Patent Application
20130130606
This application is directed, in general, to a chimney shield system and, more specifically, to a swivel joint for a chimney shield.
Modern day chimneys often consist of sheet metal that are formed into elongated, cylindrically shaped pipe joints that are joined together to span the distance from the fireplace or firebox to outside the structure being heated. In most instances, due to the fact that the sheet metal is typically very thin, many governmental regulations now require that the chimneys be additionally insulated to protect against the possibility of fires occurring due to the hot chimney pipe. To address this issue, manufacturers have developed an insulative shield that encompasses the chimney. These shields are also sheet metal that are formed into elongated, cylindrically shaped pipe joints that typically have an insulative material, such as foam or fiberglass located between two cylindrically formed pieces of sheet metal. The insulative shield has an inner diameter that is larger than the chimney, which allows it to be wrapped around the chimney. Typically, the inner diameter is large enough to allow a gap to exist between the outer wall of the chimney and the inner wall of the shield, thereby providing an additional insulative effect.
In original construction, these shields are placed about the chimney before the chimney is boxed in with wall materials. As such, the installer can easily access all sides of the shield joints, which allows the installer to adequately secure the joints together. However, in after-construction situations, these shields can be very difficult to install because, often times, only one side of the chimney is exposed. This makes securing the joints together properly more difficult, because all sides of the shield cannot be reached due to the limited access space.
One aspect of the present disclosure provides a swivel joint for a chimney shield. In one embodiment, the swivel joint comprises a first cylindrical member and a second cylindrical member having an end portion received in an end portion of the first cylindrical member and that is rotatably coupled to the first cylindrical member. The first and second cylindrical members extend along a central longitudinal axis. Also, the first and second cylindrical members rotate independently of one another about a plane perpendicular to the central longitudinal axis.
Another aspect provides a chimney shield system. In one embodiment, the chimney shield system comprises a first cylindrical shield member, a second cylindrical shield member, and a swivel joint. The swivel joint includes a first cylindrical member and a second cylindrical member that is rotatably coupled to the first cylindrical member. The first and second cylindrical members extend along a central longitudinal axis. The first and second cylindrical members rotate independently of one another about a plane perpendicular to the central longitudinal axis, and the swivel joint is configured to couple the first and second cylindrical members together.
Another aspect provides a method of manufacturing a swivel joint for a chimney shield. In one embodiment, the method comprises providing a first cylindrical member, providing a second cylindrical member, and rotatably coupling the first cylindrical member to the second cylindrical member by inserting an end portion of the second cylindrical member into an end portion of the first cylindrical member. The first and second cylindrical members extend along a central longitudinal axis, and the first and second cylindrical members rotate independently of one another about a plane perpendicular to the central longitudinal axis.
Reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
As stated above, in after-construction installation situations, installing a shield over a chimney requires opening a side of the chimney enclosure to gain access to the chimney, while minimizing structural damage to the existing chimney enclosure. Once access to the chimney is obtained through the opened side, the shields are then connected to the adjacent shields, e.g., top and bottom shields, across the opened side. The opened side, however, only exposes a fraction of the shield's circumference, making its connection with the adjacent shields weak. The chimney shield system becomes vulnerable to collapses and failure, e.g., misalignment, especially in the areas that are not vertically oriented.
Described herein are embodiments of a swivel joint that can be used to install a chimney shield about an existing chimney, and methods of making it such that the joint facilitates stronger and easier connections among the joints of the shield. The swivel joint comprises cylindrical members that can rotate independently of each other such that, once one member is coupled to a chimney shield, the coupled member and chimney shield can be swiveled or rotated together, which allows the installer to couple the chimney shield joints together about their entire circumference.
As seen in the embodiment of
In an installation application, one wall of a chimney duct 120 is removed, thereby allowing access to the existing chimney. A swivel joint 140 is attached to an exposed portion of collar that encompasses the chimney 115. A chimney shield 135 may then be wrapped around the chimney, and one of its ends can be attached to the swivel joint 140. A screw is placed through the coupling end of the swivel joint 140 and the chimney shield 135. The rotation of the swivel joint 140 allows one of the cylindrical members of the swivel joint 140 and the chimney shield 135 to which it is attached to be rotated, at which point another screw can be used to further couple the swivel joint 140 and the chimney shield 135 together. This process is repeated until the joints have been rotated as much as 360 degrees. Then, a second swivel joint 140 is attached to the opposite end of the chimney shield 135 and attached in the same manner as just described. This process is repeated until all chimney shield joints have been installed.
First and second cylindrical members 205, 210 are rotatably coupled together in a way that one member can rotate independently of another member about a plane 220, which is perpendicular to the central longitudinal axis 215. It should be understood that the swivel joint 140 can have more than two cylindrical members so that it will have more than one swiveling joint that is capable of independently rotating about the plane 220. This rotation about the plane that is perpendicular to the central longitudinal axis 215 provides advantages over conventional joints that are designed to rotate about a plane that is not perpendicular to their central longitudinal axis. Such conventional designs cannot be used in existing chimneys in that the joints cannot be rotated sufficiently to provide adequate attachment points, because the wall of the chimney duct would block the non-perpendicular rotation of the swivel joint.
Swiveling portion 305 of the first cylindrical member 205 comprises one or more grooves 325. Grooves 325 are formed in an outer surface of the swiveling portion 305 and extend parallel to the plane 220, which is perpendicular to the central longitudinal axis 215.
Swiveling portion 310 of the second cylindrical member 210 comprises a groove 330 and a ridge 335. Groove 330 and the ridge 335 are formed in an outer surface of the swiveling portion 310 and extend parallel to the plane 220 which is perpendicular to the central longitudinal axis 215. As explained below, the grooves 325, 330 cooperatively engage each other when the first and second cylindrical members 205, 210 are coupled together to provide rotation of the first and second cylindrical members 205, 210 with respect to each other.
First and second cylindrical members 205, 210, in certain embodiments may also comprise a plurality of optional, attachment orifices 405 around their respective coupling portions 315, 320. Orifices 405 are located adjacent an end of the coupling portions 315, 320, so that each of the orifices 405 will line up with orifices in the connecting shield member and receive a fastening device, such as a screw. In this embodiment, each of the orifices 405 of the swivel joint 140 is equally spaced apart from each other along the direction perpendicular to the central longitudinal axis 215. While each the first and second cylindrical members 205, 210 of this embodiment has four orifices 405, the number of orifices may vary depending on the applications and circumstances. Moreover, the orifices 405 may receive fastening devices other than screws depending on the applications and circumstances. In other embodiments, however, the orifices 405 may not be present and the attachment of the swivel joint 140 to the shield member may simply be made by punching a screw through both of the joints, which is often done in the assembly of sheet metal joints.
In a method of manufacturing embodiment, the first cylindrical member 205, as discussed above, is provided. As used herein and in the claims, “provided or providing” includes those instances where the recited component is fabricated by the manufacturer or obtained from an outside source (e.g, subsidiary) or a third party source. The second cylindrical member 210, as discussed above, is also provided. The first and second cylindrical members 205, 210 are rotatably coupled together by inserting the swiveling portion 310 of the second cylindrical member 210 into the swiveling portion 305 of the second cylindrical member 205, until the groove 330 of the second cylindrical member 210 is received in the groove 325a of the first cylindrical member 205. The first and second cylindrical members 205, 210 have a height that extends along a central longitudinal axis. The cooperative engagement of the grooves 325a and 330 are such that the first and second cylindrical members 205, 210 are allowed to easily rotate independently of one another about a plane 220 perpendicular to the central longitudinal axis 215.
From the foregoing, a swivel joint is provided that allows for a shield member to be installed about an existing chimney. The free rotation of the swivel joints allows an installer to rotate the swivel joint and the chimney shield to which it is to be attached as much as 360 degrees. This allows the installer to place as many screws as necessary to provide adequate coupling and support between the swivel joint and the chimney shield, even when only one side of the chimney is exposed.
Those skilled in the art to which this application relates will appreciate that other and further additions, deletions, substitutions and modifications may be made to the described embodiments.
