Patent ID: 7837431
Filing Date: 2010-11-23
Classification: F04D

Abstract:
1. A substantially cylindrical impeller in which an inlet is formed at one end of the impeller, an outlet is formed at an outer periphery on another end side and a spiral channel connecting the inlet and the outlet is defined and formed inside of the impeller, comprising: a flange portion which protrudes outward in a radial direction from the outer periphery at a part nearer the inlet than the outlet, and which partitions the cylindrical impeller into an inlet side and an outlet side; a primary vane that defines the spiral channel, wherein the spiral channel is a channel starting from the inlet and extending around and along a rotary shaft of the impeller; and a secondary vane which is formed in a shape such that a part of the outer periphery on the outlet side with respect to the flange portion is gouged inward, and which defines a secondary channel connected to the spiral channel and extending around the outer periphery, wherein the primary and secondary vanes are connected to each other so as to provide an abrupt transition between a wall of the primary vane and a wall of the secondary vane.