Counter-top electric cooker

Information

  • Patent Grant
  • 6201217
  • Patent Number
    6,201,217
  • Date Filed
    Monday, April 12, 1999
    25 years ago
  • Date Issued
    Tuesday, March 13, 2001
    23 years ago
Abstract
A counter-top electric oven is provided that includes a number of features that prevent overheating of the components of the oven. These features include an actively cooled fan chamber, a hot gas vent, a cooling manifold that directs cooling air to cool the cooking enclosure and hot gas vented from the hot gas vent, and a base with thermally insulated supports for a metallic oven pan of the cooking enclosure.
Description




FIELD OF THE INVENTION




This invention relates to electric ovens, and in particular to counter-top electric cook ovens.




BACKGROUND OF THE INVENTION




Counter-top electric ovens are known in the art. In comparison to conventional ovens, counter-top electric ovens typically offer the advantage of being less bulky and having quicker cooking times. It is common for counter-top ovens to include a power head having a heating unit that is used to heat the cooking enclosure. It is also common for the interior of the cooking enclosure in such ovens to be accessed by manually lifting an upper portion of the cooking enclosure from the remainder of the cooking enclosure. To reduce the weight of counter-top electric ovens for portability and to provide a cooking enclosure that allows viewing of the cooking operation, counter-top electric ovens typically utilize plastic materials for a majority of their housings, including for the cooking enclosure. To reduce the cooking time, counter-top electric ovens typically will rely on a hot air stream that is cycloned around the food by a high speed fan associated with the electric heating element, or by utilizing an infrared heating element in combination with a relatively low speed fan that generates sufficient air circulation in the oven to ensure a relatively uniform temperature distribution in the oven. One example of a counter-top electric oven that utilizes an infrared electric heating element, a relatively low speed fan, and plastic housings, is disclosed in U.S. Pat. No. 5,404,420 issued Apr. 4, 1995 to Eugene Song.




One problem associated with such ovens is the heat generated by the heating unit of the power head. This heat can potentially damage plastic components of the oven and can also potentially increase the temperature of the oven housings to a point where a user cannot comfortably access the cooking enclosure. This problem is especially of concern for the components and housing near the heating unit.




As seen in the Song patent, it is also known for the lower portion of the cooking enclosure of such ovens to be defined by a metallic pan having an interior surface at which the heat generated by the heating unit is directed. The metallic pan is supported and surrounded by a plastic base which prevents the heat transmitted from the metallic pan from damaging the counter-top on which the oven is resting. One problem associated with this construction is that the metallic plate can transfer sufficient heat from the heating unit to damage housing components contacting the pan, or can transfer sufficient heat surrounding the housing to a point where a user cannot comfortably touch the surrounding housing. Another problem associated with this construction is that it can be very difficult to remove the metallic pan from the base, especially when the metallic pan is hot.




Other concerns common to counter-top ovens are the assembly and disassembly of the housings to allow the insertion and removal of food for cooking, and the cleaning of the interior of the cooking enclosure and the heating components therein.




SUMMARY OF THE INVENTION




It is the principal object of the invention to provide a new and improved counter-top electric oven.




It is another object of the invention to provide a new and improved counter-top infrared electric oven.




It is another object of the invention to provide a counter-top electric oven that minimizes the risk of heating housing components to a point where the components can be damaged or where a user cannot comfortably handle the housings during operation or soon after operation has been terminated.




An exemplary embodiment of the invention achieves at least some of the foregoing objects in a counter-top electric oven for cooking food that includes a cooking enclosure and a power head detachably connected to the cooking enclosure. The cooking enclosure includes an upper surface with an opening therein. The power head includes a heating unit extending into the cooking enclosure through said opening, a fan chamber positioned above the cooking enclosure and the heating unit, a fan mounted in the fan chamber to create a cooling air flow through the fan chamber, a plurality of air inlets to the fan chamber to allow the cooling air flow into the fan chamber, and a cooling manifold surrounding the opening in the upper surface and facing the upper surface outside of the cooking enclosure. The cooling manifold is in fluid communication with the fan chamber and includes a plurality of air outlets arranged to direct the cooling air flow from the fan chamber toward the upper surface of the cooking enclosure to cool the upper surface.




In accordance with another aspect of the invention, a counter-top electric oven for cooking food includes a cooking enclosure, a power head detachably connected to the cooking enclosure, and a plastic base that supports the cooking enclosure. The cooking enclosure includes an oven housing and a metallic oven pan having interior and exterior surfaces and located beneath the oven housing. The power head includes a heating unit extending into the cooking enclosure. The heating unit includes an electric heating element arranged to direct heat toward the interior surface of the oven pan. The plastic base has an interior that surrounds the oven pan with an air gap and includes one or more supports for the oven pan and one or more thermal insulators between the posts and the exterior surface of the oven pan to prevent overheating of the base by the heat directed at the interior surface of the oven pan.




According to one aspect of the invention, an electric oven for cooking food includes a base, a cooking enclosure supported by the base, and a power head detachably connected to the cooking enclosure. The cooking enclosure is defined by an oven housing and an oven pan located beneath the oven housing. The oven pan is surrounded by an interior of the base and includes a lip defining an outer periphery of the oven pan. A pair of retractable handles are mounted to the lip for movement between a first position where the handles are extended from the lip so that a user may grasp the handles to remove the pan from the base and a second position where the handles are retracted toward the lip to allow the oven housing to be positioned above the oven pan without interfering with the handles. The power head includes a heating unit extending into the cooking enclosure.




In accordance with one aspect of the invention, a counter-top electric oven includes a cooking enclosure and a power head detachably connected to the cooking enclosure. The power head includes a heating unit extending into the cooking enclosure. The heating unit includes a heating element for heating the cooking enclosure. The power head further includes a controller configured to selectively power the heating element between a minimum power and a maximum power and to limit the cooking time at maximum power to a predetermined period to prevent overheating of the cooking enclosure.




According to one aspect of the invention, an electric oven includes a cooking enclosure, and a power head connected to the cooking enclosure and including a heating unit extending into the cooking enclosure. The heating unit includes a heater housing defining a cavity, a heating element mounted in the cavity for heating the cooking enclosure, and a protective grid mounted to the heater housing between the heating element and the cooking enclosure. The protective grid includes oppositely directed legs, with each leg slidably received in a mating aperture in the heater housing to detachably mount the protective grid to the heater housing. The heating unit further includes a fastener engaged with the heater housing for movement between a first position where the fastener engages one of the legs to restrict movement of the grid relative to the heater housing, and a second position where the fastener is disengaged from one of the legs to allow removal of the grid from the heater housing.




According to one aspect of the invention, an electric oven includes a base having an upwardly extending wall surrounding an interior of the base, and an oven housing having a downwardly extending wall surrounding an interior of the oven housing, and an annular lip formed on the outer surface of the downwardly extending wall of the oven housing. The annular lip is engageable with the upwardly extending wall of the base to support the oven housing on the upwardly extending wall of the base with a portion of the downwardly extending wall extending below the lip and cooperating with the upwardly extending wall of the base to restrict the leakage of hot gases from the interiors of the base and the cooking enclosure. A relief is provided on the portion of the downwardly extending wall to ease engagement of the oven housing with the base.




Other objects and advantages will become apparent from the following specification taken in connection with the accompanying drawings.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view of a counter-top infrared electric oven embodying the features of the invention;





FIG. 2

is an exploded view of the oven shown in

FIG. 1

;





FIG. 3

is a somewhat diagrammatic section view of the oven shown in

FIG. 1

;





FIG. 3A

is an enlarged view of the area indicated by lines


3


A—


3


A in

FIG. 3

;





FIG. 4

is a perspective view of an oven pan of the oven shown in

FIG. 1

;





FIG. 5

is an exploded view of a power head of the oven shown in

FIG. 1

;





FIG. 6

is an enlarged view of the area indicated by lines


6





6


in

FIG. 3

;





FIG. 7

is a diagrammatic representation of the operating components of the oven shown in

FIG. 1

;





FIG. 8

is a flow chart illustrating selected operational features of the oven shown in

FIG. 1

;





FIGS. 9A-D

are perspective views illustrating the mounting and the removal of a protective grid of the oven shown in

FIG. 1

;





FIG. 10

is a perspective view of an optional embodiment of a base for the oven shown in

FIG. 1

;





FIG. 11

is an enlarged, fragmentary section view taken substantially along line


11





11


in

FIG. 10

;





FIG. 12

is a perspective view of another optional embodiment of a base


10


for the oven shown in

FIG. 1

; and





FIG. 13

is an enlarged, fragmentary section view taken substantially along line


13





13


in FIG.


12


.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




An exemplary embodiment of a counter-top electric oven made according to the invention is described herein and is illustrated in the drawings in connection with an infrared counter-top oven. However, it should be understood that many features of the invention may find utility in other types of counter-top electric cooking ovens, including those using cyclonic air flow in combination with simple resistance electric heating elements. Accordingly, no limitation is intended to use in connection with an infrared heating element except insofar as expressly stated in the appended claims.




With reference to

FIGS. 1 and 2

, a counter-top electric oven


10


includes a base


12


, an oven pan


14


supported by the base


12


, a cooking rack


16


supported by the oven pan


14


, a generally cylindrical, transparent oven housing


18


supported by the base


12


, and a power head


20


supported on the oven housing


18


and detachably connected to the oven housing


10


. Together, the oven pan and the oven housing


18


define a cooking enclosure


21


with the oven


10


is in the assembled state shown in FIG.


1


.




As best seen in

FIGS. 2 and 3

, the base


12


has an interior surface


22


defined by a generally cylindrical side wall


24


and a planar bottom


26


. A pair of handles


27


extend from the cylindrical side wall


24


to allow a user to move the oven from one location to another. The interior surface


22


surrounds the oven pan


14


and is spaced from the oven pan


14


by an air gap. The base


12


further includes one or more supports


28


for the oven pan


14


and one or more thermal insulators


30


between the one or more supports


28


and the oven pan


14


to prevent overheating of the base


12


by the heat from the oven pan


14


. In the preferred embodiment shown in

FIGS. 2 and 3

, the one or more supports


28


are provided in the form of three cylindrical pillars


28


A, and the one or more thermal insulating spacers


30


are provided in the form of three cylindrical spacers


30


A, each supported by one of the pillars


28


A. As seen in the section view of the spacer


30


A and pillar


28


A in

FIG. 3

, each of the spacers


30


A includes a cylindrical stub


32


that is engaged in a mating hole


36


in each pillar


28


A to retain each of the spacers


30


A to the respective pillar


28


A. While it is preferred that the cross-sections of the spacers


30


A and the pillars


28


A be generally circular, it should be understood that the invention contemplates non-circular cross-sections, such as, for example, triangular, oval, square, rectangular, trapezoidal, hexagonal, etc. The oven pan


14


is supported on the insulators


30


to maintain the air gap between the interior surface


22


and the cooking pan


14


and to prevent overheating of the base


12


, including the handles


27


. Preferably, the plastic base


12


is made from a suitable polycarbonate material and the thermal insulators


30


are made from a suitable silicone rubber insulating material.




The metallic oven pan


14


includes an interior surface and an exterior surface


38


defined by a cylindrical side wall


39


and a planar bottom


40


. Preferably the oven pan


14


is a one piece construction made of aluminum plate with a suitable nonstick PTFE coating on the interior surface


37


. A pair of retractable handles


41


are mounted to a lip


42


that defines an outer periphery of the oven pan


14


. The handles


41


are mounted to the lip


42


for movement between a first position, shown in

FIG. 2

, where the handles


41


are extended from the lip


42


so that a user may grasp the handles


41


to remove the pan


14


from the base


12


, and a second position, shown in

FIG. 4

, where the handles


41


are retracted toward lip


2


to allow the oven housing


18


to be positioned above the oven pan


14


, as shown in

FIG. 3

, without interfering with the handles


41


. As best seen in

FIG. 4

, each of the handles


41


has a pair of legs


43


extending from a grasping member


44


. Each of the legs


43


are received in a vertical guide hole


45


formed in the lip


42


to guide the handles


41


between the first and second positions. Each of the legs terminate in a tab


46


that engages the lip


42


with the handle


41


in the first position. Preferably, the handles are made from a unitary piece of metallic wire that is bent to form the grasping member, the legs


43


, and the tabs


46


.




The cooking rack


16


includes a planar grid


47


for supporting food items that are being cooked, a first set of loop projections


48


extending in one direction from the plane of the grid


47


and a second set of loop projections


49


extending in the opposite direction from the plane of the grid


47


. The projections


48


can be used to support the grid to provide a first cooking height for food items supported by the grid


47


, while the projections


49


can be used to support the grid


47


to provide a second cooking height for the grid


47


. Preferably, the cooking rack


16


is made from


304


stainless steel with a suitable non-stick PTFE coating.




As best seen in

FIG. 3

, the oven housing


18


includes an interior surface


50


defined by a generally cylindrical side wall


52


that blends into a generally conicalshaped side wall


54


which in turn blends into a planar upper wall


56


which finally blends into a generally cylindrical ring


58


. An annular lip


59


is formed on the outer surface of the wall


52


and serves to support the oven housing


18


on the side wall


24


of the base


12


. A portion


60


of the wall


52


that extends below the lip


59


cooperates with the side wall


24


of the base


12


to restrict the leakage of hot gases, such as steam, from the cooking enclosure


21


. As best seen in

FIG. 3A

, the portion


60


includes an annular lead-in chamfer or relief


61


that serves to guide the portion


60


into the base


12


, thereby easing the engagement of the oven housing


18


to the base


12


and preventing the mislocation of the housing


18


relative to the base


12


. The relief


61


allows for the portion


60


to be inserted into the base


12


without precise vertical movement of the housing


18


relative to the base


12


, i.e., the housing


18


can be inserted into the base


12


while being tilted somewhat relative to vertical. Preferably, the oven housing


18


is formed from a suitable transparent polycarbonate material.




As best seen in

FIGS. 3 and 5

, the power head


20


includes an exterior housing assembly


62


. The assembly


62


includes a domed shape upper housing


64


having a pair of handles


64


, and a lower housing


66


including a cylindrical wall portion


66


and an annular flange


70


. As seen in

FIG. 2

, four equally spaced lands


72


(only one shown) are raised from the cylindrical wall


66


to engage a plurality of ramped tabs


74


formed on the ring


58


of the housing


18


to detachably connect the power head


20


and the housing


18


. The power head


20


further includes a motor


76


for driving a cooling fan


78


and an oven fan


80


via a common shaft


82


, an infrared electric heating element


84


, a heater/fan housing


86


, a radiation plate


88


mounted to an interior surface of the heater housing


86


, a glass fiber thermal insulator


90


mounted between the heater housing


86


and the motor


76


, a mica sheet


92


mounted between the upper housing


64


and the lower housing


66


, a protective grid


94


, a thermistor


96


, a thermostat


98


, and a controller


100


including a pair of control boards


102


and


164


for controlling the heating element


84


and the motor


76


in response to signals from the thermistor


96


and command signals input into a control panel


106


by a user. Preferably, the fan


78


is made of a suitable plastic material, while the fan


80


and the radiation plate


88


are made of aluminum plate in order to reflect the infrared energy from the heater


84


down toward the interior of the cooking enclosure


19


. It is also preferred that the motor


76


drive the fans


78


and


80


at a speed in the range of 2500 rpm, which should provide an adequate air flow from the fan


80


to create a relatively even temperature throughout the cooking enclosure


21


and to speed the cooking of food by convection to supplement the infrared cooking, without generating the high speed air motion associated with some cyclonic electric counter-top ovens. Another benefit of the relatively low speed air flow created by the fan


80


is that it helps to maintain the hot surfaces of the oven


10


in a temperature range that will tend to emit infrared radiation and limits the decrease in emissivity of the non-metal materials of the oven


10


. It is preferred that the heating element


84


be made of an incoloy


840


material coated with a G-1500 (CRC 1500) ceramic coating having a coating thickness of 20±5 μm, with the main components of the coating material being SiO


2


, TiO


2


, and Al


2


O


3


, with an inorganic pigment, mainly Si—O. The ceramic coating increases the emissive power of the heating element and shifts the emission spectrum to the infrared range. With this coating, the heating element


84


is capable of generating approximately 98% or more of its heat radiation in the infrared range. A sol-gel coating method is used for coating the ceramic material firmly onto the incoloy


840


material. Infrared electric heating elements of this construction have been used in the past on hair dryers, bread makers, etc. The grid


94


is preferably made of


304


stainless steel or from any suitable PTFE coated metallic material. Preferably, the upper housing is made from a suitable polycarbonate material and the lower housing and the heater housing are made from zinc plated steel or steel coated with a suitable non-stick PTFE coating.




Together, the cylindrical wall portion


68


of the lower housing


66


, the heater housing


86


, the radiation plate


88


, the fan


80


, and the heating element


84


define a heating unit


108


that extends into the cooking enclosure


21


through an opening


110


defined by the cylindrical portion


58


of the housing


18


. Together, the upper housing


64


and the mica sheet


92


define a fan chamber


111


that is thermally insulated from the interior of the cooking enclosure


21


by the mica sheet


92


, the glass fiber insulator


90


, the heater housing


86


, the radiation plate


88


, and the lower housing


66


. As best seen in

FIGS. 3 and 5

, a plurality of cooling air outlets


112


are formed in the annular flange


70


of the lower housing


66


. Cut-outs


113


are provided in the mica sheet


92


to prevent interference between the outlets


112


and the mica sheet


92


and to allow a cooling air flow to pass through the mica sheet


92


to the outlets


112


. Preferably, the outlets


112


are equally circumferentially spaced around the flange


70


.




Together the flange


70


and the outlets


112


define a cooling manifold


114


that surrounds the opening


110


of the housing


18


and faces the surface


56


outside of the cooking enclosure


21


. The cooling fan


78


actively cools the fan chamber


111


and the walls


52


,


54


,


56


and


58


of the housing


18


by drawing a cooling air flow through a plurality of inlet openings


116


formed in the upper housing


64


and forcing the cooling air to exit through the outlets


112


, which direct the cooling air flow toward the surface


56


of the housing


18


to cool the housing


18


, as indicated by arrows A.




As best seen in

FIG. 6

, the wall


68


and the flange


70


are spaced from the cylindrical ring


58


of the housing


18


by the tabs


74


to define a hot gas vent


118


that surrounds the heating unit


108


between the heating unit


108


and the outlets


112


to vent hot gas, such as steam, from the inside of the cooking enclosure


21


for mixture with the cooling air flow from the air outlets


112


, as shown by the arrow B.




The control boards


102


and


104


are spaced from the interior surface of the upper housing


64


by a plurality of mount supports


120


to allow the cooling air flow to pass over both sides of the control boards


102


and


104


as it circulates around the fan chamber


111


before exiting through the outlets


112


, thereby enhancing the cooling of the electronics on the control boards


102


and


104


.




As best seen in

FIG. 7

, the controller


100


is connected to the motor


76


and the heating element


84


to control the flow of electric power to the motor


76


and the heating element


84


in response to signals from the thermistor


96


and command signals input by the control panel


106


by a user. The controller is configured to selectively power the heating element at a number of power levels P from a minimum power to a maximum power. At each power increment P, the controller


100


powers the heating element when the thermistor


96


indicates that the temperature in the cooking enclosure


21


has fallen below a low temperature set point associated with the particular power level P. The controller


100


then terminates power to the heating element


84


when the temperature indicated by the thermistor


96


exceeds a high temperature set point associated with the particular power level P. The controller provides power continuously to the motor


76


during the heating operations regardless of the power level selected.




As best seen in

FIG. 8

, the controller is configured to limit the cooking time at the maximum power setting to two hours to prevent overheating of the oven


10


. More specifically, after a user sets the power level P and enters the desired cook time t at block


130


, it is determined at


132


whether the power has been set to the maximum power level. If the power is set to maximum, it is determined at


134


whether the desired cooking time exceeds two hours. If the desired cooking time exceeds two hours, the cooking time is automatically limited to two hours by the controller


100


at


136


. If the desired cooking time is less than two hours, or if the power level P is not set to maximum, the controller is configured to run the heating element


84


and the motor


76


at the power level P and for the desired cooking time t, as shown at block


138


.




After the cooking time has expired, the controller


100


is configured to terminate power to the heating element


84


and to the motor


76


. However, as an optional feature, after the cooking time has expired, the controller


100


can be configured to terminate power to the heating element


84


while providing power to the motor


76


for a five minute cooling stage, as shown at


140


and


142


. This may allow time for the hot gases in the cooking enclosure


21


to vent and to be cooled by the cooling air flow from the outlets


112


, thereby preventing hot gases, such as steam from accumulating in the cooking enclosure


21


and/or the fan chamber


111


and also preventing the handles


65


from overheating.




As best seen in

FIG. 9A

, the protective grid


94


includes a first pair of legs


150


that are oppositely directed relative to a second pair of legs


152


. As best seen in

FIG. 9B

, each of the legs


150


,


152


, is slidably received in a mating aperture


154


in the heater housing


86


to detachably mount the protective grid


94


to the heater housing


86


. A fastener


156


is engaged with the heater housing


86


for movement between a first position shown in

FIG. 9A

where the fastener engages one of the legs


152


to restrict movement of the grid


94


relative to the heater housing


86


to prevent removal of the grid


94


from the heater housing


86


, and a second position shown in

FIG. 9B

where the fastener is disengaged from the one leg


152


to allow removal of the grid


94


from the heater housing


86


. Preferably, as seen in

FIG. 9B

, the fastener


156


is provided in the form of a threaded set screw that is threadably engaged with the housing


86


, with the end of the set screw frictionally engaging the one leg


152


in the first position shown in FIG.


9


A. In this regard, it should be noted that for the fastener to be in the second position it need not be completely removed from the housing


86


as shown in

FIG. 9B

, rather, the fastener


156


need only be positioned so that it is disengaged from the one leg


152


to allow movement of the grid


94


relative to the housing


86


. As best seen in

FIG. 9C

, with the fastener


156


in the second position, the legs


152


can be slid in the apertures


154


to allow the grid


94


to move relative to the housing


86


in the direction of the legs


152


, as indicated by Arrow A, to thereby remove the legs


150


from their mating apertures


154


. Once the legs


150


are removed from their mating apertures


154


, the grid


94


can be tilted downward as shown by the arrow B in FIG.


9


D and then the grid


94


can be moved in the direction of the legs


150


, as indicated by Arrow C, to thereby remove the legs


152


from their mating apertures


154


and thus, the grid


94


from the housing


86


. Removal of the grid allows for cleaning of the heating element


84


, the fan


80


, the reflector plate


88


, and the interior of the housing


86


.




As best seen in

FIGS. 10 and 11

, in an optional embodiment of the base


12


, the one or more supports


28


are provided in the form of three or more circumferentially spaced feet


28


B that extend from the side wall


24


to underlie the oven pan


14


, and the thermal insulators


30


are provided in the form of three or more thermal insulating spacers


30


B, each supported by one of the feet


28


B.




As best seen in

FIGS. 12 and 13

, in one optional embodiment of the base


12


, the one or more supports


28


is provided in the form of an annular shoulder


28


C formed on the interior surface


22


of the base


12


, and the one or more insulators


30


are provided in the form of a thermal insulating ring


30


C that is supported by the shoulder


28


C.



Claims
  • 1. An electric oven for cooking food, the oven comprising:a cooking enclosure including an upper surface with an opening therein; and a power head detachably connected to the cooking enclosure and including a heating unit extending into the cooking enclosure through said opening, a fan chamber positioned above the cooking enclosure and the heating unit, a fan mounted in the fan chamber to create a cooling air flow through the fan chamber, a plurality of air inlets to the fan chamber to allow said cooling air flow into the fan chamber, and a cooling manifold surrounding said opening and including a lower surface facing said upper surface outside of said cooking enclosure, the cooling manifold in fluid communication with the fan chamber and including a plurality of air outlets arranged in said lower surface to direct the cooling air flow from the fan chamber toward the upper surface of the cooking enclosure to cool the upper surface.
  • 2. The electric oven of claim 1 wherein said heating unit includes an electric infrared heating element made of incoloy 840 coated with a coating material, the main components of the coating material being SiO2, TiO2, and Al2O3.
  • 3. An electric oven for cooking food, the oven comprising:a cooking enclosure including an upper surface with an opening therein; and a power head detachably connected to the cooking enclosure and including a heating unit extending into the cooking enclosure through said opening, a fan chamber positioned above the cooking enclosure and the heating unit, a fan mounted in the fan chamber to create a cooling air flow through the fan chamber, a plurality of air inlets to the fan chamber to allow said cooling air flow into the fan chamber, and a cooling manifold surrounding said opening and facing said upper surface outside of said cooking enclosure, the cooling manifold in fluid communication with the fan chamber and including a plurality of air outlets arranged to direct the cooling air flow from the fan chamber toward the upper surface of the cooking enclosure to cool the upper surface. wherein said heating unit is spaced from said opening to define a hot gas vent surrounding said heating unit and located between said heating unit and said air outlets to vent hot gas from the inside of the cooking enclosure for mixture with said cooling air flow from said air outlets.
  • 4. The electric oven of claim 3 wherein said electric oven further includes a controller configured to run the fan for a predetermined cooling period after power to the heating unit has been terminated.
  • 5. An electric oven for cooking food, the oven comprising:a cooking enclosure including an oven housing and a metallic oven pan having interior and exterior surfaces and located beneath the oven housing; a power head detachably connected to the cooking enclosure and including a heating unit extending into the cooking enclosure, the heating unit including an electric heating element arranged to direct heat toward the interior surface of the oven pan; and a plastic base having an interior that surrounds the oven pan with an air gap, the base including one or more supports for the oven pan and one or more thermal insulators between the posts and the exterior surface of the oven pan to prevent overheating of the base by the heat directed at the interior surface of the oven pan.
  • 6. The electric oven of claim 5 wherein the one or more supports comprises a plurality of support posts, and the one or more thermal insulators comprises a plurality of thermal insulators, each insulator between one of the support posts and the exterior surface of the pan.
  • 7. The electric oven of claim 5 wherein the interior of the base is defined by an upwardly extending side wall, the one or more supports comprises a plurality of feet that extend from the side wall to underlie the oven pan, and the one or more thermal insulators comprises a plurality of thermal insulators, with each insulator positioned between one of the feet and the exterior surface of the oven pan.
  • 8. The electric oven of claim 5 wherein the one or more supports comprises an annular shoulder on the interior of the base, and the one or more thermal insulators comprises an annular insulating ring between the shoulder and the exterior surface of the oven pan.
  • 9. The electric oven of claim 5 wherein the base comprises a polycarbonate material.
  • 10. The electric oven of claim 5 wherein the insulators comprise a silicon material.
  • 11. The electric oven of claim 5 wherein the one or more supports are a unitary part of the base.
  • 12. An electric oven for cooking food, the oven comprising:a base; a cooking enclosure supported by the base, the cooking enclosure defined by an oven housing and an oven pan located beneath the oven housing and surrounded by an interior of said base, the oven pan including a lip defining an outer periphery of the oven pan, and a pair of retractable handles mounted to the lip for movement between a first position where the handles are extended from the lip so that a user may grasp the handles to remove the pan from the base and a second position where the handles are retracted toward the lip to allow the oven housing to be positioned above the oven pan without interfering with the handles; and a power head detachably connected to the cooking enclosure and including a heating unit extending into the cooking enclosure.
  • 13. The electric oven of claim 12 wherein each of the handles has a pair of legs extending from a grasping member, each of the legs received in a guide hole formed in the lip to guide the handles between the first and second positions, each of the legs terminating in a tab that engages the lip with the handle in the first position.
  • 14. The electric oven of claim 13 wherein each of the handles comprises a unitary piece of wire that is bent to form the grasping member, the legs, and the tabs.
  • 15. A counter-top electric oven for cooking food, the oven comprising:a cooking enclosure including an oven housing and a metallic oven pan having interior and exterior surfaces and located beneath the oven housing, the oven housing including an upper surface with an opening therein, the oven pan including a lip defining an outer periphery of the oven pan, and a pair of retractable handles mounted to the lip for movement between a first position where the handles are extended from the lip so that a user may grasp the handles to remove the pan from the base and a second position where the handles are retracted toward the lip to allow the oven housing to be positioned above the oven pan without interfering with the handles, each of the handles having a pair of legs extending from a grasping surface, each of the legs being received in a guide hole formed in the lip to guide the handles between the first and second positions, each of the legs terminating in a tab that engages the lip with the handle in the first position; a power head detachably connected to the cooking enclosure and including a heating unit extending into the cooking enclosure through said opening, the heating unit including an electric heating element arranged to direct heat toward the interior surface of the oven pan, the heating unit spaced from said opening to define a hot gas vent surrounding said heating unit to vent hot gas from the inside of the cooking enclosure, the power head further including a fan chamber positioned above the cooking enclosure and the heating unit, a fan mounted in the fan chamber to create a cooling air flow through the fan chamber, a plurality of air inlets to the fan chamber to allow said cooling air flow into the fan chamber, and a cooling manifold surrounding said opening and said hot gas vent and facing said upper surface outside of said cooking enclosure, the cooling manifold in fluid communication with the fan chamber and including a plurality of air outlets arranged to direct the cooling air flow from the fan chamber toward the upper surface of the cooking enclosure to cool the upper surface and to mix with said hot gas from said hot gas vent; and a plastic base having an interior that surrounds the oven pan with an air gap, the base including a plurality of support posts to support the oven pan and a plurality of thermal insulators between the posts and the exterior surface of the oven pan to prevent overheating of the base by the heat directed at the interior surface of the oven pan.
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