US2644443A - Oven liner - Google Patents

Description

JUlY 7, 1953 A. BARNsT-EiNER 2,644,443

OVEN LINER Filed oct. 18, 1949 2 sheets-sheet 1 BY W ATroRNEY July 7, 1953 A. BARNSTEINER 2,644,443

y OVEN LINER Filed Oct. 18, 1949 2 Sheets-Sheet 2 8 26 /0 ILT/6.5. /4

INVENTOR WITNESSES:

ALFONS BARNSTEINER temperature conditions.`

Patented o July 7, 14953 tigris Alfons Barnsfreiner, Mansfield? Ohio;

i 1, rburgh, Pag;

` Application carotene, liaseriai No2-122,105

' Thisinvention relatesto an'iovenliner fabricated of sheet metal, and has'- for an object'to `provide 4an oven liner that has greater' resistance to distortion stresses, Which-may be incurredfdu'ring its manufacture andin baking and lother -cooking processes. f l It isa further object of thisinventionlto! provide'a sheet metal oven liner -havingaf-more rigid front end member;thus-assuring an--improved and more uniform -door seal under- @all vcooking It is'another'objeqtrortiiis invention to provide 1an fimprovedfoven liner that can bef'manufactured atnoincreasein cost. .5

in'llorder to insure goo -bakin'gfiesuits man oven, uniform heat l'distribiition throughoutthe oven interior must be maintained! iilthugh 'various factors must be takenfinto-account in manufacturing an oven havingfV/uniform-baking qualities, one of the most important 'and'hereto'f `v`fore troublesome factors hasfbeenftheprovision Vo f'fan oven'in which the door/seal remainsuni- Vform under all baking conditions.A YDue'Y to'- un- 'even 'expansion and Warpage'of the'1in' aifip`onl "heating,v air leakage through lthe door-toliner sealwould vary with varyingfoven temperatures,

AWithin the ovenV p 4 In; 'accordance With ymy invention; :I formv lthe 'oven liner With-corner portionsadjacent'the' Open upsetting and impairingproperjri at lristripudon n* ora'fcrm to serve as corner-braces to resistvvv'arp- 'age or distortion.' Thesecorner portions are'dis vposed relatively :close to thel intersection of the r`adjacentf.v'valls l'at theffront 'end and'fthenffare Ispacedprogressively further 'from such intersecn ftion in rearward direction,. 'Bre'ferably, the goor"- fV her portion is of minimumradi'us'at thevfront endv and of progressively greater radius 'in'rearward direction. 'The Yfront end portion of thej liner thus provided is of larger cross-sectional ydimenslons at'its iorward'end thanatitsrearward end, ta'c'ilitating its' removal from the dies. No', necessary bulges are present thatvvqnild` nkecessi tate the use of special dies or other tools.'v` Such corner portions can 'bev Vformed in the drawing of lthe front end portion of the ovenv liner, and are thereby provided without anyv ad:ditionall operation and without any increase` in cost.

'In the drawings, y l Y.

` Figi is atop plan of a dravvnl sheet-metal pan 'member which provides the front end member and the rear Wallmember of an oven liner;` f Fig.- 2 is an elevational view ofthe pan member;

' '5 claims. f

front end ofthe liner, -vvhichfcorner'portionsr are I Yigl3 is)1 fa fragmentary section-.takenzonline -1rI;-'Iir.ofrrig 1.;;f t g, t Fig.- Liis-a section takenon line IV-IVoffFig; 3;;

Y Y tFig;-:5 isa longitudinal section ofthe completed f Y fragmentary perspl I tive lview,v show- Jing ac ornerfbrac'eportion..

Y .f Referring tou (the.V drawings' 1n' detail and esi--r pecially Eig. 5; atfabr-icatedy sheet metal oven liner. f

im designated /I'llfisy .shownffcomprising a'itubular Wrap-around body memberelZ having al'top wai-1 ma vbottomwall y:l s and `two 'side Wausla r (only peripheral'ange v314' adapted to bei abutted by 'closing the joven liner When in use;y ItsA toy be understood that for the oven tolhav'e 'good baking properties it is essential thatf'thesea1at the iiange be unaiected bytemperaturechan 'As best 'shown-in liigsgi and ZQaQpreIimmary pan-like structure 38,` of. fgenerallyi',rectangulara set of lsuitable dies Atial`stagejofffabric ti severing",y Athese imembers areformedv respectively,

, 's 26fand22 which ei/endg,- o A between adjacent .side Walls' arev curvdto provide smooth vcurved surfaces lollv and *toVv eliminatefcorfhswhh; are @iff-@1t i0 9182.11: Als-0, the 'juridtipnsivbiweenfthgbottom 40 andthe SideWalls f2 maybe .curved -forthesame reasons. v`A prelimi- 'fnary peripheral ,-f1ange 46.9f substantially iqee-v loven# door ('not'shown)V and'toact 'as aseal for tangular shape, is disposed adjacent the walls 42, and is provided by the unformed sheet metal during the drawing process.

As well understood in the art, the structure 38 may be drawn to shape in one single drawing operation. If desired, at various spaced portions, the walls 42 may be formed with a plurality ofl integral kgusset-like indentations 48 which extend into the flange 46 to stiien the flange in a conventional manner. At each corner adjacent the flange 46 there is formed a curved portion 5D joining the adjacent Walls .42

and the curved surface 44. Since the four curved portions 50 thus provided may beidenti'cal, only one Vsuch portion will be described` in detail, i-t being understood that the other portions will be similarly formed. As best 4.shown `in Fig. 4, the curved portion 50 is disposed within the angle formed by the intersection Y of the planes of the adjacent walls 42. Its rear end conforms tothe curvature of the rounded surface 44, which has a relatively large radius R1. The front portion -is disposed more yclosely to the intersection Y of the planesyof the walls V42. -It is more sharply curved than the portion 44 andmay -desirably be formed on the arc of a circle having a shorter radius R2. Intermediate its front and rear ends, the curvature ofthe portion 5Dvchanges gradually and smoothly from the short radius of curvature at the front lto the larger-radius of curvature at the rear. Thus, the portion 50 is outwardly inclined with vrespect to the rounded surface 44 by an angle V13 and has a substantial area when :projected in a plane parallel to the Wall 40, as shown in Fig. 4, thereby possessing a substantial corner bracingjeffect. It willbe noted that the curved portion 5i) is substantially .tangential to the adjacent walls 42.

The shape of the portion 5D may be formed in any desirable manner andneed not follow any exact mathematical form. For example, it may be formed, in whole orin part, as a frusto-conical surface having the Acenter F--Fl andV having radii R3' and R4 at the front. and rearends of the corner portion. Suchform has the advantage that the concave surface of the matrix hence the walls 32 still maintain their plane appearance and the rectangular aspect of the opening is preserved.

As fully explained and claimed in Barnsteiner et al. patent application, Serial No. 116,901, led September 21, 1949, after the oven liner I has been assembled and spot-welded into one rigid unit, as previously described herein, the preliminary 'flange 46 is reformed tothe L-shaped flange 34.

. Although I haveshown and described only one embodiment of the curved portion 5U, other shapes which may be attained in drawing and or intaglio die (notshown) may belformed byv a rotating cut-ting tool, insteadofbyjlaborious `and, less exact methods. Obviously,the junctions between the frusto-conical surface thus formed and the walls 42 may be blended together to provide a smooth contour to the finished oven liner. As well understood, the matrix die may be dressed at these junctions to Y impart the smooth contour.

A strong bracing 'effect' is thus limparted to the adjacent walls and flangeto form a .rigid structure which is highly resistantto bending or warpage. It will be noted that the curved surfaces are Iinclined outwardly with respect to the curved surfaces `44, `thus permitting the pan 'structure to be easily .formed in a die and to be removed therefrom. The added bracing `'eflett is vthus attained without any increaseY in, manuf'acturing costfsinc'eV no added manufactur? Subsequent warpage-of the-liner uponf forming dies may be found advantageous, the chief requisite, Ias explained above, being that the portion V5|) be inclined outwardly relative to the rounded surface 44, with its front portion disposed more closely to the intersection Y than its -rear portion.

What I claim is:

1 ,Av fabricated sheet metal oven liner 4for a range comprising a front end member having a tubular portion, said tubular portion having top, -botto'm and side walls defining a vsubstantially rectangular throat opening, an intermediate tubular body member joined to said front end member, and a rear end closure member joined to said bodymember to provide a substantially cubical structure openat the front, said -f-ront en'd member having an loutwardly extending peripheral flange, each adjacent pair of said walls having a curved portionv at their junction, each lrange comprising a front end member yhaving a tubular portionlsaid tubular portion having top, ybottom and side walls deini-ng a substantially rectangular throat opening, an intermediate tubular Abody joined at one end to said front member and a rear end wall member joined to .the other end of said body member to provide a substantially cubical structure having an opening :at the front,l said front end member hav,- ing an outwardly extending peripheral flange,

each adjacent pair of said top, bottom `and sidey walls beingv disposed substantially in planes disposed at a right angle to each other., said adjacent walls having a ,rst curved portion and a second vcurved portion at their. junction, said first curved .portion being adjacent said flange andbeing inclined inwardly in av direction toward said rear wall, at a'n angle to the axis of said second curved portion, said rs't'curved portion lying wholly within the .right angle formed by the intersection of said planes and serving as aY corner -brace 'to resist warpage 'or distortion ofthe liner.

3. The structure recited in claim 2 in which 'said nrs't curved portionis a frusto-conical surface of increasing radius in a direction toward saidrear'wall. j

4. A sheet metal oven liner comprising top, bottom, side and rear walls providing a substantially cubical casing having an opening at the front, a jfront peripheral flange disposed outwardly atfan 'angle to said top, bottom and side walls, each adjacent pair of said last-mentioned walls having a curved portion at their junction, each said curved portion being adjacent said flange; and having a surface of increasing radius Zin -a direction toward said vrear wall 'and being inclined outwardly in the opposite direction, whereby said curved, portion serves as a corner brace to resist warpage or distortion of the liner:

5. A sheet metal ovenl liner for a range comyWall and blending substantially tangentially with said adjacent walls to provideV a smooth and prising top, bottom',l side and rear Walls pro- 5 viding asubstantially cubical casing open at the front, a front peripheral flange extending out. wardly at an angle to said top, bottom and sidev walls, each adjacent pair of said last-mentioned Vwalls having a rst curved portion zand a second curved portion at their junction, said rst curved portionfbeing adjacent said flange and being inclined outwardly with respect to said second curved portion, said rst curved portion` being substantially frusto-conical and increasing in radius in a Ydirection toward said rear rigid structure.

ALFONS BARNSTEINER.

References Cited in the file of this patent- UNITED STATES PATENTS Number Name Date `2,253,499 Rutenber Aug. 26, 1941 2,349,751 Piker 1-..- May 23, 1944 2,367,007 Cossin Jan. 9, 1945 FOREIGN PATENTS Number Country Date Y Norway 1- Oct. 16, 1939

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