Shield can having tapered wall ends for surface mounting and radiotelephones incorporating same

• US 6,175,077 B1
• Filed: 02/09/1999
• Issued: 01/16/2001
• Est. Priority Date: 02/09/1999
• Status: Expired due to Term

• Current Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Original Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Inventors: Lund, Richard C., Mendolia, Gregory S.
• Primary Examiner(s): Kincaid, Kristine
• Assistant Examiner(s): Ngo, Hung V
• Application Number:
  US09/246,971
• Time in Patent Office: 707 Days
• Field of Search: 174/35.R, 174/35.MS, 361/816, 361/818, 361/753, 361/799, 361/800, 257/659, 257/660
• US Class Current: 174/384
• CPC Class Codes: H05K 2201/10371 Shields or metal cases
• CPC Class Codes: H05K 2201/10803 Tapered leads, i.e. leads having changing width or diameter
• CPC Class Codes: H05K 3/341 Surface mounted components
• CPC Class Codes: H05K 9/0039 Galvanic coupling of ground layer on printed circuit board [PCB] to conductive casing printed shielding conductors, ground planes or power planes for reduction of cross-talk or noise in printed circuits H05K1/0218
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

Electromagnetic shielding devices are provided with walls having a pair of opposing, generally parallel side faces that terminate at a tapered end portion. Each tapered end portion is configured to be surface mounted to a respective conductive portion (e.g., mounting pad) of an electronic substrate via a pair of solder fillets. The tapered end portion of each wall includes a pair of elongate end faces symmetrical about a plane that is generally parallel to, and equidistant between, the wall side faces. The end faces define a pair of elongated cavities with respect to a PCB that are configured to receive the solder fillets.

Claims

1. An electromagnetic shielding apparatus, comprising:

an electrically conductive frame having peripheral walls and opposite first and second open ends;

wherein each peripheral wall comprises;

a pair of opposite side faces terminating at a tapered end portion that is configured to be soldered to a conductive portion of an electronic substrate;

wherein a cross-sectional dimension of the tapered end portion decreases in a direction towards the conductive portion to define at least one cavity with respect to the conductive portion; and

wherein the cavity is configured to receive solder therewithin for securing the tapered end portion to the conductive portion; and

an electrically conductive cover configured to be secured to the frame to cover the first opening and thereby define an enclosure.

2. An electromagnetic shielding apparatus according to claim 1 wherein the side faces of each wall are generally parallel.

3. An electromagnetic shielding apparatus according to claim 2 wherein the tapered end portion of each wall comprises a pair of elongate end faces symmetrical about a plane generally parallel to and equidistant between the side faces of a respective wall, and wherein each end face in the pair abuts an edge of the corresponding end face of the pair and also abuts an edge of a respective side face.

4. An electromagnetic shielding apparatus according to claim 3 wherein the abutting end faces form an angle of between about 5 degrees and about 45 degrees.

5. An electromagnetic shielding apparatus according to claim 1 wherein each wall is formed from material having a higher melting point than a melting point of solder.

6. An electromagnetic shielding apparatus according to claim 1 wherein the cover and frame are formed from metalized polymeric material.

7. An electromagnetic shielding apparatus according to claim 1 wherein the conductive portion of the electronic substrate comprises a conductive mounting pad.

8. An electromagnetic shielding apparatus, comprising:

an electrically conductive frame, comprising;

a plurality of elongate metal walls;

wherein each wall includes a pair of opposing, generally parallel side faces terminating at a tapered end portion configured to be surface mounted to a respective conductive mounting pad on an electronic substrate via solder;

wherein the tapered end portion of each wall comprises a pair of elongate end faces symmetrical about a plane generally parallel to and equidistant between the side faces of a respective wall;

wherein each end face in the pair abuts an edge of the corresponding end face of the pair and also abuts an edge of a respective side face to define a pair of cavities with respect to a respective conductive mounting pad; and

wherein each cavity in the pair is configured to receive solder therewithin for securing a respective wall to a respective conductive mounting pad; and

an electrically conductive cover configured to be secured to the frame to define an enclosure.

9. An electromagnetic shielding apparatus according to claim 8 wherein the abutting end faces form an angle of between about 5 degrees and about 45 degrees.

10. An electromagnetic shielding apparatus according to claim 8 wherein each wall is formed from material having a higher melting point than a melting point of solder.

11. An electronic apparatus, comprising:

an electronic substrate; and

an electromagnetic shielding apparatus secured to the electronic substrate, comprising;

a frame, comprising;

a plurality of elongate electrically conductive walls;

wherein each wall includes a pair of opposing side faces terminating at a tapered end portion;

wherein each tapered end portion is secured to a respective conductive mounting pad on the electronic substrate via solder; and

wherein a cross-sectional dimension of each tapered end portion decreases in a direction towards a respective conductive mounting pad to define a cavity configured to receive solder therewithin; and

an electrically conductive cover secured to the frame to define an enclosure.

12. An electronic apparatus according to claim 11 wherein the side faces of each wall are generally parallel.

13. An electronic apparatus according to claim 12 wherein the tapered end portion of each wall comprises a pair of elongate end faces symmetrical about a plane generally parallel to and equidistant between the side faces of a respective wall, and wherein each end face in the pair abuts an edge of the corresponding end face of the pair and also abuts an edge of a respective side face.

14. An electronic apparatus according to claim 13 wherein the abutting end faces form an angle of between about 5 degrees and about 45 degrees.

15. An electronic apparatus according to claim 12 wherein the solder is substantially contained within the cavity.

16. An electronic apparatus according to claim 12 wherein each wall is formed from material having a higher melting point than a melting point of the solder.

17. An electronic apparatus according to claim 12 wherein the cover and each wall are formed from metalized polymeric material.

18. An electronic apparatus according to claim 12 wherein the electronic apparatus is a radiotelephone.

19. An electronic apparatus, comprising:

an electronic substrate; and

an electromagnetic shielding apparatus secured to the electronic substrate, comprising;

an electrically conductive frame, comprising;

a plurality of elongate metal walls;

wherein each wall includes a pair of opposing, generally parallel side faces terminating at a tapered end portion;

wherein each tapered end portion is secured to a respective conductive mounting pad on the electronic substrate via solder;

wherein the tapered end portion of each wall comprises a pair of elongate end faces symmetrical about a plane generally parallel to and equidistant between the side faces of a respective wall;

wherein each end face in the pair abuts an edge of the corresponding end face of the pair and also abuts an edge of a respective side face to define a pair of cavities with respect to a respective conductive mounting pad; and

wherein each cavity is configured to contain solder therewithin; and

an electrically conductive cover secured to the frame to define an enclosure.

20. An electronic apparatus according to claim 19 wherein the abutting end faces form an angle of between about 5 degrees and about 45 degrees.

21. An electromagnetic shielding apparatus according to claim 19 wherein each wall is formed from material having a higher melting point than a melting point of the solder.

22. An electronic apparatus according to claim 19 wherein solder is substantially contained within a respective cavity.

23. An electronic apparatus according to claim 19 wherein the electronic apparatus is a radiotelephone.

24. An electronic substrate, comprising:

an elongate conductive mounting pad disposed on the electronic substrate; and

an elongate, electrically conductive wall secured to the conductive mounting pad, comprising;

a pair of opposing, generally parallel side faces terminating at a tapered end portion, wherein a cross-sectional dimension of the tapered end portion decreases in a direction towards the conductive mounting pad to define a cavity with respect to the conductive mounting pad, wherein the tapered end portion comprises a pair of elongate, planar end faces symmetrical about a plane generally parallel to and equidistant between the side faces, wherein each planar end face abuts an edge of the corresponding planar end face of the pair and also abuts an edge of a respective side face, and wherein the tapered end portion is secured to the conductive mounting pad via solder disposed within the cavity.

25. An electronic substrate according to claim 24 wherein the abutting planar end faces form an angle of between about 5 degrees and about 45 degrees.

26. An electronic substrate according to claim 25 wherein the wall is formed from material having a higher melting point than a melting point of the solder.

27. An electronic substrate according to claim 26 wherein the wall is formed from metalized polymeric material.

28. An electronic substrate according to claim 24 wherein the solder is substantially contained within the cavity.