Patent ID: 8469654
Filing Date: 2013-06-25
Classification: F04D

Abstract:
1. A rotary-type fluid machine having an impeller integrally connected to a rotating drive shaft; a casing for accommodating the impeller; and an intake port for fluid to be fed under pressure, which is provided so as to face a radially center portion of the impeller; the fluid machine comprising: many grooves extending radially outward from the radially center portion of the impeller, which are formed at angular intervals in a side surface of the impeller positioned on its side facing the intake port and opposed against a stationary wall surface of the casing, the angular interval being equal to or less than an angle of 10 degrees, wherein the grooves open toward the stationary wall surface, extend toward an outer circumferential edge of the impeller from a region radially inward of the intake port and open on an outer circumferential surface of the impeller; wherein a gap between the side surface of the impeller and a side wall surface of the casing has a dimension (q) equal to or greater than 0.4 mm or an impeller diameter (d wherein each of the grooves has a depth (h) equal to or greater than 0.4 mm or the impeller diameter (d