US3053165A - Upward discharge ventilators - Google Patents

Upward discharge ventilators Download PDF

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US3053165A
US3053165A US846740A US84674059A US3053165A US 3053165 A US3053165 A US 3053165A US 846740 A US846740 A US 846740A US 84674059 A US84674059 A US 84674059A US 3053165 A US3053165 A US 3053165A
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cowl
discharge
cowling
air
deflector
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US846740A
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Rampley Kenneth
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COLT VENTILATION Ltd
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COLT VENTILATION Ltd
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F7/00Ventilation
    • F24F7/02Roof ventilation
    • F24F7/025Roof ventilation with forced air circulation by means of a built-in ventilator

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  • a direct upward discharge from a forced draught ventilator would obviate the disadvantages indicated, but in order to afford a weather protection this has not hitherto been feasible, as the general practice is to cover a roof ventilator in such a manner as to provide effective weather protection, and against the ingress f rain, the result being that the discharge from the unit is directed downwardly.
  • the object of the present invention is to obviate the aforesaid disadvantages.
  • Upward discharges ventilators have hitherto embodied flaps which open upwards when the fan is operating and close to provide weather protection at other times.
  • an upward discharge ventilator comprises a cowling, a base inlet below which an exhaust fan is mounted and a top outlet to provide an upwardly directed discharge, a deflector mounted in said cowling and presenting a deflecting face or faces to said outlet, whereby a circuitous passage is formed within the cowling from inlet to outlet, said deflector forming a cover for said inlet and passages from said cowling for drainage purposes.
  • the upward discharge ventilator may be of rectangular or circular form in plan with rectangular and circular inlets and outlets respectively, the deflector with a circular construction being substantially of conical form.
  • Dampers may be fitted at the entry of the circuitous passage between the deflector and inlet, and the said dampers may be electrically or mechanically or gravity controlled.
  • circuitous passage may have fitted therein splitters shaped to the natural flow line, imparted to the air being exhausted.
  • FIGURE 1 is a perspective view of a forced draught extraction ventilation unit according to the invention.
  • FIGURE 2 illustrates diagrammatically in cross-section an extraction unit as illustrated in FIGURE 1.
  • FIGURE 3 is an end elevation of FIGURE 2
  • FIGURE 4 illustrates a detail
  • FIGURE 5 is a similar view to FIGURE 2 illustrating a modified form of the invention.
  • FIGURE 6 is a side elevation of FIGURE 5 and FIGURE 7 is a perspective view of the cowl shown in FIGURE 5.
  • FIGURE 8 is a diagrammatic sectional elevation of a forced draught ventilator according to the present invention.
  • FIGURE 9 is a part sectional plan of FIGURE 1.
  • a forced draught upward extraction unit for ventilation purposes comprising a cowling 5 of rectangular form in plan, and consisting of two end plates 6 and 7 and side walls 8 and 9, the two latter walls being of semi-circular crosssection and fixed to the side walls in accordance with accepted practice.
  • the cowl 5 has a rectangular shaped air outlet 10 at the top, extending the full width of the cowl and a similar shaped air inlet passage 11 at the base.
  • the inlet passage 11 has a flanged base 12, by means of which it is secured in place on a roof.
  • the cowl 5 houses a deflector or shroud 13, which extends lengthwise between the walls 6 and 7 of the cowl and presents a convex surface 14 to the inlet 11 and concave surfaces 15, 15 to the outlet 10.
  • the convex surface 14 marries into the concave surfaces 15, 15 at beaded edges 14a.
  • Shutters or dampers 16, 17 which also extend across the cowl between the walls 6 and 7 are hinged to the base of the deflector 13 as at Ma and 17a and are motor or gravity operated so as to prevent all air flow except when an exhaust fan such as 18 is in operation, suitable automatically controlled switch gear may be provided.
  • splitters 159 and 20 which conform in shape to the expected flow path the air exhausted will take during operation of the exhaust fan 18.
  • the splitters 19 and 20 serve to straighten the air flow and maintain performance.
  • drain outlets 21, 22 are provided in the walls 6 and 7 for escape purposes.
  • a longitudinal gap 23 (see FIGURE 4) is provided between the side walls 9 and the outlet passage 11 so that water accumulating at the base of the cowl will flow away to the roof of the building. It is also desirable to hinge the cowl along one side as at 24, so that access can be had to the exhaust fan 18 if necessary.
  • FIGURES 5, 6 and 7 show a modified form of ventilator similar in many respects to the cowl illustrated in FIGURES l to 4, the same reference numerals have been used for corresponding parts of both forms of ventilator.
  • the major dilferences of the modified form of cowl consist in the provision of a larger air outlet 10 and that the deflector 13 is of reduced height and the convex surface 14 has a greater radius and extends as a continuous surface from the lines of joindure 14a with the deflector 13.
  • gravity type dampers may be embodied which open automatically upon the uprush of air from the ventilator fan, the motor 18 of which is now housed within the inlet passage 11.
  • the modified form of construction according to FIG- URES 5 to 7 results in that practically the whole of the top of the ventilator is open and the total height is considerably reduced whereby resistance is decreased.
  • the cowl is completely waterproof when the fan is running or not.
  • the gravity operated dampers 16, 17 when in the closed position prevent ingress or egress of air at times when such is not wanted.
  • forced draught upward extraction unit is illustrated of circular form in plan and comprising a cowl 25 of hollow ring form providing a convex outer surface 26 and a concave inner surface 27.
  • the cowling is removable mounted on a base 28 adapted to fixing to the roof of a building, the base housing the usual motor driven exhaust fan 13 as previously described.
  • the deflector is connected to the cowl by radial stays 35.
  • dampers 36 pivoted to a support 37 and are weighted so as to close by gravity when the uprush of air from the fan 18 ceases.
  • the circular form of cowl embodies the major features of the rectangular form of cowl and those features which have not been specifically described for example the splitters 20 may be installed in the cowl between the deflector and the inner wall thereof and conform in shape to the flow of the air exhausted.
  • the forced draught ventilation units according to the invention are preferably produced from light aluminium alloy or other suitable material; the cowling imparts an upward direction to exhaust air, and is permanently weatherproof regardless of operation of the fan or other moving parts.
  • the unit is intended to lie on the plane of a roof and requires no adjustment to suit different roof angles.
  • the cowl can be allowed to act as a natural exhaust ventilator.
  • the cowl is hinged to open externally to give free access to the installation, removal, or maintenance of fan and motor.
  • the construction due to the shape has a low resistance to air flow.
  • the motor operated shutters 16, 17 of the construction shown in FIGURES 1 to 4 prevent all air-flow except when the fan 18 is operating, in contrast to the gravity closing dampers which float open in the airstream, as embodied in the construction according to FIGURES to 6.
  • An upward discharge ventilator unit comprising a cowling rectangular in plan with a pair of end plates and a pair of semi-circular side walls presenting a rec tangular air outlet at the top extending the full width of the cowling between the side walls, a base with base walls on which said cowling is mounted and having an air inlet passage communicating with the interior of the cowling, an exhaust fan mounted in the air inlet passage and an air outlet passage in the top of the cowling to provide an upwardly directed discharge, a deflector mounted lengthwise in the cowling between the cowling end plates and having upwardly inclined concave surfaces meeting in a ridge at the top opening and a bottom convex wall to the outer edges of which the lower edges of said surfaces are secured, said outer edges extending into the side walls beyond the edges of the inlet and outlet openings, there being a gap between the base walls and the lower edges of the side walls, and draining passages in said end walls positioned at the lower ends of said upwardly inclined concave surfaces, whereby a circuitous passage is formed within the
  • An upward discharge ventilator according to claim 1 wherein the cowling has a concave inner wall surface and is of rectangular form in plan with rectangularly shaped inlet and outlet.
  • An upward discharge ventilator according to claim 1 wherein splitters, shaped to the natural flow line, imparted to the air being exhausted are fitted Within the circuitous passage.
  • the cowling is of hollow ring form providing a convex outer surface and a concave inner surface, an upper circular discharge outlet and a lower circular base inlet, the deflector being circular presenting a convex base to the inlet and an apex to the discharge outlet, the apex being the peak of a substantially conically shaped member whose walls curve sinuously in section to the perimeter of the deflector where it is united with the convex base and forms with the inner cowl wall a curvilinear passage.

Description

Sept. 11, 1962 K. RAMPLEY 3,053,165
UPWARD DISCHARGE VENTILATORS Filed Oct. 15, 1959 I 5 Sheets-Sheet 1 Sept. 11, 1962 K. RAMPLEY 3,053,165
UPWARD DISCHARGE VENTILATORS Filed Oct. 15, 1959 5 Sheets-Sheet 2 dim 84 A. vi Sept. 11, 1962 K. RAMPLEY 3,053,165
UPWARD DISCHARGE VENTILATORS Filed Oct. 15, 1959 5 Sheets-Sheet 3 Sept. 11, 1962 Filed Oct. 15. 1959 K. RAMPLEY UPWARD DISCHARGE VENTILATORS 5 Sheets-Sheet 5 Patented Sept. 11, 1962 3,053,165 UPWARD DISCHARGE VENTILA'IORS Kenneth Rampley, Woking, England, assignor to Colt Ventilation Limited, Surbiton, Surrey, England, a company of Great Britain and Northern Ireland Filed Oct. 15, 1959, Ser. No. 846,740 Claims priority, application Great Britain Oct. 28, 1959 6 Claims. (Cl. 8-43) This invention relates to upward discharge ventilators especially intended as roof extraction units.
Forced upward draught roof extraction units have hitherto embodied to a very large extent a downward discharge cowl, and are used considerably for ventillation of factories. One of the disadvantages of such units is that the exhausted air may contain products harmful to roof covering, and to gutters and drains, when swilled down by rain. Such products include dusts causing obstruction of gutters and drains, as Well as corrosive products.
Where exhaust products are not actually harmful, they can still cause unsightly soiling of the roof near a downward discharge cowl. Further, exhaust air from a downward discharge cowl can taint air close to the roof as much as 50 feet away, and so complicate the use of Intake Units, where air drawn in is liable to contamination. Downward discharge cowls can provide extra resistance to flow and thus additional load on the fan.
Upward discharge type cowls have been proposed but as they rely entirely on dampers for weathering, no other protection being provided, they have not proved very satisfactory in practice.
A direct upward discharge from a forced draught ventilator would obviate the disadvantages indicated, but in order to afford a weather protection this has not hitherto been feasible, as the general practice is to cover a roof ventilator in such a manner as to provide effective weather protection, and against the ingress f rain, the result being that the discharge from the unit is directed downwardly. The object of the present invention is to obviate the aforesaid disadvantages.
Upward discharges ventilators have hitherto embodied flaps which open upwards when the fan is operating and close to provide weather protection at other times.
According to the invention, an upward discharge ventilator comprises a cowling, a base inlet below which an exhaust fan is mounted and a top outlet to provide an upwardly directed discharge, a deflector mounted in said cowling and presenting a deflecting face or faces to said outlet, whereby a circuitous passage is formed within the cowling from inlet to outlet, said deflector forming a cover for said inlet and passages from said cowling for drainage purposes.
The upward discharge ventilator may be of rectangular or circular form in plan with rectangular and circular inlets and outlets respectively, the deflector with a circular construction being substantially of conical form.
Dampers may be fitted at the entry of the circuitous passage between the deflector and inlet, and the said dampers may be electrically or mechanically or gravity controlled.
Further, the circuitous passage may have fitted therein splitters shaped to the natural flow line, imparted to the air being exhausted.
In order that the invention may be clearly understood and readily carried into effect, reference is directed to the drawings, wherein:
FIGURE 1 is a perspective view of a forced draught extraction ventilation unit according to the invention.
FIGURE 2 illustrates diagrammatically in cross-section an extraction unit as illustrated in FIGURE 1.
FIGURE 3 is an end elevation of FIGURE 2, and
FIGURE 4 illustrates a detail.
FIGURE 5 is a similar view to FIGURE 2 illustrating a modified form of the invention.
FIGURE 6 is a side elevation of FIGURE 5 and FIGURE 7 is a perspective view of the cowl shown in FIGURE 5.
FIGURE 8 is a diagrammatic sectional elevation of a forced draught ventilator according to the present invention.
FIGURE 9 is a part sectional plan of FIGURE 1.
Referring firstly to FIGURES 1 to 4, a forced draught upward extraction unit for ventilation purposes is shown comprising a cowling 5 of rectangular form in plan, and consisting of two end plates 6 and 7 and side walls 8 and 9, the two latter walls being of semi-circular crosssection and fixed to the side walls in accordance with accepted practice.
The cowl 5 has a rectangular shaped air outlet 10 at the top, extending the full width of the cowl and a similar shaped air inlet passage 11 at the base. The inlet passage 11 has a flanged base 12, by means of which it is secured in place on a roof. The cowl 5 houses a deflector or shroud 13, which extends lengthwise between the walls 6 and 7 of the cowl and presents a convex surface 14 to the inlet 11 and concave surfaces 15, 15 to the outlet 10. The convex surface 14 marries into the concave surfaces 15, 15 at beaded edges 14a.
Shutters or dampers 16, 17 which also extend across the cowl between the walls 6 and 7 are hinged to the base of the deflector 13 as at Ma and 17a and are motor or gravity operated so as to prevent all air flow except when an exhaust fan such as 18 is in operation, suitable automatically controlled switch gear may be provided.
In certain circumstances, it may be desirable to install within the cowl 5, and extending between the two end walls 6 and 7 thereof splitters 159 and 20 which conform in shape to the expected flow path the air exhausted will take during operation of the exhaust fan 18. The splitters 19 and 20 serve to straighten the air flow and maintain performance.
In order to drain away rain water which may enter the outlet 10' and accumulate on the concave surfaces 15, drain outlets 21, 22 are provided in the walls 6 and 7 for escape purposes. In addition a longitudinal gap 23 (see FIGURE 4) is provided between the side walls 9 and the outlet passage 11 so that water accumulating at the base of the cowl will flow away to the roof of the building. It is also desirable to hinge the cowl along one side as at 24, so that access can be had to the exhaust fan 18 if necessary.
FIGURES 5, 6 and 7 show a modified form of ventilator similar in many respects to the cowl illustrated in FIGURES l to 4, the same reference numerals have been used for corresponding parts of both forms of ventilator. The major dilferences of the modified form of cowl consist in the provision of a larger air outlet 10 and that the deflector 13 is of reduced height and the convex surface 14 has a greater radius and extends as a continuous surface from the lines of joindure 14a with the deflector 13. In place of motor operated shutters or dampers 16 and 17, gravity type dampers may be embodied which open automatically upon the uprush of air from the ventilator fan, the motor 18 of which is now housed within the inlet passage 11.
The modified form of construction according to FIG- URES 5 to 7 results in that practically the whole of the top of the ventilator is open and the total height is considerably reduced whereby resistance is decreased. The cowl is completely waterproof when the fan is running or not. The gravity operated dampers 16, 17 when in the closed position prevent ingress or egress of air at times when such is not wanted.
Referring now to FIGURES 8 and 9 of the drawings, forced draught upward extraction unit is illustrated of circular form in plan and comprising a cowl 25 of hollow ring form providing a convex outer surface 26 and a concave inner surface 27. The cowling is removable mounted on a base 28 adapted to fixing to the roof of a building, the base housing the usual motor driven exhaust fan 13 as previously described. Within the cowl 25, is mounted a deflector or shroud 30 of circular form in plan presenting a convex base 31 to the base inlet 32 of the extraction unit and an apex 33 to the discharge outlet 34 thereof, the apex being the peak of a substantially conically shaped member, the walls of which curve sinuously in section to the perimeter of the defilector where it is united with the convex base 31. The deflector is connected to the cowl by radial stays 35.
Mounted on the base 28 are dampers 36 pivoted to a support 37 and are weighted so as to close by gravity when the uprush of air from the fan 18 ceases.
It will be appreciated that the circular form of cowl embodies the major features of the rectangular form of cowl and those features which have not been specifically described for example the splitters 20 may be installed in the cowl between the deflector and the inner wall thereof and conform in shape to the flow of the air exhausted.
The forced draught ventilation units according to the invention are preferably produced from light aluminium alloy or other suitable material; the cowling imparts an upward direction to exhaust air, and is permanently weatherproof regardless of operation of the fan or other moving parts. The unit is intended to lie on the plane of a roof and requires no adjustment to suit different roof angles. When the fan is out of use, the cowl can be allowed to act as a natural exhaust ventilator. The cowl is hinged to open externally to give free access to the installation, removal, or maintenance of fan and motor. The construction due to the shape has a low resistance to air flow.
The motor operated shutters 16, 17 of the construction shown in FIGURES 1 to 4 prevent all air-flow except when the fan 18 is operating, in contrast to the gravity closing dampers which float open in the airstream, as embodied in the construction according to FIGURES to 6.
What I claim and desire to secure by Letters Patent is:
1. An upward discharge ventilator unit comprising a cowling rectangular in plan with a pair of end plates and a pair of semi-circular side walls presenting a rec tangular air outlet at the top extending the full width of the cowling between the side walls, a base with base walls on which said cowling is mounted and having an air inlet passage communicating with the interior of the cowling, an exhaust fan mounted in the air inlet passage and an air outlet passage in the top of the cowling to provide an upwardly directed discharge, a deflector mounted lengthwise in the cowling between the cowling end plates and having upwardly inclined concave surfaces meeting in a ridge at the top opening and a bottom convex wall to the outer edges of which the lower edges of said surfaces are secured, said outer edges extending into the side walls beyond the edges of the inlet and outlet openings, there being a gap between the base walls and the lower edges of the side walls, and draining passages in said end walls positioned at the lower ends of said upwardly inclined concave surfaces, whereby a circuitous passage is formed within the cowling from inlet to outlet and said deflector forms an inlet cover and dampers disposed between the end plates, hinged to the underside of the deflector and extending from the upwardly curved surfaces of the bottom convex wall of the deflector to the upper edges of the base walls normally substantially completely blocking communication between said air inlet passage and the interior of its cowling.
2. An upward discharge ventilator according to claim 1 wherein the cowling has a concave inner wall surface and is of rectangular form in plan with rectangularly shaped inlet and outlet.
3. An upward discharge ventilator according to claim 1 wherein the cowling is of circular form in plan with a circular shaped inlet and outlet.
4. An upward discharge ventilator according to claim 1 wherein said dampers are fitted at the entry of the circuitous passage between the deflector and inlet, the said dampers being provided with control means.
5. An upward discharge ventilator according to claim 1 wherein splitters, shaped to the natural flow line, imparted to the air being exhausted are fitted Within the circuitous passage.
6. Unit as claimed in claim 1 in which the cowling is of hollow ring form providing a convex outer surface and a concave inner surface, an upper circular discharge outlet and a lower circular base inlet, the deflector being circular presenting a convex base to the inlet and an apex to the discharge outlet, the apex being the peak of a substantially conically shaped member whose walls curve sinuously in section to the perimeter of the deflector where it is united with the convex base and forms with the inner cowl wall a curvilinear passage.
References Cited in the file of this patent UNITED STATES PATENTS 2,232,027 Gunter Feb. 18, 1941 2,322,302 Martinson June 22, 1943 2,404,961 Hoch July 30, 1946 2,406,168 Shumaker Aug. 20, 1946 2,805,615 Rudy Sept. 10, 1957 2,895,399 OHea July 21, 1959 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, 3,053,165 September 11 1962 Kenneth Rampley It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.
In the heading .to the printed specification line 7, for "Oct., 28, 1959" read Oct 28 1958 column 1,, line 42, for "discharges" read discharge --a.
Signed and sealed this 8th ,day of January 1963.
(SEAL) Attest:
ERNEST w. swIDEE DAVID LADD Attesting Officer Commissioner of Patents
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2412035A1 (en) * 1977-12-14 1979-07-13 Robertson Uk Ltd H H STATIC VACUUM CLEANERS FOR BUILDINGS
DE102008053510A1 (en) * 2008-10-28 2010-04-29 Pötter Klima GmbH Guide surface ventilator for use at e.g. flat roof for ventilation of interior of building, has side walls, guide plates, guide surfaces or regulating flaps possessing wing-like curved contour

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2232027A (en) * 1939-03-10 1941-02-18 William H Klauer Ventilator
US2322302A (en) * 1940-12-23 1943-06-22 American Machine & Metals Ventilator
US2404961A (en) * 1942-12-30 1946-07-30 Klauer Mfg Company Ventilator
US2406168A (en) * 1943-05-05 1946-08-20 Robertson Co H H Ventilating apparatus
US2805615A (en) * 1954-10-04 1957-09-10 Loren Cook Company Ventilators
US2895399A (en) * 1955-07-06 1959-07-21 Colt Ventilation Ltd Ventilators

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2232027A (en) * 1939-03-10 1941-02-18 William H Klauer Ventilator
US2322302A (en) * 1940-12-23 1943-06-22 American Machine & Metals Ventilator
US2404961A (en) * 1942-12-30 1946-07-30 Klauer Mfg Company Ventilator
US2406168A (en) * 1943-05-05 1946-08-20 Robertson Co H H Ventilating apparatus
US2805615A (en) * 1954-10-04 1957-09-10 Loren Cook Company Ventilators
US2895399A (en) * 1955-07-06 1959-07-21 Colt Ventilation Ltd Ventilators

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2412035A1 (en) * 1977-12-14 1979-07-13 Robertson Uk Ltd H H STATIC VACUUM CLEANERS FOR BUILDINGS
DE102008053510A1 (en) * 2008-10-28 2010-04-29 Pötter Klima GmbH Guide surface ventilator for use at e.g. flat roof for ventilation of interior of building, has side walls, guide plates, guide surfaces or regulating flaps possessing wing-like curved contour

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