Abstract: A pitch bearing is described for connecting a blade of a wind turbine to a hub of the wind turbine to allow a rotation of the blade about a longitudinal axis, which pitch bearing includes a console housing arranged at a conjunction of the hub and an end section of the blade, which console housing encloses a plurality of planar sliding surfaces arranged around an opening in the hub. Further described is a wind turbine including at least one blade attached to a hub via such pitch bearing. A method of performing maintenance on a pitch bearing is described where a part of the pitch bearing is removed while leaving the blade and the remaining parts of the pitch bearing in place; and the part is replaced after a maintenance step has been carried out.

Abstract: A rotor for a turbomachine includes at least one moving blade row including a plurality of moving blades disposed adjacent to one another in a circumferential direction with respect to an axis of rotation. Each one of the plurality of moving blades includes a blade leaf and a blade root having an outer face, the outer face of the blade root including a blade root curved end wall contour adjacent the blade leaf in the circumferential direction. The blade root curved end wall contour has a concave curvature in an axial sectional plane of the rotor. At least one rotor shaft includes a reception slot for a respective one of the at least one moving blade row extending in the circumferential direction. Each of the plurality of moving blades is inserted into the reception slot via a respective blade root.

Abstract: The present invention relates to a blade for a wind power plant with an assembly face for mounting in a circular pitch bearing, whose pitch axis is angled relative to the longitudinal axis of the blade, and wherein the blade comprises a root part with an approximately elliptic cross-section, in which root part the assembly face is arranged. The invention further relates to a wind power plant in general having a pitch-adjustable blade mounted in a pitch bearing such that the distance between the outermost part of the blade and the tower is increased when the leading edge of the blade is pitched up in the wind. This is accomplished in that the longitudinal axis of the blade is angled in a particular way compared to its pitch axis.

Abstract: The invention relates to a fluid pump comprising at least one impeller blade (1, 1?, 1?) which is rotatable about an axis of rotation (3) and conveys a fluid in operation and comprising a support device (4, 6, 7, 8, 9, 10, 12, 12?, 13, 13?, 14, 14?, 15, 17) which supports the at least one impeller blade (1, 1?, 1?)in at least one support region, wherein the support device is changeable between a first state in which the rotor is radially compressed and a second state in which the rotor is radially expanded; and wherein at least one impeller blade extends at least partly radially inwardly with respect to the axis of rotation (3) from the support region/support regions in the radially expanded state of the rotor.

Abstract: A rotor blade coupling device (9) comprising a torsionally rigid carrier (4) is disclosed, the carrier (4) being mounted in a manner which is free of centrifugal force between a thrust bearing (3) and a control bearing (5), resilient impact and pivoting movements of the rotor blade coupling device (9) being able to take place in a damped manner. The rotor blade coupling device (9) is clamped between a rotor head star (101) and a rotor head central piece (102) and held rotatably about the rotor axis A. The centrifugal forces which occur, are transmitted from a rotor blade holder (2) to the rotor head star (101) and thus kept away from the carrier (4).

Abstract: A system for varying an angle of attack of blades of an aircraft turbine engine propeller, including an axial flow brushless motor including a stator including coils, and a rotor including permanent magnets. The rotor is mounted axially movable between a locked position in which it is secured in rotation with a rotary hub of the propeller, and an unlocked position in which its rotation relative to the hub along the axis of rotation of the propeller causes a variation of the angle of attack of the blades via a mechanical connecting mechanism.

Abstract: Described is a fan with a blade suitable for use as a ceiling fan. The blade may be regarded as a single blade, although shaft is not attached to blade at one end thereof; rather, shaft is attached to blade at a point between first end and second end. Blade is balanced by counterweights located in blade. In one embodiment, blade is connected to shaft by means that permit angular movement, such as a teeter hinge.

Abstract: The invention refers to a wind generator of electrical current production with a vertical axle and inhibition over-speed laps. the wind generator is setted on a steady duct on the upper place of which there is a thrust bearing. There are three (internal) laps mounted on the generator and under the thrust bearing. These flaps are totally the same. They are setted in 120 degrees corner among them. Three other laps (external) are fixed on these flaps. The external flaps are constructed with aerodynamic cross section. These laps have special ribs and housings for edge support while a wire rope mounted to the internal of the laps prevents the spreading in case of fracture. According to the invention we have internal and external flaps. Because of the rotation speed increasement the external flaps gradually change place so the incidence angle of the wind changes and the flaps resist to the wind flow keeping the rotation speed steady.

Abstract: There is provided a wind turbine generator that includes an improved grease supply and discharge system of lubricant oil used in a blade rotating ring bearing of a wind turbine blade, and can reliably recover discharged grease. The wind turbine generator includes a pitch control mechanism that can adjust a pitch angle of the wind turbine blade via the blade rotating ring bearing provided between the wind turbine blade and a rotor head, a grease supply and discharge device is provided in the rotor head, and the grease supply and discharge device includes a grease supply device that pumps lubricant oil in a supplied grease tank with a grease supply pump and supplies the lubricant oil to the blade rotating ring bearing, and a grease discharge device that forcibly sucks and recovers the discharged grease from the blade rotating ring bearing.

Abstract: A hub-profile connection system for axial fan is disclosed, consisting of a hub to which one or more blades provided with an air displacement profile are connected, wherein one or more blades are attached in a flexible manner to the hub by means of two separate flexible elements, both fixed, reciprocally distinct, separate and overlapped one to the other in the fan axis direction on the hub side, to a fastening block and, on the blade side, to a corresponding fastening block. Compared with the known rigid, hinged and flexible constraint systems, the system of the present invention offers lower static and dynamic loads, as well as construction simplicity, with consequent cost saving and vibration abatement.

Abstract: A variable vane assembly for a gas turbine engine is disclosed herein. The variable vane assembly includes a vane operable to pivot about a pivot axis. The vane includes a flap portion positionable in a fluid stream for controlling a flow of fluid. The vane also includes a stem portion for mounting the flap portion. The vane also includes a button portion positioned between the flap portion and the stem portion along the pivot axis. The button portion is wider than the stem portion in at least one plane containing the pivot axis. The variable vane assembly also includes a bushing encircling the stem portion and abutting the button portion. The variable vane assembly also includes a labyrinth seal positioned between the bushing and the button portion.

Abstract: An attachment stud for a variable vane assembly is disclosed. The attachment stud may generally include a bottom segment, a middle segment, a top segment and a shoulder segment. The bottom segment may generally have a shape and configuration adapted to be secured to a synchronizing ring of the variable vane assembly. The middle segment may generally have a shape and configuration adapted to receive a rotational attachment device of the variable vane assembly. The shoulder segment may be disposed between the bottom segment and the middle segment. The top segment may generally have a shape and configuration adapted to receive a retaining device configured to rigidly attach the rotational attachment device to the attachment stud.

Abstract: A wind turbine (20) includes a turbine wheel (22). Radially extending sailwing assemblies (30) are supported between the axle structure (28) and the perimeter rail (26) of the turbine wheel. The sailwing assemblies include sail end supports (52, 53), sail support cables (54, 55) extending between the sail end supports, and sailwings (58) that are supported by the sail support cables and extend between the axle structure (28) and the perimeter rail (26) of the turbine wheel. The sail end supports (52, 53) may be pivoted to form a pitch in the sailwings (58) and pivoted with respect to each other to form a twist in the sailwings, and sail spreader bars (70) may be mounted in the sailwings and connected to the sail support cables (54, 55) to adjust the effective width and loft of the sailwings.

Abstract: A wind turbine includes a rotor having a rotational axis and a wind turbine blade connected to a hub through a pitch bearing. The pitch bearing includes an outer ring, a center ring and an inner ring. The pitch bearing further includes a first rolling element arrangement having at least two rows of rolling elements between the center ring and one of the inner and outer rings, and a second rolling element arrangement having at least one row of rolling elements between the center ring and the other of the inner and outer rings. A first row of the at least two rows is arranged at a first distance from the rotational axis, and a second row of the at least two rows is arranged at a second distance from the rotational axis greater than the first distance. A pitch bearing for a wind turbine is also disclosed.

Abstract: An improved rotor blade used in combination with a submersible electrical generator comprises a rotor base with width BW, a leading edge, a tip, and a trailing edge. The leading edge and the trailing edge are defined as elliptical curves having a radius of 8.0 BW. The rotor has a surface area profile substantially in accordance with the Cartesian coordinate values X and Y set forth in Table I. The rotor blade can be functionally connected to a rotor shaft through a pivotal support axial which allows the pitch of the blade to be set and maintained. The pitch is set to harness the kinetic energy of flowing water for generating electricity.

Abstract: The present invention relates to a blade made of composite, comprising a vane formed of woven filaments impregnated with a thermosetting resin with a protective element in the region of the leading edge of the vane comprising a part in the form of a rigid strip, said strip being secured to the vane. The blade is characterized in that at least one layer of a viscoelastic material is at least partially interposed between said rigid strip and the vane so as to form, with the protective element, a means of damping the vibrations of the vane.

Abstract: The invention relates to a propeller blade bearing, for the propeller blades of aircraft propellers that can be adjusted along their longitudinal axis, a plurality of propeller blades being individually fastened on a propeller hub in a corresponding number of blade seats. Every propeller blade, at its blade base, has a primary adjustable bearing and a secondary adjustable bearing and is received so as to be rotatable along its longitudinal axis inside a blade seat. The primary and the secondary adjustable bearing are configured as angular contact ball bearings that have respective upper bearing races and lower bearing races and rolling bodies interposed between said bearing races. A lubricating oil reservoir is arranged in the propeller hub and supplies the primary and the secondary adjustable bearing with lubricating oil when the propeller rotates. Every propeller blade is configured as a completely pre-assembled unit with the primary adjusting bearing and the secondary adjusting bearing.

Abstract: The vertical windmill includes a rotatable wind wheel column mounted to a base. The column includes a plurality of hollow wheel hubs stacked vertically atop each other. Each wheel hub includes a plurality of radiating mounting arms equidistantly spaced around the axis of the wheel hub such that the arms of an adjacent hub are angularly offset with respect to the other. A plurality of mounting assemblies is disposed on each of the mounting arms for mounting an array of wing blades. Each alternate stacked wheel hub and mounting arms together forms a wind wheel with vertically oriented wing blades mounted between upper and lower spaced arms such that the top wheel is interconnected with the lower wheel at a height less than the height of the blades. Each array of blades may freely rotate or be positively rotated to orient the blades for optimum usage of wind power in rotating the column.

Abstract: A cooling fan (20) includes a housing (22) and an impeller (24). The housing has a base (221), a sidewall (222) extending from a periphery of the base with an air outlet (226) defined therein, and a cap (223) covering the sidewall. The impeller has a plurality of blades (242) rotatably received in the housing for generating an airflow. An air channel (225) is formed between tip portions of the blades and an inner face of the sidewall. The air outlet has a near section (226A) and a far section (226C). The airflow first reaches the near section and then the far section. The base of the housing has a protrusion (227) extending into the air outlet for guiding the airflow flowing towards the far section from the near section of the air outlet.

Abstract: A propeller blade assembly (1) comprises a plurality of propeller blades (10) each connected to a hub (2) via at least one bearing assembly (3,4). Each of the blades (10) and the bearing assemblies (3,4) is preloaded, wherein the preload is applied over a preload path which includes a blade root portion (11) of each blade (10) and the bearing assemblies (3,4), and a spring (6) is provided in the preload path. In the event of wear of the components of the propeller blade assembly, the spring (6) maintains the preload force. A method of applying the preload to the propeller blade assembly (1) is also disclosed.

Abstract: A wind turbine rotor having variable blade pitch is provided. According to one embodiment, the wind turbine rotor includes a hub defining a predetermined number of openings, the hub further including a rotatable adjustment layer defining a predetermined number of slots, wherein the slots corresponds to the openings; and one or more blades secured in the hub, each of the one or more blades including a blade root, and a protrusion extending from the blade root, and wherein the protrusion of each of the one or more blades is engaged by a corresponding slot of the adjustment layer, wherein rotation of the adjustment layer translates the protrusions of each of the one or more blades, thereby rotating each of the one or more blades about the longitudinal axis. The rotor may be removably secured to a generator shaft by a spring, allowing easy adjustment of the rotor for educational use.

Abstract: This blade attachment device comprises a shell (28) installed around an outer collar (23) of the pivot (15) of the blade (27) and capable of rotating by an angle sufficient for cleats (30, 31) to close the ends of the pivot groove and retain the root of the blade (27) in it, and mobile shims that cooperate to retain the root in the groove.

Abstract: The invention concerns a Wells turbine, comprising a hub with a plurality of rotor blades having a drop-shaped profile orienting from a profile nose; the rotor blades are attached to the hub in a rotary fashion by means of a foot part such that the rotor blade angle is variable with respect to the plane of rotation, wherein the associated rotational axis intersects the chord for each profile section in a threading point, which is located in a region between the profile nose and the aerodynamic center of the profile; the adjustment of the blade angle is made passively by the equilibrium occurring during the operation of the wells turbine between the aerodynamic torque, acting on the rotor blades, and the centrifugal torque, wherein the average density of the rotor blade is selected to be less than 2700 kg/m3 and/or the mass distribution within the profile is selected such that the surface centrifugal torque of the rotor blade is reduced relative to a profile made from a solid and/or the surface centrifugal tor

Abstract: A system for controlling pitch of a propeller blade of a turboshank engine, including two automatic locking members making it possible, depending on their controlled position, to lock rotation of a blade root in both directions of rotation, or to allow the rotation of the blade root support in either of the two directions.

Abstract: A ceiling fan (50) is disclosed having a motor housing (51) which encases an electric motor (53). The motor includes a bottom mounting plate (54) that rotates and thereby drives an annular array of blade irons (56), each having a blade (57) mounted thereto in conventional fashion. Each blade iron is mounted for pivotal and radial movement relative to the bottom mounting plate. An annular segmented balancing ring (68) made of a plurality of links (69) causes pivotal and radial movement of other blade irons (76) in response to the radial movement of an off-balanced blade iron.

Abstract: The invention relates to a fan, particularly a radial fan, having a fan hub with a rotational axis. A plurality of fan blades is disposed about the rotational axis for deflecting an air flow. The invention provides that an adjustment device is provided at the fan blades for the rotational speed-dependant adjustment of an air flow.

Abstract: A stator blade and a stator blade arrangement for a turbomachine which is exposable to axial throughflow is provided. Each stator blade is retained via a fixed clamping in a circumferential groove. For the fixed clamping, provision is made on one side of the blade root for a shaped piece with a threaded hole into which a tensioning screw, which is supported on the bottom of the circumferential groove, may be screwed.

Abstract: Quick attachable and detachable mounting arms for ceiling fans. A first version has flat headed fasteners initially attached to one end of mounting arms, with key-hole slots in the endshield of the ceiling fan motor. The user raises the mounting arm so that the flat headed fasteners fits through the larger openings in the keyhole slots and then pulls the mounting arm outward until the arm locks in place by the smaller opening portions of the keyhole slots. Rubber type gaskets and washers help lock and hold the mounting arms in place. The flat headed fasteners can also be located on the endshields with the keyhole slots on mounting arms. A second embodiment includes inwardly deformable springably snapable fasteners that can be located on the ends of the mounting arms which can deform inwardly and expand after passing through slots on the endshield of the rotor. Alternatively, the fasteners can be located on the bottom of the endshield with the receiving slots on the ends of the mounting arms.

Abstract: A wind energy plant with a rotor hub housing, which is connectable to at least one pitch bearing via joining means, and with at least one rotor blade, the blade root of which is connected to the pitch bearing, wherein a stiffening element is provided, which is fastened between the pitch bearing and the rotor hub housing.

Abstract: A rotary coupling having a first element and a coaxial second element, the first and second elements being rotatable relative to each other and defining an annular passage between radially facing walls thereof. The coupling has a sealing ring at an end of the annular passage, the sealing ring being mounted to the wall of the first element and rotating relative to the second element, and having an active configuration in which the sealing ring is urged against the wall of the second element to seal the end of the annular passage, and a return configuration in which the sealing ring does not seal the end of the annular passage. A control system is used to apply a variable load to the sealing ring, wherein the sealing ring moves between the active and return configurations in response to variation in the applied load.

Abstract: The invention relates to a wind turbine rotor comprising at least one blade and at least on pitch mechanism comprising a ring shaped motor for controlling the blade. The wind turbine rotor is characterized in that, the ring shaped motor controls the blade through gearing means of a planetary type. The invention further relates to a rotation controlling mechanism comprising, at least one ring shaped motor for controlling the rotation of at least one first part in relation to at least one second part. The rotation controlling mechanism is characterized in that, the ring shaped motor controls the relative rotation through gearing means of a planetary type. Even further the invention relates to a method for controlling at least one blade of a wind turbine rotor.

Abstract: A propeller blade mounted with a preload adjacent a propeller blade root retention which increases the moment capacity of the retention for a given pitch diameter, yet permits pitching of the propeller blade about a blade axis in response to a propeller pitch change actuation system. The propeller blade retention assembly includes a tapered roller bearing set having a multiple of tapered roller bearing cartridge assemblies. Each tapered roller bearing cartridge assembly includes a retention cartridge and at least one tapered roller bearing element to facilitate installation and retention during assembly.

Abstract: An aerodynamic brake assembly for use with an airfoil such as the blade of a wind turbine rotor comprises deployable upper and/or lower spoiler plates incorporated in or attached to the airfoil. The spoiler plates can deploy under the influence of centrifugal forces when the rotating airfoil or rotor blade reaches a pre-determined rotational speed. The aerodynamic brake assembly may be integrated within the airfoil or attached to the tip of the airfoil such that, when not deployed, the upper and lower spoiler plates have a profile that approximately conforms to the profile of the part of the airfoil to which it the brake assembly is attached. Thus in a non-deployed state, the spoiler plates have a non-detrimental effect on the performance of the airfoil, and may even contribute to its aerodynamic lift properties.

Abstract: A wind turbine that is mounted on a corner of a building and has a shaft that extends upward and outward from the corner, where the turbine blades are located, and the resulting rotation of the shaft is used for some power consumption purpose in our outside the building.

Abstract: A fan assembly for creating an air current includes an air outlet mounted on a stand. The stand includes a base and a body tiltable relative to the base. The fan assembly has a centre of gravity located so that when the base is located on a substantially horizontal support surface, the projection of the centre of gravity on the support surface is within the footprint of the base when the body is in a fully tilted position.

Abstract: A multiple rotor wind turbine, having variable angular and/or axial displacements between the two or more rotors. The variation in angle and axial displacement between the rotors (and the corresponding turbine blades affixed to said rotors) control the torque characteristics of the turbine at varying wind speeds.

Abstract: The invention relates to an axial fan comprising a boss and a number of blades evenly distributed and arranged to the boss, wherein the blades have an aerofoil profile, each blade is arranged to the boss with a strip, wherein each blade is hollow and the strip is at least partially inserted into the blade, and that at least one fastener runs from the surface of the blade through a corresponding opening in the strip to the opposite surface of the blade, wherein the corresponding opening in the strip is a slot, such that the pitch of the blade is adjustable, by rotation of the blade relative to the strip along the axial axis of the blade.

Abstract: An improved rotor blade used in combination with a submersible electrical generator comprises a rotor base with width W, a leading edge, a tip, and a trailing edge. The leading edge and the trailing edge are defined as elliptical curves having a radius of 8.0(W). A straight line drawn from the front of the base to the lip forms a forty five degree angle with respect to the rotor base. The rotor blade is functionally connected to a rotor shaft through a pivotal support axial which allows the pitch of the blade to be set and maintained. The pitch is set to harness the kinetic energy of flowing water thereby generating electricity.

Abstract: A ceiling fan (10) is disclosed having a motor housing (11) which encases an electric motor (13). The motor includes a bottom mounting plate (14) that rotates and thereby drives an annular array of blade irons (16), each having a blade (17) mounted thereto in conventional fashion. Each blade iron is mounted for pivotal and radial movement relative to the bottom mounting plate. An annular balancing ring (28) causes pivotal and radial movement of other blade irons (36)in response to the radial movement of an off-balanced blade iron (35).

Abstract: A fan (10) is disclosed having an electric motor (13) which rotatably drives an annular array of blade irons (14) each having a blade (15) mounted thereto. Each blade iron has a motor mounting portion (21) configured to be coupled with the electric motor for rotation. The motor mounting portion has an arcuate, vertical wall (26) and a horizontal flange (27). The horizontal flange has a first mounting hole (28) and an oblong second mounting hole (29). A first mounting screw (31) having a first bushing or bearing (32) thereon passes through each first mounting hole and into a threaded mounting hole (34) in the motor (13). Similarly a second mounting screw (35) having a second bushing or bearing (36) thereon passes through each second mounting hole and into a threaded mounting hole (37) in the motor. With this configuration the blade iron can pivot relative to the motor.

Abstract: A butt connection of divided hollow profile members, which is suitable in particular for rotor blades of wind power installations, comprises a multiplicity of straps which are arranged along the joint and which bridge over same and which are respectively fixed with their ends to one of the profile members to be connected. In this respect the arrangement is preferably such that one of the two bolts fixing the strap at the ends thereof has a wedge-shaped flattening, by means of which a tensile prestressing can be imparted to the strap.

Abstract: Turboprop and propfan engines generally incorporate blades which have variable pitch to improve operational efficiency. Variable pitch is achieved through a pitch control mechanism at the root of the blade but such mechanisms may fail resulting in the blades turning to define a flat configuration with low drag and therefore the potential for engine damage through over-speeding. Traditional pitch lock and counter weight control mechanisms have disadvantages. By providing a helical bearing in which the mass and radial movement due to centrifugal radial force are utilised it is possible to generate a counter moment to the normal centrifugal turning moment (CTM) to ensure the blade remains in a configuration with at least some drag to limit engine rotational speed. The continuous helical bearing allows for a range of pitch angular positions to be used around a full 360° turn by providing a feathering counter moment from any of those angular positions.

Abstract: A propeller blade mounted with a preload adjacent a propeller blade root retention which increases the moment capacity of the retention for a given pitch diameter, yet permits pitching of the propeller blade about a blade axis in response to a propeller pitch change actuation system. The propeller blade retention assembly includes a tapered roller bearing set having a multiple of tapered roller bearing cartridge assemblies. Each tapered roller bearing cartridge assembly includes a retention cartridge and at least one tapered roller bearing element to facilitate installation and retention during assembly.

Abstract: A propeller blade mounted with a preload adjacent a propeller blade root retention that increases the moment capacity of the retention for a given pitch diameter, yet permits pitching of the propeller blade about a blade axis in response to a propeller pitch change actuation system. During assembly, the preload condition is established by preload springs which apply a load on the end of a tapered roller bearing set as a floating race is rotated which allows the tapered roller bearing set to progressively push the propeller blade root outboard and the floating race inboard to generate the preloaded condition.

Abstract: A wind energy plant with a rotor hub which is connected to at least one pitch bearing, and with at least one rotor blade, the blade root of which is connectable to the pitch bearing via joining means, wherein a stiffening element is provided, which is arranged between the rotor blade root and the pitch bearing and connected to the same via the joining means.

Abstract: Vertical axis turbine apparatus is described in which a rotating blade turbine member mounted on a fixed base consists of one to fifty, preferably two or three, upwardly and outwardly inclined spars (F). On each spar is set at least one aerofoil or hydrofoil section blade (S). If there is more than one spar, the spars are preferably held to one another via a plurality of guy wires (T).

Abstract: This invention relates to an impeller device for data acquisition in a flow. It comprises a support (3) with two bearing blocks (4.1, 4.2) to hold a spindle (2) around which the impeller (1) is fitted. The spindle (2) comprises two approximately conical ends (5). The bearing blocks (4.1, 4.2) are made from a material with the lowest possible coefficient of friction and each comprises an approximately conical recess (6) into which one of the ends (5) of the spindle (2) fit.

Abstract: A pivot assembly that can be used with various appliances. The pivot assembly provides up to three degrees of freedom when positioning the appliance. The pivot may be used, for example, with a fan that is mounted on a base such that direction of the airflow generated can be adjusted about three coordinate axes by manipulating a single rotatable pivot mount. The fan assembly includes a base unit and an arm to which an appliance may be detachably coupled. The opposite end of the arm is provided with a spherical cap which is received by the base unit. Any adjustments to the positioning of the rotatable pivot mount are maintained by the friction within the rotatable pivot mount. Additionally, the pivot mount may include a pivot guide to restrict the degree of rotation about the pivot, thereby increasing stability.

Abstract: The invention concerns a washing fluid pump (1) for windows and/or headlamp cleaning installations on motor vehicles including at least one motor, at least one pump housing (2) with at least one impeller (11) arranged therein, at least one intake (8) and at least two selectively actuable outlets (7). The washing fluid pump (1) is distinguished in that the pump housing (2) includes at least two pump chamber regions which are arranged in mutually superposed relationship, that at least two outlets (7) are associated with different pump chamber regions, and the impeller (11) is axially displaceably supported in the pump housing (2) in such a way that it can assume its operative position selectively in one pump chamber region or the other.

Abstract: This device for mounting a propeller blade in a hub, of the type in which a blade base is mounted in rotation in a hub housing by means of at least two bearings and where a preloading device permitting axially preloading the two bearings comprises a holding ring mounted between one of the two bearings and hub so as to allow an axial displacement of ring relative to hub, in that holding ring is mounted rotatingly between bearing and hub by means of rolling elements and helical tracks arranged to drive an axial displacement of ring during rotation of this ring, means being provided to cause ring to rotate according to a predefined law.