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Pi Type Ferrite Magnetostrictive Vibrators - 34778 The next part describes Fig.20 (c).Fig.20 (d) can be considered to be a part of (c) as it is only an inverted version of (c). Fig.22 is an actual example with eight vibrators bonded to a vibrat-ing plate.A vibrating plate thickness of 0.5 to 1mm is suited for such applica- tions.Vibrating plates that are too thick reduce efficiency, and those that are too thin cannot withstand the vibrator’s weight, furthermore it compromises their erosion durability.In the example illustrated in Fig.22, a rubber packing must be inserted between the vibrating plate and frames (Vibrators bonded directly to a container’s bottom without the use of rubber packing will cause the entire container to become acoustically active, which is not undesirable).Attaching a non-vibrating element too close to the container’s perimeter can lead to adhesive separation or irregular frequencies. This is because the vibrating plate may become deformed by the tightening of screws when attaching it to the container.

Fig.22

In the preceding sections we have described ways in which the vibrators can be used primarily in ultrasonic cleaners. These vibra-tors have other applications including fish detectors and ultrasonic machining tools. For your information, we have included an example of how a fish detector is configured in Fig.23. The design must be such that the unit is able to withstand water pressure and mechanical shocks. Ultrasonic machining requires that a horn be used in conjunction with a vibrator. An important point in this application is the selec-tion of horn material and adhesives suited for ferrite cores. OTHER REMINDERS

Fig.23 Example of fish detector configuration

PRECAUTIONS IN HANDLING •The vibrators are made of ceramic. Please do not hit or drop them. Broken vibrators are irreparable.•Do not apply intense excitation in open air (i.e. without load). This includes removing an operating vibrator of a cleaner from the water and into open air with the power still on, and tuning vibrators in open air. In such situations, even a small output can amplify very quickly and lead to damage. This is also true for tuning vibrators without placing them in water.•If sponges are required, only use closed cell sponges. Because all of the cells in these sponges are independent of each other, they do not soak water and therefore do not transmit acoustic waves from the vibrator to the water. This creates a nearly loadless condition for the vibrator. Sponges that simulate natural sponges are not suited for this purpose.•Always make sure that the excitation magnets are used in their proper polarity.

• All specifications are subject to change without notice.