AIRCRAFT HEATING AND VENTILATING SYSTEM

• US 3,825,212 A
• Filed: 07/10/1973
• Issued: 07/23/1974
• Est. Priority Date: 07/10/1973
• Status: Expired due to Term

• Current Assignee: George L. Petitgout, John J. Karpis, Walter Darges, Walter G. Witbeck
• Original Assignee: George L. Petitgout, John J. Karpis, Walter Darges, Walter G. Witbeck
• Inventors: Darges, Walter, Karpis, John J., Petitgout, George L., Witbeck, Walter G.
• Primary Examiner(s): King, Lloyd L.
• Assistant Examiner(s): Reese, Randolph A.
• Application Number:
  US05/377,982
• Time in Patent Office: 378 Days
• Field of Search: 244/118P 98/1.5 165/16 237/12.3A 236/13,49 55/347,348,457
• US Class Current: 244/118.5
• CPC Class Codes: B64D 13/08 the air being heated or cooled

Abstract

A heating and ventilating system, for use in aircraft, which provides a constant flow of air to the aircraft cabin is described. Ambient air is mixed with bleed air from the compressor stage of a turbine engine. The mixture of ambient and bleed air is propelled into the aircraft cabin by a constant R.P.M. blower. Prior to entering the cabin the mixed air may pass through a water and particle separator. A suitable control system is provided which maintains a pre-selected temperature by varying the amount of bleed air introduced into the system.

Claims

1. A heating and ventilating system which provides a constant mass flow of air per unit time for use in non-pressurized aircraft having a turbine engine which has a compressor stage, and a cabin, which comprises:

a first duct having two ends, one end communicating with ambient air;

a mixing unit connected to the remaining end of said first duct;

a blower unit including a duct having first and second ends, a fan positioned in said blower duct, and a constant RPM motor connected to said fan for propelling air through said blower duct, said blower unit connected to said mixing unit at said first end of said blower duct so that air may communicate therewith;

a second duct connected to said blower unit at said second end of said blower duct and to the aircraft cabin so that air may be communicated from the blower unit to the aircraft cabin;

a bleed air valve connected to the compressor stage of the aircraft turbine engine and to said mixing unit so that air may pass from the compressor stage of the engine to said mixing unit through said valve; and

a control means for varying the position of said valve in response to the cabin temperature.

2. The heating and ventilating system of claim 1 which further comprises a particle separator, having first and second ends, located between said blower unit and the aircraft cabin by connecting said first end of said particle separator to said second end of said blower duct and connecting said second end of said particle separator to said second duct thereby permitting air to pass through said separator to the aircraft cabin.

3. The heating and ventilating system of claim 2 wherein said particle separator includes a plurality of separator elements each of which include:

a vortex generator;

a first tube located concentrically about said vortex generator; and

an outlet tube located within said first tube, secured with respect thereto, downstream from said vortex generator, said second tube having a smaller diameter than said first tube so that debris carried by air entering said first tube will be thrown outward by centrifugal force with the result that air which enters said second tube will be relatively free of debris.

4. The heating and ventilating system of claim 1 wherein said control means includes safety means for preventing air having a temperature greater than a predetermined value from entering the aircraft cabin.

5. The heating and ventilating system of claim 4 wherein said safety means includes a temperature sensor located in said second duct and means for closing said valve when said sensor detects a temperature exceeding the predetermined value.

6. The heating and ventilating system of claim 4 wherein said control means includes means for temperature selection;

means for measuring actual cabin temperature;

signal means for generating a signal in response to a difference between selected and actual temperatures, an actuator connected to said bleed air valve and adapted to open and close said valve in response to the signal from said signal generating means whereby the position of said valve is a function of the difference between selected and actual cabin temperature.

7. The heating and ventilating system of claim 6 wherein said control means further includes a valve responsive to said signal means;

and wherein said actuator is operated by the bleed air pressure, said actuator having a pneumatic duct passing therethrough, connected to said valve thereby permitting air to communicate therewith;

said actuator adapted to be responsive to the pressure in said pneumatic duct thereby causing said bleed air valve opening to be responsive to said valve.

8. The heating and ventilating system of claim 1 wherein said mixing unit includes;

a tube, connected at one end to said first duct and connected at its remaining end to said first end of said blower unit, having orifices in said tube uniformly spaced about its circumference; and

an annular collar encompassing that portion of said tube having orifices therein, said collar being connected to said bleed air valve so that hot engine bleed air may communicate with said blower duct after being substantially uniformly mixed with outside ambient air, the ambient air communicating with said mixing unit through said first duct.

9. A heating and ventilating system for providing substantially constant air flow in non-pressurized aircraft having a cabin and a turbine engine which has a compressor stage, which comprises:

a first duct having two ends, one end communicating with ambient air;

a mixing unit connected to the remaining end of said first duct;

a blower, having a constant R.P.M. motor so as to provide a constant flow of air, connected to said mixing unit so that air may be forced to communicate therewith;

a second duct connected to said blower unit and to the aircraft cabin so that air may be communicated from the blower unit to the aircraft cabin;

a bleed air valve connected to the compressor stage of the aircraft turbine engine and to said mixing unit so that the air may pass from the compressor stage of the engine to said mixing unit through said valve; and

a control means for varying the position of said valve in response to the cabin temperature.