US1108890A

US1108890A - Oven.

Info

Publication number: US1108890A
Application number: US73351812A
Authority: US
Inventors: Ransom W Davenport
Original assignee: DETROIT STOVE WORKS
Current assignee: DETROIT STOVE WORKS
Priority date: 1912-11-25
Filing date: 1912-11-25
Publication date: 1914-09-01
Anticipated expiration: 1931-09-01

Description

R. W. DAVENPORT.

OVEN..

APPLICATION rum Nov. z5, 1912.

1, 108,890. Patented Sept. 1, 1914.

7155-671 esseg UNITED STATES PATENT OFFICE.

RANSOM W. DAVENPORT, F DETROIT, MICHIGAN, ASSIGNOB TO DETROIT STOVE WORKS, OF DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN.

ovnN.

Specification of Letters Patent.

`Patented Sept. 1, 1914.

Application filed November 25, 1912. Serial No. 733518.- I

America, residing at Detroit, in the county of XVayne and State of Michigan, have invented certain new and useful Improve-1 ments in Ovens7 of which the following is a specilicatiom reference being `had therein to the accompanying drawings.

v The invention relates to ovens, being more particularly designed for use in connection with electric heaters.

It is the object of the invention; first, to obtain an effective heat insulation; further to utilize the heat generated in one oven chamber either for heating .the same or an adjacent oven 7chamber; and still further to obtain a convenient and effective arrangement of vthe heating elements.

vWith these objects in view, the invention consists in the construction as hereinafter set forth.

In the drawings: Fig. 1 is a perspective View of the oven, pratly broken away; Fig. 2 is a cross section; Fig. 3 is an enlarged section showing the arrangement of the heat-reflecting and nonconducting elements of the heat insulation; Fig. l is a view similar to Fig. 3 showing a modified construction ;y Fig. 5 is aperspective view of the lamp and its fitting; and Fig. 6 is a vcross sectionthrough one of the heating units.

A is theoven casing, which preferablyk in.- closes two supcrposed oven chambersB and C the un ier chamber constituting a bakin 7 .t I D g oven7 and thc lower chamber a broiling oven. D and D are electrical heating units arranged respectively at the top of the chambers B and C, and in a position to radiate:

their heat downward.

E are doors at the front of the oven chambers B and C.

To make the most ellective use ofthe heat generatedy inthe units D and D,` the construction of the walls of the oven chamber' is such as to form an effective heat insulation. This` I preferably secure by combining alternate reflecting and non-conducting layers as, follows: F is an inner layer or lining of the oven, which is formed of some good heatconductin material-such as sheet aluminum. Adjacent to this lining is a non-con-V ductingl layer. formed in any suitable way, as;

'wit-h, is

by the a for instance, by a cellular `body G whichvl prevents circulatlon'of the air. Beyond this .non-conducting medi'umis another bright heat-reflecting surface I' andy then anotherl non-,conducting medium G and another heat-reflecting surface'l. This alternation of reflecting and non-conductin layers may continue. to any extent desire) the outer case J being formed of any suitable material ihaving the proper strength and. rigidity.

This construction insures partial reflectionl of the 'incident radiating hea-t at the surface F, while that portion of theradiated heat abscrbedby the relector,'-together with the heat derived from the air incontact theredprevented from .rapid dissipation )acent non-conducting medlum'G, This non-conducting medium will cause av drop in temperature between its `faces S0` that the second heat-reiecting surface I will oe at a lower. temperature than the-first surface F. lVith each succeeding alternate reflecting surface and heat-insulation .there will be a drop in temperature so that a very` ell'ective heat-insulation is obtained. Where, the oven is used for ordinary cooking oper-Y ations the temperature within thechamher will never rise to the point which will melt or destroy the aluminum sheets, and therefore this material, which has the property of. retaining a bright surface even when heated to a considerable extent, best adapted for the inner lining; andf the outer reflecting Surface I, being always at' a. relatively low y temperature, canbe made. of' tin or other bright metal whichmwculdbe discolored if subjected to .the inner-oven tempera-ture.

c On the other hand Where the oven is `used for operations requiring ,a A.higher tempera- "ture which would .be destructive Ato the aluminum (plate-s,l as well asl` to all other ava ilahle bright surfaces, I form the -inner lining -0f K, or other suitable material, and place` a non-conducting layer L immediately adjacent thereto, beyond which is the bright heat-reflecting surface F; as shown.

in Fig. 4.. The principle employed in both constructionshown Figs. 3 and 4., is to, placejthe: heatelepting surface as near the.

sourceof heater inner lining of the oveli chamber as is said surface. ,i

-The'heating units 'D and ,DT are prenten: ebhc constructed .se to, produrerect heat Without destroying radiation into the oven chamber from as large a portion of the resistor as possible. To secure this effect the heat resistor M is preferably in theform of a coil wound upon an electrical insulating` core M, lwhich eX- tends horizontally adjacent to the top wall of the oven chamber, and this core is preferably substantially triangular in cross section, with the apex downward. By reason of this shape two-thirds of the resistor M will be arranged at angles permitting of direct downward radiation of the heat, while only one-third passes above the core and radiates heat upward. rl`he heat radiating upward is reflected downward again `by the bright lining F, but there is Aa loss due to the imperfection in tlie reflector, which is avoided in the portions of the resistor radiating directly downward.

In the lower oven chamber C, constituting the broiling oven, a reflector N, preferably of aluminum plate, is arranged above the heating unit D, to reflect downward any upward radiation from said heater. This reflector N does not, however, form a perma nent portion of the partition between the ovens B and C, but said partition is formed Vby a plate O of dark metal-such as ironwhich is a poor reflector and a good heat radiator. iIhus whenever it is desired to use the heater D for heating the bottom of the oven B, the reflector N is removed from its position between said heater and partition O, and is placed below the heater D, as indicated by the dotted line N Fig. S2. This will reflect the downward radiation from the heater D upward, and as the partition O is of metal having dark Aabsorbing' surface, being. both a good heat radiator and heat conductor, the upwardly directed heat radiation will pass easily into the chamber B.

As electrical heating units are destructible it is desirable to mount the same so that they may be conveniently removed and replaced. This I accomplish by forming in the side wall of the oven casing a channel P, in which the electrical conductors 13 for connection with the heating units are placed, and which also contain insulator blocks Q containing the terminal contacts. The heating units, including the core member M and the resistor M wound thereon, are insertible through apertures Q in the blocks Q, and the outer ends of said units are provided with terminal contacts It for engaging with the corresponding contacts on the blocks Q, thereby completing thel connection of the'unit with the electric circuit. The contacts R are preferably mounted upon a vhead member M2 of the core member M, and are-insertible in sockets QZ in the blocks Q,

thereby effecting not only the electrical 'connection but also a mechanical coupling. The rods M2 as well as the blocks Q, lie within the 'recess P, and when 'the parts'are'in posi incasso tion a cover plate P2 is secured to the oven casing to close the recess P. Thus at any 'time when the resistor of one ofthe units is burned out, it may be removed and replaced without skill or electrical knowledge on the part of the operator. A series' of blocks Q is arranged in the channel P, and in addition to those which are employed as the heating units one or more of these blocks may be used for the connection of an electric light-such as S, Fig. 5-the bulb of which passesthrough this aperture Q and illuminates the interior of the oven.

In operation, the electric circuits for the heating units are controlled by suitable switches, not shown, and may be used for heating either or both of the oven chambers B and C as desired,

`What I claim as my invention is:

l. In anoven, a casing divided into a plurality of chambers, suitable heaters ar: ranged therein,a heat reflecting shield adjustable to positions upon opposite sides of one of said heaters, a heat insulating wall, comprising a bright, metallic heat reflecting plate, positioned in said wall at the nearest point to the inner surface which is at.a temperature below that which is destructive to the bright surface, and a heat non-conducting layer adjacent to the said heat refleeting plate. q l

In an oven, a casing divided into adjacent separate chambers, a heat insulating wall. comprising a bright metallic heat reflecting lining formed of material non-corrodible at the oven temperature, an adjacent layer of heat non-conducting material, an outer reflecting metallic plate of a material corrodible at the temperature of the 'wall in the position `in which it is located, and a plurality 'of recesses arranged in one of the walls of said oven and adapted to 4 receive-suitable heating' units.

3; Inj an oven, a casing divided into a plurality of oven chambers, a heater in one of said chambers adjacent to the partition between the same and the other chamber, and means for directing the heat of said heater alternatively into the chamber'in which it is located and into the adjacent chamber.

4:. In an oven, the combination with a casing, divided into adjacent separated chambers, of an electrical heater in one of said chambers adjacent to the partition between Athe same and the otherlchamber, and an imperforate partition between said chambers, adjustable to vary the penetration of heat therethrough.

5. In an oven, the combination with a casi ing, divided into adjacent oven chambers, of an electrical heater in one of said chambers adjacent to the separating partition,

of good heat-absorbing and radiating `fnaterial, and a heatreecting`shield remor-l an imperforate partition having a surface ably placed between said heater and partition.

6. In an oven, the combination with a casing divided into adjacent oven chambers, of lan imperforate partition between said chambers formed of a good heat-penetrating material, an electric heater in one of said chambers adjacent to said partition, and a heat-reiiecting shield adjustable to positions upon opposite sides of said heater.

7. The combination 'with an oven having a recess in the Wall thereof, of xed electrical terminal contacts located in said recess, and an electrical heating unit insertible through an aperture in said recess into the oven casing,` and having cooperating con tacts for engaging with said fixed contacts.

-8. The combination with an oven casing having a channeled Wall, of electrical conductors located in the channel of said Wall, a series of terminal contacts connected to 4said conductors and also located in said channel7 a plurality of electrical 'heating units insertible through apertures in said channel into the oven chamber, contacts on said units ior coperating with the fixed contacts in said channel, .t rernnra; ie cover for sald channel.

a heat insulating Wall, oompriain a bright metallic heat reflecting. lining perature, an adjacent layer of heat nonconducting material, and an outer reecting metallic plateof a material corrodble at the temperature of the wall in the position in which it is located.

10. ln an' oven, heating units arranged therein, a heat insulatin wall, comprising a bright, metallic heat-re ecting plate; p`ositioned in said Wall at the nearest point t0 the inner surface which is at'a' temperature below that which is destructiveuto the bright surface7 and a heat non-conducting layer adjacent to said heat-reilectin plate.'

` In testimony whereof I a my signature in presence of two witnesses.

RANSOM W. DAVENPORT.

Witnesses:

JAMES P. BARRY, ADnLAmn I. ADAMS.

' Uopies o! this potent :any be obtained for ivo conta non, by honing the Commissioner of Patents,

, Wallington, D. 0.

9. In an oven, heaters arranged therein,v

o rmed of material non-corrodible at the oven ternv