PURPOSE: To make high-precision decision for defect of a joint, where impulsive force is made fixed, possible, by keeping the gap between the vibration center position at the tip of a vibrator and each lead terminal constant in the method where the vibrator is brought into contact with the connection part of lead terminals, which are connected on a substrate, to decide whether connection is defective or not.
CONSTITUTION: Connection joint 7 of lead terminals 4 is swept by vibrator 3, which is made into one body together with vibration applying equipment 1 and piezo-electric pickup 2, while moving table 8 where print substrate 6 is put. For the purpose of controlling the gap between lead terminal 4 and the tip of vibtator 3, probe 11 for contact-type displacement meter is caused to run first, and a difference for the set gap is fed back to step motor 12, and the gap is so adjusted that it may be the set value by moving vertically vibration applying equipment 1. Step motor 12 changes at 1.8° per one pulse, and vertically finely moving screw 13 changes by 2.5μm at this time. A bearing mechanism is provided between vibration applying equipment 1 and fixed frame 14, and the stand of vibration applying equipment 1 is not turned but moved only vertically.
YASUDA TOMIROU
EZAKI SATORU
