Shape memory material actuation
AssigneeROLLS-ROYCE plc
InventorJohn R. Webster
Life of this patent
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Abstract
A shape memory material inductive heating arrangement comprising an array of coils capable of carrying an alternating electrical current and generating a magnetic field, a shape memory element having a first modulus and a second modulus, the second modulus greater than the first, characterised in that the array of coils and shape memory element are in effective range so that when an alternating current is passed through the coils the shape memory element is subject to the magnetic field and heated thereby, the induced heat sufficient to change the modulus of the shape memory material from the first to the second modulus.
Claims27
1-28. (canceled)
A method of changing a shape of an exhaust nozzle of a gas turbine engine comprising:
- passing an alternating current through an array of flat coils to generate a magnetic field;
- and
- using the magnetic field to generate an eddy current in a shape memory element in the form of a sheet to inductively heat the shape memory element to change a modulus of the shape memory element from a first stress-strain characteristic to a second state having a second stress-strain characteristic, such that the change in the modulus between the first and the second states effects a change of a shape of the exhaust nozzle.
A method of changing a shape of an exhaust nozzle of a gas turbine engine comprising:
- passing an alternating current through an array of flat coils to generate a magnetic field, wherein the array of flat coils bend with the exhaust nozzle, during use;
- and
- using the magnetic field to generate an eddy current in a shape memory element in the form of a sheet to inductively heat the shape memory element to change a modulus of the shape memory element from a first stress-strain characteristic to a second state having a second stress-strain characteristic, such that the change in the modulus between the first and the second states effects a change of a shape of the exhaust nozzle.
Dependencies are inferred from the claim text.