U.S. patent application number 10/997667 was filed with the patent office on 2005-06-30 for rodder pump.
This patent application is currently assigned to Elgin Sweeper. Invention is credited to Padgett, John D., Strauser, Daniel P..
Application Number | 20050142012 10/997667 |
Document ID | / |
Family ID | 34465395 |
Filed Date | 2005-06-30 |
United States Patent
Application |
20050142012 |
Kind Code |
A1 |
Padgett, John D. ; et
al. |
June 30, 2005 |
Rodder pump
Abstract
A closed loop rodder pump is disclosed which can include a tube
assembly and a reciprocating cylinder assembly disposed therein.
The cylinder assembly can include a piston portion and a plunger.
The piston portion can sealingly engage the tube assembly. In some
embodiments, the cylinder assembly can include a second plunger to
provide the pump with a dual-acting feature. The rodder pump can be
used in a water jetter cleaning system of a vehicle for cleaning
catch basins and/or sewers.
Inventors: |
Padgett, John D.; (South
Elgin, IL) ; Strauser, Daniel P.; (Elgin,
IL) |
Correspondence
Address: |
LEYDIG VOIT & MAYER, LTD
TWO PRUDENTIAL PLAZA, SUITE 4900
180 NORTH STETSON AVENUE
CHICAGO
IL
60601-6780
US
|
Assignee: |
Elgin Sweeper
Elgin
IL
|
Family ID: |
34465395 |
Appl. No.: |
10/997667 |
Filed: |
November 24, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60525349 |
Nov 26, 2003 |
|
|
|
Current U.S.
Class: |
417/437 ;
417/460 |
Current CPC
Class: |
F04B 9/113 20130101;
F04B 9/1172 20130101; F04B 9/105 20130101; F04B 53/109
20130101 |
Class at
Publication: |
417/437 ;
417/460 |
International
Class: |
F04B 001/00; F04B
019/02 |
Claims
What is claimed is:
1. A rodder pump comprising: a first tube defining a first pressure
chamber; a second tube defining a hydraulic chamber, the second
tube connected to the first tube; a gland interposed between the
first pressure chamber and the hydraulic chamber; and a cylinder
assembly including a piston part and a first plunger, the cylinder
assembly reciprocally movable within the first and second tubes;
wherein the piston portion is in sealing contact with the hydraulic
chamber and the first plunger is in sealing contact with the gland,
the first plunger movable such that the first plunger can extend
into the first pressure chamber.
2. The rodder pump according to claim 1, wherein the second tube
includes a first hydraulic port and a second hydraulic port, the
first and second hydraulic ports being in fluid communication with
the hydraulic chamber, the piston portion being reciprocally
movable within the hydraulic chamber, the cylinder assembly being
movable in response to a flow of hydraulic fluid through at least
one of the first and second hydraulic ports.
3. The rodder pump according to claim 2, further comprising: first
and second sensors disposed adjacent first and second ends of the
hydraulic chamber, the sensors configured to detect when the piston
portion is proximal thereto.
4. The rodder pump according to claim 3, wherein the second tube
includes a first and a second sensor port, the sensors respectively
disposed in the first and second sensor ports.
5. The rodder pump according to claim 3, further comprising: a butt
fitting disposed at a distal end of the first tube, the butt
fitting having a fluid port in fluid communication with the first
pressure chamber.
6. The rodder pump according to claim 5, wherein the fluid port of
the butt fitting has a valve disposed therein, the valve being
configured to selectively control the flow of fluid through the
fluid port in at least one direction.
7. The rodder pump according to claim 6, wherein the valve
comprises an integrated dual check valve.
8. The rodder pump according to claim 2, wherein a first fluid port
and a second fluid port are in fluid communication with the
pressure chamber.
9. The rodder pump according to claim 2, further comprising: a
third tube defining a second pressure chamber, the third tube
connected to the second tube, the second tube disposed between the
first and second tubes; a second gland disposed between the
hydraulic chamber and the second pressure chamber; wherein the
cylinder assembly includes a second plunger, the second plunger
being in opposing relationship to the first plunger such that the
piston part is disposed between the first and second plungers, the
cylinder assembly reciprocally movable within the first, second,
and third tubes, the second plunger being in sealing contact with
the second gland, the second plunger movable such that the second
plunger can extend into the second pressure chamber.
10. The rodder pump according to claim 9, further comprising: first
and second sensors disposed adjacent first and second ends of the
hydraulic chamber, the sensors configured to detect when the piston
portion is proximal thereto.
11. The rodder pump according to claim 10, further comprising: a
first butt fitting disposed at a distal end of the first tube, the
first butt fitting having a fluid port in fluid communication with
the first pressure chamber; a second butt fitting disposed at a
distal end of the third tube, the second butt fitting having a
fluid port in fluid communication with the second pressure
chamber.
12. The rodder pump according to claim 11, wherein the fluid port
of the first butt fitting has a first valve disposed therein, the
first valve being configured to selectively control the flow of
fluid through the fluid port in at least one direction.
13. The rodder pump according to claim 12, wherein the first valve
comprises an integrated dual check valve.
14. The rodder pump according to claim 11, wherein a common feed
line connects the fluid port of the first butt fitting and the
fluid port of the second butt fitting.
15. A rodder pump comprising: a first tube defining a first
pressure chamber; a second tube defining a hydraulic chamber, the
second tube sealingly connected to the first tube, the second tube
having first and second hydraulic port respectively disposed
adjacent first and second ends thereof, the first and second
hydraulic ports being in fluid communication with the hydraulic
chamber; a third tube defining a second pressure chamber, the third
tube sealingly connected to the second tube, the second tube
disposed between the first and second tubes; a cylinder assembly
including a piston part, a first plunger, and a second plunger, the
cylinder assembly reciprocally movable within the first, second and
third tubes such that the first plunger is reciprocally movable
within the first pressure chamber, the piston part is reciprocally
movable within the hydraulic chamber, and the second plunger is
reciprocally movable within the second pressure chamber; wherein
the cylinder assembly is selectively movable in response to a flow
of hydraulic fluid through the first hydraulic port to move the
cylinder in a first direction wherein the first plunger moves in a
direction from the first pressure chamber toward the hydraulic
chamber and through the second hydraulic port to move the cylinder
in a second direction wherein the second plunger moves in a
direction from the second pressure chamber toward the hydraulic
chamber, the second direction opposing the first direction.
16. A vehicle for cleaning a pipe comprising: a reel; a length of
hose that is woundable upon the reel; a water tank for storing a
supply of water; a water pump in fluid communication with the water
tank; a rodder pump, the rodder pump being in fluid communication
with the water pump to receive water from the water tank, the
rodder pump being in fluid communication with the hose to deliver
supply of pressurized water thereto; a hydraulic supply in
hydraulic communication with the rodder pump to selectively operate
the rodder pump; wherein the rodder pump comprises: a first tube
defining a first pressure chamber, the first pressure chamber being
in fluid communication with the hose and with the water tank; a
second tube defining a hydraulic chamber, the second tube sealingly
connected to the first tube, the hydraulic chamber being in
hydraulic communication with the hydraulic supply; a cylinder
assembly including a piston part and a first plunger, the cylinder
assembly reciprocally movable within the first and second tubes in
response to the flow of the hydraulic fluid in the hydraulic
chamber such that the first plunger is reciprocally movable over a
suction stroke and a discharge stroke; wherein water can flow into
the first pressure chamber from the water tank during the suction
stroke and water can be discharged from the first pressure chamber
to the length of hose during the discharge stroke.
17. The vehicle according to claim 16, further comprising: a
collection body; a vacuum hose connected to the collection body;
and a vacuum source operably connected to the vacuum hose line such
that a vacuum is selectively generated in the vacuum hose to suck
debris through the vacuum hose and store in the collection
body.
18. The vehicle according to claim 17, further comprising: a
multi-stage blower filtration system disposed between the vacuum
source and the vacuum hose.
19. The vehicle according to claim 18, wherein the multi-stage
blower filtration system includes a centrifugal cyclone and a
stainless steel screen strainer for filtering debris from the
vacuum source.
20. The vehicle according to claim 17, further comprising: a boom
mounted on the vehicle, the vacuum hose being supported by the
boom.
21. The vehicle according to claim 20, wherein the boom is
extendable over a predetermined range.
22. The vehicle according to claim 20, wherein the second tube of
the rodder pump includes a first hydraulic port and a second
hydraulic port, the first and second hydraulic ports being in fluid
communication with the hydraulic chamber and with the hydraulic
supply, the piston portion being reciprocally movable within the
hydraulic chamber, the cylinder assembly being selectively movable
in response to the flow of hydraulic fluid through the first
hydraulic port to move the cylinder in a first direction and
through the second hydraulic port to move the cylinder in a second
direction, the second direction opposing the first direction.
23. The vehicle according to claim 22, wherein the rodder pump
further comprises a third tube defining a second pressure chamber,
the third tube sealingly connected to the second tube, and the
cylinder assembly includes a second plunger, the second plunger
movable such that the second plunger can extend into the second
pressure chamber, the second pressure chamber being in fluid
communication with the water tank and the length of hose, the
second plunger being reciprocally movable over a suction stroke and
a discharge stroke, the second plunger arranged with the second
pressure chamber such that water can flow into the second pressure
chamber from the water tank during the suction stroke of the second
plunger and water can be discharged from the second pressure
chamber to the length of hose during the discharge stroke of the
second plunger.
24. The vehicle according to claim 23, wherein the suction stroke
and the discharge stroke of the first plunger are in alternating
relationship to the suction stroke and the discharge stroke of the
second plunger such that when the first plunger is undergoing the
suction stroke, the second plunger is undergoing the discharge
stroke.
25. The vehicle according to claim 24, wherein the first pressure
chamber and the second pressure chamber are in fluid communication
with each other via a common feed line such that water is
alternatingly discharged from the first and second pressure
chambers into the common feed line during the respective discharge
strokes of the first and second plungers, the common feed line
being in fluid communication with the length of hose.
Description
CROSS-REFERENCE TO RELATED PATENT APPLICATION
[0001] This application claims the benefit of U.S. Provisional
Patent Application No. 60/525,349, filed Nov. 26, 2003, the entire
disclosure of which is incorporated herein by reference in its
entirety.
FIELD OF THE INVENTION
[0002] This invention relates in general to a reciprocating pump
driven by pressurized fluid from a hydraulic pump and more
particularly to a closed-loop, hydraulically-driven rodder
pump.
BACKGROUND OF THE INVENTION
[0003] Heretofore vacuum cleaning of catch basins and flushing of
sewer pipes has required the use of at least two separate vehicles.
A first vehicle with a hose reel mounted on the rear end thereof
was positioned at the manhole and a high pressure hose fitted with
a jet nozzle was introduced into the sewer. Water from a tank on
the vehicle was pumped through the hose at pressures at about 1,000
pounds per square inch to drive the hose through the pipe against
the water flow. Pressure drops along the hose length were
considerable and at 400 feet, available pressures were only about
600 to 800 pounds per square inch. Debris flushed from the sewer
pipe was then sucked out of the catch basin by a second follow-up
vehicle. This multiple vehicle system duplicated personnel and the
rear mounted hose reel exposed the personnel to traffic
hazards.
[0004] A single vehicle for vacuum cleaning of catch basins and
flushing of sewer pipes with water surged through a hose and nozzle
at pressures of about 2,000-3,000 pounds per square inch is known,
an example being disclosed and described in U.S. Pat. No.
3,658,589, entitled, "Catch Basin And Sewer Pipe Cleaner." Such a
vehicle is typically provided with a pump to deliver water at
operating pressure for cleaning the catch basins and sewer pipes.
An engine-driven oil pump, located either on the vehicle or
remotely therefrom, can hydraulically drive the pump.
SUMMARY OF THE INVENTION
[0005] The invention provides a closed-loop, hydraulically-driven
rodder pump. The pump of the present invention seeks to improve
upon the piston pump shown and described in U.S. Pat. No.
3,700,360, entitled, "Double-Acting Tandem Piston Pump," which is
incorporated herein by this reference in its entirety.
[0006] The present invention can be used in a vehicle for cleaning
sewer pipes and catch basins by the use of water pressure and the
carrying power of moving air. In one embodiment, a combined catch
basin and sewer pipe cleaning vehicle includes a large debris
collecting dump body from which air is continuously pulled by an
engine driven fan on the vehicle and easily opened for dumping. The
vehicle also has a separate water tank, a reciprocating water pump
driven by pressurized oil from a vehicle engine-driven hydraulic
pump, and a reeled high pressure hose with a self-propelling jet
nozzle receiving surges of high pressure water from the water pump,
which can be in the form of a closed-loop, hydraulically-driven
rodder pump. In other embodiments, the rodder pump of the present
invention can be used in other vehicles, such as, hydroexcavaters,
for example.
[0007] In one aspect of the invention, a pair of single cylinder
reciprocating rodder pumps can be provided in a closed loop system.
In yet another embodiment, a single rodder pump having a
dual-acting cylinder assembly can be provided in a closed loop
system.
[0008] These and other features of the present invention will
become apparent to one of ordinary skill in the art upon reading
the detailed description, in conjunction with the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a perspective view of an embodiment of a pump
according to the present invention.
[0010] FIG. 2 is a front elevational view of the pump of FIG.
1.
[0011] FIG. 3 is an enlarged detailed view taken from FIG. 2 of the
pump of FIG. 1.
[0012] FIG. 4 is an enlarged detailed view taken from FIG. 2 of the
pump of FIG. 1.
[0013] FIG. 5 is an enlarged detailed view taken from FIG. 2 of the
pump of FIG. 1.
[0014] FIG. 6 is a first end view of the pump of FIG. 1.
[0015] FIG. 7 is a second end view of the pump of FIG. 1.
[0016] FIG. 8 is a diagrammatic view of an input circuit for a pair
of pumps as shown in FIG. 1, which is configured as a deintensifier
circuit.
[0017] FIG. 9 is a perspective view of another embodiment of a pump
according to the present invention.
[0018] FIG. 10 is a perspective view of a cylinder assembly of the
pump of FIG. 9.
[0019] FIG. 11 is a front side elevational view, partially in
section, of the pump of FIG. 9.
[0020] FIG. 12 is a fragmentary top view of the pump of FIG. 9.
[0021] FIG. 13 is an enlarged detailed view taken from FIG. 11 of
the pump of FIG. 9.
[0022] FIG. 14 is a bottom view, partially in section, of the pump
of FIG. 9.
[0023] FIG. 15 is an enlarged detailed view taken from FIG. 14 of
the pump of FIG. 9.
[0024] FIG. 16 is an end view of the pump of FIG. 9.
[0025] FIG. 17 is a cross-sectional view taken along line 17-17 in
FIG. 11 of the pump of FIG. 9.
[0026] FIG. 18 is a cross-sectional view taken along line 18-18 in
FIG. 14 of the pump of FIG. 9.
[0027] FIG. 19 is a cross-sectional view taken along line 19-19 in
FIG. 14 of the pump of FIG. 9.
[0028] FIG. 20 is a cross-sectional view taken along line 20-20 in
FIG. 14 of the pump of FIG. 9.
[0029] FIG. 21 is a cross-sectional view of a check valve suitable
for use with the pump of the present invention.
[0030] FIG. 22 is a diagrammatic view of an input circuit which
includes the pump of FIG. 9.
[0031] FIG. 23 is a side elevational view of a vehicle for cleaning
sewer pipes and catch basins that includes a pump according to the
present invention.
[0032] FIG. 24 is a somewhat schematic perspective view, partially
in section, of another embodiment of a rodder pump according to the
present invention having a dual-acting cylinder.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0033] Referring to FIGS. 1-7, an embodiment of a pump 50 according
to the present invention is shown that includes a single acting
cylinder 52 (see FIG. 2). Referring to FIG. 1, the pump 50 includes
first and second tube assemblies 54, 56. The first tube assembly 54
has a butt fitting 58 mounted thereto at a first end 59 thereof.
The butt fitting 58 can include a first hydraulic port 60. Disposed
at the other end 61 of the first tube assembly 54 is a gland
assembly 62. The second tube assembly 56 can have a pair of flanges
64, 65 disposed at the respective ends thereof. The first and
second tube assemblies 54, 56 can be mounted together by a tie rod
assembly 68, which can comprise a plurality of tie rods 69
extending through the butt fitting 58, the gland assembly 62, and
the first flange 64 of the second tube assembly 56 and a plurality
of bolts 70 threadedly engaged with the tie rods 69 to retain the
first and second tube assemblies 54, 56 in substantially fixed
relationship relative to each other.
[0034] The first tube assembly 54 can include a second hydraulic
port 78 disposed adjacent the second end 61 thereof and a pair of
sensor ports 82, 83 disposed respectively adjacent the first and
second ends 59, 61 of the first tube assembly 54. The sensor ports
82, 83 can each be sized to respectively accommodate a sensor
configured to detect the presence of the cylinder when it is in
proximity thereto. The first hydraulic port 60 can be configured as
a No. 16 SAE port, for example, and the second hydraulic port 78
can be configured as a No. 8 SAE port, for example. The second tube
assembly 56 can include a fluid port 86 in the second flange 65
disposed in axial alignment with the tube portion thereof.
[0035] Referring to FIG. 2, the cylinder assembly 52 is disposed
within the first tube assembly 54 and is reciprocally movable over
a discharge stroke, when moving in a discharge direction 88, and
over a suction stroke, when moving in a charge direction 89. The
cylinder assembly 52 can include a plunger 90 having a large
diameter section 92 and a small diameter section 94, a piston
portion 96 mounted to the plunger 90 via a lock nut 98 which is
threadedly engaged with the small diameter section 94 of the
plunger 90. The cylinder assembly 52 is shown in FIG. 2 in a
discharge or power position wherein the cylinder assembly is ready
to discharge fluid from the fluid port 86 through a pressure
stroke. The piston portion 96 is in sealing contact with an
interior surface 99 of the first tube 54. The plunger 90 extends
through an opening 100 defined by the gland 62 and the first flange
64 such that at least a portion of the plunger 92 is disposed
within the second tube assembly 56. The plunger 90 is in sealing
contact with the gland 62.
[0036] Referring to FIG. 3, the first port 60 is in fluid
communication with the interior of the first tube assembly 54. The
butt fitting 58 can include a circumferential groove 104 which can
receive a back-up washer 106 and an O-ring seal 108 to provide a
sealed connection between the butt fitting 58 and the first
tube.
[0037] Referring to FIG. 4, the first sensor port 82 can be
configured to receive a suitable sensor therein, such as a Hall
effect sensor, for detecting the position of the cylinder assembly.
The sensor port 82 can include a back-up washer 110 and an O-ring
seal 112 therein for sealingly engaging the sensor 109 inserted
therein. The sensor can detect when the piston portion 96 is
proximate the first sensor port and send a control signal to a
controller to operate various valves in response to the position of
the cylinder assembly. The sensor can be electrically connected to
the controller via an electrical wire, for example. When the piston
portion 96 is proximate the first sensor port 82, the cylinder
assembly is in a discharge position and is ready to undergo the
pressure stroke. In some embodiments, the sensor can be a magnetic
field sensor, such as one commercially available from Balluf Inc.
of Florence, Ky., including one of the sensors designated under the
series BMF 32M, including, for example, the sensor referenced with
part number BMF-32M-PS-C-2-S49, for example.
[0038] Referring to FIG. 2, the second sensor port 83 can sealingly
house a similar sensor. The second sensor port 83 is disposed such
that it can detect when the cylinder assembly is in a charge
position and is ready to undergo the suction stroke by moving in
the charge direction 89.
[0039] Referring to FIG. 4, the piston assembly 96 can include a
wear ring 118 and a seal 120 made from any suitable material, such
as, any suitable fluoropolymer resin sold under the Teflon.RTM.
brand by E. I. duPont de Nemours and Company, for example. The wear
ring 118 and the seal 120 are disposed circumferentially around the
piston 96 in a pair of grooves 122, 124, respectively. An O-ring
126 can be provided that is in sealing engagement with the piston
assembly 96 and the small diameter section 94 of the plunger 90, as
shown in FIG. 2.
[0040] Referring to FIG. 5, the gland assembly 62 can include a
breather 130 which communicates with the interior of the first tube
assembly 54. The gland assembly 62 can include a back-up washer 132
and an O-ring seal 134 disposed in a circumferential groove 136. A
Z-seal 140 can extend around the breather 130 and be in contacting
relationship with the plunger 90. A wiper 142 can extend from the
gland assembly such that it is in contacting relationship with the
plunger 90. An O-ring seal 146 can be disposed between the gland
assembly 62 and the first flange 64 of the second tube
assembly.
[0041] Referring to FIG. 6, the butt fitting 58 is shown. Referring
to FIG. 7, the second flange 65 of the second tube assembly is
shown. The fluid port 86 can have a chamfered perimeter 148. The
second flange 65 can include a plurality of mounting bores 149.
[0042] Referring to FIG. 2, to move the cylinder assembly 52 in the
discharge direction 88, hydraulic fluid can be conveyed through the
first hydraulic port 60 such that it acts upon the piston portion
96 of the cylinder 52, thereby driving the large diameter section
92 of the plunger 90 into the second tube assembly 56. Once the
piston assembly 96 is disposed adjacent the second sensor port 83,
the sensor disposed therein can detect the presence of the piston
assembly and, in turn, signal the controller to cease the flow of
hydraulic fluid through the first hydraulic port 60 and to initiate
the flow of hydraulic fluid through the second hydraulic port 78.
The hydraulic fluid flowing through the second hydraulic port 78
can act upon the piston assembly 96 of the cylinder assembly 52,
thereby driving the cylinder assembly 52 in the charged direction
to move the cylinder assembly through the section stroke. Once the
piston assembly 96 is adjacent the first sensor port 82, the sensor
disposed therein can signal the controller to cease the flow of
hydraulic fluid through the second hydraulic port 78 and to
initiate the flow of hydraulic fluid through the first hydraulic
port 60, thereby sending the cylinder 52 in the discharge direction
to travel over the pressure stroke yet again. The pump 50 can
continue to operate in this sequence, reciprocating between the
pressure stroke and the suction stroke.
[0043] Any suitable valving can be used to allow fluid, such as
water, for example, to selectively enter the second tube assembly
56 via the fluid port 86 where the plunger can act upon the fluid
during the pressure stroke so that pressurized fluid can exit the
fluid port 86. In some embodiments, the second tube assembly can
include a pair of fluid ports, with one port for receiving fluid
therethrough for delivering fluid to the pump to be acted upon by
the cylinder assembly, and the other port for discharging
pressurized fluid from the pump. The fluid entering the second tube
assembly can be pressurized to an initial level by any suitable
pump before the cylinder assembly acts upon it.
[0044] Referring to FIG. 8, an embodiment of a closed loop pump
circuit 170 is shown. The pump circuit 170 is configured to have a
1:1 ratio between input and output. The pump circuit 170 can
include a pair of pumps 50, 51 that are both similar to the pump
shown in FIG. 1. The pumps 50, 51 can be fluidly connected to each
other via a connecting line 172 connecting the first hydraulic
ports 60 to each other. The pump circuit 170 can also include a
valve package 180 and a pump and tank assembly 182.
[0045] The valve package 180 can be connected to the second
hydraulic ports 78 of the pumps 50, 51 by first and second drive
lines A, B, respectively. The valve package 180 can be operated to
selectively deliver hydraulic fluid to the pumps 50, 51 based upon
the valve condition of the valve package. The valve package 180 and
the sensors disposed in the first and second pumps 50, 51 can be
electrically connected to a controller to allow the valve package
to change its valve condition in response to the position of the
cylinders 52 within the pumps 50, 51, which positions can be
communicated to the controller by the sensors. The valve package
180 can be operated to selectively drive the pumps 50, 51 such that
the pumps operate in tandem with the cylinder assemblies 52
operating in alternating sequence. The first pump 50 can be moving
through a pressure stroke while the second pump is undergoing a
suction stroke and vice versa. The sensors can communicate with the
valve package 180 via the controller to yield the desired
operation.
[0046] The valve package 180 can include a directional valve 184 to
direct the hydraulic fluid through one of the drive lines A, B, a
pilot valve 186 connected to the directional valve 184 and to the
controller, a relief valve 188, and first and second control valves
190, 191 and check valves 192, 193 interposed between the pilot
valve 186 and the directional valve 184. The pilot valve 186 is
provided to operate the directional valve 184 based upon the
signals the pilot valve 186 receives from the controller. The pilot
valve 186 can operate to selectively change the condition of the
directional valve 184 to produce the desired operation of the pumps
50, 51.
[0047] The pump and tank assembly 182 can include a pump 196 and a
tank 198 and can include a plurality of filters.
[0048] In operation, hydraulic fluid can be delivered through the
second drive line B to the second hydraulic port 78 of the second
pump 51 whose cylinder assembly 52 moves in response thereto in the
charge direction 89. The cylinder forces hydraulic fluid in the
second pump 51 out of the first port 60 thereof through the line
172 and into the first port 60 of the first pump 50. The hydraulic
fluid entering the first pump 50 acts upon the cylinder assembly 52
therein, moving the cylinder 52 in the discharge direction 88. The
cylinder assembly 52 of the first pump 50 can act upon fluid
disposed in the second tube assembly thereof to drive the fluid out
of the first pump 50 in a pressurized condition. When the cylinder
assembly 52 of the first pump 50 reaches the end of the pressure
stroke, the second sensor can sense that the piston is proximal
thereto and send a signal to the controller to that effect. The
controller can communicate with the pilot valve 186 to redirect the
drive flow through the directional valve 184 so that hydraulic
fluid runs through the first drive line A into the second port 78
of the first pump to reverse the sequence described above.
[0049] In another embodiment, the closed loop circuit can be
arranged to be an intensifier circuit by running a connecting line
173 between the second hydraulic ports 78 of the pumps 50, 51 and
running first and second drive lines A', B' to the first hydraulic
ports 60 of the pumps 50, 51. The intensifier ratio can be based
upon the surface area of the end of the plunger in relation to the
surface area of the annulus defined by the part of the piston
portion of the cylinder assembly which extends radially beyond the
plunger. In one embodiment, the ratio of the area of the end of the
plunger to the area of the annulus of the piston is about 2:1. In
yet other embodiments the intensifier ratio can be varied by
changing the diameters of the annulus and/or the end surface of the
plunger.
[0050] Referring to FIGS. 9-20, another embodiment of a pump 250
according to the present invention is shown. The pump 250 includes
a dual-acting cylinder 252 (see FIG. 10). Referring to FIG. 9, the
pump 250 include three tube assemblies 254, 255, 256 which define a
first pressure chamber, a hydraulic chamber, and a second pressure
chamber, respectively. The second tube assembly 255 is disposed
between the first and third tube assemblies 254, 256. The first and
third tube assemblies 254, 256 each have a butt fitting 258 mounted
thereto. The second tube assembly 255 can have a gland assembly
261, 262 mounted at each end thereof. A tie rod assembly 268, which
includes a plurality of tie rods 269 and a plurality of bolts 270
threadedly engaged therewith, can be provided to connect the
various components together. The pump 250 is a dual acting pump in
that the cylinder can movably reciprocate within the tubes under
the influence of a hydraulic fluid selectively entering first and
second hydraulic ports 260, 278 in fluid communication with the
hydraulic chamber defined by the second tube assembly 255 to
alternatingly discharge pressurized fluid from the first and third
tubes 254, 256.
[0051] Referring to FIG. 9, the pump 250 can include a first sensor
port 282 and a second sensor port 283. The sensor ports 282, 283
can be configured to respectively accommodate a sensor that is
configured to detect when the piston portion 296 is in proximity
therewith. The sensors disposed in the first and second sensor
ports 282, 283 can be electrically connected to a controller, as
described above in connection with the pump 50 of FIG. 1, to
selectively control the flow of hydraulic fluid through the first
and second hydraulic ports 260, 278 to reciprocally move the
dual-acting cylinder 252 to alternatingly discharge pressurized
fluid from the first and third tubes 254, 256 through the butt
fittings 258 mounted thereto.
[0052] Referring to FIG. 10, the cylinder assembly 252 can include
first and second plungers 290, 291 and a piston portion 296
interposed between the plungers. Each plunger 290, 291 can be
similar to the plunger 90 of the pump 50 shown in FIGS. 1-7 and as
described above. The piston portion 296 can be similar to the
piston portion 96 of the pump 50 of FIGS. 1-7 as described
above.
[0053] Referring to FIGS. 12 and 13, the first sensor port 282 is
shown. The first sensor port 282 can be similar to the first sensor
port 82 of the pump 50 of FIG. 1. The second sensor port 283, shown
in FIG. 9, can be similar to the first sensor port 282.
[0054] Referring to FIGS. 14 and 15, the first gland assembly 261
is in sealing relationship with the first plunger 290. The second
gland assembly 262 is in sealing contact with the second plunger
291. The first and second gland assemblies 261, 262 can each be
similar to the gland assembly 62 of the pump 50 of FIG. 1. The
piston portion 296 has a larger diameter than either of the
plungers 290, 291 and is disposed within the hydraulic tube 255.
The piston 296 is configured such that it can reciprocate within
the hydraulic tube 255 but cannot enter either of the pressure
tubes 254, 256. The first and second plungers 290, 291 are
configured such that they can enter the first and second pressure
tubes 254, 256, respectively. The entire cylinder assembly 252 can
reciprocate within the tube assemblies such that the first plunger
290 is undergoing a charge stroke while the second plunger 291 is
undergoing a discharge stroke and vice versa.
[0055] Referring to FIG. 16, one of the butt fittings 258 is shown.
In practice, the butt fitting may be rotated about the longitudinal
axis of the pump 250 over a predetermined angle 297, such as
21.degree., for example, from the position shown in FIG. 11.
Referring to FIG. 17, an integrated dual check valve or a suction
and discharge valve cartridge 352 can be disposed within a cavity
354 of each butt fitting 258. The valve cartridge assembly 57 as
shown and described in U.S. Pat. No. 4,878,815 to Stachowiak, which
is incorporated in its entirety herein by this reference, and the
Uni-Valve cartridge assembly sold by Jetstream of Houston LLP are
exemplary valves for use as the valve cartridge 352. The butt
fitting 258 can have an inlet port 356 for admitting fluid to be
pressurized within the pressure tube 254 to which the butt fitting
258 is mounted and an outlet port 357 for allowing pressurized
fluid to leave the pressure tube 254 for use downstream of the
pump. The valve cartridge 352 is disposed between the inlet and
outlet ports 356, 357 and the pressure tube to selectively allow
and prevent fluid flow therethrough such that fluid can flow from
the inlet port to the tube, but not to the outlet port, and fluid
can flow from the tube to the outlet port, but not to the inlet
port.
[0056] Referring to FIG. 18, the butt fitting 258 is shown with the
valve cartridge 352 removed therefrom. The inlet port 356 is in
communication with the cavity 354. The cavity 354 includes a weep
hole 258 to provide an indicator in the event the valve cartridge
fails. The cavity 354 includes a stepped configuration to retain
the valve cartridge therein.
[0057] Referring to FIG. 19, the first plunger 290 closely conforms
to the first tube 254. Referring to FIG. 20, the second plunger 291
is relatively smaller than the hydraulic tube 255. The second
plunger 291 can closely conform to the second pressure tube.
[0058] Referring to FIG. 21, in other embodiments of the pump, a
check valve 353 can be paired with another similar check valve in
lieu of the integrated dual check valve 352 shown in FIG. 17. The
check valve 353 shown in FIG. 21 is an example of a suitable check
valve for use with the pump and is similar to the valve which has
been commercialized by National Oil Well and is similar to the
valve shown and described in U.S. Pat. No. 4,667,697, entitled
"Unitized Check Valve," which is incorporated in its entirety
herein by this reference.
[0059] Referring to FIG. 21, another embodiment of a closed loop
pump circuit 370 is shown. The circuit 370 can include a charge
pump 376, an electrical control package 378 including a plurality
of proportional solenoids 379, a swash plate 381 configured to
change position in response to the movement of the solenoids 379, a
relief valve 383 for the charge pump 376, a hot oil shuttle 385
hydraulically connected to the charge pump 376, and a dual acting
pump 250, as shown in FIG. 9, hydraulically connected to the charge
pump 376. The sensors of the pump 250 can be electrically connected
to the control package 378 to position the swash plate 381 such
that the charge pump 376 is feeding hydraulic fluid to the low side
of the loop in order to reciprocate the cylinder assembly 252
within the pump 250 such that pressurized fluid is alternatingly
discharged from the first and second pressure tubes 254, 256.
[0060] In yet other embodiments of a closed loop circuit, the
rodder pump 250 can be used in a de-intensifier circuit wherein the
pressure of the hydraulic fluid used to reciprocate the pump 250 is
higher than the pressure of the fluid alternately discharged from
the first and second pressure chambers. For example, the hydraulic
fluid can be at a pressure of about 5 kpsi and the water discharged
from the first and second pressure chambers can be at a pressure of
about 3 kpsi. In such a situation, a relatively smaller amount of
hydraulic fluid can be used than the amount of water that can be
discharged from the pump.
[0061] In some embodiments of the dual-acting pump, four sensor
ports and four corresponding sensors can be provided. Two of the
four sensors can be disposed in sensor ports disposed as shown in
FIG. 9 to monitor the location of the piston assembly of the
cylinder. The other two sensor ports, and accompanying sensors, can
be respectively disposed adjacent the butt fittings 258 such that
they detect the presence of the distal end of the first and second
plungers, respectively. The third and fourth sensors can detect
when the first and second plungers are disposed at the end of their
respective discharge stroke and can help to keep the pump in phase.
The sensors can also be used to monitor the amount of time it takes
for each plunger to travel over its discharge stroke, for example.
By disposing the sensors a predetermined amount away from each
other, the speed of the plunger can be determined once the time of
stroke travel is known. With the pressure tubes being configured to
have a predetermined area, the flow rate of fluid from the pump can
be computed. This information, along with a cycle count, can be
displayed via an LCD, for example, that is electrically connected
to the controller.
[0062] In yet other embodiments of the pump, the external sensors
can be replaced by an inductive sensor system, such as a linear
variable differential transformer (LVDT) system or a linear
velocity transducer (LVT) system, for example, with the inductive
sensor comprising a plurality of coils and a core, one of which
being mounted to or comprising the plunger of the cylinder of the
pump and the other of which mounted to or comprising a portion of
the tube assembly within which the plunger is disposed. The
inductive sensor system can include an extension rod made of a
non-ferrous material, such as non-magnetic stainless steel, for
example. For embodiments having a rodder pump with the dual-acting
cylinder, a pair of inductive sensor systems can be provided for
each plunger and tube combination.
[0063] The inductive sensor can detect the location of the plunger
or plungers over the entire stroke of the cylinder and transmit
that information to a controller via an electrical connection
therewith. The inductive sensor can provide data to the controller
relating to the instant position of the cylinder within the tube
assembly such that the controller can provide an output of the
instantaneous flow rate developed by the pump.
[0064] The inductive sensor system can be electrically connected to
a controller that is configured to provide a buffered transition
when the cylinder changes direction. The controller can be
configured to change the flow of hydraulic fluid to the hydraulic
ports over a time gradient based on the location of the cylinder as
detected by the inductive sensor system such that the velocity of
the cylinder gradually decreases until the cylinder changes
direction, which also can be detected by the inductive sensor
system. Any suitable LVDT system or LVT system can be used as the
inductive sensor system with the rodder pump of the present
invention.
[0065] Referring to FIG. 23, a vehicle 400 for cleaning sewer pipes
and/or catch basins is shown. The vehicle 400 can include a
debris-collecting dump body 402, a vacuum hose 404 connected
thereto, and a vacuum operably connected to the vacuum hose line
404 such that debris can be collected via the vacuum hose 404 and
collected in the body 402. The vehicle 400 can also include a
multi-stage blower filtration system 406, disposed between the
vacuum and the vacuum hose 404, that can act to prevent debris from
entering the vacuum blower. The filtration system 406 can include a
centrifugal cyclone 408 and a stainless steel screen strainer 410
for filtering debris from the vacuum. The screen strainer 410 can
act to remove particles as small as 10 microns, for example. The
vacuum hose 404 can be mounted to a hydraulic boom 412 that is
pivotally connected to the vehicle chassis. The boom 412 can also
be extendable up to a predetermined amount.
[0066] The vehicle 400 can also include a cleaning system 420 that
comprises a front-mounted hose reel 422 that includes a
predetermined length of water hose wound thereon, a control panel
424 disposed adjacent the reel 422 for use by an operator to
operate the cleaning system 420, a pair of water tanks 424,
respectively disposed on either side of the vehicle 400, a
hydraulically driven water pump 426 in fluid communication with the
water. tanks 424, and a rodder pump 250, as shown in FIG. 9, in
fluid communication with the water pump 426 by any suitable water
lines. The water lines can connect the butt fittings of the rodder
pump to the water pump 426 to allow water to be alternately pumped
into the first and second pressure chambers of the rodder pump 250
from the water tanks during the suction stroke of the first and
second plungers, respectively. Each of the butt fittings of the
pump 250 can also be fluidly connected, via a common feed line, for
example, to the length of hose wound on the hose reel 422 such that
pressurized water can alternately exit the butt fittings during the
discharge stroke of the first and second plungers, respectively.
The pressurized water can move through the common feed line to the
water hose, and ultimately exit the distal free end of the length
of hose. The first and second hydraulic ports of the pump 250 can
be hydraulically connected to a hydraulic supply of the vehicle to
reciprocally move the cylinder. The distal end of the hose can also
support any of a number of tools to facilitate the cleaning of the
sewer, such as, a self-propelling jet nozzle, for example. The
dual-acting pump 250 can be disposed at the rear end of the vehicle
400. The pump 250 can be arranged in any suitable fluid circuit,
such as any described herein above.
[0067] The water hose can be unwound from the reel 422 and fed into
a sewer, for example. The operator can use the control panel 424 to
control the unwinding of the water hose from the reel 422. The
operator can activate the water pump and the hydraulic supply such
that the water pump operates to pump water to the rodder pump 250
and the hydraulic supply selectively feeds hydraulic fluid to the
first and second hydraulic ports of the rodder pump 250 to
reciprocally move the dual-acting cylinder to generate pressurized
water which, in turn, can be dispensed from the water hose to clean
the sewer.
[0068] The vehicle 400 can be any suitable vehicle, such as the
Vactor.RTM. 2100 Series positive displacement sewer cleaner sold by
Vactor Manufacturing, Inc. of Streator, Ill. In yet other
embodiments, the pump according to the present invention can be
used as part of a water excavator. Other suitable vehicles, and
components thereof, are shown and described in U.S. Pat. Nos.
3,658,589; RE34,585; and 6,792,646, the entire disclosures thereof
being incorporated herein in their entireties by this
reference.
[0069] Referring to FIG. 24, another embodiment of a rodder pump
550 according to the present invention is shown. The rodder pump
550 includes a dual-acting cylinder 552 and is similar to the
rodder pump 250 shown in FIG. 9 and described above. The rodder
pump include three tube assemblies 554, 555, 556 that respectively
define a first pressure chamber, a hydraulic chamber, and a second
pressure chamber. The rodder pump 550 includes first and second
blocks 572, 573 disposed at the distal ends of the first and third
tube assemblies 554, 556.
[0070] Each block 572, 573 includes appropriate valving to allow
fluid to alternatingly enter the first and second pressure
chambers, respectively, via an inlet port 574. Water can be drawn
into a particular pressure chamber when the plunger of the cylinder
552 that is disposed in the particular pressure chamber is
undergoing a suction stroke. The inlet ports 574 can be fluidly
connected to a vehicle-mounted water pump that is operable to pump
water stored in tanks of the vehicle to the rodder pump 550 to
provide the supply of fluid to the rodder pump 550.
[0071] Each block 572, 573 includes appropriate valving to allow
fluid to alternatingly discharge from the first and second pressure
chambers, respectively, via an outlet port 575. Water can be
discharged from a particular pressure chamber when the plunger of
the cylinder 552 that is disposed in the particular pressure
chamber is undergoing a discharge stroke. The outlet ports 575 can
be fluidly connected to a common feed 576 that is operably
connected to a vehicle-mounted water hose line to deliver
pressurized water for sewer cleaning applications, for example.
[0072] All references, including publications, patent applications,
and patents, cited herein are hereby incorporated by reference to
the same extent as if each reference were individually and
specifically indicated to be incorporated by reference and were set
forth in its entirety herein.
[0073] The use of the terms "a" and "an" and "the" and similar
referents in the context of describing the invention (especially in
the context of the following claims) are to be construed to cover
both the singular and the plural, unless otherwise indicated herein
or clearly contradicted by context. The terms "comprising,"
"having," "including," and "containing" are to be construed as
open-ended terms (i.e., meaning "including, but not limited to,")
unless otherwise noted. Recitation of ranges of values herein are
merely intended to serve as a shorthand method of referring
individually to each separate value falling within the range,
unless otherwise indicated herein, and each separate value is
incorporated into the specification as if it were individually
recited herein. All methods described herein can be performed in
any suitable order unless otherwise indicated herein or otherwise
clearly contradicted by context. The use of any and all examples,
or exemplary language (e.g., "such as") provided herein, is
intended merely to better illuminate the invention and does not
pose a limitation on the scope of the invention unless otherwise
claimed. No language in the specification should be construed as
indicating any non-claimed element as essential to the practice of
the invention.
[0074] Preferred embodiments of this invention are described
herein, including the best mode known to the inventors for carrying
out the invention. Variations of those preferred embodiments may
become apparent to those of ordinary skill in the art upon reading
the foregoing description. The inventors expect skilled artisans to
employ such variations as appropriate, and the inventors intend for
the invention to be practiced otherwise than as specifically
described herein. Accordingly, this invention includes all
modifications and equivalents of the subject matter recited in the
claims appended hereto as permitted by applicable law. Moreover,
any combination of the above-described elements in all possible
variations thereof is encompassed by the invention unless otherwise
indicated herein or otherwise clearly contradicted by context.
* * * * *