U.S. patent application number 09/929719 was filed with the patent office on 2002-03-07 for high-pressure fluid-jet cutting device and method with abrasive removal system.
Invention is credited to Massenburg, John C..
Application Number | 20020028634 09/929719 |
Document ID | / |
Family ID | 22087537 |
Filed Date | 2002-03-07 |
United States Patent
Application |
20020028634 |
Kind Code |
A1 |
Massenburg, John C. |
March 7, 2002 |
High-pressure fluid-jet cutting device and method with abrasive
removal system
Abstract
A fluid jet-cutting machine with an abrasive particle removal
device and method. In one embodiment, the fluid-jet cutting machine
has a nozzle and a carrier assembly attached to the nozzle to move
the nozzle along a cutting path. A high-pressure fluid source and
an abrasive particle source are coupled to the nozzle to generate
an abrasive fluid-jet having a fluid and a plurality of abrasive
particles for cutting a work-piece. The cutting machine also has a
particle removal including, tank aligned with the nozzle, a
settling container, and a fluid transport mechanism to transport
fluid from the tank to the settling container. The tank includes at
least one compartment configured to receive the fluid and the
abrasive particles of the fluid-jet along at least a portion of the
cutting path. Additionally, the compartment is configured to
control fluid flow within the compartment so that the fluid-jet
suspends, and maintains the suspension, of at least a substantial
portion of the abrasive particles in the one compartment without
additional mechanical agitation. The fluid transport mechanism can
include a conduit with a first end in fluid communication with the
compartment and a second end outside of the compartment in fluid
communication with the settling container. In operation, a portion
of the fluid with suspended abrasive particles in the compartment
is transported through the conduit and into the settling container.
The abrasive particles from the transported portion of fluid settle
to a lower portion of the settling container while a clarified
fluid is removed from the settling container.
Inventors: |
Massenburg, John C.;
(Seattle, WA) |
Correspondence
Address: |
SEED INTELLECTUAL PROPERTY LAW GROUP PLLC
701 FIFTH AVE
SUITE 6300
SEATTLE
WA
98104-7092
US
|
Family ID: |
22087537 |
Appl. No.: |
09/929719 |
Filed: |
August 13, 2001 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
09929719 |
Aug 13, 2001 |
|
|
|
09069223 |
Apr 28, 1998 |
|
|
|
6299510 |
|
|
|
|
Current U.S.
Class: |
451/38 ; 451/36;
451/89; 451/91 |
Current CPC
Class: |
B26F 3/008 20130101;
Y02P 70/179 20151101; Y02P 70/10 20151101; B24C 9/003 20130101;
B24C 9/006 20130101; B24C 1/045 20130101 |
Class at
Publication: |
451/38 ; 451/36;
451/89; 451/91 |
International
Class: |
B24B 001/00; B24C
001/00 |
Claims
1. A fluid-jet cutting machine, comprising: a nozzle adapted to be
coupled to a high-pressure fluid source and an abrasive particle
delivery device, the nozzle being configured to project an abrasive
fluid-jet; a carrier assembly attached to the nozzle to move the
nozzle and the fluid-jet along a cutting path; a tank aligned with
the nozzle, the tank including at least one compartment configured
to receive the fluid and the abrasive particles of the fluid-jet
along at least a portion of the cutting path and to control fluid
flow out of the one compartment, the controlled fluid flow of the
one compartment and the fluid-jet maintaining at least a
substantial portion of the abrasive particles in suspension in the
fluid in the one compartment without additional mechanical
agitation; a fluid transport mechanism including a conduit, the
conduit having a first end in fluid communication with the one
compartment and a second end outside of the one compartment; and a
settling container separate from the one compartment, the second
end of the conduit being in fluid communication with the settling
container, a portion of the fluid with suspended abrasive particles
in the one compartment being transported through the conduit from
the one compartment into the settling container, and the abrasive
particles from the transported portion of fluid settling to a lower
portion of the settling container while a clarified fluid is
removed from the settling container through an outlet of the
settling container.
2. The fluid-jet cutting machine of claim 1 wherein the first end
of the conduit is positioned at a lower portion of the one
compartment and the second end of the conduit is positioned below
the first end and in the settling container, the fluid and the
abrasive particles suspended in the fluid flowing through the
conduit from the one compartment to the settling container under
the influence of gravity.
3. The fluid-jet cutting machine of claim 1 wherein the fluid
transport mechanism further comprises a fluid drive system coupled
to the conduit, the fluid drive system driving fluid and abrasive
particles suspended in the fluid through the conduit to the
settling container.
4. The fluid-jet cutting machine of claim 3 wherein: the first end
of the conduit is positioned in a lower portion of the one
compartment; and the fluid drive system comprises a pressurized gas
source attached to the conduit at a location below a fluid level in
the one compartment, a gas from the pressurized gas source being
injected into the conduit and the gas rising through at least a
portion of the conduit, the rising gas drawing fluid and abrasive
particles suspended in the fluid through the conduit from the one
compartment to the settling container.
5. The fluid-jet cutting machine of claim 4 wherein the fluid drive
system further comprises a back-flush valve in the conduit between
the second end and the location of attachment of the pressurized
gas source, the back-flush valve being positionable in an open
position to allow fluid to flow through the conduit and a closed
position to allow pressure to build in the conduit for clearing a
blockage of abrasive particles from the first end of the
conduit.
6. The fluid-jet cutting machine of claim 1 wherein the tank
further includes a plurality of compartments and the cutting path
moves with respect to the tank to pass across at least two of the
plurality of the compartments, each compartment being configured to
receive the fluid and the abrasive particles from the fluid-jet as
the fluid-jet passes across each compartment and to control fluid
flow to an adjacent compartment, and, while the fluid-jet passes
across one of the compartments, the controlled fluid flow of the
one of the compartments and the fluid-jet maintaining at least a
substantial portion of the abrasive particles in suspension in the
fluid in the one of the compartments without additional mechanical
agitation.
7. The fluid-jet cutting machine of claim 6 wherein the tank
comprises: a bottom panel, a first side-wall projecting from one
side of the bottom panel, a second side-wall projecting from
another side of the bottom panel and juxtaposed to the first
side-wall, a first end-wall projecting from one end of the bottom
panel, and a second end-wall projecting from another end of the
bottom panel and juxtaposed to the first end-wall, the first and
second end-walls being attached to the first and second side-walls;
and at least one divider extending across the tank between one of
side-walls or the end-walls to divide the tank into at least two
compartments.
8. The fluid-jet cutting machine of claim 7 wherein the divider
comprises a baffle around which a restricted fluid flow may pass
from a first compartment to an adjacent second compartment.
9. The fluid-jet cutting machine of claim 6 wherein: the tank
comprises at least a first compartment and a second compartment;
the conduit comprises at least a first conduit section and a second
conduit section, the first conduit section having a first end
positioned in a lower portion of the first compartment and a second
end positioned in the second compartment, the second conduit
section having a first end positioned in a lower portion of the
second compartment and located to receive a first fluid flow from
the first conduit section, and the second conduit section further
including a second end open to the settling container; and the
fluid transport system further comprises a fluid drive system
coupled to the first and second conduit sections, the fluid drive
system driving the first fluid flow through the first conduit
section from the first compartment to the second compartment, and
the fluid drive system driving a second fluid flow through the
second conduit section from the second compartment to the settling
container.
10. The fluid-jet cutting machine of claim 9 wherein the fluid
drive system comprises: a pressurized gas source; and a gas line
coupled to the gas source, the gas line having a first segment
attached to the first conduit section a location below a fluid
level in the first compartment, and the gas line having a second
segment attached to the second conduit section at a location below
a fluid level of the second compartment, a gas from the pressurized
gas source being injected into the first and second conduit
sections and the gas rising through the conduit sections to draw
the first and second fluid flows through the first and second
conduit sections, respectively.
11. The fluid-jet cutting machine of claim 10 wherein the fluid
drive system further comprises: a first back-flush valve in the
first conduit section between the second end of the first conduit
section and the location of attachment of the first gas line, the
first back-flush valve being positionable in an open position to
allow the first fluid flow through the first conduit section and a
closed position to allow pressure to build in the first conduit
section for clearing a blockage of abrasive particles from the
first end of the first conduit section; and a second back-flush
valve in the second conduit section between the second end of the
second conduit section and the location of attachment of the second
gas line, the second back-flush valve being positionable in an open
position to allow the second fluid flow through the second conduit
section and a closed position to allow pressure to build in the
second conduit section for clearing a blockage of abrasive
particles from the first end of the second conduit section.
12. An abrasive particle removal device for use with a fluid-jet
cutting machine having a nozzle, a high-pressure fluid source and
an abrasive particle source coupled to the nozzle to generate a
fluid-jet having a fluid and a plurality of abrasive particles, and
a carrier assembly attached to the nozzle to move the nozzle along
a cutting path, the particle removal device comprising: a tank
aligned with the nozzle, the tank including at least one
compartment configured to receive the fluid and the abrasive
particles of the fluid-jet along at least a portion of the cutting
path and to control fluid flow out of the one compartment, the
controlled fluid flow of one compartment and the fluid-jet
maintaining at least a substantial portion of the abrasive
particles in suspension in the fluid in the one compartment without
additional mechanical agitation; a fluid transport mechanism
including a conduit, the conduit having a first end in fluid
communication with the one compartment and a second end outside of
the one compartment; and a settling container separate from the one
compartment, the second end of the conduit being in fluid
communication with the settling container, a portion of the fluid
with suspended abrasive particles in the one compartment being
transported through the conduit from the one compartment into the
settling container, and the abrasive particles from the transported
portion of fluid settling to a lower portion of the settling
container while a clarified fluid is removed from the settling
container through an outlet of the settling container.
13. The removal device of claim 12 wherein the first end of the
conduit is positioned at a lower portion of the one compartment and
the second end of the conduit is positioned below the first end and
in the settling container, the fluid and the abrasive particles
suspended in the fluid flowing through the conduit from the one
compartment to the settling container under the influence of
gravity.
14. The removal device of claim 12 wherein the fluid transport
mechanism further comprises a fluid drive system coupled to the
conduit, the fluid drive system driving fluid and abrasive
particles suspended in the fluid through the conduit to the
settling container.
15. The removal device of claim 14 wherein: the first end of the
conduit is positioned in a lower portion of the one compartment;
and the fluid drive system comprises a pressurized gas source
attached to the conduit at a location below a fluid level in the
one compartment, a gas from the pressurized gas source being
injected into the conduit and the gas rising through at least a
portion of the conduit, the rising gas drawing fluid and abrasive
particles suspended in the fluid through the conduit from the one
compartment to the settling container.
16. The removal device of claim 15 wherein the fluid drive system
further comprises a back-flush valve in the conduit between the
second end and the location of attachment of the pressurized gas
source, the back-flush valve being positionable in an open position
to allow fluid to flow through the conduit and a closed position to
allow pressure to build in the conduit for clearing a blockage of
abrasive particles from the first end of the conduit.
17. The removal device of claim 14 wherein: the first end of the
conduit is positioned in a lower portion of the one compartment;
and the fluid drive system comprises a pump attached to the
conduit, the pump driving fluid through the conduit from the one
compartment to the settling container.
18. The removal system of claim 17 wherein the pump comprises a
diaphragm pump.
19. The removal device of claim 14 wherein: the first end of the
conduit is positioned in a lower portion of the one compartment;
and the fluid drive system comprises a motor with a drive shaft and
an impeller attached to the drive shaft, the impeller being
positioned with respect to the conduit to drive fluid through the
conduit from the one compartment to the settling container.
20. The removal device of claim 12 wherein the tank further
includes a plurality of compartments and the cutting path moves
with respect to the tank to pass across at least two of the
plurality of the compartments, each compartment being configured to
receive the fluid and the abrasive particles from the fluid-jet as
the fluid-jet passes across each compartment and to control fluid
flow to an adjacent compartment, and, while the fluid-jet passes
across one of the compartments, the controlled fluid flow of the
one of the compartments and the fluid-jet maintaining at least a
substantial portion of the abrasive particles in suspension in the
fluid in the one of the compartments without additional mechanical
agitation.
21. The removal device of claim 20 wherein the tank comprises a
bottom panel, a side-wall projecting from the bottom panel to
define a reservoir, and at least one divider in the reservoir to
divide the tank into at least two compartments.
22. The removal device of claim 20 wherein the tank comprises: a
bottom panel, a first side-wall projecting from one side of the
bottom panel, a second side-wall projecting from another side of
the bottom panel and juxtaposed to the first side-wall, a first
end-wall projecting from one end of the bottom panel, and a second
end-wall projecting from another end of the bottom panel and
juxtaposed to the first end-wall, the first and second end-walls
being attached to the first and second side-walls; and at least one
divider extending across the tank between one of side-walls or the
end-walls to divide the tank into at least two compartments.
23. The removal device of claim 22 wherein the divider comprises a
baffle around which a restricted fluid flow may pass from a first
compartment to an adjacent second compartment.
24. The removal device of claim 20 wherein: the tank comprises at
least a first compartment and a second compartment; the conduit
comprises at least a first conduit section and a second conduit
section, the first conduit section having a first end positioned in
a lower portion of the first compartment and a second end
positioned in the second compartment, the second conduit section
having a first end positioned in a lower portion of the second
compartment and located to receive a first fluid flow from the
first conduit section, and the second conduit section further
including a second end open to the settling container; and the
fluid transport system further comprises a fluid drive system
coupled to the first and second conduit sections, the fluid drive
system driving the first fluid flow through the first conduit
section from the first compartment to the second compartment, and
the fluid drive system driving a second fluid flow through the
second conduit section from the second compartment to the settling
container.
25. The removal device of claim 24 wherein the fluid drive system
comprises: a pressurized gas source; and a gas line coupled to the
gas source, the gas line having a first segment attached to the
first conduit section a location below a fluid level in the first
compartment, and the gas line having a second segment attached to
the second conduit section at a location below a fluid level of the
second compartment, a gas from the pressurized gas source being
injected into the first and second conduit sections and the gas
rising through the conduit sections to draw the first and second
fluid flows through the first and second conduit sections,
respectively.
26. The removal device of claim 25 wherein the fluid drive system
further comprises: a first back-flush valve in the first conduit
section between the second end of the first conduit section and the
location of attachment of the first gas line, the first back-flush
valve being positionable in an open position to allow the first
fluid flow through the first conduit section and a closed position
to allow pressure to build in the first conduit section for
clearing a blockage of abrasive particles from the first end of the
first conduit section; and a second back-flush valve in the second
conduit section between the second end of the second conduit
section and the location of attachment of the second gas line, the
second back-flush valve being positionable in an open position to
allow the second fluid flow through the second conduit section and
a closed position to allow pressure to build in the second conduit
section for clearing a blockage of abrasive particles from the
first end of the second conduit section.
27. The removal device of claim 20 wherein: the tank comprises at
least a first compartment and a second compartment; the conduit
comprises a main section, a first conduit section coupled to the
main section, and a second conduit section also coupled to the main
section, the first conduit section having a first end positioned in
a lower portion of the first compartment and a second end attached
to the main section, the second conduit section having a first end
positioned in a lower portion of the second compartment and a
second end attached to the main section, and the main section
having a discharge end open to the settling container; and the
fluid transport system further comprises a fluid drive system
coupled to at least one of the first, the second and the main
conduit sections, the fluid drive system driving a first fluid flow
through the first conduit section from the first compartment to the
main section, and the fluid drive system driving a second fluid
flow through the second conduit section from the second compartment
to the main section, the first and second fluid flows passing
through the discharge end of the main section to the settling
container.
28. The removal device of claim 20 wherein: the tank comprises at
least a first compartment and at least a second compartment; the
conduit comprises a first conduit section extending from the first
compartment directly to the settling container and a second conduit
section extending from the second compartment directly to the
settling container, the first conduit section having a first end
positioned in a lower portion of the first compartment and a second
end open to the settling container, the second conduit section
having a first end positioned in a lower portion of the second
compartment and a second end open to the settling container; and
the fluid transport system further comprises a fluid drive system
coupled to the first and second conduit sections, the fluid drive
system driving a first fluid flow through the first conduit section
from the first compartment to the settling container, and the fluid
drive system driving a second fluid flow through the second conduit
section from the second compartment to the settling container.
29. The removal system of claim 12 wherein the settling container
comprises: a drum having a rim defining an opening of the drum; and
a detachable shroud attached to the drum, the second end of the
conduit being attached to the shroud to deposit the transported
portion of the fluid into the drum, and the outlet of the settling
container being positioned in the shroud, wherein the abrasive
particles accumulate in the drum, and when the drum is full, the
shroud is removed from the drum to be placed on another empty
drum.
30. A method of operating a fluid-jet cutting machine, comprising:
projecting an abrasive fluid-jet having a plurality of abrasive
particles in a fluid through a work-piece and into a compartment of
a tank; maintaining a significant portion of abrasive particles in
suspension in the fluid in the compartment without mechanical
agitation other than the fluid-jet; transporting a portion of the
fluid with suspended abrasive particles from the compartment to a
settling container; and settling abrasive particles from the
transported portion of fluid to leave an accumulation of abrasive
particles in a lower portion of the settling container and a
clarified liquid above the accumulation of abrasive particles in
the settling container.
31. The method of claim 30 wherein transporting the fluid comprises
injecting a pressurized gas into a conduit section in the
compartment below a fluid level in the compartment, the injected
gas rising through a portion of the conduit section to generate a
fluid flow through the conduit section that draws abrasive
particles out of the compartment.
32. The method of claim 30 wherein transporting the fluid comprises
pumping a fluid through a conduit section to draw suspended
abrasive particles out of the compartment.
33. The method of claim 30 wherein: the fluid-jet cutting machine
includes a catch tank with at least a first compartment and a
second compartment, and a fluid transport system with a first
conduit section having a first end in the first compartment and a
second end in the second compartment, and a second conduit section
having a first end in the second compartment and a second end
coupled to the settling container; and transporting the fluid
comprises injecting a fluid into the first conduit section to
generate a first flow and injecting a fluid into the second conduit
section to generate a second flow, the first flow drawing abrasive
particles from the first compartment and the second flow drawing
abrasive particles from at least the second compartment.
34. The method of claim 33 wherein injecting a fluid into the
conduit sections comprises: pressurizing a gas; and introducing the
gas into the conduit sections below a fluid level.
35. The method of claim 33 wherein injecting a fluid into the
conduit sections comprises pumping a liquid through the conduit
sections.
36. The method of claim 30, further comprising clearing an inlet of
a conduit between the compartment and the settling container of an
accumulation of abrasive particles.
37. The method of claim 36 wherein clearing the conduit inlet
comprises: closing a back-flush valve in the conduit; and injecting
air into the conduit between the back-flush valve and the abrasive
particle accumulation, the injected air blowing the abrasive
particle accumulation from the inlet of the conduit.
Description
TECHNICAL FIELD
[0001] The present invention relates to fluid-jet cutting devices
and methods, and more particularly to such devices including an
abrasive removal system.
BACKGROUND OF THE INVENTION
[0002] Fluid-jet cutting devices are often used to cut metal parts,
fiber-cement siding, stone and many other materials. A typical
fluid-jet cutting machine has a high-pressure pump to provide a
high-pressure fluid source, and a nozzle is coupled to the
high-pressure fluid source to generate a cutting-jet from the
nozzle. The nozzle is also attached to a carrier assembly that
moves the nozzle along a desired cutting path, and a catch tank is
aligned with the nozzle throughout the cutting path. An abrasive
particle source may be coupled to the nozzle to impart abrasive
particles to the cutting-jet. The fluid is typically water, and the
abrasive particles are typically garnet.
[0003] In operation of such a fluid-jet cutting machine, a
work-piece is positioned between the nozzle and the catch tank. The
carrier assembly moves the nozzle along the cutting path, and the
high-pressure fluid source and abrasive particle source generate an
abrasive cutting-jet projecting from the nozzle. As the cutting-jet
passes through the work-piece, the catch tank receives the
wastewater and abrasive particles of the spent cutting jet The
abrasive particles generally accumulate in the catch tank, and the
waste water generally flows out of the catch tank.
[0004] One concern with fluid-jet cutting systems is that the
abrasive particles must be removed from the catch tank. The devices
and methods for removing abrasive particles from catch tanks
typically depend upon the size of the catch tanks. In general,
small catch tanks are typically less than 2'.times.4', and large
catch tanks are typically greater than 4'.times.8'.
[0005] Conventional techniques for removing abrasive particles from
small catch tanks generally allow the wastewater to simply overflow
the small catch tanks. Although a portion of the abrasive particles
are removed from small catch tanks with the overflowing wastewater,
abrasive particles still accumulate in small catch tanks. The
remaining abrasive particles are typically removed from small catch
tanks by: (1) stopping the cutting-jet to allow the abrasive
particles to settle; and (2) shoveling or dumping the abrasive
particles from the catch tank.
[0006] One problem with conventional techniques for removing
abrasive particles from small catch tanks is that the cutting
machine must be shut down for a period of time to allow the
abrasive particles to settle. Removing abrasive particles from
small catch tanks may accordingly result in a significant amount of
down-time in a cutting operation. Another problem with removing
abrasive particles from small catch tanks is that it is
inconvenient and labor intensive to shovel or dump the abrasive
particles from the tanks. Therefore, removing abrasive particles
from small catch tanks reduces the efficiency and productivity of
fluid-jet cutting processes.
[0007] Conventional techniques for removing abrasive particles from
large catch tanks are different than those for small catch tanks.
One conventional abrasive removal system for large catch tanks is a
conveyor rake that moves across the bottom of a large catch tank
and up a discharge side of the tank. To most effectively operate a
conveyor rake, the abrasive particles must settle to the bottom of
the tank. The conveyor then carries the abrasive particles from the
bottom of the tank and over the discharge side of the tank. One
potential problem with conveyor rakes, therefore, is that they may
need to be operated when the cutting-jet is shut down causing
down-time. Another problem with conveyor rakes is that they may be
cut by the cutting-jet during the cutting process if the
cutting-jet passes over the portion of the conveyor rake at the
discharge side of the catch tank. Additionally, conveyor rake
removal systems may be relatively expensive units with many moving
components that may fail after extended use. Thus, conveyor rake
systems for removing abrasive particles from large catch tanks have
several drawbacks.
[0008] Another conventional system for removing abrasive particles
from large catch tanks is a continuous centrifugal system that has
a large pump in the catch tank and a centrifugal separator outside
of the catch tank. The large pump agitates the wastewater to
suspend the abrasive particles in the catch tank. The wastewater
and the suspended abrasive particles are then pumped to a
centrifuge, such as a hydrocyclone separator, to separate the
abrasive particles from the wastewater. One drawback of this device
is that large, expensive pumps are required to maintain the
abrasive particles in suspension in the wastewater. Another
drawback of this abrasive removal system is that a significant
amount of energy is required to operate such large pumps.
Additionally, hydrocyclone separators are also relatively costly
devices that require additional resources to operate and maintain.
Thus, centrifugal removal systems also have several drawbacks.
SUMMARY OF THE INVENTION
[0009] The invention is generally directed toward fluid jet-cutting
machines and abrasive particle removal devices. In one embodiment,
a fluid-jet cutting machine has a nozzle and a carrier assembly
that moves the nozzle along a cutting path. A high-pressure fluid
source and an abrasive particle source are coupled to the nozzle to
generate an abrasive cutting-jet having a fluid and a plurality of
abrasive particles. In general, the fluid can be water and the
abrasive particles can be composed of garnet.
[0010] The cutting machine also has a particle removal device
including a tank aligned with the nozzle, a settling container, and
a fluid transport mechanism to transport fluid from the tank to the
settling container. The tank includes at least one compartment
configured to receive the fluid and the abrasive particles of the
cutting-jet along at least a portion of the cutting path.
Additionally, the compartment is configured to control fluid flow
within the tank so that the cutting-jet continuously suspends at
least a substantial portion of the abrasive particles in the one
compartment without additional mechanical agitation. The
compartment itself, for example, can be sized and/or shaped so that
the jet energy alone maintains the abrasive particles in
suspension. The fluid transport mechanism can include a conduit
with a first end in fluid communication with the compartment and a
second end outside of the compartment in fluid communication with
the settling container.
[0011] In operation, a portion of the fluid with suspended abrasive
particles in the compartment is transported through the conduit and
into the settling container. For example, a fluid drive system may
be coupled to the conduit to draw fluid from the compartment and
through the conduit. The abrasive particles from the transported
portion of fluid settle to a lower portion of the settling
container while a clarified fluid is removed from the settling
container. The clarified fluid may also be pumped back to the catch
tank.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a schematic isometric view of a fluid-jet cutting
machine with a cut-away view of one embodiment of an abrasive
particle removal system.
[0013] FIG. 2 is a partial cross-sectional view of the abrasive
removal system of the fluid-jet cutting machine shown in FIG.
1.
[0014] FIG. 3 is a partial cross-sectional view of another
embodiment of an abrasive particle removal system for a fluid-jet
cutting machine.
[0015] FIG. 4 is a partial cross-sectional view of another
embodiment of an abrasive particle removal system for a fluid-jet
cutting machine.
[0016] FIG. 5 is a partial cross-sectional view of another
embodiment of an abrasive particle removal system for a fluid-jet
cutting machine.
[0017] FIG. 6 is a partial cross-sectional view of another
embodiment of an abrasive particle removal system for a fluid-jet
cutting machine.
[0018] FIG. 7 is a schematic isometric view of another fluid-jet
cutting machine with a cut-away view of another embodiment of an
abrasive particle removal system.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The present invention is directed toward devices and methods
for removing abrasive particles from fluid-jet cutting machines.
Many specific details of certain embodiments of the invention are
set forth in the following description and in FIGS. 1-7 to provide
a thorough understanding of such embodiments. One skilled in the
art, however, will understand that the present invention may have
additional embodiments, or that the invention may be practiced
without several of the details described in the following
description.
[0020] FIG. 1 is a schematic isometric view of a fluid-jet cutting
machine 10. In this embodiment, the cutting machine 10 includes a
cutting head 20 with a carrier assembly 21 and a nozzle 22 attached
to the carrier assembly 20. A high-pressure fluid source 24 and an
abrasive particle source 26 are coupled to the nozzle 22 to
generate an abrasive cutting-jet 28 projecting from the nozzle 22.
Additionally, the cutting machine 10 also includes a work-piece
support structure 30 with a number of support members or beams 32
attached to a frame 33. In operation, the carrier assembly 21 moves
the nozzle 22 along desired X-Y coordinates (arrows M) to move the
cutting-jet 28 along a desired cutting path P with respect to a
work-piece W. One suitable cutting head 20 is the Bengal 4.times.4
and Paser 3 System manufactured by Flow International Corporation
of Kent, Wash.
[0021] The cutting machine 10 also includes an abrasive particle
removal system 40. In one embodiment, the abrasive particle
removing system 40 has a catch tank 42 under the support structure
30, a fluid transport mechanism 44 in the catch tank 42, and a
settling container 46 coupled to the fluid transport mechanism 44.
As described in greater detail below, the abrasive particle removal
system 40 continuously removes abrasive particles from the catch
tank 42 without using mechanical agitators to suspend the abrasive
particles in the waste fluid.
[0022] The catch tank 42 preferably has a bottom panel 50, first
and second side-walls 51a and 51b projecting upward from opposing
sides of the bottom panel 50, and first and second end-walls 51c
and 51d projecting upward from opposing ends of the bottom panel
50. The first and second side-walls 51a and 51b are attached to the
first and second end-walls 51c and 51d to form a large cavity. The
catch tank 42 also includes a central divider 52 extending
longitudinally within the tank 42, and a plurality of crossing
dividers 54 extending transverse to the central divider 52. The
dividers 52 and 54 define a plurality of compartments 56
(identified by reference numbers 56a-56f) in the tank 42.
[0023] The compartments 56 receive the waste-fluid 12 and the
abrasive particles of the cutting-jet 28. Additionally, each
compartment 56 is configured to control the fluid flow within the
tank 42. For example, when the cutting-jet 28 is aligned with
compartment 56b, the dividers 52 and 54 defining this compartment
control the fluid flow such that the cutting-jet 28 alone suspends
a significant portion of the abrasive particles in the waste-fluid
12. As such, by dividing the tank 42 into smaller compartments 56,
the cutting-jet 28 maintains at least a substantial portion of the
abrasive particles in suspension in the waste-fluid 12 within a
particular compartment aligned with the cutting-jet 28 without
additional mechanical agitation. In general, each compartment is
approximately between 1'.times.1 and 4'.times.8', and more
preferably about 2'.times.4'. As explained in more detail below,
the fluid transport mechanism 44 continuously removes waste-fluid
12 and abrasive particles from the compartments 56.
[0024] FIG. 2 is a partial cross-sectional view of a portion of the
removal system 40 in which the fluid transport system includes a
number of conduit sections 60 (identified by reference numbers 60a
and 60b). The conduit sections 60 are configured in a serial
arrangement to transport waste fluid and abrasive particles to the
settling container 46 from the compartments 56a, 56b and 56c. The
conduit sections 60 include at least a first conduit section 60a
having a first end 62 positioned in the lower portion of
compartment 56b and a second end 64 positioned in compartment 56a.
The first conduit section 60a also has a first intake opening 66
proximate to the bottom panel 50, a second intake opening 68
located to receive a fluid flow from a conduit section from the
adjacent upstream compartment 56c, and a vent 67 toward the second
end 64. The second intake opening 68, for example, can be a funnel.
The conduit sections 60 can also include a second conduit section
60b similar to the first conduit section 60a, and thus like
reference numbers refer to like components. The second conduit
section 60a has a first end 62 positioned in the lower portion of
compartment 56a and a second end 64 coupled to the settling
container 46. The second intake opening 68 of the second conduit
section 60b is located to receive a first fluid flow F.sub.1 from
the second end 64 of the first conduit section 60a. Accordingly,
the first and second conduit sections 60a and 60b define a conduit
that transports waste fluid and abrasive particles from the
compartments 56a and 56b to the settling container 46.
[0025] To generate fluid flows through the conduit sections 60, a
fluid drive system 70 is preferably coupled to the conduit sections
60 to drive the waste-fluid 12 and the abrasive particles 14
through the conduit sections 60. In this particular embodiment, the
fluid drive system 70 includes a fluid driver 71, a primary line 72
coupled to the fluid driver 71, and a plurality of branch feed
lines 74 coupled to the primary line 72. The fluid driver 71 can be
a pressurized gas source, such as an air compressor. The primary
line 72 generally passes through the dividers 52 and 54 to supply
pressurized gas to all of the compartments 56. The branch feed
lines 74 are attached to the conduit sections 60 below the fluid
level of the waste-fluid 12 in the compartments 56. In operation,
the pressurized gas source 71 injects a gas 78, such as air, into
the conduit sections 60. The gas 78 accordingly rises through the
vertical portions of the conduit sections 60 drawing waste-fluid 12
and any abrasive particles 14 suspended in the waste-fluid 12
through the conduit sections 60. The gas 78 passes through the
vents 67, while the fluid continues to flow through the conduit
sections 60. The fluid drive mechanism 70, therefore, generates the
first fluid flow F.sub.1 through the first conduit section 60a and
a second fluid flow F.sub.2 through the second conduit section
60b.
[0026] The settling container 46 receives the second fluid flow
F.sub.2 from the second conduit section 60b. The settling container
46 can have a disposable drum 90 and a shroud 92 attached to a rim
of the drum 90. The shroud 92 has an inlet 94 coupled to the second
end 64 of the second conduit section 60b, and the shroud 92 has an
outlet 96 through which a clarified fluid 16 flows from the
settling container 46. As the second fluid flow F.sub.2 enters the
shroud inlet 94, the abrasive particles 14 fall downward and form
an abrasive particle accumulation 18 in the drum 90. The clarified
fluid 16 accordingly rises to the shroud outlet 96. The clarified
fluid 16 can then be pumped beck to the compartments 56 in the
catch tank 42 (shown schematically in FIG. 1), or it can overflow
the container 46 in flow into a drain.
[0027] Referring to FIGS. 1 and 2 together, the abrasive removal
system 40 removes abrasive particles from at least one of the
compartments 56 as the cutting-jet 28 moves along the cutting path
P. As the cutting-jet 28 passes over the compartment 56b, the
cutting-jet 28 agitates the waste-fluid 12 to suspend a significant
portion of the abrasive particles 14 within the compartment 56b
without additional mechanical agitation. The compartment 56b allows
the cutting-jet 28 to adequately suspend the abrasive particles 14
in the waste-fluid 12 without additional mechanical agitation
because the dividers 52 and 54 concentrate the turbulence generated
by the cutting-jet 28 and contain the abrasive particles 14 within
the relatively small volume of compartment 56b. The fluid flow
F.sub.1 through the first conduit section 60a accordingly draws a
portion of the waste-fluid 12 and the suspended abrasive particles
14 through the first conduit section 60a. The first fluid flow
F.sub.2 exits from the first conduit section 60a, and the second
fluid flow F.sub.2 in the second conduit section 60a draws the
first fluid flow F.sub.1 into the second intake opening 68 of the
second conduit section 60b. The suspended abrasive particles 14
from compartment 56b are thus transported to the settling container
46 through the first and second conduit sections 60a and 60b. The
clarified fluid 16 in the settling container 46 can then be
returned to the catch tank 42 to maintain a desired fluid level
within the tank 42, or the clarified fluid 16 can be disposed of in
an environmentally safe manner.
[0028] One aspect of the cutting machine 10 is that it reduces the
down-time to remove abrasive particles from the catch tank 42
compared to many conventional removal systems. The abrasive
particle removal system 40 continuously removes abrasive particles
from the catch tank 42 without using additional mechanical
agitators to suspend the abrasive particles 14 in the waste fluid
12. By continuously removing the abrasive particles from the catch
tank 42, the cutting machine 10 does not need to be shut down for
cleaning the catch tank 42. Thus, compared to conventional removal
techniques that shut down the cutting machines to allow the
abrasive particles to settle, the abrasive particle removal system
40 reduces the down-time of the cutting machine 10.
[0029] Additionally, another aspect of the cutting machine 10 is
that it is generally less expensive to manufacture and operate than
conventional cutting machines with centrifugal abrasive removal
systems. As set forth above, conventional centrifugal abrasive
systems use large, expensive pumps to suspend the abrasive
particles in large catch tanks. The abrasive particle removal
system 40, however, divides the catch tank 42 into a plurality of
smaller compartments 56 that control the fluid flow within the
catch tank 42 so that the cutting-jet 28 suspends the abrasive
particles in an active compartment 56 without additional mechanical
agitation. The abrasive particle removal system 40 can accordingly
use inexpensive, low volume fluid drive systems instead of the
large, expensive pumps. Thus, the abrasive particle removal system
40 is less expensive to manufacture and operate than large capacity
centrifugal abrasive removal systems.
[0030] Still another aspect of the abrasive particle removal system
40 is that it is reliable and does not require a significant amount
of maintenance. The removal system 40 has very few moving
components, and none of the moving components directly contact the
abrasive particles. In contrast to the removal system 40, the
conventional conveyor rake and centrifugal removal systems have
several moving parts that directly contact the abrasive particles.
As such, the abrasive particles can wear down many important
components of conventional removal systems (e.g., conveyor rakes,
pumps and centrifugal separators). Thus, because the removal system
40 has very few moving parts, it is a reliable system that does not
require a significant amount of down-time for maintenance.
[0031] FIG. 3 is a partial cross-sectional view of another
embodiment of an abrasive particle removal system 140. The abrasive
particle removal system 140 illustrated in FIG. 3 is similar to the
removal system 40 illustrated in FIG. 2, and thus like reference
numbers refer to like components. Referring to FIG. 3, a first
conduit section 160a has a first end 162 positioned in a lower
portion of compartment 56b and a second end 164 positioned in
compartment 56a. Additionally, a second conduit section 160b has a
first end 162 positioned in compartment 56a and a second end 164
coupled to the shroud inlet 94. Each conduit section 160a and 160b
has a back-flush valve 69 to control the fluid flows through the
conduit sections. Unlike the removal system 40 of FIG. 2, the first
ends 162 of the conduit sections 160 have a single intake opening
166. In operation, therefore, the gas 78 from the pressurized gas
source 71 rises through the conduit sections 160a and 160b to
generate the first and second flows F.sub.1 and F.sub.2.
[0032] FIG. 3 also illustrates the operation of the back-flush
valves 69 in the conduit sections. For example, the abrasive
particles in the first flow F.sub.1 may accumulate in an abrasive
particle accumulation 118 in compartment 56a at the first end 162
of the second conduit section 160b. The abrasive particle
accumulation 118 in compartment 56a may eventually block the intake
opening 166 of the second conduit section 160b. To clear the intake
opening 166 in compartment 56a, the back-flush valve 69 in the
second conduit section 56b is closed. The pressure in the second
conduit section 160b upstream from the back-flush valve 69 builds
until it blows backward through the intake opening 166. The
pressurized gas source 71 accordingly should operate at 70-150 psi
to provide sufficient pressure to blow abrasive particle
accumulations away from the first end 162 of the second conduit
section 160b.
[0033] FIG. 4 is a partial cross-sectional view of still another
embodiment of an abrasive particle removal system. The abrasive
particle removal system 240 has conduit sections 260 (identified by
reference numbers 260a and 260b) with first ends 62 coupled
directly to the primary line 72 of the fluid drive system 70. As
such, the gas 78 rises through the vertical portions of the conduit
sections 260 to draw the fluid through the first and second intake
openings 66 and 68. Additionally, a second back-flush valve 79 may
be positioned in the primary line 72 after the connection of each
conduit section 260. To clear a first conduit section 260a, for
example, the back-flush valve 69 in the first conduit section 260a
and the back-flush valve 79 in compartment 56b are closed to allow
pressure to build within the first conduit section 260a.
[0034] FIG. 5 is a partial cross-sectional view illustrating
another abrasive removal system 340 having a conduit 360 with a
main conduit section 361 and a plurality of compartment conduit
sections 363 (indicated by reference numbers 363a and 363b). For
example, a first conduit section 363a has a first end 362 in the
lower portion of compartment 56b and a second end 364 attached to
the main conduit section 361. Similarly, a second conduit section
363b has a first end 362 in the lower portion of compartment 56a
and a second end 364 coupled to the main conduit section 361. In
operation, therefore, the fluid drive system 70 draws fluid through
the compartment conduit sections 363 and into the main conduit
section 361 such that a final fluid flow F.sub.f flows through the
shroud inlet 94.
[0035] FIG. 6 is a partial cross-sectional view illustrating still
another abrasive removal system 440 in which the conduit sections
440 (identified by reference numbers 440a and 440b) operate in
parallel to individually deliver separate fluid flows F.sub.1 and
F.sub.2 into the settling container 46. In this embodiment, a first
fluid section 440a has a first end 442a positioned in a lower
portion of compartment 56b and a second end 444a coupled to the
shroud inlet 94. A second conduit section 440b has a first end 442b
positioned in compartment 56a and a second end 444b also coupled to
the shroud inlet 94. Thus, in this embodiment, a number of parallel
fluid flows are delivered to the settling container 46.
[0036] FIG. 7 is a schematic isometric view of another abrasive
particle removal system 540 for use with the cutting machine 10.
The removal system 540 has a catch tank 542 with a longitudinal
divider 552 extending longitudinally along the tank 542 and a
number of crossing dividers 554 extending transverse to the
longitudinal divider 552. The sidewalls 551 project upward from a
bottom panel 550 to an elevation above the top edges of the
dividers 552 and 554 such that the level of the waste-fluid 12 can
be above the top edges of the dividers. The dividers 552 and 554
may thus be baffles that define a plurality of compartments 556
(identified individually by reference numbers 556a-556f) that
restrict the fluid flow from one compartment to another, but still
allow the fluid to flow over the baffles.
[0037] From the foregoing it will be appreciated that, although
specific embodiments of the invention have been described herein
for purposes of illustration, various modifications may be made
without deviating from the spirit and scope of the invention. For
example, the fluid driver 71 of the fluid drive system 70 can be a
pump or an impeller instead of a pressurized gas source to drive a
fluid through the primary line 72 and feed lines 74. Additionally,
the removal systems could also be used to remove other solids from
a catch tank generated by abrasive or non-abrasive cleaning and/or
cutting operations. Such additional applications may be separating
paint chips, dirt and other solids from a catch tank in ship
cleaning, building cleaning and many other cleaning applications.
Accordingly, the invention is not limited except as by the appended
claims.
* * * * *