Electricity: conductors and insulators – Anti-inductive structures – Conductor transposition
Reexamination Certificate
1999-02-25
2001-03-06
Reichard, Dean A. (Department: 2831)
Electricity: conductors and insulators
Anti-inductive structures
Conductor transposition
C174S051000
Reexamination Certificate
active
06198040
ABSTRACT:
The present invention relates to a cover apparatus and method for covering some or all of one or more openings provided for accessing components of electronic equipment and in particular to a grounded cover such as for avoiding or reducing electromagnetic interference (EMI) and/or electrostatic discharge (ESD).
BACKGROUND INFORMATION
A number of electronic devices are configured with openings to permit ready access to some of the components of the device (e.g. without requiring opening the entire chassis of the electronic device). In many situations, ready access involves providing access through a wall or panel which is typically exposed, such as a front panel. For example, many computers, network devices (such as routers, switches, bridges and the like) and other equipment provide one or more PCMCIA openings or slots (i.e. openings configured to receive cards in accordance with the PC Card Standard promulgated by Personal Computer Memory Card International Association e.g. at http://www.pc-card.com/pccardstandard.htm) for receiving and removing components such as disk drives or other storage devices or media, modems, network connection cards and the like. While providing such openings is convenient when it is desired to insert or remove components or media, non-covered (or easily uncovered) openings can present a security risk (e.g. a risk of theft or other unauthorized removal, tampering and the like) particularly when the accessible components are relatively expensive. Furthermore, in some devices a function of the accessible component may be critical to operation of a larger system, such as a computer network, Internet, telephone or other communication system and the like. Thus, the ease of accessibility afforded by openings for components also presents the risk that unauthorized or unintentional removal or manipulation of a component may cause catastrophic losses of a larger system such as disabling an entire telephone or computer network. Accordingly, it would be useful to provide a system which preserves the convenience of access to components, especially front panel access (without opening an entire chassis), while avoiding unauthorized or inadvertent removal or manipulation of components.
Many electronic devices such as computers, network or telephone equipment and the like are designed in a fashion to avoid undesirably high levels of electromagnetic radiation, extending beyond the chassis of the device which can result in undesirable effects on adjacent electronic equipment including so-called electromagnetic interference (EMI). Indeed, several standards for maximum allowable levels of EMI have been established such as the Network Equipment Building Standards (available from Bellcore). Some designs for avoiding EMI involve using a substantially conductive, preferably grounded, chassis substantially surrounding the electronic equipment forming, substantially, a Faraday shell. Provision of openings in the chassis, such as openings as described above, create a risk of breaching the Faraday shell allowing an undesirable increase in potential EMI. One approach which has been used in this regard involves constructing a pocket (With suitable covers or connectors) for receiving the removable component or medium, made of a conductive material in electrical continuity with the chassis. This approach can be somewhat expensive and often requires utilization of substantial space within the chassis, which may be at a premium, particularly when the chassis itself must conform to certain standard sizes or form factors such a so-called rU form factors. Accordingly, it would be useful to provide a system for avoiding or reducing EMI from component-access openings with relatively low cost and space requirements.
Many electronic components, including those designed to be accessible without fully opening a chassis, and/or which are front-panel accessible, can be susceptible to voltage surges such as those that may be caused by electrostatic discharge (ESD) including components such as high density disk drives. In such susceptible components, ESD or other voltage surges can lead to malfunction and/or permanent damage to the component. Moreover, when the component is critical to functioning of a larger system such as a computer network or telephone system, ESD or other voltage surges can lead to catastrophic loss of function of an entire system. A number of standards setting acceptable levels of tolerable ESD have been promulgated, including, e.g., NIBS standards. Accordingly, it would be useful to provide a system which tends to ground or dissipate, in a relatively benign fashion, ESD or other voltage surges such as may otherwise occur when personnel touch or manipulate an accessible component in an electronic device.
SUMMARY OF THE INVENTION
The present invention, in at least one aspect, provides a substantially conductive cover for a PCMCIA slot or other opening which is grounded to the front panel or chassis. Preferably the cover can be moved from a covering position to an uncovering position while substantially maintaining a conductive path between the cover and the chassis or front panel. In one embodiment, the cover is hinged so that the cover remains physically (pivotally) coupled to the front panel even in the open position. In one case, conductive washers, bushings or similar components are provided in a system maintaining a conductive path to the faceplate during and after pivoting of a hinged cover. Preferably the cover is normally maintained in a closed position by a fastener configured such that opening the cover requires the use of a tool, e.g. to avoid inadvertent or casual opening. In one embodiment the cover is configured for automatic, preferably gravity-forced, closing of the cover. Preferably the fully closed cover is substantially sealed to the faceplate to form a substantially continuous conductive region, reducing or preventing EMI.
REFERENCES:
patent: 3140344 (1964-07-01), Slater et al.
patent: 3204807 (1965-09-01), Ramsing
patent: 3808509 (1974-04-01), Frazier
patent: 3956573 (1976-05-01), Myers et al.
patent: 3966073 (1976-06-01), Geisel
patent: 3971614 (1976-07-01), Paoli et al.
patent: 4036396 (1977-07-01), Kennedy et al.
patent: 4865556 (1989-09-01), Campbell et al.
patent: 5317105 (1994-05-01), Weber
patent: 5397857 (1995-03-01), Farquhar et al.
patent: 5677511 (1997-10-01), Taylor et al.
patent: 5682299 (1997-10-01), Kunert
patent: 5743752 (1998-04-01), Massebeuf
patent: 5877450 (1999-03-01), Quin
patent: 5955702 (1999-09-01), Grossman et al.
Desousa Carl
Goyette Robert
Cisco Technology Inc.
Reichard Dean A.
Sheridan & Ross P.C.
LandOfFree
Grounding cover method and apparatus for accessible... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Grounding cover method and apparatus for accessible..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Grounding cover method and apparatus for accessible... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2437310