| 摘要 |
<p>PURPOSE:To keep the temperature of a horn, which abuts against a plastic ring, constant and consequently prevent the frictional heat from being built up in the horn by a method wherein cooling air is blasted through the air jets of a cooling air pipe, which is arranged at the peripheral part of the horn. CONSTITUTION:A cooling air pipe 51 annularly surrounding a horn above the tip part, which abuts against a plastic ring 2, of the horn 49. The cooling air pipe 51 is bonded through a proper bracket 52 to the horn 49 so as to be vertically movable together with the horn 49. A large number of air jets 52 are bored on the side, which faces to the horn 49. The tip part of the horn 49 of a supersonic vibration device 48 fits to the inner peripheral surface of the plastic ring 2 so as to vibrate the plastic ring 2 at a super high speed in order to melt the projecting strips of the plastic ring 2 by the frictional heat and to bond the ring to an interior finish film 1a. Though the generated frictional heat is transmitted to the tip part of the horn 49, since the horn 49 is cooled at all times by the air blasted from the cooling air pipe 51 through the jets 52 to the horn, no heat build-up in made on the horn 49 even after the continuous welding of a large number of plastic rings 2 with the horn.</p> |
