Electro-pneumatic de-icer

1. An electro-pneumatic de-icer for an airfoil, comprising:

an electric generator configured to convert mechanical energy from an engine to electricity;

a first electric motor configured to electrically power a compressor for compressing air;

an air-storage tank fluidly coupled to the compressor for storing compressed air;

a pressure regulator for regulating the pressure of the compressed air exiting the air-storage tank to provide a regulated high-pressure air;

a second electric motor configured to electrically power a vacuum pump for producing negative pressure;

a plurality of pneumatic boots coupled to the airfoil;

a plurality of control valves each fluidly coupled with the plurality of pneumatic boots, respectively;

a manifold configured to fluidly couple the pressure regulator and the vacuum pump with the plurality of control valves for simultaneous operation of the control valves; and

wherein each of the plurality of control valves includes a first port fluidly coupled to the pressure regulator via the manifold, a second port fluidly coupled to the vacuum pump via the manifold, and a third port fluidly coupled to a respective one of the plurality of pneumatic boots, wherein each of the control valves is configured to cycle between supplying regulated high-pressure air through the first port to inflate a respective one of the pneumatic boots and withdrawing air through the second port to deflate a respective one of the pneumatic boots for cracking accumulated ice on the airfoil.

2. The electro-pneumatic de-icer of claim 1 , wherein the compressor and vacuum pump are electrically powered by an electric motor having a common shaft therebetween.

3. The electro-pneumatic de-icer of claim 2 , wherein the common shaft further comprises an electric clutch for intermittently engaging and powering the compressor to compress air for storing in the air-storage tank.

4. The electro-pneumatic de-icer of claim 1 , further comprising an unloading valve fluidly coupled to an outlet of the compressor for venting excess compressed air from the compressor such that the compressor operates continuously.

5. The electro-pneumatic de-icer of claim 4 , wherein the unloading valve comprises a spring for biasing the unloading valve open for venting excess compressed air, and the unloading valve is intermittently electrically powered to close for supplying high-pressure air to the air-storage tank.

6. The electro-pneumatic de-icer of claim 1 , wherein the regulated high-pressure air is between 10 psig and 30 psig.

7. An airfoil de-icing system, comprising:

an electrically-powered compressor for compressing air;

a pressurized vessel having an intake coupled to the compressor for receiving and storing compressed air and an exit port for providing high-pressure air;

a controller configured to intermittently turn the electrically-powered compressor on and off for avoiding over-pressurization of the pressurized vessel;

an electrically-powered vacuum pump configured to operate continuously for providing a constant source of negative pressure;

a plurality of airfoil pneumatic boots;

a plurality of three-way valves located between 1) the exit port of the pressurized vessel, 2) the electrically-powered vacuum pump, and 3) the plurality of airfoil pneumatic boots, wherein each of the plurality of three-way valves is configured to alternate supply of negative pressure with supply of high-pressure air to a respective one of the plurality of airfoil pneumatic boots, thereby cyclically deflating and inflating the each airfoil pneumatic boot for cracking accumulated ice on the airfoil; and

a manifold configured to fluidly couple the pressurized vessel and the vacuum pump with the plurality of three-way valves such that the plurality of airfoil pneumatic boots are capable of being simultaneously inflated and deflated.

8. The airfoil de-icing system of claim 7 , wherein the source of negative pressure is substantially derived from the intake to the compressor.

9. The airfoil de-icing system of claim 7 , further comprising:

an electric motor having a common shaft mechanically coupled to the compressor and the vacuum pump; and

an electric clutch mechanically coupled to the common shaft for intermittently powering the compressor.

10. The airfoil de-icing system of claim 7 , wherein the high-pressure air is pressurized to a gauge-pressure of more than 125 psig and less than 150 psig.

11. An airfoil de-icing method, comprising:

compressing air with an electrically-powered compressor;

storing high-pressure air from the compressor in an air-storage tank;

regulating the high-pressure air from the accumulator using a regulator for providing a regulated high-pressure air;

delivering the regulated high-pressure air from the air-storage tank via a manifold to a plurality of pneumatic boots located along an airfoil to inflate the plurality of pneumatic boots simultaneously;

providing a negative-pressure source;

deflating the plurality of pneumatic boots with the negative-pressure source via the manifold; and

controlling a plurality of control valves for alternating cyclically between inflating and deflating the plurality of pneumatic boots, respectively, for cracking accumulated ice on the airfoil.

12. The airfoil de-icing method of claim 11 , wherein compressing air is performed by intermittently providing power to the electrically-powered compressor for supplying high-pressure air to the air-storage tank when the pressure in the air-storage tank drops below a predetermined level.

13. The airfoil de-icing method of claim 11 , wherein an electric clutch is used for intermittently providing power from a shaft of an electric motor to the compressor for supplying high-pressure air to the air-storage tank.

14. The airfoil de-icing method of claim 11 , wherein the compressor operates continuously and an unloading valve is used for intermittently venting air when pressure in the air-storage tank reaches a predetermined level.

15. The airfoil de-icing method of claim 11 , wherein an electric motor is used for driving a vacuum pump continually for providing a constant negative-pressure source for deflating the plurality of pneumatic boots.

16. The airfoil de-icing method of claim 11 , wherein an intake to the compressor is configured for operating at a negative pressure for providing a negative-pressure source without the need for a vacuum pump.

17. The airfoil de-icing method of claim 11 , wherein the plurality of control valves are commanded to inflate and deflate the plurality of pneumatic boots simultaneously.