Liquid ring vacuum pump
AssigneeEbara Corporation
InventorsHiroyuki Kawasaki, Nozomu Sasaki
Life of this patent
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Abstract
The present invention relates to a two-stage liquid ring vacuum pump in which two-stage impellers are attached to an axial end portion of a main shaft (rotating shaft) of a motor. The two-stage liquid ring vacuum pump includes a first-stage impeller (4) provided in a first-stage pump chamber (1), a second-stage impeller (5) provided in a second-stage pump chamber (2), a single rotating shaft (7) to which the first-stage impeller (4) and the second-stage impeller (5) are fixed, and an exhaust port (Pd) of the first-stage pump chamber (1) and an intake port (Ps) of the second-stage pump chamber (2) which communicate with each other. An outer diameter of the first-stage impeller (4) is larger than an outer diameter of the second-stage impeller (5).
Claims9
A liquid ring vacuum pump comprising:
- a casing for housing a sealing liquid;
- an exhaust casing covering a rear side opening of the casing;
- at least one impeller housed in the casing;
- and
- a shaft seal component provided in a portion where a main shaft for supporting the impeller passes through the exhaust casing;
- wherein the impeller comprises a cylindrical boss portion having a hole for allowing the main shaft to be inserted therein, a plurality of blades extending radially outwardly from the boss portion, and a circular ring-shaped side plate extending radially outwardly from an outer circumference of the boss portion and positioned at a side facing the shaft seal component;
- wherein an outer diameter of the side plate is larger than an inner diameter of a housing space, for housing the shaft seal component, formed in the exhaust casing;
- wherein the exhaust casing has an exhaust port formed therein;
- and
- wherein the side plate has an outer circumference located more inwardly than the exhaust port in the radial direction of the impeller.
Dependencies are inferred from the claim text.