A blood flow assist system can include an impeller assembly including an impeller shaft and an impeller on the impeller shaft, a primary flow pathway disposed along an exterior surface of the impeller. The system can include a rotor assembly at a proximal portion of the impeller shaft. A secondary flow pathway can be disposed along a lumen of the impeller shaft. During operation of the blood flow assist system, blood can be pumped proximally along the primary flow pathway and the secondary flow pathway. The system can include a sleeve bearing distal the impeller. The system can include a drive unit having a distal end disposed distal a proximal end of the second impeller. The drive unit comprising a drive magnet and a drive bearing between the drive magnet and the impeller assembly.

A pump may include a stator, a rotor, and an impeller. The stator may include one or more electromagnets and one or more permanent magnets. The rotor may include an armature, one or more complementary permanent magnets, and a pull magnet configured to position the rotor in an axial direction. The rotor may be disposed within the stator. The complementary permanent magnets and the one or more permanent magnets of the stator may create magnetic bearings. The armature may be aligned with at least one of the electromagnets of the stator and configured to rotate the rotor with respect to the stator. The impeller may be coupled to the rotor.

A blood flow assist system can include an impeller assembly including an impeller shaft and an impeller on the impeller shaft, a primary flow pathway disposed along an exterior surface of the impeller. The system can include a rotor assembly at a proximal portion of the impeller shaft. A secondary flow pathway can be disposed along a lumen of the impeller shaft. During operation of the blood flow assist system, blood can be pumped proximally along the primary flow pathway and the secondary flow pathway. The system can include a sleeve bearing distal the impeller. The system can include a drive unit having a distal end disposed distal a proximal end of the second impeller. The drive unit comprising a drive magnet and a drive bearing between the drive magnet and the impeller assembly.

Described herein are appliances such as a vacuum cleaners having an air flow passage and a fan assembly provided in the air flow passage. The fan assembly includes (a) a first motor comprising a first rotor, a first stator, and a first rotatable output shaft drivingly connected to the first rotor; and (b) a second motor comprising a second rotor, a second stator, and a second rotatable output shaft drivingly connected to the second rotor. The first rotatable output shaft is driving connected to the second stator; and a fan blade drivingly connected to the second rotatable output shaft. Also described herein are methods of energizing a fan assembly of a portable appliance.

A blood flow assist system can include an impeller assembly including an impeller shaft and an impeller on the impeller shaft, a primary flow pathway disposed along an exterior surface of the impeller. The system can include a rotor assembly at a proximal portion of the impeller shaft. A secondary flow pathway can be disposed along a lumen of the impeller shaft. During operation of the blood flow assist system, blood can be pumped proximally along the primary flow pathway and the secondary flow pathway. The system can include a sleeve bearing distal the impeller. The system can include a drive unit having a distal end disposed distal a proximal end of the second impeller. The drive unit comprising a drive magnet and a drive bearing between the drive magnet and the impeller assembly.

Provided is an electric water pump in which a portion of a fluid discharged from the vicinity of an outer peripheral edge of an impeller flows between the impeller and a lower casing, flows between a rotor and the lower casing, flows between a shaft and the rotor along a channel formed inside the rotor, and then flows to an inlet side of the impeller such that the fluid circulates outside and inside the rotor, and thus, foreign matters contained in the fluid do not accumulate in an accommodation space between the rotor and the lower casing, and thus, efficiency and durability of a motor can be improved.

A magnetic pump comprising: a pump body supporting an output shaft on a wet side of the pump and having an inlet and at least one outlet for pumped fluid; an input drive element on a dry side of the pump, at least one magnet for coupling the input and output shafts such that motion of the input shaft causes motion of the output shaft, a pressure containing structure mounted on the pump body for separating the dry and the wet sides, wherein the pump includes: one or more pathways through which pumped fluid can pass so as to lubricate one or more moving parts within the pressure containing structure, and a monitoring port/channel through which one or more properties of pumped fluid passing through the one or more pathways can be sensed.

A blood flow assist system can include an impeller assembly including an impeller shaft and an impeller on the impeller shaft, a primary flow pathway disposed along an exterior surface of the impeller. The system can include a rotor assembly at a proximal portion of the impeller shaft. A secondary flow pathway can be disposed along a lumen of the impeller shaft. During operation of the blood flow assist system, blood can be pumped proximally along the primary flow pathway and the secondary flow pathway. The system can include a sleeve bearing distal the impeller. The system can include a drive unit having a distal end disposed distal a proximal end of the second impeller. The drive unit comprising a drive magnet and a drive bearing between the drive magnet and the impeller assembly.

A blood flow assist system can include an impeller assembly including an impeller shaft and an impeller on the impeller shaft, a primary flow pathway disposed along an exterior surface of the impeller. The system can include a rotor assembly at a proximal portion of the impeller shaft. A secondary flow pathway can be disposed along a lumen of the impeller shaft. During operation of the blood flow assist system, blood can be pumped proximally along the primary flow pathway and the secondary flow pathway. The system can include a sleeve bearing distal the impeller. The system can include a drive unit having a distal end disposed distal a proximal end of the second impeller. The drive unit comprising a drive magnet and a drive bearing between the drive magnet and the impeller assembly.

A blood flow assist system can include an impeller assembly including an impeller shaft and an impeller on the impeller shaft, a primary flow pathway disposed along an exterior surface of the impeller. The system can include a rotor assembly at a proximal portion of the impeller shaft. A secondary flow pathway can be disposed along a lumen of the impeller shaft. During operation of the blood flow assist system, blood can be pumped proximally along the primary flow pathway and the secondary flow pathway. The system can include a sleeve bearing distal the impeller. The system can include a drive unit having a distal end disposed distal a proximal end of the second impeller. The drive unit comprising a drive magnet and a drive bearing between the drive magnet and the impeller assembly.