FEDERALLY SPONSORED RESEARCH
Not Applicable
SEQUENCE LISTING OR PROGRAM
Not Applicable
BACKGROUND
Field
The application relates to the field of fittings for the terminal end of ventilating exhaust tubes or pipes including chimneys, stacks, roof vents, holding tank vents, radon gas vents, and other system vents; and to devices that utilize the wind to aid in the extraction of gases and mitigate the reverse flow of gases in exhaust conduits.
Prior Art
Vent systems commonly use pipes extending above building roofs to exhaust noxious or unwanted gasses thereby allowing the gases to be carried away by the wind. Often vent caps are used to keep rain and debris from entering the vent pipes. In addition some vent caps such as turbine ventilators use the wind to aid in the extraction of the vent gases.
Many exhaust systems that vent large amount of water vapor avoid the use of vent caps in order to minimize icing at the terminal end. These systems include wastewater drain vents and passive radon-reduction systems. These systems generally have the terminal end of the exhaust pipe terminated perpendicular to the pipe length. The wind blowing parallel over the top end of the pipe opening aids in extracting the gases. However the wind at rooftop levels is usually very turbulent making this method an unreliable way to extract gases. The October 2006 report “Effectiveness of Passive Radon-Reduction Systems in New Fort Collins Homes” documents this problem.
In the report, “Effectiveness of Passive Radon-Reduction Systems in New Fort Collins Homes”, it was shown that, on the average, the 65 new construction homes had a radon reduction of 49% (consistent with other similar studies), however nine of the homes (13.8%) had lower radon levels with the vents sealed compared to radon levels when the vents were open as designed.
The report concludes, “Testing of the 65 new Fort Collins homes shows an average radon reduction of 49% attributable to the installation of passive radon-reduction systems. However, 40% of the homes with a passive system have radon above 4 pCi/L, the USEPA-recommended action level. These 40% can easily activate their radon system by adding an in-line fan.”
It is therefore desired to provide wind powered extractors for the terminal end of the vent pipe of passive vent systems, such as radon-reduction systems. A wind powered gas extractor, utilizing turbulent airflow to reliably extract gases from the vent system, would eliminate the cost of purchasing, installing, and operating an in-line fan.
SUMMARY
A wind powered gas extractor with, with no moving parts, utilizing the kinetic energy of the wind to produce a lowered pressure area on a cone surface to draw exhaust gases from a central vent pipe opening.
DRAWINGS
In the drawings, illustrating various embodiments of the invention as vent termination fittings:
FIG. 1A is an exploded bottom perspective view of the first embodiment of the invention and the terminal end of a vent pipe.
FIG. 1B is a top perspective view of the first embodiment attached to the terminal end of the vent pipe.
FIG. 1C is a cross sectional view of FIG. 1BFIG. 1D illustrates downward airflow over the vent pipe and fitting of FIG. 1B.
FIG. 2A is a bottom perspective view of the second embodiment of the invention.
FIG. 2B is a cross sectional view of FIG. 2A.
FIG. 2C illustrates extreme downward airflow over the vent pipe and fittings of FIG. 2B.
FIG. 3 illustrates a bottom perspective view of a third embodiment of the invention that includes a rain cap.
FIG. 4 illustrates a side view of a forth embodiment of the invention that includes a debris cap.
DRAWINGS—REFERENCE NUMERALS
10 vent pipe
12 draft cone outer surface
14 mounting collar
15 draft cone fitting
- a1 draft cone angle
- d1 vent pipe inside diameter
- d2 vent pipe outside diameter, mounting collar inside diameter, and draft cone spacer's top section outside diameter
- d3 draft cone fitting lower large diameter.
20 two stage draft cone fitting assembly
22 draft cone spacer
24 top section (draft cone spacer)
26 flared section (draft cone spacer)
28 standoff mounts (draft cone spacer)
- d4 spacing distance
- d5 draft cone spacer bottom diameter
30 galvanized sheet metal vent pipe
32 draft cone outer surface
34 rain cap
35 galvanized sheet metal draft cone fitting
40 vent pipe
41 debris cap supports
42 draft cone outer surface
43 debris cap
44 convex surface
45 draft cone fitting with debris cap
DETAILED DESCRIPTION—FIGS. 1A THRU 1D—FIRST EMBODIMENT
The wind powered extractor in FIG. 1A (bottom perspective view) is illustrated as a single, injection molded, draft cone fitting 15 having a draft cone outer surface 12 and a mounting collar 14 for attachment to the terminal end of a plastic vent pipe 10.
FIG. 1B (top perspective view) illustrates the draft cone fitting 15 attached to the terminal end of the vent pipe 10. The top of the draft cone outer surface 12 is flush with the top on the vent pipe 10 sloping downward and away from the top of the vent pipe 10 whereby, gases flowing upward out of the vent pipe 10 are unrestricted.
FIG. 1C is a cross section view of FIG. 1B further illustrating the draft cone fitting 15 and the vent pipe 10. The vent pipe has an inside diameter d1 and an outside diameter d2. The mounting collar 14 has an inside diameter d2 equal to the vent pipe 10 outside diameter d2. The draft cone fitting 15 has an upper small diameter d2 (equal to the vent pipe's 10 outside diameter d2) and a lower large diameter d3. The lower large diameter d3 of the draft cone fitting 15, is three times larger than the upper small diameter d2. The draft cone outer surface 12 forms a truncated right circular cone having a slope angle a1 of 45 degrees.
OPERATION—FIG. 1D
FIG. 1D illustrates the vent pipe 10 with a draft cone fitting 15 exposes to a slightly downward airflow. The kinetic energy of the wind, as it is diverted by the draft cone outer surface 12, forms a low pressure area on the down wind side of the surface 12 creating an extraction force for the gases exiting the vent pipe 10. The draft cone outer surface 12 also forms a ramp on the upwind side of the vent pipe 10. The wind, diverted upward at the vent pipe 10 opening by the ramp effect, drags exhaust gas with it.
A draft cone fitting 15, with a with draft cone outer surface 12, of the size and angle describe above, has been shown to be an effective exhaust extractor in wind flows with a downward angle of up to 30 degrees.
DETAILED DESCRIPTION—FIGS. 2A THRU 2C—SECOND EMBODIMENT
FIG. 2A illustrates a wind powered extractor in the form of a two stage draft cone fitting assembly 20 attached to the terminal end of a vent pipe 10. The two stage draft cone fitting assembly 20 consisting of a lower draft cone fitting 15 and an upper draft cone fitting 15′ attached to the top of a draft cone spacer 22.
The draft cone spacer 22 has a flared section 26. The lower end of the flared section 26 having standoff mounts 28 attaching the draft cone spacer 22 to the lower draft cone fitting 15 such that the upper draft cone fitting 15′ is centered and directly above the lower draft cone fitting 15. The two stage draft cone fitting assembly 20 is attached to the vent pipe 10 at the top of the lower draft cone fitting 15.
FIG. 2B is a cross section view of FIG. 2A further illustrating the two stage draft cone fitting assembly 20 and vent pipe 10 showing the spacing of the two draft cone fittings 15, 15′ by the draft cone spacer 22.
The draft cone spacer 22, consisting of a top section 24 with an outside diameter d2, a flared section 26 with a bottom diameter d5, and a plurality of standoff mounts 28. The draft cone spacer 22 separates the upper draft cone fitting 15′ from the lower draft cone fitting 15 a spacing distance d4.
The draft cone spacer's 22 flared section's 26 bottom diameter d5 has a distance that is 1.75 times the distance of the draft cone spacer's 22 top section's 24 outside diameter d2. The spacing distance d4 is twice the distance of the outside diameter d2.
OPERATION—FIG. 2C
For vent systems, where any flow restrictions above the top of the vent pipe 10 are prohibited by code or unpractical the invention offers two advantages over a bare vent pipe with no terminal fitting. The first advantage is that the wind blowing horizontally over the top of a vent pipe 10 fitted with a draft cone fitting 15 provides a stronger extraction force than that of a bare terminal end of a vent pipe 10. The second advantage of the use of a draft cone fitting 15 is that reverse flows in the vent are mitigated when the wind is blowing downward.
FIG. 2C is a cross sectional view of the two stage draft cone fitting assembly 20 illustrating air flow when the wind is blowing at a steep downward angle. Within the two stage draft cone fitting assembly 20, when wind is blowing downward past the upper draft cone fitting 15′ and into the draft cone spacer 22, a venturi effect is created between the draft cone spacer 22 and the lower draft cone fitting 15 maintaining an extraction force at the top of the vent pipe 10 during steep downward gust. The two stage draft cone fitting assembly 20 has been shown to be an effective extractor in wind flows with a downward angle of up to 45 degrees.
ALTERNATIVE EMBODIMENTS—FIG. 3 AND FIG. 4
FIG. 3 and FIG. 4 illustrate draft cone fittings for uses where flow restrictions directly above the vent pipes 30, 40 are permitted and are practical. The fitting are made of materials compatible with the material of the vent pipes 30, 40 to which they are connected.
FIG. 3 Illustrates a galvanized sheet metal vent pipe 30 with a galvanized sheet metal draft cone fitting 35 including a rain cap 34 attached to the draft cone upper surface 32.
FIG. 4 illustrates a draft cone fitting 45, including a debris cap 43 attached to the draft cone upper surface 42, made of a material compatible with the material of the vent pipe 40. The debris cap 43 includes standoff supports 41 for attachment to and spacing from the draft cone upper surface. The debris cap 43 also includes a convex surface 44 with the convex side facing downward. The convex surface 44 is shaped to utilize the wind for an additional extracting force of the vent gases.
CONCLUSION, RAMIFICATION AND SCOPE
It can be seen that the wind draft cone fitting and its use in various wind draft cone fitting assemblies may provide an effective wind powered extractor for exhaust gases for a broad range of venting applications. Furthermore, the wind draft cone, and assemblies that incorporate them, provide additional advantages in that:
- There are no moving parts to wear or become unbalance;
- The bottom of the cone may be used for additional bracing without effecting performance;
- It can be manufactured using standard materials and methods;
- They may be used to retrofit existing systems;
- They operate with the wind from any direction.
The descriptions above contain specificities used to illustrate the embodiments but are not to be construed as limiting the scope of the embodiments. The scope of the embodiments should be determined by the appended claims and their legal equivalents.
Patent Application
20180266715
