Upright radiant electric heating appliance

Information

  • Patent Grant
  • 6351602
  • Patent Number
    6,351,602
  • Date Filed
    Friday, July 14, 1995
    29 years ago
  • Date Issued
    Tuesday, February 26, 2002
    22 years ago
Abstract
An upright radiant electrical heater has a reflector assembly supporting a vertically-extending heating element assembly that radiates energy through substantially 360 degree. The reflector assembly includes heat reflective panels that disperse heat horizontally over substantially 90 degrees through an open grill at the front of the heater and vertically in a substantially uniform manner so that hot spots are avoided. A fan forces room air into the heater from below the reflector assembly, upwardly through an air passage behind the assembly into an open control chamber at the top of the heater, and outwardly into the room through ducts along the top front edge of the assembly. A thermostatic control for the heating element assembly and the fan motor is located in the air passage at the top of the heater. The flowing air maintains the exterior of the heater relatively cool to the touch, allowing parts of the housing to be molded from a thermoplastic material into aesthetically-pleasing shapes. Power is supplied to the heating element assembly by one or more cold wires including a horizontally-extending cold wire section located between the bottom of the heating element assembly and the top of the fan blade. The heating element assembly includes coiled resistance wires which are mounted in tension in order to reduce noise created by the heating element assembly when first energized.
Description




BACKGROUND OF THE INVENTION




This invention relates generally to portable electric room air heaters and particularly to upright radiant heaters suitable for placement in a corner or any other location in a room while occupying a minimum amount of floor space. As will become apparent to those familiar with the art, aspects of this invention may be used with other types of heaters.




An upright or so-called “tower” heater is relatively tall in relation to its horizontal area or “footprint.” Examples are shown in U.S. Design Pat. No. 111,000, granted Aug. 23, 1938, to C. Knox et al., and U.S. Design Pat. No. 141,834 granted to W. E. Maxson, Jr. on Jul. 10, 1945. These may be contrasted to horizontal heaters that have a relatively low profile, such as shown in U.S. Pat. No. 3,175,550, issued to R. S. Knapp on Mar. 30, 1965, U.S. Pat. No. 3,059,090, granted to R. S. Waters on Oct. 16, 1962, and U.S. Pat. No. 3,610,882, issued to William A. Omohundra on Oct. 5, 1971.




One of the problems encountered in any portable heater is the creation of localized “hot spots” on or adjacent the heater. These are areas that get much hotter than adjacent areas. Hot spots are undesirable because they can present a fire hazard as well as cause discomfort to the user of a heater. Portable electric air heaters sold in the United States at this time must meet testing requirements of Underwriter's Laboratories, Inc. when in actual service, so that the heaters do not present a risk of fire, electric shock or personal injury when operated continuously under abnormal conditions. With many heaters, such tests can only be passed successfully by the use of relatively expensive safety control devices.




SUMMARY OF THE INVENTION




An object of this invention is to provide a portable heater which is inherently designed to avoid the formation of hot spots and therefore, avoid the need for all but basic electrical safety devices.




Another object of the invention is to provide an efficient, upright radiant electric heating appliance which occupies minimal floor space, is easy to operate, and which is capable of heating a room relatively rapidly.




Another object is to provide a thermostatically-controlled room air heater with accurate on-and-off cycling to maintain or increase to desired room temperatures. Ancillary thereto is an object of minimizing, simplifying and reducing cost of the structure for controlling such a thermostat.




Another object of the invention is the provision of such a heater which has exterior housing portions which are relatively cool to the touch, thereby allowing such portions to be produced from thermoplastic molded materials that may readily be manufactured to various different shapes. This enables designers of heaters to design heaters of various aesthetically pleasing designs that may be produced at lower costs than similar heaters which have all metal housings.




An upright radiant electric heating appliance in accordance with this invention has a reflector assembly that includes radiant heat reflective side panels which lie in vertical planes that intersect one another at an included angle of between 90 and 180 degrees, a vertically-extending heating element assembly located near the rear of the reflector assembly that radiates heat energy throughout substantially 360 degrees in a horizontal direction, and a circular open grill at the front of the reflector assembly. Heat energy is directly radiated by the heating element assembly through the open grill or reflected by the reflective side panels through the open grill.




In a preferred embodiment, the heating element assembly is preferably spaced on the order of eight inches or more from the open grill and each reflective side panel is similarly spaced from the opposite side of the open grill. Accordingly, most of the heat energy reaching the open grill has traveled at least eight inches from the heating element assembly or from a reflective side panel. Because the reflective side panels lie at a mutually included angle of 90 degrees or more the reflected heat energy is dispersed across the open grill into the surrounding area. Hot spots are avoided because none of the heat energy is focused. The reflective side panels may be formed with vertical ribs for rigidity and also to create a pleasing visual effect due to the reflection from different planes of the visible light created by the heating element assembly.




Also forming part of the reflector assembly are horizontally extending, reflective top and bottom walls. Heat energy impinging on these walls and exiting from the open grill at the front of the reflector assembly is also dispersed across the open grill into the surrounding area. The horizonal top and bottom walls also avoid any focusing of the heat energy which might produce hot spots.




The reflector assembly may also include a reflective rear panel that connects the side panels and that is located behind the heating element assembly. Heat energy reflected by the rear panel is mostly reflected back to the heating element assembly or to the side panels. The reflective side panels and rear panel preferably are formed from a single piece of sheet metal, preferably tin plated steel. The reflective top and bottom walls can be separately formed from the same material.




Further in accordance with this invention, room air is drawn into the heater from below the reflector assembly and forced upwardly by a motorized fan through an air passage behind the reflector assembly and then through an open control chamber at the top of the heater before passing through ducts positioned along the top front edge of the reflector assembly. As well known, the air temperature at the floor of a room is cooler than the air above the floor and becomes increasingly warmer toward the ceiling of the room. Accordingly, air drawn into the bottom of the heater of this invention is relatively cool. This air is warmed as it rises inside the heater housing because it picks up heat from the backside of the reflective side and rear panels. A thermostatic control is positioned in the inside top portion of the heater. This location, as opposed to the bottom of the heater, is deemed better representative of the room air temperature sought to be obtained because of the warming of the relatively cool air drawn into the bottom of the heater. A thermostat located at the top of the heater tends to cycle on and off more frequently than would be the case if the thermostat were located upstream of the reflector assembly, near the bottom of the heater, but it enhances the ability of the thermostat to so control the heater as to maintain a relatively constant room temperature. In the preferred practice of this invention, baffles are provided to direct the air flow toward the thermostat. In addition, the power switch is also located at the top of the heater and control knobs for both the power switch and the thermostat extend upwardly from the top of the housing for ease of operation.




As a result of the combined effect of the cooling of the heater caused by the air flowing upwardly from the bottom of the heater and the sensitivity and responsiveness of the thermostatic control, a heater in accordance with this invention may have exterior housing parts which are relatively cool to the touch, thereby allowing selected exterior housing parts to be molded from thermoplastic materials which can readily be formed to aesthetically pleasing designs.




Yet another object of this invention is to provide an improved quartz heating element assembly for use in an electric heater and, more particularly, an improved heating element assembly which may be located above a fan blade. Such a heating element assembly in accordance with this invention comprises a pair of quartz heating elements each of which comprises a resistance heater wire inside a heat-radiating quartz tube. The tubes are closed at their ends by ceramic holders. Two cold wires or rods, one at each end of the resistance wire, are spot-welded to the resistance wire in each tube. The ends of the cold rods opposite the ends thereof welded to the resistance wire are connected, as by crimped connectors, to flexible wires that connect the heating elements into the heater control circuit. The cold wire at the bottom of each heating element extends horizontally outwardly in the space between the fan blade and the lower ceramic holder to a point sufficiently spaced in a horizontal direction from the center axis of the fan blade that the flexible wire can be safely connected thereto at that point.




Yet another object of this invention is to decrease the noise associated with the operation of quartz heaters. A quartz heating element typically produces an annoying noise each time it is energized. In accordance with this invention, the noise is substantially reduced by placing the resistance heater wire under slight tension by elongating it so that its coils are not simply stacked, in a relaxed condition, one on top of the other. The elongation is relatively quite small, on the order of ⅝ inch for a resistance heating wire having a coiled length of about 14 ¼ inches, and does not appear to separate the coils from one another. An elongation which is adequate to substantially decrease the start-up noise can be determined by trial and error, but is preferably only so much as to reduce noise. A substantial elongation, such as would cause the wire coils to be noticeably spaced from one another, would likely adversely affect the useful life of the heating element. The reasons why such a relatively small elongation decreases the start-up noise is not fully known, but may be due to the lessening of the frictional engagement between the mutually adjacent coils which are caused to vibrate relative to one another due to magnetic effects which are present during start-up. The magnetic effects would presumably disappear as soon as the resistance wire heats to a temperature exceeding its Curie temperature.




To achieve their desired elongation, the coiled resistance wires are suspended from the upper ceramic holder by means of cooperating surfaces of the upper ceramic holder and the upper cold wires and, in addition, the resistance wires are stretched by the desired amount in order to bring surfaces of the lower cold wires into engagement with downwardly facing surfaces of the lower ceramic holder.




Other objects and advantages will become apparent from the following description and the accompanying drawings.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is an exploded perspective view of the primary elements of the upright radiant electric heating appliance of this invention.





FIG. 2

is a perspective view, on a smaller scale than

FIG. 1

, of the heater of FIG.


1


.





FIG. 3

is a vertical, sectional view of the heater of

FIG. 2

taken substantially along the lines


3





3


of FIG.


2


and on a larger scale than FIG.


2


.





FIG. 4

is an enlargement of circled portion


4


at the upper right hand corner of

FIG. 3

, with parts omitted.





FIG. 5

is a fragmentary cross-sectional view looking upwardly along lines


5





5


of FIG.


3


.





FIG. 6

is a fragmentary cross-sectional view taken generally along lines


6





6


of FIG.


3


.





FIG. 7

is an enlarged, fragmentary sectional view of part of the lower, left center portion of FIG.


3


.





FIG. 8

is a fragmentary plan view taken substantially along lines


8





8


of FIG.


7


.





FIG. 9

is a fragmentary, partially exploded, perspective view of a heating element assembly forming part of the heating appliance of this invention.





FIG. 10

is an fragmentary side elevational view, with parts in cross section, of the heating element assembly of FIG.


9


.





FIG. 11

is a fragmentary, cross-sectional view, taken along lines


11





11


of

FIG. 10

, of a portion of the heating element assembly.





FIG. 12

is a cross-sectional view, also taken along line


11





11


of

FIG. 10

, of a lower ceramic holder used in the heating element assembly.





FIG. 13

is a schematic wiring diagram of the controls for the heater.











DETAILED DESCRIPTION




With reference to

FIGS. 1

,


2


and


3


, an upright, radiant electric heating appliance in accordance with this invention, and embodying the features discussed in the foregoing Summary of the Invention, is generally designated


10


and includes a radiant heating assembly consisting of a reflector assembly, generally designated


12


, and a vertically-extending heating element assembly, generally designated


14


, supported by the reflector assembly


12


.




With reference to

FIGS. 1 and 6

, reflector assembly


12


includes a one-piece, vertically-extending reflector, generally designated


15


, a horizontal, reflective bottom wall


36


, and a horizontal, reflective top wall


38


. The reflector


15


and the reflective bottom and top walls


36


and


38


define a vertical heating chamber


17


(

FIG. 3

) which, in horizontal section, is in the shape of a truncated segment of a circle that generally matches the shapes of the walls


36


and


38


. Reflector


15


has three vertically-extending, reflective panels


16


,


18


and


20


. Side panels


16


and


20


lie in respective vertical planes that intersect one another behind the rear panel


18


at an included angle of substantially 90 degrees and the rear panel


18


joins to the side panels


16


and


20


at mutually equal included angles in excess of 90 degrees. The reflector


15


and the reflective bottom and top walls


36


and


38


are preferably made from tin plated steel sheet or other suitably reflective sheet metal.




The heating element assembly


14


is located in the rear portion of the heating chamber


17


and radiates energy throughout substantially 360 degrees toward the reflective front surfaces of the vertical panels


16


,


18


and


20


and toward an arcuately-extending, open front grill


22


covering the front of the reflector assembly


12


. Heat generated by the heating element assembly


14


, therefore, radiates both directly outwardly from the heating element assembly


14


and by reflection from the panels


16


,


18


, and


20


toward the grill


22


. Panels


16


and


20


are preferably vertically ribbed for purposes of rigidity and to create a pleasing visual effect. The heating element assembly


14


is preferably at least on the order of eight inches from the front grill


22


.




Surrounding the panels


16


,


18


and


20


and mounted on a base plate assembly


24


is a rear housing panel or outer wrapper


26


. The outer wrapper


26


is spaced horizontally from the rear surfaces of the panels


16


,


18


and


20


to provide an air passage


28


which is generally V-shaped in horizontal cross section as shown in FIG.


6


.




The top of the appliance


10


is covered by a top cap


30


which supports control members described below. The appliance


10


preferably stands approximately two feet tall, enabling easy access to the control members.




A motor and fan assembly


32


is mounted in a fan chamber


34


formed between the bottom of the base plate assembly


24


and a bottom wall


36


of the reflector assembly


12


. The top cap


30


is spaced above the horizontal top wall


38


of the reflector assembly


12


to provide a control chamber


40


between the top wall


38


and the top cap


30


at the top of the appliance


10


. Fan chamber


34


, air passage


28


and control chamber


40


are all in communication so that ambient room air taken into fan chamber


34


can flow upwardly through the V-shaped air passage


28


, into the control chamber


40


and out through plural ducts


42


spaced along the front edge of the top reflector wall


38


and shown in enlarged fashion in FIG.


4


. The ducts


42


are formed by striking plate-like portions


43


upwardly from the sheet metal that forms the top wall


38


. The plate-like portions


43


function as air deflectors which extend upwardly and rearwardly in the path of the air flowing through the control chamber


40


to assist in directing the air forwardly of the appliance


10


. (For manufacturing convenience, walls


36


and


38


are both provided with ducts, but they perform no real utilitarian function in the bottom wall


36


.) As shown by solid arrows in

FIG. 3

, intake air is received through louvers


44


in a front housing panel


46


as well as through the bottom of the base plate


24


and lower rear portion of the outer wrapper


26


(See FIG.


1


). The outer periphery of the blades


48


of the motor and fan assembly


32


is closely adjacent the outer wrapper


26


so that sufficient portions of the fan blades


48


move through an area aligned with the air passage


28


to force air to flow directly upwardly through the air passage


28


, maximizing air flow at the rear corner of the appliance


10


for purposes to be described.




The top cap


30


is tapered downwardly from the rear toward the front of the appliance


10


so that the cross-sectional area of the control chamber


40


diminishes from front to rear. Accordingly, the flowing air approaches the ducts


42


with increasing speed and forms a generally horizontal sheet of air that is expelled through the ducts


42


from the front top edge of the reflector assembly


12


. Thus, air flowing through the ducts


42


will draw heat away from the internal top portion of the reflector assembly


12


where rising heat tends to accumulate. The resulting effect is that the temperatures of the entire rear surface of the reflector assembly


12


and the adjoining housing parts are reduced by the air flow created by the motor and fan assembly


32


.




As the air flows upwardly past the vertical reflector


15


, it acquires some of the heat of the reflector and increases in temperature before it impinges upon a thermostatic element


50


shown in

FIGS. 1

,


3


and


5


. The thermostat


50


can be a conventional, purchased unit that includes a bimetallic device which can be manually adjusted to a desired temperature setting by a control knob


52


mounted in a recessed portion of the top cap


30


. (The showing of the thermostat in

FIG. 1

is somewhat simplified. It preferably is of the type having an integrally combined tip-over switch that separates the thermostat contacts to deenergize the heater in the event the heater


10


is tipped over.) With reference to

FIG. 4 and 5

, the temperature sensing portion


54


of the thermostat


50


is positioned between a pair of inwardly-directed baffles or deflectors


56


that are preferably integrally formed with the top cap


30


. The deflectors


56


direct the air flowing upwardly through the air passage


28


onto the temperature sensing portion


54


of the thermostat


50


. Since the air has been warmed during its upward flow, the temperature sensing portion


54


receives air which is an approximation of the ambient air temperature at a substantial distance above the floor. The preferred location of the thermostat


50


is on the underside of the top cap


30


because it provides satisfactory control of the heater circuit when so located and further because its control knob


52


, which is preferably at a height of about two feet, is within easy reach of a standing person. This also simplifies the control of the thermostat


50


because it only needs a simple, short control shaft for connection to the knob


52


.




The preferred heating element assembly


14


of this invention is located near the center rear of the heating chamber


17


, at least about eight inches from the grill


22


, and comprises a pair of side-by-side, vertically-oriented quartz heating elements


58


which are described in greater detail below. The two quartz heating elements


58


are confined to their vertical positions by a lower ceramic insulator or holder


60


and an upper ceramic insulator or holder


61


. The holders


60


and


61


are received within elongate openings


62


and


64


, respectively, in the reflective bottom wall


36


and the reflective top wall


38


, respectively, of the reflector assembly


12


.




With reference to

FIGS. 9 through 12

, each heating element


58


comprises an elongate, coiled resistance heater wire


100


located inside a hollow heat-radiating quartz tube


102


that is closed at its ends by the ceramic holders


60


and


61


. Two cold wires or rods


104


, one at each end of the resistance wire, and which are sufficiently stiff to have a self-supporting shape, are spot-welded to the resistance wire


100


in each radiating tube


102


. (Here it may be noted that the diameters of the resistance wires


100


are shown somewhat oversized relative to the cold wires


104


in

FIGS. 9 and 10

. In actual practice, the resistance wires


100


are quite thin.) The ends of the cold wires


104


opposite the ends thereof welded to the resistance wires


100


are connected, as by crimped connectors


106


, to flexible wires


108


that connect the resistance heater wires


100


into the heater control circuit, which will be described below.




The ceramic holders


60


and


61


are preferably of identical construction. The holder


60


will now be described but it will be understood that the holder


61


has the same construction. Holder


60


is provided with a pair of radiating tube-receiving sockets


110


that receive the lower ends of the quartz radiating tubes


102


. The cold wires


104


are bent so that horizontally-extending sections


112


thereof lie in grooves


113


in the base surfaces, designated


114


, of the sockets


110


, and bent again to form vertically-extending legs


116


received in slots


118


that open to the side of the holder


60


. During assembly of the heating elements


58


, the cold wires


104


are again bent through 90 degrees to form horizontally-extending terminal portions


120


that project out of the body of the ceramic holder


60


. Terminal portions


120


are partly confined in horizontal slots


122


which open in directions facing opposite to the directions faced by the sockets


110


. The sides of the horizontal slots


122


, prevent the terminal portions


120


from accidentally rotating about vertical axes. The horizontally-extending sections of the cold wires


104


, because engaged with oppositely-facing surfaces of the holder


60


, grip the holder


60


and thereby hold the entire heating assembly


14


together.




The cold wire


104


at the bottom of each heating element


58


extends horizontally outwardly in the space between the fan blade


48


and the lower ceramic holder


60


to a point sufficiently spaced in a horizontal direction from the center axis of the fan blade


48


that a flexible wire


108


can be safely connected thereto at that point so that it will not become entangled with the fan blade


48


.




As previously mentioned, the annoying noise produced by a conventional quartz heater can be substantially reduced by applying a slight tension to the coiled resistance wires


100


. This is readily accomplished in accordance with this invention because the resistance wires


100


are suspended by the upper cold wires


104


from the upper ceramic holder


61


and held from below by the engagement between the lower cold wires


104


and the lower ceramic holder


60


. The vertical spacing between the base surfaces of the slots


122


is so selected that the resistance wire


100


is caused to be stretched in excess of its relaxed length by the desired length. The amount by which the coiled resistance wire is stretched and a possible theory as to why such stretch is useful for reducing noise are discussed above.




When the reflective walls


36


and


38


are assembled with the reflector


15


, tabs


66


(

FIG. 1

) on the reflector panels


16


,


18


and


20


extend through slots


68


in conventional fashion and are either bent over or crimped to make the walls


36


and


38


and panels


16


,


18


and


20


into a unitary structure. With the ceramic holders


60


and


61


of the heating element assembly


14


being mounted in the bottom and top wall openings


62


and


64


, respectively the heating element assembly


15


also becomes integral with the reflector assembly


12


. The front grill


22


likewise becomes integral with the reflector assembly


12


by virtue of having several longer vertical wires


70


extending through holes


72


in the top reflector wall


38


and the bottom reflector wall


36


. The longer vertical wires


70


also extend downwardly inside hollow, vertical support posts


73


forming part of the base plate assembly


24


and which assist in supporting the reflector assembly


15


above the base plate assembly


24


. As is readily apparent, the entire heater


10


comprises a unitary assembly because the base plate assembly


24


, the reflector assembly


15


and, accordingly, the parts integral with it, and the top cap


30


are all affixed by suitable fasteners to the outer wrapper


26


.




Although it is preferred that the reflective side panels


16


and


18


are primarily located in planes that intersect at substantially 90 degrees, because this relationship is believed to be the most efficient in terms of uniform heating and minimum footprint, the side panels


16


and


20


could lie in planes that intersect at included angles between substantially 90 and less than 180 degrees. Concavely curved side panels, or side panels positioned at an included angle less than 90 degrees, would be inefficient and productive of hot spots since the heat energy would necessarily be focused to some extent. By placing the heating element assembly


14


in the position shown in

FIG. 1

, the reflective surfaces of the side panels


16


and


20


distribute radiated and reflected heat substantially uniformly across the grill


22


. So too, the reflective bottom wall


36


and top wall


38


, because horizontal, evenly disperse heat energy reflected therefrom across the grill


22


without focusing the heat energy in any direction. Any other orientation, or any curvature, of the bottom wall


36


and top wall


38


would be inefficient or cause a focusing of the heat energy.




An important advantage of the appliance design is to enable use of thermoplastic materials on many of the exterior parts. Such materials can often be molded into aesthetically pleasing shapes much more readily than metal parts. The top cap


30


, the base plate


24


, the front housing panel


46


and control knob


52


can all be made of ABS plastic. An example of the advantage of using molded plastic parts is that a finger-receiving handle, designated


78


in

FIGS. 1 and 3

, can be conveniently molded into the top cap


30


.





FIG. 13

illustrates a presently preferred control circuit for the heater


10


. In addition to the thermostat


50


, the heater


14


and the motor and fan assembly


32


, the control circuit includes a three position power switch


80


for “off” and for energizing only one or else both of the heating elements


58


. The power switch


80


is conveniently controlled by a knob


52


mounted on the top cap


30


adjacent the thermostat control knob


32


(FIGS.


1


and


2


). A pilot light


84


, which is shown only in

FIG. 13

, is energized only when the heater is energized. The pilot light


84


is preferably mounted to or plugged in the top cap


30


in alignment with a transparent lens


86


shown in

FIGS. 1 and 2

. To guard against abnormal conditions which could cause the reflector assembly


12


to become dangerously hot, a conventional thermal limiter


88


is mounted on the reflective bottom wall


36


. The thermal limiter


88


creates on open circuit condition when overheated. It preferably is of the type which will automatically reset when cooled down but could be a manually resettable or else a one-shot device. A buzzer


90


is preferably provided to function as an alarm indicative of abnormal operation in the event that the thermal limiter


88


disables the heater circuit. Buzzer


90


is shown only in FIG.


13


. It can conveniently be located in the fan chamber


34


and has such a high impedance that its presence in the circuit will not interfere with the operation of the thermal limiter.




Various other advantages of the structure described herein will become apparent from a review of this disclosure, and various changes may be made without departing from the spirit and scope of the claims.



Claims
  • 1. An upright radiant electric heating appliance, comprising:a reflector assembly; a heating element assembly supported adjacent to said reflector assembly and extending along a vertical axis; and a rotatable fan disposed in a fan chamber below said reflector assembly, a lower end of said heating element assembly extending into said fan chamber, said fan having a blade assembly rotatable about an axis substantially parallel to said vertical axis, part of said blade assembly intersecting said vertical axis.
  • 2. The appliance of claim 1 further comprising an electric current-carrying wire linked to the lower end of said heating element assembly, a portion of said wire extending within said fan chamber in the vertical space between the lower end of said heating element assembly and said blade assembly.
  • 3. The appliance of claim 1 wherein said heating element assembly comprises a coiled resistance wire encased in a hollow heat-transmitting glass radiating tube.
  • 4. The appliance of claim 3 wherein said radiating tube has upper and lower ends and the resistance wire contained within the tube is stretched between the upper and lower ends thereof.
  • 5. The appliance of claim 1 wherein said reflector assembly comprises vertically-extending reflective panels bounding a heating chamber having an open front, said panels including reflective side panels angled outwardly from the rear to the front of said heating chamber at a mutually included angle of substantially less than 180 degrees but not less than 90 degrees, whereupon radiant energy from said heating element is reflected by said side panels through an angle of substantially less than 180 degrees but not less than 90 degrees.
  • 6. The appliance of claim 5 wherein said reflector assembly further comprises:a horizontal top wall bounding said heating chamber, said top wall having a front edge, a rear edge and opposed side edges, and a horizontal bottom wall bounding said heating chamber, said bottom wall having a front edge, a rear edge and opposed side edges, said front edge of said bottom wall having the same shape as the front edge of said top wall and vertically aligned therewith; and wherein said panels extend vertically between said top wall and said bottom wall.
  • 7. The appliance of claim 6 wherein the front edges of both said top wall and said bottom wall are outwardly convex, and wherein an outwardly convex grill is connected between said top wall and said bottom wall at their respective said front edges, said grill being substantially open to permit radiant energy produced by said heating element assembly and reflected by said reflective surfaces to pass therethrough without substantial obstruction.
  • 8. The appliance of claim 6 wherein said panels further comprise a rear panel between said side panels and behind said heating element assembly.
  • 9. The appliance of claim 8 wherein said heating element assembly comprises a coiled resistance wire encased in a hollow heat-transmitting glass radiating tube.
  • 10. The appliance of claim 9 wherein said radiating tube has upper and lower ends and the resistance wire contained within the tube is stretched between the upper and lower ends thereof.
  • 11. An upright radiant electric heating appliance comprising:a base plate; a support mounted on said base plate; a radiant heating assembly mounted on said support, said radiant heating assembly comprising: a reflector assembly comprising a top wall having a front edge, a rear edge and opposed side edges angled outwardly from the rear edge toward the front edge at an angle substantially less than 180 degrees, and a bottom wall having a front edge, a rear edge and opposed side edges angled outwardly from the rear edge toward the front edge at an angle substantially less than 180 degrees; a vertically-extending heating element assembly extending between said top wall and said bottom wall adjacent the rear edges of said top wall and said bottom wall and radiating energy throughout substantially 360 degrees; said reflector assembly further comprising vertical panels extending between said side edges and the rear edges of both said top wall and said bottom wall, said panels having reflective front surfaces facing generally toward said heating element assembly and rear surfaces facing away from said heating element assembly; a rear housing mounted on said base plate and extending around said rear surfaces of said vertical panels between the front vertical edges of said reflector assembly, said rear housing panel being spaced horizontally from the rear surfaces of said vertical panels to form a vertically-extending air passage behind said panels; said base plate and said bottom wall being mutually spaced to provide a fan chamber open to said air passage and to ambient air; a fan mounted in said fan chamber, said fan forcing ambient air from the area surrounding the bottom of said heating appliance upwardly through said air passage; a motor for driving said fan; a top cap supported on the upper end of said rear housing panel and overlying the top wall of said radiant heating assembly, said top cap being spaced above said top wall and forming therewith a control chamber open to said vertically-extending air passage; a heater control including a control knob and a temperature sensor mounted on said top cap; air outlet ducts extending through said top wall of said radiant heating assembly adjacent its front edge, through which air driven by said fan is expelled from said radiant heater into a room; and wherein said top cap is formed from a molded thermoplastic material which is maintained cool to the touch by air passing through said control chamber and said air outlet ducts.
  • 12. The appliance of claim 11 further comprising a lower front housing panel covering a portion of said fan chamber.
  • 13. The appliance of claim 12 wherein said lower front housing panel is apertured to admit ambient air into said fan chamber.
  • 14. The appliance of claim 11 wherein said top cap has an inverted finger-receiving handle portion molded integrally therewith.
  • 15. The appliance of claim 11 wherein said top wall of said reflector assembly is horizontal and said top cap is so formed that the depth of at least a portion of said control chamber decreases from the rear toward the front so that air flowing therethrough is accelerated as it approaches said ducts to enhance the cooling effect on said top cap.
CROSS-REFERENCE TO RELATED APPLICATION

This is continuation of application Ser. No. 07/994,416, filed Dec. 21, 1992, of David B. Chaney, Barry W. Smith, and Thomas H. Mills, now U.S. Pat. No. 5,437,001.

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Continuations (1)
Number Date Country
Parent 07/994416 Dec 1992 US
Child 08/502831 US