| 摘要 |
<p>A METHOD USED IN PAPER MAKING FOR TREATMENT OF A WEAVE Ultrasonic frequency sensors are arranged in the vicinity of a material to be treated, on opposite sides of such material, opposite each other. In one embodiment, longitudinal acoustic vibrations are fed to the sensors at the same frequency and the phase difference of the vibrations fed to the different sensors is varied. In another embodiment, the vibrations are fed to the sensors at different frequencies f1 and f2 and the frequency difference .DELTA.f of the frequencies, where .DELTA.f = f1 - f2, is varied. In each embodiment the most intensive area of the field of vibration combinations in the material to be treated is focused in a manner whereby it has an effect upon a desired area of the material.</p> |
