The present invention relates to portable radiant heaters and more particularly to an electrically powered radiant heater incorporating a blower for forcing air across a profile reflector surface and out into a space. The air absorbs heat from the heating elements and surfaces of the reflector, and is discharged forward from the heater, thereby augmenting radiant heating. The reflector is shaped to direct the radiant heat outwardly from the front of the heater.
Supplementary heat for limited spaces may be provided by portable heaters. Typically electrical, portable heaters may distribute heat by convection, forced air, radiation, or a combination of these, Radiant heaters have become popular since they are capable of heating solid objects within reach of the radiant heat, but they do not heat ambient air surrounding these objects. Thus, a person in the room or space benefits from the heat, although the air temperature is not greatly increased.
However, only surfaces exposed to the source of radiant heat experience heating. If, for example, a person standing by a radiant heat source turns, or if another person or object is interposed between the standing person and the heat source, the warmed part of the standing person will chill. To even the heating effect, it becomes desirable to both project radiant heat and to warm the air of the space or room.
To provide this benefit, combination radiant and forced air heaters have been proposed in the prior art. U.S. Pat. No, 5,381,509, issued to Thomas H. Mills on Jan. 10, 1995, describes such a combination of forced air and radiant heater. The heater has a reflector plate for projecting radiated heat forwardly out from the heater, and a fan located behind the reflector plate for forcing air upwardly and out from the heater.
U.S. Pat. No. 3,229,070, issued to Orville C. Wells on Jan. 11, 1966, incorporated herein by reference describes a portable forced air and radiant electric heater which illustrates typical features such as manual on-off switch, thermostatic switch for protection against overheating, heating element guard for preventing direct contact by an external object, and fins for directing airflow. The fan draws air down through the center and directs it out the sides over the circular heating rod. The Wells invention acts primarily as a conventional conductive heater where air is the conductive medium.
An industrial convection and radiant heater is shown in U.S. Pat. No. 4,336,442, issued to Eugene W. Starr on Jun. 22, 1982. Due to its industrial application, the direction of radiation and egress of heated air differs from those of the present invention. Because it is handling pressurized heated gas,
U.S. Pat. No. 1,900,956, issued to William W. Somersall on Mar. 14, 1933, sets forth an upright, portable electric heater with air forced out radially at the top. This device humidifies occupied space by heating water contained above the heat source.
U.S. Pat. No. 3,775,590, issued to William Joseph Gartner on Nov. 27, 1973, describes a portable forced air heater which features a fan mounted toward the top of the heater, and which discharges air horizontally and radially from the top of the heater. Unlike the present invention, there is no significant degree of radiant heating provided by this device. Air flow is different in the present invention, passing through a reflector plate absent in the Gartner device. Also, Gartner locates a manual control near the bottom of the heater.
in U.S. Pat. No. 5,092,518, issued to Mituharu Tomioka et al. on Mar. 3, 1992, there is presented a combustion heater which features forced ejection of heated air. The thrust of the invention is to make constant the reach of projected heated air regardless of the amount of heat being dispersed.
A portable radiant heater is shown in U.S. Pat. No. 4,004,128, issued to Carlo Marchesi on Jan. 18, 1977. This heater surrounds a heating element with a thermal mass, which absorbs heat and radiates heat over a period of time extending beyond the period of time during which the heating element is energized.
A radiant heater described in U.S. Pat. No. 4,164,642, issued to Edward A. Ebert, on Aug. 14, 1979, is employed to heat eyeglass frames. A perforated metallic sheet is interposed between the heating element and an eyeglass frame. The metallic sheet absorbs energy of a given wavelength, and retransmits energy of another wavelength. Energy passing unobstructed through the perforations combine with retransmitted energy to assure that radiant energy of different wavelengths strikes the eyeglass frame.
The present disclosure provides a portable heater for providing radiant and convection heat. The heater includes a housing having an upper end, a lower end, a back portion and a front portion. An air intake is located at bottom of the back portion and a grill is located at the front portion forming an air outlet.
A heating element and reflector are positioned within the housing. The reflector is disposed between the heating element and a back portion of the housing. The reflector has a substantially oval shape, with the heating element being positioned within the reflector, the reflector at least partially surrounding at least of portion of the heating element. The reflector has a front surface capable of projecting radiant heat out of the heater through the grill. The reflector further includes an air vent arranged along a bottom portion thereof.
A blower is mounted within the lower end of the housing. The blower is interposed between the air intake of the back portion of the housing and the air vent in the reflector. The blower operates to propel air across the height of the reflector and the heating element. Electrical circuitry including blower controls is provided in the upper end of the housing. The electrical circuitry supplying power to the blower and the heating element. The heating element can be a closed loop heating element, including two “U” shaped heating elements.
The reflector is substantially oval in shape, forming a race track, having a raised center portion and a curved outside wall. The raised center portion and curved outside wall form a channel into which the heating element is positioned.
The heater provides a two-fold heating function, the heating element providing radiant heat and the blower causes air to pass in through the air vent, between the reflector and the heating element and between the heating element and the grill to expel heated air through the gill.
A more complete understanding of the present invention, and the attendant advantages and features thereof, will be more readily understood by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein:
Referring now to the drawing figures in which like reference designators refer to like elements, there is shown in
The back portion 16 of the housing includes an air intake 32, though which air is drawn into the heater 10, the air intake 32 being located at a bottom of the back portion 16. A pair of attachment clips 25 and 27 are centrally located on the back portion 16, such that the base 22 can be removeable attached to the attachment clips 25 and 27 for shipping. In this configuration, the footprint of the heater 10 is decreased, allowing for smaller packaging. In addition, the cord can be wrapped about clips 25 and 25 for storage.
Referring to
Referring also to
Referring to
Referring to
The outside walls 58 of the “W” shaped cross sections 54, 56 act like a “bowl” 60 where the combination of the “W” shaped cross sections 54, 56 and “bowl” 60 keep reflecting the light and heat produced by the heating element 30 until it passes beyond the grill 26. Furthermore, the combination of the “W” shaped cross sections 54, 56 and “bowl” 60 form a channel 62 through which the blown air travels, directing the heat away from the heater 10. The outside wall 58 of the reflector 28 can also be stepped 64, where the stepped walls 64 aid in the distribution of the heated air away from the heater 10.
The combination of the prismatic reflector 28 and the blower 40 provide a two-fold heating function. The prismatic reflector 28 directed the radiated heat energy outwardly from the beater 10 in all directions. The blower 40 forces air across the length of the heating element 30, both between the reflector 28 and the heat element 30, and the heating element 30 and the grill 26, where the shape of the reflector 29 directs the heated air outward from the heater 10.
The heating element 30 can be a closed loop heating element, or be formed from a pair of “U” shaped heating elements 66, 68 electrically connected. The heating element 30 is attached to the reflector 28 by support members 70. The support member 70 space the heating element 30 apart from the reflector 28, allowing the blower 40 to blow air between the reflector 28 and the heating element 30. The support members 70 can be made of a resilient material, allowing the heating element 30 to move with respect to the reflector 28. In this manner the resilient support members 70 can absorb impact energy during transport or a sudden dropping of the heater, thus helping isolate and prevent the damage to the heating element 30.
A reset button 27 is located on the back of the housing 16 and a thermal cut-out switch is mounted on the reflector 28. The location of the cut-out switch aids in the safe functioning of the heater. By placing it on the reflector surface, it is able to detect heat build-up which typically arises from being turned towards a wall or drapery or from towels or articles of clothing hanging nearby.
Thermostatic reset switch 86 is an automatic safety device comprising, preferably, a thermally responsive, snap action switch subjected to the heat from the front of the reflector 28. Switch 86 is located in series within the electrical circuitry so as to control all power. Switch 86 has a metallic element which flexes, or snaps, when subjected to a predetermined temperature. Flexure operates switch contacts (not shown), thus breaking electrical continuity at temperatures above the predetermined temperature. At temperatures below the predetermined temperature, the metallic element flexes back to its original position, and switch returns to a normally closed position.
A second lit indicator 88 (caution light) can be included which is placed in parallel with switch 86, and illuminates should switch 86 break contact. This signals that switch 86 has detected and responded to a potentially dangerous high temperature.
Thermostat 90 is manually adjustable, and operates by controlling all power flowing in the electrical circuitry. Thermostat 90 provides the user with control over the temperature at which heater 10 will operate. This control function is separate from the level of power output selected by switch 84. On-off control may be provided either by selecting an appropriate actuating temperature at thermostat 90, or by incorporation of an “off” position in switch 84.
Thermostat 90 can also incorporate a tip-over switch 92. Switch 92 is preferably a pendulum switch, which opens switch contacts when heater 10 is not in its normal, upright position. Switch 92 could comprise a mercury switch or any other suitable switch responsive to inclination of heater 10 from its normal, upright position. As a further safety feature, an over current device 94 is located in series within the electrical circuitry. Device 94 is a fuse or circuit breaker, as desired, selected to break all power responsive to detection of electrical current exceeding a predetermined magnitude.
Thus, it will be seen that both manual controlled switches 84 and 90, and automatic safety devices 86, 92, and 94, all are placed in series so as to control all power flowing within electrical circuitry. This arrangement effectively de-energizes all components, thus assuring safety regardless of the source of a potential fault.
All references cited herein are expressly incorporated by reference in their entirety.
It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described herein above. In addition, unless mention was made above to the contrary, it should be noted that all of the accompanying drawings are not to scale. A variety of modifications and variations are possible in light of the above teachings without departing from the scope and spirit of the invention, which is limited only by the following claims.
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/US12/63524 | 11/5/2012 | WO | 00 | 5/7/2014 |
Number | Date | Country | |
---|---|---|---|
61556928 | Nov 2011 | US |