US2582902A - Power-operated ventilator - Google Patents

Power-operated ventilator Download PDF

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Publication number
US2582902A
US2582902A US195094A US19509450A US2582902A US 2582902 A US2582902 A US 2582902A US 195094 A US195094 A US 195094A US 19509450 A US19509450 A US 19509450A US 2582902 A US2582902 A US 2582902A
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disposed
edge
housing
fan
collar
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US195094A
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Fred H Gohl
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CHICAGO BLOWER CORP
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CHICAGO BLOWER CORP
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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

Definitions

  • This, invention relates, to a power operated ventilator, and more, particularly to a. centrifugal tan having an axially disposed; inlet andan annular discharge outlet which particularly adapts the ventilator for use in a roof installation or the like.
  • Another object is to provide a; ventilator oi the character described which incorporates cutofi type air guiding vanes. which shear off. the air at theperipheral edge. of the fan-wheel, which shearing, action permits thefan to-operate against static pressures unknown in. ordinary centrifugal roof ventilator design.
  • 'Yet another object is, to provide a ventilator of the character described. in. which. the. air isv sheared off the edge of. the, wheel at. approximately every 60 of angular rotation, andin which the air is discharged in. a. complete. 360'? are, through an annular discharge passage which 11 is so disposed and designed. as to keep. discharge losses at a minimum.
  • Figure 1 is a view inside elevation and partly in vertical cross-section of' one form of" ventilator embodying this invention.
  • Figure 2 is a view in horizontal cross-section with parts broken away; the view being taken along the line 22'of Figure-l I
  • aventilator mili c'ated generally by the numeral It
  • the ventilator is provided with 'abase member-14' adapted to fit over the curb i2 and having a central opening it therein which is in communication with the opening ill in the curb I2.
  • the base M may have an inlet cellar 29; mounted thereon dual alignment therewith in the form of a shallow truncated cone having its edge of lesser diameter uppermost.
  • a collar member 2 2' of larger diameter than inlet collar 'Z-il is provided which also may have the form-oi a truncated cone and have its edge of greater diameter secured to the base member Hi,
  • the collar member 2 2 being disposed in axial alignment with and encompassing relation tothe inlet collar 28.
  • a plurality of upstanding angularly' disposed air baifle plates '24 may be provided which may besecured at the base thereof'to the inlet collar 22', so that theyextend upwardly therefrom into fixed and supporting relation with the base 26 of the substantially cylindrical housing 28'.
  • these anbaffle plates 2! are symmetrically disposedabout the inlet collar 22, and have an angularrelation such that each forms substantially the same angle with a line drawn tangent to the circular opening in, the inlet collar- '22- at the point at which the inner ed'geof each such baffle plate substantially coincides with that circular opening.
  • a fan wheel; 32' is disposed in axial alignment with the center-ofthe opening loin the base member i i and the; circular opening in the upper end of the-inlet collar 20.
  • the fan wheel 32 may lee-composed of the inclined blades 34, as best'showrr in Figure- 2, the circular plate 36 towhich the upper edge of the blades '34 are adaptedi as by welding, the substantially conical plate 38" to which the lower edgesof the blades 3d are similarly attached, and the-hub 473.
  • the conical plate 38 may have a lip3'5-formed-onits edge of lesser diameter which isdisposed in overlapping relation with a similar lip formed on the upper "edge of the inlet collar "20.
  • the edge of greater diameter of the conical plate 36 is in relatively close association with the edge of lesser diameter of the collar member 22-.
  • the ultimate result is that thefarr wheel 32" is mounted so "as have anaxiallv alignedjinlet associated with the circular opening hr-the lhl'et' collar 20',
  • the fan wheel 32 is secured to the shaft 42 by the hub 48, the shaft 42 being Journalled in suitable bearings (not shown), carried by the bearing and motor housing 48, which is in turn supported by vibration dampeners, such as 48 and 58.
  • the upper end of the shaft 42 has the pulley wheel 44 secured thereto.
  • the electric motor 52 is mounted in the motor and bearing housing 46, and has the pulley wheel 54 secured to the shaft thereof and disposed in substantially the same plane as the pulley wheel 44, so that the latter may be driven thereby through the use of a v-belt or the like.
  • Th housing 28 may be suitably enclosed by the removable cover '6.
  • a skirt or collar member 58 in the form oi. a truncated cone may be provided at the lower edge of the housing 28, the collar member 58 being disposed so as to extend downwardly and outwardly in substantial parallel relation to the collar member 22.
  • This disposition of the collar members 58 and 22 provides an annular discharge passage 69, which has the angularly disposed baffle plates 24 disposed at the inner periphery thereof.
  • the Ian wheel 32 When the ventilator is in operation, the Ian wheel 32 is rotated in a counter-clockwise direction, as indicated by the arrow 59 in Figure 2. Since the inclined blades 34 are disposed in angularly opposed relation to the baflle plates 24, a definite shearing action occurs as the air is thrown outwardly from the periphery of the fan wheel 32 when it rotates rapidly. As previously mentioned, this shearing action of the bafiie plates 24 permits the fan wheel 32 to operate against static pressures previously unknown in roof ventilator design. The discharge losses are kept to a minimum by permitting the air which is sheared oil the edge of the fan wheel 32 to be discharged through the discharge passage 68 in a complete 360 arc.
  • a very desirable and novel ventilation of the motor compartment is provided. This ventilation is produced by having the upper edge of the fan wheel disposed immediately below the horizontal plane of the base 25' of the housing 28, and in axial alignment with the opening 38 therein. The centrifugal action of the fan wheel 32, in addition to forcing the air out through the discharge passage 60.
  • a power operated ventilator comprising a fan housing having an axially disposed inlet and an annular discharge outlet, a multi-bladed power driven fan rotatably disposed in said housing. with its axis of rotation substantially coincident with the axis of said inlet, the annular discharge outlet being disposed in substantial alignment with the outer edge of the blades of said fan.
  • a collar member forming a part of said housing substantially in the form of a truncated cone having the edge of lesser diameter disposed in close association with the lower edge of said blades, a plurality of upstanding air baiiie plates disposed on said collar member in close association with said blades but in angularly opposed relation thereto, a substantially cylindrical portion of said housing having the upper ends of said air baffle plates secured thereto being disposed immediately above and in axial alignment with said fan, the base of said cylindrical portion having a centrally disposed opening therein in substantial alignment with said fan, a second collar member in the form of a truncated cone having its edge of lesser diameter secured to the lower edge of said cylindrical portion of said housing, said collar members being disposed in substantially parallel relation so as to form an annular passage in communication'with said annular discharge outlet.
  • a power operated ventilator comprising a substantially cylindrical housing, a prime mover disposed in said housing, a shaft axially aligned with and depending from said-housing adapted to be rotated by said prime mover, a multibladed fan mounted on the depending portion of said shaft, the base of said cylindrical housing having an opening therein in substantial alignment with said fan, a plurality of angularly disposed air bafiie plates depending from the base of said cylindrical housing having their inner edges in close association with the blades of said fan, a collar member substantially in the shape of a truncated cone having its edge of lesser diameter disposed in close association with the lower edge of said blades, and having the lower extremities of saidair bafllle plates secured thereto, a base member to which the opposite edge of said collar member is.
  • an inlet cone disposed within said collar member having its lower edge secured -to said base member and its'upper edge extending into close association with said fan, and a second collar member substantially in the shape of a truncated cone having its edge of lesser diameter disposed in secured relation to said cylindrical housing and protruding outwardly in substantially parallel relationto said first named collar member, said collar' members" and said base of said housing therefor forming a substantially annular dischargepassage communicating with the peripheral edge of said multi-bladed fan.
  • a power operated ventilator comprising an annular base member having a central opening therein, a collar member substantially in the form of a truncated cone having the edge of greater diameter secured to said annular base member, a plurality of upstanding, annularly disposed-air baflie plates disposed on said collar member and extending upwardly into association with the base of a substantially cylindrical housing, said base of said housing having a centrally disposed opening therein.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)

Description

J 1952 F. H. GOHL PQWER-OPERATED VENTILATOR Filed Nov. 10, 1950 f INVENTOR. I 2766M 60 25, j fl/g,
Patented Jan. 15, 1952 TENT OFFICE.
rownn orcasrentenrmairon H Fred. H. Gohl, omee, 111.,tssighor to Chicago Blower Corporation; Chicago, 111., ncorporation er Illinois:
ss iic manovembemo, 1950,.serni'Ne19ao94 (crass-4a).-
K'Glainia.
This, invention relates, to a power operated ventilator, and more, particularly to a. centrifugal tan having an axially disposed; inlet andan annular discharge outlet which particularly adapts the ventilator for use in a roof installation or the like.
It is an. object of. this, invention, to provide ventilator of the. character described which has a relatively low noise level, and yet which provides an efiicient flow of air under all. conditions of use, which flow is greatly superior to that produced by a centrifugal fan of ordinary design.
Another object is to provide a; ventilator oi the character described which incorporates cutofi type air guiding vanes. which shear off. the air at theperipheral edge. of the fan-wheel, which shearing, action permits thefan to-operate against static pressures unknown in. ordinary centrifugal roof ventilator design.
'Yet another object is, to provide a ventilator of the character described. in. which. the. air isv sheared off the edge of. the, wheel at. approximately every 60 of angular rotation, andin which the air is discharged in. a. complete. 360'? are, through an annular discharge passage which 11 is so disposed and designed. as to keep. discharge losses at a minimum.
sun another object is, to provide. a ventilator' Further objects and advantagesof this inven== k tion will become evident as the description pro-f ceeds and from an examination of the acco'm panying drawing which illustrates one embodiment of the invention, and in which similarnw' meralsrefer to similar parts throughout theseve eral views. a
In the drawings: Figure 1 isa view inside elevation and partly in vertical cross-section of' one form of" ventilator embodying this invention; and
Figure 2 is a view in horizontal cross-section with parts broken away; the view being taken along the line 22'of Figure-l I Referring now to Figure- 1 aventilator, mili c'ated generally by the numeral It, is disclosed therein mounted associationwith a curb I2, which maybe formedas an integral part of a roof, for example. The ventilator is provided with 'abase member-14' adapted to fit over the curb i2 and having a central opening it therein which is in communication with the opening ill in the curb I2. The base M may have an inlet cellar 29; mounted thereon dual alignment therewith in the form of a shallow truncated cone having its edge of lesser diameter uppermost.
A collar member 2 2' of larger diameter than inlet collar 'Z-il is provided which also may have the form-oi a truncated cone and have its edge of greater diameter secured to the base member Hi,
the collar member 2 2 being disposed in axial alignment with and encompassing relation tothe inlet collar 28. A plurality of upstanding angularly' disposed air baifle plates '24 may be provided which may besecured at the base thereof'to the inlet collar 22', so that theyextend upwardly therefrom into fixed and supporting relation with the base 26 of the substantially cylindrical housing 28'. As best shown Figure 2, these anbaffle plates 2! are symmetrically disposedabout the inlet collar 22, and have an angularrelation such that each forms substantially the same angle with a line drawn tangent to the circular opening in, the inlet collar- '22- at the point at which the inner ed'geof each such baffle plate substantially coincides with that circular opening.
Immediately belowthe central opening 36 in the-base- 26 or the cylindrical housing 28', a fan wheel; 32' is disposed in axial alignment with the center-ofthe opening loin the base member i i and the; circular opening in the upper end of the-inlet collar 20.
The fan wheel 32 may lee-composed of the inclined blades 34, as best'showrr in Figure- 2, the circular plate 36 towhich the upper edge of the blades '34 are adaptedi as by welding, the substantially conical plate 38" to which the lower edgesof the blades 3d are similarly attached, and the-hub 473. As shown in Figure 1, the conical plate 38 may have a lip3'5-formed-onits edge of lesser diameter which isdisposed in overlapping relation with a similar lip formed on the upper "edge of the inlet collar "20. The edge of greater diameter of the conical plate 36 is in relatively close association with the edge of lesser diameter of the collar member 22-. The ultimate result is that thefarr wheel 32" is mounted so "as have anaxiallv alignedjinlet associated with the circular opening hr-the lhl'et' collar 20',
and so that its peripheral edge is disposed in relatively close association with the inner edges of the angularly disposed air bafile plates 24.
The fan wheel 32 is secured to the shaft 42 by the hub 48, the shaft 42 being Journalled in suitable bearings (not shown), carried by the bearing and motor housing 48, which is in turn supported by vibration dampeners, such as 48 and 58. The upper end of the shaft 42 has the pulley wheel 44 secured thereto. The electric motor 52 is mounted in the motor and bearing housing 46, and has the pulley wheel 54 secured to the shaft thereof and disposed in substantially the same plane as the pulley wheel 44, so that the latter may be driven thereby through the use of a v-belt or the like. Th housing 28 may be suitably enclosed by the removable cover '6.
A skirt or collar member 58 in the form oi. a truncated cone may be provided at the lower edge of the housing 28, the collar member 58 being disposed so as to extend downwardly and outwardly in substantial parallel relation to the collar member 22. This disposition of the collar members 58 and 22 provides an annular discharge passage 69, which has the angularly disposed baffle plates 24 disposed at the inner periphery thereof.
When the ventilator is in operation, the Ian wheel 32 is rotated in a counter-clockwise direction, as indicated by the arrow 59 in Figure 2. Since the inclined blades 34 are disposed in angularly opposed relation to the baflle plates 24, a definite shearing action occurs as the air is thrown outwardly from the periphery of the fan wheel 32 when it rotates rapidly. As previously mentioned, this shearing action of the bafiie plates 24 permits the fan wheel 32 to operate against static pressures previously unknown in roof ventilator design. The discharge losses are kept to a minimum by permitting the air which is sheared oil the edge of the fan wheel 32 to be discharged through the discharge passage 68 in a complete 360 arc.
In addition to the improved efliciency provided by the power operated ventilator which is the' subject matter of this invention, with respect to the movement of the air out through the discharge passage 60, a very desirable and novel ventilation of the motor compartment is provided. This ventilation is produced by having the upper edge of the fan wheel disposed immediately below the horizontal plane of the base 25' of the housing 28, and in axial alignment with the opening 38 therein. The centrifugal action of the fan wheel 32, in addition to forcing the air out through the discharge passage 60. will therefore cause a reduction of air pressure within thehousing 28, and will insure a positive air movement through the housing 28, which air will enter between the cover 56 and the upper edge of the housing 28, and will pass through the motor compartment and then down into the discharge passage through the opening 30 in the base 26 in the housing 28. Such a circulation of air through the motor compartment is, of course, very desirable.
, The drawing and the above discussion are not intended to represent theonly possible form of this invention, in regard to details of construction. Changes in form and in the proportion of parts, as well as the substitution of equivalents, are contemplated, as circumstances may suggest or render expedient, without departing from the spirit or scope of this invention as further de fin d iefl isx lqwms laim What isclaimed is:
1. A power operated ventilator comprising a fan housing having an axially disposed inlet and an annular discharge outlet, a multi-bladed power driven fan rotatably disposed in said housing. with its axis of rotation substantially coincident with the axis of said inlet, the annular discharge outlet being disposed in substantial alignment with the outer edge of the blades of said fan. a collar member forming a part of said housing substantially in the form of a truncated cone having the edge of lesser diameter disposed in close association with the lower edge of said blades, a plurality of upstanding air baiiie plates disposed on said collar member in close association with said blades but in angularly opposed relation thereto, a substantially cylindrical portion of said housing having the upper ends of said air baffle plates secured thereto being disposed immediately above and in axial alignment with said fan, the base of said cylindrical portion having a centrally disposed opening therein in substantial alignment with said fan, a second collar member in the form of a truncated cone having its edge of lesser diameter secured to the lower edge of said cylindrical portion of said housing, said collar members being disposed in substantially parallel relation so as to form an annular passage in communication'with said annular discharge outlet.
2. A power operated ventilator comprising a substantially cylindrical housing, a prime mover disposed in said housing, a shaft axially aligned with and depending from said-housing adapted to be rotated by said prime mover, a multibladed fan mounted on the depending portion of said shaft, the base of said cylindrical housing having an opening therein in substantial alignment with said fan, a plurality of angularly disposed air bafiie plates depending from the base of said cylindrical housing having their inner edges in close association with the blades of said fan, a collar member substantially in the shape of a truncated cone having its edge of lesser diameter disposed in close association with the lower edge of said blades, and having the lower extremities of saidair bafllle plates secured thereto, a base member to which the opposite edge of said collar member is. secured, an inlet cone disposed within said collar member having its lower edge secured -to said base member and its'upper edge extending into close association with said fan, and a second collar member substantially in the shape of a truncated cone having its edge of lesser diameter disposed in secured relation to said cylindrical housing and protruding outwardly in substantially parallel relationto said first named collar member, said collar' members" and said base of said housing therefor forming a substantially annular dischargepassage communicating with the peripheral edge of said multi-bladed fan.
3. A power operated ventilator comprising an annular base member having a central opening therein, a collar member substantially in the form of a truncated cone having the edge of greater diameter secured to said annular base member, a plurality of upstanding, annularly disposed-air baflie plates disposed on said collar member and extending upwardly into association with the base of a substantially cylindrical housing, said base of said housing having a centrally disposed opening therein. a multi-bladed power driven ianrotatably disposed immediately below said opening in said base of said housing, the outer edges of the blades of said fan being disposed in close association with the inner edges of said air baffle plates and the edge of lesser diameter of said collar member, an inlet cone secured to said base member and axially aligned with the opening in said base member and said fan member, the edge of lesser diameter of said inlet cone being disposed in close association with the base of said fan, a second collar member substantially in the form of a truncated cone having the edge of lesser diameter secured to the lower edge of said housing and protruding outwardly in substantially parallel relation to said first named collar member, said collar members and said base of said housing therefor forming a substantially annular discharge passage communicating with said fan.
FRED H. GOHL.
REFERENCES CITED The followingreferences are of record in the file of this patent:
UNITED STATES PATENTS
US195094A 1950-11-10 1950-11-10 Power-operated ventilator Expired - Lifetime US2582902A (en)

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Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2649040A (en) * 1950-11-15 1953-08-18 Knutson Harold Power exhauster
US2666378A (en) * 1952-03-22 1954-01-19 Cecil L Ammerman Ventilator
US2774293A (en) * 1953-03-27 1956-12-18 Louis J Jenn Roof exhauster
US2784661A (en) * 1953-01-26 1957-03-12 Louis J Jenn Ventilating device
US2831416A (en) * 1955-08-17 1958-04-22 Doherty Lewis Stirling Roof ventilator of the forced air draft type
US2982198A (en) * 1958-11-13 1961-05-02 Chelsea Products Inc Ventilator
US3011423A (en) * 1958-11-03 1961-12-05 G C Breidert Co Ventilator construction
US3011693A (en) * 1956-12-05 1961-12-05 Clarage Fan Company Apparatus relating to centrifugal wheel inlet boundary control
US3016003A (en) * 1959-11-23 1962-01-09 Jenn Air Products Company Inc Offset belted roof ventilator
US3063358A (en) * 1959-05-15 1962-11-13 G C Breidert Co Roof-type ventilation device
US3303996A (en) * 1965-04-28 1967-02-14 Electrolux Corp Fan having annular frustro-conical diffuser space
US3412670A (en) * 1966-12-20 1968-11-26 Jenn Air Corp Roof ventilator
FR2377577A1 (en) * 1977-01-14 1978-08-11 Zaniewski Michel DEVICE FOR MAINTAINING AND CONTROLLING A DEPRESSION AT THE END OF A VENTILATION OR SMOKE DUCT
US4890547A (en) * 1989-01-27 1990-01-02 Carnes Company, Inc. Ventilator scroll arrangement

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1350927A (en) * 1918-11-26 1920-08-24 Gen Electric Centrifugal compressor
US2157609A (en) * 1937-05-17 1939-05-09 Perey H Waller Ventilator
US2362514A (en) * 1941-06-03 1944-11-14 Gen Electric Centrifugal compressor
US2526290A (en) * 1949-07-21 1950-10-17 Isel I Solzman Air exhauster

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1350927A (en) * 1918-11-26 1920-08-24 Gen Electric Centrifugal compressor
US2157609A (en) * 1937-05-17 1939-05-09 Perey H Waller Ventilator
US2362514A (en) * 1941-06-03 1944-11-14 Gen Electric Centrifugal compressor
US2526290A (en) * 1949-07-21 1950-10-17 Isel I Solzman Air exhauster

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2649040A (en) * 1950-11-15 1953-08-18 Knutson Harold Power exhauster
US2666378A (en) * 1952-03-22 1954-01-19 Cecil L Ammerman Ventilator
US2784661A (en) * 1953-01-26 1957-03-12 Louis J Jenn Ventilating device
US2774293A (en) * 1953-03-27 1956-12-18 Louis J Jenn Roof exhauster
US2831416A (en) * 1955-08-17 1958-04-22 Doherty Lewis Stirling Roof ventilator of the forced air draft type
US3011693A (en) * 1956-12-05 1961-12-05 Clarage Fan Company Apparatus relating to centrifugal wheel inlet boundary control
US3011423A (en) * 1958-11-03 1961-12-05 G C Breidert Co Ventilator construction
US2982198A (en) * 1958-11-13 1961-05-02 Chelsea Products Inc Ventilator
US3063358A (en) * 1959-05-15 1962-11-13 G C Breidert Co Roof-type ventilation device
US3016003A (en) * 1959-11-23 1962-01-09 Jenn Air Products Company Inc Offset belted roof ventilator
US3303996A (en) * 1965-04-28 1967-02-14 Electrolux Corp Fan having annular frustro-conical diffuser space
US3412670A (en) * 1966-12-20 1968-11-26 Jenn Air Corp Roof ventilator
FR2377577A1 (en) * 1977-01-14 1978-08-11 Zaniewski Michel DEVICE FOR MAINTAINING AND CONTROLLING A DEPRESSION AT THE END OF A VENTILATION OR SMOKE DUCT
US4200035A (en) * 1977-01-14 1980-04-29 Zaniewski Michel Henry Modular ventilating assembly
US4890547A (en) * 1989-01-27 1990-01-02 Carnes Company, Inc. Ventilator scroll arrangement

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