Rotation drive device and centrifugal pump apparatus employing same

A centrifugal pump apparatus including a housing having first and second chambers partitioned from each other by a dividing wall, an impeller provided in said first chamber along said dividing wall, for delivering fluid by centrifugal force during rotation, and a drive unit provided in said second chamber for driving said impeller to rotate with said dividing wall interposed therebetween, said centrifugal pump apparatus comprising:

• a plurality of first permanent magnets provided in said impeller and attracted by said drive unit, wherein
• said drive unit includes
• a plurality of magnetic elements arranged to face said plurality of first permanent magnets,
• a plurality of coils provided correspondingly to said plurality of magnetic elements respectively and each wound around the corresponding magnetic element, for generating a rotating magnetic field,
• a connector fixed to said housing and externally receiving a driving voltage, and
• a flexible substrate connected to said plurality of coils and said connector, wherein
• said flexible substrate comprises a strip which has a length at least partially arranged to surround the outer circumferences of said plurality of coils, and
• said flexible substrate comprises a plurality of electrodes connected with said plurality of coils, wherein said plurality of electrodes are arranged in pairs which are located along said length, each pair comprising two electrodes located side-by-side in an axial direction of the drive unit at a common distance along said length, and each pair of electrodes connected with two leads from one of the plurality of coils.