U.S. patent application number 10/044411 was filed with the patent office on 2002-08-01 for electric pump end cap with integrated electrical connection.
Invention is credited to Blass, James R., Hall, Phil, Keyster, Eric S., Meyer, Paul, Miller, Terry L..
Application Number | 20020102166 10/044411 |
Document ID | / |
Family ID | 26721516 |
Filed Date | 2002-08-01 |
United States Patent
Application |
20020102166 |
Kind Code |
A1 |
Keyster, Eric S. ; et
al. |
August 1, 2002 |
Electric pump end cap with integrated electrical connection
Abstract
A pump end cap preferably includes a plastic molding that is
shaped to include an external electrical socket and is internally
shaped to include electric motor brush placement holders. Electric
motor brushes are mounted on the holders. The electric motor
portion of the electronic pump assembly is completed when the end
cap is mated to an appropriate housing. By integrating a portion of
the electric motor into the pump end cap, the need for wires
extending from an electric motor terminal to the outside of the
pump housing is eliminated. The present invention preferably finds
application in fuel pump and filter assemblies used in conjunction
with diesel type internal combustion engines.
Inventors: |
Keyster, Eric S.; (Ashland
City, TN) ; Blass, James R.; (Bloomington, IL)
; Miller, Terry L.; (Morton, IL) ; Hall, Phil;
(Fairfield, IL) ; Meyer, Paul; (Alton,
IL) |
Correspondence
Address: |
Michael B. McNeil
Liell & McNeil Attorneys PC
P.O. Box 2417
Bloomington
IN
47402
US
|
Family ID: |
26721516 |
Appl. No.: |
10/044411 |
Filed: |
January 10, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60265371 |
Jan 31, 2001 |
|
|
|
Current U.S.
Class: |
417/371 ;
417/410.1 |
Current CPC
Class: |
F02M 37/048 20130101;
F02M 37/44 20190101; F04D 5/002 20130101; F04D 13/06 20130101; F04D
29/628 20130101 |
Class at
Publication: |
417/371 ;
417/410.1 |
International
Class: |
F04B 039/02 |
Claims
What is claimed is:
1. An electric pump end cap comprising: a plastic molding with an
external face separated from an internal face by a circumferential
side surface, and said external face including an electrical
connector socket shape, and said internal face including at least
one electric motor brush placement holder and defining a portion of
a fluid passage.
2. The electric pump end cap of claim 1 wherein said side surface
of said plastic molding includes at least one housing retention
recess.
3. The electric pump end cap of claim 2 including a first conductor
partially positioned in said plastic molding and being exposed
through said external face within said socket shape and through
said internal face; and a second conductor partially positioned in
said plastic molding and being exposed through said external face
within said socket shape and through said internal face.
4. The electric pump end cap of claim 3 including first and second
electric motor brushes supported by said first and second brush
placement holders, respectively.
5. The electric pump end cap of claim 4 wherein said fluid passage
includes said plastic molding defining a flow passage extending
between said internal face and one of said side surface and said
external face.
6. The electric pump end cap of claim 5 wherein said side surface
includes a cylindrical portion through which said flow passage
opens; and said at least one housing retention recess includes an
annular groove positioned between said external face and said
cylindrical portion.
7. The electric pump end cap of claim 6 wherein said internal face
includes a motor shaft support recess.
8. The electric pump end cap of claim 7 wherein said internal face
includes at least one motor alignment guide surface.
9. An electric pump assembly comprising: a housing; an end cap
attached to said housing to define an internal cavity and including
a plastic molding with an external face separated from an internal
face by a circumferential side surface, and said external face
including an electrical connector socket, and said internal face
having mounted thereon first and second electric motor brushes, and
first and second conductors at least partially positioned in said
plastic molding and extending between said brushes and said
electrical connector socket; a partial electric motor positioned in
said internal cavity in contact with said first and second electric
motor brushes; a fluid pump positioned in said internal cavity and
being operably coupled to said electric motor; and at least one of
said housing and said end cap defining an inlet and an outlet.
10. The electric pump assembly of claim 9 wherein said end cap
defines at least one housing retention recess; and a portion of
said housing being deformed into said housing retention recess.
11. The electric pump assembly of claim 10 wherein said at least
one housing retention recess includes an annular groove; and an
annular end portion of said housing being deformed into said
annular groove.
12. The electric pump assembly of claim 10 wherein said plastic
molding defines a flow passage extending between said internal face
and one of said side surface and said external face.
13. The electric pump assembly of claim 5 wherein said side surface
includes a cylindrical portion in contact with an inner surface of
said housing and through which said flow passage opens.
14. The electric pump assembly of claim 13 wherein said partial
electric motor includes a rotating shaft received in a motor shaft
support recess that is a portion of said internal face.
15. The electric pump assembly of claim 14 wherein said internal
face includes at least one motor alignment guide surface mated to
said partial electric motor.
16. The electric pump assembly of claim 15 wherein at least one of
said housing and said end cap define an exposed snap ring
groove.
17. A method of assembling an electric pump comprising the steps
of: attaching electric motor brushes to a plastic end cap;
extending electrical conductors from an external face of said end
cap to said electric motor brushes; positioning a pump and a
partial electric motor in a housing; and completing an electric
motor by mating said end cap to said housing.
18. The method of claim 17 including a step of attaching said
housing to said end cap at least in part by deforming a portion of
said housing.
19. The method of claim 18 wherein said mating step includes a step
of aligning a guide surface on said end cap with a mating surface
on said partial electric motor.
20. The method of claim 18 wherein said mating step includes
inserting a rotatable shaft of said partial electric motor into
motor shaft support recess defined by said end cap.
Description
RELATION TO OTHER APPLICATION
[0001] This application claims priority to provisional application
number 60/265,371, filed Jan. 31, 2001, and entitled Electric Pump
End Cap With Integrated Electrical Connection.
TECHNICAL FIELD
[0002] The present invention relates generally to electric pump
assemblies, and more particularly to a plastic molded end cap for a
pump assembly that includes an integrated electric motor
component.
BACKGROUND
[0003] Although electric fuel pump and filter assemblies have long
been known in the art, engineers continue to seek ways to improve
their designs. For instance, there is almost always room to improve
reliability and decrease cost. One area in which reliability can
generally be improved is by reducing part count and reducing the
number of electrical connections and associated wiring necessary to
bring electric power to an electric motor that is often positioned
deep inside a housing at a relatively inaccessible location. In
some instances, it is desirable that such assemblies not be
serviceable in order to further reduce reliability concerns that
can occur due to improper servicing of a nonserviceable component.
Thus, there are often several conflicting problems when there is a
desire to simultaneously reduce costs, improve reliability and
include design features that render a nonserviceable component
difficult to impossible to dismantle.
[0004] The present invention is directed to these and other
problems associated with electric pump assemblies.
SUMMARY OF THE INVENTION
[0005] In one aspect, an electric pump end cap includes a plastic
molding with an external face separated from an internal face by a
circumferential side surface. The external face includes an
electrical connector socket shape. The internal face includes at
least one electric motor brush placement holder and defines a
portion of a fluid passage.
[0006] In another aspect, an electric pump assembly includes an end
cap attached to a housing to define an internal cavity. The end cap
includes a plastic molding with an external face separated from an
internal face by a circumferential side surface. The external face
includes an electrical connector socket, and the internal face has
mounted thereon first and second electric motor brushes. First and
second conductors are at least partially positioned in the plastic
molding and extend between the brushes and the electrical connector
socket. A partial electric motor is positioned in the internal
cavity in contact with the first and second electric motor brushes.
A fluid pump is positioned in the internal cavity and operably
coupled to the electric motor. At least one of the housing and the
end cap define an inlet and an outlet.
[0007] In still another aspect, a method of assembling an electric
pump includes a step of attaching electric motor brushes to a
plastic end cap. Electrical conductors are extended from an
external face of the end cap to the electric motor brushes. Next, a
pump and a partial electric motor are positioned in a housing. The
electric motor is completed by mating the end cap to the
housing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIGS. 1a-1b are isometric and front views, respectively, of
a fuel pump and filter assembly for an internal combustion engine
according to one aspect of present invention;
[0009] FIG. 2a is a left side view of a pump assembly according to
the present invention;
[0010] FIG. 2b is a sectioned side diagrammatic view of the pump
assembly as viewed along section lines A-A of FIG. 2a;
[0011] FIG. 2c is a right side view of the pump assembly;
[0012] FIG. 2d is a partial sectioned side view of a pump
housing/end cap deformation attachment according to one aspect of
the present invention;
[0013] FIGS. 3a-3b are isometric and bottom views, respectively, of
an end cap assembly according to a preferred embodiment of the
present invention;
[0014] FIGS. 4a-4b are a pair of isometric views of a plastic
molding according to another aspect of the present invention;
[0015] FIG. 5 is an isometric view of a conductor and brush
assembly according to the present invention; and
[0016] FIGS. 6a-6b are a pair of isometric views of a plastic
molding according to another embodiment of the present
invention.
DETAILED DESCRIPTION
[0017] Referring to FIGS. 1a and 1b, a fuel pump and filter
assembly 1 includes a housing 2 within which is positioned an
electric pump 10 and a filter 3. This design is preferably not
serviceable, meaning that it is preferable that the housing include
features that prevent the electric pump assembly 10 from being
removed, serviced and then replaced in housing 2. However, it might
be desirable to allow a portion of the housing 2 open in order to
replace filter 3 with a fresh filter during regular scheduled
maintenance. The housing 2 defines an air vent 4, a fuel inlet 6
and a fuel outlet 7, all of which preferably include quick connect
shapes in order to ease in the installation of the pump and filter
assembly 1 between a fuel tank and an internal combustion engine.
Housing 2 also defines a pump opening 5 within which electric pump
10 is installed, preferably irreversibly. Finally, pump 10 includes
an electrical connector socket 42 to also ease in the installation
in connecting the pump to an appropriate electrical power source.
While the present invention has and is being illustrated in the
context of a fuel pump and filter assembly, those skilled in the
art will appreciate that the present invention could find potential
application in processing other fluids besides fuel, and could find
potential application outside of pumps used in conjunction with
internal combustion engines.
[0018] Referring now in addition to FIGS. 2a-2d, the structure of
electric pump 10 will be described. Electric pump 10 includes a
partial electric motor/pump assembly 12 a metallic can shaped
housing 14 and an end cap 16. In order to make the pump and filter
assembly 1 less serviceable, end cap 16 preferably includes a snap
ring groove 40 that mates with a snap ring to a receiving groove
defined by housing 2 in a conventional manner. Furthermore, the
snap ring is preferably concealed from view at least in part by the
inclusion of cover tabs 49 that tend to keep the snap ring
concealed when pump assembly 10 is installed as shown in FIGS. 1a
and 1b. Also, tabs 49 also provide orientation, as the two are not
the same size.
[0019] Can shaped housing 14 is preferably made from a suitable
sheet metal material that can be deformed to provide a suitable and
relatively irreversible attachment to end cap 16. When mated as
shown in FIG. 2b, housing 14 and end cap 16 define an internal
cavity 26 that includes a fluid passage 22 defined in part by
plastic molding 15, which makes up the bulk of end cap 16. Housing
14 defines an inlet opening 20 and an outlet opening 18 that both
open to internal cavity 26. Thus, when in operation, fuel is drawn
into inlet opening 20 and exits pump assembly 10 via outlet 18
under the action of the electric motor and pump assembly 11/12.
Those skilled in the art will appreciate that inlet 20 and outlet
18 could be relocated to any suitable location, including but not
limited to the possibility of plastic molding 15 defining one or
both of the inlet and outlet.
[0020] In this preferred embodiment, housing 14 includes a flared
end 24 that facilitates the mating of housing 14 with end cap 16.
The attachment is preferably completed by deforming a portion of
housing 14 into at least one retention recess 36 defined by plastic
molding 15. In the preferred embodiment illustrated, retention
recess 36 includes an annular groove and the annular end portion 24
of housing 14 is deformed in a conventional manner, such as by use
of a roller, into annular retention groove 36 as shown in FIG. 2d.
This attachment strategy renders pump assembly 10 relatively
unserviceable by making it difficult to impossible to disengage
housing 14 from end cap 16 without damaging one or both
components.
[0021] Referring in addition to FIGS. 3a and 3b, end cap 16
includes a plastic molding 15 that includes an electrical socket 42
that is electrically connected to a pair of motor brushes 46 via a
suitable conductor 43 (FIG. 5). When end cap 16 is mated to housing
14, a cylindrical portion 31 comes in contact with inner surface 13
of housing 14. Furthermore, end cap 16 includes at least one motor
alignment guide surface 39 that mates into a recess in partial
electric motor/pump assembly 12 in order to insure that brushes 46
are appropriately located on the armature of electric motor 11. In
addition, motor alignment guide 39 helps to insure that a flow
passage 35 defined by plastic molding 15 aligns with outlet 18 so
that fluid passage 22 can communicate with outlet 18. In addition,
plastic molding 15 includes a shaft support recess 38 that receives
a portion of rotatable shaft 21 and also acts as a journal bearing
for the same. Recess 38 could house a brass or other material
journal bearing for increased run dry protection.
[0022] Referring to FIGS. 4a and 4b, plastic molding 15 is shaped
to include an external surface 30 separated from an internal
surface 32 by a circumferential side surface 34. Side surface 34 is
preferably shaped to include cylindrical portion 31 that closely
matches the inside diameter of can shaped housing 14 (FIG. 2) and
an annular retention groove 36 into which a flared end 24 of
housing 14 is deformed in order to secure end cap 16 to housing 14.
External face 30 is preferably molded to include a suitable
electrical connector socket shape 42, which can be any type known
in the art. Internal face 32 is preferably formed to include shaft
support recess 38, a pair of brush placement holders 17 and a pair
of inductor holders 33 (FIG. 3). Preferably, a conductor and motor
brush assembly 43 of the type shown in FIG. 5 is attached to
plastic molding 15 in a suitable manner, such as by the use of
shunts, to produce an assembled end cap as shown in FIGS. 3a and
3b. Conductors 43 are preferably positioned so that a pin portion
44 is exposed through external face 30 in socket 42, and brushes 46
are supported by brush holders 17. Preferably, conductors 43
include a conductor pin 41 that is attached to a wire 48, which is
wound around an inductor core 45 and electrically connected to
electric motor brush 46 by a brush support 47. Brush support 47 and
inductor core 45 are received in and supported by brush placement
holders 17 and inductor holders 33, respectively. Thus, end cap 16
carries at least one essential electric component necessary to
complete an electric motor. In addition, the electrical connection
made to socket 42 is done without having to connect wire between a
separate motor terminal and a socket, and thus the integrated
design eliminates the need for terminals on the electric motor.
[0023] Referring to FIGS. 6a and 6b, a plastic molding 115
according to an alternative embodiment of the present invention is
much like the plastic molding 15 described earlier except that it
defines a flow passage 35 extending between its external face 130
and its internal face 132. This is an alternative to the side port
openings 18 and 35 defined by housing 14 and end cap 16,
respectively. The flow passage 135 preferably includes a quick
connect shape 137 that is similar to that shown in relation to
FIGS. 1a and 1b. Like the earlier embodiment, plastic molding 115
is shaped to include brush placement holders 117 on the internal
face and an electrical connector socket shape 142 on its external
face. Inductor holders can also be part of this style connector.
Like the earlier embodiment, external face 130 is separated from
internal face 132 by a circumferential side surface 134 which
includes at least one cylindrical portion 131 and preferably
includes an annular retention groove 136. This embodiment also can
include additional grooves for placement of O rings if it is
desired to make the connection between the end cap and the housing
fluid tight. Finally, like the earlier embodiment, internal face
132 includes a shaft support recess that receives and supports the
rotatable shaft of the electric motor. It might also be desirable
to insert a brass or other type of journal bearing for improved
life running without fuel. If plastic molding 115 were substituted
for plastic molding 15 described earlier and installed to create a
complete pump assembly 10, flow passage 135 would open directly
into, and define a portion of, flow fluid passage 22. In all other
aspects, plastic molding 115 and plastic molding 15 are
substantially similar.
[0024] Industrial Applicability
[0025] The pump assembly 10 preferably utilizes a partial electric
motor/pump assembly 12 of a type manufactured by Airtex Products of
Fairfield, Ill. This subassembly is then positioned within housing
14 as shown in FIG. 2b. Next, the plastic molding 15 or 115 is
formed and electrical conductors are extended between the external
face and electric motor brushes 46 that are attached to the end cap
16. Next, the electric motor 11 is completed by mating the end cap
to the housing 14 as shown in FIG. 2b. In order to insure that
complete mating as shown in FIG. 2b, it is preferably necessary to
mate alignment guide surface 39 with an appropriate mating surface
on the partial electric motor/pump assembly 12. This feature
insures that electric brushes 46 will be properly located in the
complete assembly and that flow passage 35 will align with outlet
18. In addition, the mating of the end cap 16 with housing 14
includes having shaft support recess 38 receive an end portion of
rotatable shaft 21. This preferably is accomplished by making the
centerline of shaft support recess 38 concentric with the
centerline of cylindrical portion 34 that comes in contact with the
inner surface 13 of housing 14. The end cap 16 is attached to
housing 14 preferably by deforming an annular end portion 24 into
an annular retention recess 36 formed on this side surface 34 of
plastic molding 15. Those skilled in the art will appreciate that,
in the event that plastic molding 115 is substituted for plastic
molding 15, the assembly procedure is substantially identical.
[0026] The present invention has the potential advantage of
integrating the electrical connections for the electric motor into
the pump end cap in a way that reduces the need to extend wires or
other conductors between electric motor terminals and the outside
of the pump assembly. This is accomplished by mounting at least one
electric motor component, such as brushes, on the pump end cap. In
addition, by including appropriate geometry, one can be assured
that the electric motor will be properly assembled when the
appropriate mating surfaces come in contact with one another as
illustrated in FIG. 2b. This structural strategy can allow for a
reduction in part count and a substantial increase in reliability
by eliminating electrical connections (between a terminal and an
electric socket) that can eventually be problematic and/or lead to
pump failure. By integrating some of the electric motor components
into the end cap, cost can be reduced. Those skilled in the art
will appreciate that other aspects, objects and advantages of this
invention can be obtained from a study of the drawings, the
disclosure and the appended claims.
* * * * *