| 摘要 |
1,219,894. Seaming non-metallic sheet material. RADYNE Ltd. 25 April, 1968 [28 April, 1967], No. 19668/67. Heading B5K. Ultrasonic welding apparatus comprises a vibrator 3 for transmitting ultrasonic vibrations to the surface of a workpiece and mounted within a housing 2 which includes an end portion 6 resiliently connected to the body of the housing, the end portion 6 extending coaxially around the tip of the vibrator 5 such that, during a welding operation, when the tip is in contact with a workpiece, pressure is resiliently applied to the workpiece, around the area being welded, through the end portion 6. As shown, a magnetostrictive or piezo-electric transducer 1 is mounted in the housing 2 and is bonded to an exponential velocity transformer 3 mounted at its nodal point on flanges 4 secured to the housing 2. An intermediate half wavelength coupling stub may be included between the transducer 1 and the transformer 3. The tubular end portion 6 is resiliently connected to the housing 2 by a compression spring 7, an adjusting nut 8 and a locking nut 9. The nut 8 is set so that the tip of the transformer 3 does not project beyond the outer edge 11 of a ring- shaped locating shoe 12. In operation, when pressure is applied to the body of the housing 2, the tip moves downwards through an aperture 13 in the shoe. The transducer is energized by a trigger switch in the handle of the tool. The actuating arm of a microswitch 14, which is normally closed and is in series with the trigger switch, rests on a cam ring 15 and when the tip has progressed a predetermined distance into the workpiece the contacts of the microswitch are opened to de-energize the transducer 1. |
