PCI I/O bracket retainer

Details PCI I/O bracket retainer PCI I/O bracket retainer

1999-04-30

2001-10-30

Cuomo, Peter M. (Department: 3636)

Supports: cabinet structure

For particular electrical device or component

Housing for computer or computer related equipment

C312S265600, C361S801000, C361S825000, C403S353000

Reexamination Certificate

active

06309037

ABSTRACT:

BACKGROUND OF THE INVENTION
The invention relates to mounting of an I/O bracket in a metal chassis of a computer system, and more specifically to a low EMI leakage solution to mounting an I/O bracket. Today's computer systems are required to connect to multiple peripheral devices such as external storage and network devices. Conductive pathways supported by input/output (I/O) panels in the computer chassis provide a means through which the input and output signals of the components in the chassis of the computer can communicate with peripheral devices external to the chassis.
Referring to
FIGS. 1A and 1B
show a partial view of a metal chassis
110
before insertion of an I/O panel
112
or I/O bracket
112
into the I/O frame
114
of the metal chassis
110
. Typically for each I/O card, there is a corresponding opening in the rear of the metal chassis. It is well known that electronic components housed in the computer chassis are capable of emitting electromagnetic radiation and standards have been established for limiting such emissions. Openings in the metal chassis and leakage resulting from seams formed between two metal surfaces in the chassis can present particularly difficult problems with respect to such electromagnetic radiation.
Designs are typically made to minimize openings in the metal chassis and leakage due to seams. In the embodiment shown in
FIG. 1A
the openings
116
in the I/O frame are closed and the I/O panel
112
is secured to the I/O frame
114
by screwing the I/O panel
112
to the I/O frame
114
. Although the implementation and assembly required by screwing the I/O panel to the I/O frame is simple, typically it does not provide a good EMI seal and the EMI rating of the closure required by
FIG. 1A
is not acceptable for all applications. The problem with the closure required by
FIG. 1A
, is that the differences in planarity between the metal I/O bracket retainer
118
, the I/O frame
114
and the metal I/O panel
112
typically causes a seam to form along the edges of the I/O panel, resulting in EMI leakage. The solution of precisely machining the planarity of the parts so that no EMI leakage occurs is cost prohibitive. An alternative solution is to add a gasket between the metal I/O bracket retainer and the metal I/O panel.
In a second alternative embodiment, a gasketing layer
120
is positioned between the I/O bracket retainer
118
and the I/O panel of the metal chassis.
FIG. 1B
shows a partial view of a metal computer chassis before insertion of the gasketing layer
120
and I/O panel
112
into the I/O frame
114
. Although the metal chassis
110
is typically comprised of sheet metal, typically the gasketing layer
120
shown in
FIG. 1B
is comprised of a stainless steel material. Conventionally the gasketing layer
120
is a thin layer of stainless steel, that typically has a thickness in the range of 0.15 to 0.3 mm. The gasketing layer
120
is typically dimpled so that it is nonplanar and conforms to the surfaces of the I/O bracket retainer
118
and the I/O panel
112
. The gasketing layer
120
helps to eliminate any differences in planarity between the surface of the I/O bracket retainer
118
and I/O panel
112
by rubbing against the surfaces of the I/O bracket retainer and I/O panel sheet metal to ensure good contact is made, thus helping to eliminate any seams where EMI radiation leakage could occur.
Although the embodiment shown in
FIG. 1B
helps prevent EMI leakage, the configuration is more difficult to assemble than the embodiment shown in FIG.
1
A. The gasket layering
120
must be carefully aligned so that the openings
116
of the I/O frame
114
coincide with the openings of the I/O panel and further that the screw hole for the gasketing layer are aligned to the corresponding screw holes of the I/O bracket and I/O frame. A further concern with related to the embodiment shown in
FIG. 1B
is design flexibility. Gasketing layers may need to be customized to fit a non-standard I/O opening potentially increasing computer system costs.
An I/O bracket retainer which is easy to assemble, takes minimal space and which provides design flexibility and excellent EMI shielding is needed.
SUMMARY OF THE INVENTION
The present invention provides an I/O bracket retainer which is easy to assemble, takes minimal space and which provides design flexibility and excellent EMI shielding. The I/O bracket retainer is preferably a rectangular structure that includes first, second, third and fourth sidewalls, wherein the first sidewall is opposite to the second sidewall and the third sidewall is opposite to the four sidewall. A front panel or section of the I/O bracket retainer is preferably positioned to be generally orthogonal to the first, second, third and fourth sidewalls of the I/O bracket retainer structure. The front panel of the I/O bracket retainer is designed for receiving and securing an I/O panel and includes an opening for receiving the I/O panel. The back panel of the I/O bracket retainer, opposite to the front panel of the I/O panel, is preferably left open to facilitate electrical connection from peripheral devices to the I/O panel.
The I/O bracket retainer of the present invention is preferably a unitary structure that provides excellent EMI shielding without the requirement of an additional gasket layer. EMI leakage is minimized by providing an I/O bracket retainer surface that conforms to the surface of the I/O bracket retainer and I/O panel, thus minimizing seams formed due to small differences in the planarities of the I/O bracket retainer and I/O panel. EMI leakage is further reduced by providing firm contact between the surfaces of the I/O bracket retainer and I/O panel to minimize seam formation between these parts.
In the preferred embodiment of the present invention, the I/O bracket retainer includes at least a first positioning tab and at least a first spring finger. The positioning tab and spring finger typically extend from a sidewall of the rectangular structure to the front panel of the I/O bracket retainer. Securing the position of the I/O panel so that it is fixed to prevent motion in the direction towards the back of the I/O bracket is performed primarily by the combination of the spring fingers and the positioning tabs. The I/O panel is typically slid into position so that it is sandwiched or positioned between the first spring member and the positioning tab of the I/O bracket. The spring finger provides an inward force directed towards the back of the I/O bracket opening and thus the metal chassis, while the positioning tab prevents the I/O panel movement from further movement in the direction towards the back of the I/O bracket retainer.
In the preferred embodiment, the I/O bracket retainer includes an I/O frame tab extending from a first sidewall of the I/O bracket retainer and a chassis attachment tab extending from a second sidewall of the I/O bracket retainer, The I/O frame tab fits into an opening on the I/O frame of the metal chassis while the chassis attachment tab is attached to the I/O frame of the metal chassis, typically using a rivet. The combination of the I/O frame tab and chassis attachment tab secures the I/O panel in the plane generally parallel to the front face of the I/O bracket retainer while the combination of the spring finger member and positioning tab prevent movement of the I/O panel in the direction towards the back opening of the I/O bracket retainer. The combination of these elements of I/O bracket retainer acts to provide firm contact and secure positioning between the surfaces of the I/O bracket retainer, I/O panel and the metal chassis to minimize seam formation between these parts.
The I/O bracket retainer is designed to be attached to a metal chassis and I/O panel that are both comprised of a sheet metal material, a material that has limited deformation qualities. The I/O bracket retainer is preferably formed from stainless steel material that will deflect or bend, yet will not set or permanently deform for the force typically applied to the I/O bracket retainer

Affiliated with

Also associated with

Rating

PCI I/O bracket retainer does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with PCI I/O bracket retainer, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and PCI I/O bracket retainer will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2577213