Abstract:
The present invention relates to a dripless chimney cap which prevents condensates from dripping down the outside of a chimney. The dripless chimney cap includes a cone-shaped top cap at the top of the chimney cap for stopping liquids and objects from falling into the chimney. A condensation drip pan in the shape of an inverted cone is positioned below the top cap and functions to catch and collect condensates, directing them toward the inside of the chimney flue. A mounting flange attaches to the chimney and secures the condensation drip pan and top cap to the chimney. A screen mesh located between the condensation drip pan and the mounting flange is designed to allow cross air flow.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   The present application claims priority to U.S. Provisional Patent Application No. 60/844,909, entitled “Dripless Chimney Cap”, filed on Sep. 16, 2006 by the same inventor, George W. Howard, the entirety of which is incorporated herein by reference. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a dripless chimney cap employed with or without a stainless steel chimney liner and top plate, in the protection of a chimney from the natural elements of the outside environment and naturally occurring condensation. 
   2. Discussion of Related Art 
   A chimney has an opening running its length for conveying exhaust gases from a fireplace, furnace or boiler acting as a heating source. Combustion products in the form of hot exhaust gases rise up the chimney to the outside. They are typically vertical to ensure that the hot gases flow smoothly upward. 
   The most common fuel sources for modern heating sources include natural gas, liquefied petroleum gas, fuel oil, coal and wood. 
   All of the above stated combustible sources when burned produce gases and other byproducts such as residue which flow upward within the chimney. 
   A chimney cap is typically located at the uppermost portion of a chimney to protect the chimney from the external natural elements such as precipitation. It also prevents animals and objects from getting into the chimney. They also act as a spark arrestor. 
   When the heat, gases and other byproducts flow upward within the chimney, the hot gases cool and create byproducts and residue on the underside of the chimney cap. These condensates drip down onto the top of the chimney and can cause staining, discolorization and corrosion of various materials. These condensates tend to drip out of the chimney cap and onto the outside of the chimney and the roof and walls of the house to which it is attached. 
   To make this a larger problem, dyes are added to heating oils during their production to differentiate them from diesel oil. These dyes condense out of the exhaust gases. Therefore the condensates can cause considerable staining, discolorization and corrosion. 
   Some prior art chimney caps are designed to have an open screen section to allow greater exhaust flow. Some of these are designed to allow the condensate to drip into the chimney opening in the absence of cross wind. However, with the pitch of the outer edge of the chimney cap sloping downward, outside the diameter of the chimney opening, the condensate continues to fall on the outside of the chimney opening, with or without a cross wind, causing staining, corrosion and discoloration. 
   Currently there is a need for a chimney cap system which prevents condensate dripping on the outside of the chimney and the house to which it is attached, so as to prevent staining, discolorization and corrosion of the chimney, even in windy conditions. 
   SUMMARY OF THE INVENTION 
   One embodiment of the present invention is a chimney cap [ 1100 ] mounted on an opening of the chimney which protects it from the penetrating external natural elements, while at the same time preventing the dripping of potentially staining condensates which occurs in the chimney as a result of combustion of suitable fuels in a heating source. The system comprises:
         a. a downward sloping surface being a top cap [ 1110 ] for stopping liquids and objects from falling into said chimney;   b. a condensation drip pan [ 1120 ] connected to the lower side of the top cap [ 1110 ], having a surface sloping downward toward the center of said chimney opening, functioning to collect condensates from the top cap [ 1110 ] and direct the condensates toward said center of said chimney opening;   c. mounting flange [ 1130 ] for attaching the condensation drip pan [ 1120 ] to said chimney.       

   OBJECTS OF THE INVENTION 
   It is an object of the present invention to provide a system which protects chimneys from the natural elements while preventing dripping of condensates from running down the outside of the chimney flues. 
   It is another object of the present invention to provide a chimney cap which protects against dripping of condensates and residue onto the outside of the chimney. 
   It is another object of the present invention to provide a system which, protects against the dispersion of potentially staining condensate that occurs as a result of horizontal wind gusts acting on the condensate. 
   It is another object of the present invention to provide a system which, though it is anchored to the chimney, can be removed from the chimney crown for maintenance purposes. 
   It is another object of the present invention to provide a system which is functional while maintaining aesthetic appeal. 
   It is another object of the present invention to provide a cap for a chimney which keeps the outside of the chimney clean. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The advantages of the instant disclosure will become more apparent when read with the specification and the drawings, wherein: 
       FIG. 1  is a side elevational view of one embodiment of a dripless chimney cap according to the present invention. 
       FIG. 2  is a side elevational, cut-away view of the embodiment of the dripless chimney cap shown in  FIG. 1 . 
       FIG. 3  is a top isometric view of one embodiment of the dripless chimney cap shown in  FIGS. 1-2 . 
       FIG. 4  is a top plan view of the embodiment of the dripless chimney cap shown in  FIGS. 1-3 . 
       FIG. 5  is bottom plan view of the embodiment of the dripless chimney cap shown in  FIGS. 1-4 . 
       FIG. 6  is a bottom isometric view of the embodiment of the dripless chimney cap shown in  FIGS. 1-5 . 
       FIG. 7  is a simplified block diagram illustrating one embodiment of a method of the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Heating sources such as fireplaces, furnaces and boilers employ a chimney to exhaust the combustion gases. Typically, chimney caps are incorporated to prevent precipitation, animals and objects from falling into the chimney. The problem with prior art chimney cap designs is that when exhaust gases condense as they cool, they collect as a condensate on the inside of the chinmey cap  1110 . The condensate typically drips down the outside of the chimney and house. 
   Ultimately, this dripping can produce aesthetically unwelcomed staining on the chimney cap, chimney and structure of which the chimney is contained within, which results in unappealing and unappreciated staining as well as costs and time spent on behalf of the owner of the chimney to remove the staining. The present invention prevents these problems while preserving the function of the chimney cap. This can be seen in the attached figures. 
     FIG. 1  is a side elevational view of one embodiment of a dripless chimney cap [ 1100 ]. 
     FIG. 2  is a side elevational, cut-away view of the embodiment of a dripless chimney cap [ 1100 ] shown in  FIG. 1 . 
   The present invention will be described in connection with  FIGS. 1 and 2 . 
   A chimney  10  coupled to a heating unit has an opening  20 . Typically, these chimneys  10  employ chimney liners  30 . Smoke and other combustion gases flow up liner  30  and out of chimney opening  20 . Many times, objects, rain and snow fall into chimney opening  20  weathering the chimney and heating unit at the bottom of liner  30 . 
   In the past chimney caps have been used; however, they typically allow condensate to run down the chimney  10  causing corrosion, discoloration and staining, weakening the chimney  10  and making it aesthetically unpleasing. 
   The present invention is directed toward reducing these problems. A dripless chimney cap  1100  according to the present invention is attached to the chimney liner  30  with a mounting flange  1130 . 
   The dripless chimney cap  1100  employs a top cap  1110  at the uppermost point of the chimney cap system  1100 , being a downwardly angled surface over the chimney opening. The top cap  1110  prevents rain, snow, animals and other objects from falling into the chimney opening. It also acts as a spark arrestor. 
   The top cap  1110  with a slightly larger diameter than the condensation drip pan  1120  is centered over condensation drip pan  1120 . The top cap  1110  and drip pan  1120  are secured together with spacers between them. This produces a gap between top cap  1110  and drip pan  1120  to form a continuous air vent  1140 . This allows gases trapped under top cap  1110  to escape. 
   The condensation drip pan  1120  has a surface which slopes downwardly toward the center of an opening  1180  of the mounting flange  1130 . Hot exhaust gases contact the lower side of top cap  1110  and condense. The condensate collects and drips downward onto drip pan  1120 . 
   Drip pan  1120  directs the condensate toward the center of mounting flange opening  1180  and down liner  30 . This prevents dripping of the condensate to the outside of chimney  10  reducing corrosion, discoloration and staining of the exterior of the chimney  10 . 
   A screen mesh  1160  may be used which fits between the mounting flange  1130  and the drip pan  1120 . This allows increased exhaust gas flow. If screen mesh  1160  is employed, an extension  1170  of drip pan  1120  is employed to direct the dripping condensate further to the center of the chimney opening  20  so that cross winds do not blow the condensate to drip to the outside of chimney opening  20 . 
   An optional flared lip  1150  may be employed which extends from and around the top side of mounting flange  1130 . It allows increased surface area to collect more condensate dripping from the chimney cap  1100 . In effect, this allows a bigger ‘net’ to catch the dripping condensate, especially if cross winds blow condensate onto screen mesh  1160 . 
   In  FIG. 2 , the extension  1170  of the drip pan  1120  is more clearly shown. It extends a distance marked “A” inwardly, toward the center of chimney opening  20 . The distance is selected to insure that condensate dripping downward affected by a cross wind of a defined maximum speed in the direction of the arrow marked “B” will still fall into mounting flange opening  1180 . The path of dripping condensate is marked “C”. 
   In order to further insure that the condensate drips within mounting flange opening  1180 , the flared lip  1150  is employed. 
   Mounting flange  1130  connects to the condensation drip pan  1120  and secures the chimney cap system to the chimney. 
     FIG. 3  is a top isometric view of one embodiment of a dripless chimney cap  1100  according to the present invention. All of the same parts have the same numbers as the other figures. 
   In this view, the dripless chimney cap [ 1100 ] is shown without the chimney  10  and liner  30 . The flared lip  1150  and the mounting flange opening  1180  are more visible from the viewpoint of this figure. 
     FIG. 4  is a top plan view of the embodiment of a dripless chimney cap shown in  FIGS. 1-3 . In this view the funnel shape of the optional flared lip  1150  can be seen. 
   Also it can be seen how pan extension  1170  has a smaller radius opening than flared lip  1150 . 
     FIG. 5  is bottom plan view of the embodiment of a dripless chimney cap shown in  FIGS. 1-4 . Here drip pan  1120  is plainly visible. Looking from the bottom, mounting flange  1130 , flare lip  1150  and screen mesh  1160  are shown going from inside to outside. 
     FIG. 6  is a bottom isometric view of the embodiment of a dripless chimney cap shown in  FIGS. 1-5 . 
   Also, the dripless chimney cap  1100  may be embodied without screen mesh  1160 . An air gap may be provided between drip pan  1120  and mounting flange  1130  to allow exhaust gases to exit. 
   Similarly, dripless chimney cap  1100  may be embodied without screen mesh  1160  and have a larger continuous air vent  1140  between the top cap  1110  and the drip pan  1120 . 
   Even though the chimney cap  1100  has been shown as having a round cross section, it may also be embodied with any number of cross sectional shapes including oval, square and rectangular cross sections. These have all been contemplated and are within the scope of the present invention. 
   The present invention may also be embodied as a method for reducing staining from condensates dripping down an outside surface of a chimney.  FIG. 7  is a simplified block diagram illustrating one embodiment of a method of the present invention. 
   The process starts at step  2001 . 
   In step  2003 , a top cap is provided over chimney opening. 
   The top cap has a surface which slopes downwardly and outwardly away from the chimney opening to a lip on its outermost extent. 
   In step  2005 , combustion gases from the chimney opening are allowed to impinge upon the underside surface of the top cap. The combustion gases condense into condensate which runs down the inner surface of the top cap. 
   In step  2007 , condensates are collected with a drip pan catching drippings of condensation from the top cap. 
   In step  2009 , the collected condensate is directed back into the chimney opening by the drip pan. The drip pan has a sloping surface which extends further outwardly than the top cap to catch the dripping from the top cap. The drip pan then slopes downwardly and inward extending over the chimney opening. The drip pan also has a center opening above the chimney opening. Therefore, the condensate runs down the sloping surface of the drip pan and falls through the center opening of the drip pan. 
   The condensate then falls into the chimney opening. 
   The process ends at step  2011 . 
   Although preferred embodiments have been described, other embodiments and modifications of the invention are intended to be covered by the spirit and scope of the present application.