U.S. patent application number 11/500788 was filed with the patent office on 2007-02-15 for tool-free adjustable clean out assembly for a pump.
This patent application is currently assigned to EnviroTech Pumpsystems, Inc.. Invention is credited to Kim M. Arnold.
Application Number | 20070036643 11/500788 |
Document ID | / |
Family ID | 37742703 |
Filed Date | 2007-02-15 |
United States Patent
Application |
20070036643 |
Kind Code |
A1 |
Arnold; Kim M. |
February 15, 2007 |
Tool-free adjustable clean out assembly for a pump
Abstract
A clean out assembly for a centrifugal pump, particularly, for
example, a self-priming-type of centrifugal pump, is structured to
provide easy adjustment of the clean out assembly and axial
movement of a wear plate in proximity to the impeller of the pump
without the need for tools to effect such movement of the wear
plate and clean out assembly.
Inventors: |
Arnold; Kim M.; (Draper,
UT) |
Correspondence
Address: |
MORRISS O'BRYANT COMPAGNI, P.C.
136 SOUTH MAIN STREET
SUITE 700
SALT LAKE CITY
UT
84101
US
|
Assignee: |
EnviroTech Pumpsystems,
Inc.
|
Family ID: |
37742703 |
Appl. No.: |
11/500788 |
Filed: |
August 8, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60707006 |
Aug 10, 2005 |
|
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|
Current U.S.
Class: |
415/131 |
Current CPC
Class: |
F04D 29/167 20130101;
F04D 29/708 20130101; F04D 29/622 20130101; F04D 29/628 20130101;
F04D 29/4286 20130101 |
Class at
Publication: |
415/131 |
International
Class: |
F01D 5/02 20060101
F01D005/02 |
Claims
1. A centrifugal pump having a clean out assembly, comprising: a
pump casing housing an impeller and having an opening oriented
axially to the eye of the impeller for receiving a clean out
assembly; a clean out assembly having an end cover attached to and
spaced from a wear plate for positioning in proximity to said
impeller; securement apparatus for securing said clean out assembly
to said pump housing; and at least two adjustment elements
positioned on said end cover for providing tool-free axial
adjustment of said wear plate relative to said impeller, said
adjustment elements being separately operable from said securement
apparatus such that said adjustment elements effect axial movement
of said wear plate without removal of said securement apparatus
from said end cover.
2. The centrifugal pump of claim 1 wherein said adjustment elements
are configured with handles for effecting tool-free movement of
said adjustment elements for axial adjustment of said end
cover.
3. The centrifugal pump of claim 2 wherein said adjustment elements
are positioned between said end cover and said pump casing.
4. The centrifugal pump of claim 3 wherein said adjustment elements
further comprise a threaded shaft threading received through said
end cover.
5. The centrifugal pump of claim 1 wherein said adjustment elements
further comprise indicia for determining the amount of axial
adjustment made to said end cover.
6. The centrifugal pump of claim 1 wherein said securement
apparatus further comprises stud bolts connected to said pump
casing which are receivable through corresponding openings formed
in said end cover, and further wherein said securement apparatus
comprise a hand nut for too-free adjustment of said securement
apparatus.
7. A centrifugal pump having a clean out assembly, comprising: a
pump casing housing an impeller and having an opening oriented
axially to the eye of the impeller for receiving a clean out
assembly; a clean out assembly having an end cover attached to and
spaced from a wear plate; a plurality of threaded studs securing
said end cover to said pump casing by means of a hand bolt
connected to said threaded studs; adjustment elements each
comprising a threaded shaft for threaded attachment through said
end cover and a handle formed to said threaded shaft for effecting
tool-free rotation of said threaded shaft by hand, said threaded
shaft being positioned in contact with said pump casing.
8. The centrifugal pump of claim 7 further comprising indicia for
determining the amount of axial adjustment of said end cover.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a non-provisional application claiming
priority to provisional patent application Ser. No. 60/707,006
filed Aug. 10, 2005.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to self-priming centrifugal pumps,
and relates specifically to a clean-out assembly for a self-priming
pump that facilitates access to the interior of the pump and axial
adjustment of the wear plate relative to the impeller.
[0004] 2. Description of Related Art
[0005] Self-priming centrifugal pumps are well-known and frequently
used in industries where processing fluids with entrained solids is
required. Self-priming pumps, also known as trash pumps, are
characterized as having a casing which houses a suction chamber and
a separation chamber divided by a wall or plenum. An impeller
positioned in a volute section of the pump receives fluid from the
suction chamber and delivers it by centrifugal action into the
separation chamber where it is eventually expelled through an
outlet.
[0006] The impeller of self-primer pumps are generally of the open
type, meaning that the impeller has a rear shroud, but an open eye
into which fluid flows from the suction chamber. In order for the
pump to operate most efficiently, the impeller must be positioned
as close as possible to the wall of the volute casing of the pump
to minimize recirculation and leakage of fluid out and around the
impeller. To accomplish that, a wear plate is typically positioned
between the volute casing and the open or suction side of the
impeller. The wear plate is positioned in very close proximity to
the impeller vanes to assure efficient pump operation.
[0007] As the pump is operated, especially in the processing of
fluids with entrained solids, the vanes of the impeller and/or the
wear plate can become worn down by the solids and the resulting gap
or clearance between the impeller vanes and wear plate causes the
pump to operate with less efficiency. It then becomes necessary to
adjust the distance or clearance between the impeller and the wear
plate to assure a close fit therebetween.
[0008] Pump manufacturers have dealt with this problem in the prior
art by providing various means by which the clearance between the
impeller and the wear plate can be adjusted as needed. In old prior
art systems, an adjustment was provided for axial movement of the
rotating assembly (i.e., impeller and drive shaft) relative to a
stationary wear plate or pump casing. However, such adjustment
means involved the need to correspondingly adjust the drive shaft
relative to the motor, and involved other compensatory adjustments
to structural elements of the pump.
[0009] In certain types of pumps, exemplified by self-primer pumps,
a clean out assembly is provided which serves two essential
purposes. First, the clean out assembly provides access to the eye
of the impeller through the suction chamber and provides a
convenient means for removing solids or other debris that may have
clogged the impeller. Second, the clean out assembly has provided a
supporting structure for the wear plate and, consequently, a means
for adjusting the axial distance between the wear plate and
impeller.
[0010] In presently known clean out assemblies having means for
adjusting the wear plate, the adjustment means or devices are
complicated, usually requiring several adjustment and securement
devices, and all require tools for removing and/or adjusting the
several elements to effect an adjustment of the wear plate. As a
result, adjusting the wear plate can be difficult and time
consuming, and the several elements that comprise the adjustment
mechanism increase the cost of the pump.
[0011] Thus, it would be advantageous to provide a clean out
assembly that provides adjustment of the wear plate, but which
requires no tools to effect the adjustment of the wear plate or to
remove the clean out assembly for servicing of the pump, thereby
also simplifying manufacture of the pump and reducing the cost of
manufacture.
BRIEF SUMMARY OF THE INVENTION
[0012] In accordance with the present invention, a clean out
assembly for a pump, particularly a self-primer-type centrifugal
pump, is structured to provide support for a wear plate and to
provide a tool-free means for not only axially adjusting the wear
plate relative to the impeller of the pump, but to facilitate
removal of the clean out assembly for servicing the impeller of the
pump. As used herein, "tool-free" means that no tools are required
to effect movement or adjustment of the described elements of the
clean out assembly and that such movement is achieved by using
one's hand to effect such adjustment or movement.
[0013] The clean out assembly of the present invention generally
comprises an end cover which provides support for a wear plate and
is positioned to cover the access opening in a centrifugal pump
axial to the eye of the impeller. The end cover supports a wear
plate that is positioned in close proximity to the impeller when
the end cover is secured in place within the pump casing. The end
cover is attached is the pump casing by securement apparatus.
[0014] The end cover, and thus the wear plate, is axially
adjustable relative to the pump casing and the impeller by
adjustment elements that operate separately from the securement
apparatus for attaching the end cover to the pump casing and, in an
especially suitable embodiment may be spaced from the securement
apparatus. By providing adjustment elements operably separate from
the securement means, axial adjustment of the wear plate is
significantly simplified over conventionally-known clean out
assemblies for pumps.
[0015] The adjustment elements comprise a threaded shaft that is
threadingly positioned through openings in the end cover. The
adjustment elements also have a handle which can be turned by hand
to effect adjustment of the end cover relative to the pump casing,
and thus effect axial adjustment of the wear plate relative to the
impeller. The securement apparatus for attaching the end cover to
the pump casing are also each provided with hand nuts that enable
tightening of the securement apparatus by hand. No tools are
required to effect attachment or adjustment of the end cover
relative to the pump casing, as is conventional in the prior
art.
[0016] The simplified structures of the present clean out assembly
enable axial adjustment of the end cover and wear plate without the
need for tools, and enable axial adjustment without removal of any
parts. The configuration of the present clean out assembly
effectively reduces the manufacturing and operating costs of the
pump.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0017] In the drawings, which illustrate what is currently
considered to be the best mode for carrying out the invention:
[0018] FIG. 1 is a perspective view of a prior art pump
illustrating conventional structure for a clean out assembly;
[0019] FIG. 2 is a view in cross section of the prior art clean out
assembly shown in FIG. 1;
[0020] FIG. 3 is a perspective view of a pump illustrating the
clean assembly of the present invention; and
[0021] FIG. 4 is a view in cross section of the clean assembly of
the present invention as shown in FIG. 3.
DETAILED DESCRIPTION OF THE INVENTION
[0022] By way of comparison, a prior art clean out assembly 10 is
illustrated in FIGS. 1 and 2 which comprises, in general, an end
cover 12 and a supporting ring 14 spaced from the end cover 12 by a
plurality of stanchions 16. The supporting ring 14 provides a means
for attachment thereto of a wear plate 18, which is connected to
the supporting ring 14 by screws 20. The clean out assembly 10 fits
into an opening 22 formed in the pump casing 24 so that the wear
plate 18 is positioned adjacent the impeller 25, as best seen in
FIG. 2.
[0023] In the prior art pump of FIG. 1, the clean out assembly 10
is connected to the pump casing 24 by a plurality of threaded studs
26 that extend through holes 28 formed in the end cover 12. The end
cover 12 is secured in place by hand nuts 30 that tighten onto the
threaded studs 26.
[0024] The means for adjusting the axial position of the wear plate
18 relative to the impeller is also associated with the means for
attaching the end cover 12 to the pump casing 24. Specifically, a
threaded adjustment member 34 threads into each opening 28 in the
end cover 12 and slips onto the threaded stud 26. The adjustment
member 34 has a hexagonally-configured head the corners of which
engage with teeth formed in a central opening 38 of a locking
member 36. The opening 38 of the locking member 36 is sized to
receive the head of the adjustment member 34.
[0025] The locking member 36 is normally bolted to the end cover 12
by the positioning of a locking bolt 40 and washer 42 through an
opening 44 in the locking member 36. The locking bolt 40 then
threads into an opening 46 in the end cover 12. When the axial
position of the wear plate 18 is to be adjusted (i.e., the axial
position of the clean out assembly is to be adjusted relative to
the pump casing 24), the hand nut 30 must first be removed from the
threaded stud 26. The locking member 36 is then removed from the
end cover 12 by using a first tool to loosen and remove the locking
bolt 40 and nut 44.
[0026] Each adjustment member 34 is then rotated a selected amount
to move the end cover 12 toward the pump casing 24. A tool
different from the tool used to remove the locking bolt 40 is used
for that process. Once the adjustment members 34 are rotated the
desired amount, the locking member 36 is replaced about the head of
the adjustment member 34 and is locked in place by securement of
the locking bolt 40 into place. Each of these steps requires
various tools for effecting the adjustment, and the adjustment
involves manipulation of several structural elements, all of which
results in time-consuming and costly servicing and added cost for
manufacturing of the pump.
[0027] The clean out assembly 50 of the present invention, shown in
FIGS. 3 and 4, solves the problems encountered with prior art clean
out assemblies by providing a simplified and tool-free means for
attaching the clean out assembly to the pump casing and for
effecting adjustment of the wear plate. Further, the clean out
assembly of the present invention provides means for attachment of
the end cover to the pump casing which is separate from the axial
adjustment structure, thereby eliminating the need to remove
structural elements associated with attachment of the end cover as
is required in the prior art.
[0028] The clean out assembly 50 of the present invention comprises
an end cover 52 and a supporting ring 54 to which a wear plate 56
is attached by some means, such as bolts 58. The supporting ring
54, and thus the wear plate 56, is spaced from the end cover 52 by
a plurality of spacer columns 60. The clean out assembly 50 fits
into an opening 62 in the pump casing 64 in the conventional manner
to position the wear plate 56 in very close proximity to the
impeller 61, as best seen in FIG. 4.
[0029] The end cover 52 of the present invention is secured
adjacent the shoulder 66 surrounding the opening 62 in the pump
casing 64 by securement apparatus comprising a plurality of
threaded stud bolts 68 that extend through openings 70 in the end
cover 52. A threaded hand nut 72 is attachable to each stud bolt 68
providing a means for tightening the end cover 52 to the pump
casing 64.
[0030] Axial adjustment of the wear plate 56 in the present
invention is effected by providing two or more adjustment elements
78 that comprise a threaded shaft 80 and a handle 82. The threaded
shaft 80 of the adjustment element 78 is threaded through a
threaded opening 84 in the end cover 52. As best seen in FIG. 4,
the adjustment element 78 is set so that the terminal end 86 of the
threaded shaft 80 seats against the shoulder 66 of the pump casing
64. As will become apparent for axial adjustment purposes, the end
cover 52 is initially positioned relative to the shoulder 66 of the
opening 62 in the pump casing 64 such that a space 88 is provided
between the shoulder 66 and the end cover 52.
[0031] When adjustment of the wear plate 56 is required (i.e., when
the wear plate 56 needs to be brought into closer proximity to the
impeller 61), the hand nuts 72 on the stud bolts 68 are loosened
slightly by hand to allow movement of the end cover 52. The handle
82 of each adjustment element 78 is then rotated by hand to effect
movement of the end cover 52 in a direction toward the pump casing
64, and thus effect axial movement of the wear plate 56 toward the
impeller 61. Movement of the end cover 52 is accomplished by the
fact that the threaded shaft 80 of the adjustment elements 78 are
threaded into the threaded openings 84 in the end cover 52;
consequently, rotation of the handles 82 causes the end cover 52 to
move in a direction toward the impeller 61.
[0032] Once the wear plate 56 is adjusted to the desired point of
proximity to the impeller 61, the hand nuts 72 are then turned by
hand to tighten the end cover 52 again to the pump casing 64. The
adjustment elements 78 of the invention are structured with
self-locking threads that lock the adjustment elements 78 into
place after movement. However, a locking element of known structure
may also be employed to secure the adjustment elements 78 in place.
Indicia 90 may also be provided on the adjustment elements 78 to
calibrate the amount by which the axial adjustment is made.
[0033] It can be appreciated from the foregoing disclosure that the
clean out assembly of the present invention provides an improved
and simplified means of securing the clean out assembly to the pump
casing and effecting axial adjustment of the wear plate relative to
the impeller, while reducing the costs of manufacture and operation
of the pump. The structure, configuration and placement of the
adjustment elements may vary from that illustrated and described
herein. For example, while illustrated and described herein as
being spaced from the stud bolts that secure the end cover to the
pump casing, the adjustment elements may be located in proximity to
the stud bolts, but operate separately from the stud bolts in a
manner similarly described herein for effecting axial movement of
the end cover, and without the need for tools. Accordingly,
reference herein to particular details of the clean out assembly of
the present invention are by way of example, and not by way of
limitation.
* * * * *