Conductor connection device and conductor connection method

A conductor connection method comprising the steps of:

• disposing a plurality of conductors in a space formed by a horn including a first contact surface that is brought into contact with the conductors, the horn being configured to be ultrasonically vibrated, and a pair of restricting portions each having a second contact surface that is brought into contact with the first contact surface and is disposed facing each other at a predetermined interval, the pair of restricting portions being relatively moved along the first contact surface, wherein the first and second contact surfaces each have engagement features having complementary shapes that are configured to maintain contact engagement between the first and second contact surfaces during relative movement of the second contacts surfaces along the first contact surface;
• moving the horn and the pair of restricting portions relative to an anvil disposed at a predetermined interval with respect to the first contact surface while moving at least one of the pair of restricting portions relatively toward the other of the pair of restricting portions, and while maintaining contact engagement between the first and second contact surfaces, to sandwich the anvil between the pair of restricting portions facing each other, and compressing the conductors with the anvil and the horn with the pair of restricting portions sandwiching the anvil;
• and
• welding the conductors compressed by the anvil and the horn with ultrasonic welding by ultrasonically vibrating the horn.