JP2002043735A - Printed circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a partitioning line which clearly partitions a land group for chip parts into each other's lands so that a solder bridge or the like can be easily found by a visual inspection when the solder bridge or the like is caused on the partitioning line. SOLUTION: Conductor patterns are formed by printing on a substrate, where some conductor patterns are used for mounting a large part such as electronic part, and others, which is formed as a land group 10 for chip parts, are used for mounting small parts such as capacitors. Broad partitioning lines 15, 16,... are formed between each other's lands of 11, 12,... by silk-screen printing for the land group 10 for chip parts so that the solder bridge or the like can be easily found by the visual inspection when the solder bridge or the like is caused on the board partitioning lines 15, 16,... in a soldering process.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed circuit board on which a large number of electronic components are mounted, and in particular, when arranging chip components side by side at small intervals, even if the lands that are in close contact are connected by solder (so-called solder). Solder bridge), and a printed circuit board configured so that it can be easily inspected visually.

[0002]

2. Description of the Related Art In a printed circuit board provided by printing circuit wiring on an insulating substrate, electronic parts such as ICs and chip parts such as resistors and capacitors are provided at designated positions of the circuit of the conductor pattern. Is specified to be implemented.
In the conductor pattern, in addition to the pattern for mounting the electronic components, lands for arranging and mounting small chip components are arranged at very narrow intervals, and the land for the chip components is provided with very small chip components. And implemented. Then, after mounting electronic components and chip components on designated portions on the board, respectively, soldering is performed through a soldering bath, and the printed circuit board is checked with a checker to determine whether there is a soldering defective portion. Inspection.

[0003]

However, in the inspection of a printed circuit board on which small components are mounted on the board, the soldering state of all components cannot be detected by a checker, and a part of the inspection is performed by a visual inspection. It is necessary to detect defective soldering points. In particular, in a place where the chip components are provided in close contact with each other, there is a problem that the leads of the adjacently arranged chip components are short-circuited by solder. However, there is a disadvantage that the small chip components cannot be easily identified by a visual inspection at a place where they are mounted in close contact with each other.

It is an object of the present invention to provide a means for easily confirming the occurrence of a solder bridge or the like when a small chip component is placed on the substrate and mounted by soldering. .

[0005]

According to the present invention, there is provided a printed circuit for forming a conductor pattern on an insulating substrate, covering the conductor pattern with a solder resist except for a land, and soldering a lead of an electronic component on the land. Regarding the substrate. The present invention is characterized in that sections of the insulating paint are formed by silk-printing between lands between the chip components at locations where the chip components are mounted side by side on the insulating substrate.

As described above, since partitions are formed by printing paint between lands where a number of chip components are arranged and mounted, it is possible to easily visually confirm that a solder bridge has occurred. . Further, since the sections are formed by silk printing, the sections can be easily formed even between lands that are closely arranged.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The substrate of the present invention will be described with reference to the illustrated example. The example shown in FIG. 1 shows a configuration of a part of a general printed circuit board. The printed circuit board 1 is provided with a portion for arranging electronic components 5 and 7 at arbitrary positions on the printed circuit board 1, and a circuit such as an IC is provided. The position to mount the part is specified.
The printed circuit board 1 is, like a conventional printed circuit board,
A conductor pattern is formed on the surface of an insulating plate member 2 made of an insulator made of glass-epoxy resin, paper-phenol, ceramics, or the like. Then, the surface of the insulating substrate is covered with an insulating layer, and a process is performed to expose only terminal portions (lands) to be soldered. Also,
On the surface of the substrate are provided, by silk printing, characters describing component names, marks for designating mounting positions of electronic components, and the like. Lands 6 and 8 are formed on the insulating substrate 2 at positions where the electronic components 5 and 7 are mounted, corresponding to the leads of the electronic components 5 and 7. Further, the electronic components 5, 7
Together with the parts to be mounted,
Are arranged to form a large number of sections in which chip capacitors and other small parts can be mounted side by side.

When mounting a component on the electronic component mounting designation portion of the insulating plate member 2, the electronic components 5 and 7 are positioned according to the directions described on the marks, and a bond (registered trademark) or the like is used. The electronic components are fixedly arranged by using.
By fixing the electronic components, a large number of leads protruding from each of the electronic components are connected to the lands 6.
And 8... Are positioned. As described above, the components such as the electronic components are positioned with respect to the electronic component mounting portion, and the mounting portion of the chip component to be arranged in the chip component land group 10 includes the designated capacitor, resistor, and other small components. Install each part. After mounting electronic components and small chip components according to the conductor pattern formed on the insulating plate member 2,
Through the flow soldering bath, soldering of each terminal part is performed, and the lead of each electronic component and chip component is
Solder to the specified land.

The land parts 11, 12,... For chip parts arranged in the chip part land group 10 are for mounting very small parts, and the mounted chip parts are arranged in a very close contact state. There is a problem that only small gaps can be provided. Therefore, in the present embodiment, as shown in FIG. 2, when performing silk printing, the land portion 1 is formed by using an insulating ink such as white.
Partition lines 15, 16,... Between each of 1, 12,.
Are simultaneously formed. The partition lines 15, 16,...
.. May be formed longer than the lengths of the lands 11, 12,..., And the lands 11, 12,.

As described above, the chip component land group 1
By dividing the land portions 11, 12,... By a white line for a large number of chip components designated as 0, for example, the chip components were mounted on each land portion and soldered. Sometimes, the partition line 15 disposed between the two land portions 11 and 12 makes it easy to visually confirm even if a solder bridge occurs. The partition line 15 also has an effect of suppressing the occurrence of the solder bridge itself.

In the chip component land group 10, the partitioning lines 15 partitioning between the land portions are separated from the solder layer by using another screen after the processing for forming the solder layer. Partition line 1 using another insulating paint
When 5 or the like is written, the partition line can be formed as a line having an arbitrary width and thickness. It is to be noted that the partition lines 15 can be made of any color ink other than white as long as the color can identify the solder bridges. May be formed wider. It would be better if the solder bridge could be visually determined to form the solder bridge so as to cross over the partition line, and if it could be processed so that the solder would not be placed so as to cross the partition line. The effect can be achieved.

A chip component is mounted on the chip component land group and soldered through a flow solder bath. The soldered state of the chip component is mounted as shown in FIG. As shown in FIG. 3, the chip components 20...
2 are positioned and attached to each other, and are connected to respective corresponding lands by soldering portions 21. As described above, even when the solder bridge A is formed so as to straddle the partition lines 15 when the chip components are soldered, the solder bridges are different in color from the partition lines 15. Can be easily determined visually.

[0013]

Since the printed circuit board of the present invention is constructed as described above, the insulating paint is formed by printing between the lands where a number of chip components are arranged and mounted, so that the printed circuit boards are closely arranged. When a solder bridge is formed between lands, it can be easily determined. In addition, since the silk printing means is used to form the partition by the printing, it is possible to easily form the partition line, and to determine whether a solder bridge has occurred in a narrow gap between chip components. Can be easily provided.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating a configuration of a printed circuit board.

FIG. 2 is an enlarged explanatory view of a chip component land group.

FIG. 3 is an explanatory view of a state where a chip component is mounted.

[Explanation of symbols]

1 printed circuit board, 2 insulating plate member, 5.7
Electronic components, 6.8 lands, 10 Chip component lands, 11/12 lands, 15.16
Partition line, 20 chip parts, 21 soldering part.

Claims (1)

[Claims] 1. A printed circuit board for forming a conductor pattern on an insulating substrate, coating the conductor pattern with a solder resist except for a land, and soldering leads of electronic components on the land. A printed circuit board, wherein a section of an insulating paint is formed by silk-printing between lands between the chip components at a portion where the chip components are mounted side by side.