Patent ID: 7748970
Filing Date: 2010-07-06
Classification: F04C

Abstract:
1. A vacuum pump comprising: a stator including a cylinder wall, and a pair of diaphragms, the cylinder wall having opposite ends, and the diaphragms disposed at the ends of the cylinder wall, respectively, such that respective inner surfaces of the cylinder wall and diaphragms delimit a pump chamber of the stator; a rotary shaft passing through the diaphragms, the rotary shaft having a passageway therein that extends into the pump chamber from outside the stator and defines a fluid supply path; and a lobe attached to the rotary shaft and extending radially outwardly therefrom in the pump chamber, wherein the lobe has side surfaces that face the diaphragms, respectively, the side surfaces of the lobe have at least one fluid port therein, each of said at least one fluid port confronts the inner surface of one of the diaphragms, and the at least one port is connected to the passageway so as to be in communication with the fluid supply path, whereby fluid fed along the fluid supply path discharges through each said at least one port towards the inner surface of one of the diaphragms.