Abstract: An impeller includes a hub having a circular plate shape with an axial line as a center, a shroud disposed to face the hub in a direction of the axial line, and a plurality of blades disposed with a space from each other in a circumferential direction between the hub and the shroud. A meridian plane shape of the impeller differs in the circumferential direction.

Abstract: A hub is supported rotatably about an axis of rotation, and the diameter thereof increases from upstream to downstream sides along a fluid flow. A plurality of impeller blades extend radially outward from an outer circumferential surface of the hub. A shroud is formed in a cylindrical shape whose diameter increases from the upstream to downstream sides along the fluid flow and joins outer circumferential ends of the plurality of impeller blades. The impeller blades are composed of upstream blade segments and downstream blade segments bonded at a bonding surface extending in a direction substantially perpendicular to the axis of rotation. The upstream blade segments are integral with at least a portion of the shroud, and the downstream blade segments are integral with at least a portion of the hub. This improves the reliability and performance of an impeller and a compressor.

Abstract: A manufacturing method of an impeller includes forming a plurality of blades integrally on a blade attachment surface of one of a disc and a cover, placing the cover on a floor so as to face up the blade attachment surface of the cover, disposing the disc on the cover so as to face down the blade attachment surface of the disc, and bonding the plurality of blades to the blade attachment surface of the other of the disc and the cover which is not formed integrally with the plurality of blades by using a bonding material.

Abstract: A hub is supported rotatably about an axis of rotation, and the diameter thereof increases from upstream to downstream sides along a fluid flow. A plurality of impeller blades extend radially outward from an outer circumferential surface of the hub. A shroud is formed in a cylindrical shape whose diameter increases from the upstream to downstream sides along the fluid flow and joins outer circumferential ends of the plurality of impeller blades. The impeller blades are composed of upstream blade segments and downstream blade segments bonded at a bonding surface extending in a direction substantially perpendicular to the axis of rotation. The upstream blade segments are integral with at least a portion of the shroud, and the downstream blade segments are integral with at least a portion of the hub. This improves the reliability and performance of an impeller and a compressor.

Abstract: A manufacturing method of an impeller includes: forming a plurality of blades integrally on a blade attachment surface of one of a disc and a cover; placing the cover on a floor so as to face up the blade attachment surface of the cover; disposing the disc on the cover so as to face down the blade attachment surface of the disc; and bonding the plurality of blades to the blade attachment surface of the other of the disc and the cover which is not formed integrally with the plurality of blades by using a bonding material.

Abstract: An artificial cardiac pump includes an impeller (3) rotatably supported on a fixed shaft body (2) in a housing (1) and a drive mechanism rotating the impeller, wherein blood is taken in from the front side and force-fed to the rear side by the rotation of the impeller (3). The shaft body (2) is connected between a front side fixed body (5) fixed to a straightening plate (4) joined to the housing (1) at the front of the impeller (3) and a rear side fixed body (7) fixed to a diffuser (6) joined to the housing (1) at the rear of the impeller (3). The impeller (3) further includes a sleeve (8) having an inner peripheral surface opposed to the outer peripheral surface of the shaft body (2) through a minute clearance and front and rear end faces opposed to the rear end face of the front side fixed body (5) and the front end face of the rear side fixed body (7) through minute clearances, and an impeller (9) joined to the outer peripheral surface of the sleeve (8).

Abstract: An artificial cardiac pump, comprising an impeller (3) rotatably supported on a fixed shaft body (2) in a housing (1) and a drive mechanism rotating the impeller, wherein blood is taken in from the front side and force-fed to the rear side by the rotation of the impeller (3). The shaft body (2) is connected between a front side fixed body (5) fixed to a straightening plate (4) joined to the housing (1) at the front of the impeller (3) and a rear side fixed body (7) fixed to a diffuser (6) joined to the housing (1) at the rear of the impeller (3). The impeller (3) further comprises a sleeve (8) having an inner peripheral surface opposed to the outer peripheral surface of the shaft body (2) through a minute clearance and front and rear end faces opposed to the rear end face of the front side fixed body (5) and the front end face of the rear side fixed body (7) through minute clearances, and an impeller (9) joined to the outer peripheral surface of the sleeve (8).

Abstract: An axial-flow pump employs an increased boss ratio Dh/Dt, wherein Dh is the hub diameter of a rotary shaft of a rotor, and Dt is the tip diameter of impeller vanes of the rotor. Specifically, the boss ratio is 0.65 to 0.85, preferably 0.7 to 0.8.