Design method of ultrasonic tooling and ultrasonic welding line

When ultrasonic welding has damage lines on the surface of the tooling, or its shape is more or less different from that of ultrasonic plastic parts, ultrasonic welding will leave scars on the surface of ultrasonic plastic parts. Avoid the method is: in the ultrasonic tooling and ultrasonic plastic parts between the surface of the pad film.

Ultrasonic welding mold
Ultrasonic plastic parts tooling contact surface is at least larger than ultrasonic welding surface, and try to be positive ultrasonic welding position. Too small ultrasonic welding contact surface will cause larger damage and deformation, and not ideal ultrasonic welding effect.

Injection molded parts can be designed in any shape, but ultrasonic tooling cannot be made arbitrarily. The shape and length may affect the frequency and amplitude of ultrasonic welding joint. The design of ultrasonic tooling requires a reference surface, that is, the reference frequency surface determined by the frequency of the workpiece. The reference frequency surface generally accounts for more than 70% of the surface area of the welding head, so the shape of the protrusion on the surface of the injection parts is better than 30% of the whole plastic. Smooth, circular transition plastic surface, this standard can be appropriately relaxed. And the prominent position as far as possible in the ultrasonic plastic parts in the middle or symmetrical design.

Welding wire is the part where ultrasonic waves melt directly. There are two basic design methods:
① Shear design
② Energy guidance

All other variations fall into these two types or a mixture of them.