Centrifugal pump apparatus

摘要

A centrifugal blood pump apparatus includes an impeller provided in a blood chamber, first and second permanent magnets provided in one surface and the other surface of the impeller respectively, a third permanent magnet provided in an inner wall of the blood chamber, and a magnetic element and a coil for driving the impeller to rotate with a diaphragm being interposed. First and second grooves for hydrodynamic bearing different in shape and depth from each other are formed in the inner wall of the blood chamber facing the impeller, and third and fourth grooves for hydrodynamic bearing different in shape and depth from each other are formed in the diaphragm facing the impeller. The second and fourth grooves for hydrodynamic bearing generate high hydrodynamic pressure when the impeller is activated to rotate, while the first and third grooves for hydrodynamic bearing generate high hydrodynamic pressure when the impeller steadily rotates.

主权项

1. A centrifugal pump apparatus including a housing having first and second chambers partitioned from each other by a diaphragm, an impeller rotatably provided in said first chamber along said diaphragm, for delivering liquid by centrifugal force during rotation, and a drive unit provided in said second chamber for driving said impeller to rotate with said diaphragm being interposed, comprising:
a first magnetic element provided in a first surface of said impeller; a second magnetic element provided in a planar surface of said first chamber facing the first surface of said impeller, for attracting said first magnetic element; a third magnetic element provided in a second surface of said impeller and attracted by said drive unit during rotation of said impeller, a first attractive force between said first and second magnetic elements and a second attractive force between said third magnetic element and said drive unit causing said impeller to be located substantially in a center of a movable range of said impeller in said first chamber; a plurality of first grooves and a plurality of second grooves, wherein:
said plurality of first grooves and said plurality of second grooves are formed in said planar surface of said first chamber facing said first surface of said impeller;said plurality of first grooves alternate with and are separate from said plurality of second grooves;said plurality of first grooves begin at a first outer diameter and end at a first inner diameter; andsaid plurality of second grooves begin at the first outer diameter and end at the first inner diameter; and a plurality of third grooves and a plurality of fourth grooves, wherein:
said plurality of third grooves and said plurality of fourth grooves are formed in a planar surface of said diaphragm facing said second surface of said impeller;said plurality of third grooves alternate with and are separate from said plurality of fourth grooves;said plurality of third grooves begin at a second outer diameter and end at a second inner diameter; andsaid plurality of fourth grooves begin at the second outer diameter and end at the second inner diameter, wherein at least one of a width and a depth of said plurality of second grooves is different from that of said plurality of first grooves, and at least one of a width and a depth of said plurality of fourth grooves is different from that of said plurality of third grooves.