Stoves and furnaces – Fireplaces or accessories – Fluid fuel
Reexamination Certificate
2000-06-09
2002-10-15
Bennett, Henry (Department: 3743)
Stoves and furnaces
Fireplaces or accessories
Fluid fuel
C126S08500R, C126S30700R
Reexamination Certificate
active
06463926
ABSTRACT:
BACKGROUND OF THE INVENTION
(1) Field of the Invention
The present invention pertains to a direct vent gas fireplace that combines in a self-contained supporting outer shell beneficial features such as a directional flue pipe, a concealed exhaust opening in the fireplace firebox and a supply of vent air adjacent to the bottom of the fireplace firebox without significantly detracting from the heat exchange capabilities of the fireplace.
(2) Description of Related Art
Direct vent gas fireplaces typically include a firebox surrounding a heat chamber of the fireplace, where the firebox itself is surrounded by an outer shell. The firebox is typically constructed of left and right metal panels, top and bottom metal panels and a back panel that are connected together in a box-like configuration. The front of the firebox is left open providing access into the heat chamber of the firebox. The heat chamber contains a grate supporting a gas burner assembly which is usually concealed by gas logs. An exhaust opening is provided through the back panel of the firebox toward the top of the heat chamber to exhaust combustion fumes from the heat chamber.
The panels of the firebox are usually supported by metal walls of the surrounding outer shell of the fireplace. The outer shell is typically constructed of left and right side walls and a back wall that are spaced outwardly from the side panels and back panel of the firebox, together with opposite top and bottom walls that are spaced from the top and bottom panels of the firebox. Apart from the front access opening of the firebox, the firebox is usually completely enclosed by the outer shell walls and is supported in the outer shell with there being a void or spacing between the panels of the firebox and the walls of the outer shell. The spacing functions as a heat exchange volume surrounding the firebox in the outer shell. Vent panels are usually provided on the fireplace above and below the access opening to the firebox. An electric blower is positioned in the heat exchange volume where it will draw in ambient room air through the bottom vent of the fireplace and force a flow of air through the heat exchange volume and around the firebox and finally out through the top vent panel of the fireplace.
As air is cycled around the firebox panels by the blower, the heat of combustion in the heat chamber of the firebox is transferred through the firebox panels to the air cycled through the heat exchange volume. In this manner, the ability of the fireplace to heat the ambient air of the room in which the fireplace is positioned is optimized. Understandably, by increasing the interior surface area of the firebox panels that are directly subjected to the heat of gas combustion in the firebox heat chamber and by increasing the exterior surface area of the firebox panels that transfer the heat of combustion to the ambient room air cycled around the firebox, the ability of the fireplace to heat ambient room air is enhanced.
Over the years several structural features have been added to the typical gas fireplace to improve their combustion and versatility. For example, direct vent gas fireplaces have been developed that provide a supply of venting air from outside the building containing the fireplace directly to the firebox heat chamber. Direct vented air is typically more rich with oxygen than the ambient air of the room in which the fireplace is positioned and therefore enhances the combustion of the gas fireplace. The direct vented air of some fireplaces is provided through an air pipe that is concentric with and surrounds an exhaust pipe that is exhausting combustion fumes from the fireplace heat chamber to the building exterior. However, in some prior art direct vent gas fireplaces a system of conduits channels the vent air through the heat exchange volume between the firebox and the outer shell of the fireplace to inlet ports that supply the vent air to the heat chamber of the fireplace. The presence of the vent air conduits in the heat exchange volume of the fireplace obstructs the flow of ambient room air through the heat exchange volume and thereby detracts from the exchange of heat from the firebox panels to the flow of air cycled through the heat exchange volume by the fireplace blower.
Gas fireplaces have also been developed with an angled flue pipe that not only could be directed upwardly from the heat chamber of the fireplace as in conventional fireplaces, but could also be directed horizontally from the heat chamber to exhaust combustion fumes from the heat chamber out through a side wall of the building containing the fireplace. However, the angled flue pipe connected to the fireplace outer shell required extra available room outside the fireplace outer shell to accommodate the angled flue pipe. This, at times, would require that the fireplace be moved out from the wall of the room containing the fireplace thereby decreasing the rooms floor space, or required a larger enclosure of the fireplace flue outside the building containing the fireplace to accommodate the angled flue pipe, thus increasing the costs involved in installing the fireplace.
In addition, connecting an angled flue pipe to a fireplace to communicate the flue pipe with the heat chamber of the fireplace firebox would often require the addition of an angled firebox panel extending upwardly from the top edge of the back panel to the rear edge of the top panel of the firebox. The exhaust opening communicating with the angled flue pipe would be provided in the angled panel. However, the angled panel would extend downwardly from the top panel of the firebox and would usually be visible through the access opening of the firebox. Thus, the exhaust opening of the firebox would be viewable from the room containing the fireplace, detracting from the aesthetic appearance of the fireplace. A system of horizontal and vertical baffle plates were employed in the firebox heat chamber to conceal the exhaust opening. The baffles were connected between the side panels and the back panel of the firebox and between the side panel and the top panel of the firebox, concealing the exhaust opening while providing a flow path for combustion fumes from the heat chamber to the exhaust opening. However, the system of baffles had the detrimental effect of shielding portions of the firebox panel interior surfaces from the heat of combustion and thereby detracted from the ability of the fireplace to heat ambient room air circulated around the firebox.
What is needed to overcome the disadvantages associated with prior art direct vent gas fireplaces is a direct vent gas fireplace constructed with the beneficial features of an angled directional flue pipe that does not require additional space outside the fireplace outer shell to accommodate and support the angled flue pipe, an exhaust opening baffle that covers the exhaust opening from view but does not shield the firebox panels from the combustion heat in the heat chamber, and a system for directing vent air to the heat chamber without significantly obstructing the flow of ambient room air through the heat exchange volume of the fireplace.
SUMMARY OF THE INVENTION
The basic construction of the direct vent gas fireplace of the invention is similar to that of prior art gas fireplaces in that it includes a firebox supported in and surrounded by an outer shell and an angled flue pipe that enables the outlet end of the flue pipe to be directed either vertically or horizontally. However, the gas fireplace of the invention includes novel structural features that improve its efficiency in transferring heat of combustion to ambient room air cycled through the fireplace and also provide the fireplace with a self-contained, supporting structure for the angled flue pipe that contains a majority of the flue pipe within the outer shell and therefore can be installed in a home or building without having to accommodate and support an angled flue pipe projecting from the fireplace.
The fireplace is basically constructed from formed sheet metal panels that are connected toget
Beasey Corbit
Christensen David M.
Flick Christopher L.
Zahm Robert B.
American Hearth Systems, Inc.
Bennett Henry
Cocks Josiah C.
Thompson & Coburn LLP
LandOfFree
Direct vent fireplace with baffled, directional exhaust and... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Direct vent fireplace with baffled, directional exhaust and..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Direct vent fireplace with baffled, directional exhaust and... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2949152