Patent Application
20160035518
The invention relates to arc-resistant compartments for use in the power generation/distribution industry such as a circuit breaker or a current limiter compartment and, more particularly, to a door of the compartment having vent flap structure for venting the compartment and sealing the compartment during an arcing event.
Compartments for use in the power generation/distribution industry such as a circuit breaker or current limiter compartment typically must be arc-resistant. Venting of these compartments is important to minimize the temperature rise inside the compartment. Conventionally, an opening is provided in a non-door portion of the compartment to permit air flow into the compartment. However, these openings are limited due to the configuration of the compartment and thus may not introduce adequate air flow into the compartment.
Thus, there is a need to provide a door for an arc-resistant compartment that includes vent flap structure over an opening in the door. The vent flap structure is normally opened to permit air flow into the compartment and, in the event of an arcing event, will automatically close the opening.
An object of an embodiment is to fulfill the need referred to above. In accordance with the principles of an embodiment, this objective is obtained by providing a door for an arc-resistant compartment. The door includes surfaces defining at least one opening through the door, and flap structure. The flap structure includes a flap member coupled to the door and movable between an opened position permitting air to pass through the opening, and a closed position covering the opening. Spring structure is engaged with the flap member and is constructed and arranged to bias the flap member to the closed position. Handle structure is coupled to the flap member and extends through the door for moving the flap member to the opened position against the bias of the spring structure. Retaining structure is constructed and arranged to provide a retaining force on the flap member to retain the flap member in the open position, against the bias of the spring structure. The retaining structure is constructed and arranged such that during an arcing event in the compartment, pressure within the compartment together with the bias of the spring structure overcomes the retaining force to automatically move the flap member to the closed position.
In accordance with another aspect of an embodiment, a method provides for venting an arc-resistant compartment having a door for accessing an interior of the compartment. The method provides at least one opening through the door of the compartment. A flap member is mounted to the door in the interior of the compartment so that the flap member is movable between an opened position permitting air to pass through the opening, and a closed position covering the opening. The flap member is moved, against a biasing force, to be in the opened position. A retaining force is provided, against the biasing force, to retain flap member in the opened position. During an arcing event in the compartment, resulting pressure in the interior together with the biasing force automatically moves the flap member, against the retaining force, to the closed position.
Other objects, features and characteristics of the present invention, as well as the methods of operation and the functions of the related elements of the structure, the combination of parts and economics of manufacture will become more apparent upon consideration of the following detailed description and appended claims with reference to the accompanying drawings, all of which form a part of this specification.
The invention will be better understood from the following detailed description of the preferred embodiments thereof, taken in conjunction with the accompanying drawings, wherein like reference numerals refer to like parts, in which:
With reference to
As best shown in
With reference to
Once the flap member 20 is in the opened position, retaining structure, generally indicated at 32, is constructed and arranged to provide a retaining force on the flap member 20 to retain the flap member 20 in the open position, against the bias of the spring structure 22. In the embodiment, the retaining structure is a conventional ball catch structure comprising a strike member 34 fixed to a portion of the handle structure 28 and catch member 36 fixed to a bracket 38 coupled to the door 12. The catch member 36 includes a pair of balls 40 that engage the strike member 34. Thus, in the embodiment, both the strike member 34 and catch member 36 are disposed on the outside of the door 12. When the flap member 20 is moved to the opened position, the strike member 34 frictionally engages the balls 40 of the catch member 36 to retain the flap member 20 in the opened position. During an arcing event in the compartment 10, pressure within the compartment together with the bias of the spring structure 22 overcomes the retaining (friction) force of the retaining structure 32 to automatically move the flap member 20 to the closed position to reduce gas leakage from the compartment 10 during the arcing event.
Upon closing of the flap member 20 during the arcing event, it is important to prevent bounce back of the flap member 20 so as to reduce gas leakage. Thus, with reference to
The door 12 with the opening(s) 16 minimize the temperature rise in the arc-resistant compartment 10, while the fast, spring assisted closing of the flap member 20 prevents gas leakage from the compartment during an arcing event.
The foregoing preferred embodiments have been shown and described for the purposes of illustrating the structural and functional principles of the present invention, as well as illustrating the methods of employing the preferred embodiments and are subject to change without departing from such principles. Therefore, this invention includes all modifications encompassed within the spirit of the following claims.
