Abstract:
A system for heating and/or cooking food whose upper heating limit is adjustable. An energy setting assembly is provided with the system that includes a knob, a restrictor plate, and a limit pin. The limit pin is selectively inserted into openings formed along multiple locations in the restrictor plate, where the openings follow a generally curved path. The knob rotatably mounts over and is generally coaxial with the restrictor plate. Rotating the knob regulates heat output of the system. Web members are formed on the knob and that project in a radial direction from a receptacle in the knob. The web members come into interfering contact with the limit pin when knob is rotated to a designated orientation, so that strategically locating the limit pin, limits angular movement of the knob to the designated orientation, thereby limiting a maximum energy input to the system.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of Invention 
       [0001]    The present disclosure relates to a system for limiting input to a heating apparatus. More specifically, the present disclosure relates to a control system for adjusting a maximum setting for a cooking unit. 
       2. Description of Prior Art 
       [0002]    Systems for heating and/or cooking food typically generate thermal energy with a heating element powered by electricity or by combusting fuel. Example systems include ranges, stoves, ovens, grills, burners, hot plates, and the like. Control knobs are usually provided with the systems for regulating the amount of thermal energy produced by the systems when heating and/or cooking the food. While too much energy can overcook or burn the food, excess energy can also damage cookware, cook tops, or hardware associated with the cooking system, such as electrical components that control the systems. Moreover, too high a temperature can present a fire hazard; kitchen fires are the number one cause of home fires and home injuries. This hazard is especially present when oil is used for cooking, as oil can combust when exposed to a temperature that exceeds its flash temperature. Ranges or cooktops are responsible for almost six times as many fires than ovens, and electrically powered ranges present a higher risk of fires and associated losses than gas ranges. 
       SUMMARY OF THE INVENTION 
       [0003]    Disclosed herein is an example of an energy setting assembly for use with a food preparation system which includes a knob having a receptacle that selectively couples with an energy controller that regulates thermal output of the food preparation system, so that moving the knob moves the energy controller to selectively adjust thermal output of the food preparation system. Also included in this example are a web member coupled to and extending radially from the receptacle and that follows a path when the knob is actuated; a restrictor plate affixed to be stationary with respect to the knob, openings formed at different locations in the restrictor plate, and a limit pin having a portion protruding through a one of the openings and into the path of the web member, so that when the web member contacts the limit pin and blocks further movement of the knob, the energy controller regulates thermal output of the food preparation system to a designated value which is less than a maximum thermal output of the food preparation system. 
         [0004]    The restrictor plate can be made from a disk like member that includes a planar deck, and wherein the openings are formed through the deck. In this example the openings can be formed along a generally curved path along the deck. Optionally, a center portion of the deck is recessed and contains holes that receive fasteners for securing the restrictor plate to the food preparation system; and wherein a slot can be formed adjacent the holes. The limit pin can include a base that is generally planar and has a curved lateral surface and an upper surface, and a pin member that mounts to the upper surface, and wherein the pin member protrudes through the selective openings in the restrictor plate. The curved lateral surface of the base can correspond to an outer circumference of a recessed portion of the restrictor plate. The knob can include a base portion with curved sidewalls that define a cavity within in which the receptacle and web members are located, and wherein the limit pin protrudes into the cavity. The energy controller can be a rheostat or a control valve for regulating a flow of fuel to the food preparation system. The food preparation system can be an electric stovetop, a gas stovetop, an oven, a grill, or combinations thereof. 
         [0005]    Another example of an energy setting assembly for use with a food preparation system includes a restrictor plate having openings formed therethrough, and a knob that is rotatable with respect to the restrictor plate and that is for attachment to an energy controller that regulates a thermal energy output of the food preparation system, so that rotating the knob in turn rotates the energy controller and adjusts the thermal energy output of the food preparation system. The energy setting assembly of this embodiment also includes a web member in the knob, and a limit pin strategically inserted through a one of the openings in the restrictor plate, so that when the knob is rotated a designated amount, the web member is put into interfering contact against the limit pin, and energy controller is at an angular orientation which regulates the thermal energy output of the food preparation system to be at an amount that is less than a designated thermal energy output. The designated thermal energy output can be sufficient to heat an amount of cooking oil to a temperature that exceeds a flashpoint of the cooking oil. The openings can be formed along a curved path. In one example, the knob and restrictor plate are generally coaxial with one another. Optionally, an outer portion of the restrictor plate defines a ring, and which as a radius greater than a radius of the knob. In an alternative, the thermal energy output is from one of a burner or a heating element. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0006]    Some of the features and benefits of the present invention having been stated, others will become apparent as the description proceeds when taken in conjunction with the accompanying drawings, in which: 
           [0007]      FIG. 1  is a perspective exploded view of an example of an energy setting assembly for use with a cooking system. 
           [0008]      FIG. 2  is a perspective view of a lower surface of an example of a knob for use with the energy setting assembly of  FIG. 1 . 
           [0009]      FIG. 3  is a perspective overhead view of an example of a restrictor plate for use with the energy setting assembly of  FIG. 1 . 
           [0010]      FIG. 4  is a perspective view of a lower surface of an example of the restrictor plate of  FIG. 3 . 
           [0011]      FIG. 5  is a perspective view of an example of a cooking system having an example of the energy setting assembly of  FIG. 1 . 
       
    
    
       [0012]    While the invention will be described in connection with the preferred embodiments, it will be understood that it is not intended to limit the invention to that embodiment. On the contrary, it is intended to cover all alternatives, modifications, and equivalents, as may be included within the spirit and scope of the invention as defined by the appended claims. 
       DETAILED DESCRIPTION OF INVENTION 
       [0013]    The method and system of the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings in which embodiments are shown. The method and system of the present disclosure may be in many different forms and should not be construed as limited to the illustrated embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey its scope to those skilled in the art. Like numbers refer to like elements throughout. In an embodiment, usage of the term “about” includes +/−5% of the cited magnitude. In an embodiment, usage of the term “substantially” includes +/−5% of the cited magnitude. 
         [0014]    It is to be further understood that the scope of the present disclosure is not limited to the exact details of construction, operation, exact materials, or embodiments shown and described, as modifications and equivalents will be apparent to one skilled in the art. In the drawings and specification, there have been disclosed illustrative embodiments and, although specific terms are employed, they are used in a generic and descriptive sense only and not for the purpose of limitation. 
         [0015]    Shown in  FIG. 1  is a perspective view of an energy setting assembly  10 , and which is shown in an exploded view. The energy setting assembly  10  is used for adjusting an energy controller  11 , which as will be described in more detail below regulates an amount of energy to an associated food preparation system  12  ( FIG. 5 ); thereby affecting the thermal energy output of the food preparation system  12 . Energy controller  11  is shown having a stem  13  that when rotated alters the amount of energy to the associated food preparation system  12 . The energy setting assembly  10  includes a knob  14 , a restrictor plate  16 , and a limit pin  18 . The limit pin  18  includes a planar base  20  which has a generally oval shape; an upper surface  21  of the base  20  includes an elongate pin member  22  mounted thereon. 
         [0016]    In the example of  FIG. 1 , restrictor plate  16  is a generally planar member having a curved outer periphery and having a disk-like appearance. A series of openings  24  are shown axially formed through the restrictor plate  16 , openings  24  in the illustrated example are generally round and are formed along a curved path that is substantially concentric with the outer periphery of the plate  16 . Knob  14  includes a lower portion  26  which is shown having outer curved sidewalls and an upper surface  27  on which a ridge  28  is formed. Ridge  28  extends generally radially along the upper surface  27  and provides lateral surfaces for gripping the knob  14  so knob  14  can be rotated. 
         [0017]      FIG. 2  shows in a side perspective view a lower surface of knob  14 . Here, the outer sidewalls of lower surface  26  define a cavity  30  within the lower portion  26  and which is open to the outside of knob  14 . An annular receptacle  32  is attached to the body of the knob  14  which projects to within cavity  30 , and is formed to receive stem  13  from energy controller  11  ( FIG. 1 ). An optional key  34  is shown extending axially along an inner surface of receptacle  32 , and which may optionally mate with corresponding indentions within stem  13 . Accordingly, rotation of knob  14  can adjust settings of energy controller  11  and increase or decrease the electricity or gas flowing into food preparation system  12  thus controlling the thermal energy output of the food preparation system  12  and its corresponding temperature. Further shown in  FIG. 2  are web members  36 ,  38  that extend radially from an outer surface of receptacle  32  and into attaching contact with an inner surface of sidewalls of lower portion  26 . Web members  36 ,  38  of  FIG. 2  are illustrated as extending from a lower portion of cavity  30  and axially upwards to an upper section of the lower portion  26 . Thus the heights of the web members  36 ,  38  exceed their respective widths. Optionally, web members  36 ,  38  may simply be rods or pins, with approximately the same widths and heights, and disposed at the roughly the same angular positions around the outer surface of receptacle  32  as the web members  36 ,  38 . 
         [0018]      FIG. 3  shows in a downward perspective view an example of the restrictor plate  16 , and where restrictor plate  16  includes a planar deck  40  in its middle portion. Here the openings  24  are formed through the deck  40  and wherein the pin member  22  of limit pin  18  extends through one of the openings  24  to an upper surface of deck  40 . A ring  42  is shown circumscribing deck  40  and extending a radial distance outward from the higher periphery of deck  40 . Markings  43  are shown on the upper surface of ring  42  that can provide an indication of the heating levels of the food preparation system  12 . Thus rotating knob  14  ( FIG. 2 ) to align with a one of the markings in turn rotates stem  13  of energy controller  11  to a set orientation, which can deliver a designated amount of energy to the food preparation system  12 . Correlating the markings  43  with the orientation of the stem  43  provides for the designated amount of energy to the food preparation system  12  to be appropriate for whatever food is being prepared. An inner portion of deck  40  is shown having a recess  44  and projects downward from the rest of the surface of deck  40 . An inner recess  46  is shown having a generally clover leaf shape and defines an area that is recessed further from deck  40 . On adjacent clover leaves, openings  48 ,  50  are shown that extend axially through restrictor plate  16 . Openings  48 ,  50  can receive fasteners (not shown) for securing the restrictor plate  16  to food preparation system  12  so that the restrictor plate  16  is held stationary during operation; and so that the knob  14  can rotate with respect to restrictor plate  16 . Also shown in inner recess  46  is a slot  52  which extends axially through inner recess portion  46  and restrictor plate  16  has a generally L shaped configuration. Slot  52  receives screws (not shown) that mount into an underlying rheostat (such as the energy controller  11  of  FIG. 1 ). The configuration of slot  52  enables coupling restrictor plate  16  to rheostat without the need of removing screws that hold the rheostat in place. An advantage of the slot  52  is that with at least one screw holding the rheostat in place, the rheostat does not drop downward into the food preparation system  12  when trying to couple the restrictor plate  16  thereon. 
         [0019]      FIG. 4  shows in a perspective view a lower surface of the restrictor plate  16  and depicts how limit pin  18  projects through a lower side of restrictor plate  16 , and where base  20  provides a backstop so that the pin member  22  ( FIG. 3 ) extends from the upper surface of deck  48  a designated length. The length of the pin member  22  above deck  40  should be so that when the knob  14  is rotated a designated angular amount, one of the web members  36 ,  38  comes into interfering contact with the pin member  22 —thereby restricting the angular rotation of knob  14  to that angular amount. As such, the angular rotation of the stem  13  ( FIG. 1 ) is thereby also limited by setting the pin member  22  through a selected one of the openings  24  in the stationary restrictor plate  16  so that the energy supplied to the food preparation system is at an amount no greater than what is considered to be designated amount. By strategically disposing limit pin  18  into one of the openings  24 , that designated amount of thermal energy output can be set so that the corresponding temperature of any food being prepared is below that which can ignite what is being heated. Examples of such a temperature includes the combustion temperature of what is being cooked and a flash point of an oil used in food preparation. As shown, a number of openings  24  are provided so that the limit pin  18  can be set in any one of them, which provides significant flexibility in what thereby limiting the maximum amount of power that can be delivered to the food preparation system. 
         [0020]      FIG. 5  shows in a perspective view one example of the food preparation system  12  having an upper surface with burners  56  located thereon and includes an oven  58 . In the illustrated example, knobs  14  that are part of the energy setting assembly  10  of  FIG. 1  are provided on the food preparation system  12  and for controlling the thermal energy output of the burner  56  or oven  58 . As shown, this includes a door  60  with a glass portion  62 , through the glass portion  62  a heating element  64  is visible, which can be controlled via rotation of the knobs  14  that make up the energy setting assemblies  10  provided on the food preparation system  12 . Accordingly, the knob  14  for controlling power to the heating element  64  can have rotation that is limited by strategic setting of a limit pin  18  which is included with the energy setting assembly  10  associated with controlling the oven  58 . Similarly, energy setting assemblies  10  for controlling energy to one of the burners  56 , can also have designated settings of the limit pins  18  so that the thermal output of the specific burners  56  can be strategically adjusted. 
         [0021]    The food preparation system  12  can be an electric stovetop, a gas stovetop, an oven, a grill, or combinations thereof. In examples where the food preparation system  12  is electrically powered, the energy controller  11  can be a rheostat. In optional embodiments when the food preparation system  12  operates by combustion of fuel, the energy controller  11  can be a control valve for regulating a flow of fuel to the food preparation system  12 . In one non-limiting example of operation, the energy controller  11  ( FIG. 1 ) is mechanically limited by how much it can be actuated, for example in embodiments where the stem  13  is rotated, its angular rotation in a clockwise or counterclockwise direction is restricted. Further optionally, the angular orientations of the stem  13  when at its maximum allowed clockwise or counterclockwise rotation (which is referred to herein in one example as a maximum or minimum setting of the energy controller  11 ) correspond to minimum and maximum (or vice versa) levels of energy being directed to the food preparation system  12  and regulated through the energy controller  11 . In an embodiment a minimum level of energy to the food preparation system  12  is equivalent to an “off” setting so that no energy is being supplied to the food preparation system  12 . The maximum setting of the energy controller  11  (or stem  13 /knob  14 ) sometimes allows an energy output of the food preparation system  12  sufficient high to ignite cooking oil or exceed the combustion temperature of what is being prepared; and thus present a fire hazard. An advantage of the present disclosure is that this fire hazard can be avoided by selectively locating the limit pin  18  so that its pin member  22  projects through a particular one of the openings  24  in the restrictor plate  16 ; and anchoring the restrictor plate  16  so that the stem  13  is rotatable with respect to the restrictor plate  16 . With the restrictor plate  16  in place and pin member  22  extending past the deck  40  ( FIG. 3 ), the knob  14  is set over the restrictor plate  16  and the stem  13  inserts into the receptacle  32  ( FIG. 2 ). When the knob  14  (and stem  13 ) is rotated, which angularly displaces the web members  36 ,  38 , a one of the web members  36 ,  38  comes into interfering contact with the pin member  22 . The openings  24  are formed in the restrictor plate  16  at multiple locations; but along a path that is less than 3600, so that when the limit pin  18  is set into one of the openings  24 , the limit pin  18  limits the angular rotation of the knob  14  to an amount that is less than its maximum setting. Accordingly, strategically disposing the limit pin  18  so that the pin member  22  protrudes through a particular or designated one of the openings  24  at an angular location along the circular path on which the openings  24  are arranged, governs a maximum amount of energy that can be delivered to the food preparation system  12 , and thus can regulate the amount of thermal energy being applied to what is being heated with the food preparation system  12 . Strategically setting the limit pin  18  into a designated opening  24  prevents what is being cooked or heated with the food preparation system  12  from combusting or igniting. Moreover, with implementation of the energy setting assembly  10  onto a food preparation system  12 , a power output of the food preparation system  12  can be limited to an amount that is less than a maximum power amount of the food preparation system  12 . 
         [0022]    The present invention described herein, therefore, is well adapted to carry out the objects and attain the ends and advantages mentioned, as well as others inherent therein. While a presently preferred embodiment of the invention has been given for purposes of disclosure, numerous changes exist in the details of procedures for accomplishing the desired results. For example, the energy setting assembly is not limited to controlling energy for food preparation systems, but can be used in conjunction with any knob or handle that when adjusted controls an associated flow. Example controls include knobs that control a flow of fluid, where the fluid can be a gas or liquid, and where the fluid can be hot or cold. Other controls include mixing valves, such as for mixing together fluids of different temperatures so that the fluid exiting the valve is does not extend past a designated temperature or flow rate. These and other similar modifications will readily suggest themselves to those skilled in the art, and are intended to be encompassed within the spirit of the present invention disclosed herein and the scope of the appended claims.