WO1998024285A1

WO1998024285A1 - Shield can for structural enhancement

Info

Publication number: WO1998024285A1
Application number: PCT/US1997/021749
Authority: WO
Inventors: Gregory S. Patterson
Original assignee: Ericsson Inc.
Priority date: 1996-11-27
Filing date: 1997-11-24
Publication date: 1998-06-04
Also published as: AU5461398A

Abstract

A shield can (12) for an electronic device (e.g., mobile phone) is provided that includes one or more protruding screw bosses (16). The screw bosses (16) are attached to a section of the electronic device where a bending, twisting or similar force is likely to occur. Consequently, the screw bosses transfer the rigidity and stiffness characteristics of the shield can (12) to the vulnerable section and thereby increase the overall structural integrity of the electronic device without increasing its overall size.

Description

SHIELD CAN FOR STRUCTURAL ENHANCEMENT

BACKGROUND OF THE INVENTION

Technical Field of the Invention The present invention relates generally to the communications manufacturing field and, in particular, to a shield can for use in improving the structural integrity of an electronic device.

Description of Related Art Shield cans have long been used to provide radio frequency (RF) shielding for electronic components. For example, shield cans have been used to electrically isolate RF components on printed circuit boards (PCBs) in mobile phones and similar electronic devices. Shield cans can be manufactured in many different geometries and configurations that conform to the enclosures in which they are contained. Due to their box- like shapes and metal construction, shield cans are inherently stiff and form a rigid cover over the areas that they enclose . For many electronic devices (e.g., mobile phones), a typical manufacturing goal is to produce smaller, lighter and less expensive products. Consequently, plastic housings for mobile phones are often preferred because of their relatively low cost, light weight, and aesthetic appearance. However, the structural integrity of such products is reduced significantly, whenever plastic housings are substituted for metal enclosures. In order to offset this reduction in strength, manufacturers often incorporate "ribs" or other such features into the plastic housings to increase their overall stiffness, but in order to be effective, these additional features increase the overall size of the product . SUMMARY OF THE INVENTION Accordingly, a shield can for an electronic device

(e.g., mobile phone) is provided that includes one or more protruding screw bosses . The screw bosses are attached to a section of the electronic device where a bending, twisting or similar force is likely to occur. Consequently, the screw bosses transfer the rigidity and stiffness characteristics of the shield can to the vulnerable section and thereby increase the overall structural integrity of the electronic device without increasing its overall size. BRIEF DESCRIPTION OF THE DRAWINGS A more complete understanding of the method and apparatus of the present invention may be had by reference to the following detailed description when taken in conjunction with the accompanying drawings wherein:

FIGURE 1 is a cutaway perspective view of a section of a mobile phone housing, which includes a shield can that is structured and arranged in accordance with a preferred embodiment of the present invention; and

FIGURE 2 is an isometric detailed view of the shield can shown in FIGURE 1.

DETAILED DESCRIPTION OF THE DRAWINGS

The preferred embodiment of the present invention and its advantages are best understood by referring to FIGURES 1-2 of the drawings, like numerals being used for like and corresponding parts of the various drawings.

FIGURE 1 is a cutaway perspective view of a section of a mobile phone housing 10, which includes a shield can 12 that is structured and arranged in accordance with a preferred embodiment of the present invention. For this embodiment, shield can 12 is preferably made of an aluminum alloy metal. However, any conventional metal shield material may be used for shield can 12. Alternatively, shield can 12 can be made from a partly conductive material, such as, for example, a "cast" metal material or a metallized plastic material.

FIGURE 2 is an isometric detailed view of shield can 12 shown in FIGURE 1. Referring to FIGURES 1 and 2, shield can 12 is arranged to enclose a predetermined surface segment of a PCB 14. Shield can 12 includes a pair of bosses 16 that protrude from opposite ends 22 of one side 24 of the shield can. For the embodiment shown in FIGURES 1 and 2, each of bosses 16 is made from the same material as shield can 12, and is arranged to protrude in a direction that is substantially perpendicular to the planar surface of side 24 of shield can 12. Preferably, each of bosses 16 includes a hole 18 for receiving a screw 20. Consequently, each of a pair of screws 20 can be inserted through a respective hole 18 in a boss 16, and a corresponding hole (not explicitly shown) in PCB 14 and housing 10, and tightened to secure shield can 12 to housing 10. The stiffness and rigidity characteristics of shield can 12 are thus extended by bosses 18 to the area 15 of PCB 14 and housing 10. Preferably, bosses 16 extend from the shield can in a direction that is substantially perpendicular to a bending motion that can be experienced at area 15. For example, for a force experienced in the direction of vector 7, a bending force will be experienced along a line that extends through a portion of area 15 and between bosses 16. Therefore, in accordance with the present inventive concept, the addition of one or more protruding bosses to an RF shield can extends the rigidity and stiffness of the shield can to an area of the mobile phone where a bending force can be expected to occur, which significantly improves the overall structural integrity of the mobile phone . For another embodiment of the present invention, holes 18 may or may not be included in bosses 16, and/or each boss can be soldered to PCB 14 and thereby secured to the PCB of the mobile phone. Alternatively, each boss 16 may or may not include holes and is thus unsecured, as such, to the mobile phone. However, the placement of housing 10 over the bosses will function to secure the shield can to the phone and also impart the added stiffness and rigidity of the shield can to the expected bending area 15 of the phone.

Structural variations to bosses 16 can be made that are still within the scope of the invention. For example, the preferred embodiment utilizes a pair of bosses that are arranged to extend in a direction substantially perpendicular to side surface 24. However, the bosses also can be fabricated to extend from the shield can in a direction that is not perpendicular to side surface 24. For maximum rigidity and stiffness, the bosses should extend perpendicular to the direction of an expected bending motion, but a smaller angle can be attained (e.g., 45 degrees) if a reduced amount of rigidity and stiffness is acceptable. Moreover, it is also within the scope of the present invention to use only one boss (or many bosses) to extend the stiffness and rigidity of a shield can to an area that is beyond the direct confines of the shield can. Also, although the term "boss" is used herein to describe the extension 16 attached to a side of a shield can, it is used for illustrative purposes only, and any appropriate element that is shaped similar to the bosses shown and can transfer the stiffness and rigidity characteristics of the shield can to a different location is covered by the present invention. Although a preferred embodiment of the method and apparatus of the present invention has been illustrated in the accompanying Drawings and described in the foregoing Detailed Description, it will be understood that the invention is not limited to the embodiments disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the spirit of the invention as set forth and defined by the following claims .

Claims

WHAT IS CLAIMED IS:

1. An apparatus for use in increasing structural integrity of a communications device, comprising: a multi-sided enclosure formed from at least a conductive material and enclosing a first predetermined area of said communications device; and at least one means attached to an external side of said multi-sided enclosure and a second predetermined area of said communications device, for stiffening said second predetermined area.

2. The apparatus of Claim 1, wherein said multi - sided enclosure comprises a shield can.

3. The apparatus of Claim 1, wherein said at least one means comprises a screw boss.

4. The apparatus of Claim 1, wherein said at least one means is arranged substantially perpendicular to said external side.

5. The apparatus of Claim 1, wherein said at least one means is fixedly attached to said external side.

6. The apparatus of Claim 1, wherein said at least one means is formed from said external side.

7. The apparatus of Claim 1, wherein said multi- sided enclosure is formed from at least a partly conductive material.

8. The apparatus of Claim 1, wherein a portion of said multi-sided enclosure is soldered to a portion of said first predetermined area, and said at least one means is for strengthening and structurally supporting said multi-sided enclosure.

9. The apparatus of Claim 1, wherein said at least one means is attached to said second predetermined area with solder.

10. The apparatus of Claim 1, wherein said at least one means is attached to said second predetermined area with a screw.