U.S. patent application number 12/473841 was filed with the patent office on 2009-12-03 for cooling airflow electric motor-driven pump.
This patent application is currently assigned to GMJ Design Group, LLC. Invention is credited to Lu HANKUN, Mei XINGCAN.
Application Number | 20090297373 12/473841 |
Document ID | / |
Family ID | 41380093 |
Filed Date | 2009-12-03 |
United States Patent
Application |
20090297373 |
Kind Code |
A1 |
XINGCAN; Mei ; et
al. |
December 3, 2009 |
COOLING AIRFLOW ELECTRIC MOTOR-DRIVEN PUMP
Abstract
An improved cooling airflow electric motor-driven pump,
particularly adapted for pumping condensate from refrigeration and
air conditioning systems includes a reservoir body, a reservoir
cover supporting an electric motor directly connect to a
centrifugal pump impeller at one end of the motor rotor shaft and
to an open radial blade blower wheel at the opposite end of the
motor rotor shaft. The motor is mounted on the reservoir cover and
a motor cover mounted on the reservoir covers defines an
aerothermodynamically matched blower wheel shroud and cooling air
inlet and discharge ports for the flow of cooling air across the
motor and associated electronic controls.
Inventors: |
XINGCAN; Mei; (ZhongShan
City, CN) ; HANKUN; Lu; (JiangMen City, CN) |
Correspondence
Address: |
LUCAS & MERCANTI, LLP
475 PARK AVENUE SOUTH, 15TH FLOOR
NEW YORK
NY
10016
US
|
Assignee: |
GMJ Design Group, LLC
Lake Worth
FL
|
Family ID: |
41380093 |
Appl. No.: |
12/473841 |
Filed: |
May 28, 2009 |
Current U.S.
Class: |
417/423.8 |
Current CPC
Class: |
F04D 25/082 20130101;
F24F 13/222 20130101; F04B 53/08 20130101; F04D 13/06 20130101;
F04D 29/588 20130101 |
Class at
Publication: |
417/423.8 |
International
Class: |
F04B 53/08 20060101
F04B053/08; F04B 17/03 20060101 F04B017/03 |
Foreign Application Data
Date |
Code |
Application Number |
May 28, 2008 |
CN |
200810098770.9 |
Claims
1. An improved cooling airflow electric motor-driven pump
comprising: a reservoir body including a reservoir chamber for
collecting liquid; a reservoir cover releasably connected to and
disposed over the reservoir body and including a fluid inlet port
for conducting liquid to the reservoir chamber; an open radial
blade blower wheel for cooling air flow; an electric motor mounted
on the reservoir cover including a first shaft part drivingly
connected to a pump impeller and a second shaft part drivingly
connected to the blower wheel; and a motor cover disposed over the
motor and the blower wheel, the motor cover being releasably
mounted on the reservoir cover, the motor cover including a blower
wheel shroud aerothermodynamically matched to the blower wheel, an
air scoop proximately located adjacent to the blower wheel shroud
and disposed in a second part of the motor cover, and a means
forming at least one cooling airflow flue disposed in a third part
of the motor cover and formed between the air scoop second part and
a fourth part of the motor cover.
2. The improved cooling airflow pump of claim 1 wherein: the blower
wheel shroud of the motor cover comprises a generally cylindrical
part and is provided with a plurality of spaced apart tangential
slots extending generally vertically about the blower wheel shroud
periphery forming cooling air discharge ports and adjacent to the
blower wheel when the motor cover is disposed on the reservoir
cover to provide for cooling air discharge from a cooling air
discharge chamber formed by the air scoop second part of the motor
cover.
3. The improved cooling airflow pump of claim 1 wherein: the fourth
part of the motor cover comprises a generally rectangular part and
is provided with a plurality of vertically extending spaced apart
slots forming cooling air inlet ports disposed in the fourth part
of the motor cover and spaced from the reservoir cover.
4. The improved cooling airflow pump of claim 1 wherein: the blower
wheel shroud of the motor cover is integrally joined to the air
scoop second part of the motor cover and the fourth part of the
motor cover and the blower wheel shroud of the motor cover forms a
cover for at least of a portion of the motor.
5. The improved cooling airflow pump of claim 1 wherein: the
cooling air flow flue third part of the motor cover is integrally
joined to the air scoop second part of the motor cover and the
fourth part of the motor cover, and the cooling air flow flue third
part of the motor cover forms a cover for at least the float
control electronics for controlling operation of the motor.
6. An improved cooling airflow electric motor-driven pump
comprising: a reservoir body including a reservoir chamber for
collecting liquid; a reservoir cover releasably connected to and
disposed over the reservoir body; an open radial blade blower wheel
for cooling air flow; an electric motor mounted on the reservoir
cover including a first vertically extending shaft part drivingly
connected to a pump impeller and a second vertically shaft part
drivingly connected to the blower; and a motor cover disposed over
the motor and the blower wheel, the motor cover being releasably
mounted on the reservoir cover, the motor cover including a
generally cylindrical first part of the motor cover forming a
cooling air shroud and covering the blower wheel, a plurality of
spaced apart tangential slots extending generally vertically formed
in the first part of the motor cover adjacent to the blower wheel
when the motor cover is disposed on the reservoir cover to provide
for cooling air discharge from the cooling air shroud formed by the
first part of the motor cover, an air scoop disposed in a second
part of the motor cover, a means forming at least one cooling
airflow flue disposed in a third part of the motor cover, a
generally rectangular fourth part of the cover, and a plurality of
vertically extending spaced apart slots forming cooling air inlet
ports disposed in the fourth part of the motor cover and spaced
from the reservoir cover.
7. The improved cooling airflow pump of claim 6 wherein: the first
part of the motor cover is integrally joined to the second and
fourth parts of the motor cover, and the first part of the motor
cover forms a cover for at least a portion of the motor.
8. The improved cooling airflow pump of claim 6 wherein: the third
part of the motor cover is integrally joined to the second and
fourth parts of the motor cover, and the third part of the motor
cover forms a cover for at least the float control electronics for
controlling operation of the motor.
9. An improved cooling airflow electric motor-driven pump
comprising: a reservoir body including a reservoir chamber for
collecting liquid; a reservoir cover releasably connected to and
disposed over the reservoir body; a fluid inlet port for conducting
liquid to the reservoir chamber, an open radial blade blower wheel
for cooling air flow; an electric motor mounted on the reservoir
cover including a first shaft part drivingly connected to a pump
impeller and a second shaft part drivingly connected to the blower
wheel; and a motor cover disposed over the motor and the blower
wheel, the motor cover being releasably mounted on the reservoir
cover, the motor cover including a plurality of spaced apart
tangential slots extending generally vertically forming cooling air
discharge ports and disposed in a first generally cylindrical part
of the motor cover, and a plurality of vertically extending spaced
apart slots forming cooling air inlet ports disposed in a second
part of the motor cover and spaced from the reservoir cover.
10. The improved cooling airflow pump of claim 9 wherein: the first
part of the motor cover is integrally joined to the second part,
and the first part of the motor cover forms a cooling air discharge
shroud containing at least part of the motor and the blower
wheel.
11. The improved cooling airflow pump of claim 9 wherein: the
second part of the motor cover is integrally joined to the first,
and the second part of the motor cover forms a cover for at least
the float control electronics for controlling operation of the
motor.
12. An improved cooling airflow device for an electric motor-driven
condensate pump, the device comprising: a cover having a generally
cylindrical first part, a generally teardrop-shaped second part, a
generally trapezoidal third part and a generally rectangular fourth
part; a plurality of spaced apart tangential slots extending
generally vertically disposed in the first part of the cover and
forming cooling air discharge ports; a plurality of vertically
extending spaced apart slots disposed in the fourth part of the
motor cover and forming cooling air inlet ports; and an open radial
blade blower wheel aerothermodynamically coupled to the cooling air
inlet and discharge ports to optimize airflow across the electric
motor to dissipate heat.
13. The improved cooling airflow device of claim 12 wherein: the
first part of the motor cover is integrally joined to the second
and fourth parts of the motor cover, and the first part of the
motor cover forms a cooling air discharge shroud containing at
least part of the motor and the blower wheel.
14. The improved cooling airflow device of claim 12 wherein: the
third part of the motor cover is integrally joined to the second
and fourth parts of the motor cover, and the third part of the
motor cover forms a cover for at least the float control
electronics for controlling operation of the motor.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to the field of liquid
pumping, and more particularly but not by way of limitation, to an
improved cooling airflow electric motor-driven condensate pump.
BACKGROUND OF THE INVENTION
[0002] A condensate pump is used especially in the field of heating
and air conditioning, as well as in many other applications, where
liquid condensate is generated such as when moisture or humidity is
present in the ambient atmosphere. Condensate runoff from cooled
surfaces, such as from coils in refrigeration or air conditioning
units, must be collected and pumped to a remote location for
disposal. The condensate pump typically comprises a reservoir, a
float for detecting the level of condensate water in the reservoir,
and a centrifugal pump driven by an electric motor controlled by
the float for pumping water out of the reservoir to the remote
location.
[0003] Condensate pumps are often located in extreme environments
and subject to moisture, heat and contamination or fouling.
Moreover, condensate pumps are frequently installed in inaccessible
locations where maintenance is difficult, and therefore reliability
over many years is necessary. Cost considerations have demanded
economy of manufacture, and many commercial units are typically
fabricated to be as inexpensive and compact as possible.
[0004] For many years, condensate pump assemblies of the general
type described above have been available for the collection and
disposal of condensate water. Such devices which must reliably
operate largely unattended over a span of years have experienced
premature failure due to excessive heating of the motor and the
associated float control electronics from inadequate cooling air
flow. Several prior art devices have attempted to overcome this
limitation.
[0005] One such prior art device is taught by U.S. Pat. No.
6,322,326 issued to Davis et al. In '326, a plurality of vertical
air outlet ventilation slots and a plurality of horizontal air
inlet ventilation slots are provided in the motor cover to
facilitate air ventilation. A turbine air fan, more particularly a
squirrel cage, is connected to one end of the motor and effects an
air flow directioned to cool the electric motor.
[0006] Another prior art device is taught by U.S. Pat. No.
7,252,482 issued to Walker et al. In '482, a plurality of
horizontal slots form the cooling air discharge ports and a
plurality of vertical slot, disbursed about the motor cover, form
the cooling air inlet ports. A centrifugal cooling air fan,
preferably of the squirrel cage type, is connected to one end of
the motor for propelling cooling air through the discharge
ports.
[0007] Both prior art devices utilize a squirrel cage fan and, more
specifically, a forward curved multi-vane blower wheel. See 58 in
'326 and 54 in '482. Impeller Fan, Squirrel Cage, Multi-vane,
Runner and Disc are all used to describe fans or blowers depending
what country a person is from. Typically a blower is a centrifugal
device with some type of wheel and a fan is an axial device with a
propeller. There are six basic types of blower wheels defined as
shrouded radial blade, open radial blade, open paddle wheel,
backward inclined (with flat blades or airfoil blades), forward
curved multi-vane (squirrel cage), and backward curved radial.
[0008] Forward curved multi-vane blower wheels (or squirrel cages)
are a mechanical device having a wheel comprised of a number of
blades mounted around a hub with two end plates. They are typically
used for forced cooling air at slower speeds or for moving large
volumes of air at lower pressures. They require the lowest speed of
any centrifugal blower wheels to move a given amount of air which
limits the speed of the condensate pump since both the fan and pump
are directly coupled to the motor. This means the blower wheel and
pump speed are identical to the motor's rotational speed. Forward
curved multi-vane blower wheels can only operate in one direction
due to the fact that the blades are curved forward in the direction
of rotation.
[0009] Centrifugal blowers with forward-curved blades are not
aerodynamically designed to be the most efficient. Instead, they
are chosen for their ability to deliver relatively high flow rates
for rather restrictive packaging requirements. A centrifugal fan or
blower typically draws air from the side of the fan wheel, through
the wheel, turns it 90 degrees and accelerates the air due to
centrifugal force as it flows over the fan blades and exits out
through the discharge of the housing. For example, in '482, air
enters from side face 54a, is turned 90 degrees by fan blades 54b
and discharges out the side at periphery 54c.
[0010] Wheels with slightly modified geometries may perform quite
differently in terms of flow efficiency and noise. The objective of
the blower wheel design is to provide the best wheel to meet the
requirements of air flow performance, noise, structural integrity
and cost. The present invention improves upon this prior art by
aerothermodynamically matching the blower wheel to a blower wheel
shroud disbursed about the motor cover.
OBJECTS OF THE INVENTION
[0011] It is the object of this invention to provide an electric
motor-driven pump having improved cooling air flow characteristics
to dissipate heat away from the motor and the electronic controls
for controlling operation of the motor. It is also an objective of
this invention to provide a motor cover and cooling air port
locations coupled to an open radial blade blower wheel to optimize
air flow across the motor to dissipate heat in the most thermally
efficient manner. It is a further object of this invention to
provide an improved cooling air flow electric motor-driven pump
that is economical to build and easily mounted within refrigeration
and air conditioning systems.
SUMMARY OF THE INVENTION
[0012] The object of the present invention are obtained by
utilizing an open radial blade blower wheel in which the blades
extend straight out from the hub and are perpendicular to the
direction of the wheel's rotation, like a paddle wheel. Open radial
blade blower wheels are generally the least efficient of the
centrifugal blower wheels and a typically not used for general
ventilation. However, by coupling the open radial blade blower
wheel to a blower wheel shroud, the present invention achieves
improved flow performance and noise characteristics.
[0013] In addition, open radial blade blower wheels are more
contaminant tolerant and less sensitive to fouling due to solids
build-up on the blades which would potentially plug the air inlet
ports (54a in '482) in a forward curved multi-vane blower wheel (or
squirrel cage) used in the prior art. Open radial blade blower
wheels can rotate in either direction which further facilitates
dispersing debris from the blades. They are typically more robust
then squirrel cage designs and therefore more reliable. This
reliability is enhanced with the addition of the blower wheel
shroud. They can operate at higher speeds because of their
robustness which allows the condensate pump to operate more
effectively. Open radial blade blower wheels reduce the flow
induced noise generated by the blower while retaining and possibly
improving the cooling air flow performance for a given speed.
[0014] Broadly speaking, the invention can be defines as an
improved cooling airflow electric motor-driven pump comprising:
[0015] a reservoir body including a reservoir chamber for
collecting liquid;
[0016] a reservoir cover releasably connected to and disposed over
the reservoir body and including a fluid inlet port for conducting
liquid to the reservoir chamber;
[0017] an open radial blade blower wheel for cooling air flow;
[0018] an electric motor mounted on the reservoir cover including a
first shaft part drivingly connected to a pump impeller and a
second shaft part drivingly connected to the blower wheel;
[0019] and a motor cover disposed over the motor and the blower
wheel, the motor cover being releasably mounted on the reservoir
cover, the motor cover including a blower wheel shroud
aerothermodynamically matched to the blower wheel, an air scoop
proximately located adjacent to the blower wheel shroud and
disposed in a second part of the motor cover, and a means forming
at least one cooling airflow flue disposed in a third part of the
motor cover and formed between the air scoop second part and a
fourth part of the motor cover.
[0020] The blower wheel shroud of the motor cover comprises a
generally cylindrical part and is provided with a plurality of
spaced apart tangential slots extending generally vertically about
the blower wheel shroud periphery forming cooling air discharge
ports and adjacent to the blower wheel when the motor cover is
disposed on the reservoir cover to provide for cooling air
discharge from a cooling air discharge chamber formed by the air
scoop second part of the motor cover. The orientation of the
tangential slots in the blower wheel shroud is aligned with the air
flow exit angle from the blower wheel blades to enhance the
aerodynamics of the cooling air flow through the cooling air
discharge ports. This has the added benefit of reducing the overall
noise of the unit as the disruption of airflow is minimized as it
exits and enters the motor cover.
[0021] An air scoop is proximately located adjacent to the blower
wheel shroud and disposed in a second part of the motor cover. The
air scoop is a teardrop shaped configuration when view from the top
and facilitates the air flow transition from the cooling airflow
flue disposed in a third part of the motor cover to the blower
wheel.
[0022] The cooling airflow flue is disposed in a third part of the
motor cover. It is shaped to act as a natural draft mechanism to
facilitate the air flow from the plurality of vertically extending
spaced apart slots forming cooling air inlet ports disposed in the
fourth part of the motor cover across the electric motor windings
and the associated electronic controls for controlling operation of
the motor to the air scoop.
[0023] The fourth part of the motor cover comprises a generally
rectangular part and is provided with a plurality of vertically
extending spaced apart slots forming cooling air inlet ports
disposed in the fourth part of the motor cover and spaced from the
reservoir cover.
[0024] The blower wheel shroud of the motor cover is integrally
joined to the air scoop second part of the motor cover and the
fourth rectangular part of the motor cover. The blower wheel shroud
forms a cover for at least of a portion of the motor and the blower
wheel.
[0025] The cooling air flow flue third part of the motor cover is
integrally joined to the air scoop second part of the motor cover
and the fourth part of the motor cover. The cooling air flow flue
third part of the motor cover forms a cover for at least the float
control electronics for controlling operation of the motor.
[0026] The shape of the motor cover and the location of the inlet
and discharge ports coupled to an open radial blade blower wheel
optimize the air flow across the motor and associated electronic
controls to dissipate heat in the most thermally efficient
manner.
[0027] Those skilled in the art will further appreciate the
above-mentioned advantages and superior features of the pump of the
present invention, together with other important aspects thereof,
upon reading the detailed description which follows in conjunction
with the drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 is a perspective view of a modular condensate pump
assembly constructed in accordance with the prior art as taught by
U.S. Pat. No. 6,322,326;
[0029] FIG. 2 is an elevational view, in cross section, of the
condensate pump assembly of FIG. 1;
[0030] FIG. 3 is a perspective view of an electric motor-driven
pump constructed in accordance with the prior art as taught by U.S.
Pat. No. 7,252,482;
[0031] FIG. 4 is a section view taken generally along the line 3-3
of FIG. 1;
[0032] FIG. 5 is a perspective view of an improved cooling airflow
electric motor-driven pump in accordance with the present
invention;
[0033] FIG. 6 is a front elevational view of the pump shown in FIG.
5;
[0034] FIG. 7 is a section view taken generally along the line 7-7
of FIG. 6; and
[0035] FIG. 8 is a plan view of the pump shown in FIG. 7 with the
motor shroud or cover removed.
DETAILED DESCRIPTION OF THE DRAWINGS
[0036] FIGS. 1 and 2 illustrate modular condensate pump assembly 10
constructed in accordance with the prior art as taught by U.S. Pat.
No. 6,322,326. In FIG. 1, plurality of vertical air outlet
ventilation slots 38 and plurality of horizontal air inlet
ventilation slots 38A are provided in motor cover 16 to facilitate
air ventilation. As shown in FIG. 2, turbine air fan 58 is a
squirrel cage type connected to one end of motor 48 and effects an
air flow directioned to cool electric motor 48.
[0037] FIGS. 3 and 4 illustrate electric motor-driven pump 10 in
accordance with the prior art as taught by U.S. Pat. No. 7,252,482.
In FIG. 3, plurality of horizontal slots 25g form the cooling air
discharge ports and plurality of vertical slot 25a-25f, disbursed
about motor cover 24, form the cooling air inlet ports. As shown in
FIG. 4, centrifugal cooling air fan 54 is preferably of a squirrel
cage type and is connected to one end of motor 32 for propelling
cooling air through discharge ports 25g.
[0038] FIG. 5 illustrates improved cooling airflow electric
motor-driven pump 10 in accordance with the invention. Pump 10 is
particularly adapted for transferring liquids, such as condensate
generated by air conditioning and refrigeration systems from
condensate collection pans or the like, to an integral reservoir of
pump 10 comprising open top hollow body 12 and forming reservoir
chamber 13, see FIG. 7. Reservoir body 12 is of generally
rectangular configuration and is adapted to support generally
planar, removable cover member 14, as illustrated. Fluid inlet
ports 16, 17 and 18 are provided in cover member 14 for selective
connection to a fluid inlet conduit, not shown. Fluid is discharged
from pump 10 by way of discharge conduit 22, FIGS. 5 through 8,
which is particularly adapted for forcible connection to a flexible
fluid discharge hose, not shown. Reservoir cover 14 is releasably
connected to reservoir body 12 by opposed depending elastically
deflectable latch members, not shown. Reservoir body 12 is provided
with spaced apart integral mounting brackets 12b, FIGS. 5, 6 and
7.
[0039] As shown in FIGS. 5 and 6, pump 10 includes motor shroud or
cover 24 which is of unique construction and advantageously
encloses electric motor 32, FIG. 7, to be described further herein
for driving pump impeller 40 of pump 10. Motor cover 24 further
forms an enclosure for electronic controls 66 for operating pump
motor 32 and an enclosure for open radial blade blower wheel 54
which is directly connected to pump motor rotor 36. Motor cover 24
is formed as a hollow shell-like member and includes blower wheel
shroud 26 aerothermodynamically matched to blower wheel 54, air
scoop 27 proximately located adjacent to blower wheel shroud 26 and
disposed in a second part of motor cover 24, and means forming at
least one cooling airflow flue 28 disposed in a third part of motor
cover 24 and formed between air scoop 27 and fourth part 30 of
motor cover 24.
[0040] Blower wheel shroud 26 comprises a generally cylindrical
part and is provided with plurality of spaced apart tangential
slots 31 extending generally vertically about the periphery of
blower wheel shroud 26 forming cooling air discharge ports and
adjacent to blower wheel 54 when motor cover 24 is disposed on
reservoir cover 14 to provide for cooling air discharge from
cooling air discharge chamber 26a formed by air scoop 27. As shown
in FIG. 6, tangential slots 31 are orientated to align with the air
flow exit angle from blower wheel blades 54b to enhance the
aerodynamics of the cooling air flow through the cooling air
discharge ports. Air scoop 27 is proximately located adjacent to
blower wheel shroud 26 and disposed in a second part of motor cover
24. Air scoop 27 is a teardrop shaped configuration when view from
the top and facilitates the air flow transition from cooling
airflow flue 28 disposed in a third part of motor cover 24 to
blower wheel 54. Cooling airflow flue 28 is disposed in a third
part of motor cover 24. Cooling airflow flue 28 is shaped to act as
a natural draft mechanism to facilitate the air flow from plurality
of vertically extending spaced apart slots 25 forming cooling air
inlet ports disposed in fourth part 30 of motor cover 24 across
electric motor 32 windings and associated electronic controls 66 to
air scoop 27. Fourth part 30 of motor cover 24 comprises a
generally rectangular part and is provided with plurality of
vertically extending spaced apart slots 25 forming cooling air
inlet ports disposed in fourth part 30 and spaced from reservoir
cover 14.
[0041] Blower wheel shroud 26 is integrally joined to air scoop 27
and fourth rectangular part 30 of motor cover 24. Blower wheel
shroud 26 forms cover for at least of a portion of motor 32 and
blower wheel 54. Cooling air flow flue 28 is also integrally joined
to air scoop 27 and fourth rectangular part 30 of motor cover 24.
Cooling air flow flue 28 forms a cover for at least control
electronics 66. Parts 26, 27, 28 and 30 are preferably formed of a
suitable molded plastic which is the case for reservoir cover 14
and reservoir body 12 also. As shown in FIGS. 5 and 6, motor cover
24 is preferably joined to reservoir cover 14 by spaced apart tabs
24a, which are insertable in cooperating slots 14b, FIG. 8, formed
in reservoir cover 14. Accordingly, molded motor cover 24 may be
easily snapped into and out of engagement with reservoir cover
14.
[0042] Referring to FIG. 7, pump 10 is provided with electric motor
32, suitably mounted within motor cover 24 and on reservoir cover
14. Motor 32 includes a rotor 34 suitably mounted in spaced apart
bearings, not shown. Rotor 34 is operably connected to opposed
coaxial rotatable motor output shaft parts 36 and 38. Shaft part 38
depends into reservoir 12 and is connected to centrifugal pump
impeller 40. Impeller 40 is disposed in a chamber 42 formed by a
pump housing part 44 which is suitably connected to the underside
of reservoir cover 14 and includes reservoir sub-chamber 45 in
communication with chamber 13 by way of vertical slot-like fluid
inlet ports 46. Pump housing 44 is also provided with impeller
inlet passage 47 and removable cover 48 to allow access to pump
impeller 40. Pump discharge conduit or fitting 22 is threadedly
connected to housing 44 at threaded bore 50. Suitable spring biased
fluid discharge check valve 52 is interposed housing 44 and pump
discharge conduit 22 to prevent back-flow from a pump discharge
line, not shown, into chamber 42. As shown in FIGS. 5, 6 and 8,
alternate fluid inlet ports 16 and 17 for a pump reservoir inlet
line, not shown, are provided in cover member 14 and are formed
with so-called knock-out plugs, as illustrated in FIGS. 5 and 6.
Motor shaft part 36 supports and is drivingly connected to a open
radial blade blower wheel 54, FIGS. 7 and 8, for rotation upon
energization of motor 32. Accordingly, at any time that pump 10 is
operating to discharge fluid from reservoir chamber 13, open radial
blade blower wheel 54 is operating to drawing cooling air into an
interior space 57, FIG. 7, of motor cover 24 through cooling air
inlet ports 25 to provide a uniformly distributed flow of cooling
air over motor 32 and electronic controls 66. Open radial blade
blower wheel 54 is preferably made of impact resistant plastic,
fabricated steel, stainless steel or cast aluminum, and includes
impeller blades 54b, FIG. 7. Cooling air propelled by blower wheel
54 is discharged at periphery 54c of the blower wheel 54 and then
through cooling air discharge ports 31. Thanks to the provision of
air scoop 27, blower wheel 54 is operable to reside in space 26a,
FIG. 7, which provides, in essence, an airflow discharge chamber
which is in communication with the cooling air discharge ports
31.
[0043] The construction and operation of pump 10 is believed to
readily understandable to those of ordinary skill in the art based
on the foregoing description. Conventional engineering plastics may
be used to fabricate parts such as reservoir body 12, reservoir
cover 14, motor cover 24, pump reservoir housing 44 and cover 48
and the discharge fitting 22. Impeller 40 and blower wheel 54 may
also be formed of molded plastic although other engineering
materials normally used for pump and fan construction may be
utilized. Thanks to the shape of motor cover 24 and the location of
inlet ports 25 and discharge ports 31 coupled to open radial blade
blower wheel 54 the air flow is optimized across motor 32 and
electronic controls 66 to dissipate heat in the most thermally
efficient manner. Hence, improved motor cooling air flow is
obtained relatively easily and in an uncomplicated arrangement.
[0044] Those skilled in the art will recognize the above-described
features and advantages of the invention and that various
substitutions and modifications may be made without departing from
the scope and spirit of the appended claims.
REFERENCE CHARACTERS
[0045] 10 Pump [0046] 12 Reservoir Body [0047] 12a Integral
Mounting Tab [0048] 13 Reservoir Chamber [0049] 14 Reservoir Cover
[0050] 14b Slots [0051] 16 Fluid Inlet Port [0052] 17 Fluid Inlet
Port [0053] 18 Fluid Inlet Port [0054] 22 Discharge Conduit [0055]
24 Motor Cover [0056] 24a Tab [0057] 25 Cooling Air Inlet Port
[0058] 26 Cylindrical Part [0059] 26a Air Scoop Chamber [0060] 27
Air Scoop [0061] 28 Air Flue [0062] 30 Rectangular Part [0063] 31
Cooling Air Discharge Port [0064] 32 Electric Motor [0065] 34 Motor
Rotor [0066] 36 Motor Shaft [0067] 38 Motor Shaft [0068] 40
Centrifugal Impeller [0069] 42 Chamber [0070] 44 Pump Housing
[0071] 45 Sub-chamber [0072] 46 Slot [0073] 47 Impeller Inlet
Passage [0074] 48 Cover [0075] 50 Threaded Bore [0076] 52 Check
Valve [0077] 54 Blower Wheel [0078] 54b Blade [0079] 54c Periphery
[0080] 66 Electronic Controls
* * * * *