US982303A - Fire door and shutter. - Google Patents

Description

P. L. SAINO, D. M. LYNCH, W. P. DUNBAR & J. H. WEATHERFORD.

FIRE DOOR AND SHUTTER.

APPLICATION FILED FEB. 11, 1907.

Patented Jan. 24, 1911.

4 SHBETSSHEET 1.

0 o o o c 00 9 I 1 9 X f F. L. SAINO, D. M. LYNCH, W. F. DUNBAR & J. H. WEATHERFORD.

FIRE DOOR AND SHUTTER.

APPLIOATION FILED FEB 11, 1907.

Patented J an. 24-, 1911.

4 BBBETEPBHEET 2. v

F. L/SAINO, D. M. LYNGH, W. P. DUNBAR & J. H. WEATHERFORD.

' PIREDOOR AND SHUTTER.

APPLICATION FILED FEB. 11, 190..

Patented Jan. 24, 1911.

4 SHEETS-SHEET 3.

%Z/I/EJJEJ. l/vrf/vra/r n M w 7 F. L. SAINO, D. M. LYNCH, W. F. DUNBAR & J. H. WBATHERPORD.

FIRE DOOR AND SHUTTER.

APPLICATION FILED FEB.11, 1901.

Patented .1111124, 1911.

4 SHEETSSHEET 4..

. N n. 1 1. 1 i d uNrrE STATES PATENT QFFlQE.

'ELIX L. SAINO, DOSSEY M; LYNCH, WILLIAM F. DUNEAE, Ann JOSEPH I-I. WEATHER- EoEn, 0F MEMPHIS, TENNESSEE, ASSIGNORS T0 SAINO FIRE noon AND SHUTTER COMPANY, or MEMPHIS, TENNESSEE, A CQRPORATION or TENNESSEE.

- FIRE DOOR ANl) SHUTTER.

To all whom it may concern:

Be it known that we, FELIX L.. SAI o, DossEY- M. LYNCH, VVILLIAM F. DUNEAR, and JOSEPH H. l/VEATHEREORD, citizens of theUnited States, residing at Memphis, Shelby county State of Tennessee, have invented certain-new and useful Improvements in F irellpors and Shutters,- of which,

the followingis a s ecification.

Our invention re ates to certain new and useful improvements in fire doors and shut ters, and has especial reference to improve;

ments in those which are made of sheet metal.

The objects of our invention are to so improve the construction ofthe door or.

shutter; first ;that it will withstand a severe amount of heat without disintegrat ing; second; that it will not'warp or twist out of shape under severe test; third; that 1t Wlll transmit a minimum amount of heat;

fourth; to improve generally the construction and details! We accomplish these objects as will be more fully set forth hereinafter in the drawings, specification. and claims, in which, however, we have confined ourselves to the construction of the door, and omitted allreference to the shutter.

In the drawings -F igure 1 is a face view of the door showing as it appears when closed, and showing the hangers, stay-roller andbinders which hold it in place, as they Fig. 1.

are used ordinarily. Fig. 2 is a partial back elevation and section on the line IIII Figs. 3 and 7', looking in the direction of the arrow. This and the remaining drawings are on a very much larger scale than that of 3 1s a sectional elevation on the.

Fi' I line III-ill of Fig. 2 looking from the right toward the left of F ig. 2. Fig. l is a section on the line IV--lV of Figs. 5 and (3 looking .down. Fig. is a sectional elevation on the line VV of Figs. 4i and 6 looking in the direction of the arrows. Fig. 6 is a partial front elevation showing the upper left hand corner of the door shown in Fig. 1. F ig. "T is a section of the door on the line VIl-Vll of Fig. 1 looking down. 8 is a section on the line VHF-VIII of Fig. l looltin in the direction of the arrow. Fig. 9 iragznentary'section on the line IX--lXof Big. 10 looking down. Fig. 10 is on the line X-X of Fig. 1 looking in 5 irection of the arrow.

Specification of Letters Patent. Patented Jan, 24, 191 Application filed February 11, 1907. Serial No. 356, 891.

Referring nowto the drawings in which like parts are designated by'the same nupeculiar construction.

the door. disposed Figs. 6 and 7. The several widths are rivof a single rigid sheet.

in the present door, of four sections 3&3",

3, etc, which, i f corrugated, preferably havetheir corrugations horizontally disposed.

one overiapping'the upper edge of the next, and coupledv loosely together by the loose rivets 4, which are put through the-vertical slots 5 in the overlap; orother eflective mechanical device which holds these edges in alinement,lmt' which permits the overlap to. be diminished by a sliding motion. Thus a vertically expansible rear wall is formed. In Figs. 2 and 3 it will be seen that one or two of the corru gations are flattened to permit easy sliding of the overlap when corrugated sheets are used. i

The rear portion of the door'on the side away from the fire is composed of the refractory. sheet 2 of asbestos or similar material, attached to the inner surface of the" metal sections 3 3, 'etc., by means of rivets 3 and large washers 7, or by other ef material to the rear sheet 3 and. in contact therewith at intervals throughout its surface.

sheets 2 and 3, are riveted together by rivets S and f) at the four edges oi the door only.- .atswill be seen by reference to Figs. 6, 7, S and 10 the rivets 8 at the top and bottom edges are provided with spacing collars or washers 10, which serve to hold the front -1 morale in all views, the door consists funda-flmentallyf a front 1 of sheet metal, an inmade of one or more 1 of sheet metal ofcommer vertical, as will be more clearlyseen by'reference to eted-rigidly together to form the equivalent The metal portion 3' ofthe rear is com 1 posed of two or more sections of sheet metal;

As will be seen by referenceto Figs. 2 and 3 they. areplaced with the lower edge of the" We may use $01116 fcctive means of riveting the more fragile;

The front 1 and the rear, composed of 60* ported and stifiened by rigidly apart to form an air chamber orchannel extending throughout the surface of the door, By reference to Figs. 6 and 8 it will be seen that the top of the channel .is made to open u ward and outward toward the fire side 0 the door by making the front sheet shorter than the rear at the top. Likewise Fig. 10 shows the rear wall shorter than the front at the bottom of the door, thus allowing the free entrance of air from the rear or cooler side of the door, as shown by the bent arrows. When a high temperature is maintained outside the front sheet, heating said sheet to a red color, the air in this channel or chamber becomes heated by intimate contact therewith, and, since the air in the room to be protected is at a much lower temperature than that on the inte rior of the door, a flue-action or draft will be caused by the continuous displacement of the lighter heated air by the cooler. This fresh supply of cooler air, by absorbing heat from'the front sheet during its ascent, allows an increase in the duration and temperature of the exposure to which the door may be subjected without melting the metal. I

When corrugated metal, horizontally disposed, is used for sections of the'rear metal sheet 3, 3 3 etc., a series of dead air pockets or channels are formed between the door. This also provides corrugations of said sections and the sheet of refractory material 2, thus reducing to a minimum the radiation of heat through the a transverse stiffness throughout the rear surface of the door.

The stiffening frame is formed of stiles or side framing consisting-of channels 12 and bars 11 and 14 (observe Figs. 4, 5 and 7); of top rail, consisting of channel 31 (observe Fig. 8) and of bottom rail, angle 32 (observe Fig. 10). These are riveted or or otherwise rigidly fastened each is composed of expansively connected sections or parts that the door as a whole may expand in all directions. Inharrow doors'it is commercially desirable to omit the sectional formation of-the top and bottom rails, since the Warping and twisting of relatively shortchannels and angles is inconsiderable even when subjected to severe difference in temperature between the side edges of the same piece of metal.

Portions of the side framing are'protected from severe heat at the side edges of the door by the overlapping of the side edges of the front metal sheet 1 and the sheet sf refractory material interposed, as, will be seen by Fig. 77 If theffront sheet b'e corrugated, it is flattened at the side edges for this purpose, anda portion of the flattened marginal ,e'tlgeis bent backward at right angles to fer-m an L in cross section which extends as far'backas the rear wall of the stiffening framerqThe sheet of'refractory material2"is.bent to conform to the inner surface of this L, and the edges of both sheets l and 2 are retained by rivets 18, as may be seen by reference to Fig. 4. Be tween the sheet of refractory material 2 and 'the remaining portion of the aforesaid flattened marginal edge of the front sheet 1,

close in the corner of the l. and fiatwise to fractory sheet 2 andmetal-sections 3, 3 3,

' etc. Being flat against the hot metal sheet at its front and at one edge. and against'the asbestos. sheet in the rear, and having oily one narrow edge as a cooling surface, his bar attains almost the same temperature as thefront sheet and, therefore, expands and contracts with it without tearing the rivet holes of rivets 9.

'The stiifening channels 12 are formed by.

bendin a narrow piece of sheet metal longitudinal ly to form a square cornered U in cross-section with one leg longer than the other. The extra length of this longer leg is then turned outward as indicated b in Fig/ L In assembling, these channe s are inverted and placed with the portion 12 between the side edges of the rear metal sections 3*, '3", 3, etc., and the asbestossheet 2, the shorter side coming against 'the inner surface of the L of the asbestos sheet. These channels 12, being narrower across the U than the width of the. flat straps 1i,

permit the same rivets 9 which pass through the front sheet 1 and bars ll, to pass through the leg 12 of channel 12, and through the side edges of the rear sections 3*, 3*, 3", etc;

which are superposed. Thus a vertical box-- like air passage or flue of considerable dimensions is formed by the channel 12 and asbestos sheet 2, the metal walls of which are shielded from severe heat by the asbestos and the fire-proof wall against which the door placed in service. Since this stiti'ening channel is protected and is, therefore, practically cold, there will be a consider-- able dilference between its length and the length of the fiat strap 11 to which it is riveted by rivets 9, when the door is subjected to heat on. the exposed side. To pre which are long enough to overlap a considrrable distaiicc.

It will be noted that there arejtour sections also, 3, 3, 3", etc, in the rear metal sheet 3-5 of this particular door; and that they are loosely coupled together at bottom and top edges respectively. Thus there are as many overlapping or telescopingsections in channel 12 asthcre are sections 3, 3, 3, etc., of the rear metal sheet 3.

"Special attention is now called to the manner of riveting together these several pieces. The rivets 9 pass completely through the front metal sheet 1, metal strap 11, asbestos sheet 2, portion of channel 12 and edge of a section of rear metal sheet '3 and binds all of them rigidly together at the .points of riveting. But by close inspection of Figs. Nos. 1 and 2 it will be seen that the spacing of rivets 9 is notuniform, but that they are placed in segregated groups; each of which. is made. up of a few uniformly spaced rivets. Theoretically, these metal sections of rear sheet 3 and channels 12 should be riveted to the front sheet 1 and strap 11 at one part only with a single rivet at the middle of the side edge of each section; but in practice it is found that the extent of riveting employed does not so greatly interfere with the unequal expansion and contraction of the several parts that the .va'i -ping of the door as a whole, and the tearing of the rivet holes and the rivets, are observed. The number of rivets employed ,materially increases the strength of the whole structure when distributed as do scribed. Thus it is seen that the vertical rear metal wall 3; and consequently the bulging away from thewall 'at the middle of thesides of the door will not occur as with rigid stiffening members of one piece,

' channel (obs riye Figs. 4, 5 and 7.l

or of several pieces so constructed as to he the expansive equivalent. of a single piece.

.l.he'channels 12 are stiffened and held in ,alinemcnt by placing a stiff bar of metal 14,

which extends ,the full length of the door, within the channel and retaining it against vthev back, or ,the bottom of the U, by the insertion of ;several bolts 13 throu 'h the 13 pass across in, front of bar 14 and hold ,it closely in place but do not prevent the wertical sliding of the several sections of channel 12 along thebar. Bolts 13 are so inserted at the? overlap orKf telescope. of the joints, and at bther points nearby,.that.they

prevent both thebendingof the barv and the buckling of the, overlapping joints in the channel, but allow the. individual expansion:

Bolts" of each section, and their separation from each other. As before mentioned they also pass through the L shaped edges of the front sheet 1 and refractory sheet 2, and fulfil the additional service of retaining them against'the stiffening frame and preventing the buckling and twisting of the thin edge as angle iron usually does under unequal heating of the edges. Theholes for these bolts 13 are slotted longitudinally in the outer metal sheet 1 and refractory sheet 2 and in the overlapping portion of an adjacent channel section. Bar 14: may be bent at its upper end as shown at 15 in Fig. 5 and abut against bar 11 to give the corners rigidity and to allow a fastening such as a wrapping of a portion of upper channel 31, or other means resorted to for securing it at one point in its length.

* By referring to Fig. 8 it will'be seen that the upper edge of the rear metal section 3 extends above the front sheet 1 and asbestos" sheet 2 and is bent outward toward the front of the door, and then a portion 'ofthis edge doubled back, thus forming the doubled-back portion 35,. and riveted or bolted at its loweredge to the front and back walls of the door by the rivets 8 pass ing completely through all parts of the door at the top. This channel rail 31 may be made'in' sections and be reinforced an aliningstrip as used'with the side channels 12 or not, as the width of the door opening requires. The upper edge of this channel 31, being exposed to the heat, may attain a higher temperature than the lower edge, and therefore provision must be made in doors of unusual width. for thcwa'rping or distortion produced by a great incqu'.-1lit v of temperatures of the opposite edges of the same channel. However, the heat largely deflected away from this exposed surface by the deflected upward current of air before mentioned, and by the. proximity of the track 17. i

The lower rail or angle 32 of the stiffening frame is shown in Fig. 10. As here shown, it is an angle with vertical leg riveted to the lower edge of she'et fliI a rnl-witli "the other leg extending horizontallybackward tothe rear face of the-dryer. "By refrence to Fig. 1 1t will beseen that this angle 1s formed 1n sectlons wh ch by overlapping and telescoping freely;,a;llow individual. ex-

pansion and contraction,ofqthe several sections; These sections-as in thechannelj-ll -may have a trotighor c h'annel formed at the rear edge for the rec eption-of a. stiffening bar in. a mariner sim lar to theifstiffening bars 14 in the side channels 12. This part of the frame, the angle 32, has a very small portionexposed directly to the action of the flames as it rests directly upon the sill of brick or concrete 23, and is thereby protected fromthe heat from below; therefore the sectional format-ion is employed in wide doors only.

By reference to Figs. 1 and 8 it will be seen that the door is supported in the usual manner by the hangers 16 which are of the I usual form, and therefore not specially described. These hangers run on a flat track 17, fastened to the wall 18 by bolts 19and spacing cones or brackets 20 in the usual manner.

21 is a metal bar fastened to the inner sideof the hanger 16, having the arm 22 to the wall by means of the track.

25 is the ordinary form of stay-roller, and 26 the stay-roll strip which is fastened to the face. of the door, and formed with a wedge 26 as shown. in the plan Fig. 9, in order that the door may be jammed closely to the wall when the momentum of the door in closing jams this wedge behind the stayroller 25. p

In: Fig. '1, the ordinary form of front binders are shown at 27 27 28 of Figs. 1 and 7 isa rear binder hoop which consists of a hook-shaped piece of metal, the back of which is countersunk in the! wall 18' andfastened -to' the same by the bolts 29. This binder hook is adapted to engage an opening 30 through the boxshaped side of the stiffening frame and. holds the door when shut firmly against the.

wall.

33 is a spacer bar or washer of metalbetween the front and back at the pointwhere the hanger bolts 34 pass through the door to prevent drawing of the front and back together at that point (observe Fig. 8).

The door is so hung that under ordinary circumstances'the flame will come against the front sheet 1 or face of the door.

the sections of the cooler back and those between thc. cooler section of channel 12. But, being fastened at the side edges to the ends of'the sections 3 3, etc., which are cooler and, therefore, expand much less than sheet 1, the front sheet buckles and bulges outward to compensate for the difference ,in horizontal expansion, tending to become'a longidudinal section of a large corrugated cylindrical surface. This bulging, however,

j spacers 10.

This sheet when heated expands in a vertical di rection rapidly, stretching the joints between is restricted at the top and bottom of the door by the rails 31 and 32 of the stiffening frame which are riveted by rivets 8 to the bottom of each corrugation, the expansion of sheet lbeing used up by the collapsing accordion-motion of the corrugations of the red-hot metal sheet 1. The middle portion, however, not having this restraint does bulge outwardly, the two hulgings, horizontal and vertical, producing a bellying outward or a spherical bulging at the center of sheet 1. By this distortion a larger air space is formed between the front and back, and asuction of air is produced, which air when heated passes out at the top, and sets in motion the cooling current before mentioned.

It will be observed that the" cool air is drawn from the side of the door away from the fire, entering the door at the bottom, and is discharged as heated airat the top of the door on the fire side only.

The refactory material, drasbestos 2, being held intact by its fasteningsto the rear sheet 3, is comparatively undisturbed by changes in temperature of the face of the door, and serves to prevent kany considerable amount of heat being radiatedthrough the door.

It will be noted that the rear section 3, 3", etc., could be fastened horizontally across its middle to the front sheet in a manner and bottom similar to that usedat the top e. by use of rivets 8- and of the door, '5.

As will be noted the door shown in drawings is formed of sheets of corrugated metal disposed with the corrugations, at right angles to each other. It will be readily seen, that the sheets of which the door iscomposed may be simply flat sheets of metal which, provided they are spacedapart-at the top and bottom, and are properly put'together to permit the vertical separation of the-rear sections, and bulging of the front sheet at the center, will accomplish practically everything that the corrugated sheets do. The corrugated sheets make a stiffer and better door, and for that reason should be preferred in ordinary practice. While-,we have confined our description to a door, it .will be readily seen that by substituting the word shutter for door ,this description will apply to a shutter as'well."

Having fully described our invention, what we claim and desire tosecure-by Letters Patent in the United States is "'1. In a device of the kind described, the combination with a front wall of sheet metal,

and a c ompbsite back wall of non-combustible materials divided into separate overla ping sections, and means for spacing t ewalls apart to form an air channel; of means for connecting the sections together whereby a sliding movement of the overlap is al 1 lowed transversely to the edges to compenll l ' material and being divided into independent their edges.

. of said form an air space;'the stantially in a single piece, the back wall besaid sectionsgbeing composed of sheet metal wall, a stiffening .lapping sections, [posed of sheet metal and refractory mate- .rial fastened together, means for holding the front and back walls apart to form an air tion withja front wall, and a back wall dies'aeos sate for the unequal expansion of the front and back walls. I I

2. In a fire door or shutter or the like, consisting of two parallel walls spaced apart to front wall being subing composed of sheet metal and refractory overlapping sections with-means for rigidly .attaclnnga portion-of each section to the expansile other portionsof the sec- 3. A fire door. or shutter having a front wall, a back wall of overlapping sections,

and sheet refractor material fastened together, means for olding said front and back walls apart to form air space, and means for-rigidly fastening said sectionsto the front wall throughout only a portion of 4. A fire door or shutter having a front frame, a back wallof over said sections being comspace, and means for independently fastening each section to the frame whereby a .diffcrence betweenjtheexpansions of the section and frame is "allowed. I

5. In a fire door or shutter, the combinaided into sections whoseedges overlap, of means for connecting the overlapping edges sections together permitting cxpanl s1 re movement transversely to the adjoining edges of the section's.

. 6..In a fire door 01' shutter, the combination with a front wall substantially in one piece, and a back wall of metal composed of a plurality of overlapping sections,of a plurality of loose rivets inserted through slotted 1 holes in the overlap ing edges to'expansibly l and means for fasten fastenings distributed throughout only a or.-

connect together an aline the said. sections, ing the said walls to- I gelher.

7. In a' fire door 01' shutter, the combination with a front wall substantially in one I piece, of a back wall of sheet metal compris-- i ing a plurality of separate sections, and a a plurality of fastenings distributed throughi out only a portion of the surface ofeach sec- I tion for rigidly front wall while allowing sliding motions of other portions of the sections with respect to the adjacent portions of the front wall to compensate for a diiference in expansion.

8. In a fire door or shutter, the combination with a frame, a front wall attached thereto, and a back wall composed of a plu-' rality of separate sections, of a pluralityof tion of the surface ofeach section for' rigidly,

section :and the main securing that portion to the securing that portion to the frame while allowing sliding-motions of other portions of the section with respect-to'the adjacent portions of the frame to compensate for a difference in expansion.

9. In a fire door or shutter, the combina tion with a stiffening frame, a front wall attached thereto, a back wall comprising a plurality of separate sections, spacing said walls apart to form an" air space, of a plurality of fastenin s distributed throughout only a portion 0 each section for rigidly securing that portion to the and means for frame while allowing sliding motions of otherv portions of the section withrespect to the adjacent portions of the frame to compensate for a difference in expansion. I 10. In a fire door or shutter, the combination with the body portion of sheet metal and refractory material, and metallic stiffening members attached thereto, the edges of the refractory material overlapping on the memher to protect the said stifi'ening members from severe heat.

1 1. In a fire door or shutter, the combine tion with a main body portion of sheet metal and refractory of sections attached independegtly"thereto, said sections being protected from severe heat by portions of the sheet metal and refractory material.

12. In a fire door or shutter, the combinetion with a non-combustible'main body portion, of metallic stiffening-members composed of a-iplurality of sections attached thereto, means for stiflenin the said sections, means Io fastening each of said member of the main body portion whereby a diflerenceb'etween the expansions of the body portion is allowed; said stiffening members being insu lated from the heat of the common member by an interposed layer of refractory material.

13. In a fire door or shutter the combination with the body part thereof, and stiffening members composed of a plurality of sections of metal attached thereto; of a stiff bar slidably secured in commpn to the sevr individually material, of metallic stiffening members composed of a plurality into alinement.

sections to a common eral sections of a member for stiffeninginto means for fastening each of'thejsaid secscctions and for reintions tora corresponding sectionof the back wall whereby a difference between the expansionsof the section of back wall and: sec tion 10f. stiffening member is allowed; said heat of the front wall by 1 opening therein stifi'ening'members being insulated from the an interposed layer of refractory material.

15. The combination ofa fireproof wall having a door opening therein, and a rear binder hook attached to said wall, w'1th a door consisting of metal sheets, a stifi'emng frame for sald door projecting backward from said sheets, the said frame having an adapted to be engaged by the said hook.

' 16. A fire door or shutter, having a tele 'jscopically expansible stiffening frame built into and forming a component part of the main body ortion thereof. 17. In a re door or shutter, the combination with a main body portion, of a stifi'ening member divided into sections, and means for stiflening into alinement the several sections of a member.

18. In a non combustible fire door or j-shutter, the combination with a main body portion, of stiffening members attached thereto composed of a plurality of sections overlapping at adjoining and freely sliding ends; said sections being alined by their in ,portion, of stiffening members attached thereto composed of a plurality of sections lapping at adjoining and freely sliding ends; said sections being alined by their independent fastenings to a common member of the main body portion, and by projecting fastenings of one inserted through slots in the lapping portion of the other.

In a non-combustible fire door or shutter, the combination with a main body portion, of stiffening members attached thereto composed of a plurality of sections with adjoining ends free to slide; said sections being alined by their independent fastenings to the said main body portion and by a stifi} ening barslidably secured in common to the said sections.

In a noncombustible fire door or shutter,the combination with a main body por tion,,of stiffening members attached thereto composed of a plurality of sectionseach of hollow.- substantially U shaped cross sectionv overlapping a'tiadjoining and freely sliding ends; said 'sectionsjbeing alined by the over:v

partially inclosing the comple-,

lap ofhone mentary form of the other, and by projecting fastenings of oneinserted through slots in theoverlapping portion of the other.

w 22.1 131 a non-combustible fire'door or shutlet; the combination with a main body portion, of stiffening members attached thereto composed of a plurality of sections each partially inclosing the comof hollow substantially U shaped cross section overlapping at adjoining and freely sliding ends; said sections being al ned by the overlap of one partially inclosing the complementary form of the other, and by a stiffening bar slidably secured in common to the'said sections.

23. In a non-combustible fire door or shutrality of overlapping sections attached there to, of a plurality of projecting fastenings of one section inserted through longitudinally slotted holes in the overlapping portion of the other section to connect each section expansibly to the adjoining section.

24. In a non-combustible fire door or shutter, the combination with a main body portion, stifiening members composed of a plurality of sections attached thereto, and means for alining and stiffening said sections, of means for fastening each of said sections to a common member of the main body portion whereby a difference between the expansions of the section and the main body portion is allowed.

25. In a non-combustible fire door or shutter, the combination with a main body. portion, stiffening members composed of a plurality of sections attached thereto, and means for alining and stifiening'said sections, of a plurality of fastenin'gs-distributed throughout only a portion of the edge of each section for rigidly securing that portion to the main body portion while allowing sliding motions of other portions of the section with respect to the adjacent portions of the main body portion to compensate for a difference in expansion.

26. In a fire door or shutter, the combination with front and back walls of non-combustible materials, of metallic stiffening members composed ofa plurality of sections attached thereto, and means for' alining and stifiening said sections, .of -means for fastening each section to a corresponding section of the back wall whereby a difference between the expansions of the section of back wall and the section of stiffening memher is allowed.

j 27. .In a fire door or shutter, the combination with front and back walls, stifi'ening members composed of a plurality of sections attached thereto, and means for alining and stiffening said sections; of a plurality of fastenings distributed throughout only a portion of theedg'e of each section for ri idly securing that portion to :1. corresponding portion of a section of the back wall while allowing sliding motions of other portions of the section of stifiening member with respect to the adjacent portions of the section of back wall to compensate for a difference in expansions.

28. In a non-combustible fire door or shutnames to this specification, in the presence ter, the combination Withe main body porof-two subscribing Witnesses.

tion, stiffening members composed of a plu-' FELIX L SAINO rality of hollow sections in alinement at- DOSSEY LYNCH 5 cached thereto, of splurality of fastenings I ,ILLIAM DUNE to confine a stlfi'ening metal bar Within the v w 1 7 several hollow sections in c ommony which JObLPH EATHERFORD' v are thereby slidably secured to the .said \Vitnesses:

metal bar andstifiened into alinement. F. M; FLANERY, 10 In testimony whereof we have signed our H. H. HIGBEE.

Images