Abstract:
A gas cook-top with glass (capacitive) touch controls and automatic burner re-ignition is provided. The gas cook-top utilizes a variable flow gas control valve that is driven by an electronic controller whose user interface provides a glass capacitive touch interface. Various electronic features including safety lockouts and burner re-ignition are provided, as is relational control of the burner flame. As a user moves their finger along a flame adjust indicator, the electronic control positions the variable flow gas valve to control the flame height of the burner to correspond to the relative position along the indicator selected by the user.

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS  
       [0001]     This patent application claims the benefit of U.S. Provisional Patent Application No. 60/741,993, filed Dec. 2, 2005, the teachings and disclosure of which are hereby incorporated in their entireties by reference thereto. 
     
    
     FIELD OF THE INVENTION  
       [0002]     This invention generally relates to gas cook tops, and more particularly to burner flame flow control systems for gas cook tops.  
       BACKGROUND OF THE INVENTION  
       [0003]     Gas cook-tops are valued by homeowners for their superior ability to quickly and precisely control the level of heat. Unfortunately gas levels for cook-tops are typically controlled mechanically by the use of manual rotary valves. This mechanical solution limits the features available to consumers.  
         [0004]     Capacitive Touch (Glass) interfaces are becoming very popular with consumers. Such a user interface is only available with electronic controls. By incorporating electronic controls, these interfaces can provide desirable safety features, such as a child safe burner lockout, which consumers have come to expect.  
         [0005]     Unfortunately, such safety features are expensive and difficult to accomplish with mechanical controls, which current gas cook tops require to control the flame. Such puts the gas cook top at a competitive disadvantage compared with electric cook tops that can use the capacitive touch interfaces.  
         [0006]     There exists, therefore, a need in the art for a gas cook top that incorporates the capacitive touch interface.  
         [0007]     Embodiments of the present invention provide such a gas cook top. These and other advantages of the invention, as well as additional inventive features, will be apparent from the description of the invention provided herein.  
       BRIEF SUMMARY OF THE INVENTION  
       [0008]     In view of the above embodiments of the present invention provide a new and improved gas cook-top. More particularly, embodiments of the present invention provide a new and improved gas cook-top that utilizes a capacitive touch control user interface. Even more particularly, embodiments of the present invention provide a new and improved gas cook-top that utilizes electronic capacitive touch controls that provide enhanced electronically controlled features heretofore unavailable for gas cook-tops.  
         [0009]     In one embodiment of the present invention, a new variable flow gas valve is incorporated into a gas cook-top to allow the use of electronic controls, such as a glass touch interface, to control the level of the burner flame. The control system also provides additional safety features, such as automatic burner re-ignition if the flame blows out, burner lockout if the burner fails to ignite and a child safety burner lockout feature. These additional safety features improve the safety of the gas cook top and reduces the chances of an accident. Glass-touch controls and flat cook-tops are easier to clean than traditional cook-tops and have superior aesthetic appeal than traditional mechanical interface gas cook-tops.  
         [0010]     Other aspects, objectives and advantages of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]     The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the present invention and, together with the description, serve to explain the principles of the invention. In the drawings:  
         [0012]      FIG. 1  is a simplified block diagram of an embodiment of the gas cook-top constructed in accordance with the teachings of the present invention;  
         [0013]      FIG. 2  is a perspective illustration of the gas cook-top of  FIG. 1  illustrated in one aspect of its operation; and  
         [0014]      FIG. 3  is a perspective illustration of the gas cook-top of  FIG. 1  illustrating a further aspect of operation. 
     
    
       [0015]     While the invention will be described in connection with certain preferred embodiments, there is no intent to limit it to those embodiments. On the contrary, the intent is to cover all alternatives, modifications and equivalents as included within the spirit and scope of the invention as defined by the appended claims.  
       DETAILED DESCRIPTION OF THE INVENTION  
       [0016]     In one embodiment of the present invention illustrated in  FIG. 1 , gas cook-top system  10  incorporates variable flow gas valves  22   A-D  that enable the utilization of a Capacitive Touch (Glass) interface  12 . While one embodiment utilizes glass, other materials may also be used as will be recognized by those skilled in the art. A burner ignition system including a flame sense electrode  24   A-D  is utilized to allow the controller  26  to electronically verify the presence of flame at the burners  14   A-D . This combination of controls allows the system to have various capabilities.  
         [0017]     One such capability is touch control. A consumer can ignite the burner and change heat settings, i.e. flame height, with the touch of a finger  16  as illustrated in  FIG. 2  and as will be described more fully below. The system of the present invention also provides in one embodiment an auto re-light feature. The controller  26  will automatically re-ignite the burner  14  if the flame is unintentionally extinguished (e.g. by wind) as sensed by the flame sense electrode  24 . Additionally, an embodiment provides a safety burner lockout feature. If the burner  14  does not ignite within a predetermined period, the controller will automatically terminate the gas flow to that burner  14 . The controller  26  in one embodiment will allow a manual re-attempt to ignite the burner  14 , and in an alternate embodiment will require a purge period to elapse to prevent a build up of gas due to several manual attempts to restart the burner  14 . An embodiment of the present invention also provides a child cook-top lockout feature. That is, the cook-top system  10  can be disabled to prevent a child from accidentally activating a burner  14  by having the user select, e.g. touch the child safety lockout icon  28  on the capacitive touch glass interface  12 . The system  10  of the present invention, in another embodiment, provides an emergency off icon  30  that when touched by the user, will cause the controller  26  to immediately extinguish all burners  14   A-D .  
         [0018]     While those skilled in the art will recognize that the particular operating modes and layout of the capacitive touch glass interface  12  of the embodiment of the present invention illustrated in  FIG. 1  are not limiting to the scope of the present invention, the following will describe this embodiment to aid in the understanding of this system. The illustrated embodiment includes a burner select icon  18   A-D  that is used to enable operation of a particular burner  14   A ,  14   B ,  14   C  or  14   D  on the gas cook-top system  10 . The user first selects the desired burner  14   A ,  14   B ,  14   C  or  14   D  by touching the corresponding icon  18   A ,  18   B ,  18   C  or  18   D . Once the controller  26 , via capacitive touch interface  12 , has detected this operation, the electronic controller  26  will begin to flash the appropriate flame adjust indicator  20   A-D  to provide a visual indication to the user that flame at a particular burner  14   A ,  14   B ,  14   C  or  14   D  will soon be forthcoming.  
         [0019]     In one embodiment, the user would then select a desired flame height from the flame adjust indicator  20  by touching an appropriate location therealong as illustrated in  FIG. 2 . Once the controller  26  has detected the user selection along the flame adjust indicator  20  via the capacitive touch glass interface  12 , electronic controller  26  positions the appropriate gas valve  22   A ,  22   B ,  22   C  or  22   D  (see  FIG. 1 ) to the appropriate position and initiates the gas ignition sequence. Flame then becomes present at the selected burner  14   A ,  14   B ,  14   C  or  14   D  at the corresponding flame height.  
         [0020]     In an alternate embodiment, upon selection of the burner select icon  18 , the controller  26  will flash the appropriate flame adjust indicator  20   A-D  to provide a visual indication to the user that flame at a particular burner  14   A ,  14   B ,  14   C  or  14   D  will soon be forthcoming, and then will adjust the gas valve  22  to the previous setting for that burner  14 , i.e. the last setting prior to that burner  14  being turned off.  
         [0021]     To adjust the flame height, the user simply touches a different location along the flame adjust indicator  20  or simply slides their finger  16  along the length of the flame adjust indicator  20  to vary the flame height as desired (see  FIG. 2 ). As the user selects a different flame height, the capacitive touch interface  12  will detect the particular desired flame height and, via the electronic controller  26 , will adjust the variable flow gas valve  22  to provide a corresponding amount of flow of gas from the gas supply  32  to smoothly adjust the flame height to the desired amount. As the user slides his or her finger  16  along the length of the flame adjust indicator  20 , the electronic controller  26  will correspondingly adjust the variable flow gas valve  22  to adjust the flame height in relation to the movement of the user&#39;s finger  16  as detected by the capacitive touch interface  12 .  
         [0022]     In one embodiment of the present invention, the controller  26  will continuously adjust the flame height at the burner  14  when the user continuously touches the burner select icon  18  as illustrated in  FIG. 3 . The controller  26  will slowly increase the flame height to the maximum and then, in one embodiment, slowly decrease the flame height to the minimum.  
         [0023]     In an alternate embodiment, selection of the icon  18  when the burner  14  is already ignited will result in the controller  26  turning off the burner  14 . In this embodiment during operation, if the user wishes to extinguish the flame at a particular burner  14 , the user would simply touch the appropriate burner icon  18 . Once the capacitive touch interface  12  has detected the user&#39;s touch at this icon  18 , electronic controller  26  will operate the variable flow gas valve  22  to terminate flow of gas and extinguish the flame at that burner  14 .  
         [0024]     Programmed operation of the flame height is also available via the electronic controller  26 . While not illustrated in  FIG. 1 , other burner control icons, buttons, knobs, etc. are provided in alternate embodiments that relate to preset flame heights or gaseous fuel flow to the burner, e.g. simmer, low, medium, high, particular temperature settings, keep warm, gentle, delicate, etc. The controller  26  drives the variable flow gas valves  22  to the corresponding presetting of gas flow when one of these icons are selected.  
         [0025]     In one embodiment, the variable flow gas valves  22   A ,  22   B ,  22   C  or  22   D  may be the variable flow gas valves described in PCT International Application No. PCT/NZ2005/000135 entitled “Variable Flow Valve”, and in co-pending U.S. patent application Ser. No. 11/507,107 entitled “Variable Flow Valve,” the teachings and disclosure of which are hereby incorporated by their entireties by reference thereto.  
         [0026]     All references, including publications, patent applications, and patents cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.  
         [0027]     The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) is to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.  
         [0028]     Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. For example, such alternate embodiments may include other gas appliances such as clothes dryers where the variable gas flow burner control may better regulate the drying temperature than current burner on or off systems. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.