Patent Application
20100309629
1. Technical Field
The present disclosure relates to a metal board defining meshes therein.
2. Description of Related Art
An electronic device usually includes a metal shell. A depressed portion may be formed on the shell via punch. The punching process is actually a process that a corresponding part of the shell for forming the depressed portion is extended to become thin and so as to enlarge the area of the part, which may cause the part to be ruptured.
Referring to
In the present embodiment, when the plurality of electronic elements 10 work, a maximum frequency of electromagnetic waves generated by the plurality of electronic elements 10 is no more than 2 gigahertz, in other words, a minimum wavelength of the electromagnetic waves generated by the plurality of electronic elements 10 is no less than 150 millimeters (mm).
The shell 20 includes a base 30 for receiving the plurality of electronic elements 10, and a vented board 40 covering on the base 30.
The base 30 may define a plurality of holes 31 therein, for helping dissipating heat. A diameter of each hole 31 is no more than 5 mm, one thirtieth of the minimum wavelength, so as to prevent the electromagnetic waves generated by the plurality of electronic elements 10 from escaping outside the shell 20.
The vented board 40 may be ferric. For example, the vented board 40 may be made from double-cold-rolled plate. The double-cold-rolled plate may be a double-cold-rolled plate (DR-7 plate), which has DR-7 of hardness, 520 newtons per square millimeters (N/mm2) of yield stress, and 11% of percentage of elongation. Alternatively, the double-cold-rolled plate may be a malei plate (DR-9 mL620 plate), which has DR-9 of hardness, 620 N/mm2 of yield stress, and 7% of percentage of elongation. The double-cold-rolled plate may also be an ordinary tin plate (DR-9 TH620 plate), which has DR-9 of hardness, 620 N/mm2 of yield stress, and 7% of percentage of elongation. In the present embodiment, the DR-9 TH620 plate is selected. Although the percentage of elongation of the DR-9 TH620 plate is less than other kinds of double-cold-rolled plates above mentioned, using the DR-9 TH620 plate can save 5% in material cost comparing to using the DR-9 mL620 plate, and 20% comparing to using the DR-7 plate. In other embodiments, other metal material, such as aluminium alloy or magnesium alloy, may be selected for making the vented board 40.
Referring to
Step S1: provide a flat plate 40a (see
Step S2: punch holes to form a mesh area 22a in the plate 40a, wherein the mesh area 22a defines a plurality of hole units 23a. Referring to
Step S3: punch a recessed portion 21 on the plate 40a, to extend and/or bend the mesh area 22a to form a side wall 22 of the recessed portion 21. The vented board 40 is done.
After the step S3, some of the first and second borders 24a and 25a of the hole units 23a of the mesh area 22a are extended to be deformed, to make the mesh area 22a form the side wall 22, and an area of the mesh area 22a increases 20% because of being extended while a thickness of the mesh area 22a remains constant. It is noted that the diameter of the circumcircle of each hole 26a is designed to be about 4 mm is to make sure that a maximum width of the opening of each hole 26a will be no more than 5 mm, one thirtieth of the minimum wavelength of the electromagnetic waves generated by the plurality of electronic elements 10, when the 20% area increasing of the mesh area 22 is achieved after punching. Therefore, the electromagnetic waves can be prevented from escaping outside the shell 20 through the holes 26a. In other embodiments, the diameter of the circumcircle of each hole 26a may be adjusted according to a minimum wavelength of the electromagnetic waves generated by the plurality of electronic elements 10 received in the shell 20 and a desire area increasing extent of the mesh area 22 after the step S3.
Accordingly, the area of the mesh area 22a can be extended to increase at least 20%, which compensates for the poor extensibility of the material and thereby solving the rupturing problem when a plate is extended.
Referring to
In sum, in the present disclosure, the borders 24a, 25a, and 24b of the mesh areas 22a and 22b are designed to be curve-shaped. When the mesh area 22a or 22b is extended, the borders 24a, 25a, and 24b are extended to tend to be straight, so as to enlarge a size of each hole 26a or 26b. The area of the mesh area 22a or 22b is increased via extending the mesh area 22a or 22b along any direction parallel with the mesh area 22a or 22b, while the thickness of the mesh area 22a or 22b remains constant. Accordingly, it can be seen that the present disclosure substantively employs an innovative way, in which the curve-shaped borders are extended to tend to be straight, to enlarge an area of the material, instead of extending the material to become thin and so as to enlarge the area of the material. Therefore, the rupturing problem caused by thinning the material can be avoided. Furthermore, it can be seen that the method disclosed by the present disclosure fits for multifarious metal materials.
In other embodiments, each hole in the mesh area may be five-pointed-star-shaped, six-pointed-star-shaped, and so on.
In other embodiments, the vented board 40 may be integrally formed with the base 30.
It is to be understood, however, that even though numerous characteristics and advantages of the disclosure have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
| Number | Date | Country | Kind |
|---|---|---|---|
| 200910302886.4 | Jun 2009 | CN | national |
