| 摘要 |
Two plastic pieces such as a handle and a container are welded together using an ultrasonic horn. Protrusions serving as energy directors are arranged on one piece in a substantially circular array, in a starburst design. A hole or cavity is formed at a central axis of the circular array so that the amount of energy concentrating at inner ends of the energy directors will not create a burned spot or a hole in the container. The ultrasonic energy at the inner ends of the protrusions is concentrated at the smaller inner area defined by the inner ends of the protrusions to first melt inner ends of the protrusions and then the entire protrusions. |
