US2479425A - Portable electric space heater - Google Patents

Description

Au'g- 1949. G. ISTEINGRUBER I 2,479,425

PORTABLE ELECTRIC SPACE HEATER Filed May 17, 1946 4 Sheets-Sheet l n I n u a 5 i a 1 Aug. 16, '1949. G. STEINGRUBER PORTABLE ELECTRIC SPACE HEATER 4 SheetsSheet 2 Filed May 17, 1946 mm mm mm Wm wm aw UH VF w mm m6 Q Q 0m A Q @v f\\ on @N 0% mm Q Q J mwd m Q r Q m m 1w 0 MN MN .MW OW N ma wvmw Aug. 16, 1949. G. STEINGRUBER PORTABLE ELECTRIC SPACE HEATER I 4 Sheets-Sheet 3 Filed May 1'7, 1946 Aug. 16, 1949. G. STEINGRUBER PORTABLE ELECTRIC SPACE HEATER 4 Sheets-Sheet 4 7 Filed May 17, 1946 vone direction :so .as -;to confine it to Patented Aug. 16 1949 2,479,425 PORTABLE ELECTRIC SPACE HEATER George Steingrtiber, Atlanta, Ga. Application May 17, 1946,;Serial 'No. 670,385

, iiims. 1

The present invention relates ;to electricheaters,andmore.particula,rly,:to:apewandzimpmtttd portable electric space :heater having :for its iprlimary objects, among .others, simplicity of .con- 'struction and assembly, compactnessiin -size, lightness in weight, :highefiiciency and economy :in operation, and @neatness and attractiveness ,of appearance.

A efurther principal .object of :the invention is :to :provide anelectric heater of the :aiOrernen- -'tioned type which is constructed practiqally wholly of sheet metal, :the component parts ;of which are ireduced '-=to a minimum inumber, and each part :having :the eform 10f :a sheet metal stamping and zhaving provision for simply and quickly attaching ithe same together mechanicallyiin assembled form, ilargely without screws :or other separate fasteners, ;and wi thout resort to welding .or other relatively .expensivezoperations requiring specialiskllls.

A still ifurther object of *the invention is -,t o provide a new and improved portable electric heater .utilizing in combination ;the principles of heat reflection, radiation, and circulation, and through which air is circulated by indu t on fi with superior. efiectiveness, without r sort --.,to one- .chanical aids, such asl fans .or blowers.

Another important and vprincipaleobject ,of the invention isto provide anew andimproved portable ,electric :heater :which is .so ;.const ?ucted and arranged as to direct the heat .in r spectively opposite directions from opposite sidesi or facesv of :the heater, with the additional provision for se- 'lectively .blocking the .heat discharge, at will, .in discharge at one side onlyoftheiheater.

:Other and further objects and advantages of ':the invention .willtbe hereinafter described and the novel features-thereof defined by the-appended claims.

:In the drawings .Figurel is a view,. partlyinl elevation, and partly inxsection, of an electric heater constructed :in

accordance with the :present invention;

Figure 2 .is a vertical sectional view taken .on the line 12-12 otlligure i=1;

Figure 3 is a horizontal sectional view taken on the .line 13-4 ,of Figure 12;

Figure 4 is a fragmentanyssectional:detail \view on an enlarged scale, taken on the line 4:4 .01 Figure :1, showingzthe manner .in which the marginal edge of the grille is :inserted :between the outer shell andtheend walll'ofethe inner reflector assembly;

:Eigure 5 .is aldeveloped plan -viewoi a sheet ,2 smeta ;s am inez mmwhi the a e .Q theheate is iform d a a se rate ron ni c 21 11 1;

Figure 6 i ia' devc o e pla new -,o f a she m a tam n wh chfo m th e l cu ed heat flow dividing ;reflecting deflector which extends r m s de-l ovs nd be we t ef e grend wa ls W t i th runne por o cf the at s;

Figure 7 is a developed plan view ;of :a sheet metal stamping fromiwhich is formed onerofithe two-stationary defiectorsdocatedinthe lower;portion of the;heater;

Eignre ,8 is a developed plan view v'of a sheet metal stamping irorn which is formed the outer s el o c in ;o th hea r; and

Figure ,9 is a developed plan view of a sheet :metal stamping from which is ,formed oneof the two reflectinggendvwalls of the reflector-assembly.

Like reference characters ,designate ,corresponding partsin theseveral-figures of the-draw- ,go .ings, in which Figures 51 to .4 inclusive illustrate the heater ,in its assembled form, and Eigures .5 to :9 inclusive illustrate typical sheet metal ,stampings from which certain of the component partsof theheaterare formed. The heater will 25 be ,first generally described with reference to Figures ,1 ,to l ,inclusive, wherein .i denotes the base of the heater Which-is formed ,preferably in one piece f rom a sheet metal stamping. The base {is generally rectangular in horizontal :plan, and at :the :four corners thereof, the base is extended ,downwardly to.prov,ida legs 2. .At the'lower ex.- .tremity of each leg, there is preferably provided .-a spherical ball-like foot 3 toraisethelegsslight- .ly above thesfioor or other surface on whichthe :heater is supported, to ,prevent the legs from scratching {or ,otherwise :marring the supporting surface.

connectcdzto thebase unit I and-extending up- ,wardly lfrom the upper sides ,thereof is a pairof laterally spaced .end walls :5, ,5. As will be best seen iirom reference toFigure 3, .each end wall iis bent laterally "outwardly from the vertical central portion thereof sothatthe opposedend walls i diverge outwardly irom each other at the 'respec tively-opposite sides.of acentral transverse plane through the heater. fI-he-npperend of each end wall5 'is,n0t ched ..or otherwiseicut away, ,as -at-6, -.Vf 0r:the ,purpose which iwill hereinafter more fully ap a Extending laterally from side to side ibetween vtheend walls?5,=5 ,;and connected thereto in any su table mann r is a versa s cu ed hea -fl dividi d fle to Wa ene all es e lTlh wa l *1 p ef rabl :made n one piece f om sheet metal, and itslower end gs5iSj1QQ8/tQd a subside walls I8, I8 together.

stantial distance above the upper side 4 or platform of the base unit I. From the lower end of the wall I, the wall extends upwardly and forwardly and upwardly and rearwardly respectively at opposite sides of a central transverse plane through the heater. The curved portions of the wall 1 are respectively indicated at 9 and III.

The preferred means for attaching the wall I to the end walls 5, preferably have the form of integral tabs or ears designated I I which extend through slots I2 formed in the respective end walls 5, 5. In assembling the walls, the ears II are inserted through the slots I2, and then the ears are bent over upon the end walls-so asto lie flat against the outer faces of the same, thereby firmly attaching the walls together without the aid of welding or otherexpensi've'operations. The end walls 5, 5 are preferably attached to the platform 4 at the upper end of the base member I, in the same manner, for which purpose,the end walls are each provided with tongues or ears I3 which are adapted to extend through slots I4 provided in the platform 4. After insertion of the ears I3 through the slots I4, the ears are bent over beneath the platform 4, and serve to rigidly attach the end walls to the base member-I, with the end walls disposed'in an upright position.

The end walls 5, 5, and the reversely curved heat-flow dividing deflector 'I are preferably made of a material which may be given a high polish on at least the inner faces thereof, that is, the inner faces of the end walls 5, 5, and the concave faces of the curved portions 9 and III of the deflector I. If preferred, these faces may be i plated or otherwise finished, such as by means of chromium'plating, to act as reflector surfaces.

As will be understood from the foregoing, the base member I, together with the end walls 5, 5, and the heat-flow dividing wall I, when assembled, form a unit defining above the platform 4 of the base member I two chambers respectively designated -I5 and I5,'one of these chambers lying at one side of a central median plane through the heater, and the other chamber Y,

lying at the opposite side of the median plane. The unit is enclosed withinan outer shell or casing generally designated II, this shell extending upwardly from the base member I at the opposite ends thereof, in spaced relation to the side walls 5,5, forming outer sidewalls I8, I8, and also forming a top wall I9 abovethe upper extremities of the end walls 5, 5 and joining the The outer casing or shell I1 is provided along its opposite marginal edges with flanges respectively designated 20,20, these flanges being bent inwardly and lying at right angles to the end walls I8, I8 and the-top wall I9, thereby giving to the outer casing a U-shaped form in cross section; At the lower ends of the outer shell or casing I'I, the flanges 20, 20 are overlapped upon the base member I and are secured to the base member in any suitable manner, as by means or screws 2|. The inner marginal edges of the flanges 2U, 20 are preferably overlapped upon outwardly bent flanges 22 which are provided on the vertical edgesofeach of the end walls 5, 5, at the front and back of these walls, the flanges2ll, 20 being extended inwardly from the end walls 'I 8, I8 to the inner surfaces of the respective end'walls 5, 5, and forming at the front and back respectively of the heater substantially rectangular openings through which the heat may be discharged from the heater at the front and at the back thereof.

Suitably secured to the top wall I9 of the outer casing II, as by means of screws 23, is a handle 24 by means of which the heater may be readily carried. It will also be noted that the wall I9 is provided with a pair of elongated slots 25, 25, located respectively at opposite sides of the handle 24, which serve as vents for the chamber 25 located in the upper portion of the heater, above the reversely curved heat-flow dividing wall 1. This chamber 25 is also in open communication with chambers 21, 21 at the opposite ends of the heater, these chambers being defined by the spaced walls 5, 5 and I8, I8, the communication being established by the notches or cut-outs 5 in the end walls 5, 5. The purpose of these vents 25, 25 is to prevent the entrapment of heat within these chambers, the vents allowing the heat to escape readily from the chambers and thereby keep the temperature of the outer casing II relatively low. Accordin ly, the outer casing will remain cool and safe to handle, as, well 'as eliminating any possibility of fire-hazard should garments or other inflammable objects come into contact with the casing accidentally.

Mounted in the lower portion of the heater, and extending from side to side between the end walls 5, 5, approximately midway between the upper base plate or platform 4 of the base member and the lower extremity 8 of the heat-flow dividing curved deflector I, is a heating element generally designated 28, said heating element being of any suitable form, but preferably comprising a porceleain or other refractory mounting 29 of tubular form, having electrical resistance wire 30 wound thereon. The central axis of the heating element 28 .is located on the central median plane through the heater, so that the heating element is disposed directly below the lower end 8 of the deflector I, thereby causing the heat generated bythe heating element to be equally divided by the member I, with approximately one-half of the heat deflected forwardly by reflecting the heat in a generally upward direction. The longitudinal marginal edges of the plates SI, 32 are preferably flanged as at 33 to stiffen the plates, and each plate is provided with a plurality of tongues or ears 34 at the opposite ends of the same to interlock with slots 35 formed in each end wall 5, 5 in a manner similar to the connection of the reversely curved wall I with the 'end walls-5,5. One of the deflector plates, as for example 3i, carries a pair of terminal posts 35', 35, each of which extends through the plate and is insulated therefrom, as by means of a porcelain bushing 35 received in an opening 3? in the plate. The electricalresistance wire 35 of the heating element 28 is connected at each end to the respective terminals and the terminals are in turn connected to a suitable extension cord 38 which ma be'plugged into any convenient electrical outlet or other source of power supply.

For conveniencein mounting the heating element 28, the base plate or platform 4 of the base member I is preferably provided with two upwardly offset supporting arms 39 which are preferably struckout from thebase plate as an integrh part thereof, the base pate being f rme or sheet metal. mine only one or the rms 39 is shown in Figure 1, it will be understood that a second arm is provided at the opposite end of the base plate, hear the end wall 5. g n v Mounted on the upper sides of the arms 39, and extending laterally from side to side between the end walls 5, 5 isa horizontally disposed baffle 40, the marginal edges of which are preferably one positely and upwardly inclined in an outward direction, as indicated at 4|, 4|. This heme may be attached to the arms 39 in any suitable man-- ner, as by means of screws 42. At the extreme ends of the baffle 40, the bafile is extended upwardly in theform of upright arms 43; there being the; of said upright arms at each end of the baffle. An annular boss 44 is struck out from each arm 43 in an inward direction and serves to engage in the end of thetubular insulated support 29 of the heating element 28. The extreme upper end of each arm 43 is provided with a bendable tab or tongue 45 which is adapted to be bent outwardly against the end wall 5 at each end of the heating element 28, when the heating element has been mounted between the arms 43, 43; Since the Walls 5, 5, and the arms 43, including the tongues 45, are all preferably time of sheet metal, they will be relatively resilient or springy, so that when the heating element 28 is mounted between the arms 43, 43, and the tongues 45 are bent into engagement with the end walls 5, 5, the heating element 28 will be more or less yieldingly or resiliently supported, which serves to protect the heating element against undue shock during handling of the heater, as well as allowing for expansion of the heating element without damage to the same.

In order to allow air to freely enter the heater, the base plate 01" platform 4 is provided with a plurality of openings 46 which are distributed substantially over the entire area of the base plate. In striking out the supporting arms 99, this leaves relatively large openings 41 in the base plate beneath the arms, and in addition, there is preferably provided another large opening 48 between the openings 41. Air can therefore freely enter the bottom of the heater, not only at the bottom of the chambers I5 and I8, but also at the bottom of the chambers 21, 21. The hori- 'zontally disposed baffle plate 40 serves to prevent the air from passing directly into contact with the heating element 28, which might unduly cool the heating element, and causes the air to flow around the baflle, and thence upwardly around the heating element. As the air is heated, it rises upwardly and is divided in opposite directions, and the heated air will be discharged partly at the front and partly at the back of the heater in the normal position of operation.

In order to selectively control the air flow and heat discharge through the heater, there is preferabl provided a movable bafile or closure mem ber 49'. This baffle 49 has the form of a curved plate which extends from side to side between the end Walls 5, 5, and is provided at each end with an arm 50 which is pivotally connected at 5| to the upright heating element supporting arm 43. Swinging movement is imparted to the member 49 in any suitable manner, as by means of a lever arm 52 which is pivotally connected at a mid-point, as at 53, to a tongue or ear struck upwardly from the base plate or platform 4 of the base member i. The upper end of the lever arm 52 is disposed in abutting contact with the outer face of the baflle member 49,- and the lower 6 end of the lever arm is pivotally connected at 54 to an actuator bar 55 which is extended rer= wardly through the front face of the base mere: ber which is provided with a slot or opening 55 through which the actuator bar 55 is freely slidable. The outer end of the actuator bar 55 terminates in an operating handle 51, and the actuator bar is preferably provided with a notch 58 which may be interlockingly engaged with the edge of the slot 56 to positively lock the actuator her in its outwardly extended or manipulated position. Normally, the movable baffle 49 will assume the position shown in full lines in Figure 2 of the drawings, dropping to this position when the handle 51 of the actuator bar 55 is shoved inwardly} By pulling the handle 51 outwardly, the heme member 49 will be causedto rock in a counterclockwise direction, as viewed in Figure 2, tin-til its flanged upper edge 59 comes into engagement with the lower portion of the curved wall 9 of the heat-flow dividing wall 1, as indicated by the broken lines and the arrow in Figure 2. When in this position, the baflle member 49 serves to block off the heating element 28 from the chamber l5,so that all of the heat generated by the heating element will be confined to chant her [6 at the opposite side of the heater. Under such conditions, the heater may then be placed near a wall, or in a corner, or hear some other object with the blocked side of the heater next to the same, without danger of overheating the object or setting the same afire. To restore the heater to a condition causing the heat to be discharged from both sides thereof, it is simply necessary to push the handle 51 of the actuator bar 55 inwardly so as to rock the lever 52 to the position in which the upperend of the lever abuts the stationary deflector plate 32, thereby allowing the curved deflector 49 to drop by gravity to the full line position shown in Figure 2. The deflector 49 preferably has its inner face polished or otherwise finished to give the same good reflecting qualities.

When the heater is in use, that is, when the heating element 28 is energized, the resistance wire 30 becomes incandescent and glows. The glow effect is reflected in the associated reflecting walls, and by reason of the outwardly diverging arrangement of the ends walls 5, 5, the reflection is multiplied so as to produce a plurality of refiected images of the heating element, thus giving the effect of a plurality of heating elements in the heater, and creating a very pleasing and attractive illusion. I

In order to prevent the clothing or other inflammable objects from accidentally getting too close to the heating element 28, such as might cause the same to accidentally catch on fire, the heater is provided at each of its opposite sides with a grille or guard designated 69, the grilles extending over the area of the generally r'e'tahgular openings at each side of the heater, and preferably being bowed outwardly so that the outer side of each grille is spaced substantially outwardly from the face of the heater proper. The shape and design of the grille may be varied to suit individual preferences from the standpoint of attractiveness, and by reason of the outwardly bowed arrangement of each grille, the grilles minimize the possibility of setting the floor or other supporting surface and floor coverings afire if the heater be accidentally tipped over. The grilles may be attached to the heater in any suitable manner, such for example, as by providing the marginal edges of the grille with flat bars 61 at oifgthe respective curved deflector walls 8 and Ill,

the latter flange being designated 6;. While the bars (it around each grille will be securely wedged between the flangesas just described, provision isbrefeiablymade forpositively preventing displacement of the grilles, as by disposing the lower bar 'Bl. upon the outer face of the bottom mernber, Land securing the bar to the bottom member nleer ehl nn ra by tr sfik I the kcept ion of a f w of the parts of the heater, the heater is wholly composed of sheet from sheet metal blanks as illustrated in Figures to 9 inclusive. After the blanks have been stamped out and bent into the shape of the component parts, they can be quickly and easily asmetal, and the component partsmay be stamped 'sembled with a minimum of effort and without any Welding whatsoever, which is particularly advantageous from the standpoint of low cost of production of the heaters, and eliminates the use of specially skilled labor. The construction of the heater also reduces the number of component parts to a minimum, while attaining the advantages of high efficiency and economy of operation. L f-ls a' further precaution against the danger of contact with the electrical terminals particularly when the heater is used around children, a steam guard plate 64 is disposed in an upright position at; that side of the heater where the ter- .rninals are located, with the guard plate disposed the outer side of the-terminals and extending upwardly from the base plate or platform 4, to a point near the upper edge of the stationary deflector 3|. The guard plate is of such a size as toblock offthe zone in which the terminals 35 are located, and thus prevent children from stickingtheir fingers through the grille 60 into contact with the terminals 35. If preferred, the guard .64 may have decorative perforations 65 therein, but such perforations should be small or very narrow so as not to'permit the entrance of a childs finger therethrough.

While the specific details have been herein shown and described, the invention is not confined thereto as changes and alternations may be ,made without departin from the spirit thereof as defined in the appended claims.

, I claim:

, 1. An electric heater of the class described, comprising a base member having legs formed at the bottom thereof and a horizontal base plate at the upper side, a pair of laterally spaced end wall members carried by the base member and extending upwardly from the base plate aforesaid, with the-respective end wall members spaced inwardly from the respective ends of the base member, a deflector member connected to the aforementioned end wall members and extending laterally therebetween, said deflector member being reversely curved from a point above the base plate and substantially on a lateral median plane through the base member, to provide a forwardly and upwardly curved deflector portion and a rearwardly and upwardly curved deflector portion, an outer casing extending upwardly from the bottom of the base member at its opposite en s. to. a po nt abov he u p e re it es of the I endw'all members, i said leasing. includingfa top wall arranged hor'i'zontally above the end wallmembersandjthe reversely curved deflector memberjand 'also'including'side walls spaced outwardly from the end walls aforesaid and'definin an air chamber therebetween and an electrical heating element arranged substantially horiao'n tally between the end wall members intermediate the lower, extremity fof the reverselycurvedlde fiector member and the base plate, with the heating element disposed on the central median plane 'of the base member.

2. An electric heater as defined in claim 1, wherein the end wall members are provided with bendable tongues extending through openings in the base plate of the base member, for rigidly connecting the end wallmembers to the base p a e. 1 I

3. An electric heater as defined inclaim l, whereinthe end wall members are provided with bendable tongues extending through openings in the base plate of the base member, for rigidly connecting the end wall members to the base plate, and the reversely curved deflector member is also provided with bendable tongues extending through openings in the respective end wall members for rigidly connecting the deflector member to the end wall members.

4. An electric heater as defined in claim 1, wherein the outer casing is provided with marginal flanges overlapping the base member at the front and back thereof and secured thereto.

5. An electric heater as defined in claim 1, wherein the outer casing is provided with marginal flanges defining heat outlets of substantial area at the front and back respectively of the heater, between the end wall members.

6. An electric heater as defined in claim 1, wherein the outer casing defines another chamber above the reversely curved deflector member and communicating with the pairof chambers between the respective end wall members carried by the base member and the side walls of the outer'casing.

7. An electric heater as defined in claim .1, wherein the outer casing defines another chamber above the reversely curved deflector member and communicating with the pair of chambers between the respective end wall members carried by the base member and the side walls of the outer casing, and the base plate of the base member is provided with a plurality of openings for admitting air into the respective chambers and into the space between the end wall members below the heating element.

8. An electric heater as defined in claim 1, wherein the outer casing defines another chamber above the reversely curved deflector member and communicating with the pair of chambers between the respective end wall members carried by the base member and the side walls of the outer casing, and the base plate of the base member is provided with a plurality of openings for admitting air into the respective chambers and into the space between the end wall members below the heating element, the top wall of the outer casing having an air outlet opening formed therein.

9. An electric heater as defined in claim 1, wherein theouter casing is provided with marginal flanges defining heat outlets of substantial area atthe front and back respectively of the heater, between the end wall members, and a grill mountedweneaoh heat. outlet.

10. An electric heater as defined in claim 1, wherein the outer casing is provided with marginal flanges defining heat outlets of substantial area at the front and back respectively of the heater, between the end wall members, and a grille mounted ver each heat outlet, with the marginal edges of the grilles inserted behind the marginal flanges of the outer casing at the opposite ends and at the top of each grille, and the lower marginal edges of the respective grilles being attached to the base member.

11. An electric heater as defined in claim 1, in combination with a movable deflector member pivotally supported intermediate the end wall members at one side of the heating element for movement towards and away from abutting contact with the lower end of the reversely curved deflector member.

12. An electric heater as defined in claim 1, in combination with a movable deflector member pivotally supported intermediate the end wall members at one side of the heating element for movement towards and away from abutting contact with the lower end of the reversely curved deflector member, and acuator means for moving said last-mentioned deflector member as aforesaid.

13. An electric heater as defined in claim 1, in combination with a movable deflector member pivotally supported intermediate the end wall members at one side of the heating element for movement towards and away from abutting contact with the lower end of the reversely curved deflector member, and the surfaces of the end wall members, the reversely curved deflector and the movable deflector, which face the heating element, being characterized as reflecting surfaces.

14. An electric heater as defined in claim 1, wherein the end wall members outwardly diverge with relation to each other at opposite sides of the central median plane through the heater.

15. An electric heater as defined in claim 1, in combination with a baflie plate disposed horizontally below the heating element in spaced relation to the same.

16. An electric heater as defined in claim 1, in combination with a baffle plate disposed horizontally below the heating element in spaced relation to the same, said bafile plate having an arm extending upwardly therefrom at each end thereof, with means on said arms to engage and support the heating element between said arms.

17. An electric heater as defined in claim 1, in combination with a baffle plate disposed horizontally below the heating element in spaced relation to the same, said baffle plate having an arm extending upwardly therefrom at each end thereof, with means on said arms to engage and support the heating element between said arms, said arms being disposed in spaced relation to the respective end wall members, and having bendable portions at their upper extremities to yieldingly engage the end wall members when bent into contact therewith after mounting the heating element between the arms.

18. A portable electric space heater, comprising an outer casing open at the front and at the back thereof. a base member including a horizontal base plate disposed adjacent to the bottom of said casing, a pair of laterally spaced upright walls arranged within said casing and extending upwardly from the base plate to the top of the casing, a reversely curved wall disposed between the upright walls and spaced above the base plate, with a portion of said reversely curved wall extending upwardly and forwardly from a point substantially midway between the front and the back of the casing, to the front of the casing, and with another portion extending upwardly and rearwardly to the back of the casing, a horizontally disposed heating element arranged below the reversely curved wall aforesaid and in spaced relation to the base plate, said base plate having provision for admitting air therethrough into the casing to be heated by the heating element and subsequently discharged at the front and back respectively of the casing, and a movable deflector member pivotally mounted adjacent to the bottom of the casing above the base plate and at one side of the heating element, said movable deflector extending laterally between the upright walls and being movable towards and away from abutting engagement with the reversely curved wall to selectively block the discharge of heat from one side of the casing, while confining the head discharge to the 0pposite side of the casing.

GEORGE STEINGRUBER.

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

UNITED STATES PATENTS Number Name Date 1,836,253 Johnson et al. Dec. 15, 1931 1,934,565 Siers Nov. 7, 1933 2,232,492 Steingruber Feb. 18, 1941

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