(under the class definition) Apparatus comprising means or a disposition of parts to eliminate, reduce or prevent the formation or transmission of sonic or oscillatory waves from the apparatus to the environment or between parts of the apparatus.
(1) Note. Examples of such means are: sound traps, nozzle shapes, absorbent material.
SEE OR SEARCH CLASS
60, Power Plants, appropriate subclasses, for a fluid motor* combined with means treating or handling the exhaust fluid for absorbing or damping sound or vibratory waves, see the Class Definition, References to Other Classes, above, Class 60, Power Plants, (8).
181, Acoustics,
200+, for the sound muffler or sound filter subcombination, per se.