Patent Publication Number: US-7216645-B2

Title: Wood burning stove having pivoting baffle and method

Description:
This application is a continuation of application Ser. No. 09/809,627, filed Mar. 15, 2001, now U.S. Pat. No. 6,688,302 , which claims the benefit of U.S. Patent Provisional Application Ser. No. 60/189,561, filed Mar. 15, 2000, which applications are incorporated herein by reference. 

   FIELD OF THE DISCLOSURE 
   This disclosure relates generally to wood burning stoves. In particular, this disclosure relates to wood burning stoves having a baffle for regulation of air flow within the stove, and methods of using the stove. 
   BACKGROUND OF THE DISCLOSURE 
   Whether for providing heat, for purely decorative purposes, or for value enhancement, wood burning stoves have become commonplace in today&#39;s building trades for both residential and commercial applications for situations where a fireplace is not feasible or desired. In some instances, wood burning stoves have been inserted into fireplace boxes. Stoves are often preferred over open fireplaces because many wood stoves have the capability to heat large spaces efficiently. Most stoves are able to burn for extended periods of time, such as over night, without refueling or reloading, further enhancing the preference over fireplaces. 
   With this extended burning of wood as the primary fuel comes the challenge of providing an efficient stove that meets the Environmental Protection Agency requirements and state agency requirements for emissions, including particulate material and gases. Many wood burning stoves utilize a catalytic combustor to finalize the burning process and reduce particulate materials and gases. However, the catalytic combustors can become fouled or otherwise rendered inefficient, especially when other than selected materials are burned within the stove. Additionally, the catalytic combustors are quite expensive and must be periodically replaced. 
   In order to avoid using a catalytic combustor, many stove designs are aimed at providing optimum airflow within the burning chamber so that complete combustion, reduction of particulates and unburned gases, and optimum heat generation are obtained. The airflow patterns are generally created by the addition of various channels and/or baffles within the stove, in particular, within the main combustion chamber, to create a secondary combustion chamber. The use of fixed or stationary baffle plates for manipulating air flow within the combustion chamber are known for wood burning stoves, and are discussed, for example, in U.S. Pat. No. 4,766,876 (Henry et al.), U.S. Pat. No. 5,113,843 (Henry et al.), and U.S. Pat. No. 5,341,794 (Henry et al.), each of which is incorporated in its entirety herein by reference. 
   Depending on the design of the various channels or baffles, loading of wood into the stove can be hampered. For example, some baffles are positioned extending essentially parallel to the top surface of the stove. If the stove is a top-loading stove, that is, where wood can be inserted into the combustion chamber through the top surface of the stove, such baffles hinder access to the combustion chamber. What is desired is an improved stove design having optimal air flow patterns to increase combustion efficiency, reduce emissions, and provide easy access to the combustion chamber. 
   SUMMARY OF THE DISCLOSURE 
   The present disclosure provides a stove, in particular, a wood burning stove, that has a baffle assembly disposed within to provide optimal air flow patterns within the stove. A portion of the baffle assembly is pivotable to provide easy access to the combustion chamber to allow loading of fuel into the stove. 
   In particular, the stove includes a stove body which defines a stove exterior, a stove interior, and a combustion chamber disposed within the interior. A baffle plate is disposed within the combustion chamber, the baffle plate being moveable from a “closed” configuration to an “open” configuration. When in the “closed” configuration, the baffle plate is positioned substantially horizontally and is spaced apart from at least a portion of at least one wall. When in the “open” configuration, the baffle plate is positioned substantially vertically such that a by-pass pathway is created between a top access door and the combustion chamber. This allows for easy top-loading of fuel. 
   When in the “closed” configuration, air within the combustion chamber flows from the combustion chamber, around the baffle plate, through a passage between the baffle plate and the stove body, and out a chimney. When in the “open” configuration, a by-pass pathway is formed separate from the passage, so that air within the combustion chamber flows from the combustion chamber, through the by-pass pathway, and out the chimney. The by-pass pathway does not exist if the baffle plate is in the closed configuration. Preferably, the baffle plate is pivotable. 
   An air manifold is preferably present within the combustion chamber, having air flow communication with the exterior of the stove. In one embodiment, the air manifold provides a pivot point for the baffle plate. In one such embodiment, the baffle plate and the air manifold pivot together. 
   It will also be understood that while a wood fueled stove will be described with respect to the preferred embodiments, the disclosure is not limited to wood burning structures, but could equally apply to stove using other fuel sources. Further, while the present disclosure will be described made of sheet metal material, the disclosure is not to be limited to any particular material, but could be used with other known constructions, such as ceramic and other known materials. These and other modifications of the disclosure will be understood by those skilled in the art in view of the following description of the disclosure, with reference to specific preferred embodiments thereof. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Referring to the figures, wherein like numerals represent like parts throughout the several views: 
       FIG. 1  is a front view of a stove of the present invention; 
       FIG. 2  is a side view of a first embodiment of the stove incorporating the principles of this disclosure, illustrating the external stove structure and internal baffle assembly in a “closed” configuration; 
       FIG. 3  is a side view of the stove of  FIG. 2 , illustrating the external stove structure and internal baffle assembly in an “open” configuration; 
       FIG. 4  is an exploded schematic view of the baffle assembly shown in  FIGS. 2 and 3 ; 
       FIG. 5  is a front view of a portion of the baffle assembly shown in  FIG. 4 ; 
       FIG. 6  is a bottom view of the portion of the baffle assembly shown in  FIG. 5 ; 
       FIG. 7  is a side view of the portion of the baffle assembly shown in  FIGS. 5 and 6 ; 
       FIG. 8  is a partial side view of the stove of  FIG. 2 , illustrating the direction of air flow around the baffle assembly in a “closed” configuration; 
       FIG. 9  is a partial side view of the stove of  FIG. 3 , illustrating the direction of air flow by-passing the baffle assembly in an “open” configuration; 
       FIG. 10  is a top view of the stove of  FIG. 2 , with the baffle assembly in the “closed” configuration; 
       FIG. 11  is a top view of the stove of  FIG. 3 , with the top access door open and the baffle assembly in the “open” configuration; 
       FIG. 12  is a cut-away side view of a second embodiment of the stove incorporating the principles of this disclosure, illustrating the external stove structure and internal baffle assembly in a “closed” configuration; 
       FIG. 13  is a side view of the stove of  FIG. 12 , illustrating the external stove structure and the internal baffle assembly in an “open” configuration; 
       FIG. 14  is a front view of a portion of the baffle assembly shown in  FIG. 12 ; 
       FIG. 15  is a side view of the portion of the baffle assembly shown in  FIG. 14 ; 
       FIG. 16  is a bottom view of the portion of the baffle assembly shown in  FIG. 14 ; 
       FIG. 17  is a perspective view of the portion of the baffle assembly shown in  FIG. 14 ; and 
       FIG. 18  is an exploded schematic view of the baffle assembly shown in  FIGS. 14 and 17 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
   Wood is generally burned in the stove, although other types of solid fuels can also be burned in the stove. The following description and figures are in reference to a wood burning stove, although it is to be understood that the function of the stove elements is not dependent on the type of fuel burned. 
   A stove  10  is shown in  FIG. 1 . Stove  10  has an enclosed body  12  defined by first side wall  14 , opposite second side wall  16 , a top wall  17 , a front wall  18 , a bottom wall  19 , and a back wall, not shown. Together, these various walls define an combustion chamber within the walls. Although body  12  is described with six walls (four periphery side walls, a top wall and a bottom wall), body  12  can be any shape. In general, the body  12  is defined by a top wall, a bottom wall, and at least one side wall. Body  12  is situated on a pedestal or foot  15 , which elevates body  12  above the surface on which it is supported. Typically, stove  10  is metal, such as cast iron. 
   A first door  20  is disposed within front wall  18 , however, a door such as first door  20  can be provided in any of side walls  14 ,  16 , front wall  18  or the back wall of stove  10 . Door  20  is pivotally openable by hinges  22  attached to front wall  18 . A handle  25  facilitates opening and closing of door  20 . Door  20  can include a window  24  to allow viewing of the combustion chamber within the stove  10 . A second door  30  is disposed within top wall  17  and is pivotally openable by hinges (not shown) attached to top wall  17 . Door  30  may include a handle or other mechanism to facilitate opening and closing of door  30 . Each of doors  20 ,  30  can be used to place fuel, such as wood logs, into the combustion chamber of stove  10 . 
   A stack, flue or chimney  40  is provided to allow the exhaust gases generated by the burning fuel to exit the stove  10 . Included in stove  10  are various air intake apertures and channels, to provide air to the interior of the combustion chamber. Handles  42 ,  44  can be used to manipulate the flow of intake air. 
   The above description of stove  10  has been fairly general. It is understood that any variation in the structure of stove  10  can be used with the moveable baffle assembly of the present disclosure. 
   Stove  10 , in accordance with the present disclosure, includes a handle  75  extending from body  12 . Handle  75 , which is part of a handle assembly, extends into the combustion chamber and is moveable as desired to manipulate the baffle assembly contained within the combustion chamber. The baffle assembly and its various elements will be now explained in detail, with reference to a first embodiment shown in  FIGS. 2 and 3 , and a second embodiment shown in  FIGS. 12 and 13 . 
   Referring now to  FIGS. 2 ,  3 ,  12 , and  13 , stove  10  is shown in side view with the baffle assembly of the present disclosure viewable through the stove body. The baffle assembly of the present disclosure generally includes a baffle plate  50 ,  150 , an air manifold  60 ,  160 , and mounting members  80 ,  180  fixed to the combustion chamber side of the side walls. A handle assembly  70 ,  170  is provided to facilitate moving baffle plate  50 ,  150 . A fixed baffle plate  56 ,  156  is also included in the baffle assembly shown. 
     FIGS. 4 through 7  show various elements of a first embodiment of the baffle assembly. In  FIG. 4 , the various elements are shown in exploded view; in  FIGS. 5 through 7 , a portion of the baffle assembly is shown. In particular, in accordance with the present disclosure and shown in each of  FIGS. 4 through 7 , a moveable baffle plate  50  is provided. Baffle plate  50  has a generally planar, solid face  52 . Various strengthening features, such as ribs and the like, may be included in or on baffle plate  50 . A fixed baffle plate  56 , shown in  FIG. 4 , is also provided in the baffle assembly. Fixed baffle plate  56  is fixed to the combustion chamber side of the back wall of the stove  10 . Baffle plates  50 ,  56  are typically made from a sheet of metal, such as steel or cast iron, although other materials, such as ceramic materials, can be used. 
   Disposed proximate to baffle plate  50  is an air manifold  60  for providing and further manipulating air flow within the combustion chamber. The air manifold creates a secondary combustion area beneath the baffle plate and above the primary combustion area. Both the primary and secondary combustion areas are located in the combustion chamber. Air manifold  60  includes a first manifold section  62  and a second manifold section  64 . In particular, first manifold section  62  is shown as an axial structure about which the manifold  60  can be pivoted, and second manifold section  64  is a D-shaped structure extending out from first section  62 . Manifold sections  62 ,  64  are tubular structures that allow air flow there through. Air enters manifold  60  via intake  65  and exits manifold sections  62 ,  64  through apertures  68  disposed within manifold sections  62 ,  64 . Preferably, a portion of air manifold  60 , specifically a portion having intake  65 , is in air flow communication with the exterior of the stove body  12 . In one embodiment, intake  65  is connected to channels within the mounting members  80  that are connected to the exterior of the stove  10 . These channels may meet the exterior at the stove sides, stove back, or at other locations. 
   Baffle plate  50  is connected to second manifold section  64  at connection point  54  and to first manifold section  62  at connection point  55 . Together, baffle plate  50 , air manifold  60 , and fixed baffle plate  56  manipulate the air and smoke flow within the combustion chamber of stove  10  so that optimum temperature and combustion are realized therein. 
   Mounting members  80  are positioned adjacent to, and typically attached to, the combustion chamber side of the side walls. Mounting members  80  provide a seat or support against which the baffle plate  50  can rest when baffle plate  50  is in the “closed” position. Mounting members  80  may manipulate the air flow patterns somewhat. At least a portion of the mounting members  80  typically extends into the combustion chamber some distance from the wall on which it is attached. 
   Although mounting members  80  are shown as two oppositely placed pieces (see  FIG. 4 ), mounting member  80  can be a single structure positioned on only one side wall  14  of  16 , or on the front wall  18 , or on the back wall. Alternately, mounting member  80  can be a single structure that is positioned on two or more walls. Further, in some embodiments it may be desirable to incorporate fixed baffle plate  56  with mounting member  80 , thus having one structure that provides the desired air flow pattern and supports the moveable baffle plate  50 . 
   The baffle assembly further includes a handle assembly  70  constructed to connect to, and move, baffle plate  50  and manifold  60  from the “open” to the “closed” configuration. Handle assembly  70  has a first position and a second position; when in the first position, the baffle plate  50  is in its “open” configuration, and when in the second position, the baffle plate  50  is in its “closed” configuration. 
   Handle assembly  70  includes a first section  72 , second section  74 , and third section  76 , which are connected together and to baffle plate  50 . A handle  75  is connected to first section  72  and is disposed on the exterior of stove  10  so that a consumer can grab and move handle  75  as desired. Although shown with three sections  72 ,  74 ,  76 , it is understood that any handle assembly  70  configuration can be used to move baffle plate  50 . 
   When the baffle assembly is disposed within the stove, baffle plate  50  is moveable, preferably pivotable, from an “closed” configuration to an “open” configuration. Baffle plate  50  and air manifold  60  are mounted within stove  10  in any manner to allow the desired movement from the “closed” configuration to the “open” configuration. In one embodiment, air manifold  60  is pivotally attached to mounting members  80 , for example, in close proximity to intake  65 . In such an attachment design, first manifold section  62  is an axis for rotation, or pivoting, of manifold  60 . Because baffle plate  50  is attached to manifold  60  at points  54 ,  55 , baffle plate  50  will move in congruence with manifold  60 . In another embodiment, the pivoting of baffle plate  50  and manifold  60  are fixedly attached to handle assembly  70 ; this point of attachment is the pivot point. See for example,  FIG. 7 , in which reference numeral P designates a potential pivot point. 
     FIGS. 14 through 18  show various elements of a second embodiment of the baffle assembly, in which the air manifold is expanded. In  FIG. 18 , the various elements are shown in exploded view; in  FIGS. 14 through 17 , a portion of the baffle assembly is shown. In particular, in accordance with the present disclosure and shown in each of  FIGS. 14 through 18 , a moveable baffle plate  150  is provided. Baffle plate  150  has a generally planar, solid face  152 . Various strengthening features, such as ribs and the like, may be included in or on baffle plate  150 . A fixed baffle plate  156 , shown in  FIG. 18 , is also provided in the baffle assembly. As shown in  FIG. 18 , fixed baffle plate  156  is fixed to the combustion chamber side of the back and/or side walls of the stove  10  via rear mounting member  204 . It is to be understood that fixed baffle plate  156  can alternatively be fixed to the rear portion of the mounting members  180 . Baffle plates  150 ,  156  are typically made from a sheet of metal, such as steel or cast iron, although other materials, such as ceramic materials, can be used for baffle plates  150 ,  156 . 
   Disposed proximate to baffle plate  150  is an air manifold  160  for providing and further manipulating air flow within the combustion chamber. The air manifold creates a secondary combustion area beneath the baffle plate and above the primary combustion area within the combustion chamber. Air manifold  160  includes a first manifold section  162 , a second manifold section  164 , a third manifold section  200 , and a fourth manifold section  201 . In the illustrated embodiment, first, second, and third manifold sections  162 ,  164 ,  200  are shown as tubular structures connected to end pieces  205  about which the first, second, and third manifold sections  162 ,  164 ,  200  can be pivoted. A fourth, fixed, manifold section  201  is a tubular structure extending between, and fixed to, mounting members  180 . Manifold sections  162 ,  164 ,  200 ,  201  are tubular structures that allow air flow there through. Air enters manifold  160  via intake  165  and exits manifold sections  162 ,  164 ,  200  through apertures  168  disposed within manifold sections  162 ,  164 ,  200 . Air enters fourth manifold section  201  via intake  210  and exits through apertures  168  disposed within fourth manifold section  201 . Preferably, a portion of air manifold  160 , specifically a portion having intake  165 , is in air flow communication with the exterior of the stove body  12 . Additional intake  210  is in air flow communication with the fourth tubular section  201  and with the exterior of the stove body  12 . In one embodiment, intakes  165 ,  210  are connected to channels  250 ,  260 , respectively, within mounting members  180  that are connected to the exterior of the stove  10 . These channels may be joined together under mounting members  180  and exit through the wall of the stove as a single channel, or they may exit separately. These channels may meet the exterior at the stove sides, stove back, or at other locations. 
   Baffle plate  150  is connected to end pieces  205 . Together, baffle plate  150 , air manifold  160 , and fixed baffle plate  156  manipulate the air and gas flow within the combustion chamber of stove  10  to create a secondary combustion area above the primary combustion area so that optimum temperature and combustion are realized in the stove. In one embodiment, insulation panels  202 ,  203  are included in the baffle assembly. Insulation panels  202 ,  203  are constructed of insulating material to reflect heat back into the combustion chamber from the baffle assembly and thereby maximize the temperature within the combustion chamber during all burn conditions, and thereby encouraging secondary and tertiary combustion above the fuel bed. In a further embodiment, the insulation panels  202 ,  203  may also provide structural support for the baffle plates  150 ,  156 . The insulation panels  202 ,  203  may be made of any suitable insulating material. In one embodiment, the insulation panels  202 ,  203  are ceramic. 
   Mounting members  180  are positioned adjacent to, and typically attached to, the combustion chamber side of the side walls. Mounting members  180  provide a seat or support against which the baffle plate  150  can rest when baffle plate  150  is in the “closed” position. Mounting members  180  may manipulate the air flow patterns somewhat. At least a portion of mounting members  180  typically extends into the combustion chamber some distance from the wall on which it is attached. 
   Although mounting members  180  are shown as two oppositely placed pieces (see  FIG. 18 ), mounting members  80  can be a single structure positioned on only one side wall  14  of  16 , or on the front wall  18 , or on the back wall. Alternately, mounting members  180  can be a single structure that is positioned on two or more walls. Further, in some embodiments it may be desirable to incorporate fixed baffle plate  156  with mounting members  180 , thus having one structure that provides the desired air flow pattern and supports the moveable baffle plate  150 . 
   The baffle assembly further includes a handle assembly  170  constructed to connect to, and move, baffle plate  150  and manifold  160  from the “open” to the “closed” configuration. Handle assembly  170  has a first position and a second position; when in the first position, the baffle plate  150  is in its “open” configuration, and when in the second position, the baffle plate  150  is in its “closed” configuration. 
   Handle assembly  170  includes a first section  172 , second section  174 , and third section  176 , which are connected together and to baffle plate  150 . A handle  175  is connected to first section  172  and is disposed on the exterior of stove  10  so that a consumer can grab and move handle  175  as desired. Although shown with three sections  172 ,  174 ,  176 , it is understood that any handle assembly  170  configuration can be used to move baffle plate  150 . 
   When the baffle assembly is disposed within the stove, baffle plate  150  is moveable, preferably pivotable, from an “closed” configuration to an “open” configuration. Baffle plate  150  and air manifold  160  are mounted within stove  10  in any manner to allow the desired movement from the “closed” configuration to the “open” configuration. In one embodiment, air manifold  160  is pivotally attached to mounting members  180  through end pieces  205 , for example, in close proximity to intake  165 . In such an attachment design, the end pieces  205  provide an axis for rotation, or pivoting, of manifold  160 . Because baffle plate  150  is attached to manifold  160 , baffle plate  150  will move in congruence with manifold  160 . In another embodiment, the pivoting of baffle plate  150  and manifold  160  are fixedly attached to handle assembly  170 ; this point of attachment is the pivot point. See for example,  FIG. 15 , in which reference numeral P designates a potential pivot point. 
   Referring to  FIGS. 8 and 9 , partial side views of stove  10  are shown with the baffle plate  50  in the “closed” and “open” configurations, respectively. The pivot point for these embodiments is intake  65 . In both  FIGS. 8 and 9 , the air flow pattern, mostly the flow pattern of smoke and combustion gases, is depicted by the arrows  300 ,  301 . 
   In  FIG. 8 , the baffle plate  50  is in the “closed” configuration with baffle plate  50  seated against mounting members  80 . In this configuration, the baffle plate  50  is spaced apart from at least a portion of the front wall  18  forming a passage  400  from the combustion chamber to the chimney  40 . The passage  400  may be formed in any location where the baffle plate is spaced apart from at least a portion of a side wall. Handle  75  is in a first position. Baffle plate  50 , and air manifold  60 , are substantially horizontal. Smoke and gases rise from the burning wood, (not shown, but which is typically on the base wall of the stove), and is directed by baffle plate  50  toward front wall  18 . The smoke and gases flow generally parallel to baffle plate  50 . The smoke and gases then pass through the passage  400 , around and over baffle plate  50  and mounting members  80 , and flow out chimney  40 , as indicated by arrow  300 . 
   In  FIG. 9 , handle  75  is in a second position and the baffle plate  50  is in the “open” configuration with baffle plate  50  not seated against mounting members  80 ; baffle plate  50  is displaced from its seat on mounting members  80  and a by-pass pathway  100 , separate from passage  400 , is opened. In the position shown, baffle plate  50  and air manifold  60  are substantially vertical, and the by-pass pathway  100  is formed between the “open” baffle plate  50  and the fixed baffle  56 . With baffle plate  50  pivoted to the “open” position, smoke and gases are able to move through by-pass pathway  100 , as indicated by arrow  301 . The smoke and gases flow generally parallel to baffle plate  50  through by-pass pathway  100 . In  FIG. 9 , stove  10  is also shown with door  30  opened to provide access from the exterior to the interior of stove  10 . 
     FIGS. 10 and 11  show schematic top views of stove  10 . In  FIG. 10 , door  30  is closed, and baffle plate  50  and manifold  60  are in the “closed” configuration; in  FIG. 11 , door  30  is open, and baffle plate  50  and manifold  60  are in the “open” configuration. It can be seen that when in the “open” configuration, access into the combustion chamber of stove  10  is generally unobstructed. 
   Fuel, such as wood, can be loaded into stove  10  by various methods. In one embodiment, first door  20  can be pivoted on hinges  22  to open an access port to the combustion chamber. Prior to opening door  20 , handle  75  is optionally moved from its first position to its second position, thereby moving baffle plate  50  from the “closed” configuration to the “open” configuration. Moving baffle plate  50  to the “open” configuration will open a by-pass channel  100  to allow smoke and gases to pass from the combustion chamber, through by-pass channel  100 , out chimney  40 . In this embodiment, baffle plate  50  minimizes the amount of smoke that might exit through door  20  when door  20  is opened. 
   In another embodiment, fuel is loaded through the second door  30 , located in top wall  17 . Handle  75  is moved from its first position to its second position, thereby moving baffle plate  50  from the “closed” configuration to the “open” configuration. Moving baffle plate  50  to the “open” configuration will open by-pass channel  100  to allow smoke and gases to pass from the combustion chamber, through by-pass channel  100 , and out chimney  40 . Further, moving baffle plate  50  to the “open” configuration will provide a generally unobstructed access to the interior so that wood can be lowered into the combustion chamber through door  30  in top wall  17 . In this embodiment, baffle plate  50  not only minimizes the amount of smoke that might exit through door  30  when door  30  is opened, but the pivotable baffle plate  50  provides an area through which wood can be easily passed for top loading. 
   The above specification has been provided to illustrate specific examples of embodiments incorporating the principles of this disclosure. Those skilled in the art will readily recognize other applications and configurations that fall within the scope of this disclosure. Since many embodiments of the disclosure can be made without departing from the spirit and scope of the disclosure, the disclosure resides in the claims hereinafter appended.