A magnetic bearing contactlessly supporting a rotor by magnetic force includes: a bearing rotor member made of a magnetic material; and a bearing stator member arranged around bearing rotor member. The bearing stator member includes a core made of a magnetic material and a coil wound around the core. A longitudinal cross-sectional shape of the core has a first part extending in a first direction orthogonal to a direction opposed to the bearing rotor member and wound around with the coil, a pair of second parts extending from both end portions in the first direction of first part to the bearing rotor member side and subsequently extending in a direction approaching each other in the first direction, and a pair of third parts extending from respective distal end portions of the pair of second parts toward the bearing rotor member side. The bearing rotor member also includes a permanent magnet.

A rotor bearing system includes an inner bearing component and an outer bearing component. One of the bearing components includes at least three protrusions sized to form a close running proximity to the remaining component. A bearing gap between the inner bearing component and the outer bearing component is sized to exclude the entry of red blood cells between the bearing components during operation of the rotor bearing system and causing the bearing to operate in an elasto-hydrodynamic regime of mixed- or boundary-lubrication.

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.

The present disclosure relates to a stiffness enhancing mechanism for a magnetic suspension bearing, a magnetic suspension bearing including the stiffness enhancing mechanism, and a blood pump. The magnetic suspension bearing comprises a stator with stator teeth and a rotor disposed within the stator. The stiffness enhancing mechanism comprises: a rotor permanent magnet, a stator permanent magnet, and an axial driving body. The rotor permanent magnet and the rotor of the magnetic suspension bearing form a rotor assembly, which has an asymmetric structure with respect to the main plane (P) of the rotor. The stiffness enhancing mechanism is configured such that the stator permanent magnet generates a radial attractive force to the rotor permanent magnet, and the axial driving body generates an axial repulsive force to the rotor permanent magnet, wherein the magnitude of the axial repulsive force is variable with a change of an axial distance between the axial driving body and the rotor permanent magnet). The stiffness enhancing mechanism can increase the torsional stiffness of the rotor of the magnetic suspension bearing and facilitate the miniaturization of the magnetic suspension bearing.

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.

This invention is directed to a corrosion resistant permanent magnet, to a method for producing a corrosion resistant permanent magnet, and to an intravascular blood pump comprising the magnet. The magnet is corrosion resistant due to a composite coating comprising a metal layer, optionally a metal oxide layer, a layer formed from poly(2-chloro-p-xylylene), and a linker layer between the metal oxide layer and the poly(2-chloro-p-xylylene) layer.

Various aspects of the present disclosure are directed toward apparatuses, systems, and methods that may include a magnetic drive system of a blood pump. The magnetic drive system may include a drive shaft coupled to an impeller, a driven magnet assembly coupled to at least one of the drive shaft and the impeller, and a driving coil assembly configured to drive the driven magnet assembly.

A bearing assembly is configured to retain a distal end of an impeller of a blood pump, where the impeller includes a drive shaft. The bearing assembly includes a pivot member coupled to a distal end of the drive shaft; a distal bearing cup having a proximally-facing surface configured to engage at least a portion of a distal section of the pivot member; and a sleeve bearing disposed around at least a portion of a proximal section of the pivot member.