Electromagnetic interference shielding and strain relief structures for coupled printed circuits

• US 9,888,562 B2
• Filed: 12/24/2012
• Issued: 02/06/2018
• Est. Priority Date: 12/24/2012
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Malek, Shayan, Wittenberg, Michael B., Cohen, Sawyer I., Shukla, Ashutosh Y.
• Primary Examiner(s): Aychillhum, Andargie M
• Application Number:
  US13/726,509
• Publication Number:
  US 20140177180A1
• Time in Patent Office: 1,870 Days
• Field of Search: 174250, 361749, 361748
• CPC Class Codes: H01R 12/79 connecting to rigid printed circuits or like structures
• CPC Class Codes: H01R 13/6595 with separate members fixing the shield to the PCB
• CPC Class Codes: H05K 1/0219 Printed shielding conductors for shielding around or between signal conductors, e.g. coplanar or coaxial printed shielding conductors
• CPC Class Codes: H05K 2201/0311 Metallic part with specific elastic properties, e.g. bent piece of metal as electrical contact
• CPC Class Codes: H05K 2201/0314 Elastomeric connector or conductor, e.g. rubber with metallic filler
• CPC Class Codes: H05K 2201/09063 Holes or slots in insulating substrate not used for electrical connections
• CPC Class Codes: H05K 2201/10189 Non-printed connector
• CPC Class Codes: H05K 2201/10409 Screws
• CPC Class Codes: H05K 3/363 by soldering
• CPC Class Codes: H05K 3/368 parallel to each other H05K3/361 takes precedence
• CPC Class Codes: H05K 7/142 Spacers not being card guides
• CPC Class Codes: H05K 9/0022 of components mounted on printed circuit boards [PCB] shields integrated within component packages H01L23/552; shields integrated within PCB H05K1/0218
• CPC Class Codes: Y10T 29/49126 Assembling bases

Abstract

Electrical components in an electronic device are mounted on substrates such as printed circuits. Printed circuits contain signal paths formed from metal traces. The signal lines in the signal paths of the printed circuits are coupled together using electrical connection structures such as printed circuit board-to-board connectors, contacts joined by anisotropic conductive film, or contacts joined using solder. Electrical connection structures may be surrounded by conductive resilient ring-shaped structures such as conductive foam structures or spring structures. The conductive foam structures may be provided with a metal layer with which the conductive foam structures are soldered to a ring of metal on a printed circuit. Strain relief structures may be formed from an elastomeric ring that surrounds the electrical connection structures or an overmolded plastic structure. Coating layers and conductive plastic may be used in providing strain relief structures with electromagnetic interference shielding capabilities.

Claims

1. Apparatus, comprising:

a first printed circuit having first signal paths;

a second printed circuit having second signal paths;

electrical connection structures that couple the first and second signal paths, wherein the electrical connection structures are interposed between the first and second signal paths, wherein the electrical connection structures comprise a first connector mounted to the first printed circuit and a second connector mounted to the second printed circuit, and wherein the first connector is coupled to the second connector, wherein the second connector is interposed between the first connector and the second printed circuit; and

a ring-shaped conductive electromagnetic interference shielding structure that is interposed between the first and second printed circuits and that surrounds the electrical connection structures.

2. The apparatus defined in claim 1 wherein the electrical connection structures comprise a printed circuit board-to-board connector.

3. The apparatus defined in claim 1 wherein the electrical connection structures comprise metal traces joined by a material selected from the group consisting of:

anisotropic conductive film and solder.

4. The apparatus defined in claim 1 wherein the ring-shaped conductive electromagnetic interference shielding structure comprises conductive polymer.

5. The apparatus defined in claim 1 wherein the ring-shaped conductive electromagnetic interference shielding structure comprises resilient rectangular ring structures.

6. The apparatus defined in claim 1 wherein the ring-shaped conductive electromagnetic interference shielding structure comprises multiple layers of metal interposed between multiple respective layers of foam.

7. The apparatus defined in claim 1 further comprising openings in the second printed circuit and a metal bracket that has portions that pass through the openings.

8. The apparatus defined in claim 1 wherein the first connector comprises a first contact pin coupled to the first signal paths and the second connector comprises a second contact pin coupled to the second signal paths, and wherein the first contact pin is coupled to the second contact pin.

9. The apparatus defined in claim 1 wherein the first connector comprises a first plastic body and a first set of contact pins, and wherein the second connector comprises a second plastic body and a second set of contact pins that mate with the first set of contact pins.

10. Apparatus, comprising:

a first printed circuit having first signal paths;

a second printed circuit having second signal paths;

electrical connection structures that couple the first and second signal paths; and

a ring-shaped, conductive, resilient electromagnetic interference shielding structure that is interposed between the first and second printed circuits and that surrounds the electrical connection structures, wherein the ring-shaped, conductive, resilient electromagnetic interference shielding structure comprises first and second opposing surfaces, a peripheral side surface, and a metal layer on the first surface and at least one of the second surface and the peripheral side surface.

11. The apparatus defined in claim 10 further comprising a metal trace on the first printed circuit that surrounds the electrical connection structures, wherein the ring-shaped, conductive, resilient electromagnetic interference shielding structure is shorted to the metal trace on the first printed circuit.

12. The apparatus defined in claim 10 wherein the metal layer is a rectangular metal layer, the apparatus further comprising solder that couples the rectangular metal layer to the metal trace on the first printed circuit.

13. The apparatus defined in claim 12 further comprising a metal trace on the second printed circuit that is shorted to the ring-shaped, conductive, resilient electromagnetic interference shielding structure.

14. The apparatus defined in claim 13 wherein the metal trace on the second printed circuit has a rectangular ring shape that surrounds the electrical connection structures.

15. The apparatus defined in claim 14 wherein the electrical connection structures comprise a printed circuit board-to-board connector.

16. The apparatus defined in claim 15 wherein the first printed circuit comprises a rigid printed circuit board and wherein the second printed circuit comprises a flexible printed circuit, the apparatus further comprising a metal bracket that covers at least part of the flexible printed circuit.

17. The apparatus defined in claim 16 further comprising screws that hold the metal bracket in place on the flexible printed circuit, wherein the screws do not extend through the flexible printed circuit.

18. The apparatus defined in claim 16 further comprising stiffening structures interposed between the metal bracket and the flexible printed circuit.

19. The apparatus defined in claim 10 wherein the ring-shaped conductive electromagnetic interference shielding structure comprises a rectangular foam ring, wherein the peripheral side surface is covered with patterned metal having openings, and wherein the openings are completely surrounded by the patterned metal layer.

20. Apparatus, comprising:

a first printed circuit having first signal paths;

a second printed circuit having second signal paths;

electrical connection structures that couple the first and second signal paths; and

ring-shaped conductive electromagnetic interference shielding structures that are interposed between the first and second printed circuits and that surround the electrical connection structures, wherein the ring-shaped conductive electromagnetic interference shielding structures comprise metal spring structures.

21. The apparatus defined in claim 20 wherein the metal spring structures are coupled to ground signal paths on the first and second printed circuits.

22. The apparatus defined in claim 20 wherein the metal spring structures comprise a rectangular ring-shaped metal spring that surrounds the electrical connection structures.

23. The apparatus defined in claim 20 wherein the metal spring structures comprise a plurality of separate, metal springs that surround the electrical connection structures, wherein each of the plurality of separate, metal springs are separated from one another by a plurality of respective gaps.