System and method for maintaining a consistent temperature gradient across an electronic display

• US 9,594,271 B2
• Filed: 04/08/2014
• Issued: 03/14/2017
• Est. Priority Date: 03/26/2008
• Status: Active Grant

• Current Assignee: Manufacturing Resources International, Inc.
• Original Assignee: Manufacturing Resources International, Inc.
• Inventors: Dunn, William, Tran, Chris, Hubbard, Tim
• Primary Examiner(s): Nguyen, Sang V
• Application Number:
  US14/247,658
• Publication Number:
  US 20140313458A1
• Time in Patent Office: 1,071 Days
• US Class Current: 1/1
• CPC Class Codes: F28F 3/02 Elements or assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with recesses, with corrugations F28F3/08 takes precedence
• CPC Class Codes: F28F 3/12 Elements constructed in the shape of a hollow panel, e.g. with channels F28D1/02, F28D1/03 take precedence
• CPC Class Codes: G02F 1/0105 Illuminating devices
• CPC Class Codes: G02F 1/133385 with cooling means, e.g. fans
• CPC Class Codes: G02F 2201/36 Airflow channels, e.g. constructional arrangements facilitating the flow of air
• CPC Class Codes: H05K 5/0017 with operator interface units
• CPC Class Codes: H05K 7/20136 Forced ventilation, e.g. by fans H05K7/202 takes precedence
• CPC Class Codes: H05K 7/20154 Heat dissipaters coupled to components
• CPC Class Codes: H05K 7/20972 Forced ventilation, e.g. on heat dissipaters coupled to components

Abstract

An electronic display which can be mounted above a paved surface in an outdoor environment. A surface or plate is placed behind the electronic display to define a gap where cooling air can be drawn through said gap in order to cool the electronic display. A plurality of ribs may be placed within the gap and in thermal communication with the electronic display. The density of the ribs may be varied according to the inlet and exhaust openings for the cooling air. The ribs may be placed at a higher density near the exhaust to account for the increase in temperature of the cooling air as it travels through the gap.

Claims

1. An electronic display assembly with forced-air cooling comprising:

a housing having a front side, a rear side, a top and a bottom;

an electronic display located within the housing so as to be viewable along the front side thereof;

a thermally conductive plate located behind the electronic display and in thermal communication therewith, a space between the plate and the rear side of the housing defining a gap, the plate engaging the housing so as to form a contaminant barrier between the electronic display and the gap;

an external air inlet opening at located near the top of the housing and in flow communication with the gap;

an external air exhaust opening located near the bottom of the housing and in flow communication with the gap, the air exhaust opening residing at a lower elevation than the air inlet opening when the electronic display is in an operating orientation; and

a fan in communication with the gap and operative to produce an air inlet opening-to-air exhaust opening directed airflow through the gap;

wherein, operation of the fan will cause external air from near the to of the housing to be moved through the air inlet opening and passed through the gap before being exhausted through the air exhaust opening at located near the bottom of the housing.

2. The electronic display assembly of claim 1 wherein:

said electronic display is a liquid crystal display.

3. The electronic display assembly of claim 1 wherein:

said fan is placed adjacent to the external air exhaust opening.

4. The electronic display assembly of claim 1 wherein:

said electronic display is an LED display.

5. The electronic display assembly of claim 1 wherein:

said electronic display is an OLED display.

6. The electronic display assembly of claim 1 further comprising:

a plurality of thermally conductive ribs placed within the gap and in thermal communication with the electronic display via contact with the thermally conductive plate.

7. The electronic display assembly of claim 6 wherein:

said thermally conductive ribs are metallic.

8. The electronic display assembly of claim 6 wherein:

said ribs are placed at a higher density near the bottom of the display housing, and placed at a lower density near the top of the display housing.

9. The electronic display assembly of claim 6 wherein:

said ribs have an I beam cross-section.

10. The electronic display assembly of claim 6 wherein:

said ribs have a rectangular cross-section.

11. A liquid crystal display assembly comprising:

a backlight located behind a liquid crystal display assembly, the backlight having a top portion and a bottom portion relative to the ground when the electronic display assembly is in an operating orientation;

a surface located behind and substantially parallel to the backlight, a space between the backlight and the surface defining a gap;

an air inlet opening located near the top portion of the backlight and in flow communication with the gap, the air inlet opening having a width at least half the width of the backlight;

an air exhaust opening located near the bottom portion of the backlight and in flow communication with the gap;

a plurality of thermally conductive ribs located in the gap with one side of the ribs in thermal communication with the backlight the density of ribs near the bottom portion of the backlight being greater than the density of ribs near the top portion of the backlight.

12. The liquid crystal display assembly of claim 11 further comprising:

a fan in flow communication with said gap and operative to produce an air inlet opening-to-air exhaust opening directed airflow through said gap.

13. The liquid crystal display assembly of claim 11 wherein:

an opposite side of the thermally conductive ribs is in thermal communication with the surface, such that heat from the backlight is transferable through the ribs to the surface.

14. The liquid crystal display assembly of claim 11 wherein:

the density of the ribs near the bottom of the backlight is at least twice the density of the ribs near the top of the backlight.

15. The liquid crystal display assembly of claim 11 wherein:

the backlight comprises a plurality of LEDs mounted on a metal core printed circuit board.

16. The liquid crystal display assembly of claim 15 wherein:

the metal core printed circuit board forms a rear side of the LED backlight and is in conductive thermal communication with the ribs.

17. The liquid crystal display assembly of claim 16 wherein:

the ribs have any one of the following cross-sections;

I-beam, hollow square, hollow rectangular, solid rectangular, solid square, ‘

T’

, ‘

Z’

, and honeycomb.

18. An electronic display assembly with a forced-air cooling feature comprising:

a housing having a top and a bottom relative to the ground;

a viewable electronic display within the housing;

a backlight located behind the electronic display;

a plate located behind the backlight, with a space between the backlight and the plate defining a gap that is open to external air;

a plurality of thermally conductive ribs located within the gap and in conductive thermal communication with the backlight; and

a fan in flow communication with the external air and with the gap, the fan operative to produce a top-to-bottom directed airflow through the gap;

wherein, operation of the fan will cause external air from near a top of the gap to be moved through the gap before being exhausted from a bottom of the gap.

19. The electronic display assembly of claim 18 wherein:

the density of ribs near the bottom of the housing is greater than the density of ribs near the top of the housing.

20. The electronic display assembly of claim 19 wherein:

the electronic display is an LED-backlit liquid crystal display, and the LED backlight is in conductive thermal communication with the ribs.