JP3170879B2 - Push-back type printed wiring board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a push-back type printed wiring board which is a kind of printed wiring board for mounting electronic parts.

[0002]

2. Description of the Related Art In a printed wiring board comprising a main board and a discarded board arranged around the main board, the board is separated from the discarded board by a press before mounting components, and then the discarded board is re-mounted. A push-back type printed wiring board is called a push-back type printed wiring board, and has a feature that the discarded board can be easily removed after component mounting and soldering are completed.

FIG. 2 is a plan view showing the structure of a conventional push-back type printed wiring board. In FIG. 2, reference numeral 20 denotes a printed wiring board, and a main board 21 on which electronic components are mounted.
And an inner discard plate 23 and an outer discard plate 22. When the main substrate 21 is punched out by a die by a pushback method, the main substrate 21 having a circular outer shape is once removed and then returned, so that an angular displacement occurs in the main substrate 21 in the circumferential direction. Reference numeral 24 denotes a recognition mark arranged on the outer discard plate 22. Reference numeral 25 denotes lands of chip components (integrated circuits, super-integrated circuits, etc.) arranged on the main board 21.

Next, the operation will be described. In the electronic component reflow soldering step, the openings of the metal mask for applying cream solder and the electronic component lands 25 arranged inside the main board 21 are aligned, and the cream solder is accurately applied to the chip component lands 25. Next, the chip component is mounted on the applied cream solder. At this time, the center value of the chip component land is accurately read by the recognition mark 24 provided on the outer discard plate 22, and the chip component is automatically mounted. It is mounted on the main board 21. Then, the chip component was fixed in a high-temperature electric furnace.

[0005]

However, in the above-mentioned conventional push-back type printed wiring board, since the main board 21 is circular, inclination in the circumferential direction occurs. It is difficult to accurately match the metal mask and the chip component land, and there has been a problem in that when the cream solder is applied, the chip component land 25 is shifted.

The push-back type printed wiring board of the present invention solves such a conventional problem, and is an excellent push-back type printed circuit in which a reflow soldering process of a chip component can be accurately performed using a recognition mark. It is an object to provide a wiring board.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a pushback type printed wiring board comprising a main board and a discarded board arranged around the main board to detect a board position. Is provided on the present substrate.

[0008]

With this configuration, by disposing the recognition mark on the main board, it is possible to detect the displacement of the main board when the metal mask and the chip component land are aligned.
It is possible to detect a defect in the printed wiring board before applying the cream solder. Further, since the displacement of the present substrate can be detected, the center value of the land of the chip component can be detected, and accurate automatic mounting of the chip component can be performed.

[0009]

FIG. 1 is a plan view showing the structure of an embodiment of the present invention. In FIG. 1, reference numeral 10 denotes a push-back type printed wiring board. The main board 11 on which electronic components are mounted, the outer discard substrate 12 on which a series of guide holes are arranged in an electronic component mounting process, and the inner discard substrate 13 necessary for preventing solder and flux from rising during dip soldering Consists of When the outer shape of the main board 11 is a circular shape in the push-back type printed wiring board, the main board 11 is inclined in the circumferential direction with respect to the outer disposal board 12. On the other hand, in order to reduce the inclination even a little, a straight portion 16 is provided at one place with respect to the circle. Further, a cross mark 17 is formed with a double resist so that the inclination can be visually checked. Reference numeral 14 denotes a recognition mark provided on the substrate 11 used for positioning the metal mask and the printed wiring board and for positioning the printed wiring board when the chip components are automatically mounted. Also 18
Is a slit for preventing the printed wiring board from warping during pushback. According to the above configuration, the present substrate 1
1 and the electronic component lands 15 on the substrate 11 against the displacement in the circumferential direction due to the pushback of
By arranging the recognition mark 14 on the main substrate 11 in order to accurately position the solder paste, there is an advantage that the cream solder can be accurately applied. Similarly, with respect to the electronic component mounting process, with respect to the main board 11 having an inclination,
By arranging the recognition mark 14 on the main board 11, since the inclination of the electronic component land 15 and the inclination of the recognition mark 14 are proportional, there is an advantage that the center of the electronic component land can be accurately positioned. A chip component reflow soldering operation can be performed.

[0010]

As apparent from the above embodiment, the present invention comprises a main board on which electronic components are mounted, and a discarded board arranged around the main board and used as a guide for automatic mounting of components. By providing the recognition mark for detecting the substrate position on the main board, the position of the main board can be detected with respect to the circumferential displacement of the main board of the push-back type printed wiring board. The metal mask and the chip component land of the present substrate can be matched, and an excellent push-back type printed wiring board capable of performing an accurate chip component reflow soldering operation can be realized.

[Brief description of the drawings]

FIG. 1 is a plan view showing a schematic configuration of a push-back type printed wiring board according to an embodiment of the present invention.

FIG. 2 is a plan view showing a schematic configuration of a conventional push-back type printed wiring board.

[Explanation of symbols]

 Reference Signs List 10 push-back type printed wiring board 11 main board 12 outer discarded board (discarded board) 14 recognition mark

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masayoshi Suzuki 4-1-1 Tsunashima Higashi, Kohoku-ku, Yokohama-shi, Kanagawa Prefecture Inside Matsushita Communication Industrial Co., Ltd. (56) Reference Real Opening 2-101563 (JP, U) Japanese Utility Model Application Sho 64-44663 (JP, U) Japanese Utility Model Application Hei 2-41473 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H05K 1/02

Claims (1)

(57) [Claims] 1. A wiring for mounting an electronic component.
The present circular of the substrate, after the electronic component mounting of the to the present substrate is used as a guide when the electronic component mounting to the substrate
With a discarded substrate to be removed from the substrate.
A printed circuit board, wherein the main board is a circular hollow penetrating a part of the main board.
Part, wherein the discarded substrate is a first member fitted into the hollow portion of the main substrate.
And a second discarded fitting fitted on the outer periphery of the main board.
And a substrate Te, the circumferential deviation of the present substrate and the second discarded substrate
To prevent the outer periphery of the main substrate and the second discard substrate
Some of the inner periphery of each have a straight portion to be fitted to each other, the straight portion, for viewing the circumferential deviation
Visual marks are provided on the main board and the second discarded board.
Only, further said first abandoned substrate to the present on the substrate and the second
To detect the inclination of the main board with respect to the discarded board
A push-back type printed circuit board provided with a plurality of recognition marks.