US985144A - Electric oven. - Google Patents

Description

J. V onown ELECTRIC OVEN.

APPLICATION I ILED NOV. 29, 1909.

985,144. Patented Feb. 28, 1911.

UNITED STATES PATENT OFFICE.

JAMES v. CHOWN, on OAKLAND, cALIFonNiA, ASSIGNOR OF ONE-SIXTH 'ro R. PORTER GILES, ONE-SIXTH T0 WILLIAM s. COX, onn-srx'rnc T0 J. CLEM AnY, AND ONE-HALF T0 JESSIE MARIAN cnown, ALL on OAKLAND, CALIFORNIA.

ELECTRIC o vnn.

Specification of Letters Patent. Application filed November'29, 1909. Serial No. 530,331.

Patented Feb. 28, 1911.

My invention relates to electric ovens or.

heating chambers wherein the heat used for cooking or other purposes is generated through the medium of suitable electrical resistance.

The object of the invention is to provide a simple, cheap, economically-operateel,

' practical oven, particularly designed for household purposes to take the place of the ordinary gas stove or oven which is so injurious to health, and in which oven or heating vessel I employ a latent heat-holder or retainer into which the heat is absorbed as the oven is gradually heated up; suitably insulating this latent heat-holder from the outside atmosphere so that after a suiiicient heat is obtained in the oven a part of the .current may be cut off, and a sufficient cooking heat will be maintained through the remaining small current used, and the reserve supply of heat stored in the latent heat holder, and which is gradually returned to the oven.

The invention consists of the parts and the construction and combination of parts as hereinafter more fully: described and claimed, having reference to the accompanying drawings, in which Figure 1 is a longitudinal section of the invention. Fig. 2 1s a plan view of the same.

My oven, as actually constructed and successfully used, consists of an outside wall A of suitable material, such as diatomaceous earth, carbonate of magnesia, or other non conductor of heat. I prefer to use diatomaceous earth, or a mixture of diato'maeeous earth,.;sawdust and lime, since experience shows that this is an exceedingly good heat insulator. These walls A are of suitable thickness to'su'ccessfull y prevent the radiation of any heat enei'ated within the bakin chamber 2. T is oven is preferably pro vi ed with a door 3 of the same material as the walls A, and the door may be hinged at one side and made with step joints, as shown, ,so that when. the door is closed practically tained within the oven. Both the walls A all the heat generated by the coil 4: Will be re andthe door 3 of the oven-are lined on the inside, as shown at 5, with a suitablelatent heat-holder, such as soapstone or fire-clay,

either of which has the quality of absorb ing the heat, This lining 5 is in marked contrast to the outside insulating wall A, and the distinction is one to be carefully borne in mind. The outside shell A prevents the heat from passing beyond the heat absorbing and retaining lining 5, so that if the-heat in the coil 4L is cut off orreduced and the oven allowed gradually to cool, the heat stored in the lining will be given backinto the oven, rather than allowed to escape to the outer atmosphere and be lost. Preferably the lining 5 is covered on the inside of the oven by a metal shell 6 which is in the nature, more or less, of a good conductor of heat and does not interfere with the return radiating action of the .heat stored in lining 5 back into the oven.

Any suitable form of electrical heater 4 may be employed, and the interior of the oven may be provided with removable shelves 7 and ribs 8 for the support of such shelves.

The metal lining is preferred, as it keeps the odors generated within the cooking chamber from penetrating, into the more or less-absorbent lining 5, and makes the oven easy to clean.

If desired, a thermometer 9 may be attached to the ovendoor, so as to indicate to the operator the temperature of the oven chamber 2.

In order to give stability to the structure and prevent the composition of the oven walls being broken or injured, I employ in practice a skeleton frame-work of iron or wood, and represented in the drawings by the corner pieces 10 anddiagonal pieces 11.

In practical operation, the article or articles to be cooked are put into the oven,

chamber and the door 3 securely. closed.

Preferably the coil 4 is connected with a suitable electrical controlling device, as the rheostai'. 100, whereby when the heat is first.

turned onthe full curTent will be allowed to pass through the coils, so as quickly to heat up the oven chamber. When the temperature of the oven chamber has been raised sufficiently and the absorptive lining 5 highly heated, the rheostat can be turned so -as to regulate the strength of the current through all of the coils a reduced current, when supplemented by the reserve supply of heat stored in the latent heat-holding lining'f), being sufiicient to maintain the oven at a proper temperature.

It is understood that the sides, ends, and top and bottom of the oven chamber are surrounded by this latent heat-holder 5 in the outside insulating shell A.

Having tlius' described my invention, what I claim and desire to secure by Letters Patent is-/ An elec 'ric oven comprising a shell embodying annixture of diatomaoeous earth,

Gopies of this patent may be obtained sawdust and lime, and having its interior lined with a coating of fire-clay, sn id composition and lining inclosing an oven chamber, a door of like composite material similarly lined closing said oven chamber, an electric heating coil for the oven, with means for regulating the amount of heat from the outside' In testimony whereof I have hereunto set my hand .in the presence of two subscribing witnesses.

JAMES V. CHOWN.

Witnesses:

RAYMOND A. LEONARD, CHARLES EDELMAN.

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