A rotary blood pump includes a casing defining a pumping chamber. The pumping chamber has a blood inlet and a tangential blood outlet. One or more motor stators are provided outside of the pumping chamber. A rotatable impeller is within the pumping chamber and is adapted to cause blood entering the pumping chamber to move to the blood outlet. The impeller has one or more magnetic regions. The impeller is radially constrained in rotation by magnetic coupling to one or more motor stators and is axially constrained in rotation by one or more hydrodynamic thrust bearing surfaces on the impeller.

A rotary blood pump includes a casing defining a pumping chamber. The pumping chamber has a blood inlet and a tangential blood outlet. One or more motor stators are provided outside of the pumping chamber. A rotatable impeller is within the pumping chamber and is adapted to cause blood entering the pumping chamber to move to the blood outlet. The impeller has one or more magnetic regions. The impeller is radially constrained in rotation by magnetic coupling to one or more motor stators and is axially constrained in rotation by one or more hydrodynamic thrust bearing surfaces on the impeller.

In an exemplary embodiment, a seal device (10) that seals between a housing (11) and a rotation shaft (20) passing through the housing (11) includes: a floating ring (15) arranged with a gap h with respect to the rotation shaft (20), a seal portion (14) formed by bringing one end face of the floating ring (15) into contact with the housing (11), and a space portion j provided between the floating ring (15) and the housing (11), and the floating ring (15) includes bias means that contactlessly biases the floating ring (15) to the seal portion via the space portion j. The seal device in which the floating ring follows movement of the rotation shaft is capable of exerting a sealing operation so that vibration of the rotation shaft can be reduced.

A pump includes: a rotor; a magnetic bearing supporting the rotor by a magnetic force; a drive mechanism rotationally driving the rotor; a pump mechanism including an impeller attached to the rotor; and a control unit controlling the magnetic bearing which includes: a bearing rotor member in the rotor formed from a magnetic material; and a bearing stator member facing the bearing rotor member, the bearing stator member has: a core formed from a magnetic material; and a coil wound around the core, the drive mechanism includes: a driven member adjacent in a radial direction to the bearing rotor member; and a drive portion facing the driven member in the radial direction, and magnetically coupled to the driven member to drive the rotor, and the control unit corrects rotational position of the rotor based on a detection signal from a first sensor portion capable of detecting displacement of the rotor.

A pump includes: a rotor; a magnetic bearing supporting the rotor by a magnetic force; a drive mechanism rotationally driving the rotor; a pump mechanism including an impeller attached to the rotor; and a control unit controlling the magnetic bearing which includes: a bearing rotor member in the rotor formed from a magnetic material; and a bearing stator member facing the bearing rotor member, the bearing stator member has: a core formed from a magnetic material; and a coil wound around the core, the drive mechanism includes: a driven member adjacent in a radial direction to the bearing rotor member; and a drive portion facing the driven member in the radial direction, and magnetically coupled to the driven member to drive the rotor, and the control unit corrects rotational position of the rotor based on a detection signal from a first sensor portion capable of detecting displacement of the rotor.

A vacuum pump and a washer which can reduce vibration of a rotor and the rotor which can reduce the vibration are provided. When an inertia moment ratio which is a ratio between the inertia moment around a z-axis and the inertia moment around an x-axis or a y-axis is larger than 1, a natural frequency ω.sub.2 does not match a rotational frequency Ω.sub.z but goes away from that. When the natural frequency ω.sub.2 matches the rotational frequency Ω.sub.z, the rotor vibrates and thus, a fatigue failure occurs in a rotor blade. When the rotor is to be made larger in a radial direction of a rotating shaft, a value of the inertia moment ratio is set to a value larger than 1.

A vacuum pump and a washer which can reduce vibration of a rotor and the rotor which can reduce the vibration are provided. When an inertia moment ratio which is a ratio between the inertia moment around a z-axis and the inertia moment around an x-axis or a y-axis is larger than 1, a natural frequency ω.sub.2 does not match a rotational frequency Ω.sub.z but goes away from that. When the natural frequency ω.sub.2 matches the rotational frequency Ω.sub.z, the rotor vibrates and thus, a fatigue failure occurs in a rotor blade. When the rotor is to be made larger in a radial direction of a rotating shaft, a value of the inertia moment ratio is set to a value larger than 1.

The present invention relates to a motor pump (10) free from bearings, cooler and mechanical sealing, more specifically to a hydraulic motor pump, which comprises a housing (14) defined by a first chamber (19) isolated from fluids and a second chamber (17). In the second chamber (17) there is an integral rotor/turbine assembly (11), the rotor and the turbine being induced by magnetic forces of a stator (12), which is located in the first chamber (19). A fluid inlet (15) and a fluid outlet (16) are located at the same end of the motor pump (10), so that most of the fluid impelled into the motor pump (10) is guided directly to the outlet (16) with the aid of a fluid guide (20) located at the front end (24) of the rotor/turbine assembly (11), enabling an increase in the flowrate inside the motor pump (10), thus increasing the yield thereof.

The present invention relates to a motor pump (10) free from bearings, cooler and mechanical sealing, more specifically to a hydraulic motor pump, which comprises a housing (14) defined by a first chamber (19) isolated from fluids and a second chamber (17). In the second chamber (17) there is an integral rotor/turbine assembly (11), the rotor and the turbine being induced by magnetic forces of a stator (12), which is located in the first chamber (19). A fluid inlet (15) and a fluid outlet (16) are located at the same end of the motor pump (10), so that most of the fluid impelled into the motor pump (10) is guided directly to the outlet (16) with the aid of a fluid guide (20) located at the front end (24) of the rotor/turbine assembly (11), enabling an increase in the flowrate inside the motor pump (10), thus increasing the yield thereof.

A pump unit for a centrifugal pump includes a pump housing with an inlet and with an outlet for a fluid to be conveyed, and a rotor arranged in the pump housing to convey the fluid, the rotor configured to be rotated about an axial direction, the pump unit capable of non-contact magnetic levitation of the rotor and non-contact magnetic drive of the rotor by a stator. The pump housing has a cover part and a bottom part to enclose the cover part, the bottom part having a cylindrical cup to receive the rotor, the cylindrical cup configured to be inserted into the cup-shaped recess of the stator. Both the inlet and the outlet of the pump housing are arranged at the cover part.