| 摘要 |
PURPOSE:To suppress leakage of gas by mounting a tension plate for pressing the section of an elastic sheet except a notched section uniformly against a vane between the elastic sheet and an elastic member. CONSTITUTION:Pressure A at the side of a delivery chamber 16 is higher than the pressure B in a suction chamber 15 arranged at the opposite side. A vane 7 is subjected to force in reverse direction from the side where a notch 32 is formed in an elastic sheet 30 and thereby the vane 7 moves toward a slit side face 17 at the delivery side and contacts with the slit end face 14. Since the space 19 between a tension plate 13 and a slit 8 is communicated through the notched section 32 with the chamber 16 in a cylinder at the delivery side, the pressure in the space 19 is maintained at a level approximately equal to that in the chamber 16. |
