US1957971A - Ventilator - Google Patents

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US1957971A
US1957971A US463402A US46340230A US1957971A US 1957971 A US1957971 A US 1957971A US 463402 A US463402 A US 463402A US 46340230 A US46340230 A US 46340230A US 1957971 A US1957971 A US 1957971A
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band
ventilator
head
cap
neck portion
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US463402A
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Perry S Martin
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23LSUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS IN GENERAL ; VALVES OR DAMPERS SPECIALLY ADAPTED FOR CONTROLLING AIR SUPPLY OR DRAUGHT IN COMBUSTION APPARATUS; INDUCING DRAUGHT IN COMBUSTION APPARATUS; TOPS FOR CHIMNEYS OR VENTILATING SHAFTS; TERMINALS FOR FLUES
    • F23L17/00Inducing draught; Tops for chimneys or ventilating shafts; Terminals for flues
    • F23L17/02Tops for chimneys or ventilating shafts; Terminals for flues
    • F23L17/10Tops for chimneys or ventilating shafts; Terminals for flues wherein the top moves as a whole

Definitions

  • This invention relates to ventilators, and has reference, more particularly, to what are ordinarily known as roof ventilators, or ventilator heads.
  • I aim to minimize the effect of back pressureupon free exhausting of the air from the building with which the ventilator is used and at the same time preclude entry of rain, snow or sleet.
  • Another aim of my invention is to secure the maximum aspirating effect from the wind passing over the top of the ventilator, through exclusion of wind currents deflected upward by the roof of the building such as would interfere with efilcient functioning of the ventilator.
  • a further aim of my invention is to attain the above indicated desideratum in a roof ventilator which is simple in construction, inexpensive, and
  • Fig. I shows a plan view of my improved ventilator head with a portion thereof broken out to expose important details at the interior.
  • Fig. II is an axial sectional view of the ventilator head taken as indicated by the arrows IIII in Fig. I.
  • Fig. III is a side view of a baffle cap which con- ;stitutes a part of the ventilator head; while Figs. IV, V and VI are perspective views showing various details of the bafiie cap.
  • the ventilator head of my invention comprises a tubular neck portion which is adapted to be inserted into an opening through the roof of a building which is to be ventilated.
  • This tubular neck portion 10 is surmounted by a comparatively deep cylindric band 11 of larger diameter which, as shown in Fig. II, laps the upper edge of said neck portion by a slight margin with provision thereabout of a wide circumferential outlet space 12.
  • the band 11 is supported by a number of circumferentially arranged brackets 13 having downward and upward extremities 14, 15 at opposite ends of their radial arms 16, said extremities being secured respectively to the neck portion and to the band by screw bolts 17, 18.
  • baffle cap 20 Axially disposed within the upper part of the band 11, at a level above the top edge of the neck portion 10, is a baffle cap which is comprehensively designated by the numeral 20.
  • This baffie cap is of conical configuration and of com posite construction for penetrability by the exhaust air released from the ventilator head.
  • the cap 20 comprises a pair of correspondingly dished center pieces 21, 22 which are relegated to different planes through interposition between them of a co-axial collar 23, see Figs. II and VI, and held assembled with the collar by means of an axial screw bolt 24.
  • radial segments 27, 28 Attached respectively to the under and upper faces of the sloping flanges of the centerpieces 21, 22 by screw bolts 25, 26, are radial segments 27, 28 which are individually fashioned from sheet metal to channel cross section. Referring to Figs. II and III it will be observed that the segments 27, 28 are alternatingly arranged and overlap one another with their side flanges opposing. To assist assembling and to predetermine proper radial disposal of the segments 2'7, 28, the center pieces 21, 22 are respectively provided with lugs 29, 30 between which the inner ends of said segments engage as clearly shown in Figs. IV and V. From Figs.
  • the baffle cap 20 is provided withelongated protected openings 3'? through which a portion of the upward exhaust flow from the building is released from the head, as later on more fully explained.
  • the baffle cap 20 is supported within the band 11 by means of brackets 40 which are secured to the inside of said band at circumferential intervals in correspondence with the allocation of the brackets 13, said brackets 40 having inwardly extending radial arms 41 which are pierced at their ends for passage of screws 42 that take into the upper center piece 21 of said bafiie.
  • the baffle cap 20 is surrounded by a supplemental inner band 43 having a vertical depth to reach from the level of the upper edge of the outer band 11 down to the level of the outer ends of the upper series of radial segments 27, with formation of an annular out-flow clearance 44 at the top of the ventilator head in line with the annular bottom outlet space 12 aforementioned.
  • the supplemental band 43 is supported by angle spacers 45 whereof the outer flanges engage behind the vertical legs of the brackets 40 that support the cover bave 20, screws 40a serving as a common means for securing the brackets 40 and spacers 45 to the band 11.
  • the neck portion 10 of the ventilator head is surrounded by a downwardly divergent conical guard 46 whereof the periphery is co-extensive with that of the band 11.
  • This conical guard 46 is supported by drop arms 47 depending from the radial arms 16 of the brackets 13.
  • the air to be exhausted from the building upon entering the ventilator head via; the tubular neck portionlO, diffuses in all di; rections in seeking the several channels open for its escape.
  • part of the upward flow in impinging upon the bafile cap 20, subdivides and finds its way out through the protected radial openings 3'7 between the interlapping channelled segments 27, 28 of said cap, after the manner indicated by the arrows in Figs. I and III.
  • Another part of the upward flow of air passes direct into the external atmosphere through the annular outlet interval 44 between the outer band 11 and the supplemental inner band 43 at the top of the ventilator head.
  • the baffle cap 20 operates to check back draft under the influence of downward outside air pressure, and, moreover, to prevent rail, snow and sleet from falling into the top of the neck 10 by diverting it for discharge through the bottom outlet space 12 of the ventilator head.
  • the supplemental band 43 acts as a means to prevent entry of driving rain, sleet and snow into the neck 10 of the ventilator at an angle.
  • the exhausting action of the ventilator is obviously promoted through aspiration induced by movement of the wind crosswise of the annular top outlet clearance 44; and the efficiency of the ventilator is materially increased by action of the downwardly flared guard 46 which prevents currents of air, deflected upward by the roof of the building, from entering the ventilator head at the bottom and checking or nullifying the aspiratory action induced in the manner just explained.
  • a ventilator head having a tubular neck portion; a comparatively deep superimposed coraxial band of larger diameter vertically lapping the upper edge of the neck portion by a slight margin with provision thereabout of a circumferential space constituting a bottom exhaust outlet; and a conical rain-deflecting bafllecap axially within the top of the band, said cap including spaced channel-section segments alternately overlapping to define radial-outlets for escapeof part of the upward exhaust flow from the head.
  • a ventilator head having a tubular neck'portion; a comparatively deep superimposed co-iaxial band of larger diameter vertically'l'apping the'upper edge of a neck portion by a slight margin with provision thereabout of a circumferential space constituting a bottom exhaust outlet; and a rain deflecting baflle cap axially within the top of the band having protected radially-arranged elongated openings to permit escape of upward exhaust flow from the head.
  • a ventilator head having a tubular neck portionya comparatively deep superimposed co-axial band of larger diameter vertically lapping the upper edge of the neck portion by a slight margin with provision thereabout of a circumferential space constituting a bottom exhaust outlet; and a rain deflecting bafiie cap axially within the top of the band, said bafile cap consisting of a number "of radial segments of channel section defining side flanges, said segments being arranged in spaced planes with the side flanges opposing an'd one overlapping the other with incident formation of protected elongated openings permitting escape of the upward exhaust flow from the head.
  • a ventilator head having a tubular neck portion; a comparatively deep superimposed cylindric band of larger diameter vertically lapping the upper edge of a neck portion by a slight margin with provision thereabout of a circumferential space constituting a bottom exhaust outlet; and a rain-deflecting bafile cap axially within the upper portion of the band comprising a pair of iozi center pieces and alternatingly arranged radial segments of channel cross section defining side flanges, said radial segments being supported in vertically spaced relation by the center pieces with the side flanges interlapping to form-protected elongated openings for escape of I upward exhaust flow from the head.
  • a ventilator head having a tubular neck portion; a comparatively deep superimposed co'-axial band of larger diameter vertically lapping the u'p per edge of the neck portion by a slight margin with provision thereabout of a circumferential space constituting a bottom exhaust outlet, and a 'conical'rain deflecting bafiie cap axially within the top of the band, said cap including vertically-E20 spaced 'cha'nnel section segments alternately overlapping with their side flanges opposing to define radial-outlets permitting escape of part of the upward exhaust flowfrom the head, said b attle cap having 'a'n area greater than that of the neck portion but somewhat less than t hat of the band with provision of an outlet clearance for upward annular escape of exhaust air at the 'top of the head.
  • a ventilator liea'd having atub'ul'arneck pertio'n a comparatively deep superimposed co-axial band of larger diameter vertically lapping the upper'edge of the neck p'or't'ion by a slight margin with provision thereabout of a wide circumferential space constituting a bottom exhaust outlet; a rain deflecting baffle 'cap axially within tirefupper portion of the band havingprotect'ed elongated openings'defined by and lower alternatin'gly arranged'channel ⁇ section radial segments for upward exhaustfiow releasedthrfough thehead, said:
  • cap having an 'areasomewhat less than that of the band with formation of an annulanexhaust clearance at the 'top of the head; and asupplemental inner band reaching fiomthe level bf "the 7 upper edgeof the'oliter'bandtofthe outerends of the upper series of radial segments to roman conjunction with the outer bandgan'annular exhaust outlet clearanceat the t'e'pof'the h'ead,said supplemental band also serving as;a guard -to-arrest driving'rainfsleet or'snow'eriterin'g theannular clearance aforesaid and prevent it from falling into the neck portion.
  • a ventilator head having a tubular neck portion; a comparatively deep superimposed co-axial band of larger diameter vertically lapping the upper edge of the neck portion by a slight margin with provision thereabout of a circumferential space constituting a bottom exhaust outlet; a rain deflecting baffle cap axially within the top of the band, said cap having protected radial openings defining vertical-diffusive escape of part of the upward exhaust flow from the head and being of an area somewhat less than that of the

Description

y 1934- P. s. MARTIN 1,957,971
7 VENTILATOR Filed June 24, 1930 2 Sheets-Sheet l 1T llllllilllil WITNESSES L al i Mariam,
TTORNEYS.
I INVENTOR:
P. 5. MARTIN May 8, 1934.
VENT I LATOR Filed June 24, 1930 2 Sheets-Sheet 2 INVENTOR: ,Pezrgf ,SZ Mariya TTORNEYS.
Patented May '8, 1934 osri VENTILATOR Perry S. Martin,
Harrisonburg, Va.
Application June 24, 1930, Serial No. 463,402
'7 Claims.
This invention relates to ventilators, and has reference, more particularly, to what are ordinarily known as roof ventilators, or ventilator heads.
In connection with a ventilator of the type referred to, I aim to minimize the effect of back pressureupon free exhausting of the air from the building with which the ventilator is used and at the same time preclude entry of rain, snow or sleet.
Another aim of my invention is to secure the maximum aspirating effect from the wind passing over the top of the ventilator, through exclusion of wind currents deflected upward by the roof of the building such as would interfere with efilcient functioning of the ventilator.
A further aim of my invention is to attain the above indicated desideratum in a roof ventilator which is simple in construction, inexpensive, and
highly eificient as well as reliable in use under all weather conditions.
Other objects and attendant advantages of this invention will be manifest from the detailed description following taken in connection with the attached drawings, wherein Fig. I shows a plan view of my improved ventilator head with a portion thereof broken out to expose important details at the interior.
Fig. II is an axial sectional view of the ventilator head taken as indicated by the arrows IIII in Fig. I.
Fig. III is a side view of a baffle cap which con- ;stitutes a part of the ventilator head; while Figs. IV, V and VI are perspective views showing various details of the bafiie cap.
As herein delineated, the ventilator head of my invention comprises a tubular neck portion which is adapted to be inserted into an opening through the roof of a building which is to be ventilated. This tubular neck portion 10 is surmounted by a comparatively deep cylindric band 11 of larger diameter which, as shown in Fig. II, laps the upper edge of said neck portion by a slight margin with provision thereabout of a wide circumferential outlet space 12. The band 11 is supported by a number of circumferentially arranged brackets 13 having downward and upward extremities 14, 15 at opposite ends of their radial arms 16, said extremities being secured respectively to the neck portion and to the band by screw bolts 17, 18.
Axially disposed within the upper part of the band 11, at a level above the top edge of the neck portion 10, is a baffle cap which is comprehensively designated by the numeral 20. This baffie cap is of conical configuration and of com posite construction for penetrability by the exhaust air released from the ventilator head. As shown, the cap 20 comprises a pair of correspondingly dished center pieces 21, 22 which are relegated to different planes through interposition between them of a co-axial collar 23, see Figs. II and VI, and held assembled with the collar by means of an axial screw bolt 24. Attached respectively to the under and upper faces of the sloping flanges of the centerpieces 21, 22 by screw bolts 25, 26, are radial segments 27, 28 which are individually fashioned from sheet metal to channel cross section. Referring to Figs. II and III it will be observed that the segments 27, 28 are alternatingly arranged and overlap one another with their side flanges opposing. To assist assembling and to predetermine proper radial disposal of the segments 2'7, 28, the center pieces 21, 22 are respectively provided with lugs 29, 30 between which the inner ends of said segments engage as clearly shown in Figs. IV and V. From Figs. IV and V it will be particularly noted that the inner ends of the side flanges of the radial segments 2'7, 28 are bent over as at 31, 32 to engage behind the lugs 29, 30 of the inner circles, this provision being for greater security of said segments against displacement, Proper registry as between the radial segments 27, 28 of the cap 20 is insured by radial lugs 33, 34 respectively on the underside of the top center piece 21 and on the upper side of the lower center piece 22 arranged to engage aligned notches 35, 36 in the top and bottom edges of the spacing collar 23.
In this way, the baffle cap 20 is provided withelongated protected openings 3'? through which a portion of the upward exhaust flow from the building is released from the head, as later on more fully explained. The baffle cap 20 is supported within the band 11 by means of brackets 40 which are secured to the inside of said band at circumferential intervals in correspondence with the allocation of the brackets 13, said brackets 40 having inwardly extending radial arms 41 which are pierced at their ends for passage of screws 42 that take into the upper center piece 21 of said bafiie.
Referring to Figs. I and II, the baffle cap 20 is surrounded by a supplemental inner band 43 having a vertical depth to reach from the level of the upper edge of the outer band 11 down to the level of the outer ends of the upper series of radial segments 27, with formation of an annular out-flow clearance 44 at the top of the ventilator head in line with the annular bottom outlet space 12 aforementioned. As shown in Figs. I and II, the supplemental band 43 is supported by angle spacers 45 whereof the outer flanges engage behind the vertical legs of the brackets 40 that support the cover baiile 20, screws 40a serving as a common means for securing the brackets 40 and spacers 45 to the band 11. At a level beneath the lower edge of the supplemental band 45, the neck portion 10 of the ventilator head is surrounded by a downwardly divergent conical guard 46 whereof the periphery is co-extensive with that of the band 11. This conical guard 46 is supported by drop arms 47 depending from the radial arms 16 of the brackets 13.
In operation, the air to be exhausted from the building, upon entering the ventilator head via; the tubular neck portionlO, diffuses in all di; rections in seeking the several channels open for its escape. As shown by the arrows in Fig II, part of the upward flow, in impinging upon the bafile cap 20, subdivides and finds its way out through the protected radial openings 3'7 between the interlapping channelled segments 27, 28 of said cap, after the manner indicated by the arrows in Figs. I and III. Another part of the upward flow of air passes direct into the external atmosphere through the annular outlet interval 44 between the outer band 11 and the supplemental inner band 43 at the top of the ventilator head. The remainder of the air flows over the top edge of the neck portion 10 and out through the broad annular outlet space 12 between said neck portion and the bottom edge of the outer band 11. It will thus be seen, that, by virtue of the small amount of resistance imposed in my novel ventilator head, ordinarily the outflowing air is substantially free of restraint and therefore free to respond to natural or draft action. In addition to functioning as above described, the baffle cap 20 operates to check back draft under the influence of downward outside air pressure, and, moreover, to prevent rail, snow and sleet from falling into the top of the neck 10 by diverting it for discharge through the bottom outlet space 12 of the ventilator head. In cooperation with the band 11 and the baffle cap 20, the supplemental band 43 acts as a means to prevent entry of driving rain, sleet and snow into the neck 10 of the ventilator at an angle. The exhausting action of the ventilator is obviously promoted through aspiration induced by movement of the wind crosswise of the annular top outlet clearance 44; and the efficiency of the ventilator is materially increased by action of the downwardly flared guard 46 which prevents currents of air, deflected upward by the roof of the building, from entering the ventilator head at the bottom and checking or nullifying the aspiratory action induced in the manner just explained.
Having thus described my invention, claim:
1. A ventilator head having a tubular neck portion; a comparatively deep superimposed coraxial band of larger diameter vertically lapping the upper edge of the neck portion by a slight margin with provision thereabout of a circumferential space constituting a bottom exhaust outlet; and a conical rain-deflecting bafllecap axially within the top of the band, said cap including spaced channel-section segments alternately overlapping to define radial-outlets for escapeof part of the upward exhaust flow from the head.
2. A ventilator head having a tubular neck'portion; a comparatively deep superimposed co-iaxial band of larger diameter vertically'l'apping the'upper edge of a neck portion by a slight margin with provision thereabout of a circumferential space constituting a bottom exhaust outlet; and a rain deflecting baflle cap axially within the top of the band having protected radially-arranged elongated openings to permit escape of upward exhaust flow from the head.
3. A ventilator head having a tubular neck portionya comparatively deep superimposed co-axial band of larger diameter vertically lapping the upper edge of the neck portion by a slight margin with provision thereabout of a circumferential space constituting a bottom exhaust outlet; and a rain deflecting bafiie cap axially within the top of the band, said bafile cap consisting of a number "of radial segments of channel section defining side flanges, said segments being arranged in spaced planes with the side flanges opposing an'd one overlapping the other with incident formation of protected elongated openings permitting escape of the upward exhaust flow from the head.
4. A ventilator head having a tubular neck portion; a comparatively deep superimposed cylindric band of larger diameter vertically lapping the upper edge of a neck portion by a slight margin with provision thereabout of a circumferential space constituting a bottom exhaust outlet; and a rain-deflecting bafile cap axially within the upper portion of the band comprising a pair of iozi center pieces and alternatingly arranged radial segments of channel cross section defining side flanges, said radial segments being supported in vertically spaced relation by the center pieces with the side flanges interlapping to form-protected elongated openings for escape of I upward exhaust flow from the head.
5. A ventilator head having a tubular neck portion; a comparatively deep superimposed co'-axial band of larger diameter vertically lapping the u'p per edge of the neck portion by a slight margin with provision thereabout of a circumferential space constituting a bottom exhaust outlet, and a 'conical'rain deflecting bafiie cap axially within the top of the band, said cap including vertically-E20 spaced 'cha'nnel section segments alternately overlapping with their side flanges opposing to define radial-outlets permitting escape of part of the upward exhaust flowfrom the head, said b aiile cap having 'a'n area greater than that of the neck portion but somewhat less than t hat of the band with provision of an outlet clearance for upward annular escape of exhaust air at the 'top of the head. v
6. A ventilator liea'd having atub'ul'arneck pertio'n a comparatively deep superimposed co-axial band of larger diameter vertically lapping the upper'edge of the neck p'or't'ion by a slight margin with provision thereabout of a wide circumferential space constituting a bottom exhaust outlet; a rain deflecting baffle 'cap axially within tirefupper portion of the band havingprotect'ed elongated openings'defined by and lower alternatin'gly arranged'channel{section radial segments for upward exhaustfiow releasedthrfough thehead, said:
cap "having an 'areasomewhat less than that of the band with formation of an annulanexhaust clearance at the 'top of the head; and asupplemental inner band reaching fiomthe level bf "the 7 upper edgeof the'oliter'bandtofthe outerends of the upper series of radial segments to roman conjunction with the outer bandgan'annular exhaust outlet clearanceat the t'e'pof'the h'ead,said supplemental band also serving as;a guard -to-arrest driving'rainfsleet or'snow'eriterin'g theannular clearance aforesaid and prevent it from falling into the neck portion.
'7. A ventilator head having a tubular neck portion; a comparatively deep superimposed co-axial band of larger diameter vertically lapping the upper edge of the neck portion by a slight margin with provision thereabout of a circumferential space constituting a bottom exhaust outlet; a rain deflecting baffle cap axially within the top of the band, said cap having protected radial openings defining vertical-diffusive escape of part of the upward exhaust flow from the head and being of an area somewhat less than that of the
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3309979A (en) * 1964-12-21 1967-03-21 Charles K Razak Ventilating device
US4147096A (en) * 1977-06-01 1979-04-03 Dresser Industries, Inc. Breather vent for vapor vent valve
US20110171898A1 (en) * 2008-09-18 2011-07-14 Berling Gmbh Exhaust Hood
US20150090246A1 (en) * 2013-10-01 2015-04-02 International Clean Energy Solutions, Ltd. Cooking stove

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3309979A (en) * 1964-12-21 1967-03-21 Charles K Razak Ventilating device
US4147096A (en) * 1977-06-01 1979-04-03 Dresser Industries, Inc. Breather vent for vapor vent valve
US20110171898A1 (en) * 2008-09-18 2011-07-14 Berling Gmbh Exhaust Hood
US20150090246A1 (en) * 2013-10-01 2015-04-02 International Clean Energy Solutions, Ltd. Cooking stove
US9506656B2 (en) * 2013-10-01 2016-11-29 International Clean Energy Solutions, Ltd. Cooking stove
US10077898B2 (en) 2013-10-01 2018-09-18 International Clean Energy Solutions, Ltd. Combustion engine for burning a fuel mixture of water and alcohol

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