Abstract: A film cleaning apparatus and method is disclosed where apparatus includes a feed reel and a take-up reel, and a film path created by a number of particle transfer rollers. Also in the film path is a region of high humidity followed by two buffing rollers for polishing the film to be cleaned. Two of the rollers are connected to a vibration generator mechanism. Vibration of the rollers is caused by a rotating disk having two embedded magnetic elements which pass closely adjacent to magnetic elements at the end of rollers' shafts. As the rotating magnets pass by the two shafts, a repulsion force causes the shafts to move away. Connected to each of the shafts is an O-ring which acts as a compression spring that biases its respective shaft back to its starting position after the magnetic elements have moved away from each other. By rotating the disk with the magnetic elements at 3600 rpm a vibration is set up in the shafts at a rate of 7200 times per minute.

Abstract: A noncontact ultrasonic transducer for studying the acoustic properties of a metal workpiece includes a generally planar magnetizing coil positioned above the surface of the workpiece, and a generally planar eddy current coil between the magnetizing coil and the workpiece. When a large current is passed through the magnetizing coil, a large magnetic field is applied to the near-surface regions of the workpiece. The eddy current coil can then be operated as a transmitter by passing an alternating current therethrough to excite ultrasonic waves in the surface of the workpiece, or operated as a passive receiver to sense ultrasonic waves in the surface by measuring the output signal. The geometries of the two coils can be varied widely to be effective for different types of ultrasonic waves. The coils are preferably packaged in a housing which does not interfere with their operation, but protects them from a variety of adverse environmental conditions.