Abstract:
A heating device of a portable nature is disclosed. The heating device of a portable nature includes a heating element, a hinged coupled to the heating element, and an arm coupled to the hinge.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Application No. 61/364,243 filed Jul. 14, 2010, entitled “Heat Lamp,” which is incorporated herein in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to food warming systems and more particularly, to an improved, heat lamp system suitable for home-use. 
     BACKGROUND 
     When serving certain foods in a home environment, it is desirable to maintain an appropriate temperature of the food to maintain the palatability of the food and to prevent the development of unsafe biological conditions. Specifically, if certain foods are maintained at temperatures between about 40° F. and about 140° F. for several hours, consumption of that food may present a high risk of food borne illness. In certain situations, prepared foods will be set out for a number of hours in order to stage a large or complex meal or allow people to eat when they are ready. 
     A number of solutions exist for home use, but each has disadvantages. Some of these solutions are electric warming plates, electric warming drawers, and hot water baths heated by self-contained alcohol burners. In commercial environments, heat lamps are frequently used for this purpose, but commercial heat lamps are generally incompatible with a residential environment because of size, weight, lack of adjustability, non-portability and other factors. 
     SUMMARY 
     The incompatibility of heat lamp systems with certain residential environments is solved by the systems and methods disclosed here. Further, the presently disclosed system may serve additional needs, such as providing a safe and rapid system for dehydrating foods. Additional and further benefits may result by employing the presently disclosed systems. 
     Certain embodiments of the present disclosure provide a heating device of a portable nature. According to one aspect of the invention, there is provided a heating device of a portable nature comprising: a heating element; a hinge coupled to the heating element; and an arm coupled to the hinge. 
     According to still another aspect of the invention, there is provided a heating device of a portable nature comprising: an emitter of electromagnetic energy; a reflective shield at least partially surrounding the emitter; an external shade at least partially surrounding the reflective shield, the external shade having an air vent; and an air space between the reflective shield and the external shade, whereby convective air is allowed to flow around the heating device, through the air space, and through the air vent. 
     Another aspect of the invention provides a heating device of a portable nature comprising: a base; a lamp assembly including: an emitter of electromagnetic energy aimed towards a target, a reflective shield at least partially surrounding the emitter and reflecting at least a portion of the electromagnetic energy towards the target, an external shade made from a first thermally insulating material, and a chimney thermally insulated relative to the reflective shield and coupled to at least one of the emitter, the reflective shield and the external shade; and a support arm mechanically connected to the base and the lamp assembly, wherein the support arm movably supports the lamp assembly. 
     Still further aspects of the invention provide a heating device of a portable nature comprising: a base; a lamp assembly comprising: a means for generating infrared radiation, a means for reflecting infrared radiation toward an intended target, a means for safely channeling high temperature convective air flows through the lamp assembly, and a means for externally shading and insulating the lamp; and a support arm mechanically connected to the base and the lamp assembly, wherein the support arm moveably supports the lamp. 
     While the term “infrared” is used to describe the energy emitted from the heating devices of the present invention, it should be understood that different embodiments of the invention will emit a much broader electromagnetic spectrum than infrared. In particular, far-infrared, mid-infrared and near-infrared may be used. Further, while emitters of the present invention may primarily emit infrared energy, other wavelengths may also be emitted simultaneously, such as for example, ultraviolet light, visible radiation (light), terahertz radiation, and microwaves. While the term “infrared” is used to describe the energy emitted, it should be understood that this term is intended to broadly include any of the noted wavelengths as well as any combination of the noted wavelengths. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A more complete understanding of the present embodiments and advantages thereof may be acquired by referring to the following description taken in conjunction with the accompanying drawings, in which like reference numbers indicate like features, and wherein: 
         FIG. 1  illustrates a heat lamp according to certain embodiments of the present invention; 
         FIGS. 2 and 2A  illustrate a cross-sectional views of a portion of a heat lamp, according to certain embodiments of the present invention; 
         FIGS. 3   a  and  3   b  provide two views of the support arm knuckle assembly from a head-on angle and a side view angle, according to certain embodiments of the present invention: 
         FIG. 4  illustrates a side, cross-sectional view of a heat lamp, according to certain embodiments of the present invention; 
         FIG. 5  illustrates a side, cross-sectional view of a heat lamp, according to certain embodiments of the present invention; 
         FIGS. 6 and 6A  illustrate views of a heat lamp, according to certain embodiments of the present invention; 
         FIGS. 7   a  and  7   b  illustrate two slightly different views of chimney  113 , according to certain embodiments of the present invention; 
         FIG. 8  illustrates a cross-sectional view of a portion of a heat lamp, according to certain embodiments of the present invention; 
         FIGS. 9   a  and  9   b  provide two views of a heat lamp, according to certain embodiments of the present invention: and 
         FIG. 10  illustrates a cross-sectional view of a heat lamp, arm, and base according to certain embodiments of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     A more complete and thorough understanding of the present disclosure and advantages thereof may be acquired by referring to the following description taken in conjunction with the accompanying drawings, in which like reference numbers indicate like features. Preferred embodiments and their advantages over the prior art are best understood by reference to  FIGS. 1-10  below. 
       FIG. 1  illustrates a heat lamp according to certain embodiments of the present invention. Heat lamp  100  includes lamp  110 , support arm  120 , and base  130 . Heat lamp  100  produces infrared energy in a generally downward direction to warm items below the lamp. One practical application is to maintain a safe temperature of prepared food items to prevent dangerous growth of bacteria in that food. Lamp  110  generates the infrared energy in a generally downward direction while maintaining a safe exterior temperature to prevent burns to a person (during adjustment or by accidental contact) coming into contact with the lamp. Support arm  120  holds lamp  110  at a proper height (e.g., approximately 15 inches) above the countertop or items to be warmed. Support arm  120  may allow for an adjustable height. Base  130  provides stability for heat lamp  100  by providing a foothold for support arm  120 . Base  130  may provide this stability through the use of a suitably large weight or through the use of stabilizing structures. 
     Lamp  110 , or head assembly, further includes handle  111 , outer shade  112 , chimney  113 , and grille  114 . Handle  111  may be a looped structure suitable for gripping to reposition lamp  110  or to redirect the energy produced by lamp  110 . For example, two heat lamps  100  may be used together to heat a large turkey or roast wherein each heat lamp  100  is positioned above and to each side of the item. Handle  111  may be used to angle each lamp  110  towards the item. Handle  111  may be made from a thermally non-conductive material to prevent transfer of heat from the hot portions of lamp  110  to handle  111 . In some embodiments, handle  111  is mounted directly to outer shade  112 , and is therefore not subjected to significant temperatures. 
     Outer shade  112  provides a safe, low-temperature external surface for lamp  110  in order to prevent burns or damage that would result from a person or non-heat safe material coming into contact with the high temperature elements of lamp  110 . Outer shade  112  may also provide a level of impact resistance to prevent damage to the internal components of lamp  110  should heat lamp  100  tip over or fall during handling. Outer shade  112  may be made from a suitable non-conductive and sturdy material with a high melting point and sufficient rigidity to hold together the components of lamp  110 . In certain embodiments, outer shade  112  may incorporate a high-temperature plastic (e.g., polyphenylene sulfide). In certain embodiments, outer shade  112  incorporate metallic material, e.g., cold rolled steel, especially where a low output or highly efficient infrared emitter is utilized. In some embodiments outer shade  112  may be lined with a thermally insulating material. 
     Chimney  113  forms a pathway for heated air to escape, thus allowing convective airflow to cool the internal structures of lamp  110 . Chimney  113  may also provide structural support for internal components (as illustrated in  FIG. 2  and described below). Chimney  113  may be made from a suitable non-conductive and sturdy material (e.g., polyphenylene sulfide). In some embodiments, chimney  113  may be made from a conductive material, e.g., steel, with additional materials supplied to insulate outer shade  112  and to prevent direct contact from the outside by a person or flammable material. Chimney  113  may include an external grille to prevent intrusion of objects into the high temperature environment within lamp  110  while still allowing convective airflow through the chimney. Materials that are specially formulated to remain stable at higher temperatures may be used. For example, polyphenylene sulfide (PPS), known under the trade name Ryton™ may be used. 
     Grille  114  maintains a physical separation of internal, high-temperature components of lamp  110  and external elements like hands, surfaces, and food items. Grille  114  may provide protection of fragile internal components from impact with hard objects and from contact with moist foods, which could cause rapid cooling of the internal heating element. Grille  114  may be a wire mesh and may extend past the edge of outer shade  112 . Grille  114  may be constructed from a thin wire or reflective wire to reduce wasteful absorption or scattering of infrared energy produced by lamp  110 . Grille  114  may be made from a clear material similar to the lens in a halogen light fixture. Alternatively, for embodiments of the invention that use a bulb as the heating element, a grill may or may not be omitted. 
     Support arm  120  further includes upper lamp pivot  121 , elbow  122 , lower lamp pivot  123 , and arm members  124 . Support arm  120  provides separation between lamp  110  and base  130 . This separation may be fixed, binary (e.g., either stored or deployed), or variable. Support arm  120  may be interchangeable to allow for different separations. Support arm  120  may be detachable for shipment or storage. More than one support arm may be provided with base  130 , each supporting the same or different lamp  110 . 
     Upper lamp pivot  121  may be a hinge or ball joint that allows a user to adjust the angle of lamp  110  relative to the countertop or food item. Upper lamp pivot  121  may be a hinge with some freedom to rotate about the lengthwise axis of arm member  124 . Upper lamp pivot  121  may include a channel housing two or more electrical wires, which provide power to lamp  110 . This channel may be enclosed. Upper lamp pivot  121  may incorporate one or more friction elements (c.a., friction washers or pads) to allow lamp  110  to maintain a set orientation after the user makes an orientation adjustment. Upper lamp pivot may include tabs and key slots (as illustrated in  FIG. 3   a ) to limit vertical rotation of lamp  110  to about zero to 45° from vertical. 
     Elbow  122  may be a hinge or ball joint that allows a user to adjust the flex of support arm  120 , which allows extension of arm  120 . In some embodiments, elbow  122  allows for variable adjustment of the separation of lamp  110  from a surface or food item and may include friction elements to allow elbow  122  to maintain a particular separation set by a user. Elbow  122  may include a channel housing two or more electrical wires, which provide power to lamp  110 . 
     Lower lamp pivot  123  may be a hinge or ball joint that allows a user to adjust the angle of support arm  120  relative to base  130 . Lower lamp pivot  123  may be a hinge with some freedom to rotate about the lengthwise axis of arm member  124 . Lower lamp pivot  123  may include a channel housing two or more electrical wires, which provide power to lamp  110 . This channel may be enclosed. Lower lamp pivot  123  may incorporate one or more friction elements (e.g., friction washers or pads) to allow support arm  120  to maintain a set orientation after the user makes an orientation adjustment. Lower lamp pivot  123  may also incorporate locking recess  134 . Lower lamp pivot  123  may also incorporate a power disconnect switch  135  (e.g., a micro switch) that may be engaged by a tab on one portion of the pivot such that when the angle of lower lamp pivot passes a threshold (e.g., 30° from vertical), the switch disconnects power to the infrared emitter. This pivot switch prevents the heat lamp from being energized in a stowed position. 
     Arm members  124  provide support for lamp  110 . Arm members  124  may be hollow tubes (e.g., round or square) providing a channel for at least two electrical wires (a hot and a neutral), which provide power to lamp  110 . Arm members may be made from a light, stiff material like aluminum. Arm members  124  may have a fixed length or may include nested members to enable telescopic extension. 
     Base  130  may be a clamp or other attachment to a countertop or other existing surface. Base  130  may incorporate weights or heavy materials to provide stability and tip-over protection. Base  130  further includes power control  131 , over-current protector  132 , tip-over switch  133 , and locking recess  134 . Power control  131  allows a user to activate or deactivate lamp  110 . Power control  131  may be an electromechanical switch or may be a microprocessor controlled switch with a user input mechanism. Power control  131  may include input for selecting from a fixed or continuous range of output levels. In some embodiments, power control  131  is a simple on/off switch. In other embodiments, power control  131  is a multiple position switch, for example, with settings for off low output, and high output. In still other embodiments, power control  131  allows a user to set an output intensity or a target food temperature, selected from a range of intensities or temperatures. In some embodiments, power control  131  includes a timer mechanism for automatically shutting off power to lamp  110  after a specified duration of time, e.g., a specified number of hours. In some embodiments, power control  131  incorporates a proximity sensor. In certain embodiments, the proximity sensor may temporarily turn off power to lamp  110  while a user has his hands under lamp  110 , for example to serve himself some food. In certain embodiments, the proximity sensor may turn off power to lamp  110  after a predetermined amount of time has passed since a user has been in proximity to the heat lamp, e.g., the proximity sensor attempts to sense that the party is over. 
     Over-current protector  132  detects an interrupts an excessive current situation. Over-current protector  132  may be a single-use fuse, resettable fuse, or a circuit breaker. Tip-over switch  133  detects a dangerous tip-over condition (e.g., tip-over past a predetermined threshold) and disconnects power to lamp  110  to prevent a possible fire hazard. Tip-over switch may be a mercury switch, a ball contact switch, or other design. Tip-over switch may be calibrated to open when base  130  is tilted more than approximately 30°. Tip-over switch  133  may be a spring-loaded, plunger actuated switch mounted on the underside of base  130 . When base  130  is flush with a countertop, the plunger is forced into a recess, which closes the switch. When base  130  tips over or is lifted from the countertop, the plunger will extend, thus opening the switch. 
     Temperature may also be controlled through the use of a remote temperature monitor that is placed proximate the food or target so as to more accurately monitor the temperature of the food or target. A temperature control may then be set to turn on and/or control the intensity of the infrared emitter when the remote temperature monitor senses a temperature below a threshold that may be set by the operator. The remote temperature monitor may comprise a probe or any other device known for this purpose. 
     Locking recess  134  provides a channel for accepting and retaining arm member  124 , e.g., for storage or shipment. Locking recess  134  may incorporate a spring-loaded locking mechanism to retain arm member  124 . In some embodiments, a retaining strap is provided to hold arm member  124  securely in locking recess  134 . In some embodiments, a power disconnect switch is incorporated into locking recess  134  to automatically disconnect power when the heat lamp is stowed. 
       FIG. 2  illustrates a cross-sectional view of a portion of a heat lamp, according to certain embodiments of the present invention. Lamp  110  includes handle  111 , outer shade  112 , chimney  113 , grille  114 , upper lamp pivot  121 , infrared emitter  201 , first reflector  202 , second reflector  203 , outer air gap  204 , vents  205 , inner air gap  206 , wire channel  210 , barrel nut  211 , wire channel  212 , thermal cut-off switch  213 , and infrared radiation path  214 . 
     Infrared emitter  201  converts electrical energy to infrared radiation. In some embodiments, infrared emitter  201  is designed to generate far infrared radiation with wavelengths in the range of about 2.7 to about 5.92 micrometers as target foods absorb radiation at these wavelengths. In some embodiments, infrared emitter  201  is an iron-chrome-aluminum heating element wrapped in ceramic fiber insulation. In some embodiments, infrared emitter  201  is composed of an open ceramic insulator supporting a nichrome coil. In some embodiments, infrared emitter  201  may be a quartz tube. In still other embodiments, infrared emitter  201  may be an infrared light bulb. Infrared emitter  201  may be round, square, rectangular, cylindrical, or any other shape. Infrared emitter  201  may be replaceable or permanently installed into lamp  110 . Infrared emitter  201  provides a means for generating infrared radiation that can be used to heat an intended target, e.g., prepared food. 
     In some embodiments, infrared emitter  201  features a ceramic heating element that generates infrared (electromagnetic radiant infrared energy) to transfer heat energy via invisible electromagnetic energy waves. Using the ceramic heating element to provide the heat may be advantageous because it delivers an even, gentle heat and zone control (i.e., the ceramic element generates infrared energy that is absorbed solely at the area it is directed). Furthermore, electric infrared may produce virtually instant heat, without the need to wait for heat buildup. Infrared heating, is not generally dependent upon air movement like convection heat. Additionally, the ceramic heating element that provides electric infrared heat may be one of the cleanest methods of heating. There are no by-products of combustion and the heating element adds nothing to nor takes anything from the air. In this way, a ceramic heating element helps maintain the flavors of the foods the heat lamp is warming. The infrared emitter may be a custom-built part or a light bulb. The custom part may be a coil of resistance wire (such as is commonly used in a toaster or a space heater) that glows red when energized. The resistance wire may emit electromagnetic energy across a broad spectrum with the predominant energy being infrared. 
     In some embodiments, some infrared radiation from infrared emitter  201  is directed generally upward or sideways toward outer shade  112  rather than generally downward toward the food. This misdirected energy would be wasted if allowed to continue in that direction and could contribute to a dangerous heating of outer shade  112  and handle  111 . First reflector  202  reflects at least some of this misdirected infrared radiation generally downward toward the food to be heated. In some embodiments, outer air gap  204  exists between outer shade  112  and first reflector  202  to allow convective air flow out vents  205 , which cools outer shade  112  and first reflector  202  and prevents conductive heating of outer shade  112  via hot stagnant air trapped between outer shade  112  and first reflector  202 . In some embodiments, outer air gap  204  is filled, at least in part, with an insulating material. In some embodiments, outer shade  112  and first reflector  202  are connected in an airtight manner (thus forming a double-walled chamber) with a substantial amount of the air in air gap  204  evacuated to form a vacuum insulator. 
     In some embodiments, first reflector  202  is a generally reflective, generally continuous, metal shield (e.g., thin rolled steel or aluminum) wrapped around the sides and much of the top of infrared emitter  201  leaving air gap  206  between first reflector  202  and infrared emitter  201 . In some embodiments, first reflector  202  may include a series of louvers at or near the top of first reflector  202 . The louvers may reflect infrared radiation downward at an angle. The louvers may allow convective air flow to pass through. In some embodiments, the louvers are arranged radially. In some embodiments, first reflector  202  may be formed from a heat-safe material (e.g., an engineering plastic) coated with a reflective foil or paint. Air gap  206  allows convective air flow around infrared emitter and out chimney  113  to prevent conductive heating of first reflector  202  via hot stagnant air trapped between first reflector  202  and infrared emitter  201 . 
     In some embodiments, second reflector  203  is provided to prevent leakage of infrared radiation through inner air gap  206  and out chimney  113 . Second reflector  203  may be positioned to reflect radiant energy downward while still maintaining inner air gap  206  and allowing, convective air flow through inner air gap  206  and out chimney  113 . For example, infrared radiation may follow path  214  upward from infrared emitter  201  before being reflected by second reflector  203  and then first reflector  202 . In some embodiments, second reflector  203  is a generally reflective, generally continuous, metal shield (e.g., thin rolled steel or aluminum) wrapped around the top of infrared emitter  201 . In some embodiments, second reflector  203  may be formed from a heat-safe material (e.g., an engineering plastic) coated with a reflective foil or paint. In some embodiments, second reflector  203  is formed from a series of louvers. The louvers may reflect infrared radiation downward at an angle. The louvers may allow convective air flow to pass through. In some embodiments, the louvers are arranged radially. The combination of one or more reflectors provides a means for reflecting infrared radiation toward an intended target that increases the efficiency of the heat lamp and reduces heating of the outer shade and handle. In certain embodiments, second reflector  203  may rotate to aid in ventilation of the high temperature components. 
     In some embodiments, the only mechanical coupling between outer shade  112  and the high temperature components (e.g., infrared emitter  201  and reflective shades  202  and  203 ) is chimney  113 . As illustrated in  FIG. 2 , no direct contact exists between the high temperature components and outer shade  112 , thereby preventing conduction of heat to outer shade  112 . However, because chimney  113  does have direct contact with the high temperature components, it should be constructed from a material that remains solid, inflammable, and structurally sound at temperatures generated by the high temperature components—e.g., infrared emitter  201  and reflectors  202  and  203 —after prolonged operation of heat lamp  100 . 
     Vents  205  allow heated air to escape out the top of lamp  110 . In some embodiments, a single vent  205  may accommodate chimney  113  to allow heated air to escape only through chimney  113 , as shown in  FIG. 2A . In some embodiments, one or more vents  205  may allow heated air to escape out the top of lamp  110  without traveling through chimney  113 , e.g., directly through air gap  204  and through vents  205 . In some embodiments, one or more vents  205  may allow ambient air to be pulled from air space  204  to mix with heated air moving through chimney  113 , thereby reducing its temperature. 
       FIG. 2  also illustrates various electrical features, according to certain embodiments of the present invention. Wire channel  210  may accommodate two or more wires, which may connect components of lamp  110  to components of base  130 . Wire channel  210  may be completely or partially enclosed. In some embodiments, wires housed in wire channel  210  will flow over keyed barrel nut  211 , which allows limited rotation of upper elbow  121 , but prevents crimping of the wire. Wire channel  210  may continue through grommet  212  to bring wires in contact with infrared emitter  201  and thermal-cutoff  213 . 
     Thermal-cutoff  213  causes an automatic disconnect of power to infrared emitter  201  in the event of an over-temperature condition. Thermal-cutoff  213  may protect internal components from dangerous temperatures in order to prevent or diffuse a fire hazard. Under normal operating conditions, convective airflow passes through air gaps  204  and/or  206 , cooling the internal components and maintaining safe operating conditions. In one abnormal circumstance, where vents  205  and chimney  113  become blocked, operation of infrared emitter  201  may cause dangerous temperatures to form within lamp  110  as no convective airflow would be possible. In another abnormal circumstance, if the open end of lamp  110  (i.e., the end with grille  114 ) were to come in contact with a surface, especially a soft surface, that contact could restrict or block convective airflow. A significant restriction or blockage of airflow through air gaps  204  and/or  206  could result in a dangerously high internal temperature, possibly causing fire, structural damage, and/or breakdown of electrical insulators. Because of the arrangement of air gaps  204  and  206 , heat lamp  100  can indirectly “sense” the airflow restriction and shut down the infrared emitter before a dangerous condition occurs. In some embodiments, thermal cutoff  213  may be thermally insulated from outer shade  213  to react to the air temperature in air gap  204 . In some embodiments, thermal-cutoff  213  may be thermally connected to outer shade  213  to react to the shade temperature. 
     Thermal-cutoff  213  may be a single use or resettable thermal-cutoff device. In some embodiments, thermal-cutoff  213  utilizes a thermal pellet, e.g., made of wax, that normally compresses a spring, holding an electrical switch closed. Once the temperature exceeds a predetermined threshold temperature, the wax melts, thereby releasing the spring and opening the switch. In some embodiments, thermal-cutoff  213  utilizes a bimetal thermal protector, which may allow for automatic self-reset once the temperature has decreased. In some embodiments, thermal-cutoff  213  may be implemented using a temperature sensor (e.g., a thermocouple) combined with a controller and a controllable switch. In certain embodiments, multiple thermal-cutoff devices may be utilized. In some embodiments, a mechanically operated thermal-cutoff to provide a high threshold fail-safe may be combined with a lower threshold control circuit. In some embodiments, two mechanically operated thermal-cutoff devices may be wired in series, one being automatically resettable with a lower threshold and one being a single-shot device with a higher threshold. Thermal cut-off  213  provides a means for preventing or interrupting a thermal overload condition. In some embodiments, the threshold temperature for thermal cut-off  213  may be set to a temperature at which a user may be burned by escaping gases or by brief contact with the outer shade. In some embodiments, the threshold temperature for thermal cut-off  213  may be set to a fraction of the melting or plastic point of chimney  113  to prevent melting or deformation of the same, even if the remaining heat energy continues to heat chimney  113  after emitter  201  has been turned off. 
       FIGS. 3   a  and  3   b  provide two views of the support arm knuckle assembly from a head-on angle and a side view angle, according to certain embodiments of the present invention.  FIG. 3   a  illustrates a cut-away, head-on view of knuckle assembly  300 . Knuckle assembly  300  allows the support arm to bend within a predetermined range of motion, e.g. from about a 10° spread (e.g., a storage position) to about a 130° spread. In some embodiments, a maximum spread of about 180° may be allowable. Knuckle assembly  300  may allow for discrete opening settings or continuous adjustment, within the predetermined range of motion. Knuckle assembly  300  includes outer housing  301 , barrel nut  302  (with tabs  303 ), screw  304 , housing key slots  305 , and friction washers  306 . 
     Outer housing  301  may be constructed in two interconnecting pieces, one connecting to upper arm member  124  and the other connecting to lower arm member. Joining those two pieces is barrel nut  302  and screw  304 , together providing compressive force on the two interconnecting pieces. Barrel nut  302  includes tabs  303  that fit into housing key slots  305  to allow a limited range of motion of knuckle assembly  300 . Friction washers  306  prevent unintended movement of knuckle  300  by countering the gravitational force generated by lamp  110 . Instead of friction washers  306 , additional tabs and slots may be provided in barrel nut  302  and outer housing  301  to allow for discrete extension positions. In some embodiments, the user would loosen screw  304  to adjust knuckle assembly  300 . In other embodiments, a spring may be provided to allow the additional tabs to move to the next slot by compressing the spring. In other embodiments of the invention, stops may be mounted in the knuckle housing to prevent the knuckle assembly  300  from rotating past 180 degrees. 
       FIG. 3   b  illustrates a cut-away side view of knuckle assembly  300  illustrating cable pathway  310 . Cable pathway  310  may be completely or partially enclosed and may wrap around barrel nut  302 . Because barrel nut  302  may be keyed into outer housing  301  (as described above), wires in cable pathway  310  are protected from shearing or crimping forces that would otherwise be applied if knuckle assembly  300  were extended past about 180°. 
     In some embodiments, the features of knuckle assembly  300  are incorporated into upper lamp pivot  121  (and lower lamp pivot  123 ). In these embodiments, the range of extension of upper lamp pivot  121  may be limited to always maintain a slight cant to lamp  110 , even when stowed. In this way, airflow is never completely restricted through lamp  110 , allowing efficient cooling even after the lamp is turned off and stowed. In some embodiments, a fan is incorporated into base  130  forcing air through a channel in support arm  120  and into lamp  110  to assist in cooling lamp  110 . In alternative embodiments, the convective flow is reversed and a fan is located in the lamp  100  to direct air downward toward the target. Placement of the fan in the base may allow for a larger, more powerful fan and it would not be as likely to overheat because it would not be proximate the infrared emitter. A fan in the base may either push or pull the air through the armature. 
       FIG. 4  illustrates a side, cross-sectional view of a heat lamp, according to certain embodiments of the present invention. Oblong lamp  400  includes infrared emitter  401 , first heat shield  402 , second heat shield  403 , air gap  404 , vents  405 , and screen  414 . Upper lamp pivot  121  may be attached to a short side or a long side of oblong lamp  400 . In some embodiments, oblong lamp  400  may include multiple infrared emitters  401 . In certain embodiments, oblong lamp  400  may include an oblong infrared emitter  401 . In some embodiments, additional chimneys  113  may be provided, e.g., at each vent  405 . 
       FIG. 5  illustrates a side, cross-sectional view of a heat lamp, according to certain embodiments of the present invention. Lamp  500  includes infrared bulb  501 , bulb positioning fins  502 , and air gap  504 . Infrared bulb  501  may be a glass bulb with a filament. Infrared bulb  501  may emit visible light as well as infrared light. Bulb partitioning fins  502  may maintain a generally uniform air gap  504  around infrared bulb  501  by physically contacting infrared bulb  501  in at least one place. Bulb partitioning fins  502  may also extend beyond shade  112  and/or infrared bulb  501  to provide impact protection. Because bulb partitioning fins  502  may create very tight tolerances, the bulb socket may need to be flexibly mounted to allow for some motion while a bulb is inserted or extracted. In certain embodiments, shade  112  of lamp  500  may be made from cold rolled steel. In certain embodiments, shade  112  of lamp  500  may be made from plastic (e.g., glass filled nylon 6). 
       FIG. 6  illustrates a view of a heat lamp, according to certain embodiments of the present invention. Heat lamp  600  includes lamp  110 , base  601 , arm members  602 , arm elbow  603 , and foundation  610 . In certain embodiments, arm elbow  603  maintains a fixed angle between arm members  602 . In certain embodiments, arm elbow  603  is made from two generally triangular pieces attached together to form two generally perpendicular channels for receiving arm members  602 . In some embodiments of the invention, the height of the lamp  110  relative to the base  610  may be adjustable. 
     Base  601  houses certain components of heat lamp  600  and provides a structural connection to foundation  610 . Base  601  provides a channel for receiving arm member  602  and connects to foundation  610  to provide indirect lateral support for lamp  110 . Base  601  includes a channel for receiving power cord  604 , convenience outlet  605 , circuit breaker  606 , and tip-over switch  607 . Convenience outlet  605  allows a user to connect a second heat lamp  600  to form a series of daisy-chained lamps, e.g., in a buffet line. In some embodiments, circuit breaker  606  provides over-current protection for heat lamp  600  by disconnecting lamp  110  in the event that current through the wires to lamp  110  exceeds a predetermined level. In some embodiments, circuit breaker  606  disconnects power to lamp  110  and convenience outlet  605  in the event that current received through power cord  604  exceeds a predetermined level. 
     Foundation  610  provides a stable platform for heat lamp  600  and a convenient interface for user interaction and control. In some embodiments, foundation  610  may be a thin base generally as large as the infrared output pattern produced by lamp  110 . In some embodiments, foundation  610  may be larger than the infrared output pattern to protect the surface below lamp  110 . In certain embodiments, foundation  610  may be thermally insulated and/or opaque to protect an underlying countertop or furniture surface from the high food temperature and/or infrared radiation. Silicone pads may also be used on the bottom of the foundation to protect a countertop. In certain embodiments, foundation  610  may be reflective to protect the countertop or furniture surface without absorbing heat, which would increase the temperature of foundation  610 . To protect the countertop or furniture surface, foundation  610  may need to be as broad as the primary heating area under lamp  110 , for example at least 16 inches in each horizontal dimension if a circular infrared emitter is 15 inches above foundation  610 . In some embodiments, foundation  610  is large enough to accommodate a standard 9″ by 13″ casserole dish. 
     The foundation  610  may also comprise a storage compartment for a variety of accessories including, for example, spare or replacement infrared radiation bulbs, serving utensils, etc. One aspect of the invention comprises serving utensils that remain cool to the touch in the presence of infrared energy. Serving utensils may be made of silicone or any material that that does not absorb infrared energy or that does not become hot in the presence of infrared energy. 
     According to alternative embodiments of the invention, the foundation  610  comprises a hot plate so as to heat the target both from the infrared radiation above and the hot plate below. Any hot plate structures known in the art may be incorporated and used in the foundation. In one embodiment, the foundation  610  may comprise a heater element that may be an etched foil design element comprising circuitry for a Kapton™/Polyimide heater. The heater element may be constructed of a material that is a polyimide polymer, for example, a Kapton™ material. Note that Kapton™ is a trademark of the DuPont™ Corporation. A Kapton™ material, in film form, can provide enhanced dielectric strength in very thin cross sections and very good bonding and heat transfer capabilities. Use may be made of a Kapton™ film having a thermal conductivity below 0.5 W/mK and a dielectric strength exceeding 1250 V, which can be achieved with a thickness between 0 and 100 μm. The heater can therefore be implemented as a Kapton™ type heater. Note that resistive heater element may be implemented as a Kapton™ type heater or a heater formed of a polyimide polymer, depending upon design considerations. 
     Kapton™/Polyimide heaters made with this DuPont™ thin film may be transparent, lightweight, flexible and are electrically strong. Kapton™/Polyimide may be compatible with foil element alloys such as inconel, nickel, copper, and stainless steel. They may have low outgassing properties, may be resistant to solvents. They may work well with adhesive systems that permit higher operating temperatures. Thermal control and sensing devices may be incorporated into the hotplate. 
     The hotplate may comprise a thin outer layer of Kapton™ (first insulating film) and a thicker layer of Kapton™ (second insulating film) between which two layers there is a layer of electrically conductive material (heater element). The layer of electrically conductive material could be formed by vacuum depositing a layer of conductive material onto the second insulating layer and then bonding the first insulating film to the layer by way of layers of adhesive material. Adhesive layers may be painted onto the insulating film layers. 
     Heater element may be a deposited ink on a dielectric that is bonded to a metal substrate. Once energized, the conductive inks may provide the heat source to elevate the soleplate temperature. The ink pattern may be two side-by-side undulating ink deposit strands similar to the strands. The ink strands may connect to form one continuous electrically resistant heat generating ink coil that is bonded to a metal substrate. 
     Foundation  610  may include control panel  611  (illustrated in  FIG. 6A ). Control panel  611  may include temperature sensor  612 , set point indicator  613 , current temperature indicator  614 , set point adjustment interface  615 , and error indicator  616 . Temperature sensor  612  provides feedback for adjusting the output of lamp  110 . In some embodiments, temperature sensor  612  may be positioned and designed to sense the temperature of food placed under lamp  110 . In some embodiments, temperature sensor  612  may attempt to sense the likely heating level of lamp  110 . For example, temperature sensor  612  may incorporate material with absorption characteristics similar to food and may be positioned within the infrared radiation pattern. In some embodiments, the value read from temperature sensor  612  may be used to automatically control the output of lamp  110 . In some embodiments, temperature sensor  612  may be remote from, e.g., a probe that may be placed on or in the food to be heated. 
     Set point indicator  613  indicates the desired output or target temperature for lamp  110 . In some embodiments, set point indicator  613  provides a display of a temperature value. In some embodiments, set point indicator provides a discrete output level indicator (e.g., high/low or a range of multiple discrete output levels). 
     Current temperature indicator  614  indicates the current temperature as measured by temperature sensor  612 . In some embodiments, current temperature indicator  614  displays the current temperature as a numeric value. In some embodiments, current temperature indicator  614  displays the current temperature as a value on a range, e.g., a bar graph indicator. In some embodiments a color scheme may indicate a danger zone temperature as a red background or with a red light. 
     Set point adjustment interface  615  allows a user to adjust the set point. In some embodiments, set point adjustment interface  615  is a switch or knob. In some embodiments, set point adjustment interface  615  is a pair of buttons or touch sensors, one for increasing the set point and one for decreasing the set point. 
     Error indicator  616  provides a display of recognized error conditions. In some embodiments, error indicator  616  warns a user of a high temperature condition in lamp  110 , which has required or may soon require an automatic shutoff of lamp  110 . In some embodiments, error indicator  616  warns a user of an unsafe food temperature condition, e.g., one signaled by a low reading at temperature sensor  612 . 
     Fan  620  provides active airflow adjustment. In some embodiments, fan  620  provides an active assist to the natural convective airflow by drawing additional cool air through lamp  110  and out the vents and/or chimney at the top of lamp  110 . In some embodiments, fan  620  may blow air downward to overpower the natural convective airflow and force the heated air downward toward the food item. Fan  620  may be manually controlled or automatically controlled. Fan  620  may have multiple speeds to adjust for varied ambient temperature conditions or internal conditions. Fan  620  may be triggered by an over-temperature condition within lamp  110 . The fan  620  may operate in any of three modes. First, the fan  620  may pull air past the heating element in the same direction as convention. Second, the fan  620  may push air down past the heating element in a direction opposite the direction of convection. Third, the fan  620  may direct air flow in a cross-wise direction relative to the direction of convection. For any of the modes of operation, the fan  620  may be located either upstream or down stream relative to the heating element and the direction of convection. Alternatively, the fan  620  may be positioned on the side of the outer shade so as to pressurize an enclosed space such that the outlet of that pressurization directs air either up (to reinforce convection) or down to improve heat delivered to the target. 
       FIG. 8  shows a cross-sectional side view of a lamp embodiment of the present invention. As previously described, the lamp  110  comprises a handle  111  connected to an outer shade  112 . An infrared emitter  201  is positioned inside the outer shade  112  and a chimney  113  extends within the outer shade  112  above the infrared emitter  201 . An upper lamp pivot  121  is also connected to the outer shade  112 . A fan  620  is positioned within the chimney  113 . In some embodiments, fan  620  may be mounted on shade  112  away from chimney  113  to provide additional air flow without being subject to the high temperature of the chimney. 
       FIG. 10  shows a cross-sectional side view of a lamp embodiment of the present invention. As previously described,  FIG. 10  illustrates a heat lamp according to certain embodiments of the present invention wherein the heat lamp  100  includes lamp  110 , support arm  120 , and base  130 . Each of the arm members  124  of the support arm  120  has a wire channel  210  within. Further, the elbow  122  and the upper lamp pivot  121  have internal conduits that allow air to flow. These components connect to form and internal conduit from the base  130  to the lamp  110 . The base further comprises a fan  620  for moving air through the internal conduit. As previously discussed, the fan may pull the air down from the lamp toward the base, or push the air from the base to the lamp. Further, while the lamp is illustrated in  FIG. 10  to have a configuration that would push air up the chimney, it may also be configured to push air out the bottom the lamp or push in both directions. 
       FIGS. 7   a  and  7   b  illustrate two slightly different views of chimney  113 , according to certain embodiments of the present invention. Chimney  113  includes chimney grille  701 , high-temperature mount points  702 , outer shade interface  703 , and side air port  704 . In some embodiments, chimney  113  may be a one-piece, molded part made from an engineered plastic or other suitable material. In some embodiments, chimney  113  may be an assembly of multiple parts and materials with different thermal and structural characteristics. 
     Chimney grille  701  provides an external exhaust port for convective air flow while preventing insertion of foreign objects or other direct contact between internal, high-temperature components and people, pets, or things. High-temperature mount points  702  provide a direct interface between high-temperature elements (e.g., one or more of first heat shield  202 , second heat shield  203 , and infrared emitter  201 ). This direct interface allows chimney  113  to physically support and stabilize the high-temperature elements. Outer shade interface  703  provides a direct interface between chimney  113  and outer shade  112 . Outer shade interface  703  allows outer shade  112  (and indirectly support arm  120 ) to support chimney  113  and, indirectly, the high-temperature components. In some embodiments, outer shade interface  703  extends from chimney  113  to maintain air gap  204 . 
     Side air port  704  may allow air flow through air gap  204  into chimney  113  (see  FIG. 2 ) to cool chimney  113  and lower the convective air temperature above lamp  110 . Further, in the event that chimney grille  701  is obstructed, hot air may flow out of side air port  704  into air gap  204 . This hot air flow may trip thermal-cutoff  213  (which may be mounted to mount points  705 ) and shut down the operation of lamp  110 . In the event that lamp  110  is tilted too shallowly (approaching horizontal), convective air flow may be disrupted causing dangerous heating of external features. In this shallow orientation, convective air flow may begin to flow out side air port  704  rather than chimney  113 , thus causing thermal-cutoff  213  (mounted at points  705 ) to trip. Chimney  113  provides a means for safely channeling high temperature convective air flows through the heat lamp. 
       FIG. 8  illustrates a cross-sectional view of a portion of a heat lamp, according to certain embodiments of the present invention. In some embodiments, lamp  110  includes a sandwich of outer shade  112  and first heat shield  202  that creates void  801 . In some embodiments, void  801  is an insulating vacuum. In some embodiments, void  801  is filled with an insulating material such as ceramic, stranded fiberglass, high temperature foam, or silicone. In certain embodiments, side air port  704  allows convective air flow along infrared emitter  201  and through chimney  113 . In certain embodiments outer shade  112  is formed, at least in part, of a thermally conductive material. 
     In certain embodiments, thermal-cutoff  213  may be mounted in thermal contact with outer shade  112  and configured with an appropriate threshold to maintain a safe temperature for that exposed surface. For example, a threshold may be set well below a temperature that might cause a contact burn in that outer shade  112  may continue to get hotter even after power is disconnected from infrared emitter  201 . In some embodiments, thermal-cutoff  713  is mounted within chimney  113  in order to react to restricted or inadequate convective air flow through chimney  113 . 
     The heater element may be an infrared source of the type that is energized very quickly. The heater element may comprise infrared quartz tubes. Any number of tubes may be positioned in any pattern. Further, the tubes may take any shape, for example, linear, arcuate, angled, figure C, figure S, square, circular, etc. Quartz tubes have electrical leads for electrically communicating with temperature control knob and electric cord. Tube clips may be mounted to the first heat shield for engagement with quartz tubes. Tube clips may suspend quartz tubes over a reflective material so as to disperse energy more evenly. The interior surfaces of the first heat shield may be coated with an infrared reflective coating to reflect energy emitted by quartz tubes toward the target. Examples of reflective coatings or materials include: gold, anodized aluminum or any other high temperature, low emissivity material. Other components may be coated with an infrared absorptive coating. Examples of absorptive coatings or materials include: ceramic, porcelain or any other high emissivity material. 
     The infrared source may be a tungsten type lamp. The infrared source may be used to quickly heat up the target. Quartz lamps may also be used. Quartz tubes may have a Watt density between about 65-120 Watts/linear inch. Quartz tubes may also have an internal gold reflector. Quartz tubes and quartz lamps may have the ability to reach maximum temperature very quickly, if not instantly. Further, quartz tubes and quartz lamps may reach maximum operating temperatures of 870° C. to 1370° C. 
     In some embodiments, head assembly  110  includes fan  620  for providing powered air flow through chimney  113 . Fan  620  may pull heated air through chimney  113  or may push ambient air through chimney  113  towards emitter  201 . In some embodiments, fan  620  may be mounted to outer shade  112 , and outside of the flow of heated air. 
       FIGS. 9   a  and  9   b  provide two views of a heat lamp, according to certain embodiments of the present invention. Heat lamp  100  includes lamp  110  may be connected in a fixed relationship with support arm  120 , which may be connected in a fixed relationship with base  130 . Support arm  120  may include a pivot and a counterbalance. Heat lamp  100  is illustrated in an operating (or open) position and a storage (or closed) position as well as in a transition between the two positions. 
       FIG. 10  illustrates a cross-sectional view of a heat lamp, arm, and base according to certain embodiments of the present invention. In certain embodiments, fan  620  pulls ambient air into base  130  and forces that air up voids  210  within arms  124 . This airflow may be controllably used to assist or resist the convective airflow through head assembly  110 . 
     While embodiments of this disclosure have been depicted, described, and are defined by reference to example embodiments of the disclosure, such references do not imply a limitation on the disclosure, and no such limitation is to be inferred. The subject matter disclosed is capable of considerable modification, alteration, and equivalents in form and function, as will occur to those ordinarily skilled in the pertinent art and having the benefit of this disclosure. The depicted and described embodiments of this disclosure are examples only, and are not exhaustive of the scope of the disclosure.