Patent Publication Number: US-2009223504-A1

Title: Fireplace flue sealing device

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATION 
     This application claims priority to and the benefit of, pursuant to 35 U.S.C. §119(e), U.S. provisional patent application Ser. No. 61/068,609, filed Mar. 7, 2008, entitled “Wood Burning Fireplace Energy Loss Preventer,” by Michael A. Williams, the content of which is incorporated herein in its entirety by reference. 
    
    
     Some references, which may include patents, patent applications and various publications, are cited and discussed in the description of this invention. The citation and/or discussion of such references is provided merely to clarify the description of the present invention and is not an admission that any such reference is “prior art” to the invention described herein. All references cited and discussed in this specification are incorporated herein by reference in their entireties and to the same extent as if each reference were individually incorporated by reference. 
     FIELD OF THE INVENTION 
     The present invention generally relates to a fireplace, and more particularly, to a flue sealing device to provide sealing at the bottom of a fireplace flue so as to prevent the loss of conditioned air through an unused fireplace and save energy costs. 
     BACKGROUND OF THE INVENTION 
     Fireplaces are of popular devices for heating in residential and commercial buildings. A fireplace usually has a fireplace opening connected to a chimney flue that is open to the outside of the building. When in use, the waste gas generated from the fireplace passes up through the flue and exits the chimney in a conventional fashion. 
     When the fireplace is not in use, however, the fireplace opening and chimney flue form a passage through which heated air or cooled air can escape from the interior of the building. Although most fireplaces contain fireplace dampers at the bottom of the flue or immediately above the fireplace opening, these fireplace dampers do not make a perfect seal for the chimney flue, and allow significant loss of heated air during winter and cooled air in summer through the chimney flue. 
     Numerous innovations for flue seals have been provided for a better seal and thus reduce the amount of heat lost through the chimney flue. For example, U.S. Pat. No. 4,964,438 to Welty discloses a foam air duct plug provided for insertion up into an open end of a fireplace flue during periods of nonuse to prevent or limit the escape of cooled or heated air through the flue in a dwelling, public building or structure thereof. The plug further provides a depending base for ease of removal from the flue when it is determined that the flue should be used. 
     U.S. Pat. No. 4,762,115 to Penner discloses a device for plugging a chimney flue when not in use. The device comprises an elongate semi-rigid wand which can be maneuvered by manual movement of one end so that the opposed end can be inserted into the chimney flue. The opposed end carries an inflatable balloon which can be inflated to grasp the inner surface of the flue by valve arrangement at the lower end. 
     However, these fireplace plugs are structurally complicate and very expensive. Another disadvantage of these fireplace plugs is the lack of convenience associated with these plugs during installation. 
     Therefore, a heretofore unaddressed need still exists in the art to address the aforementioned deficiencies and inadequacies. 
     SUMMARY OF THE INVENTION 
     In one aspect, the present invention relates to a fireplace flue sealing device. In one embodiment, the fireplace flue sealing device includes a plate having a first surface and an opposite, second surface, a gasket attached to the first surface of the plate, a shaft having a first end and an opposite, second end defining a shaft body portion therebetween, the first end of the shaft being mounted onto the plate such that the shaft body portion of the shaft extends outwards from the second surface of the plate, and a tubular base having a first end and an opposite, second end defining a base body portion therebetween, the tubular base being adapted for releasably receiving the shaft body portion of the shaft from the first end of the tubular base. 
     The fireplace flue sealing device also includes a locking mechanism having a locking position and a releasing position, the locking mechanism being positioned in relation to the tubular base and engaged with the shaft body portion of the shaft such that when the locking mechanism is in the locking position, no motion of the shaft body portion of the shaft relative to the tubular base is allowed, and when the locking mechanism is in the releasing position, the shaft body portion of the shaft is movable back and forth relative to the tubular base. 
     In one embodiment, the fireplace flue sealing device further includes a cup attached to the first end of the tubular base, the cup defining a bore  162  adapted for releasably receiving the shaft body portion of the shaft. 
     In one embodiment, the tubular base has a first window  141  having a bottom edge  143  and a second window  145  having a bottom edge  147  formed oppositely on the tubular body portion of the tubular base, the bottom edge  143  of the first window  141  and the first end defining a first distance, H 1 , therebetween, and the bottom edge  145  of the second window  145  and the first end defining a second distance, H 2 , therebetween, where H 2 &gt;H 1 . 
     The locking mechanism in one embodiment comprises a locking member placed across the first window  141  and a second window  145  of the tubular base, the locking member defining a bore adapted for releasably receiving the shaft body portion of the shaft; and a resilient spring having a first end and an opposite, second end, configured to be positioned inside the tubular base such that the first end and the second end are in contact with the cup and the locking member, respectively. When the resilient spring is in its extended position, the locking mechanism is in the locking position. When the resilient spring is in its retracted position, the locking mechanism is in the releasing position. 
     In assembly, the second end of the shaft passes, in turn, through the bore  162  of the cup, the resilient spring of the locking mechanism, and the bore of the locking member of the locking mechanism such that the shaft body portion of the shaft is releasably received in the tubular body portion of the tubular base. As such, the locking mechanism is normally in the locking position. 
     In operation, (a) a force is applied to the locking member of the locking mechanism to cause the resilient spring of the locking mechanism to move from its extended position to its retracted position so that the locking mechanism is in the releasing position; (b)the plate is moved to a desired position by moving the shaft; and (c) the applied force is released from the locking member of the locking mechanism, thereby causing the resilient spring of the locking mechanism to move from its retracted position to its extended position so that the locking mechanism is in the locking position. 
     The plate, the shaft, the tubular base and the locking mechanism are made of rigid materials. In one embodiment, the plate, the shaft, the tubular base and the locking mechanism are made of metals, plastic, wood and/or fiberglass. 
     These and other aspects of the present invention will become apparent from the following description of the preferred embodiment taken in conjunction with the following drawings, although variations and modifications therein may be affected without departing from the spirit and scope of the novel concepts of the disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings illustrate one or more embodiments of the invention and, together with the written description, serve to explain the principles of the invention. Wherever possible, the same reference numbers are used throughout the drawings to refer to the same or like elements of an embodiment, and wherein: 
         FIG. 1  shows a perspective view of a fireplace flue sealing device according to one embodiment of the present invention; 
         FIG. 2  shows a cross-sectional view of the fireplace flue sealing device shown in  FIG. 1 ; 
         FIG. 3  shows a partially cross-sectional view of the fireplace flue sealing device shown in  FIG. 1 ; and 
         FIG. 4  shows another partially cross-sectional view of the fireplace flue sealing device shown in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention is more particularly described in the following examples that are intended as illustrative only since numerous modifications and variations therein will be apparent to those skilled in the art. Various embodiments of the invention are now described in detail. Referring to the drawings, like numbers indicate like parts throughout the views. As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein and throughout the claims that follow, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise. As used herein, “around”, “about” or “approximately” shall generally mean within  20  percent, preferably within 10 percent, and more preferably within 5 percent of a given value or range. Numerical quantities given herein are approximate, meaning that the term “around”, “about” or “approximately” can be inferred if not expressly stated. 
     The description will be made as to the embodiments of the present invention in conjunction with the accompanying drawings in  FIGS. 1-4 . In accordance with the purposes of this invention, as embodied and broadly described herein, this invention, in one aspect, relates to a fireplace flue sealing device. The fireplace flue sealing device is designed to augment the damper system. It includes a rigid plate with a gasket seal around its perimeter which is brought against the bottom of the fireplace flue to prevent the escape of heated air or cooled air in the interior of a building. The plate is held in place by an adjustable assembly to accommodate fireplaces of different size. The body of the assembly contains a smooth shaft and a locking mechanism that allows for adjustment of height. The device is placed inside the fireplace when no fire is burning and must be removed prior to starting a fire. 
     Referring to  FIG. 1-4 , the fireplace flue sealing device  100  includes a plate  110  having a first surface  112  and an opposite, second surface  114 , and a gasket  120  attached to the first surface  112  of the plate  110 , and a shaft  130  having a first end  132  and an opposite, second end  134  defining a shaft body portion  136  therebetween, the first end  132  of the shaft  130  being mounted onto the plate  110  such that the shaft body portion  136  of the shaft  130  extends outwards from the second surface  114  of the plate  110 . In practice, the plate  110  can be in any geometric shapes and sizes that fit the bottom of a fireplace flue to be sealed. The gasket  120  is attached to the plate  110  by glue or the like. The first end  132  of the shaft  130  is mounted onto the plate  110  by any types of mounting means such as welding, glue, threading, or the like. The length of the shaft  130  defined between the first end  132  and the second end  134  is preferably less than a distance between the bottom of a fireplace flue to be sealed and the floor of the fireplace. 
     The fireplace flue sealing device  100  also includes a tubular base  140  having a first end  142  and an opposite, second end  144  defining a base body portion  146  therebetween. The tubular base  140  is adapted for releasably receiving the shaft body portion  136  of the shaft  130  from the first end  142  of the tubular base  140 . As shown in  FIGS. 3 and 4 , he tubular base  140  has a first window  141  having a bottom edge  143  and a second window  145  having a bottom edge  147  formed oppositely on the tubular body portion  146  of the tubular base  140 . The bottom edge  143  of the first window  141  and the first end  142  define a first distance, H 1 , therebetween. The bottom edge  145  of the second window  145  and the first end  142  define a second distance, H 2 , therebetween, where H 2 &gt;H 1 . The length of the tubular base  140  defined between the first end  142  and the second end  144  is preferably less than a distance between the bottom of a fireplace flue to be sealed and the floor of the fireplace. 
     In one embodiment, the fireplace flue sealing device  100  further includes a cup  160  attached to the first end  142  of the tubular base  140 , the cup  160  defining a bore  162  adapted for releasably receiving the shaft body portion  136  of the shaft  130 . 
     Additionally, the fireplace flue sealing device  100  includes a locking mechanism  150  having a locking position, as shown in  FIG. 3 , and a releasing position, as shown in  FIG. 4 . The locking mechanism  150  is positioned in relation to the tubular base  140  and engaged with the shaft body portion  136  of the shaft  130  such that when the locking mechanism  150  is in the locking position, no motion of the shaft body portion  136  of the shaft  130  relative to the tubular base  140  is allowed, and when the locking mechanism  150  is in the releasing position, the shaft body portion  136  of the shaft  130  is movable back and forth relative to the tubular base  140 . 
     The locking mechanism  150  in one embodiment comprises a locking member  151  placed across the first window  141  and a second window  145  of the tubular base  140 , and a resilient spring  155  having a first end  156  and an opposite, second end  157  configured to be positioned inside the tubular base  140  such that the first end  156  and the second end  157  are in contact with the cup  160  and the locking member  152 , respectively. The locking member  151  defines a bore  152  that is adapted for releasably receiving the shaft body portion  136  of the shaft  130 . 
     In assembly, the second end  134  of the shaft  130  passes, in turn, through the bore  162  of the cup  160 , the resilient spring  155  of the locking mechanism  150 , and the bore  152  of the locking member  151  of the locking mechanism  150  such that the shaft body portion  136  of the shaft  130  is releasably received in the tubular body portion  146  of the tubular base  140 . 
     As shown in  FIG. 3 , when the resilient spring  155  is in its extended position, the extension force of the resilient spring  155  pushes the locking member  151  against the bottom edges  143  and  147  of the first and second windows  141  and  145  of the tubular base  140  and causes it to be tilted because H 2 &gt;H 1 , i.e., the bottom edges  143  and  147  of the first and second windows  141  and  145  of the tubular base  140  are not leveled. In the case, the shaft body  136  of the shaft  130  is in contact with the edge of the bore  152  of the locking member  151  and no motion of the shaft body portion  136  of the shaft  130  relative to the tubular base  140  is allowed. Accordingly, the locking mechanism  150  is in the locking position. 
     As shown in  FIG. 4 , the resilient spring  155  is in its retracted position, which can be achieved by applying a proper amount of a force  170  against the extension force of the resilient spring  155  to the locking member  151 . In the case, the locking member  151  is leveled so that the shaft body  136  of the shaft  130  is not in contact with the edge of the bore  152  of the locking member  151  and the shaft body portion  136  of the shaft  130  is freely movable relative to the tubular base  140 . Accordingly, the locking mechanism  150  is in the releasing position. 
     For such an arrangement of the present invention, the locking mechanism  150  is normally in the locking position. 
     The plate  110 , the shaft  130 , the tubular base  140  and the locking mechanism  150  are made of rigid materials. In one embodiment, the plate  110 , the shaft  130 , the tubular base  140  and the locking mechanism  150  are made of metals, plastic, wood and/or fiberglass. 
     The invented device  100  can be easily installed and removed with one hand holding the tubular base  140  and pushing the locking member  151 , and the other hand moving the plate  110  to a desired position. In installation, (a) placing the device  100  in a fireplace with the second end  144  of the tubular base  140  against the fireplace floor, (b) applying a sufficient amount of a force  170  to the locking member  151  of the locking mechanism  150  to cause the resilient spring  155  of the locking mechanism  150  to move from its extended position to its retracted position so that the locking mechanism  150  is in the releasing position, (b) moving/adjusting the shaft  130 , thus the plate  110  to a desired position so that the gasket  120  is substantially in contact with the bottom of the fireplace flue to provide sealing, and (d) releasing the applied force  170  from the locking member  151  of the locking mechanism  150 , thereby causing the resilient spring  155  of the locking mechanism  150  to move from its retracted position to its extended position so that the locking mechanism  150  is in the locking position. 
     Before using of the fireplace, the installed device  100  needs being removed from the fireplace. To do so, a force is applied to the locking member  151  of the locking mechanism  150  and causes to be in the releasing position, so that the gasket  120  and the plate  110  are detached from the bottom of the fireplace flue of the fireplace. 
     The foregoing description of the exemplary embodiments of the invention has been presented only for the purposes of illustration and description and is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations are possible in light of the above teaching. 
     The embodiments were chosen and described in order to explain the principles of the invention and their practical application so as to enable others skilled in the art to utilize the invention and various embodiments and with various modifications as are suited to the particular use contemplated. Alternative embodiments will become apparent to those skilled in the art to which the present invention pertains without departing from its spirit and scope. Accordingly, the scope of the present invention is defined by the appended claims rather than the foregoing description and the exemplary embodiments described therein.