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

摘要

A shunt pulsation trap for a rotary lobe blower (pump) or vacuum pump reduces pulsation and NVH, and improves efficiency, without increasing overall size of the blower or pump. A rotary lobe blower (pump) or vacuum pump has a pair of synchronized parallel multi-lobe rotors that are housed in a transfer chamber and that propel flow from a suction port to a discharge port of the transfer chamber. The shunt pulsation trap includes an inner casing as an integral part of the transfer chamber, and an outer casing oversized and surrounding the inner casing. The shunt pulsation trap houses at least one various pulsation dampening device, and includes at least one injection port (trap inlet) branching off from the transfer chamber into the pulsation trap chamber and at least one feedback port (trap outlet) communicating with the blower outlet pressure.

主权项

1. A rotary blower, comprising:
a. a housing structure having an inner casing with a flow suction port, a flow discharge port, and a transfer chamber there-between; b. two parallel multi-lobe rotors having a same number of lobes defining lobe spans and rotatably mounted on two parallel rotor shafts respectively inside said transfer chamber and synchronously driven for propelling flow from said suction port to said discharge port in a flow direction; c. a shunt pulsation trap apparatus comprising an outer casing oversized and surrounding said inner casing to cooperatively form a pulsation trap chamber therebetween, at least one pulsation dampening device positioned within the pulsation trap chamber, at least one trap inlet branching off from said transfer chamber at least one lobe span away from said flow suction port in said flow direction and connecting said transfer chamber to said pulsation trap so that at least a portion of said transfer chamber and said pulsation trap chamber are arranged in parallel, and at least one trap outlet connecting said pulsation trap chamber to said discharge port;wherein in operation said rotary blower achieves reduced pulsation and NVH at said pulsation trap chamber and improved blower efficiency.