Patent Application
20060121841
The present invention relates generally to chimney liners and more particularly relates to a chimney liner tee that can be assembled by snapping the pieces together without the need for tools or user manipulation of any assembly fitting.
Old chimneys are often relined with stainless-steel chimney liners in order to increase safety and improve performance. Relining can eliminate air leaks, increase safety by adding another barrier between hot exhaust gases and the structure of the building, and allow for a better fit between the chimney size and the heat source.
However, it is often difficult to install such liners because of the limited amount of space in a chimney and the desire to avoid damage to the chimney by creating as few holes as possible for the purposes of installation. This can make assembly of the different parts of the chimney liner difficult. One previously recognized problem area is the connection between individual appliances, such as a boiler, water heater, or a fireplace, and the main chimney liner. Usually a T-shaped joint called a “tee” is used to allow a horizontal connection to the appliance in question from the vertically oriented main chimney liner. However, the liner and tee cannot be installed pre-assembled because the tee, with the horizontal connector attached, would be too large to feed into the chimney from the roof opening, which is the normal method of installation. Therefore, a tee is installed in two parts, with a main section that can be inserted through the length of the chimney and a horizontal section that enters the chimney through an opening in the side of the chimney near an appliance.
There are numerous ways of joining the main section of the chimney liner and the horizontal section of liner connected to the appliance. One such system is similar to a large hose clamp. A stainless-steel band that can be adjusted with a screwdriver is attached to the horizontal section, which is installed first. The main chimney liner with a cut-out in the correct position is then dropped into place vertically down the chimney and through the band. The installer then tightens the band using a screwdriver to pull the pieces together in order to establish a tight fit.
Another known design uses two pairs of threaded brackets, with a threaded hole drilled through each bracket. One pair is mounted on the inner wall of the main chimney liner at the cut-out portion, extending inwardly into the cut-out portion. The other pair is mounted on the inner wall of the horizontal connection from the appliance and extend inwardly towards the center of the horizontal connection. The horizontal connection is held so that the holes in the brackets on the horizontal connection and the main section are in alignment, and then screws are inserted through the holes and tightened to join the two sections together.
Another previously known construction is described in U.S. Pat. No. 6,588,802. This configuration uses clamps to join the main chimney liner and the horizontal connection together. The clamps consist of a generally U-shaped locking member, a lever, and a mounting bracket. The clamps are connected to either the wall adjacent the cut-out section in the main chimney liner, or the horizontal connection. The U-shaped locking member on each clamp attaches to a hook on the inner wall of the other piece, either the main chimney section or horizontal connection. An installer will manipulate the lever of the clamps to draw the two pieces together, and then the clamps are locked, holding the pieces together.
All of the above systems require the installer to manually actuate the locking mechanism, either by tightening the stainless steel band, tightening the screws in the brackets, or manually moving the lever on the connecting clamps. Consequently, the horizontal connection piece must be shorter than the length of the installer's arm in order to allow the installer to reach the connection system and operate it. The connection systems also require either the use of fasteners, as in the bracket design, or movable parts, such as the stainless-steel band or clamp-connected systems.
As a result, there is a need for a chimney liner tee that can be constructed with a horizontal connector longer than the length of the installer's arm and that can be assembled without the use of tools.
Also, there is a need also exists for a connection system that does not make use of relatively expensive and inefficient moving parts and is both effective and easy to use.
One object of the present invention is to provide a chimney liner tee that does not require the installer to fasten the pieces together by direct manipulation of a fastener. This allows for the use of horizontal connections with lengths greater than the arm-length of the installer. Another object is to simplify the construction of the chimney liner tee and reduce manufacturing, assembly and installation costs.
These objectives are achieved in the present invention by a snap-connect chimney liner tee that is assembled from two parts. The first part of the chimney liner tee is the main section. The main section extends the length of the chimney when installed. The main section includes a cut-out portion of the liner wall that is located near the appliance to be vented and that is variably sized to accommodate the exhaust of the appliance. Two protrusions extend outwardly from the external surface of the main section near the cut-out portion. These protrusions may be of any shape that will allow the holes in the connecting end of the connecting section to slide over them when the two pieces of the tee are pushed together, but will then lock the connecting section in place.
The second part of the chimney liner tee is the connecting section. The connecting section links the appliance whose exhaust is to be vented to the main section. The connecting section is a generally cylindrical pipe section having a diameter which is preferably slightly larger than the cut-out portion of the main section. The connecting end of the connecting section shaped to engage the main section and fit tightly around the cut-out portion of the main section, forming the chimney liner tee. The connecting end preferably includes two holes positioned and sized to engage with the protrusions on the main section and cooperate to establish a snap connection between the two sections.
In order to assemble the tee, the connecting end of the connecting section is aligned with the cut-out portion, and force is applied to push the two pieces together. The shape of the two pieces forces the edges of the connecting end, where the holes are positioned, over the protrusions. As force is applied, the holes on the connecting end will be aligned with the protrusions, allowing the edges of the connecting end to snap back down against the surface of the wall of the main section, locking the connecting section in place. No further action on the part of the installer is needed to fasten the two parts of the chimney liner tee together.
In one embodiment, the protrusions are substantially cylindrically shaped, which allows the use of round holes in the connecting end, which can be easily created by one skilled in the art. Such cylindrical pieces are also readily available commercially.
In another embodiment, the protrusions take the shape of right triangular prisms, with the larger face of the prism attached to the wall of the main section and the face that forms the hypotenuse facing substantially the same direction as the cut-out. This orients the prism as a ramp facing away from the cut-out portion. Rectangular holes can then be used in the connecting end. When pushing the pieces together, the edges of the connecting end slide up the ramp of the protrusion until reaching the edge and snapping back to rest against the wall of the main section, locking the two pieces together.
In another embodiment, the main section and the connecting section are rectangular in shape and the protrusions take the form of right triangular prisms similar in shape and configuration to the second embodiment.
In the preferred embodiment, the main section and the connecting section are tubular, and the protrusions are substantially cylindrically shaped with a groove perpendicular to the longitudinal axis of the protrusion cut into the protrusion, on the side facing away from the cut-out portion. The matching holes in the connecting end are substantially circular in shape. As the edges of the connecting end are pushed over the protrusions, the holes line up with the protrusions, snapping into place. When assembled, the periphery of the holes engage the grooved area of the protrusion. The walls of the groove keep the edges of the connecting end in locked engagement, and help ensure a tight fit between the main section and the connecting section of the tee.
It will be appreciated that the position of the protrusions and holes can be interchanged, i.e., the main section can be provided with receiving holes and the nose piece, or connecting section, provided with protrusions suitably sized and shaped to engage the holes in the main section.
The illustrated embodiment of the snap-tight chimney liner tee, according to the present invention, consists of a main section 1 and a connecting section 2. Turning our attention to
The connecting section 2 is tubular with a diameter at least slightly greater than that of the cut-out portion of the main section. The connecting end 6 of the connecting section 2 is shaped to fit closely to the surface of the main section 1. Preferably, the upper and lower edges of the connecting section are each bent outwards to form a flange 7 that engages the outer surface of the main section. A heat-resistant sealant, such as furnace cement, can be applied to the flange prior to assembly to further prevent leakage of exhaust gases after the tee assembly is complete. The sides of the connecting edge form two arms 8 to engage the protrusions on the main section. Each arm of the connecting edge contains a hole 9 shaped to fit the protrusion. The edge 10 of each connecting end that extends past the hole is bent outwardly slightly to facilitate assembly.
In order to assemble the tee, the installer merely has to push the connecting section 2 against the main section 1. The relative shapes of each section urge the arms 8 of the connecting end 6 into alignment with the protrusions and allow engagement with them. As can be seen in
A second embodiment of the invention is shown in
The foregoing merely illustrates the principles of the invention. It will thus be appreciated that those skilled in the art will be able to devise numerous systems, apparatus and methods which, although not explicitly shown or described herein, embody the principles of the invention and are thus within the spirit and scope of the invention as defined by the appended claims.
For example, the protrusions on the main section and the holes on the connecting end may be of different shapes. Furthermore, the position of the protrusions and receiving openings which establish the snap-tight engagement can be reversed. In this manner, the protrusions would be part of the connection section 2 and the openings associated with main section 1. In each of these embodiments, the tee assembly can be completed “blind” and without the need for the installer to reach in and through the connecting piece to the interface region to complete the assembly.
