Rotary lobe blower (pump) or vacuum pump with a shunt pulsation trap

A rotary blower with a shunt pulsation trap apparatus, comprising:

• a. a housing structure having an inner casing with a flow suction port, a flow discharge port and a transfer chamber there-between, and at least one injection port located at least one lobe span away from said flow suction port communicating with said transfer chamber and at least one feedback port communicating with atmosphere, and an outer casing enclosing said inner casing;
• b. two parallel multi-lobe rotors having same number of lobes and rotatably mounted on two parallel rotor shafts respectively inside said inner casing and interconnected through a set of timing gears to rotate in synchronization for propelling flow from said suction port to said discharge port;
• c. a shunt pulsation trap apparatus comprising said inner casing as an integral part of said transfer chamber, and said outer casing oversized surrounding said inner casing, therein housed various pulsation dampening means or pulsation energy recovery means or pulsation containment means, at least one trap inlet (said injection port) branching off from said transfer chamber into said pulsation trap and at least one trap outlet (said feedback port) communicating with atmosphere;
• d. whereby said rotary blower is capable of achieving high pulsation and NVH reduction at source and improving blower efficiency without an externally connected silencer at discharge port or an externally connected silencer at feedback port or both while being kept light in mass, compact in size.