US2416284A

US2416284A - Fire-vent building

Info

Publication number: US2416284A
Application number: US633216A
Authority: US
Inventors: Arthur L Brown
Original assignee: Factory Mutual Research Corp
Current assignee: Factory Mutual Research Corp
Priority date: 1945-12-06
Filing date: 1945-12-06
Publication date: 1947-02-25
Anticipated expiration: 1964-02-25

Description

Feb. 25, 1947. WN 2,416,284

FIRE-VENT BUILDING Filed Dec. 6, 1945 flnzkurgp'rawm Patented Feb. 25, 1947 UNITED STATES PATENT QFFICE I FIRE-VENT BUILDING Arthur L. Brown, Boston, Mass assignqr to Factory Mutual Research Corporation, I Boston, Mass.,'a corporation of'Massaen setts Application December 6, 1945, Serial No. 633316 8 Claims. ((31. r0871 The spread of fire in building is often caused by the heatwhieh rises from 1a localized fire striking a-ceiling or a roof and then spreading laterally. It has been proposed to have automatic ventilators in aroof to open in response to a fire, permitting the escape of the heat through an opening in the roof and thereby delaying the spread ofthe fire. However these-automatic ventilators have not been satisfactory for various reasons. They require fusible links and other mechanism which is more or less in the way and which tends .toget out of order. Moreover the ventilators frequently stick owing to the fact that they need tobe opened only at rare intervals.

Objectsefthe present invention are to provide a construction 'which not only provides a vent pe ng ut ma ca ly i re o e to a fire but which requires no fusible links or other mechanism, whichcan not fail to function due to sticking, which can easilybe made weatherproof with notendency to resultin aleakyroof, which tends to localize a fire more effectively than do the automatic ventilators :of the prior art, and which minimizeswatertdamag inbuildings where auto matic sprinklers have been installed.

According to the present invention the roof is provided with supporting members of any usual or suitable construction but the covering material has at least a portion of thin fusible sheet material exposed on both sides so that the rising column of heat form a localized fire beneath the roof can quickly form a vent opening to permit the escape of the heat, thereby retarding the spread of the fire, and to allow a rapid removal of smoke, thus facilitating manual firefighting. While the fusible material preferably comprises one or more panels of fusible metal, such as alloys of zinc and tin or alloys of cadmium, zinc, lead and bismuth, it may comprise plastic material which has a low melting point, such as Pliofilm or other rubber composition, natural resins, alkyl resins and asphalts, or which has a low kindling point and is rapidly combustible, such as pyroxylin. Indeed the panels may be translucent so that they also serve to admit light. While the fusing or ignition temperature of the sheet material may be varied to suit difierent conditions, in most cases the temperature should be 300 F. or lower and in no case should it exceed 700 F. By having the temperature at or below that at which the sprinklers open, widespread water damage is avoided. When an insulating efiect is desired two or more sheets of the fusible material two adjacent sheets so that each sheet is exposed on both sides. In the preferred embodimentfusible sections are disposed .at recurrent intervals throu h thexarea of the roofand metal fire cure.

tains depend from the roof between the sections to assist in directing the heat tothe fusible sec-r: tion immediately above the fire.

For the purposeof illustration typicalembodis ments of the invention areshown in the accomx-i panying drawings in which.

Fig. 1 is a perspective view of the invention applied; to. one. type of building;

supported on longitudinal purlins a, 9 and-10;

The space between thetwo sides of the central roof may be bridged-by -an arched strip =I--l securedin place-byfasteners 42'. At recurrent tervals along the roof fire curtains I3 hang down approximately to the bottom of the central section 5.

The modification shown in Fig. 3 is similar to that shown in Figs. 1 and 2 except in that the building M has a flat roof and instead of the entire roof being covered with fusible sheet material the roof is provided with recurrent openings covered with panels I5 of the fusible sheet material. Each panel may be sealed directly to the roof around its periphery or it may be mounted in a steel frame which in turn is mounted over the edge of the opening in the roof. Fire curtains may be provided not only transversely of the building between each two adjacent transverse rows of panels but also longitudinally of the building between each two adjacent longitudinal rows of panels.

From the foregoing it will be understood that in the case of a localized fire the heat will rise to the fusible sheet material immediately above the fire and there form an opening in the roof through which the heat can escape so that the roof will not cause it to spread out to adjacent sections of the building. The modification shown in Fig. 3 has the advantage that. when a. panel is destroyed the roof may be restored to normal condition merely by replacing the sheet of fusible combustible materials, or with a greatly reduced chance of weakening the steel supporting members in the case of the structure covered with corrugated iron. Furthermore, manual fire fight ing is made easier with these automatic facilities to permit the escape of heat and smoke.

It should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and equivalents which fall within the scope of the appended claims. Iclaim: 1 i

-1. A building construction comprising a roof having supporting members and covering material' at least a portion of which comprises fusible sheet material exposed on both sides so that the rising column of heat from alocalized fire beneath the roof can quickly form a vent opening to permit the escape of the heat, thereby retarding the spread of the fire. I V

2. A building construction comprising a roof having supporting members and covering material at least 9, portion of which comprises fusible sheet metal exposed on both sides so that the rising .column 'of heat from a localized fire beneath the roof can quickly form a vent openin to permit the escape of the heat, thereby retarding the spread of the fire.

"3. A building construction comprising a roof having supporting members and covering material recurrent sections of which comprise fusible sheet material exposed on both sides so that the rising column of heatfrom a localized fire beneath one of theseetions can quickly form a vent opening to permit the escape of the heat, thereby retarding the spread of the fire. V 4. A building construction comprising a roof having openings at recurrent intervals and closures for the openings which comprise fusible sheet material exposed on both sides so that the rising columncf heat from a localized fire beneath one of the closures can quickly burn out the closure to permit the escape of the heat through the opening, spread of the fire. 4 I y j a V 5.--A:.building construction comprising a roof having supporting members and covering mate- .rial at least a portion of which comprises fusible sheet material exposed on both sides so that the .rising'column of heat from a localized fire beneath the roof can quickly form a vent opening to permit the escape of the heat, and a fire curtain depending from the roof adjacent said portion to assist in directing the heat to said portion.

6. A building construction comprising a roof having supporting members and covering material at least a portion of which comprises fusible 7 sheet metal exposed on both sides so that the rising column of heat from a localized fire be-, neath the roof can quickly form a vent opening to permit the escape of the heat, and a fire, curtain depending from the roof-adjacent said portion to assist in directing the heat to said portion.

'7. A building construction comprising a roof having supporting members and coveringmaterial recurrent sections of which comprise fusible sheet material exposed on both sides so that the rising column of heat from a localized fire beneath one of the sections can quickly form a vent opening to permit the escape of the heat,

and fire curtains depending from the roof be tween the sections to assist in directing the heat from the fire to the section thereabove. r

8. A building construction comprising a roof having openings at recurrent intervals and closures for the openings which comprise fusible sheet material exposed on both sides so that the rising column of heat from a localized fire beneath one of the closures can quickly burn out the closure to permit the escape of the heat through the opening, and fire curtains depending from the roof between the openings to assist in directing the heat from the fire to the opening thereabove.

ARTHUR L. BROWN.

thereby retarding the