Patent ID: 9303645
Filing Date: 2016-04-05
CPC Classification: F04D

Claim Text:
1. A regenerative blower, comprising: an impeller, the impeller is rotatable about an axis of rotation; an annular housing assembly surrounds the impeller and has a toroidal flow channel for a fluid, an inlet to admit fluid to the toroidal flow channel, and an outlet to discharge fluid from the toroidal flow channel, the toroidal flow channel extends through the annular housing assembly from the inlet to the outlet; the impeller extends radially outward from the axis of rotation to blades that reside in the toroidal flow channel, and includes an upper side and a lower side; the blades rotate through the toroidal flow channel forcing fluid through the toroidal flow channel from the inlet to the outlet, when impeller rotates about the axis of rotation; a low fluid-pressure region of the toroidal flow channel proximate to the inlet, and an opposed high fluid-pressure region of the toroidal flow channel proximate to the outlet; and opposed concentric surface contours of the upper side and the lower side of the impeller and the annular housing assembly extend transversely relative the axis of rotation of the impeller in a direction from the high fluid-pressure region of the toroidal flow channel to the low fluid-pressure region of the toroidal flow channel and are located between the toroidal flow channel and the axis of rotation of the impeller, the opposed concentric surface contours of the upper side and the lower side of the impeller and the annular housing assembly non-contact interact to form opposed concentric fluid pathways between the upper side and the lower side of the impeller and the annular housing assembly from the high fluid-pressure region of the toroidal flow channel to the low fluid-pressure region of the toroidal flow channel, the opposed concentric fluid pathways being so convoluted as to restrict fluid from flowing therethrough from the high fluid-pressure region of the toroidal flow channel through the annular housing assembly across a region of the axis of rotation of the impeller to the low fluid-pressure region of the toroidal flow channel.