JPH0451600A - Mounting method for component - Google Patents

Abstract

PURPOSE:To accurately mount a component on a prescribed position by executing a simple image processing operation and to enhance a mounting efficiency by a method wherein the position of the component in a sucked state is recognized, a mounting position on a circuit board is recognized on the basis of information on the position, the dislocation from the sucked state of the component is corrected again and the component is mounted. CONSTITUTION:A suction nozzle 5 is moved to the upper part of an electronic component 1 placed on a feed position; images of the shape, the lead position and the brightness of the electronic component 1 are picked up, through the suction nozzle 5 and a light-transmitting sheet 10, by using a recognition camera 25; the images are stored. Then, the lowered suction nozzle 5 sucks the electronic component 1; after that, it is moved to and stopped on the upper part of a prescribed mounting position on a circuit board 4. Then, a window 29a is set while the position of a lead la stored on a picked-up picture 29 is used as the center. Then, a focus is adjusted on the surface of the circuit board 4; the position of an electrode 4a on the circuit board 4 is recognized by using the recognition camera 25. After that, a dislocation amount is computed from the position of the detected electrode 4a and the position of the lead terminal la. While the position of the movement table 22 and the direction of the suction nozzle 5 are being corrected, the lead terminal la is positioned accurately and mounted on the electrode 4a.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a component mounting method for mounting electronic components held by suction onto a circuit board.

(Prior Art) A conventional component mounting method for mounting electronic components onto a circuit board will be described with reference to FIG.

FIG. 5 is a block diagram for explaining a conventional component mounting method, in which the electronic component 1 placed at a predetermined supply position by a component supply device (not shown) is transferred to a component mounting device (not shown). The attached suction nozzle 2 attracts and moves above the recognition camera 3. After detecting the position of the electronic component 1 that has been sucked by the recognition camera 3, the suction nozzle 2 is moved to a position opposite to the component mounting position on the circuit board 4, and the positional deviation of the electronic component 1 is corrected and the circuit board 4 is placed in a predetermined position. It was installed in position.

(Problem to be Solved by the Invention) However, in the above-described mounting method, while the suction nozzle 2 that has suctioned the electronic component 1 is moving toward the circuit board 4, the suction nozzle 2 is accurately positioned above the recognition camera 3. Because of the need for positioning, there was a problem that the cycle time was long and efficiency was low.

In addition, although the positional deviation between the suction nozzle 2 and the electronic component 1 is corrected, since the mounting position of the circuit board 4 on which the electronic component 1 is mounted is not recognized, the circuit pattern formation error 1 circuit board 4
Due to positioning errors, etc., and during installation,
For example, there is also the problem that components are not accurately mounted at predetermined mounting positions on the circuit board due to misalignment caused by the adhesive.

Therefore, after the parts are mounted, there is a problem in that an external appearance inspection process is required to confirm the mounted state of the parts using another special machine or by visual inspection.

As a countermeasure to this problem, there is a method of arranging a recognition camera on the second side of the suction nozzle to recognize the reference mark or mounting device on the circuit board 4, but since the operation of accurately positioning the recognition camera and recognizing it is added, the cycle time is increased. There is a problem that it is long, and there is also a relative positional error between the recognition camera and the suction nozzle, and there is a problem that there is a possibility that the parts will be installed out of position.

The present invention solves the above problems and provides a component mounting method that allows components to be accurately mounted in a predetermined position by simple image processing and has high mounting efficiency.

(Means for Solving the Problems) In order to solve the above problems, the present invention captures an image of a supplied electronic component in a state of good contrast through a suction nozzle made of a transparent material, and calculates the position of the characteristic part of the component. Next, after picking up the component with the suction nozzle, a window is set around the position of the characteristic part of the component shape calculated above from the screen imaged at the component mounting position on the board, and the window is set to be centered on the position of the characteristic part of the component shape, which is influenced by the complex background of the board. This method detects the position of the characteristic part of the component again within the window, recognizes the mounting position of the component on one circuit board, corrects the positional deviation, and mounts the component.

(Function) With the above configuration, the position of the component in the suction state is recognized, and then the mounting position is recognized on the mounting position of the circuit board based on the recognized position information, and the component is returned to the suction state. Since the parts are mounted after correcting the positional deviation between them, the parts can be mounted accurately with simple image processing.

(Example) An example of the present invention will be described with reference to FIGS. 1 to 4.

FIG. 1 is a sectional view of a suction nozzle section of a component mounting apparatus used in the present invention.

In the figure, a nozzle holder 6 holding a suction nozzle 5 with a suction port protruding from the center of a transparent disk is prepared to correspond to the size of an electronic component (not shown) to be suctioned. , is detachably attached to the lower end of the suction cylinder 7 by means of an elastic locking member 8.

The suction cylinder 7 has the above-mentioned suction nozzle 5 and a fixing nut 9 attached above.
A suction chamber 11 is formed by the light transmitting plate 10 attached thereto.

The suction tube 7 also has an elastic locking tool 13 attached to the lower end of the rotary tube 12 so that it can be easily replaced when the inside of the suction chamber 11 becomes dirty.
It is removably attached.

The rotary cylinder 12 is rotatably supported by a bearing box 17 fixed to a lifting table 16 via ball bearings 14 and 15 fitted to the upper and lower parts thereof.

A plurality of suction holes 7a are formed in the peripheral wall of the suction tube 7 at approximately the center of the suction chamber 11, and a plurality of ventilation holes 7b and 7c are formed near the transparent plate 10 at appropriate intervals in the local direction. On the other hand, an annular groove 18a communicating with the suction hole 7a is provided on the inner peripheral surface of the suction outer cylinder 18 fixed to the lifting platform 16, into which the outer circumference of the suction cylinder 7 is rotatably fitted. Mutually independent arcuate grooves 18b and 18c are formed which communicate with the above-mentioned ventilation holes 7b and 7c, and a suction port 18d, an air blowing port 18e and an air suction port 18f open on the outer peripheral surface of the suction outer cylinder 18, respectively. is connected to. Furthermore, O-rings 9 and 20 for sealing are arranged on the outer periphery of the suction cylinder 7 on both sides of the suction hole 7a.

Note that the air passing from the air inlet 18e to the air inlet 18f forms an air curtain along the surface of the transparent plate 10.

The rotating cylinder 12 is rotated by a drive device (not shown) via a pulley 21 fixed to the upper end. Further, the above-mentioned elevating table 16 is movable up and down by a guide 23 provided on a movable table 22 that can be raised and lowered to move between a predetermined component supply position and the circuit board, and is supported by a tension coil spring 2.
4 and is elastically supported.

The recognition camera 25 adjusts the position of the optical system barrel 28 in the optical axis direction using a feed screw 27 which is disposed coaxially above the rotary cylinder 12 and is driven by an electric motor 26. It has an automatic focusing mechanism combined with a focus detection means.

In this example, focusing was performed by moving the lens barrel 28, but as shown in FIG.
The recognition camera 25 may be moved in the optical axis direction.

Next, a component mounting method using the suction nozzle 5 configured as described above will be explained. First, as shown in FIG. 3, the suction nozzle 5 is moved above the electronic component 1 placed at the supply position of a component supply device (not shown), and the recognition camera 25 detects the suction nozzle 5 and the transparent plate 10. The shape, lead position, and brightness of the electronic component l are imaged and memorized through the camera. At this time, if the background on which the electronic component 1 is placed is uniform, the image can be taken relatively easily. The recognition method using imaging is as follows:
Since it is described in detail in the specification of Japanese Patent Application No. 170038/1982, its explanation will be omitted.

Further, the recognition camera 25 focuses on the top surface of the electronic component 1 by an automatic focusing device, images the electronic component 1 with high contrast, and detects the plurality of lead terminals 1a with high accuracy. Note that if the recognized shape of the electronic component 1 is inappropriate, the adjoining electronic component 1 is directly sent to the supply position without entering into the suction operation, and the recognition camera repeats the above-mentioned operation again to take an image and store it.

Next, the suction nozzle 5 descended together with the moving table 22.
After picking up the electronic component 1, it rises again, moves horizontally, and stops the picked up electronic component 1 above a predetermined mounting position of the circuit board 4 (not shown).

Next, moving to FIG. 4, a window 29a is set centered on the position of the lead terminal 1a stored on the screen 29 captured by the recognition camera 25. That window 29a
Edge detection is performed inside the terminal, and the position of the lead terminal 1a is reconfirmed. Note that, at this time, if the brightness of the lead terminal 1a that has already been stored is referred to, even more accurate recognition can be performed.

Next, the automatic focusing device focuses on the upper surface of the circuit board 4, and the recognition camera 25 recognizes the position of the electrode 4a of the circuit board 4 where the electronic component 1 is to be mounted. After that, the amount of positional deviation is calculated from the detected positions of the electrodes 4a of the circuit board 4 and the lead terminals 1a of the electronic component 1, and
While correcting the position of the suction nozzle 5 and the direction of the suction nozzle 5, the moving table 22 is lowered and
is accurately positioned and mounted on the electrode 4a of the circuit board 4.

By repeating the above movement, appropriate electronic components 1 are sequentially and efficiently mounted at the electronic component mounting positions on the circuit board 4.

In the above explanation, the position of the lead terminal 1a is memorized before the suction nozzle 5 suctions the electronic component l, but it may also be memorized after suction. may be stored and a window 29a may be set on the electrode 4a on the circuit board 4.

(Effects of the Invention) As explained above, according to the present invention, the recognition camera disposed on the same axis as the suction nozzle not only recognizes the electronic component at the supply position and corrects its position. Since the electrodes at the mounting position of the circuit board can be recognized and the positional deviation with respect to the electronic component being sucked can be corrected, a component mounting method can be obtained that allows accurate mounting at all times with relatively simple image processing. In addition, the suction nozzle only moves between the supply position and the mounting position, so there is no need to stop in between.

A highly productive component mounting method that significantly reduces cycle time can be obtained.

[Brief explanation of drawings]

1 and 2 are a cross-sectional view of the suction nozzle used in the present invention and a cross-sectional view of main parts showing another automatic focusing device,
FIG. 3 is a perspective view showing the state before electronic components are picked up, FIG. 4 is a plan view showing the state in which the components are imaged on the board, and FIG.
! ! is a configuration diagram showing a conventional mounting operation. 1...Electronic component, 1a... Lead terminal, 2.
5... Suction nozzle, 3,25... Recognition camera,
4...Circuit board, 4a...Electrode, 6...
Nozzle holder, 7...Suction cylinder, 7a...Suction hole, 7b...Vent hole, 8゜13...Elastic locking tool,
9...Fixing nut, lO...Transparent plate, 11...
- Suction chamber, 12... Rotating tube, 14.15... Ball bearing, 16... Elevating table, 17... Bearing box, 18... Suction outer cylinder, 18a... Annular groove, 18b , 18c...
Arc-shaped groove, Lad...suction port, 18e...air inlet, 18f...air inlet, 19.20...0
Ring, 21...Pulley, 22...Moving table,
23...Guide, 24...Tension coil spring, 26.
...Electric motor, 27... Feed screw, 28... Optical system barrel, 29... Imaging screen, 29a... Window patent applicant Matsushita Electric Industrial Co., Ltd.

Claims (2)

[Claims] (1) After capturing an image of an electronic component through a suction nozzle made of a transparent material and memorizing the position of its characteristic parts, the component is suctioned and moved above the mounting position on the circuit board, and is memorized on the imaging screen. The window is set around the position of the above-mentioned characteristic part on the circuit board, and then the position of the characteristic part on the circuit board is recognized, the position is detected, the positional deviation with the window is corrected, and the potential component is installed. Characteristic parts mounting method. (2) The component mounting method according to claim (1), wherein after the component is suctioned by a suction nozzle, an image is taken and the position of a characteristic part of the electronic component is stored.