Patent ID: 7770694

Claim:
Resonator arrangement in an acoustic muffler for a refrigeration compressor mounted in the interior of a hermetic shell, said acoustic muffler comprising: a hollow body defining at least one dampening chamber which carries a gas inlet duct having an inlet opening outside the dampening chamber; an outlet opening inside the dampening chamber; a gas outlet duct presenting an inlet opening inside the dampening chamber; an outlet opening outside said dampening chamber, each said gas duct presenting a respective length and having a respective wall thickness; wherein at least one of the gas inlet and gas outlet ducts carries, extending along at least part of its length, a respective plurality of resonant ducts, each resonant duct presenting a first end, open to the interior of the respective gas duct and a second end, opposed to and spaced from the first end, each said resonant duct being dimensioned to present a determined length and a determined diameter, which are calculated to define a certain reactive impedance and a certain dissipative impedance for the acoustic muffler, in a determined frequency band.