JPH02214577A - Adhesive application method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an adhesive application method, and particularly to an adhesive for fixing electronic components until they are soldered when mounting electronic components on a circuit board. The present invention relates to an adhesive application method that can be suitably applied to the application of adhesives.

2. Description of the Related Art Conventionally, when mounting electronic components on a circuit board, as shown in FIG. 13
are fixed, and then the electrodes or leads 14 of the electronic component 13 and the electrodes 15 of the circuit board 11 are joined. A common method for joining them is to apply cream solder on the electrodes 15 of the circuit board 11 in advance, and after mounting the electronic components 13, reflow the cream solder to perform solder joining.

The application of the adhesive 12 to the circuit board 11 is carried out using a device that can accommodate the adhesive 23 inside and has a discharge port 24 at the lower end so that pressurized air can be supplied to the upper space, as shown in FIG. This is done using a well-known dispenser 22 configured. That is, the circuit board 11 and the dispenser 22 are
, after relatively moving in the Y direction to position the dispenser 22 opposite the center of the electronic component mounting position of the circuit board 11, the dispenser 22 is lowered from the solid line position to the position shown by the imaginary line, and pressurized air is supplied for a predetermined time. and then apply a predetermined amount of adhesive 2
3 to adhere the adhesive 23 to the circuit board 11, and then raise the dispenser 22 and cut the adhesive 23, thereby forming the adhesive 12 coated on the circuit board 11 as shown in the figure. ing. Moreover, by controlling the discharge pressure and discharge time of the pressurized air by the discharge control unit 21, an appropriate application state can be obtained.

Problems to be Solved by the Invention However, even if the discharge control unit 21 is adjusted in advance so as to obtain a proper application state, environmental changes or adhesive loss may occur during continuous automatic application. The coating condition may change due to variations in characteristics or changes in characteristics, resulting in an inappropriate coating condition, and when electronic components are subsequently mounted, the electronic components may not be securely fixed or the adhesive may protrude significantly. There is a problem in that it may have an adverse effect on the subsequent bonding process. Moreover, such adhesive application defects are difficult to detect until problems occur in subsequent processes, and during that time, all circuit boards with electronic components attached become defective. . In particular, in recent years, as electronic components have become increasingly smaller, the range that is recognized as an appropriate coating state has become narrower, and it has become important to solve this problem.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, it is an object of the present invention to provide an adhesive application method that can immediately detect when the adhesive application state becomes poor and can automatically adjust the application state to a proper application state.

Means for Solving the Problems In order to achieve the above object, the present invention dispenses adhesive from a dispenser, applies the adhesive to a predetermined position on a substrate, and measures the state of application of the adhesive with a camera immediately after application. However, it is characterized in that a failure is displayed when the result is outside a set acceptance range.

Moreover, the second aspect of the present invention is to automatically change the discharge time or discharge pressure of the adhesive from the dispenser when the adhesive is out of the acceptable range.

Further, in the third aspect of the present invention, a red adhesive is used and a camera capable of color discrimination is used.

According to the present invention, each time adhesive is applied with a dispenser, the application state is measured with a camera, and if there is a defect, it is displayed, so that application defects can be detected immediately and the occurrence of defective products can be minimized. can be stopped.

Further, according to the second aspect of the invention, since the coating is automatically adjusted to a proper coating state, the coating can be efficiently coated on the substrate.

Furthermore, according to the third invention, since only the shape of the adhesive can be detected during measurement with a camera, image processing can be performed in a short time using a simple processing circuit, and even if the number of measurement steps is increased during application, speeding up is possible.

EXAMPLE Hereinafter, an example of the present invention will be described based on FIGS. 1 and 2.

In FIG. 1, 1 is a circuit board on which electronic components such as ICs and chip-type electronic components are mounted, and is fixed on an X-Y table (not shown) that can be positioned in the X-Y direction. . Reference numeral 2 denotes a dispenser that is movably disposed at a predetermined position above the X-Y table, has a storage space for the adhesive 3 inside, and is configured to be able to discharge the adhesive 3 from a discharge port 4 at the lower end. has been done. The upper part of the housing space of the dispenser 2 is configured to be able to supply pressurized air, and a discharge control unit 5
It is configured so that it can be set arbitrarily.

Reference numeral 6 denotes a recognition camera such as a CCD camera that recognizes the shape of the adhesive 10 applied to the circuit board 1 by the dispenser 2, and is disposed on the side of the dispenser 2. The recognition camera 6 is capable of color discrimination, and the adhesive 3 is a red-colored adhesive. 7
is an image processing circuit that processes the image signal output from the recognition camera 6 and outputs a signal regarding the shape of the applied adhesive 10, and the output signal is input to the CPU 8. Control unit 5 is controlled.

Next, the operation of applying adhesive to the circuit board 1 will be explained with reference to FIG.

First, the circuit board 1 was set on the X-Y table using a supply means (not shown) (Step #1), and then the X-Y table was moved to position the adhesive to be applied directly below the dispenser 2. After that (step #2), the dispenser 2 is lowered to the position shown by the imaginary line in FIG. 1 (step #3), and the adhesive 3 is discharged from the discharge port 4 (step #4). The discharge pressure and discharge time at this time are determined according to preset conditions so that the shape (planar shape, size, height, presence or absence of protrusions, etc.) of the applied adhesive 10 is appropriate. It is controlled by a control unit 5. Next, the dispenser 2 is raised (step #5), the adhesive is cut at the discharge port 4 position, and the adhesive 10 is applied onto the circuit board l. When the dispenser 2 rises, the recognition camera 6 immediately recognizes the shape of the adhesive lO, the image processing circuit 7 measures the shape, and the data is transferred to the CPU 8 (
Step #6). At this time, if the adhesive 3.10 is made red so that it can be clearly distinguished from the color of the circuit board 1 and other parts, and if the recognition camera 6 is made to be able to distinguish colors, only the adhesive 10 can be removed. The shape can be measured, and the measurement can be performed in a short time with a simple circuit configuration. In CPU8, transferred adhesive 10
The shape data is compared with a preset appropriate range of the adhesive 10 to determine pass/fail (step #7).

After proceeding to the pass judgment (step #8), it is then judged whether all the adhesives have been applied to the circuit board 1 (step #9). If not, the process returns to step #2 and repeats the above operation. , the adhesive is sequentially applied to the adhesive application portions of the circuit board 1. If all the circuit boards 1 have been coated, the circuit board 1 is ejected and replaced with the next circuit board 1 (step #10), and then it is determined whether the circuit board 1 is set in the predetermined position. 11) If set, return to step #2 and repeat the above operation; if not set, stop the machine and end step #13).

As a result of the determination in step #7, if it is determined that adhesive application cannot be continued (step #12), such as because the adhesive 10 has not been applied at all, the process advances to step #13 and the machine is stopped. and exit.

If the result of the determination in step #7 is that the shape of the adhesive is not appropriate and it is necessary to change the discharge conditions such as the discharge pressure or discharge time (step #14), a defect signal is output. At the same time, a red adhesive 3 is applied to form a defective mark on an appropriate location on the circuit board 1, and an indication that the circuit board 1 is defective is also made.
Step #15), then the bad signal is repeated N times (for example, 2
~5 times) Step # to determine whether or not it has been output continuously
16) If the output is continuous, the process moves to step #13, the machine is stopped, and the process ends.

On the other hand, if the defective signal is not output continuously, the ejection conditions are changed based on the preset program depending on the degree of inadequacy (step #17), and then the circuit board 1 is replaced in the same manner as above. (step #18), and also determines whether the circuit board l has been set (step #18).
19) If it has been set, the process returns to step #2 and repeats the above operation; if it has not been set, the process proceeds to step #13 and thereafter, stopping the machine and ending the process.

As a result of the determination in step #7, if the adhesive 10 is under-applied and it is determined that re-applying is possible (step #20), the discharge conditions for re-applying are set, and the To change the dispensing conditions (step #21), return to step #3 and reapply adhesive to the same location.
Thereafter, the above operation is repeated.

In this way, the adhesive 10 is automatically and sequentially applied to the circuit board 1, and if the adhesive 10 is not applied properly, this is immediately detected, a defective signal is output, and the circuit board 1 is
It is possible to form a defective mark on the adhesive 3 and adjust the conditions for discharging the adhesive 3 from the dispenser 2 so as to automatically obtain a proper application state.

Effects of the Invention According to the adhesive application method of the present invention, each time adhesive is applied with a dispenser, the application state is measured with a camera, and if there is a defect, it is displayed, so that a coating defect can be immediately detected. This has the effect of minimizing the occurrence of defective products.

Further, according to the second aspect of the invention, the conditions for discharging from the dispenser are automatically adjusted so as to achieve a proper coating state, so that proper coating on the substrate can be efficiently performed.

Furthermore, according to the third invention, since only the shape of the adhesive can be detected during measurement with a camera, image processing can be performed in a short time using a simple processing circuit, and even if the measurement process increases during application, speeding up is possible. be effective.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an embodiment of a coating apparatus for carrying out the adhesive coating method of the present invention, FIG. 2 is a control flowchart of coating operation, FIGS. 3 and 4 show a conventional example, and FIG. 3
The figure is an explanatory diagram showing the process of mounting electronic components onto a circuit board, and FIG. 4 is a schematic diagram of the coating apparatus. l... Circuit board, 2... Dispenser, 3... Adhesive, 5... Discharge control unit, 6... Recognition camera, 7... Image processing circuit, 8... CPU, 10... Applied adhesive. Representative/4 patent attorneys: Shigetaka Awano, 1 person Figure 4

Claims (3)

[Claims] (1) Dispense adhesive from a dispenser and apply the adhesive to a predetermined position on the board, measure the adhesive application status with a camera immediately after application, and display a failure when it is outside the set acceptable range. An adhesive application method characterized by: (2) The adhesive application method according to claim 1, wherein the adhesive discharging time or the discharging pressure from the dispenser is automatically changed when the adhesive is out of the acceptable range. (3) The adhesive coating method according to claim 1 or 2, characterized in that a red adhesive is used and a camera capable of color discrimination is used.