Abstract:
A burner assembly for a domestic gas cooktop includes a lower burner mounting structure positioned on a first side of the top sheet; a burner body configured to be positioned on an opposite side of the top sheet, the burner body having an igniter positioning surface; an igniter having an igniter end, and a stop integrally formed in the igniter, the stop having an upper ledge; and an urging member that pushes against the lower burner mounting structure, and urges the igniter in a direction away from the lower burner mounting structure and toward the igniter positioning surface such that the upper ledge of the stop is urged into contact with the igniter positioning surface when the burner assembly is in an assembled condition. The igniter is held in an operating position by the burner body and the urging member when the burner assembly is in use.

Description:
FIELD OF THE INVENTION 
       [0001]    The invention is directed to an apparatus and method related to properly positioning the igniter in a burner of a gas cooktop. 
         [0002]    An example of an application for the invention is a domestic kitchen gas cooktop having an improved burner igniter locating structure. 
       BACKGROUND OF THE INVENTION 
       [0003]    Some modern domestic kitchens include a gas cooktop as either a countertop mounted cooktop or as a part of a standalone range. 
         [0004]    In some domestic appliances, such as a gas cooktop, an igniter is used to create a spark between the igniter and another part of the cooktop to light the gas supplied to the burner. For example, an igniter can create a spark in a gap between the igniter and a metallic burner head that is positioned on the top of the burner body. The consistency and reliability of the creation of the gap and, as a result, the spark is instrumental in reliable and consistent lighting and relighting of the burner. 
         [0005]    With some igniter configurations, it can be difficult to accurately locate the igniter such that the size of the gap is within design parameters. This difficulty can result from how the igniter is held in place and to what part of the cooktop the igniter is attached. Certain attachment methods, especially those that attach the igniter to the burner body, can also present difficulties during assembly in that it is necessary to hold the top sheet of the cooktop above, and in close proximity to, the lower portion of the cooktop so that wires can be connected to the igniter. This can be especially difficult if the cooktop has multiple, such as five or six, burners. This operation can often require two assembly workers to complete. 
         [0006]    Some igniters are held in position by a friction fit into a bracket that is fastened to a burner body. This attachment method can be problematic because the friction fit can wear over time, possibly resulting in an improper spark gap and associated inconsistent lighting of the burner. 
         [0007]    Applicants recognized these problems and developed a solution as described herein. 
       SUMMARY 
       [0008]    The invention achieves the benefit of more precise and repeatable igniter placement and simpler assembly. The invention achieves this benefit by providing an igniter that is attached to the lower burner mounting structure below the top sheet. The igniter is attached to the lower burner mounting structure using a spring or other urging member that pushes the igniter toward the burner body. The igniter is captured such that it will stay attached to the lower burner mounting structure even without the top sheet in place. The igniter includes a stop that provides a ledge for the urging member on its lower side and a ledge that is pressed down by an underside of the burner body when the burner body and top sheet are lowered into an operating position. Because the igniter is located in the operating position by a surface-to-surface engagement with the burner body itself by being pressed into position by the urging member (and not a friction fit that can move over time), the igniter head is more precisely and repeatably positioned. In addition, because the igniter is captured by the lower burner mounting structure and held in place before the top sheet (and associated burner body) is lowered into position, the igniter wiring can be attached to the igniter without having to hold the top sheet. 
         [0009]    Particular embodiments of the invention are directed to a burner assembly for a domestic gas cooktop having a top sheet. The burner assembly includes a lower burner mounting structure configured to be positioned on a first side of the top sheet; a burner body configured to be positioned on a second side of the top sheet, the second side of the top sheet being opposite the first side of the top sheet, the burner body having an igniter positioning surface; an igniter having an igniter end, and a stop integrally formed in the igniter, the stop having an upper ledge; and an urging member that pushes against the lower burner mounting structure, and urges the igniter in a direction away from the lower burner mounting structure and toward the igniter positioning surface of the burner body such that the upper ledge of the stop is urged into contact with the igniter positioning surface of the burner body when the burner assembly is in an assembled condition. The igniter is held in an operating position by the burner body and the urging member when the burner assembly is in use. 
         [0010]    Other embodiments of the invention are directed to a domestic gas cooktop. The domestic cooktop includes a top sheet; a gas manifold below the top sheet; and a burner assembly having a lower burner mounting structure positioned on a first side of the top sheet, a burner body positioned on a second side of the top sheet, the second side of the top sheet being opposite the first side of the top sheet, the burner body having an igniter positioning surface, an igniter having an igniter end and a stop integrally formed in the igniter, the stop having an upper ledge, and an urging member that pushes against the lower burner mounting structure and urges the igniter in a direction away from the lower burner mounting structure and toward the igniter positioning surface of the burner body such that the upper ledge of the stop is urged into contact with the igniter positioning surface of the burner body when the burner assembly is in an assembled condition. The igniter is held in an operating position by the burner body and the urging member when the domestic gas cooktop in use. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    The following figures form part of the present specification and are included to further demonstrate certain aspects of the disclosed features and functions, and should not be used to limit or define the disclosed features and functions. Consequently, a more complete understanding of the exemplary embodiments and further features and advantages thereof may be acquired by referring to the following description taken in conjunction with the accompanying drawings, wherein: 
           [0012]      FIG. 1  is a partial sectional view of a cooktop having a friction fit igniter attached to a burner body; 
           [0013]      FIG. 2  is a perspective view of a friction fit igniter for attaching to a burner body; 
           [0014]      FIG. 3  is a partial sectional view of the cooktop having a friction fit igniter attached to a burner body; 
           [0015]      FIG. 4  is a partial sectional view of a cooktop in accordance with embodiments of the invention; 
           [0016]      FIG. 5  is a partial sectional view of a cooktop in accordance with embodiments of the invention; 
           [0017]      FIG. 6  is a partial plan view of a cooktop in accordance with embodiments of the invention; 
           [0018]      FIG. 7  is a partial sectional view of a cooktop in accordance with embodiments of the invention where the cooktop is in an assembled state; and 
           [0019]      FIG. 8  is a partial sectional view of a cooktop in accordance with embodiments of the invention where the cooktop is in a partially assembled state. 
       
    
    
     DETAILED DESCRIPTION 
       [0020]    The invention is described herein with reference to the accompanying drawings in which exemplary embodiments of the invention are shown. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. 
         [0021]    In the description of embodiments disclosed herein, any reference to direction or orientation is merely intended for convenience of description and is not intended in any way to limit the scope of the present invention. Relative terms such as “lower,” “upper,” “horizontal,” “vertical,”, “above,” “below,” “up,” “down,” “top” and “bottom” as well as derivative thereof (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should be construed to refer to the orientation as then described or as shown in the drawing under discussion. These relative terms are for convenience of description only and do not require that the apparatus be constructed or operated in a particular orientation. Terms such as “attached,” “connected,” “coupled,” “interconnected,” and similar refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise. 
         [0022]    As explained above, embodiments of the invention provide a solution to the problems associated with an igniter attached to a burner body. 
         [0023]      FIGS. 1-3  show an example of a burner assembly  100  that is part of a gas cooktop. Some cooktops have a plurality of burner assemblies  100 . In this example, burner assembly  100  has a metal burner body  110  that has a plurality of flame apertures  120 . Although a metal burner body is shown, other temperature resistant materials can be used. A metal burner head  115  (shown in  FIG. 3 ) sits on top of burner body  110 . Although a metal burner head is shown, other temperature resistant materials can be used. Gas supplied through a gas supply line  140  travels through a gas valve that controls the flow of gas to burner assembly  100 . The gas then travels through a venturi and out of a gas outlet  130 . The gas then escapes through flame apertures  120 , where it is lit by a sparking or other lighting device. In this example, an igniter  150  creates a spark across gap A between an igniter head  160  and burner head  115 . It is noted that gap A shown in  FIG. 3  is not necessarily to scale and the proper gap distance depends on factors such as, for example, igniter power, igniter material, and burner head material. 
         [0024]    In this example, gas supply line  140  and the gas valve are positionally fixed relative to a lower burner mounting structure  195 . Burner body  110  is mounted to a top sheet  190  of the cooktop. Top sheet  190  can be a piece of sheet material, such as, for example, sheet metal, that forms the main surface that is seen by the user when the cooktop is in use. 
         [0025]    As shown in  FIG. 2 , igniter  150  has an igniter head  160  at one end and an igniter electrical connection  170  at the opposite end. Igniter  150  is press fit into a hole in an igniter mounting bracket  180 . As shown in  FIGS. 1 and 3 , igniter mounting bracket  180  is attached to burner body  110 . The location of igniter head  160  relative to burner head  110 , and therefore burner head  115 , is initially fixed once igniter mounting bracket  180  is attached to burner body  110 . In this example, igniter mounting bracket  180  is held to burner body  110  by a bolt or other fastener. Spark gap A is determined by the position of igniter head  160  relative to burner head  115 , as shown in  FIG. 3 . The press fit connection between igniter  150  and igniter mounting bracket  180  can lead either initially, or over time, to an incorrect spark gap that can result in inconsistent lighting of the burner. In addition, the connection of igniter mounting bracket  180  to burner body  110  and the possible distortion of igniter mounting bracket  180  can lead to an incorrect spark gap. 
         [0026]    The designs shown in  FIGS. 1-3  also present difficulties during assembly in that it is necessary to hold the top sheet of the cooktop above, and in close proximity to, the lower structure of the cooktop so that wires can be connected to the igniter. This can be especially difficult if the cooktop has multiple, such as five or six, burners. This operation can often require two assembly workers to complete 
         [0027]    Applicants recognized these shortcomings of the designs shown in  FIGS. 1-3  and developed embodiments of the invention to avoid these problems. 
         [0028]      FIG. 4  shows an exemplary embodiment having an igniter that is attached to the lower burner mounting structure and is urged into place by a spring. 
         [0029]      FIG. 4  shows a burner assembly  400  that is part of a gas cooktop. Some cooktops have a plurality of burner assemblies  400 . In this example, burner assembly  400  has a metal burner body  410  that has a plurality of flame apertures  420 . Although a metal burner body is shown, other temperature resistant materials can be used. A metal burner head  415  sits on top of burner body  410 . Although a metal burner head is shown, other temperature resistant materials can be used. Gas supplied through a gas supply line  440  travels through a gas valve that controls the flow of gas to burner assembly  400 . The gas then travels through a venturi and out of a gas outlet  430 . The gas then escapes through flame apertures  420 , where it is lit by a sparking or other lighting device. In this example, an igniter  500  creates a spark across a gap between a top  540  of igniter  500  and burner head  415 . It is noted that the gap shown in  FIG. 4  is not necessarily to scale and the proper gap distance depends on factors such as, for example, igniter power, igniter material, and burner head material. 
         [0030]    In this example, gas supply line  440  and the gas valve are positionally fixed relative to a lower burner mounting structure  495 . Burner body  410  is mounted to a top sheet  490  of the cooktop. Top sheet  490  can be a piece of sheet material, such as, for example, sheet metal, that forms the main surface that is seen by the user when the cooktop is in use. 
         [0031]    Igniter  500  is shown in this example as a one-piece igniter having a stop  510  formed in its main body  520 .  FIG. 5  shows igniter  500  when burner assembly  400  is in an assembled condition. In this condition, top  540  of igniter  500  extends through a hole in burner body  410 , and an upper ledge  512  of stop  510  is pushed up against a lower surface of burner body  410 . Igniter  500  is pushed upward by a spring  610  acting on a lower ledge  514  of stop  510  and an upper surface of lower burner mounting structure  495 . Spring  610  pushes igniter  500  upward into a repeatable position relative to burner body  410 . Although a coil spring is shown in this example, other urging members can be used to push igniter toward burner body  410 . The positional relationship of burner head  415  relative to burner body  410  is fixed (even though burner head  415  is removable from burner body  410 ) because burner head  415  and burner body  410  are made from dimensionally stable materials and have defined connection points. Due to this stability in the relative position of burner body  410  and burner head  415 , a spark gap G between top  540  of igniter  500  and burner head  415  is precise and repeatable. In this example, top  540  of igniter  500  is directly vertically below burner head  415 . 
         [0032]    Also shown in  FIG. 5  is top sheet  490  and a hole  492  in top sheet  490  through which igniter  500  passes during assembly of top sheet  490  to the cooktop lower structure. Hole  492  is large enough for stop  510  and spring  610  to pass through hole  492  during assembly of top sheet  490  to the cooktop lower structure. Igniter  500  also has an electrical connection  470  to which wires are attached to provide power and/or control to igniter  500 . A groove  530  exists in main body  520  to receive a clip  600 . Clip  600  prevents spring  610  from pushing igniter  500  out of lower burner mounting structure  495  when top sheet  490  is not in the operating position. Although a clip and a groove are shown in this example, other retaining structures can be used to prevent movement of igniter  500  relative to lower burner mounting structure  495 . 
         [0033]      FIGS. 6 and 7  show another exemplary configuration of embodiments. In this configuration, top  540  of igniter  500  is not directly vertically below burner head  415 . As shown in  FIG. 6 , head  540  of igniter  500  is located horizontally between two legs of five star legs of burner head  415 . While a star shaped burner head is shown in this example, other shaped burner heads can be used. 
         [0034]      FIG. 7  is similar to  FIG. 5 , except that spark gap G between burner head  415  and top  540  of igniter  500  is angled relative to vertical. This is the condition that would exist in a configuration such as that shown in  FIG. 6 . 
         [0035]    Both  FIG. 5  and  FIG. 7  show examples of the position of igniter  500  when the cooktop is in an operating condition with top sheet  490  and burner body  410  in place in the operating condition. In these Figures, spring  610  is in a more compressed state than when top sheet  490  and burner body  410  are not in place in the operating condition (described below). 
         [0036]      FIG. 8  shows the position of igniter  500  when top sheet  490  and burner body  410  are not in the operating position. In this condition, spring  610  pushes igniter  500  upward until clip  600  contacts a lower surface of lower burner mounting structure  495  and stops any further upward movement of igniter  500 . This feature is extremely helpful during assembly of the cooktop because igniter  500  can be assembled to lower burner mounting structure  495  and held in place by clip  600  while the necessary wires are connected to electrical connection  470 . All of the igniters in the cooktop (often five or six) can be assembled in this manner before top sheet  490 , with attached burner bodies  410 , is put in place on the cooktop lower structure. As top sheet  490  with burner bodies  410  is lowered into position on the cooktop lower structure, the head  540  of each igniter  500  will protrude though the appropriate hole in the associated burner body  410  until the lower surface of each burner body  410  comes into contact with the top ledge  512  of stop  510  of its associated igniter  500 . At this point, igniters  500  will be in the precise operating position, as shown in  FIGS. 5 and 7 . Spring  610  is sufficiently strong to press igniter  500  upward to firmly contact the lower surface of the burner body  410  while, at the same time, is not too strong to prevent top sheet  490  from moving sufficiently downward to rest in the operating position. 
         [0037]    As can be seen in the above exemplary embodiments, the invention provides a solution to problems associated with igniters that are attached to a burner body prior to the top sheet being installed onto the cooktop lower structure, and problems associated with igniters that are press fit into mounting brackets. 
         [0038]    It will be appreciated that variants of the above-disclosed and other features and functions, or alternatives thereof, may be combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the invention. In addition, all combinations of any and all of the features described in the disclosure, in any combination, are part of the invention.