US2523787A

US2523787A - Radiant fan heater

Info

Publication number: US2523787A
Application number: US106793A
Authority: US
Inventors: Jr David C Spooner
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1949-07-26
Filing date: 1949-07-26
Publication date: 1950-09-26
Anticipated expiration: 1967-09-26

Description

Sept. 26, 1950 D. c. SPOONER, JR 2,523,787

RADIANT FAN HEATER Filed July 26, 1949 Fig];

D is Attorney.

Patented Sept. 26, 1950 RADIANT FAN HEATER David C. Spooner, Jr., Westport, Conn assignor to General Electric Company, a corporation of New York Application July 26, 1949, Serial No. 106,793

5 Claims.

This invention relates to electric heaters, and more particularly to a device for heating by a combination of radiation and forced movement of heated air. I

An object of my invention is to provide an electric heater combining the advantages of radiant heating with heating by forced air circulation.

Another object of my invention is to construct an electric heater which radiates heat from a heating element in a concentrated beam while simultaneously providing forced circulation of heated air.

A further object of my invention is to provide a combination heat reflector and fan which is economically manufactured as a single unit and which permits reduction in overall size of the heating device while providing the same heating effect.

In accomplishment of the foregoing objectives, a feature of my invention consists in forming a combination heat reflector and fan from a single piece of sheet metal shaped as a heat reflecting bowl with deflected vanes around the peripheral edge, so that the reflector and fan element may be rotated as a unit to provide forced air circulation from the vanes without materially reducing heat reflection and radiation.

The features of my invention which I believe to be novel are set forth with particularity in the appended claims. My invention itself, however, both as to its organization and method of operation, together with further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawing, in which Fig. 1 is a sectional elevation of the apparatus; and Fig. 2 is a perspective view of the combination reflector and fan element.

Referring to the drawing, my improved electric heater is shown in Fig. l as including a. base I resting on a surface 2. For supporting the heater above surface 2, a trunnion 3 is adjustably affixed to base I and to a shell 4 enclosing the heating element and other operating parts. Shell 4, of substantially cylindrical shape, has mounted on one of its ends a front guard 5 made up of wire or other suitable material. The other end of shell 4 is covered by a rear guard or screen 6.

The heating element for my improved electric heater may be of a conventional type including a ceramic cylindrical core I having a coiled resistance wire 8 wrapped around its surface. The heating element is designed so that when it is operated on normal voltage, the resistance wire 2 is at a cherry-red heat. To support the heating element in the proper position, a cylindrical socket member 8, preferably of metal, is employed to receive an end of the ceramic core 7. Socket member 9, in turn, may be affixed centrally to front guard 5, thereby eliminating the need of any separate supporting members which block the radiation of heat and flow of air. Electric power is conducted to the heating element through a suitable cable Ill extending axially outward through ceramic core I and socket member 9. A conduit II, or other suitable cable concealing and protecting means may be employed for carrying the cable from the front or forward end of socket member 9 around the outside of front guard 5 to a suitable aperture in shell 4.

For electric heating apparatus to be effective, the heat from the electric heating element must be projected outwardly from within shell 4. Otherwise the heat given off would be dissipated locally and the heater would be inefficient. In accordance with my invention, I employ an ele-' ment which not only reflects heat radiated from the heating element 8 but which also directs a stream of heated air outwardly. Referring to Fig. 1, this combination reflector and fan element or bowl [2 is fabricated from a circular piece of sheet metal. Preferably, a metal is employed which may be buffed to provide a highly-polished reflecting surface. I find aluminum or copper coated with a. clear lacquer particularly suitable for this purpose, since neither of these metals are affected by rust and both may be highly polished for a reflecting surface.

Referring to Fig. 2, which is a perspective view looking into the heat reflecting bowl l2, a central aperture i3 is provided for mounting the reflector in axial alignment with heating element 8. The central or hub portion M of bowl I2 is flat to facilitate mounting. Extending from hub portion I4 radially outward is a curved surface l5. such as for example a parabolic shape, so that heat from element 8 is reflected in a concentrated beam from the surface of reflector bowl 12. Ex tending inwardly a small portion of the radial distance between the periphery of bowl l2 and the center thereof, the bowl is lanced to provide a plurality of vanes or fan blades I6 extending around the circumference. In the present instance, I have shown each vane l6 as subtending an arc of approximately 18 degrees, result ing in twenty such vanes or fan blades. I find. it preferable in this construction to utilize as much of the area of bowl l2 as possible for heat reflecting surface, and to limit the radial length of the fan blades or vanes to a minimum consistent with the desired flow of air. After the cutting operation to create the vanes or fan blades, the trailing edge Ifia of each blade is bent somewhat inwardly, and the leading edge I! is bent slightly outwardly. Thus as the fan is rotated, air is drawn in through the back screen 6, forced through the fan blades where it is heated in passing over heating element 8, and hence discharged forwardly as a heated air stream. At the same time, a substantial portion of the heat from element 8 is reflected from the bowl surface I5 in a concentrated beam to heat whatever object may be directly in front of the heater.

Mounted centrally within shell 4 is an electric motor I 8 with a shaft I9. A shaft hub is affixed to the combined fan and reflector I Zat its central aperture I3. Hub 20 carries a set screw 2I permitting the combined reflector and fan element I2 to be affixed to shaft I9. Therefore, when motor I8 is operating, the fan element I2- rotates to force air through this heating apparatus.

Electric power is supplied for the motor and heating element through a cord 22 having conductors 23 and 24. Cord 22 extends upwardly to a switch 25 for turning the heater on or off. A cord 26 from switch 25 supplies power to motor I8, and heating element 8 is connected in parallel through a cord 21.

From the above disclosure, it is seen that I have provided an improved electric heating apparatus which supplies heat not only by radiation from a reflecting bowl, but which also includes a fan to force a heated stream of air outwardly. This dual function increases the efficiency of the heating apparatus permitting smaller overall size for accomplishing the same heating effect. Also this dual function of heat radiation and forced hot air from a single heating element results from the use of a readily manufactured bowl which includes both the heat-reflecting surface and the fan blades. However, since the fan blades occupy only a small portion of the surface of the heatreflecting bowl, only a small portion of the heat is dissipated by reflections in all directions from the blades, most of the heat being concentrated into a beam by the central reflecting portion of this combined element.

While the present invention has been described by reference to a particular embodiment thereof, will be understood that numerous modifications may be made by those skilled in the art without actually departing from the invention. I, therefore, aim in the appended claims to cover all such equivalent variations as come within the true spirit and scope of the foregoing disclosure.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. An electric heater comprising a shell having a substantially cylindrical configuration, a base including means adjustably supporting said shell, a front guard affixed to said shell, a motor including a shaft therefor mounted centrally within said shell, a unitary reflector and fan member aflixed to said motor shaft and having a polished central circular surface of substantially parabolic form for heat reflection forwardly from the plane of said surface and said shell and vanes extending inwardly a small proportion of the radial distance from the peripheral edge to the center thereof to provide air movement forwardly with respect to said shell when rotated by said motor, and a heating element supported by said guard in heatreflecting relationship with said unitary reflector and fan member.

2. In an electric heater including an adjustably supported cylindrical shell open at both ends, guards on each end of theshell permitting through air movement while restricting access to the interior thereof, an electric heating element positioned centrally within the shell, and means directing the heat from the heating element outwardly in a concentrated pattern comprising a heat reflecting bowl receivable within the shell and having lanced vanes in a relatively narrow band formed around its peripheral edge, and an electric motor including a shaft therefor supported within the shell, said bowl being aflixed to said shaft for rotation upon motor operation, whereby heat from the heating element is both reflected as radiant heat and moved outwardly in a stream of warmed air resulting from rotation of said vanes.

3. In an electric heater including a heating element and a housing, a combined heat reflector and fan assembly comprising, a power means including a shaft, and a unitary reflector and fan blade element affixed to said shaft for rotation within the housing to reflect heat from and induce air flow past the heating element, said reflector and fan blade element having a central flat portion in axial alignment with the heating element and forming a hub attachable to said shaft, an intermediate curved portion of parabolic formextending over the greater portion of said element to concentrate the radiated heat into a beam, and a narrow peripheral portion cut and bent to form fan blades for moving air substantially in the direction of said beam.

4. A unitary combined reflector and fan member comprising a central hub forming portion adapted to be mounted on a rotating shaft, an intermediate curved portion extending over the greater proportion of the area of the surface ofsaid member to form a smooth uninterrupted radiant heat reflecting surface, and a narrowperipheral portion out and bent to form a plural ity of vanes for air movement upon rotation.

5. In an electric heater having an electric heating element and a motor mounted within a housing, means in the form of a bowl-shaped member for directing heat from said heating element in a concentrated pattern comprising a plurality ofvanes out radially inwardly from the peripheral edge of the bowl-shaped member and formed to provide a relatively narrow peripheral band of air moving blades, the remainder of the bowl-shaped member presenting a highly polished, smoothly curved, and uninterrupted surface for reflecting the radiant heat in a concentrated pattern. 1

DAVID C. SPOONER, JR.

REFERENCES CITED The following references are of record in the rile of this patent:

UNITED STATES PATENTS Number Name Date 1,335,423 Bonnaval Mar. 30, 1920 1,609,412 Kolisch Dec. 7, 1926 1,699,201 Guth Jan. 15, 1929 1,785,752 Vilas Dec. 23, 1930 1,914,724 Johnson June 20, 1932 1,967,757 Losee July 24, 1934 2,087,240 Brown July 20, 1937 2,303,447 Fay et al Dec. 1, 1942