Abstract:
A fireplace insert comprising: a gas burner, a fuel/air control valve coupled to the gas burner, a blower coupled to the gas burner, and a controller coupled to the fuel/air control valve and the blower; wherein the controller controls at least one operational parameter of the fuel/air control valve and the blower to produce a flame pattern generated by the gas burner. A method of manufacturing is also provided.

Description:
TECHNICAL FIELD 
       [0001]    This application is directed, in general, to a fireplace and, more specifically, to a modulating flame gas fireplace. 
       BACKGROUND 
       [0002]    Even with the advent of central heat, many homes and business still use fireplaces. In some instances, they are used to produce additional heat for a given space, however, in other applications, their presence is purely aesthetic. Many of the advances in fireplace technology have primarily been in the arena of providing fireplace systems that are designed to better transfer the heat generated by the fire. This has particularly been the case with the advent of natural gas fireplaces that are much cleaner and more convenient than conventional wood-burning fireplaces. 
       SUMMARY 
       [0003]    One aspect provides a fireplace insert comprising: a gas burner, a fuel/air control valve coupled to the gas burner, a blower coupled to the gas burner, and a controller coupled to the fuel/air control valve and the blower; wherein the controller controls at least one operational parameter of the fuel/air control valve and the blower to produce a flame pattern generated by the gas burner. 
         [0004]    A method of manufacturing a fireplace insert comprising: providing a gas burner, coupling a fuel/air control valve to said gas burner, coupling a blower to said gas burner, and coupling a controller to said fuel/air control valve and said blower wherein said controller controls at least one operational parameter of said fuel/air control valve and said blower to produce a flame pattern generated by said gas burner. 
     
    
     
       BRIEF DESCRIPTION 
         [0005]    Reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which: 
           [0006]      FIG. 1  is a partial sectional view of one embodiment of a fireplace insert constructed in accordance with the principles of the present disclosure; 
           [0007]      FIG. 2  is a sectional view of the burner and flame pattern of  FIG. 1 ; 
           [0008]      FIG. 3  is a partial sectional view of an alternative embodiment of the fireplace insert; 
           [0009]      FIG. 4  is a partial sectional view of a second alternative embodiment of the fireplace insert; and 
           [0010]      FIG. 5  is a partial sectional view of a third alternative embodiment of the fireplace insert. 
       
    
    
     DETAILED DESCRIPTION 
       [0011]      FIG. 1  illustrates a partial sectional view of one embodiment of a fireplace insert  100  constructed in accordance with the principles of the present disclosure. In this embodiment, the fireplace insert  100  comprises: a gas burner  110 , a fuel/air control valve  120 , a blower  130 , and a controller  140 . The gas burner  110  may be of any desired shape; however, gas burners having a particular horizontal geometric cross section  2 A- 2 A, e.g., circular, rectangular, elliptical, inverted cone, etc., have special application in that they readily produce flame cross sections  2 A′- 2 A′ that reflect, or are similar, to that of the burner horizontal geometric cross section, i.e., circular, rectangular, elliptical, inverted cone, etc., respectively. A gas burner  110  with a circular cross section is illustrated in  FIG. 2 . Also, in one configuration, the gas burner  110  may have a bowl-shaped vertical cross section as can be seen in  FIG. 1  and the flame pattern  150  has a similar vertical cross section emanating from the top  111  of the gas burner  110 . Some of the geometric cross sections into which the gas burner may be configured are illustrated and discussed below. One who is of ordinary skill in the art will readily conceive of other geometric cross sections applicable within the principles of the present disclosure. 
         [0012]    In certain embodiments, the fuel/air control valve  120 , the blower  130 , and the controller  140  of the fireplace insert  100  may be powered by conventional line voltage of 110-115 VAC. However, in other embodiment, the fuel/air control valve  120 , the blower  130 , and the controller  140  may be powered by direct current. The blower  130  is pneumatically coupled to the gas burner  110  through a duct  160 , such as gas pipes, which has the fuel/air control valve  120  interposed the blower  130  and the gas burner  110 . The controller  140  comprises a microprocessor with a programmable memory for controlling at least one operational parameter of the fuel/air control valve  120  and the blower  130 . In one embodiment, the controller  140  may command a set program over a specified period of time and then cyclically repeat the program. In another embodiment, the controller  140  may be set to command a varying function so as to give the appearance of a traditional wood fireplace with varying flame colors and heights. In an alternative embodiment, the controller  140  may be replaceable as a complete unit or a plug-in board, each different unit having a specific program preprogrammed. Alternatively, the controller  140  may be reprogrammed through a USB connection to a personal computer. 
         [0013]    The operational parameters of the fuel/air control valve  120  and the blower  130 , in certain embodiments, may include the following: fuel (natural gas or propane) velocity, air velocity, fuel/air ratio, and an equivalence ratio. The fuel velocity may be controlled by setting the fuel/air control valve  120  with the controller  140  sensing the line gas pressure and adjusting the fuel/air control valve  120  appropriately. The air velocity may be controlled by the rotation speed of the blower  130  and the setting of the fuel/air control valve  120  by the controller  140 . The fuel/air ratio may be controlled by the controller  140  when it sets the fuel/air control valve  120  for the proper mix to obtain a desired fuel/air ratio. The equivalence ratio φ is defined as: (F/A ratio) actual  divided by (F/A ratio) stoichiometric . One who is of skill in the art is familiar with the meaning of a stoichiometric fuel/air ratio. The equivalence ratio may be determined by the controller  140  for appropriate adjustment as necessary for a desired flame pattern or color. 
         [0014]    The operational parameters of the fuel/air control valve  120  and the blower  130  can affect the flame pattern. For example, if a constant fuel/air ratio is maintained, but the volume of fuel and air is increased, the length of the flame will increase. That is, height h of the flame pattern is a direct function of the volume of fuel and air delivered to the burner  110  by the blower  130 . If the constant fuel/air ratio is maintained, but the volume of fuel and air is decreased, the length of the flame will also decrease. If the flow volume of fuel and air is increased by increasing fuel while holding the air constant, then the flame will tend to be more yellow in color. If the opposite is commanded, i.e., the flow volume of fuel and air is increased by increasing air while holding the fuel volume constant, then the flame will tend to be more toward blue in color. These various operational parameters of the fuel/air control valve  120  and the blower  130  are controlled by the controller  140  adjusting the fuel/air mixture with the fuel/air control valve  120  and the flow volume by increasing or decreasing the rotational speed of the blower  130 . By adjusting one or more of the operational parameters, a very artistic flame having different heights, colors, or both over a programmed period of time may be easily achieved. The time may be varied in such a way so to create a constant changing flame or produce repeated patterns over a set period of time, much in the same way as a water fountain might be operated. 
         [0015]      FIG. 2  illustrates a sectional view of the burner  110  and flame pattern of  FIG. 1 . As can be seen, the flame pattern reflects the burner shape. 
         [0016]      FIG. 3  illustrates another embodiment of a fireplace insert  300 . In this particular embodiment, the fireplace insert  300  comprises: a multiple gas burner  310 , a fuel/air control valve  320 , a blower  330 , and a controller  340 . The number of gas burners  310  may vary depending on the desired design. FIG.  3  illustrates one such design that is configured as a dual gas burner. The illustrated dual gas burner  310  has two concentric bowl-shaped burners  311 ,  312 . The fuel/air control valve  320 , blower  330 , and controller  340  combine to produce two concentric flame patterns  351 ,  352  from the two concentric bowl-shaped burners  311 ,  312 . In this configuration, the flame patterns of the individual burners  311 ,  312  will be substantially parallel to each other because the individual burners  311 ,  312  are fed and controlled by the same fuel/air control valve  320 , blower  330 , and controller  340 . However, one flame pattern h 1 , h 2  may be longer or shorter than the other by controlling the fuel/air entrance orifices  313 ,  314  of each burner  311 ,  312 , respectively. 
         [0017]    As with previous embodiments, the operational parameters of the fuel/air control valve  320  and the blower  330  can be varied to affect the flame pattern and be operated and controlled by way of the controller  340  in the manner described above, such that by adjusting one or more of the operational parameters, a very artistic flame having different heights, colors, or both over a programmed period of time may be easily achieved. The time may be varied in such a way so to create a constant changing flame or produce repeated patterns over a set period of time, much in the same way as a water fountain might be operated. 
         [0018]      FIG. 4  illustrates a partial sectional view of a second alternative embodiment of a fireplace insert  400 . The fireplace insert  400  comprises: first, second, and third gas burners  411 ,  412 ,  413 , a fuel/air control valve  420 , a blower  430 , and a controller  440 . All three gas burners  411 ,  412 ,  413  are fed from the same fuel/air control valve  420 , blower  430 , and controller  440 . In this configuration, the first and second gas burners  411 ,  412  are inverted cone-shaped. The first and second gas burners  411 ,  412  produce inverted, truncated cone-shaped flame patterns  415 ,  416 , respectively, that may be varied in color by adjusting the flow velocity for each burner  411 ,  412 . For the first and second burners  411 ,  412 , this is achieved by selection of the size of the aperture  419  in a split disk  414  surrounding a central tube  417  that feeds the third burner  413 . The third gas burner  413  may be designed to produce a conventional single flame that is more yellow in color. This color is achieved by controlling the aperture size of a flared end  418  of the central tube  415 . Flame heights of the burners  411 ,  412 ,  413  and the overall flame patter may be controlled as detailed above with respect to other embodiments. 
         [0019]      FIG. 5  illustrates a partial sectional view of a third alternative embodiment of the fireplace insert  500 . In this particular embodiment, the fireplace insert  500  comprises: first through fifth gas burners  511 - 515 , first and second fuel/air control valves  521 ,  522 , first and second blowers  531 ,  532 , and first and second controllers  541 ,  542 . Though the design may vary, the illustrated embodiment shows the first and second gas burners  511 ,  512  configured as two concentric bowl-shaped burners  511 ,  512 . The third, fourth, and fifth gas burners  513 ,  514 ,  515  may be conventional single flame burners. The first and second gas burners  511 ,  512  are served by the first fuel/air control valve  521 , the first blower  531 , and first controller  541 . The third, fourth and fifth gas burners  513 ,  514 ,  515  are served by the second fuel/air control valve  522 , the second blower  532 , and the second controller  542 . Each of the first and second controllers  541 ,  542  may have different programs to enhance contrast between the two types of burners, i.e., the first and second gas burners  511 ,  512  vs. the third, fourth and fifth gas burners  513 ,  514 ,  515 . Flame height and color of each set of burners are controlled as detailed above. 
         [0020]    Thus, a fireplace insert has been described that controls not only the height of the flame pattern emanating from multiple burners, but also, the shape and color of the flames. 
         [0021]    For the purposes of this discussion, use of the terms “providing” and “forming” includes: manufacture, subcontracting, purchase, etc. Those skilled in the art to which this application relates will appreciate that other and further additions, deletions, substitutions and modifications may be made to the described embodiments.