US1174032A - Electric heater. - Google Patents

Description

w. s. IIAIIAwAY, II.

ELEC-TRIO HEATER. Y APPLICATION FILED FEB.I1. Isla. IIEIIEWED Aue. 2. I9I5.

Patented Feb. 29, 1916.

2 SHEETS-SHEET l.

W. S. HADAWAY, JR.

ELECTRIC HEATER.

APPLICATION FILED FEB. II. 1913. REIIEIIED AUG. 2.1915.

Patented Feb. 29, 1916.

2 SHEETS-SHEET 2.

WILLIAM S. HADAWAY, JR., 0F NEW ROCHELLE, NEW YORK.

ELECTRIC HEATER.

Specification of Letters Patent.

Patented Feb. 29, 1916.

Application :tiled February 11, 1913, Serial No. 747,635. Renewed August 2, 1915. Serial No. 43,345.

To all whom t may concern.'

Be it known that I, WIILIAM S. HAD- AwAY, Jr., a citizen of the United States, residing at New Rochelle, in the county of Westchester and State of New York, have invented new and useful Improvements in Electric Heaters, of which the following is a full, clear, concise, and exact description, reference being had to theaccompanying drawing, forming a part of this specificat1on. A

My invention relates to electric heaters.

, An object cf the invention is to provide improved means for securing a resistor to the object to be heated.

Another object is to provideV an improved method of integrally uniting a metallic resistor carrier to a body to which said carrier cannot be welded directly.

Further objects may be readily inferred from the more detailed description hereinafter given of the two embodiments'of my invention, which I have illustratedl in the accompanying drawings.

To aid in an understanding of said invention, I have shown one form of heater applied to a chaing-dish and the other form applied to a samovar. Either form of heater may, of course, be applied to either utensil or to any one of a number of other cooking or heating appliances.

Figure 1 of said drawings is a sectional elevation of the heating-pan of a changdish. Fig. 2 is a bottom plan view thereof. F 1g. 3 is an elevation of the entire chafingdish. Fig'. 4 is an elevation partly in section, of a samovar.

Fig. 5 is a sectional elevation of various parts of the heating element detached from each other to show the method of assembling; Fig. 6 is a bottom plan view of the resistance coil.

The @hating-dish is of the usual form except for the heating-pan or cooking-pan 1, which is of novel construction in certain lrespects in which it embodies my invention.

Said heating-pan, which is made of copper,

silver or other metal of good heat conductwith any degree of success from a commercial standpoint. In order to integrally unite the resistor container to the base,

which may be assumed to be copper, and to provide a good thermal contact between the two, I weld said metallic disk 2 to said container 3 through said copper bottom. One' satisfactory method of effecting this operation is to electrically weld said elements to each other over large areas, whereby they are integrally united through the copper base, thereby forming substantially an integral, unitary construction of high thermal efficiency. The metal disk 2 employed may be made of any of a number of different materials satisfactory for the purpose. For example, any of the alloys of the nickel group will answer, although I do not limit myself to this material. The sheet metal container 3 may be made of ordinary sheet iron or mild steel, although -certain grades of sheet iron are preferable to others. Of course, I do not limit myself to a resistance container made of the materials suggested.

The heating elements, which may assume various forms, are illustrated in the present instance as a pair of concentric heaters 5,-6. The inner disk-shaped heater 5 com,- prises a sheet metal disk or carrier electrically welded to the container 3 and to the disk 2, and has its edge bent over to embrace a smaller metallic disk 7. Between said disks` the resistor 8 is secured, said resistor being insulated therefrom by disks of insulating material 9,' for example, mica. The resistor may assume any one of a number .of different forms, the specific form being immaterial in the present case; Furthermore, either one or two superimposed resistors may be used. vThe outer heater has the form of a ring, made up of two flat metallic rings 10, 11, the wider one being electrically welded to the carrier 3 and the disk 2 and having its' edges flanged over the smaller one. A resistor or resistors 12,0f any suitable form, are held between said rings and insulated therefrom by rings 13 of insulating material. The resistors in both cases are held in close thermal contact with the base of the 'chaling `dish at all times, regardless of expansion and contraction. Of course, I do not limit myself to the use of two heaters. A greater or less number of heater units of any suitable shape may be used.

The resistance elements are inclosed by a cover plate 14 having a shallow annular` flange 15 which fits within the flange'4,

'The structure being water-tight, the entire pan may be immersed in water, in washing it. No reliance need be placed on any pressure which may be exerted upon the resistor carriers by the cover plate 14. In fact, said plate is intended, mainly, to provide a Water-tight cover and to act as a heating plate to heat the water in contact therewith, as hereinafter described.

The resistors are held in close heat conducting relation with the bottom of the heating pan 1, being separated therefrom by thin heat conducting layers of metal and in- 4 sulation which do not materially diminish the thermal eificiency of the device as a whole. Heat is conducted readily to. Nthe food within the heating pan and also to the Water in the water pan 16, within which the heating pan is partially immersed in the usual manner. Accordingly the food is heated by heat conducted directly vfrom the resistors through the bottom of the pan and it is also heated by water vapor which rises from the surface of the water and surrounds the side walls of the pan. Only a very little water is necessary or desirable under these circumstances as the heat is conveyed thereto from above and not from beneath the body of water. It is possible, therefore, to produce considerable heat locally at or near the surface of the water, from which surface vapor rises and it is not necessary to conduct a great deal of heat through the entire mass of water as in prior cases where a vapor lamp arranged beneath' the water bath has been employed. IVater being a poor conductor ofheat, greater eiiiciency results from heat applied from above rather than from beneath the same, where it is desired to make use of the ascending water vapor or steam.

The water bath also acts as a regulator to regulate the heat conducted tothe foodv pan and prevents overheating in substantially the same manner as in the old style changdish. The heat may be so Well regulated and controlled electrically, however, by the use of a suitable controller connected in circuit that, for certain purposes, the water pan may be dispensed with entirely.

The terminals of the resistors aresuitably connected to circuit terminals 17, the latter being mounted upon but insulated from the endof a metallic tube 18, the other end of which is attened out as at 19 and secured to the food pan as shown. A removable hollow handle 20 its over the tube 18 and protects said terminal 17.

Not only are the resistance elements firmly held in position within a water-tight casing independently of any pressure which may be exerted by the ycover 14, but the entire `heating element is very thin, compact and ornamental, and the outline of the structure is such that its appearance does not differ materially from the appearance of an ordinary chaing-dish.

In Fig. 4 I have illustrated a samovar having an electric resistance element secured thereto as an integral and permanent part thereof, said resistance being secured in a mannerl somewhat similar to that just described. Within the receptacle 21 and against the copper or silver base 22, I place a metal disk 23 similar to the disk 2 previously described, and weld said disk to .a sheet'metal carrier 24 having an annular flange 25. A suitable resistor 2G is arranged within said carrier and insulated therefrom by mica disks 27. The resistor may assume most of the heat upwardly to the liquid within the samovar.

Suitable circuit terminals 32 are provided, which are carried by said cover plate 31, but are insulated therefrom by mica washers 33 arranged on opposite sides of a horizontal supporting flange 34, said terminals being headed over or riveted to the mica washers. A pr tecting casing 35 is provided for the terminals, said casing serving as a guide in connecting an attachment plug, and comprising a short metal tube having its upper end ianged outwardly and secured to the cover plate 31, preferably by welding.

It is to be understood, of course, that the invention is not limited to the two embodiments thereof described and illustrated, nor to their use with utensils of the kind illustrated, as various other forms may be devised and various changes made in the details of construction referred to herein, without departing from the spirit of the invention as expressed in the appended claims.

What I claimas new and desire to secure by Letters Patent of the United States is 1. In a device of the character described, a metallic resistance carrier, a body to be heated against which said carrier is located, and a metallic element arranged on the opposite side of said body, said element consisting of material adapted to be welded to said carrier, said metallic element and said arrier being welded together through said 2. In a device of the character described,

a metallic container for a resistance, a body to be heated against which said container is located, a metallic plate of material adapted to be welded to said container arranged on the opposite side of said body, said plate and said container being integrally united to each other through said body, and a resistance Within said container and insulated therefrom.

3. In combination, a sheet metal carrier is arranged, a metallic plate on the upper side of said body, said plate being welded to said carrier through said body, a resistance adapted to fit Within the annular flange of said carrier, mica insulation on opposite sides of said resistance, and a cover plate beneath said resistance and insulated therefrom by said mica, said flange being bent inwardly to firmly secure said resistance in intimate heat-conducting relation with said body, whereby a compact unitary construction is provided.

4. The combination with a cooking utensil having a depression in its base, of a metallic plate fitting within said depression, a sheet metal container conforming substantially to the outline of said plate and arranged in contact with the under surface of said base, a cover 'plate fitting said container and a resistance arranged between said container and said cover plate and firmly held thereby, said container being integrally united to said metallic plate through the base of said utensil.

5. An electrically heated chafing-dish contact with the under surface of said de` pressed portion, a metallic plate having a thickness substantially equaly to the depth of said depression and fitting within the same, said carrier being welded to said plate through the base of the chafing-dish whereby it is integrally united thereto, a resistance in the form of a thin flat disk arranged within said carrier, a shallow flanged cover plate tting within said carrier in inverted position, mica disks arranged on opposite sides of said resistance to linsulate the same from its metal support, said cover plate being welded to said carrier to provide a water-tight inclosure for said resistance, a hollow handle for said chafing-dish, and circuit terminals therein, said terminals being electrically connected to said resistance.

7 In combination, a heating plate, a container integrally united thereto and a plurality of concentric resistance carriers integrally united to said container, said container having a cover integrally united thereto, whereby said carriers are inclosed in a water-tight casing but are held independently of said cover.

8. In combination, a metallic plate of good thermal conductivity, a plate of less thermal conductivity on one side thereof and a metallic resistance container also of less thermal conductivity, on the opposite side thereof, said container being electrically Welded to said second plate through said first plate, and a resistance carrier electrically welded to said container.

9. In combination,` a metallic plate of good thermal conductivity, a plate of less thermal conductivity on one side thereof and a metallic resistance container also of less-thermal conductivity, on the opposite side thereof, said container being electrically welded to said second plate through said first plate, a resistance carrier electrically welded to said container, and a cover integrally united to said container to provide a water-tight inclosure for said carrier.

l0. In an electric heater, resistors, carriers therefor, and a pair of metallic plates be tween which said carriers are arranged, said carriers being welded to one of said plates and arranged conccntrically with respect to each other;

1l. in electric heater, resistors, carriera therefor, and aV pair of metallic plates between which: saidicarriem. are aranged, y said Lampes carriers being; Welded:` to one of said plates nesses.

and arranged concentrically withzrespect to each other,v said plates being united at' their 5 edges to form aa water-tight. inolosure for'- said resistors.;

In witnesswvhereof, I have hereunto sub- Correction in Letters Patent No,I 1,7174,0132`1.\

WLLIAM s. HADAWAY, JR.

Witnesses :v

EDWIN LIGHfrFooir,l Gr.1 P.. BBoeKwA-Y.

Itis hereby certified that in Lettersl letentv No. 151745032, granted February 29, 1916, upon thev application of. William S. Hadaway, Jr., of- New Rochelle,

` New York, for an'` improvement in Electric Heaters, an error appears in the printed specificationv requiring eorreetion as'- follows: Page 3,. line 45,. claim 4,

I after the Word meta insert -the Word resistance; and that the said Letters tent should bereaid with this correction therein that the same may conform I to the record of the case in the Patent Ofoe.

signe-d and Sealed @his 18th day of April, A. D., 1916.

[SEAL] R. F. WHITEHEAD,

Actin Commissioner o Patents. Cl. 21g-44. g l f scribed n1jyfnarre-r` in the presenceof two Witv

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