U.S. patent application number 09/736816 was filed with the patent office on 2002-06-20 for through-flow blower with cooling fan.
This patent application is currently assigned to Ametek, Inc.. Invention is credited to Morelli, Anthony J..
Application Number | 20020076341 09/736816 |
Document ID | / |
Family ID | 24961413 |
Filed Date | 2002-06-20 |
United States Patent
Application |
20020076341 |
Kind Code |
A1 |
Morelli, Anthony J. |
June 20, 2002 |
Through-flow blower with cooling fan
Abstract
A through-flow blower assembly includes a housing that carries a
motor assembly. The motor assembly has a stator, and a rotor that
rotates a shaft when energized. The rotor has openings
therethrough. A fan shell has an axial opening and is coupled to
the housing. At least one rotating fan is carried by the shaft The
rotating fan draws working air through said axial opening and
exhausts the working air through an exhaust port of the housing.
The rotating fan has a diameter larger than the rotor. A cooling
fan is attached to the rotor and includes a fan disc and a fan
ring. The fan disc is connected to the fan ring by a plurality of
blades, said fan ring having an eye that is directly adjacent the
rotor openings. The cooling fan has a diameter no larger than said
rotor. As the rotor rotates, the cooling fan draws a portion of the
working air over the motor assembly for cooling purposes.
Stationary fans may be carried by the fan shell if more than one
rotating fan is provided.
Inventors: |
Morelli, Anthony J.;
(Alliance, OH) |
Correspondence
Address: |
Ray L. Weber
Renner, Kenner, Greive, Bobak, Taylor & Weber
First National Tower, Fourth Floor
Akron
OH
44308
US
|
Assignee: |
Ametek, Inc.
|
Family ID: |
24961413 |
Appl. No.: |
09/736816 |
Filed: |
December 14, 2000 |
Current U.S.
Class: |
417/423.8 ;
417/423.14 |
Current CPC
Class: |
F04D 29/5806 20130101;
F04D 25/0613 20130101; F04D 17/164 20130101 |
Class at
Publication: |
417/423.8 ;
417/423.14 |
International
Class: |
F04B 017/00 |
Claims
What is claimed is:
1. A through-flow blower comprising; a working air fan assembly
having an axial opening; a housing coupled to said working air fan
assembly, said housing having an exhaust port; a motor assembly
carried in said housing and rotating said working air fan assembly,
said motor having a stator and a rotor, said rotor having at least
one opening therethrough; and a cooling fan connected to said
rotor, such that as said rotor rotates cooling air is drawn through
said opening.
2. The blower according to claim 1, further comprising; a shaft
coupled to said rotor, said working air fan assembly and said
cooling fan.
3. The blower according to claim 1, wherein said cooling air
comprises; a fan disc having a shaft opening; a fan ring having an
eyelet; and a plurality of fan blades connecting said fan disc to
said fan ring, said eyelet positioned adjacent said rotor
opening.
4. The blower according to claim 3, wherein said rotor comprises;
an end wall having said rotor opening; and a side wall extending
from said end wall.
5. The blower according to claim 4, wherein said rotor has an outer
diameter larger than an outer diameter of said cooling fan.
6. A through-flow blower assembly comprising; a housing having a
tangential exhaust port; a motor assembly carried by said housing,
said motor assembly having a stator and a rotor, said rotor
rotating a shaft when said motor assembly is energized, said rotor
having openings therethrough; a fan shell having an axial opening;
at least one rotating fan carried by said shaft, said at least one
rotating fan drawing working air through said axial opening and
exhausting the working air through said exhaust port, said at least
one rotating fan having a diameter larger than said rotor; and a
cooling fan having a fan disc and a fan ring, said fan disc
connected to said fan ring by a plurality of blades, said fan ring
having an eye that is directly adjacent said rotor openings, said
cooling fan having a diameter no larger than said rotor.
7. The assembly according to claim 6, further comprising: a
plurality of rotating fans carried by said shaft; and a
predetermined number of stationary fans carried by said fan shell,
wherein said predetermined number is one less than the number of
said plurality of rotating fans.
8. The assembly according to claim 7, wherein said stationary fans
are interleaved between said rotating fans.
Description
TECHNICAL FIELD
[0001] The invention herein resides generally in the art of
through-flow blowers. More particularly, the present invention
relates to a cooling fan that piggy backs the motor assembly
included in the through-flow blower.
BACKGROUND ART
[0002] Through-flow blowers are generally known for drawing in air
which is then reoriented into another direction. These blowers
typically draw the air through a series of interleaved motor-driven
rotating fans and stationary fans to enhance the force of the air
generated by the blower. This air may be used as working air such
as with vacuum cleaners, furnace blowers or the like. The air, once
drawn into the blower, typically swirls within the shell of a
housing and is exhausted tangentially outwardly.
[0003] Currently internal turbulence within the attached motor
housing, as a result of the internal features of the housing, is
relied upon to dissipate the heat generated by the motor windings.
Although this turbulence is effective in most instances for cooling
the motor windings, in certain instances excessive heat is known to
be generated. This excessive heat can lead to motor damage and
related structural failures. In one application it has been found
that the temperature between the windings and the ambient air can
be as high as 96.degree. C. Therefore, there is a need to
facilitate/enhance the air flow over the motor windings for motors
used in through-flow blowers.
DISCLOSURE OF INVENTION
[0004] In light of the foregoing, it is a first aspect of the
present invention to provide a through-flow blower with a cooling
fan.
[0005] Another aspect of the present invention is to provide a
through-flow blower as set forth above, which couples a fan
assembly to a motor.
[0006] Still a further aspect of the present invention is to
provide a through-flow blower assembly, as set forth above, in
which the motor is a brushless configuration having a stator
assembly and a rotor assembly and wherein the rotor assembly has at
least one opening therethrough.
[0007] Yet a further aspect of the present invention is to provide
a through-flow blower, as set forth above, in which a cooling fan
is coupled to the rotor assembly so as to draw cooling air through
the opening and over the motor windings to dissipate heat in a more
efficient manner.
[0008] Yet a further aspect of the present invention is to provide
a through-flow blower, as set forth above, wherein the cooling fan
has an outer diameter that is no larger than the outer diameter of
the rotor.
[0009] The foregoing and other objects of the present invention,
which shall become apparent as the detailed description proceeds,
are achieved by a through-flow blower comprising; a working air fan
assembly having an axial opening; a housing coupled to the working
air fan assembly, the housing having an exhaust port; a motor
assembly carried in the housing and rotating the working air fan
assembly, the motor having a stator and a rotor, the rotor having
at least one opening therethrough; and a cooling fan connected to
the rotor, such that as the rotor rotates cooling air drawn through
the opening.
[0010] Other aspects of the present invention are attained by a
through-flow blower assembly comprising; a housing having a
tangential exhaust port; a motor assembly carried by the housing,
the motor assembly having a stator and a rotor, the rotor rotating
a shaft when the motor assembly is energized, the rotor having
openings therethrough; a fan shell having an axial opening; at
least one rotating fan carried by the shaft, the at least one
rotating fan drawing working air through the axial opening and
exhausting the working air through the exhaust port, the at least
one rotating fan having a diameter larger than the rotor; and a
cooling fan having a fan disc and a fan ring, the fan disc
connected to the fan ring by a plurality of blades, the fan ring
having an eye that is directly adjacent the rotor openings, the
cooling fan having a diameter no larger than the rotor.
[0011] These and other objects of the present invention, as well as
the advantages thereof over existing prior art forms, which will
become apparent from the description to follow, are accomplished by
the improvements hereinafter described and claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] For a complete understanding of the objects, techniques and
structure of the invention, reference should be made to the
following detailed description and accompanying drawings,
wherein:
[0013] FIG. 1 is a side elevational view, in partial cross-section,
of a through-flow blower according to the present invention;
[0014] FIG. 2 is a frontal view of the through-flow blower;
[0015] FIG. 3 is an enlarged view showing a cooling fan attached to
a shaft of the through-flow blower;
[0016] FIG. 4 is an elevational view of a stator assembly carried
by the blower;
[0017] FIG. 5 is a plan view of a rotor assembly carried by the
blower;
[0018] FIG. 6 is a plan view of a cooling fan; and
[0019] FIG. 7 is an edge view of the cooling fan.
BEST MODE FOR CARRYING OUT THE INVENTION
[0020] Referring now to the drawings and more particularly to FIGS.
1-5, it can be seen that a through-flow blower with a cooling fan
is designated generally by the numeral 10. Generally, the blower 10
includes a housing 12 which contains a motor assembly designated
generally by the numeral 14. A pair of power leads 16 extend from
the housing 12 to provide energy to the motor 14 from a power
source (not shown). A shaft 20 is coupled to the motor assembly 14
in a manner well known in the art.
[0021] A fan assembly, designated generally by the numeral 22, is
rotated by the shaft 20 and is connected thereto by a washer 24 and
a nut 26. The fan assembly 22 includes a fan shell 28 which
partially encloses the fan assembly and is secured to the housing
12 by press fit or appropriate fasteners. The fan shell 28 provides
an axial opening 30 for drawing in working air and/or cooling air
as needed. The fan assembly 22 includes at least one rotating fan
32 and in the preferred embodiment three rotating fans are
employed. Interleaved between each rotating fan 32 is a stationary
fan 34 that is carried by an interior surface of the fan shell 28
in a manner well known in the art. As the rotating fans 32 rotate,
air is drawn in through the axial opening 30 and then radially
dispersed by each fan. Upon exiting the vanes of rotating fans 32,
the air becomes pressurized and is then forced through the
stationary fan 34 to be received by the next-in-line rotating fan
32. It will be appreciated that any number of rotating fans 32 and
stationary fans 34 may be used in a blower 10 as described herein.
Typically, there will always be one less stationary fan than
rotating fan. As shown in FIG. 1, there are three rotating fans and
two stationary fans. If there is only one rotating fan, there is no
need for a stationary fan.
[0022] The housing 12 includes a tangentially extending exhaust
port 38 through which the working air is exhausted. The port 38 is
at an end of the housing 12 opposite the end with the axial
opening. It will be appreciated that as the working air exits the
rotating fan 32 furthest from the axial opening 30, the air swirls
around within the housing and once pressurized exits the exhaust
port 38. The housing 12 includes an axially extending hub 40 which
extends in a direction toward the fan assembly 22. The hub 40
includes an end bearing 42 which rotatably receives one end of the
shaft 20 in a manner well known in the art. A washer 44 may be
interposed between the bearing 42 and the housing 12. A fan end
bearing 46 is carried in a distal end of the hub 40, away from the
housing 12, to provide a second point of rotatable contact with the
shaft. A plurality of internal stand-offs 50 are provided about the
periphery of the housing 12 to support and carry a stator assembly
52. The stator assembly 52 includes a stator plate 54 which carries
circuitry and related connections between the leads 16 and of the
stator windings 56. Extending from the stator plate 54 is a stator
sidewall 58 which has a plurality of openings 60.
[0023] A rotor assembly 64, which is secured to the shaft 20 and
which causes the shaft to rotate when the windings are energized,
is rotatably received within the stator assembly 52. The rotor
assembly includes a sidewall 66 which is partially enclosed at one
end thereof by an end wall 68. The end wall 68 includes at least
one opening 70. A coupling 72 secures the rotor assembly 64 to the
shaft 20.
[0024] A cooling fan, designated generally by the numeral 80, is
carried by the shaft 12 and is positioned adjacent to the end wall
68. As best seen in FIGS. 6 and 7, the cooling fan includes a fan
disc 82, which has a shaft hole 83, and a fan ring 84 which has an
eyelet 86. Interconnecting the fan disc 82 to the fan ring 84 are a
plurality of curvilinear vanes 88. The cooling fan 80 is positioned
so that the fan ring 84 is aligned directly adjacent the rotor end
wall 68. Accordingly, the eyelet 86 is directly aligned with at
least a portion of the openings 70. A cooling fan spacer 90 is
interposed between the fan disc 82 and the next adjacent rotating
fan 32. Working fans spacers 92 are radially positioned between the
rotating fans and stationary fans 32, 34 and the shaft 20.
Accordingly, a gap 94 is formed by the spacer 90 between the
cooling fan 80 and the most adjacent rotating fan 32.
[0025] In operation, when the motor assembly 14 is energized,
rotation of the rotor 64 and the shaft 20 is initiated. Rotation of
the shaft turns the rotating fans 32 so as to draw working air in
through the axial opening 30. This working air is then expelled by
the rotating fans radially whereupon it is dispersed by the
stationary fans 34. It is then received by the next adjacent
rotating fan 32 and the above process is repeated until the working
air is expelled out the exhaust port 38. In the past, this working
air had been relied upon to provide cooling airflow near but not
directly over, the motor windings and allow for dissipation of heat
generated thereby. To significantly improve the cooling of the
motor windings, inclusion of the cooling fan 80 functions to draw
cooling air directly over the motor windings so as to dissipate
heat. In particular, the rotation of the rotor and the attached
cooling fan 80 draws in a portion of the working air before it is
exhausted out the port 38 and then recirculates air in an axial
direction essentially opposite that of the working air flow. This
air is then pulled directly over the windings. When this cooling
air is expelled from the fan 80, it is exhausted by the vanes 88 so
as to mix with the working air flow so that it can be exhausted
through the exhaust port 38.
[0026] The advantages of the present invention are readily apparent
based upon the foregoing description. In particular, use of the
cooling fan coupled to the rotor functions to pull air through and
over the motor windings so as to dissipate and remove heat
generated thereby. The cooling air is expelled out from the cooling
fan to mix with the working air flow. This is accomplished by
coupling the cooling fan to the rotor so as to redirect the air
flow from an axial direction to a radial direction. Moreover, the
outer diameter of the cooling fan is such that it does not
interfere with operation of the blower or require excessive work to
be performed by the motor. Moreover, the outer diameter of the
cooling fan is smaller in diameter than the rotating fans 32 or the
rotor 64 so that the primary flow of the working air is not
impeded. Inclusion of the cooling fan with the blower referred to
in the Background Art reduces the difference between the ambient
temperature and winding temperature from about 96.degree. C. to
about 53.degree. C.
[0027] Thus, it can be seen that the objects of the invention have
been satisfied by the structure and its method for use presented
above. While in accordance with the Patent Statutes, only the best
mode and preferred embodiment has been presented and described in
detail, it is to be understood that the invention is not limited
thereto or thereby. Accordingly, for an appreciation of true scope
and breadth of the invention, reference should be made to the
following claims.
* * * * *