US2387939A

US2387939A - Floor furnace

Info

Publication number: US2387939A
Application number: US448273A
Authority: US
Inventors: Olds Ambrose Dean
Original assignee: Coleman Lamp and Stove Co Ltd
Current assignee: Coleman Lamp and Stove Co Ltd
Priority date: 1942-06-24
Filing date: 1942-06-24
Publication date: 1945-10-30
Anticipated expiration: 1962-10-30

Description

Oct. 30, 1945.

Filed June 24, 1.942

5 Sheets-Sheet 1 3 7 O! M m z a LIWI 0 i i 3 l w 1. 4 "I w H m x 6 1m a w X, @M H 7 6 I 8 l a W 8 6 9 w 6 I! .4 j 7 5 3 u w l \I/ Q j M 4 m 4 l 5 if H l M a a 7 3 "a III INVENTOR ATTORNEY 0a. 30, 1945. A. D. 01.05 2,387,939

FLOOR FURNACE Filed June 24, 1942 3 Sheets-Sheet 2 63 IETOR Hmb 056 0 0/081 @M mu ATTORN EY Oct. 30, 1945. A. D; LDs 2,387,939

FLOOR FURNACE Filed Jl me 24, 1942 3 Sheets- Sheet 5 J at INVENTOR fimbrose 0. 0/03 wwm ATTORNEY Patented Oct. 30, 1945 FLOOR FURNACE Ambrose Dean Olds, Wichita, Kans., assignor to The Coleman Lamp and Stove Company, Wichita, Kans, a corporation of Kansas Application June 24, 1942, Serial No. 448,273

Claims.

This invention relates to floor furnaces, and more particularly to an inner casing and liner construction therefor. It is well known that furnaces of this character are noisy in operation for the reason that uneven expansion and contraction of the inner casing and its liner cause large flat areas thereof to buckle and snap out of their normal positions.

Therefore, the principal object of the present invention is to provide an inner casing and liner construction which permit uneven expansion and contraction without producing objectionable noises.

Other objects of the invention are to provide a liner composed of a plurality of sections each having independent movement relative to the other; to provide the liner sections with channel-like ribs that are formed therein to accommodate linear expansion and contraction of the intermediate plane portions of the sections in a direction transversely of the ribs; to provide for relatively loose connection of the expansion ribs with the inner casing to accommodate expansion of the sections in a direction longitudinally of the ribs; and to provide slight spacing of the adjacent edges of the liner sections so that the sections may move to and from each other without touching and creating buckles therein as might be the case when expansion of one section is limited by an adjacent section.

Other objects of the invention are to provide an inner casing and liner assembly loosely suspended within the outer casing; and to provide a relatively strong casing structure having flexibility at the corners to further reduce noises incidental to buckling of the side walls of the casings caused by their inability to have some movement relatively to each other.

In accomplishing these and other objects of the invention, I have provided improved details of structure, the preferred forms of which are illustrated in the accompanying drawings, wherein:

Fig. 1 is a perspective view of a floor furnace embodying the features of the present invention, parts being broken away to better illustrate the construction.

Fig. 2 is an enlarged fragmentary perspective view of the supporting flange for the outer casing.

Fig. 3 is a horizontal section through the upper portion of the furnace, with the heating unit and one corner of the inner casing being shown in plan.

Fig. 4 is an enlarged horizontal section through one corner of the inner casing, particularly illustrating the liners and flexible mounting thereof.

Fig. 5 is a vertical cross-section through the furnace with the heating unit shown in elevation.

Fig. 6 is a detail perspective view of one upper corner of the inner casing.

Referring more in detail to the drawings:

l designates a floor furnace embodying the features of the present invention and which includes an outer casing 2, an inner casing 3, and a heating unit 4 supported by the outer casing and enclosed in the inner casing.

The outer casing 2 includes substantially rec tangular side and

end walls

5 and 6 formed of sheet metal and having the corners thereof connected together by means of lock seams l, the seams being formed by providing the adjacent edges ofeach sheet with hook-like flanges 8 and 9 interengaged with each other as best illustrated in Fig. 2. While the hook-like flanges are sufficiently close to prevent leakage through the joint, they provide substantial movement of the side and end walls relative to each other so as to reduce buckling of the sheets and metal noises incidental to heating and cooling of the furnace. The seams thus described provide for substantially greater rigidity of the casing in the vertical direction thereof and greatly enhance strength of the casing for a given gage metal. The upper edges of the side and end walls are formed outwardly and laterally vn'th respect to the planes of the sheets, as at l0, and then inwardly, as at H,

toward the plane of the sheets to provide a marginal supporting flange l2 of double thickness of metal l3 and [4.

The ends of the upper ply l3 of the flanges are cut away from the corner seams of the casing as indicated at I5, Fig. 2, and the lower plies M are cut shorter to attach angle-shaped corner plates Hi. The corner plates l6 are of heavier gage metal and have leg portions I1 and I8 bridging the space between the adjacent ends of the upper plies l3 of the flanges and are attached to the under side thereof by spot welding or the like as indicated at I9. The angle members l6 thus cooperate with the lateral flanges to form a substantially rigid rectangular frame aboutthe upper portion of the outer casing to maintain the rectilinear shape thereof and provide a support for the furnace whereby it is suspended within a floor opening as illustrated in Figs. 1 and 5.

The bottom of the outer casing is enclosed by a pan-like member 20 having parallel troughlike air directing portions 2| and 22 extending parallel with the side walls 5 and spaced apart to accommodate a flat surface 23 for supporting the heating unit 4 substantially in the plane of the lower edges of the side an'dend walls as best illustrated in Fig. 5. The supporting portion 23 has an elongated opening 24 extendin parallel with the trough portions 2I-22 to accommodate the burner 25 and provide for inlet of combustion supporting air to the combustion chamber of the heating unit later described.

The burner 25 may be of any approved construction and suitably supported by brackets 26 from the bottom member 20 as illustrated in Fig. 5. The marginal edges of the bottom member are flanged outwardly and upwardly to provide a marginal seat 21 to engage the lower edges of the side and end walls which are preferably bent reversely, as at 23, to cooperate with the marginal flanges 29 of the bottom in maintaining the rectilinear shape of the casing, the flanges 29 being attached to the side and end walls, for example by spot welding or the like.

The trough-like portion 2| is relatively wider than the trough portion 22 and the opening 24 is offset laterally from the longitudinal median line of the bottom member so as to accommodate the combustion chamber 30 of the heating unit 4 and a laterally supported radiator 3| which is spaced from the combustion chamber to form an updraft passageway 32 therebetween.

The combustion chamber and radiator units may be of any approved design but in the illustrated instance the combustion chamber is shown as formed of a pair of mated pan-shaped members 33 having marginal flanges 34 on the vertical and upper edges thereof, which are welded together to form a gas-tight combustion chamber. The bottom of the combustion chamber is in open registry with the opening 24 and has an angle frame 35 arranged with a flange 36 seating upon the supporting portion 23 of the bottom and secured thereto by suitable fastening devices such as screws 31, a suitable gasket 38 being inserted therebetween.

The radiator unit 3 is of similar construction but the lower portion thereof is closed to provide an interior passageway for the hot products of combustion discharged from the upper portion of thecombustion chamber through laterally extending connections 33 as best shown in Fig. 3. After circulation of the hot products of combustion through the radiator chamber they are discharged from the lower portion thereof through a duct 40 extending through a notch 4! in the inner casing and a registering opening 42 in the outer casing to connect, through a draft diverter 43, with a vent pipe 44 leadin to a chimney (not shown). The lower portion of the radiator unit is preferably braced upon the angle frame 35 by means of brackets 45 as best shown in Fig. 5.

The inner casing 3 and its liner constitute the principal feature of the present invention and the casing includes side and

end walls

46 and 41 spaced inwardly from the corresponding walls of the outer casing to form downdraft passages 48 therebetween. The walls of the inner casing are of shorter height than those of the outer casing so that the lower edges thereof are spaced from the bottom member to provide a connection 49 between the lower ends of the downdraft passages and updraft passages 50 surrounding the heatin unit. The upper portions of the side and end walls are flared inwardly to provide a slightly restricted outlet 5| for air moving upwardly around the heating unit and enlarged inlets 52 for the downdraft passages 48.

The walls of the inner casing are also formed of sheet metal and joined together by lock seams 53 similar to the comer seams of the outer casing to provide flexiblity at the corners and at the same time enhance rigidity thereof in the vertical direction of the casing. The inwardly flaring portions of the end walls have flanges 54 overlapping the corresponding portions of the side walls as illustrated in Fig. 6, the flanges being spot welded to cooperate with the lock seams in completing interconnection of the side and end walls.

To prevent overheating of the downdraft passages and insure free continuous flow of cool air into the furnace. the inner casing is provided with a lining 55 that cooperates with the side walls of the inner casing to provide for flow of live air through the passageway 56 therebetween and thereby insulate the inner casing from heat radiated by the heating unit. Since the linings of floor furnaces are located directly facing the hot surfaces of the heating units, and since the walls of the inner casing are supported in a substantially cooler zone and contacted by relatively cool air moving through the downdraft passageways, the liners have uneven expansion and contraction relative to the inner walls of the easing. Consequently much difficulty has been encountered in the construction of floor furnaces because uneven expansion and contraction cause the large flat areas of the inner lining or casing to buckle and cause disagreeable snapping and booming noises when the furnace heats and cools. In order to overcome this difficulty, the lining in the present structure is provided with vertically arranged ribs 51 which also form spacers to maintain a positive spacing between the lining and walls of the inner casing.

In the illustrated instance the ribs 51 have an isosceles trapezoid cross-section and are formed by providing the lining sheets with spaced vertical bends 58 to form slightly converging leg portions 59 for the sides of the ribs and connecting portions '50 forming the bottoms of the ribs, the portions 60 being arranged to lie against the walls of the inner casing and adapted to have slight movement relative thereto. The ribs are secured to the inner casing by connections 6| to allow movement of the lining sheets in a direction parallel with the ribs. These connections may be of any type that will allow independent movement of the lining such as wire stitches, which are illustrated in the drawings,' a wire being formed into staples having leg portions 62 loosely extending through openings 63 in the side walls of the inner casing and through registering openings 64 in the bottoms of the ribs so that the ends may be loosely clinched as at 65. The lining may thus have linear movement on the walls of the inner casing in all directions. Therefore, the body portions or the flat areas of the lining intermediate the ribs maintain their normal plane-like shape and are not buckled because of inability to move with re spect to the inner casing.

In order that the lining on the side and end walls will have relative movement with respect to each other, the lining is formed in sections, for example, one for each side and end wall, with their adjacent edges flanged outwardly, as at 56 and 61, and spaced apart, as at 68. When thus spaced the sections expand freely without interference as would be the case if the corners were connected.

While the ribs in the lining eliminate disagreeable metal noises usually encountered in floor furnace construction, they also have the function of l providing greater surface area for absorbing radiant heat and ive greater contact of the circulated air, thereby increasing efficiency and at the same time permitting the furnace to operate at lower working temperatures.

In order to further increase the heating area contacted by the upwardly moving air stream, the space 32 between the combustion chamber and radiator is divided by a heat converter 69 comprising a sheet metal plate having a series of vertically arranged corrugations or ribs '10. The plate is retained in proper position by arms II that are welded to the flange seams of the combustion chamber. The diverted plate .absorbs radiant heat from both the combustion chamber and radiator unit and passes the heat units into the flowing air moving upwardly therebetween. The diverter plate thus reduces heat loss through the chimney and results in lower fuel; cost. The open top of the outer casing is closed by the customary floor grill l2. j

The inner casing is floatingly suspended within the outer casing by means of studs 13 extending laterally from the end walls near the upper portions thereof and which are supported within notches N of inwardly extending brackets attached to the inner face of the end walls of the outer casing. The notches," opening upwardly, permit removal of the inner casing through the open top of the outer casing upon removal of the grill. This floating suspension of the inner cascasings provide for sufficient flexibility to avoid noises that are usuallyproduced in the inner and outer casings of a floor furnace.

What I claim and desire to secure by Letters Patent is:

1. In a floor furnace, an inner casing comprising, sheet metal end and side walls, individual liner sections for said walls having the adjacent side edges of adjacent liner sections unconnected and completely spaced from said casing and from each other to permit independent movement of the liner sections relative to each other responsive to uneven expansion and contraction of the liner sections with respect to said walls of the trimer casing when the floor furnace is in opera- 2. In a floor furnace, an inner casing comprising, sheet metal end and side walls, liner sections for said end and side walls having adjacent side edges spaced apart to permit independent movement of the sections relative to each other responsive to uneven expansion and contraction of the liner sections with respect to said walls of the casing, and means loosely supporting said sections on the respective side walls of the easing for relative movement of the sections in directions parallel with said spaces between the liner sections to compensate for uneven expansion and contraction of said liner sections with re- 01' spect to the casing walls without buckling of the "liner sections between the points of support on ing within the outer casing provides independent movement between the respective casings so as to avoid any stresses tending to cause snapping and booming noises of the sheets composing the side walls thereof.

In operation the hot gases moving into contact with the interior of the combustion chamber and radiator 3i heat the surfaces thereof, which heat is picked up by the air surrounding the heating unit 5, causing a rise of temperature within the inner casing 3 so that the colder, heavier air in the downdraft passages E1 causes upward displacement of the heated air through the central portion of the grill, thereby setting up circulation from the room downwardly through the marginal edges of the grill, through the downdraft passageways 48 for deflection upwardly by the trough-like portions 2! and 22 into the updraft passageways surrounding the heating unit. That portion of the heat which is radiated from the hot surfaces of the heating unit is absorbed by the lining so that it is picked up by the air moving in contact with the respective sides of the lining. The portion of the air which moves upwardly through the spaces between the liner and the walls of the inner casing carries away the heat of the liner with sufficient rapidity to avoid heating of the air in the downdraft passages 38. The heat converter 69 also absorbs radiant heat which is taken up by the air moving thereover so that the heat loss through the chimney is reduced to a minimum.

As the lining is carried at a higher temperature than the walls of the inner casing, it has uneven expansion and contraction with respect thereto, upon heating and cooling of the furnace, however, the laterally flexible ribs and the loose support thereof on the inner casing provide for sufficient movement of the flat plane portions to avoid buckling which causes the usual booming and snapping noises. The spaced edges of the individual liner members provide for free movement of one liner with respect to the adjacent liner. The lock, corners of the inner and outer the casing.

3. In a floor furnace, an inner casing comprising, sheet metal end and side walls, liner sections for said end and side walls having adjacent side edges spaced apart to permit independent movement of the sections relative to each other responsive to uneven expansion and contraction of the liner sections with respect to said walls of the casing, and means loosely su porting said sections on the respective side walls of the easing for relative movement of the sections in directions parallel with said spaces between the liner sections to compensate for uneven expansion and contraction of said liner sections with respect to the casing walls without buckling of the liner sections between the points of support on the casing, said liner sections having transversely flexible ribs to compensatefor uneven expansion when the liner sections move to and from each other.

4. In a floor furnace, an inner casing assembly including interconnected side and end walls, a liner section for each of said walls having transversely flexible ribs spacing the major portions of said lining from the walls of the casing to compensate for uneven expansion of the lining with respect to the casing in directions transversely of said ribs, said liner sections having adjacent side edges spaced apart, and means loosely connecting the ribs with the casing to support said lining for limited movement to compensate for uneven expansion and contraction of the lining in a. direction longitudinally of said ribs.

5. In a floor furnace, an inner casing assembly including side and end walls connected by lock seams to form flexible corners for said casing, separate liners for the side and end walls of the casing having spaced transversely flexible ribs spacing the major portions of said liners from the casing, and means loosely connecting the ribs with the walls of the casing to support said lining within the casing, said liners being spaced apart adjacent said lock seams.

6. In a floor furnace, an outer casing, an inner casing, means suspending the inner casing for support within the outer casing with walls of the inner casing spaced from corresponding walls of the outer casing, a. liner for the inner casings including a plurality of flexible sections unattached with respect to each other and having adjacent side edges spaced apart and out of contact with each other and the inner casing and with the side edge of one section located in a different plane than the adjacent side edge of the next adjacent section.

'7. In a floor furnace, an outer rectangular casing, an inner correspondingly shaped casing supported within the outer casing with walls of the inner casing spaced from corresponding walls of the outer casing to provide downdraft passages therebetween, a, heating unit in the inner casing, a liner section for each wall of the inner casing and having ribs extending parallel with the downdraft passages to space body portions of the sections from said walls of the inner casing and to form passageways for insulating the downdraft passages from excessive heating by said heating unit, and means supporting the liner on said inner casing, said sections having adjacent vertical side edges slightly spaced apart to permit expansion of the sections.

8. In a floor furnace, an outer casing, an inner casing, means suspending the inner casing for floating support within the outer casing and with walls of the inner casing spaced from corresponding walls of the outer casing to provide downdraft passages therebetween, a heating unit in the inner casing, a liner between the inner casing and the heating unit and having ribs extending substanthe adjacent side edge of an adjacent section to permit expansion of the sections.

v 9. In a floor furnace, an outer casing, an inner casing supported within the outer casing with walls of the inner casing spaced from corresponding walls of the outer casing to Provide downdraft passages therebetween, a heating unit in the inner casing, a liner between the inner casing and the heating unit and having ribs extending parallel with the downdraftpassages to space bodyportions of the liner from said inner casing and to form passageways for insulating the downdraft passages from excessive heating by said heating unit, and fasteners extending relatively loosely through the inner casing and said ribs for supporting the liner on said inner casing for limited independent movement thereon responsive to expansion and contraction incidental to heating and cooling of the furnace, said liner being composed of a plurality of sections slightly spaced apart with the edges of adjacent sections located in different tiall parallel with the downdraft passages to space body portions of the liner from said inner casing and to form passageways for insulating the downdraft passages from excessive heating by said heating unit, and means supporting the liner on said inner casing, said liner being composed of a plurality of sections having adjacent side edges slightly spaced apart with the side edge of one adjacent section in a different plane than planes to permit expansion of the sections.

10. In a floor furnace, an outer casing, an inner casing supported within the outer casing with walls of the inner casing spaced from corresponding walls of the outer casing to provide downdraft passages therebetween, a heating unit in the inner casing, a liner between the inner casing and the heating unit and having transversely flexible ribs extending parallel with the downdraft passages to space body portions of the liner from said inner casing and to form passageways for insulating the downdraft passages from excessive heating by said heating unit, and means loosely supporting the liner on said inner casing for independent movement thereon and cooperating with said ribs to avoid buckling of said lining and inner casing responsive to expansion and contraction incidental to heating and cooling of the furnace, said liner being composed of a plurality of sections slightly spaced apartwith the edges of adjacent sections located'iin-diflerent planes to permit expension of thesections one relatively to the other.

AIHBROSE DEAN OLDS.