Patent ID: 6935551

Claim:
An ultrasonic bonding method of coated electric wires for intersecting coated electric wires with each other, and bonding intersected portions of the coated electric wires to each other by ultrasonic vibration, the ultrasonic bonding method comprising: a sandwiching step for sandwiching the intersected portions of the coated electric wires between a horn-side chip and an anvil-side chip; an insulator-melting step for applying ultrasonic vibration force determined by a first vibration condition to the horn-side chip, and melting insulators of the coated electric wires; a conductor contact-detecting step for automatically detecting a time point when the insulators are melted and conductors of the coated electric wires come into contact with each other; and a conductor-bonding step for applying ultrasonic vibration force determined by a second vibration condition to the horn-side chip after the conductors came into contact with each other, thereby bonding the conductors to each other.