This invention relates generally to methods for operating wood fired appliances, and more specifically, to methods for operating wood fired appliances having a cooperating top loading door and movable baffle.
Prior to EPA particulate emissions regulations for wood heaters, established the late 1980's, numerous models of conventional wood stoves enjoyed the sales benefit of the convenience feature of being capable of fueling by way of a top loading door.
Consequently, in order to comply with EPA regulations, many manufacturers opted for utilizing a non-catalytic secondary combustion design. This typically employed what is commonly known as a “Scandinavian” baffle in combination with a secondary air source directly below the baffle to achieve low particulate emissions performance, or “clean burn.” These non-catalytic woodstoves employ a fixed position horizontal or near horizontal Scandinavian baffle and a series of tubes or a manifold to supply diffused secondary air directly beneath the baffle to provide for the “clean burn” characteristic. Scandinavian baffle designs, however, do not allow for fuel to be loaded through a top door to the firebox as the baffle effectively blocks vertical delivery to the firebox by impeding a majority of access to the firebox fuel holding area.
Woodstoves incorporating Scandinavian, or horizontal baffles, have an extended flame path which promotes cooler stack temperatures with the benefit of minimized flue gas temperature entering the chimney. The cooler stack temperature allows closer installation clearances to combustibles (adjacent walls and structure) in comparison to other typical top loading non-catalytic technology currently available and of comparable energy output.
In the past several years there have been introductions of non-catalytic designs featuring a top loading door. The majority of currently available, non-catalytic wood heaters with top loading door capability incorporate a secondary combustion or “down drafting” firebox system and a bypass damper at the flue entrance. Down drafting does not employ a baffle but instead the bypass damper or bypass gate directs the products of primary combustion downward through the coal bed into an entrance to a secondary combustion chamber located behind the firebox. The hot gases are exposed to a secondary air source in the secondary combustion chamber to achieve low emissions performance. Consequently, the lack of a secondary baffle in these systems allows for a top loading feature. In order to refuel the non-catalytic wood heaters with top loading door, the bypass gate must be opened allowing a straight path to the chimney, otherwise large amounts of combustion products would enter the room should the fuel load door be opened.
An example, of a wood burning stove having a top loading door and down-draft combustion is the LEYDEN top loading cast iron wood stove available from Lopi Fireplace and manufactured by Travis Industries.
U.S. Pat. Nos. 6,688,302 and 7,216,645 issued to Henry et al. disclose a wood burning stove having a manually operated top loading door and a manually operated movable baffle. The baffle is movable to a position behind the opening when the top loading door is opened for loading the wood burning stove and for directing combustion gas behind the opening in the stove and out the chimney. The lower portion of the baffle is disposed in the combustion chamber when the baffle is in the open position. In addition, the lower portion of the baffle is also maintained in the combustion chamber when moving the baffle to the closed position to the open position.
There is a need for further methods for operating wood fired appliances, and more specifically, to methods for operating wood fired appliances having a cooperating top loading door and movable baffle.
In a first aspect, the present invention provides a method for operating a wood fired appliance to produce heat. The method includes exhausting gas from a combustion chamber past a bottom surface of a baffle disposed in a raised open position, below an open first opening in a top wall, and out a flue, loading wood through the first opening, past the raised baffle, and into the combustion chamber, automatically moving the baffle to a lowered closed position from the raised open position in response to a top loading door being moved to a closed position to close the opening in the top wall, automatically inhibiting the baffle from being maintained in the raised opened position when the top loading door is disposed in the closed position, and exhausting gas from the combustion chamber between a top surface of the baffle disposed in the lowered closed position and a bottom surface of the top loading door disposed in the closed position, and out the flue.
In a second aspect, the present invention provides a method for operating a wood fired appliance to produce heat. The method includes exhausting gas from a combustion chamber past a bottom surface of a baffle disposed in a raised open position, below an open first opening in a top wall, and out a flue, loading wood through the first opening, past the raised baffle, and into the combustion chamber, moving a top loading door to a closed position to close the first opening in the top wall to engage a cam and rotate the baffle about an axis past a center vertical position so that the baffle falls under the force of gravity to a lowered closed position, inhibiting the baffle with the cam from being rotated about the axis past the center vertical position to the raised open position when the top loading door is disposed in the closed position, and exhausting gas from the combustion chamber between a top surface of the baffle disposed in a lowered closed position and a bottom surface of the top loading door disposed in the closed position, and out the flue.
In a third aspect, the present invention provides a method for operating a wood fired appliance to produce heat. The method includes providing the wood fired appliance having a housing, a top loading door movable between an open position to permit access to a first opening and a closed position to cover the first opening, and a movable baffle disposed below the first opening, exhausting gas from a combustion chamber in the housing between a top surface of the baffle and a bottom surface of the top loading door disposed in a closed position, and out the flue, opening the top loading door to access the first opening, moving the baffle to the raised open position from a lowered position to define a second opening in fluid communication with the flue, exhausting gas from the combustion chamber through the second opening, below the open first opening, and out the flue, loading wood into the combustion chamber, closing the top loading door to cover the first opening, tripping the baffle, via the closing of the top loading door, to fall under the force of gravity to a lowered closed position from the raised open position, and inhibiting the baffle from being maintained in the raised open position when the top loading door is disposed in the closed position.
In a fourth aspect, the present invention provides a method for operating a wood fired appliance to produce heat. The method comprising providing the wood fired appliance comprising a housing having a combustion chamber therein and a top wall, a movable top loading door for covering an opening in the top wall of the housing, a rotatable baffle having an end pivotally attached to the housing and rotatable about an axis, the baffle positionable in a lowered generally horizontal closed position below and spaced-apart from the opening in the top wall to define a first passageway for directing exhaust gas from a front of the housing between a top of the baffle and a bottom of the top loading door, and out a flue, and rotatable to a raised past center vertical position to define an opening for loading wood into the combustion chamber and for directing exhaust gas from the combustion chamber through the opening and out the flue, a cam pivotally attached to the housing, the cam comprises a upper leg and a lower leg, the lower leg engagable with an upper end portion of the baffle, and the upper leg being disposed above the top wall when the baffle is disposed in the raised open position and engagable with the lower leg, and wherein the upper leg of the cam is engagable with the top loading door for lowering the rotatable baffle to the lowered closed position from the raised open position when the top loading door is lowered to cover the opening in the top wall of the housing. The top loading door is opened and a baffle is moved to the raised open position from the lowered closed position. Wood is loaded into the combustion chamber and the top loading door is closed. A first arm of a cam engages the top loading door to cause a second arm of the cam to move the baffle from the raised open position to the lowered closed position under the force of gravity to cover the opening to the combustion chamber. Gas is exhausting from the combustion chamber between a top surface of the baffle and a bottom of the top loading door, and out the flue.
In a fifth aspect, the present invention provides a method for operating a wood fired appliance to produce heat. The method includes providing the wood fired appliance having a housing, a top loading door movable between an open position to permit access to a first opening and a closed position to cover the first opening, and a movable baffle disposed below the first opening, and exhausting gas from a combustion chamber in the housing between a top surface of the baffle and a bottom surface of the top loading door disposed in a closed position, and out the flue. The top loading door is opened to access the first opening, and the baffle is moved to the raised open position from a lowered position to define a second opening in fluid communication with the flue. The baffle is disposed substantially away from the combustion chamber in the when in the raised open position and in the lowered closed position. Gas is exhausted from the combustion chamber through the second opening, below the open first opening, and out the flue. Wood is loaded into the combustion chamber, the top loading door is closed to cover the first opening, and then the baffle is closed.
The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the concluding portion of the specification. The invention, however, may best be understood by reference to the following detailed description of various embodiments and the accompanying drawings in which:
The present invention is generally directed to methods for operating a top loading wood fired appliances having a Scandinavian-style baffle configuration. In one aspect, the method for operating a wood fired appliance generally includes a cooperating top loading door and movable baffle. For example, method for operating a wood fired appliance may include automatically moving a baffle to a lowered closed position from the raised open position in response to a top loading door being moved to a closed position to close the opening in a top wall. The baffle may also be automatically inhibited from being maintained in the raised opened position when the top loading door is disposed in the closed position. For example, as described in greater detail below, a cam may be tripped or activated by lowering the top loading door to cause the baffle to rotate about an axis and fall under the force of gravity to the lowered closed position. The cam may also inhibit the baffle from being raised when the top loading door is closed. This technique inhibits, if not prevents, the likelihood of the baffle remaining in a raised open position after the loading wood in the wood fired appliance via the top, and closing a top loading door. One advantage of the present invention in inhibiting the baffle from remaining in a raised open position is that it allows for closer clearance installation compared to movable baffles that may inadvertently remain in an raised open configuration which results in hotter combustion gases being exhausted directly out the flue.
It will also be appreciated that the present invention provides for top load door fueling of a non-catalytic wood fired heater employing a Scandinavian style baffle, and accomplished by way of the baffle rotating about an axis from a horizontal or near horizontal position to a past center vertical position. For example, utilizing the front secondary air tube as an axis, allows the baffle to be substantially rotated out of the way, if not entirely out of the way, from accessing the combustion chamber, to facilitate loading fuel into the combustion or firebox chamber via the top load door. The cam lever or interlock mechanism returns the baffle to the original resting horizontal or near horizontal “clean burn position” when the top load door is closed. The cam lever or interlock mechanism operates on a axial cam lever function between the rotating baffle and the top load door to assure that the baffle returns to the horizontal or near horizontal position when the top load door is closed by way of weighted leverage transferred through the cam lever mechanism to the baffle. The cam or interlock mechanism also inhibits the baffle, by means of center of gravity orientation, from being positioned in the vertical or open position when the top load door is closed. With the baffle returning to the clean burn position and automatically inhibited, if not prevented, from remaining in the raised position when the top loading door is closed, the exhaust and flame path length is maximized resulting in minimized flame extension and reduction of high temperature flue gas exiting the flue outlet and entering the chimney connector.
After loading wood in wood fired appliance 10, an operator may use handle 32 to lower top loading door 30. Upon an operator lowering top loading door 30, a front edge portion 34 of top loading door 30 engages a portion of a raised cam 50 to trip or automatically cause the baffle (not shown in
It will be appreciated that other suitable means for supporting the baffle and allowing it to be rotated may be employed. Handle 40 (
The baffle is positionable in a lowered generally horizontal position below and spaced-apart from the closed top loading door 30 and the opening in top wall 24. With the baffle in the lowered closed position, a first passageway is defined for directing exhaust gas from combustion chamber 15 toward a front of housing 12 and between a top surface 64 of baffle 60 and a bottom surface 36 of top loading door 30 (as represented by arrow A), and then out flue. The paths for introduction of primary air for combustion are illustrated by arrows B, and a path for introduction of secondary air for combustion is illustrated by arrow C, D, and E. Also observed in
With reference again to
With reference to
With reference again to
As best shown in
It will be appreciated by those skilled in the art that the configuration of the above-described wood fired appliances result in a baffle that in its raised open position is tripped by the cam upon closing the top loading door to cause the raised baffle to return by itself or fall under the force of gravity to its lowered or closed position. In other words, upon closing the top loading door, the raised baffle is tipped over or tilted passed a vertical center by the cam to cause the raised baffle to return by itself under the force of gravity to its lowered or closed position. This configuration of the wood fired appliance reduces, if not eliminates, the likelihood of the baffle remaining in a raised position after the loading wood in the wood fired appliance via the top, and closing a top loading door.
From the present description, it will be appreciated that the technique of the present invention to trip the movable baffle and inhibit the baffle from remaining in the raised open position when the top loading door is lowered to its closed position, may be accomplished in a number of suitable ways. For example, a fixed or movable cam may be attached to the top loading door which upon lowering the top loading door engages the top portion of the baffle to more, deflect, or tip it past a vertical center position, allowing the baffle to fall under the influence of gravity to the baffle's lowered closed position. In another example, a fixed or movable cam may be attached to the baffle. In a further example, instead of the cam rotating about a pivot, the cam may be suitably configured to cause a linear motion for moving or tripping the baffle. While a single-piece cam has been described and illustrated, it will be appreciated that a plurality of member or pieces may be suitably employed for allowing the top loading door and the baffle to cooperate together in accordance with the present invention. While the cam and the baffle are described and illustrated as pivotable about a single axis, it will be appreciated that the cam and/or the baffle may be suitably pivotable about more than one axis. In a further example, instead of the cam rotating about a pivot, the cam may be suitably configured to cause movement in a linear manner for moving or tripping the baffle. In addition, a spring or biasing member may be suitably employed to cause the top loading door and baffle to cooperate in accordance with the aspects of the present invention. In still another example, the door and the baffle may be suitably liked together, e.g., operable with a single handle, to cooperate in accordance with the aspects of the present invention.
Thus, while various embodiments of the present invention have been illustrated and described, it will be appreciated to those skilled in the art that many changes and modifications may be made thereunto without departing from the spirit and scope of the invention.
Number | Name | Date | Kind |
---|---|---|---|
85614 | Sanford | Jan 1869 | A |
141821 | Sexton | Aug 1873 | A |
163678 | Merrill | May 1875 | A |
232457 | Clement | Sep 1880 | A |
617805 | Burns | Jan 1899 | A |
835915 | Pruitt | Nov 1906 | A |
946701 | Mooney | Jan 1910 | A |
1455290 | Hieb | May 1923 | A |
1688430 | Owens | Oct 1928 | A |
1804988 | Howe | May 1931 | A |
2174347 | Card | Sep 1939 | A |
2196467 | Masonick | Apr 1940 | A |
2348933 | Seeley | May 1944 | A |
2352057 | Wingert | Jun 1944 | A |
2378114 | Van Donk | Jun 1945 | A |
2438123 | Lambert et al. | Mar 1948 | A |
2443910 | Higley | Jun 1948 | A |
2444402 | Klein | Jun 1948 | A |
2461068 | Lockwood | Feb 1949 | A |
2564713 | Miles | Aug 1951 | A |
2781039 | Kaiser et al. | Feb 1957 | A |
3322417 | Mitchell | May 1967 | A |
4154212 | Wilkinson | May 1979 | A |
4192285 | Nietupski | Mar 1980 | A |
4252104 | Morris | Feb 1981 | A |
4263889 | Martenson | Apr 1981 | A |
4280476 | Webb | Jul 1981 | A |
4319556 | Schwartz et al. | Mar 1982 | A |
4337753 | McGinn | Jul 1982 | A |
4338913 | Good | Jul 1982 | A |
4362146 | Schuller | Dec 1982 | A |
4373507 | Schwartz et al. | Feb 1983 | A |
4424799 | Patterson | Jan 1984 | A |
4430986 | Thalis | Feb 1984 | A |
4432335 | Kilham | Feb 1984 | A |
4458662 | Barnett | Jul 1984 | A |
4466419 | Syme | Aug 1984 | A |
4467778 | Babbage et al. | Aug 1984 | A |
4499889 | Syme | Feb 1985 | A |
4510917 | Runquist | Apr 1985 | A |
4580546 | Barnett | Apr 1986 | A |
4582045 | Dorau et al. | Apr 1986 | A |
4651709 | Schnetker | Mar 1987 | A |
4665889 | Rumens et al. | May 1987 | A |
4694820 | Buckner | Sep 1987 | A |
4708123 | Strnad | Nov 1987 | A |
4766876 | Henry et al. | Aug 1988 | A |
4856491 | Ferguson et al. | Aug 1989 | A |
5050579 | Melton et al. | Sep 1991 | A |
5113843 | Henry et al. | May 1992 | A |
5186385 | Karabin et al. | Feb 1993 | A |
5341794 | Henry et al. | Aug 1994 | A |
5435377 | Kratochvil | Jul 1995 | A |
6035812 | Harrigill et al. | Mar 2000 | A |
6688302 | Henry et al. | Feb 2004 | B2 |
7004751 | Malloy et al. | Feb 2006 | B2 |
7216645 | Henry et al. | May 2007 | B2 |
20050279344 | Cyris | Dec 2005 | A1 |
Number | Date | Country |
---|---|---|
1241883 | Sep 1988 | CA |
Entry |
---|
Leyden Top Loading Cast Iron Wood Stove, Travis Industries Inc., printout available online on Mar. 4, 2010, at http://www.lopistoves.com/TravisDocs/98800235.pdf, 4-pages, 2006. |
Shelton, Jay, Solid Fuels Encyclopedia, A Garden Way Book, cover page and p. 99, 1982. |
Hearth & Home, Buyer's Guide 2000-2001, 2 pages, Jul. 2000. |
Number | Date | Country | |
---|---|---|---|
20110168153 A1 | Jul 2011 | US |