Composite aerostructure with integrated heating element

• US 10,457,405 B1
• Filed: 04/24/2019
• Issued: 10/29/2019
• Est. Priority Date: 04/24/2018
• Status: Active Grant

• Current Assignee: Qarbon Aerospace LLC
• Original Assignee: Triumph Aerostructures LLC (Triumph Group, Inc.)
• Inventors: Hardman, Kyle B., Calder, Mark A., Derx, Ian C.
• Primary Examiner(s): Ellis, Christopher P
• Application Number:
  US16/393,519
• Publication Number:
  US 20190322375A1
• Time in Patent Office: 188 Days
• Field of Search: 244134 D
• CPC Class Codes: B29C 70/882 partly or totally electrically conductive, e.g. for EMI shielding conductive floors or floor coverings H05F3/025; EMI shielding in general H05K9/00
• CPC Class Codes: B29K 2071/00 Use of polyethers , e.g. PEEK, i.e. polyether-etherketone or PEK, i.e. polyetherketone or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2105/101 Oriented
• CPC Class Codes: B29K 2307/04 Carbon
• CPC Class Codes: B29K 2995/0005 Conductive
• CPC Class Codes: B29L 2031/3076 Aircrafts blades, propellers B29L2031/08
• CPC Class Codes: B32B 2250/03 3 layers
• CPC Class Codes: B32B 2250/05 5 or more layers
• CPC Class Codes: B32B 2260/021 Fibrous or filamentary layer layers of natural mineral fibres or particles being impregnated in a plastic substance B32B19/02
• CPC Class Codes: B32B 2260/046 Synthetic resin
• CPC Class Codes: B32B 2262/106 Carbon fibres, e.g. graphite fibres
• CPC Class Codes: B32B 2307/202 Conductive
• CPC Class Codes: B32B 2457/00 Electrical equipment
• CPC Class Codes: B32B 2605/18 Aircraft blades, propellers B32B2603/00
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 27/288 comprising polyketones
• CPC Class Codes: B32B 7/025 Electric or magnetic properties
• CPC Class Codes: B64D 15/12 by electric heating electric heating elements in general H05B
• CPC Class Codes: B64D 15/22 Automatic initiation by icing detector
• CPC Class Codes: B64D 2033/0233 comprising de-icing means
• CPC Class Codes: B64D 33/02 : of combustion air intakes air intakes for gas-turbine plants or jet-propulsion plants per se F02C7/04; air intakes for combustion engines in general F02M35/00
• CPC Class Codes: H05B 2203/003 : using serpentine layout
• CPC Class Codes: H05B 2214/02 : Heaters specially designed for de-icing or protection against icing
• CPC Class Codes: H05B 3/145 : Carbon only, e.g. carbon black, graphite
• CPC Class Codes: H05B 3/26 : heating conductor mounted on insulating base for transparent areas H05B3/84, H05B3/86
• CPC Class Codes: H05B 3/286 : the insulating material being an organic material, e.g. plastic
• CPC Class Codes: Y02T 50/40 : Weight reduction

Abstract

A heated composite structure and a method for forming a heated composite structure. The structure includes carbon fibers embedded within a thermoplastic matrix. The carbon fibers are connected with first and second electrodes that are configured to be connected with an electric source such that applying current to the electrodes causes current to flow through the embedded carbon fibers to provide resistive heating sufficient to heat the composite structure to impede formation of ice on the composite structure.

Claims

1. A heated aerostructure, comprising:

a composite structure, comprising;

a reinforced thermoplastic upper layer forming a load bearing element of the aerostructure wherein the thermoplastic of the upper layer has a first glass transition temperature;

a reinforced thermoplastic lower layer forming a load bearing element of the aerostructure wherein thermoplastic of the lower layer has a second glass transition temperature;

a thermoplastic heater layer wherein the thermoplastic of the heater layer has a third glass transition temperature and the heater layer comprises;

a plurality of electrically conductive fibers;

a first electrode electrically connected with the conductive fibers; and

a second electrode electrically connected with the conductive fibers, so that the conductive fibers provide an electrical pathway between the first electrode and the second electrode;

wherein the conductive fibers of the thermoplastic heater layer are substantially similar to the reinforcing fibers of the upper layer and the lower layer;

a first fiber reinforced thermoplastic insulative layer disposed between the heater layer and the upper layer wherein the thermoplastic of the first insulative layer has a fourth glass transition temperature;

a second fiber reinforced thermoplastic insulative layer disposed between the heater layer and the lower layer wherein the thermoplastic of the second insulative layer has a fifth glass transition temperature;

wherein the third glass temperature is within 25 percent of the glass transition temperature of the first and second glass temperature;

a sensor operable to sense a characteristic indicative of the formation of ice on the upper layer;

a controller connected with the sensor and an electrical power source for controlling the power provided to the first electrode;

wherein the first electrode and the electrically conductive fibers are connected such that electric power applied to the first electrode is conducted to the electrically conductive fibers to provide resistive heating sufficient to heat the composite structure to impede formation of ice on the composite structure or to remove ice formed on the composite structure.

2. The heated aerostructure of claim 1 wherein the controller is operable to control the electrical power provided to the first electrode in response to signals received from the sensor.

3. The heated aerostructure of claim 1 wherein the plurality of electrically conductive fibers of the heater layer comprise unidirectional carbon fiber reinforced thermoplastic.

4. The heated aerostructure of claim 3 wherein the electrically conductive fibers have a first end electrically connected with the first electrode and a second end electrically connected with the second electrode and substantially all of the carbon fibers extend continuously from the first end to the second end.

5. The heated aerostructure of claim 4 wherein the heater layer comprises a convoluted path between the first and second electrodes.

6. The heated aerostructure of claim 4 comprising a second heater layer independently operable from the heater layer and a third electrically insulative layer insulating the second heater layer from the heater layer.

7. The heated aerostructure of claim 4 wherein the composite structure comprises a portion of an airfoil.

8. The heated aerostructure of claim 1 wherein the upper layer comprises a plurality of carbon fiber reinforced thermoplastic lamina.

9. The heated aerostructure of claim 1 wherein the thermoplastic of each of the heater layer, the upper layer and the lower layer are fused with the thermoplastic in adjacent layers.

10. The heated aerostructure of claim 1 wherein the third glass transition temperature is within 25% of the fourth and fifth glass transition temperatures.

11. The heated aerostructure of claim 1 wherein the heater layer and at least one of the upper layer and the lower layer comprise a semicrystalline thermoplastic in the polyaryletherketone family.