TOP DISCHARGE ROOF VENTILATOR

• US 3,788,207 A
• Filed: 05/26/1972
• Issued: 01/29/1974
• Est. Priority Date: 05/26/1972
• Status: Expired due to Term

• Current Assignee: Lewis S. Doherty II
• Original Assignee: Lewis S. Doherty II
• Inventors: Doherty, Lewis S. II
• Primary Examiner(s): O'Dea, William F.
• Assistant Examiner(s): Ferguson, Peter D.
• Application Number:
  US05/257,148
• Time in Patent Office: 613 Days
• Field of Search: 98/42,43,66,74,59,79,116,85,119 137/533.21,533.29,543.23 415/157,158
• US Class Current: 454/362
• CPC Class Codes: F04D 25/14 and having shutters, e.g. automatically closed when not in use
• CPC Class Codes: Y10T 137/7915 Guide stem

Abstract

A roof ventilator for exhausting air includes a tapered, upstanding, hollow stack for sealed securement on a roof at an air opening therein. A hollow, upstanding and semispherical outlet bell is telescoped in close spaced radial relation over the upper end of the stack and has an open upper end. A substantially flat damper pan normally rests upon and closes the upper stack end. A mounting sleeve is fixedly supported within the stack. A hollow guide element, pendently and coaxially fixed to the damper pan, is slidably located within the mounting sleeve and carries limiting means coacting with the mounting sleeve for limiting movement of the damper pan upwardly off the upper stack end, whereby a pressure drop from the stack to the bell causes the damper pan to lift from the upper end of the stack to vent the stack into the bell.

Claims

1. A roof vent device for exhausting air, comprising in combination:

an upstanding hollow stack for mounting on a roof at a vent opening, said stack having open upper and lower ends;

a hollow upstanding outlet bell fixed with respect to said stack, said bell having an open lower end telescoped over the upper end of said stack and an open upper end, the diameter of said bell intermediate the ends thereof substantially exceeding the diameter of the ends thereof;

a damper pan normally closing the upper end of said stack and located within said bell;

means guiding said damper pan for substantially coaxial movement away from the stack in response to a pressure drop from said stack to said bell so as to exhaust air from said roof opening through said stack and bell.

2. The device of claim 1 in which said bell is substantially semispherical, having convexly outwardly curved sidewalls extending radially outwardly from said ends thereof toward the intermediate portion thereof, said stack being of upwardly tapered frustoconical form and extending for a minor portion of its length into the interior of said bell to a level below said intermediate bell portion, said guiding means including limit means limiting movement of said damper pan away from said stack to a level approximating the maximum diameter of said bell.

3. The device of claim 2 in which the diameter of said damper pan approximates that of the upper end of said stack, said damper pan having a dependent perimetral flange adapted to overhang said upper end of said stack and being disposed in close radially spaced relation to the exterior face of said stack for assisting in centering said damper pan on said stack as said damper pan is closed and preventing entry of foreign material into said stack when said damper pan is closed, said damper pan resting upon the upper end of said stack when closed.

4. The device of claim 3 in which the lower portion of the curved sidewall of the bell is spaced downwardly from and radially outwardly from said flange of said damper pan, said lower portion of said bell peripheral wall extending upwardly and outwardly in curved spaced relation past said flange for deflecting air passing between said damper pan and the upper end of said stack smoothly outwardly and upwardly through said open upper end of said bell.

5. The device of claim 4 in which the open lower end of said bell is fixed in radially outwardly spaced relation to said stack, whereby rain entering the upper bell end exits at the lower bell end along the outer face of said stack, the minimum spacing of said damper pan from the wall of said bell substantially exceeding the minimum spacing of said bell from said stack whereby to minimize air flow from said stack downwardly along the peripheral wall of said stack out of said bell.

6. The device of claim 1 in which the diameters of said damper pan and the open upper end of said top bell are approximately equal, the diameter of said bell intermediate its ends substantially exceeding the diameter of said damper pan for providing ample cross sectional area for relatively high volume and low velocity air flow in an annular zone between said damper pan and the peripheral wall of said bell.

7. The device of claim 6 in which the upwardly facing surface of said damper plate is substantially flat for preventing accumulation of rain water thereon, whereby said pressure drop is substantially uniform despite varying weather conditions.

8. The device of claim 1 in which said bell comprises a bowl-like lower bell portion and a bowl-like upper bell portion removably securable thereto by means including an overlApping flange, said overlapping flange being located substantially at the maximum diameter of said bell, said bell portions and stack being compactly nestable when disassembled, said stack and bell portions being dimensioned to allow inverted reception of said upper bell portion in said lower bell portion and inverted reception of said stack in said upper bell portion, said pan being nestable therewith.

9. The device of claim 1 wherein said means quiding said damper pan comprises a guide element coaxially fixed to and dependent from said damper pan, a hollow sleeve coaxially located within said stack adjacent the upper end thereof, arms fixed to the peripheral wall of said stack and extending inboard thereof, said arms fixedly carrying said sleeve therebetween, said arms and sleeve being spaced below and adjacent said damper pan when said damper pan rests upon the top of said stack.

10. The device of claim 9 in which the length of said guide element approximates the height of said stack, said guide element having means adjacent the lower end thereof for coacting with the lower end of said sleeve to limit upward movement of said damper pan to a height corresponding to the maximum diameter of said bell.

11. The device of claim 1 in which said stack is upwardly tapered and substantially frustoconical in form, said bell having a dependent flange at the open lower end thereof, said flange tapering in substantial parallelism to said stack and lying in close spaced relation thereto for defining an annular water drain opening therebetween for said bell, a plurality of fastening devices connecting said flange to said stack for supporting said bell, said fastening devices being distributed around the periphery of said stack, washerlike elements on said fastening devices disposed between said flange and said stack for maintaining said drain opening.

12. A roof vent device for exhausting air, comprising the combination:

an upstanding hollow stack adapted to be secured in sealed relation on a roof for venting an opening therethrough and having open upper and lower ends;

a hollow weather shield fixed with respect to said stack, said weather shield having an open lower end overhanging the upper end of said stack, an open upper end above said stack and a widened intermediate portion;

a damper pan normally closing the upper end of said stack and located within said weather shield;

means guiding said damper pan substantially coaxially upwardly from the stack to a full open position adjacent the widened intermediate portion of said weather shield in response to an increasing pressure drop from said stack to said weather shield, for maximizing exhaust air flow from said roof opening upwardly through said weather shield.