In the design of machines and mechanical systems a great deal can be achieved with regard to reduction of noise. For any particular operation or precess complete elimination of the noise producing forces is impossible, since these forces (such as combustion forces in engines, magnatic forces of motor, impact forces in punching and hammering operations, and cutting forces in many metal working processes) are essential to the operation or process. Quiet designs requires that impact and rattle between components should be avoided ; reciprocating movements should be braked gently; metal component should be exchanged with quieter plastic, nylon or composit components ; noisy components or processes should be enclosed; power sources and transmissions which give quiet speed regulation should be chosen ; vibration sources within the macine should be isolated ; cover panels and inspection hatches should be stiffened and well damped and machines should be provided with adequate cooling fins which reduce the need for air flows, and therefore the need for fans which are noisy. Processes that produces impulsive forces, such as hammering, punching and pressing operations, are very important class of noise produces. The most effective method of control is to replace the inpulsive force by a steadily applied force that will achieve the same effect. Examples are the relatively quiet breaking of concrete where a bending action is used rather than percissive methods and the use of steady squeezing forces rather than impulsive hammering to insert riverts into sheet metal work.
.
Custom Search