Electricity: conductors and insulators – Boxes and housings – Hermetic sealed envelope type
Patent
1996-08-29
1999-05-25
Kincaid, Kristine L.
Electricity: conductors and insulators
Boxes and housings
Hermetic sealed envelope type
174 17CT, H05K 502
Patent
active
059071257
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
The present invention relates to a device for providing environmental protection around electrical connectors, components or circuitry.
In particular, the invention provides a device comprising a network termination module that preferably contains a so-called maintenance termination unit or MTU. Such units are often provided in a telecommunications network between that part which is the responsibility of the telephone company and that part which is the responsibility of the subscriber. The module serves as a demarcation point and allows remotely-activated disconnection and testing.
Such modules generally need to provide protection from the environment in order that they may be positioned in unfavourable locations for example on an external wall of a building. Such environmental protection can prevent moisture or other contaminants from damaging electrical connectors, components and circuitry.
SUMMARY OF THE INVENTION
According to a first aspect of the invention, there is provided a device for environmental protection of an electrical component on a mount, which comprises: substantially closed housing; respect to the first housing part; and housing part; put the sealing material under compression.
The fact that the sealing material may be put under compression by moving the mount with respect to the first housing part has an advantage in that mere movement of the mount may improve the sealing characteristics of the sealing material or it may transform the sealing material from a state in which it can not form an effective seal into a state in which it can form an effective seal. This is particularly applicable to embodiments of the invention which use gel or a gel-like substance as the sealing material, since such materials often perform best when they are placed under compression. Such compression may, advantageously, be applied to the sealing material in a way which accommodates creepage due to temperature fluctuations or due to the applied compression itself, while keeping the sealing material under compression. For example, one or more resilently biassing means, e.g. springs, may be provided, or such resilient biassing may be provided by the material of the housing or by the mount for the electrical component.
Preferably the movement of the mount with respect to the first housing part causes displacement of sealing material to a position where it can form a seal between the first and second housing parts. This has an advantage in that the formation of the seal between the first and second housing parts may occur substantially automatically upon movement of the mount with respect to the first housing part. This may, for example, enable the sealing material to be retained in a position in which it is protected from damage or contamination while a technician works on the mount and only to be displaced into a sealing position when the device is re-closed. More preferably, the displacement of the sealing material comprises formation of a bead of sealing material between a wall of the first housing part and the mount. Most preferably, the sealing material is displaced such that a substantially continuous bead of material is formed around the mount, between the mount and a wall of the first housing part which may be contacted by the second housing part to form a continuous seal between the first and second housing parts.
The mount for an electrical component preferably comprises a circuit board, especially a printed circuit board.
According to a preferred embodiment of the invention, the device further comprises one or more supports for the mount, which project from the said surface of the first housing part, the supports being constructed to allow the mount to be moved with respect to, preferably towards, and more preferably towards and away from, the said surface of the first housing part to put the sealing material under compression. The support or supports may, for example, advantageously prevent lateral movement (including rotation) of the mount with respect to the first ho
REFERENCES:
patent: 4505403 (1985-03-01), Bowden, Jr. et al.
patent: 4694555 (1987-09-01), Russell et al.
patent: 4718678 (1988-01-01), Vansant
patent: 4770641 (1988-09-01), Rowlette
patent: 5155660 (1992-10-01), Yamada et al.
patent: 5206460 (1993-04-01), Yang
patent: 5239446 (1993-08-01), Matsumura et al.
patent: 5268814 (1993-12-01), Yakubowski
patent: 5317921 (1994-06-01), Kremidas
patent: 5334799 (1994-08-01), Naito et al.
patent: 5386342 (1995-01-01), Rostoker
patent: 5536972 (1996-07-01), Kato
Buekers Valere
Delvaux Roger
Demesmaeker Marc
Burkard Herbert G.
Kincaid Kristine L.
N.V. Raychem S.A.
Reichard Dean A.
LandOfFree
Environmental protection does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Environmental protection, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Environmental protection will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-402297