Abstract:
A sealed gas burner for a cooking range has a venturi tube assembly which is attached directly to a range top of the cooking range. A burner cup slidingly and releasably engages a venturi tube of the venturi tube assembly which extends through the range top. A burner cap releasably engages the burner cup and it defines a plurality of burner ports. The burner cup and the burner cap define an annular gas chamber in communication with the burner ports. The burner ports can be cleaned by removing only the burner cap. Additional cleaning of the burner and the range top can be accomplished by removing both the burner cap and the burner cup.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to sealed gas burners for cooking ranges. More particularly, the present invention relates to a simplified sealed gas burner which is more economical to produce and which can be easily removed from the cooking range in order to facilitate the cleaning of both the gas burner and the cooking range.  
         BACKGROUND AND SUMMARY OF THE INVENTION  
         [0002]    Conventional domestic household cooking ranges are generally comprised of a planar range top and a plurality of sealed burners. These gas burners can be divided into two styles, the first being an open cook top burner and the second being a sealed cook top burner. Open cook top burners are normally supported by structure which is located below the range top and the burner extends through a burner opening in the range top. There is an annular space or clearance that exists between the burner head and the burner opening. This annular space or opening can vary in width from one-half of an inch to one and one-half inches and over the years this has presented problems to the range designers, the range manufacturers and the end users of the range. This annular space or clearance can allow food spills to fall through to the underlying burner box and this annular space or clearance can also provide a non-intended opening for flue products to vent, especially when an oven or any other burner compartment located below the top section begins to operate. Sealed gas burners have been developed to overcome some of these problems.  
           [0003]    Sealed gas burners are secured in place within one or more apertures with the outer periphery of the sealed gas burner mating with the range top to eliminate any type of annular space or clearance between the burner and the range top. The elimination of this annular space or clearance stops food spillage from dropping into the burner box below the range top and it eliminates any problems associated with the venting of flue products. The sealed gas burner provides a clean streamlined appearance which facilitates both the cleaning and the maintenance of the range top.  
           [0004]    A typical prior art sealed gas burner assembly includes a die cast metal burner body which is covered by a removable die cast metal top to form a gas chamber. The burner body includes a sidewall having a plurality of burner ports formed therein and through which the primary air/gas mixture is passed to the exterior of the burner body for combustion. Other typical prior art sealed gas burner designs include a stamped burner top which is crimped to a stamped burner base to form the sealed gas chamber.  
           [0005]    A major disadvantage to these prior art designs for sealed gas burners has been the difficulty of the procedure required when cleaning the cooking range, the burner assembly and the overall costs involved with their manufacture. The burner assemblies having a removable top allowed access to the gas chamber and the burner ports formed in the burner body, but removal of the burner body for cleaning of the cooking range normally required some type of tool to release a special fastener securing the burner body to the cooking range. The stamped burner designs have been manufactured such that they are removable from the range top but the designs for the crimped assemblies have severely limited access to the internal gas chamber and the inside portion of the burner ports for cleaning.  
           [0006]    Still other prior art stamped metal burner assemblies have been developed to overcome the problems associated with the assembly and cleaning of the burners and the cooking range. These newer designs of sealed gas burners include a stamped steel base which is attached to the cooking top using a twist lock connection between the burner base and the cooking range. The twist lock feature eliminates the need for special tools for removing the burner base from the cooking range. A stamped metal burner cap engages the burner base using a fluid tight slip fit such that the burner cap can be easily removed from the burner base with its associated burner ports for cleaning. The sealed gas burner is designed to telescopically engage an air/fuel mixer tube which extends between the gas valve and the burner opening in the range top.  
           [0007]    While the prior art sealed gas burners have performed satisfactorily for cooking ranges, the continued development of sealed gas burners has been directed to sealed gas burners which are more economical to produce while still providing all the advantages of simplicity of assembly and convenience in cleaning.  
           [0008]    The present invention provides the art with a unique three piece stamped sealed gas burner which comprises a venturi tube, a burner cup and a burner cap. The venturi tube includes a bracket for attachment of the tube to the range top. The burner cup slidingly engages the venturi tube, which is designed to extend through the range top. The burner cup forms the bottom portion of a pocket which holds the gas and air mixture for supply to the burner ports. The burner cap is positioned over the burner cup. The burner cap includes a pair of locating posts which engage a pair of respective indentations in the burner cup to locate the burner cap with respect to the burner cup. One of the two posts serves as the grounding point for the igniter. The burner ports are formed into the lower surface of the burner cap. The sealed gas burner of the present invention provides an economical sealed gas burner which requires less assembly time and has fewer chances of having quality problems. The sealed gas burner is easier to keep clean because the burner ports are located in the burner cap and the burner cap can be easily removed for cleaning.  
           [0009]    Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:  
         [0011]    [0011]FIG. 1 is a side view of the unique sealed gas burner in accordance with the present invention;  
         [0012]    [0012]FIG. 2 is a cross-sectional side of the venturi tube assembly illustrated in FIG. 1;  
         [0013]    [0013]FIG. 3 is a top plan view of the venturi tube assembly illustrated in FIGS. 1 and 2;  
         [0014]    [0014]FIG. 4 is a cross-sectional side view of the burner cup illustrated in FIG. 1;  
         [0015]    [0015]FIG. 5 is a top plan view of the burner cup illustrated in FIGS. 1 and 4;  
         [0016]    [0016]FIG. 6 is a cross-sectional side view of the burner cap illustrated in FIG. 1; and  
         [0017]    [0017]FIG. 7 is a bottom plan view of the burner cap illustrated in FIGS. 1 and 6.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0018]    The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.  
         [0019]    Referring now to the drawings in which like reference numerals designate like or corresponding parts throughout the several views, there is shown in FIG. 1, a sealed gas burner in accordance with the present invention and which is designated generally by the reference numeral  10 . Sealed gas burner  10  comprises a venturi tube assembly  12 , a burner cup  14  and a burner cap  16 . Sealed gas burner  10  is attached to a cooking range top  18  using one or more screws  20 . Gas is supplied to sealed gas burner  10  through a supply tube  22  which connects sealed gas burner  10  with a supply of flammable gas (not shown) through a gas valve (not shown) as is well-known in the industry. Preferably, supply tube  22  includes a two hundred fifty thousands inch diameter tube.  
         [0020]    Referring now to FIGS.  1 - 3 , venturi tube assembly  12  comprises a venturi tube  30 , a gas fitting  32 , a gas orifice  34 , a bracket  36  and an igniter  38 . Venturi tube  30  is fabricated from aluminized steel tubing. Venturi tube  30  defines two windows  40  cut into the opposite sides of venturi tube  30  to allow air to mix with the gas supplied from gas orifice  34 . At the upper end of windows  40 , venturi tube  30  forms a seat  42  against which bracket  36  is Icoated. Venturi tube  30  also defines a beaded section  44  which sandwiches bracket  36  between seat  42  and beaded section  44  to secure bracket  36  to venturi tube  30 . Gas fitting  32  is disposed within the lower end of venturi tube  30  and the bottom end of venturi tube  30  is formed at  46  to fit within a groove  48  defined by gas fitting  32  for securing gas fitting  32  to venturi tube  30 . Gas fitting  32  defines a hexagonally shaped section  50  which supports gas fitting  32  when supply tube  22  is attached to gas fitting  32  using a threaded section  52  located on the end of gas fitting  32 . Gas orifice  34  is threadingly received by gas fitting  32  and it controls the amount of gas being supplied to venturi tube  30  and thus to sealed gas burner  10 .  
         [0021]    Bracket  36  defines a flange  54  which is sandwiched between seat  42  and beaded section  44  of venturi tube  30 . Bracket  36  defines a plurality of threaded bores  56  (two on opposite sides of bracket  36  in the embodiment illustrated) each of which threadingly receive a respective screw  20  for securing bracket  36  and thus venturi tube assembly  12  to range top  18 . Bracket  36  also includes an extending arm  58  which defines an aperture  60  within which igniter  38  is located. Igniter  38  is secured to arm  58  using a retainer  62  as is well-known in the art. Igniter  38  is attached to an electrical circuit which provides a spark for igniting the air/gas mixture as is well-known in the art. When venturi tube assembly  12  is attached to range top  18 , the upper end of venturi tube  30  extends through an aperture  64  defined by range top  18  and igniter  38  extends through an aperture  66  also defined by range top  18 . Beaded section  44  is designed to locate venturi tube assembly  12  within aperture  64  as is illustrated in FIGS. 1 and 2.  
         [0022]    Referring now to FIGS. 1, 4 and  5 , burner cup  14  is fabricated from aluminum which is preferably forty-thousandths in thickness. The drawing operation which forms burner cup  14  draws the originally supplied material such that burner cup  14  is preferably six hundred thousandths in depth. The bottom of burner cup  14  defines an upwardly formed section  70  which helps to move the gas and air mixture to the ports as detailed below. Formed section  70  also acts to form a pocket or reservoir for the gas and air mixture to ensure an uninterrupted supply of this mixture to the ports when sealed gas burner  10  is operating on low, as well as to provide a reservoir of this mixture to dampen any pressure fluctuations. The center of formed section  70  defines a flange  72  which in turn defines an aperture  74 . Aperture  74  slidingly engages venturi tube  30  of venturi tube assembly  12  with flange  72  providing a sufficient surface area of contact to avoid any significant leaking of the gas and air mixture between burner cup  14  and venturi tube  30 .  
         [0023]    The outer surface of burner cup  14  defines a pair of indentations  76  which are used to locate burner cap  16  as detailed below. One of the pair of indentations  76  is utilized as a positioning cove for igniter  38 . Indentations  76  in conjunction with burner cup  14  form a location for a soft flame within the indentation that will relight sealed gas burner  10  if it goes out due to operating the burner in the low setting and opening or closing an oven door.  
         [0024]    The upper end of burner cup  14  forms a flange  78  which is preferably one hundred twenty-five thousandths wide. Flange  78  supports burner cap  16  and with indentations  76  which are carried through flange  78 , locates burner cap  16 . In addition, flange  78  serves as the base for the burning ports formed in burner cap  16  as detailed below.  
         [0025]    Referring now to FIGS. 1, 6 and  7 , burner cap  16  is formed from steel into a hat shaped disc. Preferably, burner cap  16  is one hundred forty-thousandths in thickness. Burner cap  16  defines a formed center section  80  which creates a flange  82  around the outer edge of burner cap  16 . Preferably, flange  82  is one-half inch in width. A plurality (thirty to thirty-six in the preferred embodiment) of radially extending ports  84  are formed into flange  82  and a pair of locating posts  86  are formed to extend from flange  82 . The base of ports  84  is provided by flange  78  on burner cup  16 . Locating posts  86  engage indentations  76  on burner cup  14  to locate burner cap  16  with respect to burner cup  14 . In addition, one of locating posts  86  serves as a grounding point for igniter  38  as shown in FIG. 1. The shape of locating posts  86  are designed to help direct the gas and air mixture to igniter  38 .  
         [0026]    Each of the plurality of ports  84  is a triangular shaped port having an included angle  88  preferably of forty-five degrees. The angular shape of ports  84  allows for increased spacing between adjacent ports  84 . The increased spacing allows for more secondary air entrainment which is required to complete combustion. Even though the angular shape allows for increased spacing, this increase in spacing still positions adjacent ports  84  close enough to promote flame chaining. One advantage to the forty-five degree triangular shaped of ports  84  is that they allow for easier manufacturing of burner cap  16 .  
         [0027]    In addition to the plurality of radially extending ports  84 , an auxiliary port  88  is formed adjacent to each locating post  86 . Each auxiliary port  88  provides the gas and air mixture into a respective indentation  76  of burner cup  14 . This supply of gas and air mixture results in the ignition of the flame by igniter  38  as well as maintaining a soft flame within indentations  76 . This soft flame will relight sealed gas burner  10  if the burner goes out due to operation of the burner in the low setting and opening and closing the oven door.  
         [0028]    The center of formed center section  80  is contoured downward in order to disperse the gas and air mixture directly to ports  84  and  88 . The shape of the contour of formed center section  80  is designed in such a way that the gas and air mixture is directed to an annular pocket  90  (FIG. 1) formed by formed section  70  of burner cup  14  and formed center section  80  of burner cap  16 . Annular pocket  90  forms a reservoir which helps to prevent sealed gas burner  10  from going out when the oven door is opened or closed by reducing the pressure fluctuations in sealed gas burner  10 . This provides a more consistent flame which is less likely to be affected by the various external factors.  
         [0029]    Sealed gas burner  10  described above, is more economical to provide and has less chance of experiencing quality problems, especially quality problems which occur due to human error. The simple design for sealed gas burner  10  will result in a significant reduction in assembly time. Once placed in service, sealed gas burner  10  is easier to keep clean because ports  84  are in burner cap  16  which is easily removable for cleaning purposes. When additional cleaning is necessary, burner cup  14  is also easily removed providing complete access to range top  18 .  
         [0030]    The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.