JPH1168266A - Printed board and marking system therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a marking system applicable to a high density printed board by printing a specified silk character or symbol directly onto an electronic device when a connecting conductor is arranged on a conductor pad and various electronic devices are soldered by surface mounting technology. SOLUTION: A silk 15 is set on a printed board 14 and a new silk character 11 is provided on an electronic device 13 being mounted on the electronic device mounting conductor 12 of a printed board 14. Since the silk character 11 is provided or formed directly on the electronic device 13, the area for forming the silk character around the silk 15 can be saved. Consequently, the inspection quality (visibility) is prevented from deteriorating due to approach or overlap of the silk character resulting in a printed board having high electronic device mounting density.

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 used for electronic equipment and the like and a marking method for such a printed circuit board.

[0002]

2. Description of the Related Art Most electronic equipment and electronic equipment are
An active device such as an IC and passive components such as a resistor and a capacitor are connected to a printed circuit board together with electric components such as a switch and a connector by soldering or the like. The use of printed circuit boards facilitates the design, assembly, and maintenance services of these devices. In these electronic devices and the like, it is common to use a plurality of independent or interconnected printed circuit boards.

[0003] These electronic devices and the like are becoming smaller and more sophisticated, and more devices are arranged at high density on a printed circuit board having a small area, and are connected by soldering by a surface mounting (SMT) technique or the like. In addition, it is common for mass-producing equipment to arrange components and devices on a printed circuit board not only manually but also by using a robot. It is indispensable to correctly and quickly arrange electronic devices and components at predetermined positions on the printed circuit board and connect them by soldering in order to reduce the manufacturing cost and maintain competitiveness of equipment. In addition, it is essential to improve the maintenance serviceability that the electric circuit disposed on the printed circuit board can be easily traced (tracked) even on the printed circuit board after assembly.

For these purposes, for example, Japanese Patent Application Laid-Open No.
Japanese Patent No. 193 discloses that a silk character (that is, a character printed by a silk screen printing technique) is used for a component type (for example, I
C, transistors, diodes, resistors, capacitors, etc.) are multi-colored and coded to simplify the number of characters (to cope with high-density mounting), and to make it easy to identify and determine the type of parts, etc. A silk printing technique for printed circuit boards is disclosed. The color coding of the silk characters printed on the printed circuit board is determined at the time of design, and the silk manuscript is also designed accordingly. At the time of printing, a printing operation is performed for each color.

Further, Japanese Utility Model Laid-Open No. 2-52468 discloses that
A printed wiring board is disclosed in which a color of a silk symbol or a silk character is color-coded for each component, for example, a resistor is white and a capacitor is orange, and an error such as insertion of the component is prevented.

FIGS. 3A to 3D show typical printed circuit board manufacturing processes according to these conventional examples. First, (a)
In the above method, a copper foil (layer) uniformly formed on the entire surface of the insulating plate is formed by using a well-known etching technique or the like.
1 and a connection circuit pattern 32 are formed. Next, in (b), a well-known resist 33 is applied to protect the conductor pattern and prevent a short circuit. Further, a silk 34 and a silk character 35 shown in FIG. Finally,
As shown in (d), the electronic component 36 is arranged between the conductor pads 31 and soldering is performed by a known surface mounting (or reflow soldering) technique. Thus, predetermined marking is performed on the printed circuit board, and the manufacturing process is completed. Although FIG. 3 shows only a part of the printed circuit board, it is a matter of course that many similar patterns and electronic components are formed over the entire surface of the printed circuit board.

[0007]

The conventional printed circuit board formed as described above has problems and problems as shown in FIG. That is, according to the conventional technique, in the case of high-density mounting, the mounting density of electronic components becomes high, so that the proximity of the silk characters 51 or the overlapping of the silk characters 5 on the printed circuit board is caused.
2 may occur and a silk reading error may occur during the inspection of the printed circuit board.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method of marking a printed circuit board that can handle a high-density printed circuit board.

[0009]

In order to solve the above-mentioned problems, a printed circuit board according to the present invention has a conductor pad and a connection pattern disposed on the surface thereof. On a printed circuit board in which electronic components are connected by soldering by a surface mounting technique, silk characters such as predetermined characters or symbols are directly printed on the electronic components.

According to another aspect of the present invention, there is provided a marking method for a printed circuit board, which performs a predetermined marking required for various electronic components surface-mounted on the surface of the printed circuit board. An electronic component corresponding to the conductive pad formed on the surface of the electronic component is surface-mounted, and a predetermined silk character is printed and formed on the electronic component mounted on the surface.

Here, the marking is performed by a CAD system having position coordinates and height information of the electronic component.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a printed circuit board marking method according to the present invention will be described below in detail with reference to the accompanying drawings.

First, FIG. 1 is a plan view of a partial surface of a printed circuit board for explaining a preferred embodiment of a marking method for a printed circuit board according to the present invention. According to the present invention, the silk 15 is provided on the printed board 14. Next, the printed circuit board 14
A new silk character 11 (R02 in FIG. 1) on an electronic component 13 mounted on the electronic component mounting conductor (pad) 12 of FIG.
Is provided.

As described above, by providing or forming the silk character 11 directly on the electronic component 13, the area for the silk character provided around the silk 15 described above with reference to FIG. Becomes possible. Therefore, the problem of deterioration in inspection quality (visibility) due to the approach or overlap of the silk characters can be solved, and a printed circuit board with a high mounting density of electronic components can be obtained.

Next, a manufacturing process of a printed circuit board using the present invention will be described with reference to FIG. During the layout CAD library creation step 203, in addition to the conventional information constituting the library, information on the silk on the part and the height of the part is input. The layout CAD using the component shape library 204 including these pieces of information and the netlist 202 output from the circuit design CAD 201 as input information.
Step 205 is executed. The layout designer specifies the layout coordinates of the electronic components used in the circuit and the mounting direction in the layout. The height of the electronic component and the initial state of the silk on the component are provided by the component shape library 204.

If it is desired to change the contents of the component shape library 204 during layout design by the layout CAD 205 or to describe information not in the component shape library 204 in the electronic component, the layout CAD is used.
205 registers the contents.

After the layout design by the layout CAD 205 is completed, as a result, printed circuit board design data 206 similar to the conventional one and component top surface silk data 207 for realizing the printed circuit board marking method of the present invention are output.

The component upper surface silk data 207 includes the contents of all silk characters and symbols printed on electronic components arranged and connected at predetermined positions on the printed circuit board, their output coordinates, and the rotation direction at the time of output. , Including height information of each electronic component to be printed.

Using the manufacturing data 206, a board manufacturing step 208 is executed by the same procedure as in the prior art, and a printed board 209 is manufactured. Next, the printed circuit board 209
, An electronic component mounting step 210 is performed. As a result, a printed board 211 on which electronic components are mounted is created.

The printed circuit board 211 on which the electronic components are mounted
In response to this, a silk printing process 212 is performed on the upper surface of the electronic component using the component upper surface silk data 207 output by the layout CAD 205. This completes the printed circuit board manufacturing process. In the component upper surface silk printing process 212, the printed circuit board 211 on which electronic components are mounted is
Is included in the component top surface silk data 207. Using the print characters, print coordinates, the rotation angle of the characters to be printed, and the height information of the components to be printed, the printing process of the silk on the components is performed.

The manufacturing process of a printed board according to the printed board marking method of the present invention described with reference to the flowchart of FIG. 2 will be described with reference to FIG. 4 which is a partial plan view of the printed board. A conductive pad 41 for mounting electronic components and a connection circuit pattern 42 are formed from a copper layer using a conventional etching technique.
Is formed (see FIG. 4A).

Next, in the step of FIG. 4B, protection of the conductor patterns 41 and 42 and short-circuit (short-circuit) in the soldering step
A solder resist 43 for prevention is applied. Subsequently, FIG.
In the process (c), the silk 44 for component mounting inspection is used.
Print. At this time, if there is a silk character to be printed on the printed board, it is printed together with the silk 44.

Next, in the step of FIG. 4D, the electronic component 45 is mounted at a predetermined position on the printed circuit board. Finally, FIG.
In the step (e), a silk character 46 (character R02 in this specific example) is printed on the mounted electronic component 45.

As is apparent from the above description, in the method of marking a printed circuit board according to the present invention, a required marking (silk character) is printed on a space near an electronic component mounted on the printed circuit board as in the related art. Instead, silk characters are printed on the electronic component mounting portion of the printed circuit board and / or on the electronic component to be mounted.

[0025]

As will be understood from the above description, according to the printed board marking method of the present invention, after various electronic components are mounted on the printed board, silk characters are printed on these electronic components. However, no matter how close they are arranged, there is no overlap and a highly visible printed circuit board with extremely high visibility can be obtained. In addition, silk characters are of high quality and easy to read. Further, there is a practically remarkable effect that various information such as a connector pin number and a symbol indicating a character type can be easily handled.

[Brief description of the drawings]

FIG. 1 is a plan view showing a part of a preferred embodiment of a marking method for a printed circuit board according to the present invention.

FIG. 2 is a flowchart illustrating a process of manufacturing a printed board according to the printed board marking method of the present invention.

FIG. 3 is a manufacturing process diagram of a conventional printed circuit board.

FIG. 4 is a view showing a manufacturing process of the printed circuit board according to the present invention according to FIG. 2;

FIG. 5 is a diagram illustrating a problem of the conventional printed circuit board of FIG. 3;

[Explanation of symbols]

 41 conductor pad 42 connection circuit pattern 45 electronic component 46 silk character

Claims (3)

[Claims] 1. A printed circuit board having a conductor pad and a connection pattern disposed on a surface thereof, wherein a connection conductor is disposed on the conductor pad and various electronic components are soldered and connected by a surface mounting technique. A printed circuit board on which silk characters such as predetermined characters or symbols are directly formed by printing. 2. A marking method for a printed circuit board for performing a predetermined marking required for various electronic components surface-mounted on the surface of a printed circuit board, wherein the electronic component corresponding to the conductive pad formed on the surface of the printed circuit board is provided. A marking method for a printed circuit board, which is surface-mounted and a predetermined silk character is printed and formed on the surface-mounted electronic component. 3. The method according to claim 2, wherein the marking is performed by a CAD system having position coordinates and height information of the electronic component.