Patent Application
20110036509
Embodiments of the present invention are directed to movable partitions used as fire barriers, and to methods of forming and using such movable partitions.
Movable partitions are utilized in numerous situations and environments for a variety of purposes. Such partitions may include, for example, a movable partition comprising foldable or collapsible doors configured to enclose or subdivide a room or other area. Often such partitions may be utilized simply for purposes of versatility in being able to subdivide a single large room into multiple smaller rooms. The subdivision of a larger area may be desired, for example, to accommodate multiple groups or meetings simultaneously. In other applications, such partitions may be utilized for noise control depending, for example, on the activities taking place in a given room or portion thereof.
Movable partitions may also be used to provide a security barrier, a fire barrier, or both a security and a fire barrier. In such a case, the partition barrier may be configured to close automatically upon the occurrence of a predetermined event such as the actuation of an associated alarm. For example, one or more accordion or similar folding-type partitions may be used as a security barrier, a fire barrier, or both a security and a fire barrier wherein each partition is formed with a plurality of panels connected to one another with hinges. The hinged connection of the panels allows the partition to fold and collapse into a compact unit for purposes of storage when not deployed. The partition may be stored in a pocket formed in the wall of a building when in a retracted or folded state. When the partition is deployed to subdivide a single large room into multiple smaller rooms, secure an area during a fire, or for any other specified reason, the partition may be extended along an overhead track, which is often located above the door in a header assembly, until the partition extends a desired distance across the room. The deployed partition may extend from a jamb, located in the wall storage pocket at the proximal end of the track, to a lead post, which extends toward the distal end of the track and provides a connection with a mating striker or receiver post.
Generally, a fire barrier system or assembly provides a barrier to fire, smoke, and heat. Thus, a fire barrier may retard or resist the deleterious effects of fire, smoke, and heat for a certain period of time. A number of standardized tests that test the effectiveness of fire barrier assemblies have been developed for use in the building industry. These are published, for example, in the International Building Code (IBC), and by the National Fire Protection Association (NFPA), UNDERWRITERS LABORATORIES® (UL), and the American Society for Testing and Materials (ASTM), among others. Various agencies test fire barriers using these standardized tests, and assign ratings to fire barriers that indicate their effectiveness at slowing the progress of a fire. Barrier testing agencies include Intertek Testing Services, UNDERWRITERS LABORATORIES®, Chiltern International Fire, Ltd., and Warrington Fire Research, among others. Ratings of fire barrier assemblies are generally provided in minutes, and typically vary from 20 minutes to 180 minutes. Examples of fire barrier assembly standards and testing methods can be found in UNDERWRITERS LABORATORIES® UL 10B.
In order to provide an effective fire barrier, the track, lead post, and jamb, along with the movable partition and surrounding walls, must provide some level of fire resistance. However, the track, lead post, and jamb may include some open spaces or gaps through which flames may penetrate, reducing the ability of the apparatus to act as an effective fire barrier. Some conventional hinged doors and interior windows have incorporated intumescent materials into their design in an attempt to seal off gaps in the event of a fire. When a fire breaks out and temperatures around the intumescent material escalate sufficiently, an intumescent material may foam, expand, char, and solidify to provide a strong, fire-resistant seal. However, intumescent material that is improperly installed, tampered with, or damaged may not behave as intended and fail to provide an effective seal. Further, intumescent material may expand in unexpected ways or directions, failing to seal of the intended gaps. Finally, uncontrolled intumescent material may ignite, effectively transforming into a conduit for the fire to pass through the intended barrier.
In some embodiments, the present invention includes movable partition systems. The movable partition systems comprise a movable partition and an intumescent material positioned to seal at least a portion of a gap at a periphery of the movable partition.
In additional embodiments, the present invention includes movable partition systems including a first mass of intumescent material and a second mass of intumescent material. The second mass of intumescent material is spatially separated from the first mass of intumescent material. The first and second masses of intumescent material are shaped an positioned to expand toward one another, contact one another, and form a seal therebetween extending along at least a portion of a periphery of the movable partition when the movable partition is exposed to fire.
In still further embodiments, the present invention includes methods of providing a fire barrier, comprising extending a movable partition along a track assembly. The methods of providing a fire barrier further include heating an intumescent material to cause the intumescent material to expand, char, and form a seal extending along at least a portion of a periphery of the movable partition.
In other embodiments, the present invention includes methods of installing a movable partition. At least one mass of intumescent material is positioned to seal at least a section of a cap at a periphery of a movable partition when the at least one mass of intumescent material is exposed to fire.
While the specification concludes with claims particularly pointing out and distinctly claiming that which is regarded as the present invention, the advantages of embodiments of the invention may be more readily ascertained from the description of embodiments of the invention when read in conjunction with the accompanying drawings, in which:
Some illustrations presented herein are not meant to be actual views of any particular movable partition system or component thereof, but are merely idealized representations employed to describe embodiments of the present invention. Additionally, elements common between figures may retain the same numerical designation.
Referring to
To deploy the movable partition 12 to an extended position, the movable partition 12 is moved along the tracks 18. Deployment may be achieved manually or automatically with an automatic closure system 56, as shown in
The movable partition system 10 also includes a track assembly 34. The movable partition 12 may be suspended from and supported by one or more tracks 18 of the track assembly 34. As shown, the track assembly 34 may be located within or adjacent a header protruding into the space where the movable partition 12 is located. In alternative embodiments, the track assembly 34 may be mounted to the ceiling or mounted to within an overhead structure, such as a recessed surface, such that the bottom surface of the track assembly 34 is flush with the ceiling. Furthermore, the movable partition 12 may be supported by the floor below the movable partition 12, and the track assembly 34 may simply serve as a guide for the movable partition 12. The movable partition 12 may include means to engage with the one or more tracks 18, such as slide mechanisms or pin and roller assemblies, so that the movable partition 12 is horizontally extendable along the length of the tracks 18.
Thus, the header assembly 34, the lead post 26, and the jamb 32 largely define what may be termed the border, periphery, or perimeter of the movable partition system 10. Each of the components defining the perimeter of the movable partition system 10 typically includes structures defining spaces or gaps that, when left without means to close the gaps, may be relatively weaker points in the fire barrier.
A partial cross-sectional view of a track assembly 34 that includes the tracks 18 is shown in
An enlarged, partial cross-sectional view of one track 18 of the track assembly 34 is shown in
The track 18 may be at least partially surrounded by one or more shrouds 36, shown here as two generally “C”-shaped channels fitted tightly on the lateral sides of the track 18. In other embodiments, the shrouds 36 may comprise one integral piece or additional pieces, and may surround the track 18 more completely or less completely. The shrouds 36 may be of any material suitable for use in a fire barrier, such as steel. The shrouds 36 defines spaces or gaps between the bottom surfaces 38 and 39 of the first and second cup-shaped rails 72 and 74 of the track 18 and the shrouds 36.
In accordance with embodiments of the present invention, an intumescent material may be positioned to seal at least a portion of a gap at a periphery of the movable partition 12, as discussed in further detail below. As used herein, the term “intumescent material” means and includes any material that is formulated to swell (increase in volume) and scorch without significantly combusting, when exposed to heat, and that is used for fire protection.
By way of example and not limitation, a strip of intumescent material 40 may be interposed between the bottom surfaces 38 and 39 of the cup-shaped rails 72 and 74 and the shroud 36 on each side of the opening leading to the interior space within the track 18. This technique at least substantially confines the strips of intumescent material 40 on three sides and allows expansion of the intumescent material 40 to occur in the direction parallel to the bottom surfaces 38 and 39 of the track 18, as indicated by arrows 58 and 60. When exposed to heat, each strip of intumescent material 40 may expand toward the strip of intumescent material 40 located under the opposing cup-shaped rail of the track 18. Each strip of intumescent material 40 may need to expand by a fraction of an inch to meet and form a seal across the entire bottom surface of the track 18. As part of this process, the seal forms around the pin and roller assemblies that roll in the track 18 under normal operation. Both the shroud 36 and the strips of intumescent material 40 may extend for the entire length of the track 18, or may only be located intermittently in portions thereof.
A partial cross-section of the lead post 26 of
A partial cross-section of a jamb 32 in accordance with an embodiment of the present invention is shown in
Strips of intumescent material 40 may be adhered to the outside return surfaces 52 and 54 of the jamb 32, which are configured to meet the jamb stops 50. The strips of intumescent material 40 may extend for the entire length and height of the outside return surfaces 52 and 54, or may only be adhered to selected portions thereof. The outside return surfaces 52 and 54 may be formed by making a return bend on the jamb 32 itself, or by fastening an angled piece to the ends of the jamb 32. The outside return surfaces 52 and 54 may not be exposed to view under normal operation and are protected from friction between the jamb stop 50 and the jamb 32. Under fire conditions, the strips of intumescent material 40 expand inside the pocket 20 until they form a seal between the outside return surfaces 52 and 54 of the jamb 32 and the pocket walls.
The strips of intumescent material 40 that may be located in the track 18, lead post 26, and jamb 32 may be of any intumescent material 40 known in the art to be suitable for fire barrier applications. For example, the intumescent material may comprise a soft char or a hard expanding char producer, such as sodium silicate, graphite, or a sodium silicate or graphite based intumescent material, typically included as fibers in a polymer matrix. The intumescent material may further include reinforcing mineral fibers. Further, the intumescent material may include at least one hydrate, which may have a cooling effect as water vapor is released when the material is exposed to fire. While the intumescent material has heretofore been referred to as a flexible strip 40, it may be alternatively be applied or provided in the form of a resin, a spray, or a putty.
The strips of intumescent material 40 may be of any size or shape appropriate for the selected application and sufficiently small to fit within the gaps formed by the various structures as described above. For example, the strips of intumescent material 40 may have a rectangular cross-section of about ½ inch wide and about 1/16 inch thick. Intumescent materials suitable for use in a movable partition system 10 and commercially available may include FIREFREE 88™, available from Firefree Coatings, Inc. of San Rafael, Calif., FLAMESTOP V™, available from Flame Stop, Inc. of Fort Worth, Tex., FIRETEMP® Intumescent Strip, available from Fire Protection Systems of Denver, Colo., 3M™ EXPANTROL™ Flexible Intumescent Strip, available from 3M of St. Paul, Minn., TECNOFIRE® 2006, available from Lorient North America, Inc. of Lexington, Ky., and BLAZE SEAL, available from RectorSeal of Houston, Tex.
As shown in
Various means may be used to displace the movable partition 12 from a stowed condition to a deployed condition and vice versa. In one embodiment, an appropriate actuator may be used to displace the movable partition 12. For example, a drive may include a motor 60 coupled to a pulley or gear 62 configured to drive a transmission member such as a belt or chain 64.
A portion of the belt or chain 64 may be coupled to a trolley 66 that is configured to ride along the track 18. The trolley 66 may be coupled to a component of the movable partition 12 such as, for example, the lead post 26. Thus, actuation of the motor 60 and belt or chain 64 in a first direction results in displacement of the trolley 66 and lead post 26 so that the movable partition 12 may be deployed. Actuation of the motor 60 and belt or chain 64 in a second direction results in displacement of the trolley 66 and lead post 26 so that the movable partition 12 may be retracted.
Additionally, various sensors, switches, and control electronics may be employed in association with such a drive to assist in the control of the movable partition system 10. These electronic components may be generally and collectively referred to as a movable partition controller 68. While shown as a box on the first wall 22, those of ordinary skill in the art will recognize that the sensors, switches and other electronic components may be distributed at various locations in and around the movable partition system 10. Control electronics may include, for example, a switch or actuator commonly referred to as “panic hardware,” not shown here in detail. Actuation of the switch allows a person located on one side of the movable partition system 10 (e.g., in room 70) to cause the movable partition 12 to open if it is closed, or to stop while it is closing, so as to provide access through the barrier formed by the movable partition 12 for a predetermined amount of time.
It is noted that, while the above description has been more directed to an embodiment including a single movable partition 12 extending from the first wall 22 to the second wall 22′, other movable partitions may be utilized. For example, a two-door, or bi-part partition configuration may be utilized wherein two similarly configured partitions extend across a space and join together to form an appropriate barrier as will be appreciated by those of ordinary skill in the art.
The motor 60 and movable partition controller 68 need electric power to operate. This electrical power may be provided by a power supply, which may be placed locally, for example, perhaps at a location within the pocket 20. Alternatively, the power supply may be placed remotely from the movable partition system 10 with power lines running from a battery-backed power supply to the motor 60 and movable partition controller 68. The movable partition controller 68, acting in concert with the power supply and actuation hardware, may be referred to collectively as an automatic closure system 56. In use, the automatic closure system 56 may be configured to extend the movable partition 12 upon the occurrence of a predetermined event, such as the actuation of an associated alarm.
While the invention may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described in detail herein. However, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the following appended claims.
