Direct air cooling system for airborne electronics

• US 4,674,704 A
• Filed: 12/03/1985
• Issued: 06/23/1987
• Est. Priority Date: 12/03/1985
• Status: Expired due to Fees

• Current Assignee: The United States of America As Represented By The Secretary of Agriculture
• Original Assignee: United States Of America As Represented By The Secretary Of The Air Force
• Inventors: Buckley, John J., Altoz, Frank E.
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US06/804,034
• Time in Patent Office: 567 Days
• Field of Search: 244/1 R, 244/117 A, 244/53 B, 244/57, 62/DIG. 5, 62/406, 62/407, 62/408, 62/410, 62/411, 62/412, 62/241, 98/1.5, 165/44, 361/383, 361/384
• US Class Current: 244/1.00R
• CPC Class Codes: B64D 2241/00 NACA type air intakes
• CPC Class Codes: H05K 7/20136 Forced ventilation, e.g. by fans H05K7/202 takes precedence
• CPC Class Codes: Y10S 62/05 Aircraft cooling

Abstract

A direct air cooling system 12 for electronics carried by aircraft. The cooling system provides a submerged air scoop 16 which directs outside air to several electronic modules 14. The air flows through passages 76 in the modules 14 which are adjacent to circuit boards 74, 78 bearing discrete electronic components 88. A foil layer 86 and aluminum fin stock help transfer heat from the electronic components to the directed air. Heated air is then exhausted through exhaust port 24 or 28.

Claims

1. A direct air cooling system for aircraft electronics which comprises:

(a) a submerged air scoop for bringing an air flow from the exterior of an aircraft to its interior wherein said air scoop comprises a vacuum slot for drawing off boundary layer air from the air flow passing through said air scoop in order to avoid air flow separation and stagnation,

(b) an inlet air duct for directing said air flow to electronic modules requiring cooling wherein said electronic modules comprise a multitude of electronic circuit board assemblies comprising circuit boards, discrete heat producing electronic components, a heat spreader and air passages adjacent to said circuit boards wherein said air passages are connected to said air inlet duct and comprise theremally conductive fin stock positioned to produce a high capacity heat transfer area where air from said inlet duct is used to cool said circuit boards and discrete heat producing components via said heat spreader; and

(c) an air exit port duct connected to said air passages for exhausting air to an exhaust port on the exterior of said aircraft.

2. The direct air cooling system of claim 1 wherein said air scoop further comprises a valve for controlling air flow through said scoop.

3. The direct air cooling system of claim 1 further comprising a fan for supplying air flow when said aircraft is at rest.

4. The direct air cooling system of claim 1 wherein said inlet duct further comprising a debris trap for removing contaminants from said air flow.

5. A direct air cooling system for electronics carried aboard an aircraft comprising:

(a) a submerged air inlet exposed to air flowing past said aircraft;

(b) a relatively low pressure slot in said submerged air inlet for removing high pressure boundary layer air from said inlet;

(c) an air control valve for selectively controlling air flow through said submerged air inlet;

(d) an air duct system fluidly connected to said subxerged air inlet comprising;

(i) contaminant traps to remove contaminants from air flowing through said air duct system, and

(ii) a fan for inducing air flow when air is not flowing past said aircraft;

(e) an electronic module fluidly connected to said air duct system wherein cooling air from said air duct system flow directly through air passages in said electronic module adjacent to circuit boards, said circuit boards being in close proximity to discrete heat producing electronic components; and

(f) an air exit for exhausting air heated by said electronic components.

6. The direct air cooling system of claim 5 wherein said air passages further comprise thermally conductive fin stock positioned to increase the heat transfer area between the cooling air and the circuit boards.

7. The direct air cooling system of claim 5 wherein said electronic modules further comprise a foil heat spreader interspaced between said circuit board and said air passages in order to spread the heat produced by the heat producing electronic components and to facilitate heat transfer between said circuit boards and said air flow.