U.S. patent application number 10/546694 was filed with the patent office on 2007-01-04 for pump.
Invention is credited to Daniel F. Brownson, Donald W. Racer.
Application Number | 20070003406 10/546694 |
Document ID | / |
Family ID | 32962556 |
Filed Date | 2007-01-04 |
United States Patent
Application |
20070003406 |
Kind Code |
A1 |
Racer; Donald W. ; et
al. |
January 4, 2007 |
Pump
Abstract
A pump, including a pump housing, defining an impeller chamber
in fluid communication with a pump inlet and pump outlet. An
impeller is rotatable within the impeller chamber and is attached
to an adaptor shaft. The adaptor shaft is rotatably held in an
intermediate housing that also serves as a mount for a drive
source, such as an electric drive motor. A bearing held within the
intermediate housing supports the adaptor shaft in both radial and
axial directions and includes socket structure directly engageable
with an output shaft of the drive motor. The socket structure
includes clamping sections that are urged into frictional
engagement with the output shaft of the drive source by a clamping
device. The socket structure may include one or more slots for
receiving a key carried by the drive shaft in order to provide a
positive mechanical coupling between the drive source and the drive
shaft. The shaft also includes tool engagement structure by which
the shaft can be immobilized during an impeller removal
procedure.
Inventors: |
Racer; Donald W.; (Shelby,
OH) ; Brownson; Daniel F.; (Manafield, OH) |
Correspondence
Address: |
John R. Hlavka;Watts Hoffmann Co.
PO Box 99839
Cleveland
OH
44199-0839
US
|
Family ID: |
32962556 |
Appl. No.: |
10/546694 |
Filed: |
February 27, 2004 |
PCT Filed: |
February 27, 2004 |
PCT NO: |
PCT/US04/06116 |
371 Date: |
August 31, 2006 |
Current U.S.
Class: |
415/111 |
Current CPC
Class: |
F04D 13/021 20130101;
F04D 29/20 20130101; F04D 29/049 20130101; F04D 9/007 20130101;
F04D 29/628 20130101 |
Class at
Publication: |
415/111 |
International
Class: |
F04D 29/08 20060101
F04D029/08 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 28, 2003 |
US |
60451072 |
Claims
1. A pump, comprising: a) a pump housing defining an impeller
chamber; b) an impeller rotatable within said chamber and operative
to pump fluid from a pump inlet to a pump outlet; c) an impeller
drive shaft to which said impeller is attached and defining an axis
of rotation for said impeller; d) a bearing rotatably supporting
said drive shaft in both radial and axial directions, said bearing
mounted within associated housing structure and held in said
associated housing structure by a locking member which inhibits
relative axial movement between said bearing and said associated
housing structure; and, e) a distal end of said drive shaft
including structure for engaging a rotatable output member of a
drive source, whereby rotation of said drive source produces
rotation in said impeller.
2. The pump of claim 1 further including a clamping device for
generating clamping forces between said distal end and said output
member.
3. The pump of claim 1 wherein said distal end defines a socket
structure for receiving an end of said drive source output
member.
4. The pump of claim 3 wherein said socket further defines a
plurality of clamping sections for frictionally engaging said end
of said output member.
5. The apparatus of claim 4 further including a clamping device for
urging said clamping sections inwardly in order to engage an outer
surface of said end of said output member.
6. The apparatus of claim 5 wherein said associated housing
structure is defined by a separable intermediate housing, said
intermediate housing mounting said drive source.
7. The pump of claim 6 wherein said intermediate housing defines an
oil bath chamber.
8. The pump of claim 7 further including a seal sealingly engaging
said impeller drive shaft and operative to inhibit fluid leakage
out of said oil bath chamber.
9. The pump of claim 1 wherein said drive shaft includes engagement
structure engageable by a maintenance tool whereby engagement of
said structure by said tool resists rotation of said shaft during
an impeller removal procedure.
10. A centrifugal pump, comprising: a) a pump housing defining an
impeller chamber in fluid communication with a pump inlet and a
pump outlet; b) an impeller rotatable within said impeller chamber
which upon rotation is operative to convey fluid from said pump
inlet to said pump outlet; c) said impeller attached to an adaptor
shaft and rotatable thereby; d) a seal having rotating and
non-rotating portions for inhibiting fluid leakage out of said
impeller chamber; e) said adaptor shaft rotatably supported by a
bearing carried in an intermediate housing that is attached to said
pump housing; f) said adaptor shaft defining a socket structure
adapted to receive a drive shaft forming part of a drive source for
the pump; g) said socket structure including clamping sections for
frictionally engaging said drive source drive shaft; and, h) a
clamping device for urging said clamping sections radially inwardly
in order to frictionally engage said drive shaft.
11. The pump of claim 6 wherein said an intermediate housing
provides a mounting surface for said drive source.
12. The pump of claim 11 wherein said intermediate housing provides
access openings by which said tool engaging structure on said shaft
can be engaged by a suitable tool.
13. The pump of claim 10 wherein said bearing is held within a
recess defined by said intermediate housing by a locking member and
is secured to said adaptor shaft by a pair of shaft locking members
which engage said shaft and which inhibit relative axial movement
between said shaft and said bearing.
14. The pump of claim 10 wherein said impeller is held to an
impeller end of said adaptor shaft by a threaded fastener.
15. The pump of claim 10 wherein said intermediate housing at least
partially defines an oil chamber which provides an oil bath for at
least portions of said impeller seal.
16. The pump of claim 9 wherein said engagement structure comprises
a pair of flats.
17. The pump of claim 9 wherein said engagement structure comprises
a recess.
18. The pump of claim 3 wherein said socket structure defines a
slot for receiving a key carried by said output member.
19. The centrifugal pump of claim 10 wherein said socket structure
defines a slot adapted to receive a key carried by said drive
source drive shaft, such that said drive shaft is mechanically
coupled to said adaptor shaft.
20. A pump, comprising: a) a pump housing defining an impeller
chamber; b) an impeller rotatable within said impeller chamber; c)
an intermediate housing having one portion attached to said pump
housing and another portion mounting a drive source for producing
rotation in said impeller; d) an impeller drive shaft rotatably
carried by said intermediate housing and operatively connected to
said impeller, such that rotation of said drive shaft produces
rotation in said impeller; e) a bearing rotatably supporting said
adaptor shaft and mounted within said intermediate housing; and, f)
said drive shaft defining drive source coupling structure at an end
that is opposite the end to which said impeller is mounted, said
coupling structure at least frictionally engaging an output member
of said drive source.
21. The pump of claim 20 wherein said coupling structure includes
means for providing a keyed coupling between said drive shaft and
said drive source.
Description
TECHNICAL FIELD
[0001] The present invention relates generally to fluid pumps and,
in particular, to a method and apparatus for facilitating the
connection between an impeller and impeller drive source in a
centrifugal pump.
BACKGROUND ART
[0002] Centrifugal pumps are well known in the art and are used for
many fluid pumping applications. For example, centrifugal pumps
have been used to pump water from one water station to another.
They may also be used in construction applications, i.e., to pump
water from an excavation site. An example of the type of pump to
which this invention pertains can be found in U.S. Pat. No.
3,898,014, which is hereby incorporated by reference.
[0003] Customers for this type of pump, may desire various types of
driver sources for driving the pumping portion, i.e., impeller, of
the pump. For example, customers may request electric motors of
various horse powers, internal combustion engines or fluid pressure
operated motors, both pneumatic and hydraulic. In the past, the
adaptation or connection of various drive sources to the impeller
has, in some cases, been difficult and not cost effective. In other
cases the connection between the drive motor and pump has been a
source of unreliability.
DISCLOSURE OF INVENTION
[0004] The present invention provides a new and improved pump
construction which enables a variety of drive sources, such as
electric motors, internal combustion engines and fluid pressure
operated motors to be connected to the rotating components of a
pump.
[0005] In the illustrated embodiment, an impeller forming part of a
centrifugal pump is secured to an adaptor shaft. The adaptor shaft
is rotatably supported within an intermediate housing by a bearing
held within the housing and also locked to the adaptor shaft. The
bearing supports both radial and axial loads during pump operation.
The adaptor shaft has an outboard end adapted to engage the output
shaft of the drive source. A clamping device, such as a split
collar locks the adaptor shaft to the motor shaft. The adaptor
shaft also includes structure engageable by a tool which prevents
rotation of the shaft so as to facilitate removal of the
impeller.
[0006] Additional features of the invention and a fuller
understanding will be obtained by reading the following detailed
description made in connection with the accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
[0007] FIG. 1 is a sectional view of a centrifugal pump assembly
including a drive motor for rotating an impeller located within the
pump;
[0008] FIG. 2 is a sectional view of an intermediate housing
forming part of the pump assembly shown in FIG. 1;
[0009] FIG. 2A is an enlarged, fragmentary view of a seal forming
part of the intermediate housing;
[0010] FIG. 2B is an end view of the intermediate housing;
[0011] FIG. 3 is a sectional view of the intermediate housing with
internal components removed;
[0012] FIG. 3A is an enlarged, fragmentary view of a bearing
receiving recess forming part of the intermediate housing;
[0013] FIG. 3B is an elevational view of the intermediate housing
shown in FIG. 3;
[0014] FIG. 4 is a side view, partially in section, of an adaptor
shaft forming part of the present invention;
[0015] FIG. 4A is a fragmentary, elevational view of an outboard
end of the adaptor shaft shown in FIG. 4;
[0016] FIG. 5 is a schematic representation showing components made
according to the present invention that are used to couple an
output shaft of a drive motor with an impeller; and,
[0017] FIG. 6 is a fragmentary cut-away view showing an alternate
construction of the adaptor shaft.
BEST MODE FOR CARRYING OUT THE INVENTION
[0018] FIG. 1 illustrates the overall construction of a centrifugal
pump that incorporates the present invention. For purposes of
explanation, the invention will be described in connection with a
self-priming pump. The illustrated pump is of the type disclosed in
U.S. Pat. No. 3,898,014 which is owned by the present assignee. A
detailed explanation of the operation of a self-priming pump can be
obtained by reference to U.S. Pat. No. 3,898,014.
[0019] It should be noted that the present invention can also be
adapted to other types of centrifugal pumps and should not be
limited to the self-priming pump construction illustrated.
[0020] By way of background, the illustrated self-priming pump
includes an inlet or section port 10 to which fluid to be pumped is
drawn and an outlet or discharge port 14 by which pumpage leaves
the pump. A rotatable impeller 20 located in a volute chamber 20a
draws fluid though the suction port 10 and conveys it under
pressure to the discharge port 14. A check valve 22 located at the
suction port 10 closes upon pump shutdown and captures fluid within
the pump. The check valve 22 facilitates start up of the pump after
shutdown and reduces or eliminates the need for priming the pump.
As more fully explained in U.S. Pat. No. 3,898,014, the disclosed
pump has self priming capability, even in circumstances when the
check valve fails to fully close. Again, this self priming
capability is fully disclosed in U.S. Pat. No. 3,898,014.
[0021] The impeller 20 forms part of a removable rotating assembly
indicated generally by the reference character 30. The rotating
assembly 30 includes an intermediate housing 32 which includes a
pair of flanges 32a, 32b. The flange 32a is intended to mate with a
flange surface defined by a pump housing 34. A plurality of bolts
35 are used to secure the flange 32a to the pump housing 34.
[0022] The flange 32b defined by the intermediate housing 32
provides a mounting surface for an impeller driver, such as an
electric drive motor 36 shown in FIG. 1. The drive motor 36 can be
replaced by other types of drive devices, such as an internal
combustion engine or a fluid pressure operated motor.
[0023] According to the invention, the drive motor 36 is
operatively coupled to the impeller by components (to be described)
that are contained within the intermediate housing 32.
[0024] In prior art constructions, the shaft, to which the impeller
20 is mounted, is coupled to an output shaft of the drive motor by
a coupling device which may permit some misalignment between the
impeller shaft and the motor drive shaft. These couplers can be
expensive and can be a source of wear and require periodic
maintenance. The present invention addresses and eliminates the
problem associated with motor-to-impeller shaft couplers by
limiting the need for a separate coupler and by providing
independent support for the shaft to which the impeller 20 is
directly attached.
[0025] In an alternate prior art construction, special drive motors
were used each having an elongate shaft to which the impeller 20
was directly mounted. In these latter constructions, the
positioning of the impeller within the volute chamber, at least in
some instances, was a function of the motor manufacturer. In these
types of prior art constructions radial and axial loads exerted by
the impeller 20 were transmitted directly to the motor.
Misalignment or improper dimensioning of the drive source could
result in improper clearance between the impeller 20 and its
associated wear plate 90 (see FIG. 1). The present invention also
obviates these problems associated with the prior art
construction.
[0026] Referring also to FIG. 2, the impeller 20 is secured to the
end of an adaptor shaft 40 by a bolt 42. Alternately, the impeller
may be screwed directly onto a threaded section (not shown) of the
shaft 40. Referring also to FIG. 2A, a seal assembly 44 inhibits
leakage of pumpage out of the volute chamber 20a. The seal 44 may
be a face-type seal including non-rotating and rotating portions,
an example of which is disclosed in U.S. Pat. Nos. 3,447,810 and
4,815,747 which are both incorporated by reference.
[0027] To provide improved seal life and dry running capability,
the intermediate housing 32 defines an oil chamber 48 which keeps
at least portions of the seal 44 immersed in oil, thus improving
its life. The adaptor shaft 40 is rotatably supported and located
both radially and axially within the intermediate housing 32 by a
bearing 50, preferably a sealed ball bearing. The ball bearing 50
is secured to the adaptor shaft 40 by a pair of lock rings 52
disposed on either side of the bearing 50 and held in associated
lock ring grooves 52a formed on the adaptor shaft 40.
[0028] Referring also to FIGS. 3 and 3A, the bearing 50 is further
positioned in a bearing recess 54 defined in a bearing housing
portion 55 that forms part of the intermediate housing 32 and
secured there by a lock ring 56 held in a groove 56a. The bearing
50 supports both radial and axial loads during operation of the
pump and reduces or eliminates radial and axial thrust forces from
being transmitted to the drive motor 36, thus improving drive motor
life. A seal 60 is held in the bearing support housing portion 55
and sealingly engages the adaptor shaft 40. The seal inhibits oil
leakage out of the oil bath chamber 48.
[0029] Referring to FIGS. 4 and 4A, an outboard end 40b of the
adaptor shaft 40 defines a socket like structure 70 adapted to
receive the end of a shaft 36a of the drive source 36. In the
illustrated embodiment, the socket 70 includes a plurality of slits
or notches 72. In the illustrated embodiment, the outboard end 40b
of the adaptor shaft 40 includes four slits thus dividing the
socket 70 into four clamping sections 70a. To connect the outboard
end 40b of the adaptor shaft 40 to the shaft 36a of the drive motor
36, the end of the drive motor shaft 36 is inserted into the socket
end 70 of the adaptor shaft 40. A conventional split locking collar
76 is then positioned over the segments 70a and then tightened as
by a socket head screw or screws 78. By tightening the split collar
76, the individual segments 70a are urged radially inwardly in
order to clamp the outside of the drive motor shaft 36a, thus
rigidly locking the drive motor shaft 36 to the adaptor shaft 40.
The coupling of the motor shaft 36a to the impeller 20 using the
above described components is shown in FIG. 5 with the intermediate
housing 32 removed.
[0030] According to a feature of the invention, in order to
facilitate maintenance on the impeller 20, the adaptor shaft
includes multiple flats or other structure engageable by a tool. In
the illustrated embodiment, a pair of flats 80 is formed, as by
milling, onto the shaft 40. The flats 80 are positioned 180.degree.
apart and are adapted to be engaged by an appropriately sized open
end wrench or other similar tool. The tool can be used to prevent
rotation of the adaptor shaft 40 as the impeller securing bolt or
nut 42 is removed (or to allow the impeller to be unscrewed from
the shaft in those constructions that use a threaded shaft).
Removal of the fastener 42 allows removal of the impeller 20 for
replacement or to gain access to the seal assembly 44. Access to
the flats 80 (and the collar 76) is provided by a pair of openings
84 formed in the intermediate housing 32.
[0031] The invention contemplates alternate constructions for
providing the means to prevent rotation of the adaptor shaft 40.
For example, the shaft itself may be hex-shaped or include a
hex-shaped portion which could be engaged by a suitable tool. The
shaft 40 may also be formed with three or more flats to facilitate
engagement by a suitable tool.
[0032] FIG. 6 illustrates an alternate construction for the distal
end of the adaptor shaft 40 which is capable of transmitting higher
torques than the socket structure 70 shown in FIG. 4. In this
alternate embodiment, an adaptor shaft 40' includes a socket
structure 70' that provides a positive locking between the socket
70' and an output end 36a' of a drive motor 36'. In this
embodiment, the output shaft 36a' of the drive motor 36 includes a
keyway 100. A key 102 carried in the keyway 100 is engageable by an
associated slot 72 (shown in FIG. 4) defined between adjacent
clamping sections 70a'. In this alternate embodiment, the coupling
between the adaptor shaft 40' and the drive shaft 36a' does not
rely solely on a friction engagement. The illustrated key
arrangement mechanically couples the drive shaft 36a' to the
adaptor shaft 40'.
[0033] The adaptor shaft 40' shown in FIG. 6, also includes an
alternate structure for immobilizing the shaft when the impeller 20
is to be removed. The embodiment shown in FIGS. 1-5 utilizes flats
80 which were engageable by a suitable tool. Referring to FIG. 6,
the alternate adaptor shaft 40' includes a recess 80' that is
engageable by a suitable pin-like tool 110 via an access hole 112
defined in the intermediate housing 32'. As seen in FIG. 6, a
suitable tool may comprise a socket tool extension bar.
[0034] In the preferred construction of the present invention, the
clearance between the impeller 20 and the wearplate 90 can be
adjusted by shims 94 (see FIG. 1) placed between the pump housing
34 and the inner flange 32a of the intermediate housing 32. Because
the adaptor shaft 40 (to which the impeller 20 is secured) is
located both radially and axially within the intermediate housing
32 by the bearing 50, dimensional variations in the motor shaft 36a
or the motor mounting do not affect the impeller-to-wearplate
clearance.
[0035] As should be apparent, the present invention facilitates the
adaptation of various drive sources to the rotating components of
the pump. The use of the bearing 50 to rotatably support and locate
the adaptor shaft 40 (to which the impeller is attached)
substantially reduces the possible interaction between the
construction/mounting of the drive source and the position of the
impeller within the pump. The present invention also eliminates the
need for separate, sometimes expensive couplers to couple a drive
motor to an impeller as used in some prior art constructions.
[0036] Although the invention has been described with a certain
degree of particularity, it should be understood that those skilled
in the art can make various changes to it without departing from
the spirit or scope of the invention as hereinafter claimed.
* * * * *