Avionics Chassis

• US 20100321890A1
• Filed: 06/19/2009
• Published: 12/23/2010
• Est. Priority Date: 06/19/2009
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Streyel, John Jay, Coxon, Danny Weldon, Vander Ploeg, Benjamin Jon, Steenwyk, Meredith Marie
• Granted Patent: US 8,023,267 B2
• Time in Patent Office: Days
• US Class Current: 361/704
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H05K 7/20545 Natural convection of gaseous coolant; Heat transfer by conduction from electronic boards

Abstract

An avionics chassis comprises a housing having opposing walls, a pair of spaced card rails with one rail mounted to each of the opposing walls where each rail has a channel to define an effective slot having a predetermined height extending between the rails. The avionics chassis also includes a circuit card assembly comprising a printed circuit board and a thermal plane in overlying relationship with the printed circuit board, with the printed circuit board defining a first primary plane, and the thermal plane defining a second primary plane. The spatial relationship between the printed circuit board and the thermal plane is such that the first and second primary planes are located within the slot when the circuit card assembly is mounted to the card rail assembly and the thermal plane is conductively coupled to at least one of the rails to form a first conductive path from the thermal plane to at least one of the opposing walls and the printed circuit board is conductively coupled to at least one of the rails to form a second conductive path from the printed circuit board to at least one of the opposing walls.

Claims

1. An avionics chassis comprising:

a housing defining an interior and having opposing walls;

a card rail assembly comprising a pair of spaced rails, with each rail mounted to an opposite one of the opposing walls in thermal conductivity therewith, and each rail having a channel to define an effective slot having a predetermined height extending between the rails;

a circuit card assembly comprising a printed circuit board and a thermal plane in overlying relationship with the printed circuit board, with the printed circuit board defining a first primary plane, and the thermal plane defining a second primary plane;

wherein the spatial relationship between the printed circuit board and the thermal plane is such that the first and second primary planes are located within the slot when the circuit card assembly is mounted to the card rail assembly and the thermal plane is conductively coupled to at least one of the rails to form a first conductive path from the thermal plane to at least one of the opposing walls and the printed circuit board is conductively coupled to at least one of the rails to form a second conductive path from the printed circuit board to at least one of the opposing walls.

2. The avionics chassis of claim 1, wherein at least one of the thermal plane and printed circuit board directly contacts the corresponding rail to form the corresponding first or second conductive path.

3. The avionics chassis of claim 1, wherein the circuit card assembly further comprises a wedge lock for selectively locking the printed circuit board in the rails and the wedge lock is thermally conductive to form a portion of the corresponding first or second conductive path.

4. The avionics chassis of claim 1, wherein the thermal plane is made from at least one of a carbon fiber-reinforced composite and a carbon-carbon composite.

5. The avionics chassis of claim 4, wherein the carbon fibers are laid up such that the thermal plane is thermally conductive in at least one of a two-dimensional plane, a three-dimensional plane, and a one-dimensional plane.

6. The avionics chassis of claim 5, wherein the carbon fibers are laid up such that the thermal plane thermally conducts heat laterally towards the rails.

7. The avionics chassis of claim 1, wherein the thermal plane is made of pyrolytic carbon.

8. The avionics chassis of claim 1, wherein the printed circuit board comprises a heat producing component and the thermal plane comprises a thermal pad conductively coupling the heat producing component to the thermal plane to form part of the first conductive path.

9. The avionics chassis of claim 8, wherein the thermal pad is made from a thermally conductive material.

10. The avionics chassis of claim 8, wherein the thermal pad directly contacts the heat producing component.

11. The avionics chassis of claim 10, wherein the thermal pad is adjustable relative to the printed circuit board.

12. The avionics chassis of claim 1, wherein the printed circuit board further comprises thermally conductive side strips that are aligned with the card rails when the circuit card assembly is received within the slot to form part of the second conductive path.

13. The avionics chassis of claim 12, wherein the printed circuit board further comprises a heat producing component and at least one thermally conductive element extending from the heat producing component to at least one of the thermally conductive side strips.

14. The avionics chassis of claim 1, wherein the circuit card assembly further comprises a stiffener located between the printed circuit board and the thermal plane when the circuit card assembly is located within the slot.

15. The avionics chassis of claim 14, wherein a portion of the stiffener is located within one of the card rails when the circuit card assembly is located within the slot to form part of at least one of the first and second conductive paths.