rond 14B.
The lower end of the plate 156 is fixed to the bottom of the bottomed hole 154.
Supported by

The lower frame 84 is provided with four passages 160 that communicate the air chamber 158 formed between the bottom of each of the four bottomed holes 144 and the piston 146 with the outer surface of the lower frame 84. An air supply device (not shown) is connected to each passage 160. - The air supply device is provided with an electromagnetic directional switching valve, and by switching the switching valve, the four air chambers 158 are simultaneously communicated with the air supply device or the atmosphere. Air chamber 158
is in communication with the atmosphere, the lower frame 84 is biased by the spring 140, and the spring receiver 138 is in contact with the atmosphere.
It is positioned in a lowered position abutting the shaft slide 92.

Further, when air is supplied to the air chamber 158, the lower frame 84 is raised against the biasing force of the spring 140. This upward movement is restricted by the guide member 150 and the piston 146 coming into contact with each other.

As the lower frame 84 is raised and lowered, the upper frame 82 placed thereon is raised and lowered, and the table 8
0 relative to the Y-axis slide 92, the vertical position of the printed circuit board 4 supported by the upper frame 82 is changed. 4 compression coil springs 140. Piston 146. The air chamber 158 and the like and the air supply device constitute the height adjustment device 128, and in this embodiment, the adjustment distance, that is, the distance between the raised position and the lowered position, is 31 m.

Incidentally, as shown in FIG. 1, adjustment bolts 162 are screwed into the four corners of the upper frame 82 so that the vertical position of the table 80 can be finely adjusted. If the table 80 is tilted in the horizontal plane or the height of the table 80 is inappropriate, loosen the appropriate lock nut 164 and rotate the adjustment bolt 162 to adjust the table 80 to be horizontal. It is.

In addition, in this example, the electronic component mounting location is such that the carrier tape holding the electronic component is fed one pitch at a time along the longitudinal direction, and the top surface position of the electronic component is almost constant regardless of its height. It is designed to be supplied to the electronic component holding device in the same state.

In the electronic component mounting device configured as above,
The height of the table 80 is adjusted in advance according to the height of the electronic component 44 to be mounted. When mounting a low-height electronic component, for example, 0.4 to 1.2H, on the printed circuit board 4, the table 80 is placed in the raised position, and a high-height electronic component, for example, a 6fl electronic component, is mounted on the printed circuit board 4. When it is mounted on the printed circuit board 4, it is placed in the lowered position.

Then, the electronic component holding device 8 receives the electronic component 44 from a component supply device (not shown), and mounts the electronic component 44 on the printed circuit board 4 after the position of the electronic component 44 is detected by the imaging device. After the image is captured by the imaging device, the attitude error Δθ is corrected before the image is moved onto the printed circuit board 4, and
In the printed circuit board support device 2, the NG slide 88 is moved, and with the center position errors ΔX and ΔY corrected, the electronic component mounting portion of the printed circuit board 4 is positioned directly below the suction nozzle 18. Ru.

The suction nozzle 18 is positioned directly above the electronic component mounting location on the printed circuit board 4 and is lowered to remove the electronic component 4.
4 to the printed circuit board 4.

At this time, the position of the table 80 is adjusted according to the height of the electronic component 44, and if the electronic component 44 is small in height, it is in the raised position and the position between the printed circuit board 4 and the suction nozzle 18 is adjusted. If the distance is small and the electronic component 44 is tall, it is in the lowered position and the distance becomes larger. It remains almost constant regardless of height. Therefore, when the electronic component 44 is mounted on the printed circuit board 4, the spring 46 is compressed and a pressing force is applied to the electronic component 44, but even if the electronic component 44 is tall, the pressing force is (This prevents damage to the electronic components 44, etc., and avoids displacement of the electronic components 44 due to vibrations of the printed circuit board 4.

Note that in the above embodiment, the table 80 was adjusted to two positions, the raised position and the lowered position.
It may be possible to make the adjustment more finely in multiple steps (or it may be possible to make the adjustment steplessly).

Further, in carrying out the method according to the present invention, instead of adjusting the height of the printed circuit board, the height of the suction nozzle (lowering start position) may be adjusted. By doing so, for example, when the suction nozzle suctions electronic components of different heights that are placed on the bullet and supplied,
Damage to electronic components can be avoided. By adjusting the height of the suction nozzle, the distance between the suction nozzle and both the pallet and the printed circuit board can be changed at once, and damage to electronic components can be avoided. Further, the heights of both the printed circuit board and the suction nozzle may be adjusted.

Further, in the apparatus and method according to the present invention, the printed circuit board supporting device supports the printed circuit board at a fixed position without moving the table in the X-axis direction or the Y-axis direction, and the electronic component holding device However, an electronic component mounting device or an electronic component holding device configured so that the suction nozzle is moved in a direction parallel to the board surface of the printed circuit board and positioned directly above the electronic component mounting location is not suitable for electronic component mounting. An electronic component mounting device other than the above-mentioned examples, such as an electronic component mounting device in which a suction nozzle that has absorbed electronic components is moved to an electronic component mounting location and lowered to mount the electronic component on a printed circuit board, and mounting of electronic components using the device It can be applied to

In addition, although not illustrated individually, the present invention can be implemented with various modifications and improvements made to the height adjustment device and the like based on the knowledge of those skilled in the art.

[Brief explanation of drawings]

FIG. 1 is a front view (partially) showing a printed circuit board support device of an electronic component mounting apparatus which is an embodiment of the device according to the present invention, and FIG. 2 is a plan view. FIG. 3 is a front view (partially) showing the electronic component holding device of the electronic component mounting device. 2 Niblint board support device 4 Niblint board 8: Electronic component holding device 18: Suction nozzle 44; Electronic component 46: Compression coil spring 80: Table 82: Upper frame 84: Lower frame 128: Height adjustment device 140: Compression coil spring

Claims (2)

[Claims] (1) A method of lowering the suction nozzle that has suctioned the electronic component and mounting the electronic component on the electronic component mounting location of the printed circuit board, in which case the height of the electronic component is high, the suction nozzle is lowered to the lowering start position of the suction nozzle. The distance from the printed circuit board is increased, and when the height of the electronic component is low, the distance is decreased, so that the descending distance of the suction nozzle for mounting the electronic component on the printed circuit board can be adjusted regardless of the height change of the electronic component. An electronic component mounting method characterized by keeping the temperature substantially constant. (2) An electronic component holding device equipped with a suction nozzle that is lowered while sucking the electronic component using a vacuum and attaches the electronic component to the electronic component mounting location on the printed circuit board; and a printed circuit board support that supports the printed circuit board with a table. In the electronic component mounting apparatus, the table is provided to be movable in the vertical direction, and
An electronic component mounting device characterized by being provided with a height adjustment device for adjusting the height of the table.