US4173995A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recirculation barrier for a heat transfer system
Assignee: Case LLC
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Filing: 1977-09-30
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Granted: 1979-11-13
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Expires: 1997-09-30
Abstract
Abstract A heat exchanger apparatus for a liquid-cooled internal combustion engine including a radiator axially spaced from the engine, an engine-driven, suction-type fan axially spaced intermediate the engine and the radiator for drawing cooling air axially through the radiator, fan shroud means shaped and positioned with respect to the radiator and blades of the fan whereby the air stream discharged by the fan is in a radial outward direction, and an air baffle positioned intermediate the fan and engine for mitigating air recirculation in the fan hub region; the fan shroud structure is formed to provide a generally cylindrical exit throat section (CF), a radial flat discharge section (RF), and a radial expander or diverging section (R), serving as a transition between the throat section and the discharge section, and wherein the impeller blades of the fan have a projected or effective axial width (AW); the various shroud structure sections are dimensioned with respect to such projected or effective axial width (AW) of the fan blades and the fan blades are positioned with respect to the shroud structure sections in the following manner: CF=AW/3, RF=AW/3, R=2AW/3, and the radial plane defining one axial limit of the projected or effective axial width (AW) of the fan blades substantially contains the radial discharge section (RF).
Inventors
- 👤 Harold D. Beck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:21
CPC Classifications
B; B60; B60K; B60K11/00; B60K11/02; F; F01; F01P; F01P5/00; F01P5/02; F01P5/06; F04; F04D; F04D29/00; F04D29/26; F04D29/32; F04D29/38; F04D29/384; Y; Y10; Y10S; Y10S415/00; Y10S415/914
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
458 words
A heat exchange apparatus comprising: a heat exchange means having air intake and air discharge faces; a rotatable axial flow, suction-type fan having a plurality of circumferentially spaced impeller blades extending radially from a hub and positioned on one side of said heat exchange means adjacent said air discharge face for drawing air through said heat exchange means axially in a direction from said air intake face to said air discharge face, said air flow through said heat exchange means having a major velocity component parallel with respect to the rotational axis of the fan, each of said blades having an effective axial width AW measured axially along the rotational axis of the fan between a first plane and a second plane, said planes being axially spaced and parallel with respect to each other and disposed substantially normal to the rotational axis of the fan, said first and second planes extending radially, respectively, through a point on the leading edge of each of the blades at the tip portion thereof and through a point on the trailing edge of each of the blades at the tip portion thereof; shroud means having one axial end operatively connected to said heat exchange and encircling said fan, said shroud means being shaped and positioned with respect to said heat exchange means and the blades of said fan whereby the major velocity component of the air stream discharge by the fan is in a direction perpendicular to the direction of the major velocity component of the air stream entering the air intake face and flowing through said heat exchange means, said shroud means including a generally cylindrical, axially extending throat section, one axial end of said throat section substantially defining said one axial end of said shroud means operatively connected to said heat exchange means, said one axial end of said throat section lying substantially in a plane disposed substantially perpendicular to the rotational axis of said fan, one of said first and second planes being axially spaced from and on either axial side of said plane containing said one axial end of said throat section of said shroud means a distance of 12 percent of AW; and means axially positioned on the side of said fan opposite said heat exchange means for obstructing flow of air axially through the fan at the hub region thereof in an axial direction opposite the direction of said major velocity component of air flow through said heat exchange means, said means lying substantially in a plane spaced and substantially parallel with respect to a radial plane substantially defining a second axial end of said shroud means opposite said one axial end of said throat section substantially defining said one axial end of said shroud means.
Claim 2
Dependent Claim
458 words
A heat exchange apparatus comprising: a heat exchange means having air intake and air discharge faces; a rotatable axial flow, suction-type fan having a plurality of circumferentially spaced impeller blades extending radially from a hub and positioned on one side of said heat exchange means adjacent said air discharge face for drawing air through said heat exchange means axially in a direction from said air intake face to said air discharge face, said air flow through said heat exchange means having a major velocity component parallel with respect to the rotational axis of the fan, each of said blades having an effective axial width AW measured axially along the rotational axis of the fan between a first plane and a second plane, said planes being axially spaced and parallel with respect to each other and disposed substantially normal to the rotational axis of the fan, said first and second planes extending radially, respectively, through a point on the leading edge of each of the blades at the tip portion thereof and through a point on the trailing edge of each of the blades at the tip portion thereof; shroud means having one axial end operatively connected to said heat exchange and encircling said fan, said shroud means being shaped and positioned with respect to said heat exchange means and the blades of said fan whereby the major velocity component of the air stream discharge by the fan is in a direction perpendicular to the direction of the major velocity component of the air stream entering the air intake face and flowing through said heat exchange means, said shroud means including a generally cylindrical, axially extending throat section, one axial end of said throat section substantially defining said one axial end of said shroud means operatively connected to said heat exchange means, said one axial end of said throat section lying substantially in a plane disposed substantially perpendicular to the rotational axis of said fan, one of said first and second planes being axially spaced from and on either axial side of said plane containing said one axial end of said throat section of said shroud means a distance of 12 percent of AW; and means axially positioned on the side of said fan opposite said heat exchange means for obstructing flow of air axially through the fan at the hub region thereof in an axial direction opposite the direction of said major velocity component of air flow through said heat exchange means, said means lying substantially in a plane spaced and substantially parallel with respect to a radial plane substantially defining a second axial end of said shroud means opposite said one axial end of said throat section substantially defining said one axial end of said shroud means.
Claim 3
Dependent Claim
101 words
A heat exchange apparatus as set forth in claim 1, wherein: said means positioned on the side of said fan opposite said heat exchange means for obstructing flow of air axially through the fan at the hub region thereof in an axial direction opposite the direction of said major velocity component of air flow through said heat exchange means includes a generally circular, substantially flat disk which is spaced from said radial plane substantially defining said second axial end of said shroud means a distance along the rotational axis of said fan about 15 percent of the diameter of the fan.
Claim 4
Dependent Claim
50 words
A heat exchange apparatus as set forth in claim 2, wherein: said second axial end of said shroud means includes a generally annular portion, and rthe radially outermost periphery of said annular portion defined by a circle having a diameter substantially equal to the outermost diameter of said circular disk.
Claim 5
Dependent Claim
49 words
A heat exchange apparatus as set forth in claim 1, wherein: said radial plane containing said one axial end of said throat section defining said one axial end of said shroud means is substantially coincident with said first plane partially defining the axial width AW of the fan blades.
Claim 6
Dependent Claim
60 words
A heat exchange apparatus as set forth in claim 4 wherein: said radial plane substantially defining said second axial end of said shroud means opposite said one axial end of said throat section substantially defining said one axial end of said shroud means is substantially coincident with said second plane partially defining the axial width AW of said fan blades.
Claim 7
Dependent Claim
407 words
A heat exchange apparatus comprising: a generally upright radiator having air intake and air discharge faces; a rotatable axial flow, suction-type fan having a plurality of circumferentially spaced impeller blades extending radially from a hub and positioned on one side of said radiator adjacent said air discharge face for drawing air through said radiator axially in a direction from said air intake face to said air discharge face, said air flow through said radiator having a major velocity component parallel with respect to the rotational axis of the fan, each of said blades having an effective axial width AW measured axially along the rotational axis of the fan between a first plane and a second plane, said planes being axially spaced and parallel with respect to each other and disposed substantially normal to the rotational axis of the fan, said first and second planes extending radially, respectively, through a point on the leading edge of each of the blades at the tip portion thereof and through a point on the trailing edge of each of the blades at the tip portion thereof; shroud means having one axial end operatively connected to said radiator and encircling said fan, said shroud means being shaped and positioned with respect to said radiator and the blades of said fan whereby the major velocity component of the air stream discharged by the fan is in a direction perpendicular to the direction of the major velocity component of the air stream entering the air intake face and flowing through said radiator, the axial end of said shroud means remote from said axial end operatively connected to said radiator being defined by an annular, radially outwardly extending flat portion lying substantially in a plane disposed perpendicular to the rotational axis of said fan, one of said first and second planes being axially spaced from and on either axial side of the plane containing said annular radially outwardly extending flat portion of said shroud means a distance of 12 percent or less of AW; and means axially positioned on the side of said fan opposite said radiator for obstructing flow of air axially through the fan at the hub region thereof in an axial direction opposite the direction of said major velocity component of air flow through said radiator, said means lying substantially in a plane spaced and substantially parallel with respect to said plane in which said flat portion of said shroud means lies.
Claim 8
Dependent Claim
407 words
A heat exchange apparatus comprising: a generally upright radiator having air intake and air discharge faces; a rotatable axial flow, suction-type fan having a plurality of circumferentially spaced impeller blades extending radially from a hub and positioned on one side of said radiator adjacent said air discharge face for drawing air through said radiator axially in a direction from said air intake face to said air discharge face, said air flow through said radiator having a major velocity component parallel with respect to the rotational axis of the fan, each of said blades having an effective axial width AW measured axially along the rotational axis of the fan between a first plane and a second plane, said planes being axially spaced and parallel with respect to each other and disposed substantially normal to the rotational axis of the fan, said first and second planes extending radially, respectively, through a point on the leading edge of each of the blades at the tip portion thereof and through a point on the trailing edge of each of the blades at the tip portion thereof; shroud means having one axial end operatively connected to said radiator and encircling said fan, said shroud means being shaped and positioned with respect to said radiator and the blades of said fan whereby the major velocity component of the air stream discharged by the fan is in a direction perpendicular to the direction of the major velocity component of the air stream entering the air intake face and flowing through said radiator, the axial end of said shroud means remote from said axial end operatively connected to said radiator being defined by an annular, radially outwardly extending flat portion lying substantially in a plane disposed perpendicular to the rotational axis of said fan, one of said first and second planes being axially spaced from and on either axial side of the plane containing said annular radially outwardly extending flat portion of said shroud means a distance of 12 percent or less of AW; and means axially positioned on the side of said fan opposite said radiator for obstructing flow of air axially through the fan at the hub region thereof in an axial direction opposite the direction of said major velocity component of air flow through said radiator, said means lying substantially in a plane spaced and substantially parallel with respect to said plane in which said flat portion of said shroud means lies.
Claim 9
Dependent Claim
99 words
A heat exchange apparatus as set forth in claim 6, wherein: said means positioned on the side of said fan opposite said radiator for obstructing flow of air axially through the fan at the hub region thereof in an axial direction opposite the direction of said major velocity component of air flow through said radiator includes a generally circular, substantially flat disk which is spaced from said plane in which said radially outwardly extending flat portion of said shroud means lies a distance along the rotational axis of said fan about 15 percent of the diameter of the fan.
Claim 10
Dependent Claim
38 words
A heat exchange apparatus as set forth in claim 7, wherein: the radially outermost periphery of said radial flat portion being defined by a circle having a diameter substantially the same as the diameter of said flat disk.
Claim 11
Dependent Claim
36 words
A heat exchange apparatus as set forth in claim 6, wherein: one of said first and second planes is substantially coincident with said radial plane containing said radially outwardly extending flat portion of said shroud means.
Claim 12
Dependent Claim
32 words
A heat exchange apparatus as set forth in claim 6, wherein said second plane is substantially coincident with said radial plane containing said radially outwardly extending flat portion of said shroud means.
Claim 13
Dependent Claim
377 words
A heat exchange apparatus comprising: a heat exchange means having front and rear faces; a shroud means including a forward section having forwardmost edge means arranged to encircle said rear face of said heat exchange means, and a rear exit shroud means having forwardmost edge means joined to rearwardmost edge means of said forward section, said exit shroud means including, in successive sections, a generally cylindrical, axially extending throat section, an annular, radially and axially extending, curved section, and an annular, generally radially extending flat portion; a rotatable axial flow, suction-type fan encircled by said rear exit shroud means having a plurality of circumferentially spaced impeller blades extending radially from a hub, each of said impeller blades having an effective axial width AW measured axially along the rotational axis of the fan between a first plane and a second plane, said planes being axially spaced and parallel with respect to each other and disposed substantially normal to the rotational axis of the fan, said first and second planes extending radially, respectively, through a point on the leading edge of each of the impeller blades at the tip region thereof and through a point on each of the trailing edges of the impeller blades also at the tip region thereof, said second plane being axially spaced from and on either axial side of a plane containing said annular, generally radially extending flat portion of said exit shroud means a distance of 12 percent or less of AW, and the following relationships exist: RF=AW/3 plus or minus 12 percent of AW, CF=AW/3 plus or minus 12 percent of AW, and R=2AW/3 plus or minus 12 percent of AW, where RF is the radial length of the radially extending flat portion, CF is the axial length of the cylindrical throat section, and R is the radius of curvature of the radial curved section; and air recirculation barrier means axially spaced rearwardly of said second plane a predetermined distance less than one half of the diameter of said fan for obstructing axial flow of air in a forward direction from the region axially rearwardly of said fan hub when said fan is rotated, said barrier means lying substantially in a plane spaced and substantially parallel with respect to said second plane.
Claim 14
Dependent Claim
377 words
A heat exchange apparatus comprising: a heat exchange means having front and rear faces; a shroud means including a forward section having forwardmost edge means arranged to encircle said rear face of said heat exchange means, and a rear exit shroud means having forwardmost edge means joined to rearwardmost edge means of said forward section, said exit shroud means including, in successive sections, a generally cylindrical, axially extending throat section, an annular, radially and axially extending, curved section, and an annular, generally radially extending flat portion; a rotatable axial flow, suction-type fan encircled by said rear exit shroud means having a plurality of circumferentially spaced impeller blades extending radially from a hub, each of said impeller blades having an effective axial width AW measured axially along the rotational axis of the fan between a first plane and a second plane, said planes being axially spaced and parallel with respect to each other and disposed substantially normal to the rotational axis of the fan, said first and second planes extending radially, respectively, through a point on the leading edge of each of the impeller blades at the tip region thereof and through a point on each of the trailing edges of the impeller blades also at the tip region thereof, said second plane being axially spaced from and on either axial side of a plane containing said annular, generally radially extending flat portion of said exit shroud means a distance of 12 percent or less of AW, and the following relationships exist: RF=AW/3 plus or minus 12 percent of AW, CF=AW/3 plus or minus 12 percent of AW, and R=2AW/3 plus or minus 12 percent of AW, where RF is the radial length of the radially extending flat portion, CF is the axial length of the cylindrical throat section, and R is the radius of curvature of the radial curved section; and air recirculation barrier means axially spaced rearwardly of said second plane a predetermined distance less than one half of the diameter of said fan for obstructing axial flow of air in a forward direction from the region axially rearwardly of said fan hub when said fan is rotated, said barrier means lying substantially in a plane spaced and substantially parallel with respect to said second plane.
Claim 15
Dependent Claim
32 words
A heat exchange apparatus as set forth in claim 11, wherein said second plane is substantially coincident with said radial plane containing said radially outwardly extending flat portion of said shroud means.
Claim 16
Dependent Claim
394 words
A heat exchange apparatus comprising: the heat exchange means having front and rear faces; a shroud means including a forward section having forwardmost edge means arranged to encircle said rear face of said heat exchange means, and a rear exit shroud means having forwardmost means joined to rearwardmost edge means of said forward section, said exit shroud means including, in successive sections, a generally cylindrical, axially extending throat section, an annular radially and axially extending, curved section, and an annular, generally radially extending flat portion; a rotatable, axial flow, suction-type fan encircled by said rear exit shroud means having a plurality of circumferentially spaced impeller blades extending radially from a hub, each of said impeller blades having an effective axial width AW measured axially along the rotational axis of the fan between a first plane and a second plane, said planes being axially spaced and parallel with respect to each other and disposed substantially normal to the totational axis of the fan, said first and second planes extending radially, respectively, through a point on each of the leading edges of the impeller blades at the radial tip region thereof and through a point on each of the trailing edges of the impeller blades also at the radial tip region thereof, said second plane being axially spaced from and on either axial side of a plane containing said annular, generally radially extending flat portion of said exit shroud means a distance of 12 percent or less of AW, and the following relationships exist: RF=AW/3 plus or minus 12 percent of AW, CF=AW/3 plus or minus 12 percent of AW, and R=2AW/3 plus or minus 12 percent of AW where RF is the radial length of the radially extending flat portion, CF is the axial length of the cylindrical throat section, and R is the radius of curvature of the radial curved section; and air recirculation barrier means axially spaced rearwardly of said second plane a predetermined distance less than one half of the diameter of said fan for obstructing axial flow of air in a forward direction from the region axially rearwardly of said fan hub when said fan is rotated, said air recirculation barrier means being generally in a form of a flat and substantially imperforate disk, said disk lying substantially in a radial plane spaced and parallel with respect to said second plane.
Claim 17
Dependent Claim
394 words
A heat exchange apparatus comprising: the heat exchange means having front and rear faces; a shroud means including a forward section having forwardmost edge means arranged to encircle said rear face of said heat exchange means, and a rear exit shroud means having forwardmost means joined to rearwardmost edge means of said forward section, said exit shroud means including, in successive sections, a generally cylindrical, axially extending throat section, an annular radially and axially extending, curved section, and an annular, generally radially extending flat portion; a rotatable, axial flow, suction-type fan encircled by said rear exit shroud means having a plurality of circumferentially spaced impeller blades extending radially from a hub, each of said impeller blades having an effective axial width AW measured axially along the rotational axis of the fan between a first plane and a second plane, said planes being axially spaced and parallel with respect to each other and disposed substantially normal to the totational axis of the fan, said first and second planes extending radially, respectively, through a point on each of the leading edges of the impeller blades at the radial tip region thereof and through a point on each of the trailing edges of the impeller blades also at the radial tip region thereof, said second plane being axially spaced from and on either axial side of a plane containing said annular, generally radially extending flat portion of said exit shroud means a distance of 12 percent or less of AW, and the following relationships exist: RF=AW/3 plus or minus 12 percent of AW, CF=AW/3 plus or minus 12 percent of AW, and R=2AW/3 plus or minus 12 percent of AW where RF is the radial length of the radially extending flat portion, CF is the axial length of the cylindrical throat section, and R is the radius of curvature of the radial curved section; and air recirculation barrier means axially spaced rearwardly of said second plane a predetermined distance less than one half of the diameter of said fan for obstructing axial flow of air in a forward direction from the region axially rearwardly of said fan hub when said fan is rotated, said air recirculation barrier means being generally in a form of a flat and substantially imperforate disk, said disk lying substantially in a radial plane spaced and parallel with respect to said second plane.
Claim 18
Dependent Claim
32 words
A heat exchange apparatus as set forth in claim 13, wherein said second plane is substantially coincident with said radial plane containing said radially outwardly extending flat portion of said shroud means.
Claim 19
Dependent Claim
37 words
A heat exchange apparatus as set forth in claim 13, wherein: said predetermined distance said air recirculation barrier means is axially spaced rearwardly of said second plane is about 15 percent of the diameter of said fan.
Claim 20
Dependent Claim
62 words
A heat exchange apparatus as set forth in claim 13, wherein: said radial flat portion has its radially outermost periphery defined by a circle; and said flat and substantially imperforate disk has its radially outermost periphery defined by a circle having substantially the same diameter as said circle defining the radially outermost periphery of said radial flat portion of said shroud means.
Claim 21
Dependent Claim
37 words
A heat exchange apparatus as set forth in claim 16, wherein: said predetermined distance said air recirculation barrier means is axially spaced rearwardly of said second plane is about 15 percent of the diameter of said fan.
Claim 22
Dependent Claim
24 words
A heat exchange apparatus as set forth in claim 17, wherein: said air recirculation barrier means is fixed with respect to said shroud means.
Claim 23
Dependent Claim
24 words
A heat exchange apparatus as set forth in claim 17, wherein: said air recirculation barrier means is rotatable in unison with said fan blades.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-11-12 | 1983-05-14 | 1983-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-11-12 | 1987-05-14 | 1987-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-11-12 | 1991-05-14 | 1991-11-13 | $7700.00 | Window Closed / Lapsed |