Patent Abstract:
The present invention is an improved electronic oven; a tabletop, or toaster oven that contains a vertically moveable heating element. The moveable heating element allows a range of foods and/or portions of food to be cooked or heated in the most efficient manner possible, saving time and energy use. A heat directing plate disposed above the moveable heating element further increases efficiency by directing heat onto the food.

Full Description:
CLAIM OF PRIORITY 
     This application is claiming the priority of the U.S. Ser. No. 61/276,718 filed on Sep. 16, 2009, of the U.S. Ser. No. 61/284,180 filed on Dec. 14, 2009, of the U.S. Ser. No. 29/348,248 filed on Dec. 14, 2009, of the Chinese Serial No. 200920157037.X filed on May 27, 2009, and of the Chinese Serial No. 2009301875388 filed on Apr. 28, 2009, the contents of which are fully incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to the field of electric ovens, in particular to tabletop or toaster ovens. 
     BACKGROUND OF THE INVENTION 
     Table top, or toaster ovens have become popular home appliances in many households. One reason is because using a toaster oven saves energy since it takes less energy to heat a smaller oven cavity than a standard wall oven, and the toaster oven can heat up more rapidly, thus decreasing cooking time. One limitation of a tabletop oven in relation to a full size wall oven is the fixed distance between the baking rack or tray and the heating element; in a wall oven, the baking rack is adjustable, so the food can be placed as close to the heating element as desired. If the toaster oven were engineered such that the position of the heating element relative to the baking tray could be adjusted so that the food is closer to the element, the baking time could be decreased and less power could be used, particularly when thinner food such as bread is cooked. The present invention may also preferably include a heat directing plate, which reflects heat from the heating elements back toward the food item, thus maximizing energy efficiency by minimizing heat dissipation. 
     Another advantage of a moveable heating element is that the user does not have to open the oven to get the food closer to the heat, as when a baking rack is moved. Further, a moveable heating element provides a measure of safety in that the user can move the heating element close to the food for cooking, then move the heating element away from the food when the food is removed from the electronic oven, thereby reducing the possibility of being burned by the heating element. 
     Attempts have been made to design more efficient tabletop and toaster ovens. Art in this area is described below. 
     U.S. Pat. No. 6,250,214 discloses an enclosed rotisserie with added convenience, including a countertop resting box-like enclosure housing a safety rear mounted heating element and a power rotated dual rod spit assembly. The gear driven spit assembly may be easily inserted and removed straight into and out of the enclosure without need for angling or coupling the assembly to a power drive socket. The spit assembly may also be mounted at various distances from the heating element to decrease cooking times. The open front of the enclosure is from time to time covered by an inclined glass panel door which may be opened in various ways to facilitate food insertion into and removal from the enclosure, and which may be easily removed for cleaning or other purposes. The embodiment&#39;s design makes efficient use of valuable counter space by recessing back and raising off the countertop its controls. Two countertop supported sizes for the embodiment are suggested, one for larger families and entertaining, and the other for small families and singles. Maintenance is minimized by various embodiment parts being removable for cleaning including a cleaning shield located behind the heating element, the glass door, and a drip pan with slotted cover. A variety of foods may be cooked using the spit and accessories that attach to the spit. Such accessories include wire baskets and a rotating stir fryer. Self-rotating kabob rods cook kabobs on all sides evenly and allow for increasing rotisserie capacity by increasing the length of rotating rods available for rotisserie food mounting. 
     U.S. Pat. No. 7,105,778 describes A combination toaster oven and toaster appliance for cooking and heating foodstuff including a housing defining a food cavity therein and a heating element mounted in the housing for heating the food cavity. The housing includes a top wall and a front wall. A slot is located in the top wall and a door is movably mounted to the front wall. A toaster oven opening is located in the front wall and provides access to the food cavity. The door is movable between a closed position wherein the door covers the toaster oven opening and an open position wherein the door exposes the toaster oven opening and food cavity. A slot cover is movable between an extended position covering the slot and a retracted position exposing the slot. 
     U.S. Pat. No. 7,317,174 describes a food heating or cooking appliance that has at least one electrical heating element within its interior that is adjustable in position so as to be able to be moved close to thin or small food items under the control of a manually actuated control. A separator plate that extends across the interior chamber of the appliance from side to side and from front to back is movable with the heating element to enable adjustment of the volumetric size of the cooking chamber containing the heating element and the food to be heated or cooked. A manual actuator, a knob or lever, for example, moves the heating element and the separator plate through a motion transfer bar that extends across the width of the appliance and is attached to a linkage on each side of the appliance to communicate movement to a pair of movable supports supporting the rod-like heating element at each of its ends and the separator plate at opposite edges. 
     The present invention has advantages the prior art lacks. It can cook a greater variety of foods than inventions detailed in some of the examples of the prior art above. The mechanism for moving the heating element in the present invention is elegant in its simplicity, making the present invention easier to maintain, less expensive to manufacture, and easier to use than examples in the prior art. 
     In the closest prior art, U.S. Pat. No. 7,317,174, the mechanism contains a number of moving parts including a slide bar that can easily jam or bend. In one embodiment of the present invention, the scissoring mechanism yields a fluid, smooth movement that can be stopped with the heating element at any position in the electronic oven body. 
     In both embodiments of the present invention, the interactive connecting rods are larger and sturdier than the mechanism of the prior art. This allows more force to be applied to the mechanism in a more symmetrical manner, which allows for smoother movement of the mechanism and the heating element than do the smaller slide bars of the prior art. Additionally, the present invention contains stabilizing rods to keep the support and mechanism stable as the heating element moves up and down. 
     In a preferred embodiment of the present invention, an ingenious interlocking vertical track and interlocking mechanism add great stability to the invention. None of the prior art discloses this interlocking mechanism, and it is believed that this is a novel mechanism. 
     Another feature of the present invention is that the control knob is connected to a cam mechanism that has multiple preset positions in a preferred embodiment. This increases safety as it also helps keep the heating element in place. 
     The present invention is an electric oven that has a moveable heating element and a top reflector plate such that the volume of heated space inside the oven is minimized yet is sufficient to cook the desired food. 
     The invention is an article of manufacture, an electric oven having a body for holding food, with at least one heating element within the body; vertical side slots installed symmetrically on a right side wall and a left side wall of the body with a terminal to connect the heating element to a mechanism art the vertical side slots; and a mechanism that drives movement of the heating element in the vertical direction along the vertical side slots. 
     The mechanism includes a lifting unit, which in one embodiment is a diamond shaped frame formed by four interactive connecting rods. Two upper interactive connecting rods form the top section of the diamond and are connected with the support, which may be a horizontal bar, and two lower inactive connecting rods form the bottom section of the diamond, and are connected to the revolving shaft that passes horizontally through the oven wall at the bottom of the left and right side walls of the body. The diamond shaped frame uses components, including but not limited to, pins, hinges, or joints at the intersection of the interactive connecting rods to connect them and also allow them to move in a pivoting action when an adjustable knob is turned and the revolving shaft is activated. 
     The connecting section of the revolving shaft is square and the corresponding hole of one of the lower interactive connecting rods is square to avoid slip, while the corresponding hole of the other lower interactive connecting rod is round. When the revolving shaft is rotating, the interactive connection rod with the corresponding square hole will be driven so that the interactive connection rod linked to it will be driven upward or downward, and, as a result, upward or downward movement of the heating element will be achieved. An adjustable knob is installed at the outer side wall of the electric oven, with the revolving shaft connected to it so that the motion of the shaft, and therefore the position of the heating element, can be controlled by a user. 
     When the knob is turned to the ‘low’ position, the four rods are in the collapsed position; when the knob is turned to the ‘high’ position, the four rods are in the extended position. The knob can be set so that the heating element stops at any of four points; in an alternate embodiment the heating element can be set at any interval between the high and low positions. 
     The mechanism is disposed on both the left side and the right sides of the electric oven, with identical elements of the mechanism on both sides except for the adjustable knob, which is disposed on only one side of the electric oven. In a preferred embodiment, the mechanism is concealed by an outer wall, so that is disposed between an inner and outer oven wall, and is not visible unless the oven is disassembled. Disposing the mechanism on both the right and left sides of the electric oven adds to the stability of the heating element in any vertical position. A spring may also be disposed on the mechanism to add stability and safety. In addition, there are stabilizing rods located on each side of the electric oven that stabilize and smooth the movement of the heating element. 
     In order to heat food more quickly, a heat reflecting plate may be disposed above the heating element to reflect heat down onto the food. The heat reflecting plate is disposed such that it moves with the heating element, by affixing it to one or more sides of the heating element. Alternately, the heat reflecting plate may move independently of the heating element. 
     A second embodiment of the invention is an article of manufacture that is an electric oven having a body for holding food with a vertically moveable heating element; an L-shaped lifing unit with a lower interactive connecting rod and an upper interactive connecting rod; an attached spring connected to a support bar that traverses vertical tracks; and a terminal to connect a heating element to the lifting unit. 
     The present invention is an improvement over the prior art because it has a design that is versatile, yet less complicated and therefore easier and less expensive to manufacture. 
     It is an object of the invention to provide a faster cooking method for small volumes of food. 
     It is an object of the invention to use less energy for cooking food. 
     It is an object of the invention to provide a means to adjust the volume of space that must be heated to cook food. 
     It is an object of the invention to provide a tabletop electric oven with an adjustable heating element. 
     It is an object of the invention to provide a tabletop electric oven with a heat reflecting plate above the upper heating element. 
     It is an object of the invention to provide a tabletop electric oven with an adjustable heating element that is easy to use. 
     It is an object of the invention to provide an improved mechanism for adjusting the height of the heating element in a tabletop electric oven. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front view of the invention. 
         FIG. 2  is a front view of the invention. 
         FIG. 3  is a front view of the invention. 
         FIG. 3A  is a top perspective view of the heat directing plate 
         FIG. 3B  is a side view of the heat directing plate. 
         FIGS. 3C and 3D  are top and bottom view of the heat directing plate. 
         FIG. 3G  is a view of dual racks 
         FIG. 3H  is another view of the dual racks that are used to bake Panini bread. 
         FIG. 3I  is a top view of a rack with pocket indentations for sandwich grilling. 
         FIG. 3J  is a top view of a rack with square indentations for waffle making. 
         FIG. 4  is a side view of one embodiment of the invention. 
         FIG. 5  is a side view of one embodiment of the invention. 
         FIG. 6  is a side view of an alternate embodiment of the invention. 
         FIG. 7  is a side view of an alternate embodiment the invention. 
         FIG. 8  is a side view of an alternate embodiment the invention. 
         FIG. 9  is a side view of an alternate embodiment the invention. 
         FIG. 10  is an exploded view of the gear portion of the invention. 
         FIG. 11  is a side view of an alternate, preferred embodiment of the invention. 
         FIG. 12  is an exploded view of the embodiment of  FIG. 11 . 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIGS. 1-3  are front views of a preferred embodiment of the invention.  FIG. 1  shows the heating element in the topmost position in the electric oven with the food tray at the bottom of the electric oven,  FIG. 2  shows the heating element in a lower position with the food tray at the bottom of the electric oven, and  FIG. 3  shows the heating element in the middle of the oven with the food tray raised to a higher position in the oven. 
       FIG. 1  is a front view of a preferred embodiment of the invention.  FIG. 1  shows electric oven  100 , with electric oven body  110 , which is also known as the body for holding food, electric oven door  120 , electric oven bottom  130 , electric oven top  140 , food rack  150 , food rack positioning tabs  155 , heat setting  160 , time setting  170 , temperature setting  180 , heating element  190 , adjustable knob  200 , outer side wall  210 , inner side wall  220 , right side wall  230 , left side wall  240 , and revolving shaft  400 . 
       FIG. 1  illustrates the configuration of the invention in the manner that a typical toaster oven or tabletop oven is used; the heating element  190  is at the very top of the oven body  110 , and the food rack  150  is at the bottom of the inside of the oven. There may also be a heating element  190  under the food rack, and there may be a tray that fits onto the food rack. The food rack  150  can be any shape or size, but is preferably flat to increase the versatility of the space usage in the oven body  110 . The revolving shaft  400  may be inside the oven body  110 , or anywhere outside the oven body  110 , as long as it is linked to the adjustable knob  200  and the lower interactive connecting rod. The food rack  150  and any optional food tray may be made from any material that can withstand heat, including but not limited to, metals, plastics, rubbers, or glass or combinations or composites of these or any other materials. 
       FIG. 2  is a front view of a preferred embodiment of the invention.  FIG. 2  shows electric oven  100 , electric oven body  110 , electric oven door  120 , electric oven bottom  130 , electric oven top  140 , food rack  150 , temperature setting  160 , time setting  170 , function setting  180 , heating element  190 , adjustable knob  200 , outer side wall  210 , inner side wall  220 , right side wall  230 , left side wall  240 , and revolving shaft  400 . 
       FIG. 2  illustrates the invention being used with the heating element  190  in the center of the electric oven body  110 , with the food rack  150  at its lowest position in the oven body  110 . This configuration is used when a small, thin food is being cooked or when bread is being toasted. 
     Shown in  FIGS. 3A-3D  is a preferred embodiment of the present invention in which the upper heating element  190  is connected to a heat directing plate  700 , with the heat directing plate  700  situated above the upper heating element  190  so that it directs heat down onto the food. This embodiment would allow an even faster cooking or browning of food. The heat directing plate may be made of any material, including but not limited to, metals, glass, plastics, rubbers, and it may be any shape desired. The preferred material is metal and the preferred shape is rectangular. In the preferred embodiment of the present invention, the upper heating element  190  is vertically movable, meaning it is capable of moving down towards oven bottom  130 , or up towards oven top  140 . 
     Shown in  FIG. 3A  is a perspective view of the heat directing plate  700 . Also shown are a top surface  710 , a bottom surface  715 , a convex curvature  720 , a concave curvature  730 , a sliding terminal  740 , an attachment point  750 , a front of the heat directing plate  760 , a front flap  765 , a back of the heat directing plate  770 , additional mount points  780 . 
     The upper heating element  190  may be disposed between two parallel sliding terminals  740 , or it may be disposed on a separate attachment. Preferably, the sliding terminals  740  may also serve as terminals for the upper heating element  190  and function as an insulated conductor of electric current between the wiring disposed in the body  100  and the upper heating element  190 . In such embodiment the sliding terminals  740 , or simply terminals, would double as a heating element terminal  380 . The sliding terminals  740  may be attached within attachment points  750 , which may be slide-in or snap-in tabs and slots, or they may be permanently fastened, glued, welded or riveted into place. Additional mount points  780  may be present to provide a strong and durable engagement between the sliding terminal  740  and the heat directing plate  700 . The sliding terminals  740  would travel vertically within the vertical side slots  300 , and connect directly or indirectly to a support arm  370  or  375 . 
     The surface of the heat directing plate  700  is preferably contoured, as shown in  FIGS. 3A and 3B . The contours provide for a substantial encirclement of the upper heating element  190  and thus increase the benefit and efficiency of the present invention. The convex surface  710  is a result of the fact that the heat directing plate  700  is preferably thin, to reduce weight, but is otherwise not needed. As shown in  FIGS. 3A and 3B  the upper heating element is disposed inside the cavity  735  that is formed by the convex surface  730 . The concave surface  730  may additionally be of a highly reflective and heat resistant material, such as brushed steel or a stainless steel, so as to reflect as much heat as possible. The heat radiated by the upper heating element  190  and the lower heating element  195  gets trapped by the bottom surface  715 , and specifically within the concave surface  730 , and is reflected back towards the area between the two heating elements  190  and  195 , thus magnifying the heat exposure of a food item disposed there between. 
     The design of the heat directing plate  700 , which may also be known as the reflector plate, is such that it has several included surfaces that coincide with the heating element and are radiused in such a way as to optimize the reflective properties of the radiated heat to the cooking area. For optimal output of the present invention, it may be preferable to lower the upper heating element  190  and the heat directing plate  700 , so that the food becomes encapsulated between the top and bottom heating elements  190  and  195 , or at equal distances between them. This setting creates a much greater heating/roasting/broiling/toasting efficiency due to its unique shape, design and properties. 
       FIGS. 3C and 3B  show top the heat directing plate  700 , the top surface  710 , the bottom surface  715 , the convex and concave curvatures  720  and  730 , sliding terminals  740 , an attachment point  750 , a front of the heat directing plate  760 , a front flap  765 , a back of the heat directing plate  770 , additional mount points  780 . The front flap  765  preferably contains a cautionary message for a user of the present invention. The message is recommended since at the time when the heat directing plate  700  is substantially lowered, the top surface  710  becomes exposed to view, which may result in someone being tempted to place food items upon it. In an alternative embodiment, the top surface  710  may also be used in food preparation; for example, for gentle heating of delicate food items. The heat directing plate  770  may be removable for cleaning or repair, or may be permanently affixed into place. 
     Illustrated in figs is the preferred embodiment of the lifting unit that serves as a mechanism for raising and lowering the upper heating element  190 . The preferred lifting mechanism for the lifting unit is a series of interlocking gears or a gear system. Specifically, the mechanism preferably is made up of a lower interactive connecting gear and at least one upper interactive connecting gear, with the lower interactive connecting gear preferably connecting to the adjustment knob  200 . The adjustment knob  200  may connect to a rotating shaft  400  that traversed the body of the oven  100 , and supports a lifting unit on the opposite side for a uniform and even vertical motion. 
     Furthermore, with the gear system design of the lifting unit  320 , the top heating element  190  may be capable of locking into place in a multitude of positions between the top most position, which is near the top of the oven  140 , and the bottom most position, which is near the bottom of the oven  130 . The locking is achieved through a friction lock, whereby the mechanism is under friction and when released tends to stay in the set position until moved again. Such mechanism is especially preferred here, since it is capable of functioning as a safety backup, in case an actual lock accidently or deliberately fails to engage, a friction lock is likely to still prevent the upper heating element  190  from falling onto an inserted body part, while the upper heating element  190  is still hot. 
     The preferred lifting mechanism embodied in a gear system represents a significant improvement over prior art due to its smooth operation, requiring uniform effort to raise and lower the lifting unit no matter where the heating element  190  may be located in the oven  100 ; but more importantly, it is safer due to the presence of a friction lock, since such a lock may always hold the hear mechanism in check. Additionally, an actual or true lock may be present in an embodiment of the present invention. 
     A mechanism may be a combination of gears, such as, but not limited to, spur gears, helical gears, double helical gears, bevel gears, hypoid gears, crown or worm gears, non-spherical gears, as well as rack and pinion mechanisms or sun and sphere mechanisms or any other combination of gears. Preference may be given to gear mechanisms that are especially known for increased friction between gear wheels, such as a worm gear or a helical gear. However, any other gear mechanism or a combination of gears with different mechanisms may be used, and friction may be increased or decreased by calibrating the interference, depth of engagement or interference of interlocking teeth with other, or adjusting any other variables that impact the frictional coefficient of the overall gear mechanism. 
     In an embodiment utilizing a worm or a rack and pinion gear combination, or any other gear combination, for the lifting unit mechanism  310 , the lifting unit  320  may have the pinion wheel or gear wheel connected to the adjustment knob  200  either directly or through intervening gear wheels. The pinion or gear wheel would then act on a worm or rack rail gear that may be attach perpendicularly to the horizontal support  375 . However, any other configuration of gears may achieve the same or similar preferred results. As such our unit  100  can boast a top heating element  190  that glides through several positions in which it can be retained or “locked” into any of these positions, the preferred minimum number of adjustable positions is set at three; however, a gear mechanism may make the number of positions adjustment close to infinity or at least between two and twenty different settings. 
     A preferred gear mechanism may contain a true locking function of the upper heating element  190 . One example of a true locking function would be a pin to the gear system, for example that would engage the gears and prevent them from any rotation until the pin is removed. The pin could be removed by an actuator button or lever which would need to be simultaneously pressed or activated while turning the knob to adjust the top heating element. Although not shown, the height of the lower heating element  195  may also be made adjustable, either separately or in concert with the upper heating element  190 , using the same or different mechanism. 
       FIG. 3  is a front view of a preferred embodiment of the invention.  FIG. 3  shows electric oven  100 , electric oven body  110 , electric oven door  120 , electric oven bottom  130 , electric oven top  140 , food rack  150 , food rack positioning tabs  155 , heat setting  160 , time setting  170 , temperature setting  180 , heating element  190 , adjustable knob  200 , outer side wall  210 , inner side wall  220 , right side wall  230 , left side wall  240 , and revolving shaft  400 . 
       FIG. 3  illustrates the food rack  150  suspended in the food rack positioning tabs  155 , with the heating element  190  just above the food. This configuration is used when one desires more flow around the bottom of the food, or if there is a bottom heating element  190  and one prefers the top of the food to be browned or to be cooked faster than the bottom of the food. 
       FIGS. 3G-3J  illustrate the versatility of the present invention. Shown in  FIGS. 3G and 3H  is an embodiment of the oven  100  having at least 2 racks  150 , that may also be referred to as removable racks, since they may are preferably easy to remove for cleaning or repair. The racks  150  may be supported by the food rack positioning tabs  155  or secured directly within slots in the inner sidewalls  220 . At least two racks may be needed to prepare an increased number of foods, or to shield a lower food item with an upper food item, such as when a lower food item may have a delicate nature. Another reason for using more than one rack to leave a desirable grill marking on the food item, for example on meets, vegetables, or breads. The dual racks  150 , as shown in  FIGS. 3G and 3H  may be used to bake or grill Panini style bread, or any bread. Both the upper rack  150 U and the lower rack  150 L may be adjustable to fully enclose or reveal the food item  150 B. 
     Also shown in  FIGS. 3G and 3H  is an instrument panel  185 , a having heat setting  160 , a time setting  170 , a temperature setting  180 , an adjustable knob  200 , an outer side wall  210 , an inner side wall  220 , a right side wall  230 , a left side wall  240 , and an indicator light  186 . The indicator light  186  may also contain, or may alternatively function as, a light sensor. As a light sensor the indicator  186  may perceive when a light has been turned off, to either, or both, sound an alert or turn off the heating elements  190  and  195 . This may be an added safety or efficiency feature so that the oven  100  should not be “forgotten” in an ON state or with food items still inside. In yet another alternative, such a sensor may be overridden, which may also be set to specific time duration. 
       FIGS. 3I and 3J  illustrate some of the trays  156  that may be used with the oven  100 . Alternatively, these may be racks  150 . The difference is that a tray  156  is supported by a rack  150 , or directly by the food rack positioning tabs  155 . Illustrated in  FIG. 3I  is a sandwich tray  156 S and in  FIG. 3J  a waffle tray  156 W. The trays  156  also have a front tab  158  for securely holding and handling the tray  156 . The tab preferably faces the oven door  120  for easier access and egress of the trays  156 . 
     As seen in  FIGS. 3G and 3H , the racks  150  are preferably in a parallel and cooperating orientation to each other. This means that the racks  150  are preferably opposite each other and stacked on the same plane. It may also be preferable that the surfaces of the racks  150  that face each other have corresponding curvatures, bars or indentations, so as to create a pinching effect on food items. This may serve to create grill lines and it may further facilitate the swiftness of food preparation made possible with the present invention. Similarly, the trays  156  may have cooperating and corresponding surfaces and surface features. Alternatively, a tray  156  may be strapped (not shown) unto the upper rack  150 U with another tray placed unto the lower rack  150 L. The racks  150 U and  150 L may then be brought together until the opposite trays pinch or encapsulate a food item. Other types of trays  156  or plates may be utilized, such as, but not limited to a grill plate, Panini plate, bread plate, pocket plate, or a waffle plate, or any combination thereof, or any other type of a plate, tray or rack. 
     The sides of the rectangle may be angled down to form a type of hat to further increase heat direction toward the food. The heat directing plate  700  may be one piece or may consist of multiple pieces. If multiple pieces are employed, the pieces may be joined in any effective manner. 
       FIGS. 4 and 5  are side views of one embodiment of the invention.  FIGS. 4 and 5  illustrate the alternative embodiment of a mechanism  310  for moving the upper heating element  190 . A reference to a heating element should be taken to mean the upper heating element  190 , unless other wise stated.  FIG. 4  shows the mechanism  310  when the heating element  190  is in the center of the electric oven body  110 , and  FIG. 5  shows the mechanism when the heating element  190  is at the top of the electric oven body  110 . 
       FIG. 4  is a side view of the invention that shows a detailed view of the mechanism  310  used to move the heating element  190 .  FIG. 4  shows electric oven  100 , electric oven bottom  130 , electric oven top  140 , adjustable knob  200 , outer side wall  210 , vertical side slot  300 , stabilizing rod  305 , mechanism  310 , lifting unit  320 , diamond shaped frame  330 , upper interactive connecting rod  350 , lower interactive connecting rod  360 , support  370 , heating element terminal  380 , spring  390 , and revolving shaft terminal  410 . 
       FIG. 5  is a side view of the invention that shows a detailed view of the mechanism  310  used to move the heating element  190 .  FIG. 5  shows electric oven  100 , electric oven bottom  130 , electric oven top  140 , adjustable knob  200 , outer side wall  210 , vertical side slot  300 , stabilizing rod  305 , mechanism  310 , lifting unit  320 , diamond shaped frame  330 , upper interactive connecting rod  350 , lower interactive connecting rod  360 , support  370 , heating element terminal  380 , spring  390 , and revolving shaft terminal  410 . 
     The mechanism  310  operates in the following manner. A user turns the adjustable knob  200 , which is connected to the revolving shaft  400 . The revolving shaft  400  is connected to a lower interactive connecting rod  360  of the diamond shaped frame  330 . The revolving shaft  400  drives the lifting unit  320 , so that if the user wishes to raise the heating element  190 , the diamond shaped frame  330  is forced upward when the user turns the adjustable knob  200  to the ‘upper’ position. 
     The heating element  190  is connected to the support  370  through the heating element terminal  380  at the top of the diamond shaped frame  330 , therefore it is forced upward when the diamond shaped frame  330  and support  370  are forced upward. The heating element  190  slides through the vertical side slots  300  when it moves upward, so that force exerted on the outside of the electric oven is transferred to the heating element  190  inside the electric oven. The stabilizing rods  305  keep the support stable and horizontal as it moves. One or more heating elements may be used, or the heating element may have one or more horizontal sections. As shown in the figures, the heating element  190  has two horizontal sections, and is connected to the support  370  through both. 
       FIGS. 6 and 7  are side views of another alternate embodiment of the invention. They show the embodiment of  FIGS. 4 and 5  with a spring  390  added to the diamond shaped frame  330 ; some numbering has been left off of  FIGS. 6 and 7  for clarity. The spring  390  adds stability to the mechanism  310 . 
       FIG. 6  shows the invention with the heating element  190  in the center of the inside of the electric oven  100 , electric oven bottom  130 , electric oven top  140 , outer side wall  210 , diamond shaped frame  330 , and spring  390 . 
       FIG. 7  shows the invention with the heating element  190  at the top of the inside of electric oven  100 , electric oven bottom  130 , electric oven top  140 , outer side wall  210 , diamond shaped frame  330 , and spring  390 . 
       FIG. 8  is a side view of an alternate preferred embodiment the invention with the heating element  190  in the center of the electric oven  100 , electric oven bottom  130 , electric oven top  140 , adjustable knob  200 , outer side wall  210 , vertical side slot  300 , stabilizing rod  305 , mechanism  310 , lifting unit  320 , upper interactive connecting rod  350 , lower interactive connecting rod  360 , support  370 , heating element terminal  380 , spring  390 , revolving shaft terminal  410 , L-shaped lifting unit  500 . 
       FIG. 9  is a side view of an alternate preferred embodiment the invention with the heating element  190  at the top of the inside of the electric oven  100 , electric oven bottom  130 , electric oven top  140 , adjustable knob  200 , outer side wall  210 , vertical side slot  300 , stabilizing rod  305 , mechanism  310 , lifting unit  320 , upper interactive connecting rod  350 , lower interactive connecting rod  360 , support  370 , heating element terminal  380 , spring  390 , revolving shaft terminal  410 , L-shaped lifting unit  500 . 
     In this preferred embodiment, there is an L-shaped lifting unit formed from an upper interactive connecting rod  350  connected to the support  370 , and a lower interactive connecting rod  360  connected to a spring  390 , the adjustable knob  200 , and the revolving shaft terminal  410 . A spring  390  is attached at the union of the two interactive connecting rods. The support  370  is connected to the heating element  190  as in the previous embodiment, ( FIGS. 4-7 ), the lower interactive connecting rod  360  is connected to the revolving shaft shown in  FIGS. 1-3 , and the heating element  190  traverses the vertical side slots  300  to move up and down within the electric oven  100 . The heating element  190  height may be adjusted to be employed at any vertical position inside the oven body. 
     This embodiment has the same configuration on both the right side wall and left side walls of the invention, except that the adjustable knob  200  is only present on one of the two sides. 
     The shape of the interactive connecting rods in this embodiment leads to a scissoring movement when the adjustable knob is turned to activate the revolving shaft. The scissoring movement makes the invention easier to use and maintain than specimens in the prior art, because there are fewer moving parts and it is a simpler, yet still effective, design that yields a fluid movement of the mechanism. 
     In one embodiment, there is a spring installed that connects the L-shaped lifting unit to the body. This adds stability and safety to the invention. 
       FIG. 10  is an exploded view of the gear portion of one embodiment of the invention.  FIG. 10  shows the gear  600 , with gear outer housing  610 , gear inner housing  620 , first gear setting  630 , second gear setting  640 , third gear setting  650 , gear locking mechanism  660 , and revolving shaft port  670 . The revolving shaft passes into the gear through the revolving shaft port  670 . 
     When the shaft is turned, the gear outer housing  610  stays stationary, while the gear inner housing  620  turns. The gear locking mechanism  660  flexes to allow movement of the gear inner housing  620 . When a gear setting (in  FIG. 10  the first gear setting  630 ), aligns with the gear locking mechanism  660 , the two components are locked together in a reversible manner. This provides stability for the heating element at a position determined by the gear setting. If a different heating element position is desired, the revolving shaft is turned and the gear locking mechanism  660  is locked together with a different gear setting. 
     In the embodiment illustrated in  FIG. 10 , the heating element can be moved to one of three positions corresponding to one of the three gear settings; the number of positions depends on the number of gear settings. Although the gear  600  is shown with three gear settings, it may have any number of gear settings, with a preferred number from of settings from one to 50, with the most preferred number of settings being three as shown in  FIG. 10 . 
       FIGS. 11 and 12  show a side view of an alternate, preferred embodiment of the invention.  FIG. 11  shows the entire side of the invention, and  FIG. 12  shows an exploded view of a distinguishing feature of this embodiment. This embodiment is similar to the embodiment shown in  FIGS. 8 and 9 , but has added features that improve stability and ease of use. 
       FIG. 11  shows the invention with the heating element  190  in the center of the inside of the electric oven  100 . Also shown are electric oven bottom  130 , electric oven top  140 , adjustable knob  200 , vertical side slot  300 , stabilizing rods  305 , upper interactive connecting rod  350 , lower interactive connecting rod  360 , support  370 , heating element terminals  380 , conductive cable  385 , spring  390 , L-shaped lifting unit  500 , vertical locking track  515 , interlocking mechanism  517 , first heating element position  530 , second heating element position  540 , and third heating element position  540 . 
     In this preferred embodiment, there is an L-shaped lifting unit formed from an upper interactive connecting rod  350  connected to the support  370 , and a lower interactive connecting rod  360  connected to a spring  390 , the adjustable knob  200 , and the revolving shaft terminal  410 . A spring  390  is attached at the union of the two interactive connecting rods. This adds stability to the system. The support  370  is connected to the heating element  190  as in the previous embodiments, ( FIGS. 4-9 ), the lower interactive connecting rod  360  is connected to the revolving shaft shown in  FIGS. 1-3 , and the heating element  190  traverses the vertical side slots  300  to move up and down within the electric oven  100 . 
     This embodiment contains added features for stability and ease of use. The upper interactive connecting rod  350  is connected to the support  370  and also to an interlocking mechanism  517  which traverses the vertical locking track  515 . 
       FIG. 12  shows an exploded view of the interlocking mechanism  517  and the vertical locking track  515 . Shown is electric oven  100 , stabilizing rods  305 , upper interactive connecting rod  350 , conductive cable  385 , vertical locking track  515 , interlocking mechanism  517 , notch  520 , spring coil  525 , and second heating element position  540 . 
     When the L-shaped lifting unit  500  and thus the heating element  190  is moved, the interlocking mechanism  517  moves with it up or down the vertical locking track  515 ; when the desired position is reached, the spring coil  525  in the interlocking mechanism  517  engages the notch  520  to keep the lifting assembly stable in the specified position. The tension of the spring coil  525  against the notch  520  keeps the L-shaped lifting unit and the heating element in place and adds stability to the invention that is not present in the prior art. 
     In this embodiment, there are three positions for the heating element  190  and three notches  520  to yield a first heating element position near the bottom of the electric oven  100 , a second heating element position near the center of the electric oven  100 , and a third heating element position near the top of the electric oven  100 . Although the preferred embodiment contains three positions for the heating element  190 , any number of positions may be employed, with any number of notches  520 . 
     This embodiment has the same configuration on both the right side wall and left side walls of the invention, except that the adjustable knob  200  is only present on one of the two sides. 
     The invention and any or all of its components may be made from any suitable material, including but not limited to, metals, glass or glass products, plastics, rubbers, wood or paper products, or any combination of the above or other materials. 
     The overall size of the invention may be from 10-30 inches long by 4-20 inches high by 5-25 inches in depth, with preferred dimensions of 18.35 inches long by 10.96 inches high by 14.22 inches in depth. 
     Although this invention has been described with a certain degree of particularity, it is to be understood that the present disclosure has been made only by way of illustration and that numerous changes in the details of construction and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention.

Technology Classification (CPC): 5