May 29, 1956 s KQZBELT 2,748,247
INFRARED DEVICE Filed April 10, 1953 2 Sheets-Sheet 1 Fig.1
INVENT /2 gym 5. KOZB INFRARED DEVICE Lloyd S. Kozbelt, Pittsburgh, Pa., assignor to Edwin L. Wiegand Company, Pittsburgh, Pa., a corporation of Pennsylvania Application April 10, 1953, Serial No. 347,929
1 Claim. (Cl. 219-34) My invention relates to an infrared device, more particularly to an infrared device having a sheathed-type electric resistance element, and the principal object of my invention is to provide new and improved devices of the character described.
The wide usage of electric infrared devices in modern day industries is well known. These devices find application wherever it is desirable to employ a concentrated, clean, easily regulated source of heat for purposes such as drying and the like. In the past, glass infrared lamps have been employed; however, these lamps have not been entirely satisfactory.
Some of the disadvantages of the commonly used infrared lamps are as follows: Since infrared lamps are constructed of glass, they are easily broken if they are struck by an object or if they are splashed with water or other liquid when hot. Infrared lamps also have a relatively short life which will be further materially reduced if the lamps are subjected to shock or vibration.
In contrast, an infrared device constructed in accordance with my invention possesses none of the disadvantages possessed by prior art devices. Other advantages of my invention will be understood from a study of the following description and of the drawings appended here to.
In the drawings accompanying this specification and forming a part of this application there is shown, for purpose of illustration, an embodiment which my invention may assume, and in these drawings:
Figure 1 is a fragmentary plan view of an infrared device embodying my invention,
Figure 2 is an elevational view of the embodiment shown in Figure 1, certain parts being broken away to better illustrate interior construction,
Figure 3 is an enlarged fragmentary sectional view generally corresponding to theline 33 of Figure l, and
Figure 4 is a further enlarged fragmentary sectional view generally corresponding to the line 44 of Figure 3.
As illustrated, my improved infrared device comprises a sheathed electric resistance element in combination with a reflector 11 and aterminal mounting block 12. The element It is constructed in accordance with Wellknown principles and comprises atubular sheath 13 filled with compacted refractory material in which is imbedded the usual coiled resistance wire. In the present embodiment, the coiled resistance wire terminates short of respective ends of the sheath and each end of the resistance wire is secured to arespective terminal pin 14 that extends from a respective end of thesheath 13 to provide for a terminal connection later to be described.
As will be understood, the portion of the sheathed element 10 intermediate the ends and containing the coiled resistance wire is commonly known as the active or heat generating portion. In the presently disclosed embodiment, this active portion is formed to provide a generally rectilinear portion having a pair of arcuate portions disposed in the plane of the rectilinear portion, each arcuate portion extending from a respective end of the rectilinear 2348,24? Patented May 29, 1956 portion and curving back toward the opposite end of the rectilinear portion. As shown, this construction provides a compact ray-generating area having a configuration substantially that of the figure 8 and which is substantially flat and which will radiate infrared rays in a uniform pattern that is devoid of dead spots.
As illustrated,leg portions 15 extend from the active portion of the element 10 and the leg portions are adapted to be secured together by means of aclip 16. In the presently disclosed embodiment, theclip 16 is formed of sheet metal or the like to provide a generallyplane portion 17 having spaced-apart apertures each adapted to receive arespective leg 15. As best seen in Figure 4, each leg portion extends through a respective aperture in theclip 16 and is secured thereto, as by brazing or any other suitable means.
With reference to the position of parts shown in Figure 4,opposite portions 18 of theclip 16 are each bent to a position underlying theportion 17 and generally parallel therewith, eachportion 18 being further bent downwardly to provideportions 19 which lie in respective planes that are angled toward the axes of theleg portions 15 as shown. As will be clear, theclip 16 serves to secure theleg portions 15 together and also serves other purposes which will later be shown.
As illustrated in Figure 4 and as previously mentioned, eachterminal pin 14 extends beyond the end of itsrespective leg portion 15. Acoupling sleeve 26 is disposed about eachpin 14 and each sleeve is secured to itsrespective pin 14 in spaced relation to arespective leg 15 by any suitable means such as, for example, by crimping the sleeve at 21. Dielectric means such as a plurality ofmica washers 22 are interposed between each sleeve and itsrespective leg 15 in order to space the sleeve from the leg.
Each sleeve 2%? extends beyond the end of itsterminal pin 14 to form a pocket for receiving an elongated flexible electrical conductor or pig-tail lead 23. Eachlead 23 is adapted to be disposed in its respective pocket and each may be secured in place by silver solder or other suitable means.
As previously mentioned, and as shown in Figures 1 and 2, the element 10 is adapted to be used in combination with a reflector 111 and aterminal mounting block 12. The presently disclosed embodiment illustrates the reflector 11; as formed integrally with a sheet-metal,boxlike reflector housing 24. It will be apparent that a plurality of reflectors could be formed in a single housing or that any other suitable construction could be employed.
The housing 24- is apertured at 25 (see Figure 2) to receive theblock 12, the block being secured to the under surface of the housing as shown, by means ofscrews 26 which pass through apertures in the housing and are threaded into the block.
The block 112 is provided with aboss portion 27 intermediate its ends (see Figures 2 and 3) and such portion extends through theaperture 25 in thehousing 24. As best seen in Figures 3 and 4, theportion 27 is recessed to provide opposedinclined walls 28, and the block is provided with spaced-apart apertures 29 for a purpose to be disclosed. Opposite ends of theblock 12 are recessed at 30 to receiveterminal clips 31 that are secured to the block by means ofscrews 32.Channels 33 are formed in the lower surface of theblock 12 and each channel extends from one of theapertures 29 to an adjoining recess 3d.
The element 10 is adapted to be supported by theblock 12 in fixed relation with the reflector 11 in the following manner: Thelegs 15 of the element 10 will first be inserted through anaperture 34 in the reflector Ill so that the sleeves 2t) and theleads 23 are disposed Withinrespective apertures 29 and whereby theportions 18 and 19 of theclip 16 respectively abut the upper surface of theblock portion 27 and theinclined walls 23 of the recess formed in theportion 27. As will be clear, the active orheat generating portion 13 of the element 1% will thus be correctly positioned with respect to the reflector 11, and particularly, the active portion will be maintained in predetermined spaced relation with the plane of the outer surface of the reflector.
As clearly shown in Figure 3, the element is adapted to be secured in position to theblock 12 by fastening the free end of each of theleads 23 to a respective terminal clip by any suitable means, eachlead 23 lying in arespective channel 33 ofmounting block 12 as shown. The electric powerline may then be connected to theterminal clips 31 in order to eiiect operation of my improved infrared device.
in view of the foregoing it will be apparent to those skilled in the art that I have accomplished at least the principal object of my invention and it will also be apparent to those skilled in the art that the embodiment herein described may be variously changed and modified, Without departing from the spirit of the invention, and that the invention is capable of uses and has advantages not herein specifically described, hence it will be appreciated that the herein disclosed embodiment is illustrative only, and that my invention is not limited thereto.
I claim:
An infra-red device for use in heating by radiation, comprising a bowl-like reflector having a central aperture, an elongated metallic-sheathed electrical resistance element disposed in fixed position within the reflector bowl, said element having an intermediate heat generating portion of configuration like the figure 8 including a rectilinear central portion and two oppositely disposed arcuate portions disposed in a common plane and respectively continuing from opposite ends of said rectilinear portion and curving back to the ends of the latter opposite to the ends from which the respective opposite arcuate portions originate, said rectilinear portion being disposed between and connecting said arcuate portions in the plane thereof, said resistance element further including a pair of coplanar straight non-heat generating sections respectively continuing from said arcuate portions and disposed in spaced parallel relation to and on opposite sides of said rectilinear portion, the free ends of said straight sections being bent into a plane normal to the plane of said heating portion of the element and disposed in spaced proximity to constitute terminal portions extending through said reilector aperture for connection to a source of electrical energy, whereby said intermediate radiant heating portion of said resistance element is co-extensive only with said rectilinear central portion and the opposed connected arcuate portions, said straight sections and said terminal portions of the element being relatively free of heat to minimize mutual heating between adjacent parts of said resistance element.
References Eited in the file of this patent UNiTED STATES PATENTS 1,393,368 Henry Oct. 11, 1921 1,531,414 Ruben Mar. 31, 1925 1,580,090 Schoenberg Apr. 6, 1926 2,068,423 Manser Jan. 19, 1937 2,161,793 Beaucolin June 13, 1939 2,303,873 Anderson Dec. 1, 1942 2,325,358 Andrews July 27, 1943 2,455,186 McCormick Nov. 30, 1948 2,514,618 Ancell July 11, 1950 2,615,117 Tillapaugh Oct. 21, 1952 2,712,587 Story July 5, 1955 FOREIGN PATENTS 680,553 Germany Aug. 31, 1939