JP2001210997A - Device for mounting electronic part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for mounting an electronic part which can reduce an error of detecting the position of an electronic part and has a simple structure. SOLUTION: While each mounting head 7 moves above each part supply unit storing an electronic part to be mounted, a motor 22 for selecting each nozzle is energized, the head 7 is turned such that the tip of a nozzle 21 for the part faces down, and a cam follower 34 is fitted in a cutaway portion before the head 7 is lowered to take out the part by driving a motor for driving a vertical shaft. The opening 37 of a nozzle mounting part 26 communicates with a vacuum source and chucks and takes out the part from the part supply unit. Next, while the head 7 is moved to a position above a substrate P, the head 7 is turned 90 degrees by the motor 22 and a moving camera takes a photograph and recognizes the position. When the motor 22 is driven, a cam 33 is also rotated with a horizontal shaft 20 and the nozzle 21 is turned 90 degrees in a state where it communicates with vacuum source and chucks the part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component mounting apparatus in which a mounting head takes out an electronic component from a component supply unit and mounts the electronic component on a printed circuit board.

[0002]

2. Description of the Related Art Such an electronic component mounting apparatus is disclosed in, for example, JP-A-6-177593, in which a component position recognizing camera is mounted on a component mounting section that moves in a horizontal direction in order to shorten a component mounting cycle time. A technique for recognizing a position by a recognition camera during movement of a component mounting unit is disclosed.

[0003]

However, since the reflector required for position recognition is moved at the time of recognition,
Since there are moving parts, errors in component position recognition may occur,
The structure was also complicated. Therefore, the present invention provides an electronic component mounting apparatus having a smaller recognition error and a simpler structure than those having a movable part.

[0004]

According to the present invention, there is provided an electronic component mounting apparatus in which a mounting head takes out an electronic component from a component supply unit and mounts the electronic component on a printed circuit board. A component suction nozzle is provided to enable the mounting head to move in the horizontal direction and to move up and down, to be rotatable around a vertical line and a horizontal line, and to be provided to the mounting head when the mounting head rotates around the horizontal line. The cam follower provided on the nozzle holder is guided along the cam surface of the cam so that the nozzle can be moved toward and away from the center of the mounting head.

The present invention further comprises a lock mechanism for preventing the rotation of the cam, and when the mounting head rotates around a horizontal line in order to select a suction nozzle to be used, the rotation of the cam is controlled by the lock mechanism. When the suction nozzle moves away from the center of the mounting head and descends to take out the electronic component, the nozzle is communicated with a vacuum source, and the position of the electronic component sucked by the suction nozzle is recognized by the recognition camera. When the mounting head rotates around the horizontal line, the blocking by the lock mechanism is released and the cam also rotates so that the nozzle is moved to the recognition position of the camera while the nozzle is connected to the vacuum source. It is something to do.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of an electronic component mounting apparatus 1. On a base 2 of the apparatus 1, there is provided a component supply unit 3 for supplying various electronic components to a component pick-up unit (component suction position 10 described later) one by one. Are arranged side by side. A supply conveyor 4, a positioning unit 5, and a
And a discharge conveyor 6. Supply conveyor 4
Transports the printed circuit board P received from the upstream to the positioning unit 5, and after the electronic components are mounted on the substrate P positioned by the positioning mechanism (not shown) by the positioning unit 5, the printed circuit board P is transferred to the discharge conveyor 6.

In FIG. 1, a mounting head 7 and the like, which will be described later, are omitted, but above the substrate P and the component supply unit 3, as shown in FIG. The mounting head 7 and its driving mechanism are provided. The mounting head 7 and the like will be described below.

Reference numeral 8 denotes a beam which is long in the X direction, and moves in the Y direction along the pair of guides 9 above the printed board P and the component suction position 10 of the component supply unit 3. Suction position 1
0s are arranged on a straight line parallel to the X axis.

FIG. 3 (side view in the direction of arrow A in FIG. 1)
As shown in FIG. 2, two X-moving units 13 which are individually moved along the guide 12 by the X-axis linear motor 11 in the longitudinal direction, that is, the X-direction, are provided (only one is shown in the drawing). Each X moving unit 13 has a mounting head 7
An up / down motor 14 is mounted to move the head block 15 up and down. The rotation of the motor 14 causes the head block 15 to move up and down. The mounting head 7 is attached to the block 15 so as to be rotatable around a vertical axis via a bearing 17 by an angle correction axis motor 16. The mounting head 7 is rotatably mounted together with a horizontal shaft 20 on a holder 19 (not shown in FIG. 3) fixed to a shaft 18 rotated by the correction shaft motor 16 as shown in FIG. 4 (schematic side view). ing.

Accordingly, the two mounting heads 7 are individually movable in the X direction, are rotatable around the vertical line, are vertically movable, and are movable together in the Y direction.

Next, the mounting head 7 and the like will be described in detail with reference to FIGS. The mounting head 7
Comprises a horizontal shaft 20, a nozzle mounting portion 26 to which each nozzle 21 is mounted, and a nozzle holder 27 to which the mounting portion 26 is mounted. Six suction nozzles 21 are provided radially on the outer periphery of each mounting head 7 at intervals of 60 degrees. The six nozzles 21 are basically different types, and are selected and used in accordance with different types of components having different sizes and the like. However, the number of the nozzles 21 is not limited to six, and Less or more may be provided.
That is, the nozzle selecting motor 22 provided in the holder 19
, The mounting head 7 is rotated, and the selected nozzle 21 is directed downward so that the electronic component 24 can be sucked.

More specifically, a disc-shaped reflecting plate 25 is fixed to an intermediate portion of each nozzle 21, and the nozzle 21 is a hollow nozzle mounting portion slidable in a guide portion of the horizontal shaft 20. 26 is also provided so as to be detachable while being locked by the locking member 23. Then, the horizontal shaft 20 and the nozzle holder 27
A spring 28 for urging the two to separate from each other is provided. Numerals 31 and 32 denote nuts and rails, which together constitute a linear guide. When the horizontal shaft 20 rotates, the rails 32 provided on each nozzle holder 27 are mounted on the nut mounting portion 30 of the horizontal shaft 20. Nut 31
As the cam follower 34 is guided along the cam surface of the cam 33, the nozzle holder 27 and the nozzle 21 approach or move away from the center of the cam 33.

That is, in a state where a lock mechanism described later is operated and locked, when the nozzle selecting motor 22 is energized, a cam 33 provided around the horizontal shaft 20 which rotates through the bearing 29 when the nozzle selecting motor 22 is energized. Spring 2 along the cam surface
8 causes the mounting head 7 such as the nozzle holder 27 to rotate while the cam follower 34 provided at the side end of the nozzle holder 27 is pressed.

In this case, as shown in FIG. 5, when the nozzle 21 selected by driving the nozzle selecting motor 22 is directed downward and comes to the component suction position 10, the surface position of the cam surface is at the lowest position, The selected suction nozzle 21 is lowered so that the communication opening 37 formed at the end of the nozzle mounting portion 26 can communicate with the vacuum path 36 of the horizontal shaft 20. In addition, the cam follower 34 fits into the notch 42 of the cam 33, and the position is reliably fixed.

Therefore, the opening 37, the vacuum passage 36, the passage 38
The vacuum circuit for suctioning the components of the nozzle 21 is connected to a vacuum source (not shown) through the like.

Numeral 39 is a sealing material made of rubber, and numeral 40 is an air cylinder which constitutes a lock mechanism. When the cylinder is operated, a rod 41 pierces the opening of the cam 33 and the nozzle selecting motor 22 is driven to drive the bearings 29, 35. The cam 33 does not rotate even if the horizontal shaft 20 rotates through the shaft. If the rod 41 does not pierce, the cam follower 34 is pressed against the cam surface 10 of the cam 33 by the spring 28 as described above. The cam 33 also rotates. For this reason, the component suction nozzle 21 is moved to the component suction position 1 through the opening 37, the vacuum path 36, the passage 38, etc., while the component suction vacuum circuit of the nozzle 21 is connected to the vacuum source.
Since the area within 90 degrees from 0 to the part recognition position is in a vacuum suction state, the part does not fall from the nozzle 21.

Although the lock mechanism is constituted by the air cylinder 40 as described above, the invention is not limited to this. The lock mechanism may be constituted by an electromagnetic solenoid or other means.

Also, as shown in FIG.
A mobile camera 45 for component position recognition is suspended from the mounting frame 46 via a mounting frame 46, and its optical axis is oriented in the horizontal direction. That is, the moving camera 45 is provided for each X-axis moving unit 13, and moves with the mounting head 7 when the moving unit 13 moves. The camera 45
The position of the electronic component 24 is recognized with respect to the XY directions and the rotation angle by how much the electronic component 24 is sucked and held with respect to the nozzle 21.

An embodiment in which various sensors are provided as shown in FIGS. 8 and 9 will be described. First, arms 47 are fixed to both ends of the mounting frame 46 of the mobile camera 45,
A pair of component presence / absence detection sensors 48 (the front side sensor is omitted in FIG. 9 but the back side sensor is shown) is attached to the arm 47. The sensor 48 detects the presence / absence of an electronic component (whether or not it is attracted to the nozzle 21) depending on whether or not the other light receiving element receives a light beam emitted from one of the light emitting elements. Such an optical sensor will be referred to as a light emitting / receiving sensor. This light beam passes through the position of the black circle on the electronic component 24 in FIG. 9 and detects the absence of the component when it is blocked by the component 24 and the light receiving element does not receive light.

In this detection operation, the suction nozzle 21 takes out the electronic component 24 from the component supply unit 3 and
Is performed in parallel with the imaging by the camera 45 when the nozzle 21 is stopped facing the moving camera 45 by the 90-degree rotation. If there is no component 24, the subsequent mounting operation is not performed. Although it is conceivable to detect the presence or absence of a component by taking an image of the camera 45, it is not easy to determine the presence or absence of a component from an image, so the sensor 48 is used.

Further, a sensor for detecting the length of the suction nozzle 21 is provided at the position of a black circle 49 in FIG. This sensor also
In the above-mentioned light emitting / receiving sensor, a black circle 49 is a position through which the light beam passes. This sensor detects when the long suction nozzle 21 is erroneously attached to the mounting head 7, and it is abnormal (erroneous attachment) when the long nozzle is attached and the light beam is blocked by the nozzle. Is detected, and the user is notified by a notifying device (not shown). This detection operation is performed before the operation of removing the component 24, and is performed when the power is turned on or after the nozzle is replaced.

Although this sensor is not shown, the arm extends from the mounting frame 46 for mounting the camera 45 in the same manner as the component presence / absence detection sensor 48 in FIG.

A sensor for detecting the presence / absence of the suction nozzle 21 is provided at the position of a black circle 50 in FIG. The reason for this position is to detect the presence or absence of the nozzle 21 at a position where the electronic component 24 can be taken out facing downward. This sensor is also a light emitting / receiving sensor, and a black circle 50 is a position where a light beam passes. Although this sensor is not shown, the arm is extended from the mounting frame 46 for mounting the camera 45 in the same manner as the component presence / absence detection sensor 48 in FIG. This sensor performs the detection operation not at the time of the normal component removal and mounting operation, but after the replacement operation of the nozzle 21 in the mounting head 7 with the nozzle 21 not present in the head 7 or the like. That is, although the replacement nozzle 21 is stored in the nozzle stocker 51 (see FIG. 1) on the base 2, the replacement nozzle 21 is mounted on the head 7 despite the fact that the new nozzle 21 is mounted on the head 7. The sensor is used to judge that there is no error and to prevent the operation of lowering the mounting head 7 to the nozzle stocker 51 again.

It should be noted that a line sensor may be provided on the arm 47 instead of the component presence / absence detection sensor 48 in FIG. 8 to determine not only the presence / absence of the component but also the quality of the component suction attitude. No. 5,539,977 (owned by the applicant).

The operation of the above configuration will be described below.

First, the printed circuit board P is conveyed from an upstream device to a positioning section 5 via a supply conveyor 4 by a conveyor (not shown), and is positioned and fixed by a positioning mechanism.

Next, the electronic component 24 to be mounted by the suction nozzle 21 is determined by a predetermined component according to the mounting data in which the XY coordinate position where the printed circuit board P is to be mounted, the rotation angle position around the vertical axis, and the component type are specified. The nozzle 21 of each mounting head 7 simultaneously sucks and takes out the electronic component 24 at the same time.

That is, each mounting head 7 moves so as to be positioned above each component supply unit 3 accommodating the electronic component 24 to be mounted. In the Y direction, the beam 8 moves along a pair of guides 9, In the X direction, two X moving units 13 are driven along the guide 12 by driving the X axis linear motor 11.
Move respectively.

Since each of the predetermined supply units 3 has already been driven and the components can be taken out at the component suction position 10, each of the upper and lower shaft motors 14 is driven to lower each of the head blocks 15 and the nozzles 21 thereof. Also descends and is sucked out. In this case, each mounting head 7 is energized by the nozzle selection motor 22 so that the nozzle 21 corresponding to the electronic component 24 to be taken out is directed downward, and the rod 41 of the air cylinder 40 Each mounting head 7 rotates while the cam follower 34 is pressed by the spring 28 along the cam surface of the cam 33 which is in a stationary state by being pierced into the cam 33, and used before descending for component removal by driving the vertical motor 14. Each of the nozzles 21 to be selected is already selected and directed downward, and the cam follower 34 is fitted in the notch 42 and the position is determined. Therefore, as shown in FIG. 5, an opening 37 formed at the upper end side of the hollow nozzle mounting portion 26 can communicate with the vacuum passage 36, and the nozzle 21 of each mounting head 7 is The parts are connected to a vacuum source, and the parts are vacuum-sucked and taken out of each part supply unit 3.

Next, each vertical shaft motor 14 is driven to raise the head block 15 and the nozzle 21, the beam 8 moves along a pair of guides 9 in the Y direction, and the X-axis linear motor 11 moves in the X direction. When each X moving unit 13 moves along the guide 12 by driving, each mounting head 7
Moves to a position above the printed circuit board P. During this movement, as shown in FIG.
Each mounting head 7 is rotated by 90 degrees, the light from a light source (not shown) is reflected by the reflector 25, and the transmitted image is captured by the moving camera 45, and how much the electronic component 24 is displaced with respect to the nozzle 21 XY
The position is recognized for the direction and the rotation angle.

The rod 41 of the air cylinder 40 of the lock mechanism is pulled out of the opening of the cam 33 before the mounting head 7 is rotated by 90 degrees by the nozzle selecting motors 22 at the time of position recognition. Therefore, when the motor 22 is driven, the cam follower 34 is pressed against the cam 33 by the spring 28, so that the cam 33 rotates together with the horizontal shaft 20. Therefore, a switching valve (not shown) for connecting or not connecting to a vacuum source (not shown) is provided for each head 7 by one.
The nozzle 21 that has provided the component and sucked the component
7, via a vacuum path 36, a path 38, a switching valve, etc.
While maintaining the suction state of the electronic components by communicating with the vacuum source,
It will rotate 90 degrees (see FIG. 11).

When the nozzle 21 is stopped facing the moving camera 45 by the rotation of the mounting head 7 by 90 degrees, the presence / absence of an electronic component is detected by the component presence / absence detection sensor 48 (whether or not the nozzle 21 is attracted). Is performed in parallel with the imaging by the camera 45, and if there is no component 24, the subsequent mounting operation is not performed.

During the movement of the mounting head 7 before mounting the components on the substrate P, the nozzle selecting motors 22 are driven to rotate the mounting head 7 by 90 degrees in reverse to the recognition operation described above. Then, based on the recognition result, the nozzle 21 moves the beam 8 in the Y direction by the image processing means (not shown) by the amount of the positional shift in the Y direction, and in the X direction by driving the X-axis linear motor 11, and Each angle correction axis motor 16
, The rotation angle position about the X and Y directions and about the vertical axis is corrected.

After this correction, one of the upper and lower shaft motors 14 is driven to lower the head block 15 and the nozzle 2
1, the one part 24 is mounted at a predetermined position on the printed circuit board P, and then the beam 8 moves in the Y direction including the correction amount while the head block 15 is raised by the motor 14, and the other The vertical shaft motor 14 is driven to lower the nozzle 21 of the other mounting head 7 to mount the other component.

In this way, electronic components are mounted one after another in accordance with the mounting data. For example, when the electronic components are taken out from the same component supply unit 3 three times and mounted, the average value of the positional deviation based on the recognition result by the moving camera 45 is calculated. Calculated based on the data stored in the memory (not shown) (data relating to the positional deviation for each time), and at the time of the fourth and subsequent parts removal, FIG.
In the Y direction (the component sending direction, the direction intersecting with the board P transport direction).

That is, as shown in FIG. 12, the position of the tape for accommodating the electronic components in the recess varies depending on the characteristics of each component supply unit 3 at the time of manufacture and the characteristics at the time of attachment of each unit. Accordingly, since all units 3 are not exactly the same in the Y direction at the component suction position 10 in the strict sense, correction is made by the deviation of the average value in the Y direction. The correction is performed by controlling the rotation amount of the mounting head 7 using the nozzle selecting motor 22 when selecting the nozzle 21 to be used. By this correction, the component can be reliably held at the center position of the nozzle 21 by suction. In this case, the amount of rotation of the mounting head 7 may be individually controlled, or one of the mounting heads 7 may be fixed and the amount of rotation of only the other head 7 may be controlled.

When using a nozzle 21 not provided in the mounting head 7, the mounting head 7 is moved in the X and Y directions to
After moving to a place where there is no nozzle of the upper nozzle stocker 51, the mounting head 7 is lowered, the locking member 23 is released, and the unused nozzle 21 is removed from the nozzle mounting portion 26 and placed on the stocker 51. The nozzle 7 is raised and moved above the nozzle 21 to be used, and then lowered to insert a new nozzle 21 into the nozzle mounting portion 26 of the mounting head 7.
And fixed by the locking member 23, and then rises.

Before taking out the component 24 after the nozzle replacement, the length of the suction nozzle 21 is detected by the sensor provided at the position of the black circle 49 in FIG. Abnormal when the light beam is blocked by the nozzle when mounted on the mounting head 7 (wrong mounting)
Is detected, and a user is notified by a not-shown notifying device.

When the replaced nozzle 21 moves downward to a position where the electronic component 24 can be taken out after replacement, a sensor (the position of the black circle 50) detects the presence or absence of the nozzle 21. Since the presence is detected, the operation such as lowering the mounting head 7 to the nozzle stocker 51 when it is determined that the real mounting device 1 is not present despite the replacement new nozzle 21 being mounted on the head 7 You are prevented from doing it again.

In the above embodiment, one mounting head 7 operates only one electronic component 24 at a time. However, a plurality of nozzles are used at one time (up to 6 nozzles).
When a plurality of parts are taken out, transported and mounted on the printed circuit board P, a switching valve for forming and connecting a vacuum path to a vacuum source is provided for each nozzle, and the vacuum path of each nozzle 21 is simultaneously evacuated. It can also be implemented by a mechanism that is connected to the source.

That is, although the mechanical structure is substantially the same as that of the previous embodiment, the control program is changed to operate as follows. First, after one mounting head 7 takes out the component 24 with one suction nozzle 21, the mounting head 7 is raised and the mounting head 7 is rotated so that the other nozzles 21 in the same mounting head 7 are directed downward. After that, the mounting head 7 is lowered to suck the next component 24. In this manner, the components 24 can be sucked by the number of the nozzles 21.

Then, while the mounting head 7 moves to the printed circuit board P, the mounting head 7 is rotated to stop the component 24 sequentially facing the moving camera 45, an image is taken, and the position of the suction nozzle 21 is recognized. Do. This imaging operation may be performed at a time when the mounting head 7 is rotated when the component 24 is taken out and another nozzle 21 component faces the camera 45 in some cases.

Next, the angle of the component 24 sucked by the nozzle 21 facing downward above the printed circuit board P is corrected by the angle correction shaft motor 16 based on the recognition result of the camera 45 in the same manner as in the previous embodiment. The XY direction is corrected by the movement of the beam 8 and the X moving unit 13, and the beam is mounted.

Next, the mounting head 7 is rotated so that the suction nozzle 21 sucking the other component 24 of the same mounting head 7 is directed downward, and the angle correction shaft motor 16 is corrected and the horizontal position is corrected. To position the part,
It is mounted on the printed circuit board P. Other components are sequentially mounted on the board P in the same manner.

[0045]

As described above, according to the present invention,
It is possible to provide an electronic component mounting apparatus in which an error in the recognition of the position of the electronic component is less likely to occur and the structure is simple.

[Brief description of the drawings]

FIG. 1 is a plan view of an electronic component mounting device.

FIG. 2 is a side view of FIG.

FIG. 3 is a side view as viewed in the direction indicated by an arrow A in FIG. 1, showing a state in which electronic components are attracted;

FIG. 4 is a schematic side view of a mounting head and the like.

FIG. 5 is a sectional view of a holder, a mounting head, and the like.

FIG. 6 is a cross-sectional view showing a mounting state of a nozzle.

7 is a diagram showing a cam and a cam follower in FIG. 5;

FIG. 8 is a diagram showing a moving camera and a component presence / absence detection sensor.

FIG. 9 is a diagram showing a mounting position of a mobile camera and each sensor.

FIG. 10 is a side view as viewed in the direction of arrow A in FIG.

FIG. 11 is a diagram showing a vacuum state of a height nozzle at each position of a suction nozzle.

FIG. 12 is a diagram illustrating a Y correction operation when a component is taken out of a suction nozzle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electronic component mounting apparatus 3 Component supply unit 7 Mounting head 8 Beam 11 X-axis linear motor 13 X moving unit 14 Vertical axis motor 15 Head block 16 Angle correction axis motor 19 Holder 20 Horizontal axis 21 Suction nozzle 22 Nozzle selection motor 24 Electronics Parts 26 Nozzle attachment part 27 Nozzle holder 28 Spring 33 Cam 34 Cam follower 36 Vacuum path 37 Opening 38 Passage 40 Air cylinder 41 Rod 42 Notch 45 Moving camera

Claims (2)

[Claims] 1. An electronic component mounting apparatus in which a mounting head takes out an electronic component from a component supply unit and mounts the electronic component on a printed circuit board. The mounting head is provided with a plurality of nozzle holders, and each component suction nozzle is provided. The nozzle is provided along a cam surface of a cam provided on the mounting head when the mounting head is rotated about a horizontal line, and is rotatable about a vertical line and a horizontal line while being movable in a horizontal direction and vertically. An electronic component mounting apparatus characterized in that the nozzle can be moved toward and away from the center of the mounting head by guiding a cam follower provided in the holder. 2. A lock mechanism capable of preventing rotation of the cam is provided. When the mounting head rotates around a horizontal line in order to select a suction nozzle to be used, the rotation of the cam is prevented by the lock mechanism. When the suction nozzle moves away from the center of the mounting head and descends to take out the electronic component, the nozzle is communicated with a vacuum source, and the recognition camera recognizes the position of the electronic component sucked by the suction nozzle. When the mounting head rotates around the horizontal line, the blocking by the lock mechanism is released and the cam is also rotated so that the nozzle is moved to the recognition position of the camera while the nozzle is connected to the vacuum source. The electronic component mounting device according to claim 1, wherein