A system having a variable diameter impeller device that is operable for reducing an energy consumption of a rotating fluid or gas pump by increasing the impeller diameter as a speed of the rotating fluid or gas pump increases and decreasing the impeller diameter as the speed decreases. An extendable vane arrangement is configured to move along an elongated curved or sloping slot, the movement along the elongated curved or sloping slot is operable for increasing and decreasing a diameter of the impeller device. A spring arrangement having a first end and a second end extends and retracts to dynamically increase or decrease a diameter of the impeller device.

A bistable pitch propeller includes a ball, a spring, and a clutch module where the clutch module has a range of rotational movement between a locked end position and a released end position. The clutch module includes a detent, where the ball sits inside and outside of the detent when the clutch module is in the locked end position and released end position, respectively. In response to an input torque and a spring force from the spring, the clutch module rotates toward the released end position and the locked end position, respectively. The bistable pitch propeller also includes an aircraft blade where the aircraft blade is at the first pitch angle and the second pitch angle when the clutch module is in the locked end position and the released end position, respectively.

The invention relates to a compressible and expandable blade (2) for the rotor of a fluid pump (30) having at least two lamellae (3, 4, 5) which are disposed adjacently, are pivo table respectively relative to an axis of rotation (Ia) of the rotor and moveable relative to each other, and abut against each other in the expanded state of the blade such that they form together a continuous blade surface.

The invention relates to a compressible and expandable blade for the rotor of a fluid pump having at least two lamellae which are disposed adjacently, are pivotable respectively relative to an axis of rotation of the rotor and moveable relative to each other, and abut against each other in the expanded state of the blade such that they form together a continuous blade surface.

A flexible guide vane structure of a mixed flow pump with adjustable flow area, a mixed flow pump and an adjustment method are provided. The flexible guide vane structure includes a flexible guide vane and a flexible guide vane adjusting device. The flexible guide vane adjusting device includes a support rib, a support rib base and a base driving mechanism. As the skeleton of the flexible guide vane, the support rib realizes the shape change of the flexible vane through the base driving mechanism and the support rib base. In the mixed flow pump, the flexible guide vane adjusting device is installed inside the blade hub. Through the flow section feedback regulation system, the angle of the support rib is adjusted based on the real-time working condition of the mixed flow pump to adjust the flow area of the blade and achieve the best working condition.

The invention concerns a hydraulic adjusting device (1, 35) having at least two leakage paths (24, 25) which are connected by a transition channel (27), a sealing arrangement (18) which leads back to a working chamber (10) being provided in one of the leakage paths (24, 25) in delimiting manner relative to the working chamber (10) of the adjusting device (35).

A system having a variable diameter impeller device that is operable for reducing an energy consumption of a rotating fluid or gas pump by increasing said impeller diameter as a speed of said rotating fluid or gas pump increases and decreasing the impeller diameter as the speed decreases. An extendable vane mechanism is configured to move along an elongated curved or sloping slot, said movement along the elongated curved or sloping slot is operable for increasing and decreasing a diameter of the impeller device. A spring mechanism having a first end and a second end extends and retracts to dynamically increase or decrease a diameter of the impeller device.

The invention relates to a compressible and expandable blade (2) for the rotor of a fluid pump (30) having at least two lamellae (3, 4, 5) which are disposed adjacently, are pivo table respectively relative to an axis of rotation (Ia) of the rotor and moveable relative to each other, and abut against each other in the expanded state of the blade such that they form together a continuous blade surface.

A method for optimizing the blade axis position of a water pump under all operating conditions which includes determination of multiple calculation conditions within the range of all the operating conditions of the water pump, three-dimensional modeling and mesh generation of the calculation area of the flow field of the water pump at multiple blade angles, numerical simulation of the flow field and calculation and determination of blade hydraulic torques under multiple conditions, determination of the range of the position of the blade resultant hydraulic pressure action line and an optimal blade axis position under all the operating conditions, determination of the small region of the optimal blade axis position under all the operating conditions, determination of the optimal blade axis position, and comparison of the blade hydraulic torques before and after optimization of the blade axis position.

The invention relates to a control apparatus for a hydraulic variable-pitch propeller (12) of an aircraft, land vehicle or water vehicle, comprising: a hydraulic oil feed line (24); a control line (16) which can be connected to the variable-pitch propeller (12); a pressure generating device (73) which is connected to the hydraulic oil feed line (24) and provides hydraulic oil with a basic pressure; a servo valve (78) which is arranged downstream of the pressure generating device (73), the input pressure to which servo valve is the basic pressure and the output pressure from which servo valve during normal operation defines a control pressure in the control line (16) and which servo valve is connected to a controller (28) which delivers a control signal for changing the control pressure; and pressure reducing means which are arranged downstream of the servo valve (78) and upstream of the control line (16), which are mechanically actuated and which, in the event of a failure of the servo valve (78), change the control pressure in the control line (16).