Rolls-royce Corporation

Stephen Granville Garner

Marko Bacic

Jonathan E Holt

Arthur Laurence Rowe

David Michael Gainford

Mark J E Bellis

Michael A Horswill

Joseph H Walker

Mark John Edwin Bellis

John R W Whitmarsh

Jonathan Edmund Holt

Joseph Henry Walker

John Robert William Whitmarsh

A method of detecting shaft break in a gas turbine engine having a shaft system. The shaft system including a shaft that couples a compressor and a turbine. First construct a frequency model of the shaft system. Then determine a notch frequency and a first torsional frequency for the shaft system from the model. Then in real time measure a rotational speed of the shaft; detect the presence or absence of a feature at least one of the notch frequency and the first torsional frequency in the measured speed; and generate a shaft break signal in response to the absence of at least one of the features.

Method of detecting shaft break

An apparatus, for example for a pitch change mechanism, includes a cylinder having a magnetic portion defining an annular array of features extending parallel to the longitudinal axis of the cylinder, the cylinder rotating in use and able to translate longitudinally. There is a sensing arrangement including a stationary magnetised core and two coils connected in series and wound around the core. In use, the cylinder rotates and current is induced in the coils. Monitoring equipment is arranged to calculate rotational speed of the cylinder from the frequency of the current and to calculate longitudinal position from the relative amplitude of the current in each coil. Also a method.

Axial displacement and rotational speed monitoring

A gas turbine engine has a signal transmission system comprising a waveguidewhich enables the transmission of microwave radio signals between a rotorand stationary receiving electronicsof the engine. The waveguideis centered on the engine axis

Gas turbine engine

A shaft break detection system and a method of detecting shaft break for a gas turbine engine. A first indication is calculated from measured rotational speed of a shaft. A second indication is calculated from the rotational speed. A shaft break signal is generated if both indications are true.

Shaft break detection

A system is provided for transmitting data between a first component and a second component, which rotates relative to the first component. The system includes a first coupling element of limited angular extent mounted to the first component, and a second coupling element of limited angular extent mounted to the second component. The first and second coupling elements come into angular alignment once per revolution of the second component relative to the first component. The system further includes a first transceiver connected to the first coupling element, and a second transceiver connected to the second coupling element. The first and second transceivers are configured to detect the angular alignment of the first and second coupling elements. The first and second transceivers are further configured to transmit data between the first and second transceivers via the first and second coupling elements when the angular alignment is detected.

Data transmission system

A method of controlling blade pitch angle, including comparing demanded and measured blade pitch angle and calculating any difference therebetween, in a primary electrical control system, where there is a difference, applying torque to a blade pitch regulator to reduce the magnitude of the difference to zero, and in a secondary electrical control system, where the difference is greater than a pre-determined threshold, applying torque to a blade pitch regulator to reduce the magnitude of the difference to the threshold. Also an electrical system of blade pitch angle control for a set of blades including primary and secondary electrical control systems, means for comparing demanded and measured blade pitch angle and calculating any difference therebetween, a look-up function having the difference as its input and outputting a required torque, and a torque regulator to apply the required torque to the set of blades.

Blade pitch control

A control apparatusfor a gas turbine engine for an aircraft includes engine control meansforming part of an outer fuel control loop and fuel control means/overthrust protectorforming part of an inner fuel control loop. Overthrust protection is provided within each of the engine control meansand the fuel control means/overthrust protector, which are powered and housed separately. Thus, a failure within one of these systems could not result in overthrust and demonstrably reliable overthrust protection is provided within a single channel.

Control system for aircraft engine

An overthrust protection system for a gas turbine in which fuel is supplied at a controlled flow rate to a combustor ( ) of the gas turbine. The overthrust protection system uses a bypass valve ( ) to divert fuel flow away from the combustor ( ). The opening of this valve is controlled by an overthrust controller ( ) to divert fuel flow in response to a detected overthrust condition of the gas turbine. Diverting some of the fuel flow in this manner brings about a reduction in the thrust, allowing the overthrust condition to be controlled without resorting to a complete shut down of the gas turbine.

Growing community of inventors

Ashby-de-la-Zouch, United Kingdom

Stephen Granville Garner