Portable data routing device and method of use

• US 7,372,705 B1
• Filed: 02/01/2006
• Issued: 05/13/2008
• Est. Priority Date: 02/01/2006
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Spivey, Thomas, Winn, Tracy
• Primary Examiner(s): Gutierrez; Diego
• Assistant Examiner(s): Levi; Dameon E
• Application Number:
  US11/344,994
• Time in Patent Office: 832 Days
• Field of Search: 361/711, 361/709, 361/710, 361/707, 361/704, 361/688, 361/719, 361/721, 361/687, 361/720, 361/730, 361/752, 361/796, 361/797, 361/788, 174/16.1, 174/16.3, 174/50, 174/520, 165/80.3, 165/104.33
• US Class Current: 361/796
• CPC Class Codes: H05K 7/20445 the coupling element being an additional piece, e.g. thermal standoff

Abstract

A data communications device, such as a router, is configured for use in an outdoor environment. The router includes wireless communications circuit boards mounted within an environmentally sealed housing. The housing protects the circuit boards from exposure to extreme environmental conditions such as relatively high temperatures, rain, or snow to maintain the operability of the router. The router also includes a thermal transfer assembly disposed within the sealed housing that conducts heat away from the router'"'"'s circuit board components. Because the thermal transfer assembly operates using conduction rather than convection, the data communications device does not require the use of a fan assembly to remove heat from the circuit board components. This minimizes the overall size and weight of the data communications device, allowing the device to be deployed in a variety of outdoor locations, such as traffic signal poles, curb side cabinets, or vehicles.

Claims

1. A data communications device, comprising:

an environmentally sealed housing having a card chassis and at least one end cap coupled to the card chassis, the housing configured to provide a barrier between an inner space defined by the housing and an outer space;

a plurality of circuit boards disposed within the inner space of the housing, at least one of the plurality of circuit boards being configured to receive data from a source and direct data to a destination; and

a thermal transfer assembly adapted to thermally couple at least one circuit board component of the plurality of circuit boards to the housing, the thermal transfer assembly comprising;

a plate coupled to the at least one circuit board,

a thermal conductor disposed between the plate and the at least one circuit board, the thermal conductor being configured to provide thermal communication between a circuit board component of the at least one circuit board and the plate, and

a coupling element operable to thermally couple the plate to the housing;

wherein;

the card chassis defines a slot configured to support the conductive plate coupled to the at least one circuit board; and

the coupling element comprises a primary compression element and a secondary compression element, the secondary compression element of the coupling element is configured to move relative to the primary compression element of the coupling element to thermally couple the plate to the housing.

2. The data communications device of claim 1, wherein the plate comprises a first plate and a second plate, the at least one circuit board disposed between the first plate and the second plate.

3. The data communications device of claim 1, wherein the thermal conductor comprises a substantially compliant material adapted to conform to a surface of at least one of the plate and the circuit board component.

4. The data communications device of claim 1, wherein the plurality of circuit boards are configured as modular circuit boards.

5. The data communications device of claim 4, wherein each of the plurality of circuit boards comprises an interconnection element having a set of pins and a set of receptacles extending from opposing surfaces of the circuit board, the interconnection element operable to provide electrical coupling of the plurality of circuit boards.

6. The data communications device of claim 1, wherein the plurality of circuit boards are selected from the group consisting of a wireless transceiver card, an Ethernet switch card, a serial port interface card, and a router card.

7. The data communications device of claim 1, wherein the environmentally sealed housing comprises a gasket disposed between the at least one end cap and the card chassis, the housing configured to provide moisture protection to the plurality of circuit boards.

8. The data communications device of claim 1, wherein the chassis comprises an upper housing portion having a substantially curved profile.

9. The data communications device of claim 1, wherein the chassis comprises a lower housing portion having a substantially curved profile.

10. The data communications device of claim 1, wherein the at least one end cap comprises at least one interface connector and wherein the data communications device comprises a wiring card disposed between the at least one end cap and connection ports of at least one of the plurality of circuit boards, the wiring card configured to provide electrical communication between the at least one interface connector of the at least one end cap and the connection ports of the at least one of the plurality of circuit boards.

19. The data communications device of claim 2, wherein the coupling element comprises the primary compression element carried by the first plate, at least one secondary compression element carried by the primary compression element, and at least one compression adjustment mechanism carried by the at least one secondary compression element, the at least one compression adjustment mechanism being constructed and arranged to position the at least one secondary compression element between a first position to allow insertion of the first plate into the slot defined by the card chassis and a second position to secure and thermally couple the first plate to the housing.

20. The data communications device of claim 19, wherein:

each of the plurality of circuit boards comprises an interconnection element having a first connection portion extending from a first planar surface of the circuit board and a second connection portion extending from a second planar surface of the circuit board, the first surface opposing the second surface, the interconnection element constructed and arranged to provide electrical coupling between a first circuit board of the plurality of circuit boards, a second circuit board of the plurality of circuit boards disposed in proximity to the first connector portion of the first circuit board, and a third circuit board of the plurality of circuit boards disposed in proximity to the second connector portion of the first circuit board; and

the first plate is disposed in proximity to the first planar surface of the at least one circuit board and the second plate is disposed in proximity to the second planar surface of the at least one circuit board, the first plate defining at least one opening sized and arranged to frame the first connection portion and to allow electrical access to the first connection portion, and the second plate defining at least one opening sized and arranged to frame the second connection portion and to allow electrical access to the second connection portion.

21. The data communications device of claim 20, wherein the plate carries the thermal conductor disposed between the plate and the at least one circuit board, the thermal conductor being configured to provide thermal communication between the circuit board component of the at least one circuit board and the plate, wherein the thermal conductor comprises a compliant material adapted to conform to a surface of the circuit board component.

11. A data communications device, comprising:

an environmentally sealed housing having a card chassis and at least one end cap coupled to the card chassis, the housing configured to provide a barrier between an inner space defined by the housing and an outer space;

a plurality of circuit boards disposed within the housing, at least one of the plurality of circuit boards being configured to receive data from a source and direct data to a destination; and

a thermal transfer assembly adapted to thermally couple a circuit board component of at least one circuit board of the plurality of circuit boards to the

housing to transfer heat from a circuit board component to the housing via conduction;

wherein the thermal transfer assembly comprises;

a plate coupled to the at least one circuit board;

a compliant thermal conductor disposed between the plate and the at least one circuit board, the compliant thermal conductor being configured to thermally couple the circuit board component of the at least one circuit board to the plate; and

a coupling element operable to thermally couple the plate to the housing;

wherein the plate comprises a first plate and a second plate, the at least one circuit board disposed between the first plate and the second plate;

wherein;

the card chassis defines a slot configured to support the conductive plate coupled to the at least one circuit board; and

the coupling element comprises a primary compression element and a secondary compression element, the secondary compression element of the coupling element is configured to move relative to the primary compression element of the coupling element to thermally couple the plate to the housing.

12. The data communications device of claim 11, wherein the thermal conductor comprises a substantially compliant material adapted to conform to a surface of at least one of the plate and the circuit board component.

13. The data communications device of claim 11, wherein the plurality of circuit boards are configured as modular circuit boards.

14. The data communications device of claim 13, wherein each of the plurality of circuit boards comprises an interconnection element having a set of pins and a set of receptacles extending from opposing surfaces of the circuit board, the interconnection element operable to provide electrical coupling of the plurality of circuit boards.

15. The data communications device of claim 11, wherein the plurality of circuit boards are selected from the group consisting of a wireless transceiver card, an Ethernet switch card, a serial port interface card, and a router card.

16. The data communications device of claim 11, wherein the at least one end cap comprises at least one interface connector and wherein the data communications device comprises a wiring card disposed between the at least one end cap and connection ports of at least one of the plurality of circuit boards, the wiring card configured to provide electrical communication between the at least one interface connector of the at least one end cap and the connection ports of the at least one of the plurality of circuit boards.

17. A method for assembling a data communications device, comprising:

thermally coupling a circuit board to a thermally conductive plate, the thermally conductive plate having a compliant thermally conductive material in thermal communication with the thermally conductive plate and at least one circuit board component of the circuit board;

inserting the circuit board and thermally conductive plate within a slot of a card chassis of a data communications device housing; and

expanding a thermal coupling element within the slot to thermally couple the thermally conductive plate to the housing;

wherein expanding a thermal coupling element within the slot to thermally couple the thermally conductive plate to the housing comprises;

actuating at least one compression adjustment mechanism of the thermal coupling element; and

positioning at least one secondary compression element relative to a primary compression element carried by the thermally conductive plate between a first position to allow insertion of the plate into the slot defined by the card chassis and a second position to secure and thermally couple the thermally conductive plate to the housing.

18. The method of claim 17, comprising coupling at least one end cap to the card chassis to form an environmentally sealed housing, the housing configured to provide a barrier between an inner space defined by the housing and an outer space.