摘要 |
A stator (1) has a circular cylindrical internal surface (3) delimiting an operating chamber. A rotor (4) is mounted so as to be rotatable about the axis (8) of the internal surface (3) and has a cylindrical external surface (11), with one generatrix (13) adjacent to the internal surface (3), a diametrically opposite generatrix being spaced from the internal surface. A sealing member (17), projecting through a slot in the stator (1) into the operating chamber and being movable substantially radially, has an axial length substantially equal to that of the rotor (4). The sealing member (17) is connected to the rotor (4) by a linkage which causes the radially inner end of the sealing member to closely follow the external surface (3). A shutter disc (6) at one end of the rotor (4) covers a port (14), in particular an inlet port, in the stator (1). The disc (6) has a through-hole with a first end remote from the operating chamber and a second end opening into the operating chamber, the first end periodically overlapping the port (14) as the rotor (4) rotates. |