A hydraulic pump includes a casing, an impellor pump comprising a rotor that is rotationally mobile with respect to the casing about a first axis, the rotor comprising several blades in helix form, a transition zone belonging to the casing and having, on the side of the impellor pump, a ramp in helix form developing in the same direction as the helix form of the blades, a trochoid pump comprising a rotor with outer toothing secured to the rotor of the impellor pump, and a rotor with internal toothing that is rotationally mobile with respect to the casing about a second axis parallel to and offset from the first axis, the trochoid pump being fed by the impellor pump through the transition zone running along the ramp.

The invention provides a fluid pump apparatus comprising a fluid inlet, a fluid outlet, a screw member and a rotatable pump member. The screw member has at least one helical screw blade configured to be rotated by a fluid flow stream and the rotatable pump member is in fluid communication with the fluid inlet and/or fluid outlet.

To design the rotor (6, 6′, 6″, 6″′, 60, 60′) as compressible in the radial direction in a fluid pump, in particular for microinvasive medical use, said rotor is configured as stretchable in its longitudinal direction (16) by push elements and pull elements acting axially on it.

To design the rotor (6, 6′, 6″, 6″′, 60, 60′) as compressible in the radial direction in a fluid pump, in particular for microinvasive medical use, said rotor is configured as stretchable in its longitudinal direction (16) by push elements and pull elements acting axially on it.

A ship screw, pump screw or turbine screw for use under water or another liquid, comprising a front side and a rear side, wherein water or another liquid is forced from the front side to the rear side in use, and comprising a hub and at least two blades extending from said hub, wherein the blades are substantially helical/spiral shaped, their effective surface area increasing from the front side toward the rear side.

Apparatus comprising and methods are described including a blood pump that includes an axial shaft, and an impeller disposed on the axial shaft. The impeller is configured to pump blood of the subject by rotating. The impeller and the axial shaft are configured to undergo axial back-and-forth motion during operation of the impeller. A distal tip element is disposed at a distal end of the blood pump. The distal tip element defines an axial-shaft-receiving tube, configured to receive at least a portion of the axial shaft during forward motion of the axial shaft. The distal tip element additionally defines an atraumatic distal tip portion disposed distally of the axial-shaft-receiving tube. Other applications are also described.

Apparatus comprising and methods are described including a blood pump that includes an axial shaft, and an impeller disposed on the axial shaft. The impeller is configured to pump blood of the subject by rotating. The impeller and the axial shaft are configured to undergo axial back-and-forth motion during operation of the impeller. A distal tip element is disposed at a distal end of the blood pump. The distal tip element defines an axial-shaft-receiving tube, configured to receive at least a portion of the axial shaft during forward motion of the axial shaft. The distal tip element additionally defines an atraumatic distal tip portion disposed distally of the axial-shaft-receiving tube. Other applications are also described.

A cylindrical rotor inside of the cylindrical stator, wherein the cylindrical rotor has a screw thread with an opposite direction relating to the stator screw thread, wherein the rotor has a curvilinear external surface shape and a stator having an internal semicircular surface shape wherein rotor external surface shape and the stator has an internal surface shape having rounded shapes without rectangular edges to obtain high speed performance with reduced vortices, wherein a gap between the internal surface of the stator and the external surface of the rotor is 0.1-0.2 millimeters and an unloading thrust bearing attached to the rotor shaft positioned between intake thrust bearing and the intake end of the rotor and a cavity in the unloading thrust bearing configured to receive production fluid from the discharge end of the rotor.

An apparatus including an array of coils wherein each coil of the array of coils is wound around a core region for containing a fluid; an external magnet assembly mounted outside of the array of coils and movable over the array of coils; and an internal magnet assembly mounted inside the core region around which the coils of the array of coils are wound, wherein the internal magnet assembly is aligned with and magnetically coupled to the external magnet assembly so that the external and internal magnet assemblies move together along the array of coils in response drive signals applied to the coils within the array of coils.

An impeller includes a hub, and a plurality of blades supported by the hub, the blades being arranged in at least two blade rows. The impeller has a deployed configuration in which the blades extend away from the hub, and a stored configuration in which at least one of the blades is radially compressed, for example by folding the blade towards the hub. The impeller may also have an operational configuration in which at least some of the blades are deformed from the deployed configuration upon rotation of the impeller when in the deployed configuration. The outer edge of one or more blades may have a winglet, and the base of the blades may have an associated indentation to facilitate folding of the blades.