| 摘要 |
<p>PURPOSE:To prevent the swelling of a disk due to the pressure of sealed air by forming a vent communicating space partitioned by an ultrasonic horn body and the surface of an optical disk with the outside air to the ultrasonic horn body between internal and external annular-shaped machining surfaces on which an ultrasonic horn is brought into contact with the disk. CONSTITUTION:Two disks 3, 4 mutually welded by ultrasonic waves are placed onto a lower cradle 2 under the state in which they are fitted to a center pin 6 for centering. Annular-shaped ribs are formed to at least one circumferential section and outer circumferential section of the disks 3, 4. Minute projections called an energy director are shaped to at least one of said annular-shaped ribs, and melting is started from said energy directors by ultrasonic energy applied through the machining surfaces 10, 11 of an ultrasonic horn body 1. Vents 20 communicating with a space 7 partitioned between the disk 3 and the horn body 1 are formed to the horn body 1 in order to communicate the space 7 with the outside air, and the vents 20 communicates with slots 21 normally shaped to the ultrasonic horn body 1.</p> |
