JPH01278795A - Masking method for printed board and masking type - Google Patents

Abstract

PURPOSE:To enable the masking with a single sticking operation easily by a method wherein a masking seal whose shape is similar to that of the arrangement of lead pins of an after mounting component is used to mask pin holes of the after mounting component together. CONSTITUTION:A masking seal 18, whose shape is equal to that of the arrangement of lead pins 14 of a component 12 inserted into pin holes 16 which are to be masked, is previously formed by frame-cutting a masking tape. The pin holes 16, into which the pins 14 of the component 12 are to be inserted, are covered with a single masking seal 18. Therefore, an operator separates the masking seal 18 from the masking tape and sticks it on a masked part. By these processes, parts required to be masked can be masked with a piece of masking seal without cutting a mask tape into pieces for each hole and sticking them, so that holes scattering in a wide range can be easily masked.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for masking a printed circuit board and a masking tape, and particularly to a method for masking a printed circuit board, and particularly for immersing the masking tape in a solder bath in order to solder lead pins of components mounted on a printed circuit board. The postscript relates to a method for masking pin holes for parts and improvements to the masking tape used therefor.

[Conventional technology]

Conventionally, when components are mounted on a printed circuit board and the component lead pins are soldered, the protruding surfaces of the pins of the printed circuit board are immersed in solder 4fI and soldered all at once. At this time, use flyback transformers that are difficult to clean after soldering, transformers that tend to lose their balance when immersed in the temporary solder bath, etc.fffffl.
After the soldering process, parts such as parts are mounted separately and soldered. In this type of retrofitting, pin holes for components are drilled in the printed circuit board from the beginning, but these pin holes must be masked in advance to prevent them from being blocked when immersed in the solder bath. There is.

Conventional retrofitting methods for masking pin holes in parts include:
A method is to insert a pin made of a material that does not adhere to solder, such as stainless steel, into the pin hole, or as shown in Figure 3, use a heat-resistant masking tape with a width of at most several 10 Il 111 to attach it to the pin hole. There are known methods to do this.

[Invention tries to solve! ! I topic]

However, the above conventional method has the following problems. That is, when stainless steel pins are used, there is a problem in that the work of inserting a large number of stainless steel pins into individual pin holes is complicated, and a lot of time is taken up in the incidental work of masking. In this case, it may be possible to mask the pin holes for one component all at once using a plate with as many stainless steel pins as the number of pins in the component (the pin positions may differ even for the same type of component). ,
There is an inconvenience that plates with pins must be prepared as many as there are various types of parts. In addition, the latter method of using masking tape is effective when the pin holes are arranged in a straight line, but in reality the pin holes are not arranged in a straight line, and as shown in Figure 3, the pin holes are arranged in a straight line. Even in the case of pin holes l for component glue-do pins, they are often arranged in a circular or polygonal shape, and in such cases, tape pieces 2 cut into several pieces of masking tape are used to partially cover one row of pin holes. This requires pasting the mask onto the printed circuit board 3 in several steps, which again poses the problem of taking time for masking.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, it is an object of the present invention to provide a method for masking a printed circuit board and a masking tape that allows masking to be performed simply by applying the mask once.

[Means to solve the problem]

In order to achieve the above object, a method for masking a printed circuit board according to the present invention is a method for masking pin holes of components for retrofitting when immersing a component mounted on a printed circuit board in a solder bath for soldering. The masking was retrofitted using a masking seal having a shape similar to the arrangement shape of the pins to which the parts were glued, so that the pin holes of the parts could be masked all at once. In addition, the masking tape according to the present invention is a masking tape that prevents solder from adhering to pin holes for mounting components on a printed circuit board, and is formed in a shape similar to the arrangement shape of lead pins of a component to be mounted in the pin holes to be masked. The design consists of a masking sticker with a frame cut out.

[Effect]

In the above configuration, a masking seal that has the same arrangement shape as the lead pins of the component to be installed in the pin hole to be masked is pre-formed on the masking tape, so the pins of the component can be inserted. The pin hole will be covered with one masking seal.

Therefore, the operator only has to peel off the masking sticker from the masking tape and apply it to the masking area.As a result, the necessary masking area can be masked with a single masking sticker, and pin holes over a wide area can also be covered with the masking tape. Masking can be done easily without having to cant and cut and paste.

〔Example〕

Hereinafter, specific embodiments of the printed circuit board masking method and masking tape according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is an explanatory diagram of a method of masking a printed circuit board according to an embodiment, and the printed circuit board 10 has a plurality of pin holes 16 into which lead pins 14 of a flyback transformer 12, which is a component that is retrofitted, are inserted into the flyback transformer 12. The holes are arranged in a similar shape to the outer shape of the transformer 12. It is necessary to mask the solder welding surface 10A of the board 10 so that the pin holes 16 for the flyback transformer 12 are not blocked by solder when immersed in a solder bath to solder other mounted components. There is. The pin holes 16 of the flyback transformer 12 are arranged on a circumferential line with a larger diameter than those of other mounted components, so in the embodiment, a masking seal 18 that can mask 16 rows of pin holes at once is used. In other words, a masking sticker 18 cut out in a circular shape corresponding to the arrangement shape of the lead pins 14 of the flyback transformer 12 is prepared in advance, and this is pasted to the protection area 20 of the 16 rows of pin holes and hung. This is to prevent the pin holes 16 from clogging.

FIG. 2 is a perspective view of masking tape 22, which is the material of masking seal 1B. This masking tape 22
is heat-resistant paper coated with a silicone acrylic heat-resistant resin adhesive, and the retrofit is approximately 6mm thick, covering the maximum width of the part.
It is considered to be a long tape with a tape width of about 0M. The masking tape 22 has masking stickers 18 arranged adjacently in a circular shape corresponding to the outer shape of the flyback transformer 12 and cut out in advance along its longitudinal direction. The masking sticker 18 is made into a tape, unwound as necessary, and the masking sticker 18 is taken out to be attached to the printed circuit board 0.

According to the printed circuit board masking method and masking tape according to the embodiment configured as described above, the pin hole 1G for the lead pin of the flyback transformer 12, which is a component that is retrofitted, has an external shape of the flyback transformer 12. This means that masking can be performed all at once using a similar masking seal I8. Therefore, the time required for masking work, which is a pre-processing process for soldering, is greatly reduced, and work efficiency can be improved. In particular, when cutting and pasting the masking tape 22, unnecessary parts were often masked, but in this example, the minimum necessary area can be accurately masked, so it can be efficiently used even when the packaging density is high. Can perform masking work.

In the above embodiment, the masking seal 18 is circular to match the shape of the flyback transformer 12, but it may also be polygonal, and the masking seal 18 may be retrofitted with a shape similar to the arrangement of the lead pins 14 of the component. Alternatively, a peeling knob 24 may be integrally provided on the masking seal 18 in order to simplify the peeling operation in a subsequent process.

〔Effect of the invention〕

As explained above, according to the present invention, since the masking tape is retrofitted using a masking sticker similar to the part glue-dopin arrangement shape according to the area to be masked, even if a wide area is to be masked, It is possible to protect pin holes from solder by simply applying it once, and the effect of improving masking work efficiency can be obtained.

[Brief explanation of the drawing]

Fig. 1 is an explanatory perspective view of a method for masking a printed circuit board according to an embodiment, Fig. 2 is a perspective view of a masking tape with a masking seal cut out, and Fig. 3 is a perspective view of a masking method using a conventional masking tape. It is. 10...Print 2H anti, 12...Flights matsu transformer (retrofitted parts), 14...
・Pin, I6...Pin hole, 18...Masking sticker, 22...Masking tape.

Claims (2)

[Claims] (1) In a method of masking pin holes of a retrofitted component when immersing the mounted product on a printed circuit board in a solder bath for soldering, the masking has a shape similar to the arrangement shape of lead pins of the retrofitted component. A method for masking a printed circuit board, characterized in that pin holes of the retrofitted parts are collectively masked using a seal. (2) In masking tape that prevents solder from adhering to pin holes for mounting components on printed circuit boards, a masking sticker formed in a shape similar to the arrangement shape of the lead pins of the component to be mounted in the pin holes to be masked is used as a frame. Masking tape that is characterized by being removable.