Propulsion engine
AssigneeROLLS-ROYCE plc
InventorsDavid Anthony EDWARDS, Richard NICHOLSON
Life of this patent
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Abstract
A propulsion engine for an aircraft, the propulsion engine comprising: one or more fans (1, 2) rotatably linked to one or more respective shafts (11); a driving means arranged to drive the one or more fans; and a first hydraulic pump-motor (10) connected to one of the fan shafts, the first hydraulic pump-motor comprising a cam (12) disposed about the shaft and one or more radially extending pistons (13) arranged to engage a surface of the cam, the cam and pistons being arranged such that the pistons reciprocate due to the rotation of the cam, wherein the first hydraulic pump-motor is arranged to selectively transfer a variable amount of power to or from the one or more fans so as to control the rotational speed of the one or more fans.
Claims20
A propulsion engine for an aircraft, the propulsion engine comprising:
- one or more fans rotatably linked to one or more respective shafts;
- a driving means arranged to drive the one or more fans;
- and
- a first hydraulic pump-motor connected to one of the fan shafts, the first hydraulic pump-motor comprising a cam disposed about the shaft and one or more radially extending pistons arranged to engage a surface of the cam, the cam and pistons being arranged such that the pistons reciprocate due to the rotation of the cam,
- wherein the first hydraulic pump-motor is arranged to selectively transfer a variable amount of power to or from the one or more fans so as to control the rotational speed of the one or more fans.
A speed controlling assembly for a propulsion engine, the propulsion engine comprising one or more fans rotatably linked to one or more respective shafts,
- wherein the speed controlling assembly comprises a first hydraulic pump-motor connectable to one of the fan shafts, the hydraulic pump-motor comprising a cam disposed about the shaft and one or more radially extending pistons arranged to engage a surface of the cam, the cam and pistons being arranged such that the pistons reciprocate due to the rotation of the cam;
- and
- wherein the hydraulic pump-motor is arrangeable to selectively transfer a variable amount of power to or from the one or more fans so as to control the rotational speed of the one or more fans.
A method of controlling a propulsion engine for an aircraft, the propulsion engine comprising one or more fans rotatably linked to one or more respective shafts, wherein the method comprises:
- providing a first hydraulic pump-motor connected to one of the fan shafts, the hydraulic pump-motor comprising a cam disposed about the shaft and one or more radially extending pistons arranged to engage a surface of the cam, the cam and pistons being arranged such that the pistons reciprocate due to the rotation of the cam;
- driving the one or more fans by virtue of a driving means;
- selectively transferring a variable amount of power to or from the one or more fans by virtue of the hydraulic pump-motor;
- and
- controlling the rotational speed of the one or more fans.
Dependencies are inferred from the claim text.