7.Printed Circuit Board Cropping

1. After mounting a capacitor on a printed circuit board, do not apply any stress to the capacitor that is

caused by bending or twisting the board.

1-1. In cropping the board, the stress as shown right may cause the capacitor to crack.

Try not to apply this type of stress to a capacitor.

Bending

Twisting

2. Check of the cropping method for the printed circuit board in advance.

2-1. Printed circuit board cropping shall be carried out by using a jig or an apparatus to prevent the

mechanical stress which can occur to the board.

(1) Example of a suitable jig

Recommended example: the board should be pushed as close to the near the cropping jig as possible

and from the back side of board in order to minimize the compressive stress applied to capacitor.

Not recommended example* when the board is pushed at a point far from the cropping jig and from

the front side of board as below, the capacitor may form a crack caused by the tensile stress applied

to capacitor.

Outline of jig

(2) Example of a suitable machine

An outline of a printed circuit board cropping machine is shown as follows. Along the lines with the

V-grooves on printed circuit board, the top and bottom blades are aligned to one another when

cropping the board.

The misalignment of the position between top and bottom blades may cause the capacitor to crack.

Outline of machine

Principle of operation

Cross-section diagram

Top blade

Top blade

Top blade

Top blade

Bottom blade

Bottom blade

Bottom blade

Bottom blade

Caution

Recommended

Not recommended

Top-bottom misalignment

Left-right misalignment

Front-rear misalignment

Recommended

Not recommended

Printed circuit

board

V-groove

Board cropping jig

Printed circuit board

Top blade

V-groove

Bottom blade

Top blade

Printed circuit board

V-groove

!

①

1A

Printed circuit

board

Components

Load point

Direction of

load

Printed circuit

board

Component

s

Load point

Direction of load

JEMCCC-0010Q

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