JPH09326591A - Electronic part mounting device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic part mounting device and a method, wherein various operational errors attendant on an electronic part mounting operation are accurately checked. SOLUTION: A transfer head 10 is equipped with a case 12 possessed of nozzles 14a to 14d. A camera 13 is built in the case 12. The lower ends of the nozzles 14a to 14d are located in the field of view of the camera 13 and obliquely observed by the cameral 13 from above. Only the nozzle 14a selected from the nozzles 14a to 14d is made to project downward. The transfer head 10 picks up an electronic part P from a part feeder, vacuum-sucking it with the lower ends of the nozzles 14a to 14d, and transfers and mounts it on a board 2, wherein the lower ends of the nozzles 14a to 14d and their vicinities are obliquely and properly observed from above, so that three-dimensional perspective picture image data are obtained to check whether an electronic part P is picked up right or mounted right on a board.

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 and an electronic component mounting method for mounting electronic components on a board.

[0002]

2. Description of the Related Art An electronic component mounting apparatus vacuum-adsorbs an electronic component provided in a parts feeder onto a lower end portion of a nozzle of a transfer head, picks it up, and transfers it to a predetermined coordinate position of a substrate positioned by a positioning portion. It is designed to be mounted (for example, JP-A-2-36598 and JP-A-2-36598).
99000 publication).

The operation of transferring and mounting electronic components on a substrate is often performed at a high speed in order to improve productivity, and various work errors occur. Typical examples of this work error are (1) a pick-up error in which the nozzle of the transfer head fails to pick up the electronic component provided in the parts feeder, and (2) the picked-up electronic component is transferred to the substrate. A transfer error in which an electronic component falls from a nozzle on the way, (3) a mounting error in which the electronic component cannot be mounted at a predetermined coordinate position on the substrate in a correct posture, (4) a multi-nozzle type transfer head having a plurality of nozzles in case of,
As the nozzle, the nozzle used for the electronic component to be picked up is selected, only the selected nozzle is projected downward, and the unused nozzle is retreated upward,
Failed to project only the nozzle to be used downward,
There is a nozzle selection error, such as unused nozzles or multiple nozzles accidentally protruding downward.

Conventionally, for example, the following method has been adopted to detect various work mistakes as described above. That is, regarding the above-mentioned pick-up error (1) and transfer error (2), an inspection means such as a camera is provided below the moving path of the nozzle, and the nozzle is observed vertically from below to detect the presence or absence of the error. .

Regarding the above-mentioned mounting error (3), after the nozzle mounts the electronic component on the board and moves from above the board toward the parts feeder, the camera is positioned above the board and the camera is used. The presence or absence of a mounting error was inspected by observing the vicinity of a predetermined coordinate position on the board.

[0006]

However, the conventional techniques cannot detect the work errors (1), (2), and (3) in real time, and the tests (1) and (2) and (3). Since it is not possible to carry out the inspection of (4) by the same inspection device such as a camera, it is necessary to provide a dedicated inspection device for each, and regarding the nozzle selection error of (4), an effective method has not been proposed yet. It is in.

Therefore, it is an object of the present invention to provide an electronic component mounting apparatus and an electronic component mounting method capable of easily inspecting various work errors associated with the electronic component mounting work in real time.

[0008]

According to a first aspect of the present invention, a parts feeder, a positioning portion for a substrate, and electronic parts provided in the parts feeder are vacuum-sucked at a lower end portion of a nozzle to be picked up, and then the positioning portion is provided. An electronic component mounting apparatus comprising: a transfer head that is transferred and mounted on a positioned substrate, wherein the transfer head includes a camera and a plurality of nozzles arranged around the camera so as to be vertically movable. And a lower end portion of the nozzle protruding downward is observed obliquely from above by the camera to obtain a perspective image.

According to a second aspect of the present invention, an electronic component provided in a parts feeder is vacuum-sucked and picked up by a lower end portion of a nozzle of a transfer head, and is transferred and mounted on a substrate positioned by a positioning part. A component mounting method, wherein when a nozzle picks up an electronic component of a parts feeder, during transfer of the picked-up electronic component to a substrate, when mounting the electronic component on the substrate, at least one of after mounting is completed. At the timing, the lower end portion of the nozzle and the electronic component are observed obliquely from above by a camera provided in the transfer head to obtain a perspective image, and the presence or absence of a work error is inspected based on the perspective image.

[0010]

According to the present invention, a three-dimensional perspective image is obtained by observing the vicinity of the lower end portion of a nozzle from an obliquely upper side with a camera at appropriate timing, and various three-dimensional perspective images are obtained based on the perspective image. It is possible to determine whether there is a work mistake.

Next, an embodiment of the present invention will be described with reference to the drawings. 1 is a perspective view of an electronic component mounting apparatus according to an embodiment of the present invention, FIG. 2 is a sectional view of the transfer head, FIG. 3 is a simplified plan view of the transfer head, and FIG. 4 is a control system of the same. Block diagram, Figures 5 (a), 5 (b), 5 (c) and 6
(A), (b), (c) is an image view near the lower end of the nozzle.

First, the overall configuration of the electronic component mounting apparatus will be described with reference to FIG. Reference numeral 1 is a base, and a guide rail 3 as a positioning portion for positioning the substrate 2 is provided at the center of the upper surface of the base. The substrate 2 is conveyed along the guide rails 3 and positioned at a predetermined position. A large number of parts feeders 5 are arranged side by side on both sides of the guide rail 3. The parts feeder 5 includes various types of electronic components.

Y tables 6 are provided on both sides of the base 1, and an X table 7 is installed on the Y table 6. The transfer head 10 is held on the X table 7. The transfer head 10 is driven in the X direction and the Y direction by driving a moving mechanism built in the X table 7 and the Y table 6.
Move horizontally in the direction. A recognition unit 8 composed of a camera is provided between the guide rail 3 and the parts feeder 4.

Next, the structure of the transfer head 10 will be described. In FIG. 2, reference numeral 11 denotes a main body case in which the following elements are assembled. Reference numeral 12 denotes a case provided in the lower center of the main body case 11, and a small camera 13 is built in the center thereof. A plurality of (four in this example) nozzles 14a, 14 are provided around the camera 13.
b, 14c and 14d are stored in a vertical posture (see also FIG. 3). The focal length F of the camera 13 is set near the lower ends of the nozzles 14a to 14d protruding downward.

As shown in FIG. 3, nozzles 14a-14d are provided.
Are arranged on a concentric circle Q centered on the optical axis O of the camera 13. A is the visual field of the camera 13, and all the nozzles 14a to 14d are located in this visual field A. The nozzles 14a to 14d are housed in the case 12 so as to be vertically movable, and vertically moved by a vertically moving means (not shown). Such vertical moving means is well known.

The case 12 is held at the lower end of the rotary shaft 16 of the motor 15, and when the motor 15 is driven, the case 12 rotates in the N direction around the shaft center. By the rotation in the N direction, the nozzles 14a to 14d are selected and the nozzles 14a to 1d are selected.
The position of the electronic component vacuum-adsorbed on the lower end of 4d in the rotational direction is set.

The motor 15 is attached to a hook-shaped bracket 18. A slider 19 is provided on the rear surface of the bracket 18.
Is provided. The slider 19 is fitted on a vertical guide rail 20 provided on the inner surface of the main body case 11. A nut 21 is coupled to the upper portion of the bracket 18. A vertical feed screw 22 is inserted into the nut 21. When the motor 23 is driven and the feed screw 22 rotates, the nut 21 moves up and down along the feed screw 22, which also moves the case 12 up and down.

In FIG. 4, reference numeral 30 is a C for overall control.
A control unit such as a PU. The camera 13 is connected to the control unit 30 via the recognition unit 31. Further, the control unit 30
The light source 25 is controlled via the illumination controller 32, and the motors 15 and 23, the Y table 6 and the X table 7 are controlled via the drive circuit 33.

A ring-shaped mounting body 24 is mounted on the lower portion of the main body case 11, and a light source 25 is mounted on the mounting body 24. The light source 25 includes the light-colored back plate 26 and the nozzles 14 a to 14 d mounted on the lower portion of the case 12.
The illumination light is emitted toward the lower end of the. P is an electronic component mounted on the substrate 2.

This electronic component mounting apparatus has the above-mentioned structure, and its operation will be described below. In FIG. 1, the transfer head 10 moves above one of the parts feeders 4 and drives a motor 23 there to cause the case 12 to move up and down, thereby vacuumizing the electronic component P at the lower end of the nozzle 14a. Adsorb and pick up. Here, as shown in FIG. 2, it is assumed that the nozzle 14a projects downward and is in use, and the other three nozzles 14b to 14d retreat upward and are not in use.

When the electronic component P is picked up, the transfer head 10 moves above the substrate 2 and the nozzle 1 moves there.
The electronic component P is mounted at a predetermined coordinate position on the substrate 2 by the vertical movement of the 4a again. By repeating the above operation, the electronic components P are mounted on the board 2 one after another.
When the mounting of the electronic component P is completed, the substrate 2 is sent to the next step along the guide rail 3.

Next, regarding various inspections by the camera 13,
This will be described with reference to FIGS. 5 and 6. The camera 13 appropriately obtains image data in the vicinity of the lower end portion of the nozzle 14a in a used state protruding downward. 5 (a), (b),
(C) shows that immediately after the nozzle 14a moves up and down above the parts feeder 4 to pick up the electronic component P,
The perspective image acquired with the camera 13 is shown. Each of these perspective images is an image observed from obliquely above the nozzle 14a, and is a three-dimensional stereoscopic image as illustrated.

First, in FIG. 5 (a), the electronic component P is vacuum-sucked in a correct posture, and thus is normally picked up. In FIG. 5B, since the side surface of the chip P is vacuum-sucked, the chip P is erected and therefore a pickup error occurs. Further, in FIG. 5C, the nozzle 14a does not vacuum-adsorb the electronic component P, which is a pickup error. Therefore, in the case of FIGS. 5B and 5C, the operation of mounting the electronic component P on the substrate 2 is stopped,
Further, in the case of FIG. 5B, the electronic component P is discarded at the discard stage (not shown).

In the case of FIG. 5A, since the electronic component P has been correctly picked up, the transfer head 10 moves toward the substrate 2 to be mounted on the substrate 2. P may fall from the lower end of the nozzle 14a. Therefore, before the transfer head 10 reaches above the substrate 2 and mounts the electronic component P on the substrate 2, the vicinity of the lower end portion of the nozzle 14a is observed again by the camera 13 so that the nozzle 14a holds the electronic component P. Inspect whether there is. Then, when the same image data as that shown in FIG. 5A is obtained, the nozzle 14a is caused to perform an up-and-down operation and an operation of mounting the electronic component P on the substrate 2 is executed. FIG. 5 (c)
If similar image data is obtained, it is determined that there is a transfer error because the electronic component P has dropped during transfer,
The execution of the mounting operation is stopped.

Next, the inspection of the mounting error will be described with reference to FIG. FIG. 6 shows an image immediately after the electronic component P is mounted on the substrate 2. In FIG. 6A, the electronic component P is normally mounted on the substrate 2. In FIG. 6B, the electronic component P is mounted sideways, which is a mounting error. FIG.
In (c), there is no electronic component P on the substrate 2 and there is a mounting error. It should be noted that this mounting error is caused when the nozzle 14a is still holding the electronic component P without releasing the vacuum suction state of the electronic component P or when the pickup error shown in FIG. It occurs when the inspection of the transfer error is not performed. In the above operation,
When observing the vicinity of the lower end of the nozzle 14a with the camera 13, the light source 25 is turned on.

As described above, the transfer head 10 can detect various work mistakes. Moreover,
Since the vicinity of the lower end of the nozzle 14a is observed obliquely from above with the camera 13, three-dimensional image data can be obtained.
Based on the dimensional image data, it is possible to accurately determine the presence or absence of various work errors as shown in FIGS.

Furthermore, according to this transfer head 10,
You can also check for nozzle selection errors. That is, the transfer head 10 has a plurality of nozzles 14a to 14d, and the nozzles 14a to 14d are selected according to the type of the electronic component P. Then, only the selected nozzle protrudes downward, and the non-selected nozzle retreats upward. This nozzle selection is performed while the transfer head 10 moves above the parts feeder 4 including the electronic parts P to be picked up next.

The shape dimensions of the nozzles 14a to 14d are different from each other. Therefore, immediately after the nozzle selecting operation (this selecting operation is well known, the description thereof is omitted), the vicinity of the lower end portion of the nozzle is measured by the camera 13. And obtain the image data. This image data is the same as that shown in FIG. Then, this image data is analyzed by a well-known image processing technique such as a pattern matching method to determine the nozzle type and inspect whether the correct nozzle is selected. Of course, even when a plurality of nozzles are erroneously projected downward, this can be detected.

Next, another method of using the camera 13 will be described. 7 and 8 are explanatory views of a method for inspecting the moving distance of the transfer head of the electronic component mounting apparatus according to the embodiment of the present invention. FIG. 7 is a perspective view of the vicinity of the substrate, and FIG. FIG. In FIG. 7, a plurality of reference points A, B, C and D are formed on the upper surface of the guide rail 3. In this example, the reference points A to D are formed on the upper surface of the guide rail 3, but the reference points A to D may be formed on an element other than the guide rail 3.

Now, the transfer head 10 has a control unit (not shown).
By driving the X table 7 and the Y table 6 based on the command value issued from the above, the transfer head 10 moves a predetermined distance in the X direction and the Y direction. Not necessarily. Therefore, the transfer head 1
It is necessary to properly inspect whether 0 moves according to the command value. This inspection is performed as follows.

The current position of the camera 13 is known. Therefore, the control unit issues a command to move to the reference point A, for example. As a result, the X table 7 and the Y table 6 are driven by the command, and the camera 13 is moved right above the reference point A, where the camera 13 observes the reference point A. FIG. 8 shows an image obtained by this camera 13. In this example, the reference point A is Δx in the X direction from the optical axis O of the camera 13,
The position is shifted by Δy in the Y direction. From this, it is found that the transfer head 10 does not move according to the command value, and the moving distance includes an error in the X direction and the Y direction.

Therefore, when the electronic parts P of the parts feeder 4 are transferred to the substrate 2 as described above, the transfer head 10
It suffices to add a correction to the command value of the moving distance. This correction may be performed by proportionally distributing the positional deviations Δx and Δy according to the distance. As described above, according to the transfer head 10, the camera 13 can be used for various purposes.

The present invention is not limited to the above-described embodiment. For example, as an electronic component mounting apparatus, the transfer head is moved in a circle to move the transfer head as shown in Japanese Patent Laid-Open No. 2-99000. It can also be applied to a rotary type in which electronic components are transferred and mounted on a substrate.

[0034]

According to the present invention, a three-dimensional perspective image is obtained by observing the vicinity of the lower end of the nozzle from an obliquely upper position with a camera at an appropriate timing, and various work errors are obtained based on the perspective image. The presence or absence of can be accurately determined.

[Brief description of drawings]

FIG. 1 is a perspective view of an electronic component mounting apparatus according to an embodiment of the present invention.

FIG. 2 is a sectional view of a transfer head of the electronic component mounting apparatus according to the embodiment of the present invention.

FIG. 3 is a simplified plan view of a transfer head of the electronic component mounting apparatus according to the embodiment of the present invention.

FIG. 4 is a block diagram of a control system of the electronic component mounting apparatus according to the embodiment of the present invention.

FIG. 5A is an image view of the vicinity of the lower end of the nozzle of the electronic component mounting apparatus according to the embodiment of the present invention. FIG. 5B is a view of the vicinity of the lower end of the nozzle of the electronic component mounting apparatus according to the embodiment of the present invention. Image diagram (c) Image diagram of the vicinity of the lower end of the nozzle of the electronic component mounting apparatus according to the embodiment of the present invention

FIG. 6A is an image view of a vicinity of a lower end portion of a nozzle of an electronic component mounting apparatus according to an embodiment of the present invention. FIG. 6B is a vicinity of a lower end portion of a nozzle of an electronic component mounting apparatus according to an embodiment of the present invention. Image diagram (c) Image diagram of the vicinity of the lower end of the nozzle of the electronic component mounting apparatus according to the embodiment of the present invention

FIG. 7 is an explanatory diagram of a method for inspecting the moving distance of the transfer head of the electronic component mounting apparatus according to the embodiment of the present invention.

FIG. 8 is an explanatory diagram of a method for inspecting the moving distance of the transfer head of the electronic component mounting apparatus according to the embodiment of the present invention.

[Explanation of symbols]

 2 board 3 guide rail (positioning part of board) 4 parts feeder 10 transfer head 13 camera 14a, 14b, 14c, 14d nozzle 21 nut 21 feed screw 23 motor

Claims (2)

[Claims] 1. A parts feeder, a positioning part for a board,
An electronic component mounting apparatus comprising: a transfer head that vacuum-sucks and picks up an electronic component provided in a parts feeder at a lower end portion of a nozzle, and transfers and mounts the electronic component onto a substrate positioned by a positioning unit. The head has a camera and a plurality of nozzles arranged around the camera so as to be movable up and down. The lower end of the nozzle projecting downward is observed obliquely above the camera to obtain a perspective image. An electronic component mounting apparatus characterized in that. 2. An electronic component mounting method in which an electronic component provided in a parts feeder is vacuum-sucked and picked up by a lower end portion of a nozzle of a transfer head and transferred and mounted on a substrate positioned in a positioning unit. When the nozzle picks up the electronic component of the parts feeder, while transferring the picked-up electronic component to the substrate, when mounting the electronic component on the substrate, at least one timing after the mounting is completed, the transfer is performed. An electronic component mounting method comprising: observing a lower end portion of a nozzle and an electronic component from obliquely above by a camera provided in a head to obtain a perspective image, and inspecting for a work error based on the perspective image.