US Patent 7210295 Compressor with secondary boost air outlet passage

A wastegated turbocharger includes a turbine wheel mounted to a shaft for rotation within a turbine housing and a compressor wheel mounted to the shaft for rotation within a compressor housing. The compressor housing has mounted thereto a wastegate actuator command valve. A secondary boost air outlet passage is disposed in fluid flow communication with the wastegate actuator command valve and the compressor outlet volute. The secondary boost air outlet passage extends into the compressor outlet volute so that an inlet opening of the passage is spaced from the surface of the compressor outlet volute.