Patent ID: 7032589

Claim:
A portable ventilator for providing an air-recipient with compulsory inspiration, comprising: at least one compressor for controllably supplying compressed air along an output air path of the ventilator in an upstream to downstream direction towards the air recipient; an outlet manifold located along the ventilator output air path downstream from the at least one compressor and in direct flow communication therewith; and a single-expansion-chamber outlet muffler located along the ventilator output air path downstream from the outlet manifold and in direct flow communication with the air-recipient and with the manifold outlet, whereby the compressed air from the compressor passes through the manifold outlet, the muffler and then an inhale port of the muffler toward the air-recipient, the muffler and the manifold outlet being configured so that airflow through the inhale outlet port of the muffler is substantially pulse free and a transmission loss, defined as the ratio of sound power generated by the at least one compressor and incident on the outlet muffler to the sound power transmitted by the muffler, is sufficient to deaden the sound power of the at least one compressor.