U.S. patent application number 10/639764 was filed with the patent office on 2004-07-08 for fluid jet cutting system.
Invention is credited to Fuentes, Roland, Kelley, Jerry, Langford, Mark A., Presson, Earl W., Segewitz, Manfred, Walker, Ronald L..
Application Number | 20040132383 10/639764 |
Document ID | / |
Family ID | 32686008 |
Filed Date | 2004-07-08 |
United States Patent
Application |
20040132383 |
Kind Code |
A1 |
Langford, Mark A. ; et
al. |
July 8, 2004 |
Fluid jet cutting system
Abstract
A method and apparatus for preventing water from entering the
abrasive port of an entrained high pressure fluid jet nozzle and a
method and apparatus for attaching the high pressure fluid jet
nozzle to a hazardous duty robot. The invention includes the
application of a positive air pressure to an abrasive line
preferably during those times when there is insufficient vacuum
generate by high pressure fluid being sent through the restricted
orifice in the high pressure nozzle. The invention prevents
clogging of a fluid jet cutting system during operation. The
invention includes mounting a nozzle and/or visualization system to
an expandable and contactable component such as a grasping device
that allows for continued use of the expandable and contractible
grasping unit. This includes, for example, a grasping device that
is provided out the end of a movable robot arm and that allows for
rotation of the grasping device.
Inventors: |
Langford, Mark A.; (Harvest,
AL) ; Fuentes, Roland; (Owens Cross Roads, AL)
; Kelley, Jerry; (Decatur, AL) ; Walker, Ronald
L.; (Falkville, AL) ; Segewitz, Manfred;
(Huntsville, AL) ; Presson, Earl W.; (Brownsboro,
AL) |
Correspondence
Address: |
SMITH, GAMBRELL & RUSSELL, LLP
SUITE 800
1850 M STREET, N.W.
WASHINGTON
DC
20036
US
|
Family ID: |
32686008 |
Appl. No.: |
10/639764 |
Filed: |
August 13, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60402906 |
Aug 14, 2002 |
|
|
|
60480223 |
Jun 23, 2003 |
|
|
|
Current U.S.
Class: |
451/38 ; 451/91;
451/99 |
Current CPC
Class: |
B24C 1/045 20130101;
B24C 7/0007 20130101; B24C 3/06 20130101 |
Class at
Publication: |
451/038 ;
451/091; 451/099 |
International
Class: |
B24B 001/00; B24C
001/00; B24C 005/00 |
Claims
What is claimed is:
1. A fluid jet cutting system, comprising: a nozzle; a fluid
communication line in fluid communication with said nozzle; an
abrasive feed line in communication with said nozzle; and an
abrasive purge gas line which is arranged so as to avoid fluid
entry into the abrasive line.
2. The fluid jet cutting system as recited in claim 1 further
comprising a hazardous duty robot and with a nozzle mount on which
said nozzle is supported.
3. The fluid jet cutting system as recited in claim 2 further
comprising an abrasive hopper mount assembly comprising an abrasive
supply container and an abrasive supply container robot mount.
4. The fluid jet cutting system as recited in claim 3 further
comprising a pressurizable enclosure which is positioned for
providing pressurized purge gas to the abrasive feed line and is
supported on said robot.
5. The fluid jet cutting system as recited in claim 4 further
comprising a pressurized gas source in communication with said
pressurizable enclosure to pressurize said container when
operating.
6. The fluid jet cutting system as recited in claim 1 further
comprising an abrasive hopper and an adjustable stop which is
positioned between an output location of said hopper and an
abrasive in feed location for said abrasive feed line feeding into
said nozzle.
7. The fluid jet cutting system as recited in claim 4 wherein said
pressurizable enclosure includes a vacuum sensor.
8. The fluid jet cutting system as recited in claim 7 wherein said
vacuum sensor includes a seal member which moves into a first
position which unseals said enclosure upon a predetermined vacuum
level being present and moves into a seal enclosure position when
there is present a more pressurized state than said vacuum
level.
9. The fluid jet cutting system as recited in claim 8 wherein said
seal is a flap seal positioned relative to said enclosure so as to
flap open upon said predetermined vacuum level being present in the
enclosure and flap shut when a higher pressure environment level is
reached in the enclosure.
10. The fluid jet cutting system as recited in claim 1 further
comprising purge gas line access means that is positioned in said
abrasive line.
11. The fluid jet cutting system as recited in claim 10 wherein
said purge gas line access means is a fitting that has a gas
reception component and abrasive flow component with the abrasive
flow component provided in-line with said abrasive line and said
branch component being in communication with a purge gas
source.
12. The fluid jet cutting system as recited in claim 1 further
comprising an abrasive hopper and a manifold with said abrasive
hopper supported on said manifold and said abrasive hopper feeding
through said manifold and into said abrasive feed line, and said
manifold supporting a pressurizable enclosure which is in
communication with said abrasive feed line.
13. The fluid jet cutting system as recited in claim 11 wherein
said fitting is positioned closer to an inlet location for abrasive
in said abrasive line than to an outlet opening into said
nozzle.
14. The fluid jet cutting system as recited in claim 1 further
comprising an abrasive hopper and an adjustable stop which is
positioned between an output location of said hopper and an in feed
location for said abrasive feed line feeding into said nozzle and
an air driven driver for adjusting said stop to different flow
through settings.
15. The fluid jet cutting system as recited in claim 1 further
comprising a hazardous duty robot with a nozzle mount on which said
nozzle is supported, and said nozzle mount including a grasping
member and a mounting assembly which is secured to an exterior
section of said grasping member.
16. The fluid jet cutting system as recited in claim 15 wherein
said grasping member includes a multi-prong assembly with said
prongs being supported in a fashion providing for expansion and
contraction and said nozzle being mounted on one of said
prongs.
17. The fluid jet cutting system as recited in claim 16 further
comprising control means for adjusting said prongs to different
radial locations and initiating and discontinuing fluid jet cutting
flow at different radial locations of said nozzle.
18. The fluid jet cutting system as recited in claim 16 comprising
rotating said grasping arm for greater than 360 degrees to repeat a
cut over of a portion of a previously impacted cut path.
19. The fluid jet cutting system as recited in claim 1 further
comprising a nozzle mount which orientates, during operation of
said fluid jet cutting system, said nozzle at other than a vertical
orientation.
20. The fluid jet cutting system as recited in claim 19 wherein
other than a vertical orientation includes an orientation more
horizontal than vertical.
21. The fluid jet cutting system as recited in claim 1 wherein said
purge line has a pressure level of 10 to 20 psi.
22. The fluid jet cutting system as recited in claim 1 wherein said
nozzle is supported on a movable support.
23. The fluid jet cutting system as recited in claim 22 wherein
said movable support includes an autonomous or remotely operated
hazardous duty robot with a manipulation arm on which said nozzle
is supported.
24. The fluid jet cutting system as recited in claim 23 further
comprising a grasping device supported by said arm and attached to
an outer portion of said grasping device so as to enable continued
use of said grasping device for grasping functions.
25. A fluid jet cutting system, comprising: a nozzle; a fluid
communication line in fluid communication with said nozzle; an
abrasive feed line in communication with said nozzle; and means for
preventing fluid entry into the abrasive communication line at
times when a sufficient vacuum level has not been generated by
fluid flow exiting said nozzle.
26. The fluid jet cutting system as recited in claim 25 further
comprising a nozzle mount which orientates, during operation of
said fluid jet cutting system, said nozzle at other than a vertical
orientation.
27. The fluid jet cutting system as recited in claim 26 wherein
other than a vertical orientation includes an orientation more
horizontal than vertical.
28. The fluid jet cutting system as recited in claim 25 wherein
said nozzle is supported on a movable support.
29. The fluid jet cutting system as recited in claim 28 wherein
said movable support includes an autonomous or remotely operated
hazardous duty robot with a manipulation arm on which said nozzle
is supported.
30. The fluid jet cutting system as recited in claim 29 further
comprising a grasping unit supported by said arm and said nozzle
being attached to an outer portion of said grasping unit so as to
enable continued use of said grasping unit for grasping
functions.
31. A fluid jet cutting system, comprising: a nozzle; a fluid
communication line in fluid communication with said nozzle; an
abrasive feed line in communication with said nozzle; and a movable
support supporting said nozzle, said movable support including a
grasping device and said grasping device supporting said nozzle at
a location which provides for continued use of said grasper.
32. The fluid jet cutting system as recited in claim 31 wherein
said grasping device includes expandable and collapsible prongs and
said nozzle is supported on an outer portion of one of said
prongs.
33. The fluid jet cutting system as recited in claim 32 wherein
said movable support further comprises an autonomous or remote
hazardous duty robot which supports said grasping device.
34. The fluid jet cutting system as recited in claim 33 wherein
said robot includes an adjustable arm on which is mounted said
grasping device.
35. The fluid jet cutting system as recited in claim 31 wherein
said grasping device is rotatable around a pivot axis of said
grasping device, and said nozzle has an outlet axis that rotates
about said pivot axis at a distance defined by a spacing of said
nozzle outward of said pivot axis.
36. The fluid jet cutting system as recited in claim 35 further
comprising control means for adjusting said prongs to different
radial locations and initiating and discontinuing fluid jet cutting
flow at different settings of said different radial locations.
37. The fluid jet cutting system as recited in claim 36 wherein
said prong adjustment and cutting fluid activation and deactivation
is preprogrammed into said control means.
38. A fluid jet cutting system as recited in claim 1 including
means for timing on/off states of fluid supply in said fluid
communication line, abrasive flow in said abrasive feed line, and
gas supply in said purge line which includes a delay in supply of
abrasive until sufficient time has passed for vacuum generation by
said fluid flow in said nozzle.
39. A fluid jet cutting system as recited in claim 1 including
means for timing on/off states of fluid supply in said fluid
communication line, abrasive flow in said abrasive feed line, and
gas supply in said purge line which includes a shut down sequence
of shutting off abrasive flow, subsequently shutting off purge air
flow and then subsequently shutting off fluid flow to said
nozzle.
40. A method of preventing a wetting of abrasive in an abrasive
feed line leading to and opening into a nozzle in a fluid jet
cutting system, comprising providing a pressurized gas state in
said abrasive feed line which precludes liquid in-flow into said
abrasive feed line.
41. A method of manipulating a nozzle in a fluid jet cutting
system, comprising providing a nozzle on a grasping unit with
expandable and retractable components which nozzle is positioned on
an outer portion of said expandable and retractable components, and
adjusting said components to achieve different radial locations in
said nozzle and initiating and discontinuing fluid jet cutting flow
at different radial locations.
42. A fluid jet cutting system comprising: a fluid jet nozzle which
includes an inlet for fluid and an inlet for abrasive; a
visualization system; a multi-prong grasping assembly having a
first and a second prong and means for adjusting the relative
position of said prongs, and said visualization system supported on
a first of said prongs and said nozzle on a second of said
prongs.
43. The fluid jet cutting system as recited in claim 41 wherein
said visualization system is supported on an external side of said
first prong and said nozzle on an external side of said second
prong such that said prongs are placeable in a grasping state
relative to an object positioned between said objects.
Description
[0001] This application claims priority under 35 U.S.C. .sctn.
119(e) to Provisional Application 60/402,906 filed Aug. 14, 2002
and Provisional Application 60/480,223 filed Jun. 23, 2003, with
each being incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention pertains to a fluid jet cutting system
that includes an apparatus and method for preventing fluid from
getting into the abrasive line feeding a high pressure fluid jet
nozzle, and a method and apparatus for facilitating operation of
system components including, for example, system components such as
a high pressure fluid jet nozzle and/or visualization assembly
supported by a movable member, as in a hazardous duty robot
manipulator arm, with control means provided for manipulating the
supported components. The present invention also includes means for
providing remote abrasive flow control to a preferred in-situ
abrasive source.
BACKGROUND OF THE INVENTION
[0003] Conventional fluid jet cutting systems are designed with a
vertically mounted nozzle and the fluid jet cutting stream directed
vertically downward for impacting a work piece such as a flat plate
being cut. When liquid is flowing, a vacuum is set up by the
venturi effect at the abrasive inlet and abrasive is drawn into the
liquid (e.g., water) stream. When the water is turned off and the
abrasive supply is turned off, the vacuum at the abrasive port
disappears and the nozzle stops spraying high pressure water and
abrasive mixture. Even when the nozzle is off, water dribbles out
of the nozzle due to the forces of gravity. Because, however, the
nozzle is vertical in these prior art systems, water does not
easily enter into the abrasive line and it stays relatively dry and
not readily clogged.
[0004] U.S. Publication 20020112598, which published on Aug. 22,
2002 and is assigned to Teledyne Brown Engineering, Inc. of
Hunstville, Ala., relates to a method for remotely accessing
packages containing hazardous devices using a stream of high
velocity abrasive particles and/or fluid(s). The stream is created
in-situ while attached to a remotely or autonomously operated
vehicle. The focusing of the high velocity abrasive particle
solution onto the exterior surface of the hazardous device is
achieved at a controlled speed and impact area which is below the
impact initiation threshold of the hazardous device.
[0005] In fluid jet cutting operations such as those used in the
above described remote hazardous interdiction, the nozzle is
mounted on a hazardous duty robot or as a hand held apparatus, and
is typically mounted or held such that the nozzle is more
horizontal than vertical. When the high pressure fluid (e.g.,
water) is turned off, the water dribbles out of the nozzle and also
enters the abrasive line by the action of gravity. Water can also
be introduced to the abrasive line when the high pressure water
supply is initially turned "ON". Once the operator takes action to
turn "ON" the high pressure water, there is a time delay associated
with the water pressure rising from 0 psi to the operating pressure
(e.g., 50,000 psi). During the transition time, water can enter
into the abrasive line until the water pressure is developed to the
point that a vacuum is established at the vacuum port. This
phenomena is represented by the lower curve (H1) in FIG. 2. Note
that from time 1.0 seconds after turn "ON" to 1.8 seconds after
turn "ON", the water in the nozzle actually results in a positive
pressure in the abrasive line during this time. Once the high
pressure water stream is sufficiently established, a vacuum is
established at the abrasive port that results from the venturi
action of the water stream. This is depicted by the lower curve
(H1) in FIG. 2 which shows, when the time approximately equals 2
seconds, the pressure at the abrasive port transitions to negative
(i.e., vacuum). In practice, the resulting vacuum at the abrasive
port does not pull all of the water from the line previously
introduced during the positive pressure stage. The presence of
water in the abrasive line leads to clogging of the abrasive line
when abrasive is introduced to the wet abrasive line. This clogging
prevents the proper operation of such a system. Therefore, there is
a need for a method and apparatus for preventing water from
entering the abrasive line of a fluid jet nozzle (an entrained high
pressure fluid jet nozzle) in a fluid jet cutting system that
prevents the clogging of the system, with this need being
particularly high for supported nozzles where the orientation of
the nozzle can facilitate fluid entry into the abrasive line such
as hazardous duty robot supported nozzles that can assume
non-vertical orientation.
[0006] In fluid jet cutting operations such as those involving
hazardous duty robots there is also difficulty in maintaining
proper positioning of the nozzle and for visualizing the cutting
area and surrounding area prior to, during and after a cutting
sequence is performed. There is also a need for improvements in
mounting the nozzle and preferably other system components (e.g.,
visualization system) at a high operational efficiency location
while avoiding interfering with other preferred functions of a
hazardous duty robot as in grasping operations by a grasping
mechanism of the robot. This includes, for example, camera and
light visualization means associated with the fluid nozzle and
positioned to provide a clear view while keeping components
protected from the harsh environment associated with a high
pressure fluid/abrasive mix output. There is also a need to provide
protection means to susceptible components such as the manipulator
arm extension mechanism to avoid abrasive accumulation and system
degradation. There is also a need for improvements in
simplifying/speeding up operational procedure in the application of
the fluid jet cutting stream, particularly when dealing with
potentially hazardous situations as in car bomb interdiction.
SUMMARY OF THE INVENTION
[0007] The present invention includes a method and apparatus
directed at addressing the aforementioned problems and addressing
the noted areas in need of improvement. In one embodiment of the
invention there is provided a system for preventing fluid jet
cutting nozzle liquid (e.g., water) from entering the abrasive line
of the fluid jet cutting system such as through an application of a
positive pressure to the abrasive line during periods where the
abrasive line is susceptible to clogging. For example, providing
positive pressure purge gas during those times (or time periods)
when abrasive is not flowing through the nozzle or the abrasive
line (e.g., during the time the abrasive supply command is off) or
during predetermined periods within a period the abrasive feed is
off (e.g., for a specified period before start up) and/or during
times when there is insufficient vacuum flow generated to create a
sufficient vacuum flow in the abrasive feed line to preclude
abrasive line wetting (e.g., following system activation but before
a sufficient vacuum level is generated by the high pressure liquid
passing through the nozzle's restricted region). This positive
pressure is preferably provided by way of fluid pressure (e.g., a
gas such as air or some other non-clump forming fluid) which
prevents cutting fluid (usually a liquid such as water) from
entering the abrasive port outlet and/or line leading thereto. For
convenience, "air" will be used relative to the purge fluid and
"water" relative to the cutting liquid, hereafter, although it is
to be understood the present invention is not limited to these
types of fluids in their respective uses. The positive air pressure
forces the water that drains from the water line or remains in the
nozzle area to exit the system through the nozzle. In this manner
the abrasive line remains dry and clog free.
[0008] Referring to FIG. 2, the upper line (H2) illustrates how
pressurizing the abrasive port with air during the time that high
pressure water is not flowing through the nozzle prevents water
from entering the abrasive port regardless of the orientation of
the nozzle. While it is preferred that the purge air flow be off
when abrasive is flowing, the purge air can also be maintained
during abrasive flow, as the purge air pressure level is relatively
low and at a flat rate and thus does not significantly interfere
with the abrasive flow in the system when the abrasive is pulled by
the vacuum effect produced by the liquid. Also, because of the
preferred close proximity of the abrasive hopper source to the
nozzle (e.g., less than 120 inches), there is not needed a separate
pressure delivery system for the abrasive feed. If a pressure
delivery system is used to deliver the abrasive, the purge air line
is preferably closed off during the pressurized delivery system
operation to avoid a situation where a higher pressurized abrasive
delivery system pushes abrasive into a purge air source operating
at a lower pressure. This activity is preferably controlled by a
processor associated with the fluid cutting system which shuts down
and precludes operation of the purge gas system when the
pressurized abrasive delivery system is in operation.
[0009] In one embodiment of the invention, an air introduction
facilitation means, such as a `Y-fitting` (or T-fitting) is
installed in the abrasive line between the fluid jet nozzle outlet
port and the abrasive supply container (e.g., between the abrasive
feed line outlet port in the nozzle and an abrasive container
hopper outlet feeding into an inlet region of the abrasive feed
line). This structure forces air (e.g., all or a portion that is
taken in at an intake source) to exit through the nozzle and
prevents water from flowing into the abrasive inlet nozzle port and
clogging the fluid jet cutting system.
[0010] In another embodiment of the invention, positive air
pressure is provided through use of a sealed enclosure that is
preferably positioned in the region of the bottom of an abrasive
hopper and encompasses the exchange region between the abrasive
hopper or container and the inlet region of the abrasive feed line.
With this arrangement, pressurized air in the enclosure is directed
to exit the fluid jet cutting nozzle and the abrasive hopper or
through the nozzle alone such as with air flow blocking means
(e.g., a pinch valve precluding flow in the abrasive line other
than to the outlet of the nozzle). The air exiting through the
nozzle prevents water from entering the abrasive line Air flowing
into the hopper container through the hopper outlet for feeding
abrasive when in an abrasive flow mode helps percolate the abrasive
and break up clumping in the hopper and elsewhere between abrasive
flow modes.
[0011] The present invention also features a fluid jet cutting
system with nozzle mounting means that is associated with a
grasping device on a movable member as in a robot (e.g., a remote
and/or autonomously operated hazardous duty robot). In a preferred
embodiment, the fluid jet cutting nozzle is mounted on one prong of
a multi-prong grasping unit of the robot and robot operation
control means provides for grasping unit manipulation: both for
grasping units when in a grasping mode and positioning and movement
of the fluid jet cutting nozzle stream during a cutting operation,
or both (e g., simultaneous cutting and grasping operations-as in
an unscrewing operation with simultaneous circular cutting). The
present invention's nozzle grasping arrangement also facilitates
sequenced cutting such as through multiple layers and/or repeated
path travel cutting by, for example, repeated rotation of the
grasping unit while at a certain radius setting to speed up the
cutting process and ensure a complete cut through. There is also
preferably further provided visualization means with a preferred
location being one on the multi-prong grasping unit such as on the
exterior of a second grasping prong of the multi-prong grasping
unit adjacent a first prong supporting the nozzle. As an example,
the present invention includes a visualization device (e.g., camera
or video feed) and light source mount which displays and
illuminates the area being subjected to the fluid abrasive impact
and which includes protection means for protecting the
visualization device and the light source from abrasive
contact.
[0012] The present invention also features an adjustable abrasive
flow control that is preferably air pressure activated (between
full closed to full open or with set points added between those
modes) via a control pressure line that preferably derives air
pressure from a common source as that feeding the abrasive purge
line and whose activation is also preferably controllable by the
control means of the fluid cutting system. When using the
adjustable flow control for full open and full closed modes only,
there is preferably further provided adjustable abrasive flow
control level setting means for setting, preferably manually
between uses, a desired abrasive flow opening setting. For example,
a setting screw is provided in one embodiment to present the
opening size when the abrasive flow stopper is in its fully open
mode (e.g., a setting screw which sets the stop to allow, for
example, for 1/2 full open aperture sizing when the stop is in its
maximum open state. Alternate embodiments include automated
adjustable setting means which can adjust, preferably in real time
and via a remote controller, the abrasive flow control level
between either full aperture open or full aperture closed settings
or set points of three or more in number between maximum open and
full shut.
[0013] An embodiment of the present invention includes a fluid jet
cutting system, comprising a nozzle with a fluid communication line
in fluid communication with the nozzle, an abrasive feed line also
in communication with the nozzle, and a purge gas supply means as
in an air supply line which is arranged so as to avoid cutting
fluid (e.g., water) entry into the abrasive port and line leading
thereto. Also, the fluid jet cutting system also preferably
comprises a hazardous duty robot which represents one form of a
movable support having a nozzle mount on which the nozzle is
supported. In a preferred embodiment there is further included an
abrasive hopper mount assembly comprising an abrasive supply
container and an abrasive supply container robot mount.
[0014] An embodiment of the invention features a pressurizable
enclosure which is positioned for providing pressurized purge air
to the abrasive feed line to prevent fluid entry of liquid into the
port of the abrasive outlet and clumping of the abrasive in the
system. The pressurizable enclosure is pressurized via a
pressurizing or pressurized gas source in communication with the
enclosure such as an air compressor (the gas source being mounted
on the robot or located independently at a separate location as in
a storage vehicle on which the robot is transported to a desired
site and in air feed communication via an air feed line to the
robot) that is preferably stepped down (e.g., 120 psi down to 15
psi) via a regulator which is preferably robot supported. The
abrasive line pressure level is from 10 to 20 psi in one embodiment
and is adjusted to provide sufficient gas flow to pressurize the
line to an extent which precludes fluid entry. An autonomous or
remotely operated robot is preferred, although the above described
nozzle mounting means and air purge system are utilizable on fixed
foundation devices (e.g., a fixed foundation having a manipulator
arm with grasping device or other types of movable supports
extending from a fixed foundation or free of movement, or an
entirely stationary fluid jet cutting devices).
[0015] An embodiment of the invention features a vacuum sensor as
in a combination vacuum seal/vacuum sensor associated with, for
example, the pressurizable enclosure so as to depressurize the
enclosure when a vacuum setting is determined (e.g., sufficient
vacuum draw from the venturi fluid flow in the nozzle) and seals
off the enclosure when a sufficient vacuum in the system is not
sensed. In a preferred embodiment the vacuum sensor includes a seal
member that is mounted on, for example, an interior portion (e.g.,
side wall) of the enclosure about a port in the same and which
moves into a first position which unseals the enclosure upon a
vacuum level being present in the nozzle and moves into a seal
enclosure position when there exists a more pressurized state than
the predetermined vacuum level. As an example of a suitable vacuum
sensing means there is featured a flap seal supported by said
enclosure so as to flap open upon a vacuum level being present in
the enclosure (as by way of a vacuum effect of the fluid flowing,
for example, at a higher pressure level such as 50,000 psi through
the nozzle and the vacuum draw induced thereby on the abrasive feed
line extending into communication with the enclosure). The flap
also shuts and seals the enclosure when a higher pressure
environment level is reached in the enclosure. Other automatic
sensor valves such as a floating ball valve are also featured under
the present invention, but the flap valve represents a highly
reliable, preferred embodiment. Additional alternatives include,
for example, electronically activated valve devices associated with
sensors (e.g., a vacuum sensor monitoring the nozzle's constricted
orifice port), but the flap device avoids the added complexity
associated with such electronic controls.
[0016] An alternate embodiment of the fluid jet cutting system
includes a purge gas line access means that is positioned in the
abrasive line such as a fitting (e.g., a Y or T fitting) that has a
gas reception component and an abrasive flow component, with the
abrasive flow component provided in line with or as an integral
part of the abrasive line and with the branch component being in
communication with a purge gas source. The fitting can be placed at
multiple locations as, for example, a location closer to an inlet
location for the abrasive feed into said abrasive line than to an
abrasive outlet port opening into said nozzle, or is
associated/fitted with the nozzle or along a flexible communication
line (e.g., a transparent abrasive flexible feed conduit forming a
component of the abrasive feed line) extending therebetween. The
pressure level of the purge gas in the system for maintaining
liquid from entering the abrasive outlet port (to be interpreted as
being a part of the "abrasive line") and avoiding abrasive clumping
in the abrasive line is preferably from 10 to 20 psi. The present
invention thus features a plurality of different embodiments
providing means for preventing fluid entry into the abrasive
communication line such as at times when a sufficient vacuum level
has not been generated by fluid flow exiting said nozzle, and, as
noted above, preferably also when the abrasive flow has been shut
off (e.g., abrasive flow shut off as a preferred prerequisite
before the abrasive purge gas flow is turned on with the liquid
flow preferably being shut off after a delayed period following
both abrasive flow shut off and subsequent purge air turn on to
help in clearing line of abrasive before the next abrasive flow
turn on (with the control means preferably monitoring the enabling
functions and/or instructing an automated sequence of events); and
on the start up side, the fluid is preferably turned on first, then
followed by the purge air at a preset period of time and then
followed by the abrasive flow start up after another preset period
of time (again with the control means either automatically
sequencing and/or controlling the enabling functions in an operator
generated sequence).
[0017] An embodiment of the invention further comprises a hazardous
duty robot with a nozzle mount on which the nozzle is supported,
and the nozzle mount including a grasping member and a mounting
assembly which is secured to an exterior section of the grasping
member such as a grasping member that includes a multi-prong
assembly with the prongs being supported in a fashion providing for
expansion and contraction, and the nozzle being mounted on an
exterior portion of one of the prongs. The grasping member is also
preferably in communication with control means for adjusting the
prongs to different radial locations and initiating and
discontinuing fluid jet cutting flow at different radial locations
of the nozzle. The control means is preferably a stand alone system
with sub-control systems for controlling air flow, hydraulic flow
(as in the intensifier), and liquid flow to the nozzle and can be a
stand alone or interfaced with the control means on the robot which
controls operations such as rotating the grasping arm for greater
than 360 degrees which provides for a repeat of a cutting operation
over the same portion of a previously impacted cut path. For
example, the control means for controlling air and liquid flow can
interface with the control means for manipulating the position of
the robot's components as in the manipulator arm via a robot
interface unit so as to automate both the positioning and flow of
fluid relative to an object being treated.
[0018] The fluid jet cutting system also preferably comprises a
nozzle mount which orientates, during operation of the fluid jet
cutting system, the nozzle at other than a vertical orientation as
in an orientation that includes an orientation more horizontal than
vertical. This can be achieved on the hazardous duty robot by
controller manipulation of a manipulation arm on which the nozzle
is supported and/or a grasping unit supported on that arm. An
embodiment of the invention further comprises a nozzle mount
assembly that mounts the fluid jet cutting nozzle on the grasping
means in a fashion that enables continued use of the grasping means
for grasping functions and/or use of the nozzle in a cutting
operation. A preferred embodiment of the present invention also
includes a visualization device and/or light source support device
with means for protecting each as well as means for mounting one or
both on an opposite prong of the grasping device or on a different
location as in a supporting base area of a fixed robot.
[0019] The present invention also features a high pressure hose
guiding means that provides for adjustment of the nozzle and high
pressure hose section extending from initial robot contact to the
nozzle fixation point while maintaining the hose in a minimized
length state between the guide means contact and the nozzle
fixation point (as in a straight line or a single curve
configuration extension between these points). The hose guide means
preferably is in the form of a confining roller assembly that is
used to help control and guide the high pressure hose. The guide
means thus helps keep the hose away from the tracks or wheels of a
movable support as in a robot and also takes and alleviates the
force of dragging the hose while driving the robot to its
destination. It thus also prevents the robot arm from being
subjected to the full extent of the drag load of the hose in
contact with the ground or caught up on an object as in the crevice
of an automobile tire.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The various advantages of the present invention will become
apparent to one skilled in the art by reading the following
specification and subjoined claims and by referencing the following
drawings in which:
[0021] FIG. 1 is a perspective view of a fluid jet nozzle and air
purged abrasive feed system;
[0022] FIG. 1A illustrates an alternate embodiment of an abrasive
line air purge system;
[0023] FIG. 2 is a graph of abrasive port transitional pressure
versus time data;
[0024] FIG. 3 shows a rear elevational view of a preferred hopper
mount assembly (with rear being that which is farthest removed from
the object being subjected to the fluid cutting system);
[0025] FIG. 4 shows a first side elevational view of that the
hopper mount assembly shown in FIG. 3;
[0026] FIG. 5 is a perspective view of the abrasive hopper mount
assembly;
[0027] FIG. 6 shows a similar view as in FIG. 5 but with a
transparent empty abrasive hopper and an illustration of the bottom
conical abrasive feed out port;
[0028] FIG. 7 is a front view of the hopper mount assembly;
[0029] FIG. 8 is an opposite side view of that which is shown in
FIG. 4;
[0030] FIG. 9 shows a partial view of the hopper mount assembly
mounted on a hazardous duty robot;
[0031] FIG. 10 shows a cross-sectional view of the outlet portion
of the hopper mount assembly;
[0032] FIG. 11 shows an exploded view of the nozzle mounting
assembly of the present invention featuring a cutting nozzle,
grasping prong and nozzle mount;
[0033] FIG. 12 shows the nozzle mounting assembly in an assembled
state;
[0034] FIG. 13 shows an illustration of a preferred embodiment of a
fluid jet cutting system with a hazardous duty robot with mounted
hopper mount assembly and nozzle mounting assembly illustrated;
[0035] FIG. 14 shows a more detailed view of the front end of that
which is shown in FIG. 13.
[0036] FIGS. 15 to 17 provide even more detailed views of the front
end shown in FIG. 14.
[0037] FIG. 18 shows a block diagram of a preferred embodiment of
the fluid jet cutting system of the present invention.
[0038] FIG. 19 shows a high pressure water, purge air and abrasive
flow on/off state and relative time illustration.
[0039] FIG. 20 shows in cut-away an upstream gas flow block off
device.
[0040] FIG. 21 illustrates a rear elevational view of the hopper
container and positive air pressure supply means combination;
[0041] FIG. 22 shows a side elevational view of the combination
shown in FIG. 21.
[0042] FIG. 23 shows an upside down view of the combination shown
in FIG. 21.
[0043] FIG. 24 provides a bottom plan view of the combination.
[0044] FIG. 25 shows a perspective view of the positive air
pressure supply means with pressure housing enclosure removed for
clarity.
[0045] FIG. 26 shows an elevational view of that which is shown in
FIG. 25.
[0046] FIG. 27 shows a bottom plan view of that which is shown in
FIG. 25.
[0047] FIG. 28 shows a cross-sectional view taken along
cross-section line B-B in FIG. 27.
[0048] FIG. 29 illustrates the manifold shown in FIG. 26 with added
dash depiction of the non-solid regions of the manifold.
[0049] FIG. 30 provides a cross-sectional view taken along
cross-section line D-D in FIG. 29.
[0050] FIG. 31 provides a schematic view of the air supply
sub-system of the present invention.
[0051] FIG. 32 shows a cross-sectional view of the high pressure
house with protective covering and air feed lines contained
therein.
[0052] FIG. 33 shows a perspective view of the visualization
assembly mounted on one of the grasping prong of the present
invention.
[0053] FIG. 34 shows the visualization assembly in a detached state
and with the protective cover retracted.
[0054] FIG. 35 shows the visualization assembly with the protector
cover in place.
[0055] FIG. 36 shows the adjustable protective sleeve that protects
the telescoping slide bars.
[0056] FIG. 36A shows one of the telescoping bars.
[0057] FIG. 37 shows the nozzle cover placed in abutment with an
object to be cut.
DETAILED DESCRIPTION OF THE INVENTION
[0058] FIGS. 1-10 and 13 illustrate a plurality of embodiments of a
fluid jet cutting system 20 with FIG. 1 illustrating a cut-away
view of a first embodiment that comprises gas purged abrasive feed
assembly 22 in communication with fluid jet cutting nozzle assembly
24 via abrasive feed line 26 (with "line" being in the broad sense
and including, for example, the abrasive passageway extending from
the abrasive hopper or access ports therefore to the interior
nozzle outlet port that opens into the fluid stream passing through
the nozzle). Gas purged abrasive feed assembly 22 comprises means
for introducing positive pressure 28 that is preferably gas based
(e.g., air) and functions to prevent the fluid being supplied to
the fluid jet nozzle (e.g., liquid as in water with or without
liquid additives as in emulsions or cutting promoting chemicals
being illustrative) by way of high pressure line 30, from entering
the abrasive line 26 (e.g., prevents passage of liquid into the
abrasive outlet port in the nozzle and into any portion of the
remainder of the abrasive line leading to that port). The air purge
assembly 22 provides an upstream to downstream air flow in the
abrasive line, and thereby prevents the formation in the abrasive
line of clumps of moistened abrasive "A" either relative to any
abrasive already present in the abrasive line or later introduced
abrasive material which, in either situation, can easily clog the
abrasive line. This purging is operational regardless of the
orientation of the nozzle and thus works particularly well in
addressing the more problematic (less gravity assisted) situations
as where the nozzle, in use, is not arranged either in a true
vertical orientation or essentially vertical (e.g., within 10
degrees of vertical).
[0059] FIG. 1 illustrates a first embodiment of means 22 for
introducing positive pressure into the abrasive line 26 which
comprises an in-line pressure access means 32, such as a
"Y-fitting" as shown, a "T-fitting" (see FIG. 1A) or an alternate
similarly functioning gas access means, installed in the abrasive
line 26 between and in communication with a means to provide
thereto positive pressure as in air compressor 34 (FIG. 18) (e.g.,
provided in-situ or remote with a communication line with a
receiving chamber represented by 34' when dealing with a remote
compressor), with the source of pressurized gas also providing a
potential source for functioning other components in the system as
in an abrasive shut off solenoid. In a preferred embodiment,
fitting 32 is provided at a location in line between the outlet 38
of abrasive hopper container 36 and the abrasive feed line outlet
into the main body 42 of nozzle 40 where the high pressure liquid
and abrasive come into contact prior to being ejected out of the
high pressure nozzle as in through a standard small diameter,
highly wear resistant orifice insert provided in the nozzle.
[0060] FIG. 1 further illustrates the abrasive feed source with air
purge system 22 having means for mounting 44 system 22 on a
hazardous duty robot 46 (FIG. 13) or another alternate movable
support member with a movable support foundation as in the wheeled
or track robot 46 or a fixed foundation support member with means
for moving the nozzle to desired positions as in a manipulation arm
supported, or an entirely fixed platform or fixed support member.
In FIG. 1 there is illustrated mounting means bracket 44 which
provides for robot attachment as shown in FIGS. 9 and 13. Bracket
44 further supports support wall 48 to which is attached manifold
50. Hopper container 36 is supported on the upper surface of
manifold 50 which also provides gas feed channeling. Suspension
bracket 52 is suspended below manifold 50, and is preferably L
shaped and supports abrasive line inlet conduit 54 extending
between the base of bracket 52 and manifold 50 and positioned to
receive abrasive A (e.g., garnet) passing out of hopper container
36 via the converging (e.g., conical) hopper feed outlet 38 (see
also FIG. 6) formed in the central area of manifold 50 and out the
hopper exit tube 56 and into line inlet conduit 54 when the
abrasive line feed stop assembly 58 is in a flow position. The
abrasive is precluded from entry into conduit 54 when stop assembly
58 is in abrasive flow block position (the position shown in FIG.
1).
[0061] Stop assembly 58 is preferably an automated remote
activatable stop which is in gas pressure or electrical
communication via gas or electrical communication line 60 with the
fluid jet cutting system control system (discussed below) and
features a driver 64 (e.g., a solenoid (fluid or electrical),
gearing, or fluid based driver movement to position the stop) for
adjustment of stop plate 62 (e.g., a linear or rotational
adjustment as in a slidingly supported plate for positioning at a
location flush or essentially flush (minimal abrasive leakage) with
the outlet end of the outlet of hopper exit tube 56 when in an
abrasive flow stop mode). Mechanical activation can be carried out
through use of the pressurized air from compressor (or compressor
receiver) 34 via the noted line 60.
[0062] Bracket 44 also provides support to the stop assembly in a
preferred embodiment, although manifold 50 can also support
components in a suspended state. Alternate flow stop means are also
featured under the present invention such as a vertical plug valve
and the like which can be moved between outlet blocked and free
flow access modes, although the illustrated sliding plate is
preferred as it provides disruption free throughflow when in a
removed position, and readily provides for flow orifice size
adjustment.
[0063] FIG. 1 further illustrates, as part of the air purge system
28, air intake port 65 (receiving the end of an air purge feed hose
not shown in FIG. 1) in on/off flow valve 66 suspended by manifold
50. Air fed from the compressor 34 (either compressor itself or
in-feed location from a remote compressor) passes through regulator
68 and its outlet port 70 before traveling to fitting 32 via a
short fitting branch line 72.
[0064] The pressure of the gas is controlled by way of the
regulator in association with compressor output and preferably
maintains the outputted purge air at a pressure between, for
example, 10 to 20 psi, more preferably 12 to 18 psi with 15 psi
being a suitable value in a preferred embodiment. The regulator can
thus provide a means for stepping down a higher pressure compressor
output operating at, for example, 100 to 150 psi (see 34 in FIG.
18). Other pressurize gas providing means include, for example, air
tanks preferably with regulators to provide the desired purging
line pressure.
[0065] Thus, from the Y-fitting 32 pressurized air will pass though
the flexible conduit portion 74 of abrasive line 26 and into the
non-flexible abrasive nozzle inlet conduit 76 forming part of
nozzle body 42. The pressurized air then passes through the
interior mixing region of the nozzle and then exits the fluid jet
cutting system 20 through the nozzle outlet 82 for the cutting
fluid (e.g., mixed water and abrasive) at the end of the nozzle
tube 43 (see FIG. 37). Nozzle tube 43 is surrounded by protective
sleeve 78 which is secured to the internal nozzle tube 43 by way of
hand screw 79. Protective sleeve 78 (e.g., steel) functions to
protect the focus tube (typically formed of more brittle hardened
material to accommodate the abrasive flow) from damage upon contact
with objects (e.g., a vehicle side wall to be cut which provides
for rapid positioning of the nozzle).
[0066] FIG. 37 illustrates protective sleeve 78 having a convoluted
front end which presents diametrically opposed contact points as
well as diametrically opposed recessed areas which provide for
pressure release that allows high pressure fluid to escape through
the sides of the nozzle upon coming into contact with an object
where there is liquid flow. The gas flow is preferably maintained
continuous when in an "on" state and flows from its entry point in
the gas purge path and from that location to the outlet nozzle or
both downstream in that direction and, possibly, upstream, toward
the container or some other upstream non-sealed release location if
there is not a sealed off air blocker or actuator between fitting
32 and the upstream portion of the abrasive feed line 26 or the
abrasive container 36. In such circumstances where there is flow
upstream and downstream to the nozzle relative to the purge air
access location via fitting 32, the purge air volume flow rate of
air is increased such that a sufficient amount of air is supplied
to allow for exiting through the upstream opening as in container
36 and the downstream end of nozzle 40. In either situation, the
air exiting through the nozzle 40 is supplied at a sufficient flow
rate to prevent water from entering the abrasive line. The flow
rate and pressure levels are thus designed to provide for the
purging function of keeping liquid out of the abrasive line, but is
maintained at a relatively low setting to avoid an overly
pressurized system. Also, in the situation where the gas flow is
supplied upstream, it is free to travel in a preferred embodiment
back into the hopper container and provides an abrasive percolating
effect which facilitates non-clumped feed from the container into
the abrasive feed line (e.g., the relatively low pressure provides
for percolation without blow out or flow disruption)
[0067] FIG. 1 further illustrates nozzle assembly 24 having a high
pressure inlet end receptor 80 into which flexible high pressure
line 30 extends at the inlet side and having an outlet extending
into nozzle body 42. The high pressure fluid is fed into receptor
80 and into the interior liquid/abrasive mix region prior to the
cutting mix exiting through nozzle or focus tube 43 and out high
pressure outlet 82. The high pressure flow is preferably generated
by a nozzle supported small orifice insert (not shown) which is
conventional in the art. The gas purging feed assembly preferably
operates to ensure that during times when there is insufficient
vacuum generated by the high pressure cutting fluid passing through
the nozzle (see the above discussion regarding FIG. 2 and the delay
in vacuum generating during early stages of liquid flow), there is
provided positive gas pressure to maintain abrasive line 26, 76
clean of liquid which is of greater concern when situations where
the nozzle is not oriented vertically as in a horizontal or
generally horizontal (having a significant horizontal component as
in more than 10 degrees removed from a vertical orientation) robot
mount or a hand held operation. In situations where it is desired
to have purging air flow during times when there is insufficient
vacuum generating liquid flow, a control process can be carried out
such as a turning on of the gas purge system 22 for a predetermined
time. In this regard reference is made to FIG. 19 which provides a
high pressure liquid/purge air/abrasive flow "on/off" supply
sequence illustration. As seen from FIG. 19, T0 represents the time
when high pressure liquid flow is turned "on" (e.g., an operator
induced "on" button on a control board located at a remote location
from a hazardous duty robot supporting the nozzle). At time T1 the
purge air is switched from its pre-existing "on" state into an
"off" state. In a preferred embodiment, a range for T1 includes
T1=T0+10 sec to T1=T0+20 or 30 seconds, which provides for the
generation of sufficient vacuum generation by the liquid flow in
the system to avoid a nozzle pressure introduction of liquid into
the abrasive line. As further seen from FIG. 19, T2 represent the
time when the abrasive is turned "on" with abrasive flow being
locked out when the purge air is "on". The T2 activity is
preferably automated based on time passage, for example, or
operator controlled (with a lock out of the "on" state for abrasive
flow when T2 is less than T1). T3 represents the time when the
abrasive is turned off either in an automated timer based system
or, more preferably, by operator control. T4 represents the time
when the high pressure liquid supply is turned off by the operator
or in a timer based automated sequence. In a preferred embodiment,
the turning off activation signal for the liquid flow, as in the
operator pressing a liquid flow turn off button, leads to an
automatic turn "on" of the purge air flow and a delay sequence
relative to the actual stoppage of water supply. This is
represented in FIG. 19 by way of the maintenance of the liquid flow
up to T5 upon an activation signal to shut down at T4 at which time
the purge gas is initiated. The liquid flow shut off time T5
preferably ranged in time from T5=T4+10 seconds to T5=T4+20 to 30
seconds. The present invention features control means for
precluding the shut off of liquid flow until after a preset time
period (e.g., 10 to 20 seconds) has expired and the continuation of
liquid flow for a period after above shut off which is helpful in
that the vacuum effect generated by the continued high pressure
fluid supply helps clean out the shutdown abrasive line of
remaining abrasive. FIG. 19 also shows that on the start up end,
the purge air is first placed "on" prior to liquid flow start up
and then continues on with the liquid flow in the on state for 10
to 20 seconds (again to allow for sufficient vacuum build up).
[0068] In FIG. 1A there is illustrated an alternate embodiment of
the present invention featuring fitting 32' shown mounted directly
on nozzle body 42 and thus has a gas introduction location that is
closer to the abrasive line outlet into the liquid abrasive mixing
chamber formed in the central interior of nozzle body 42 than to
the hopper abrasive outlet. The positioning shown in FIG. 1A
entails having a purge gas feed line that is of a similar length as
that of the flexible abrasive feed conduit (e.g., to a less than
200 inch abrasive line length as in 10 inches to 200 inches or 100
to 140 inches for some abrasive conduit positions under the present
invention). Thus, with the fitting associated with the nozzle body
or close thereto, the purge gas supply line length would be the
same or essentially the same as the abrasive line feeding to the
nozzle. Thus, having the fittings at the abrasive hopper as in FIG.
1 provides for a purge air line that is much shorter and thus more
desirable from that standpoint. Additional fitting locations can
also be implemented under the present invention as at a location
intermediate the two illustrated in FIG. 1A.
[0069] In the FIG. 1A embodiment an optional actuator 84 is
illustrated which provides a means for blocking off purge air flow
directed upstream from the fitting location in the abrasive line
26. In this way all supplied air is forced to thereby forcing all
of the air to exit through the nozzle outlet 82. FIG. 20
illustrates an embodiment of actuator 84 which is in the form of a
pinch valve that is preferably automated as in an on/off switch at
that operator control panel. As shown in FIG. 20, actuator 84
includes housing H in which is mounted pinch valve V with the
housing being retained, for example, on a portion of flexible
abrasive line section 74 which threads though an opening in the. In
this way when the pinch valve V is triggered (e.g., a solenoid
drive either electrically or also air line driven--not shown), it
closes off all or a significant portion of upstream purge gas flow,
such that the purge gas flow is focused downstream to the fitting
in the direction of the nozzle outlet. If it is not desired to
block off the abrasive inlet upstream portion of line 26, (e.g., to
provide the percolation effect in the hopper container) the volume
flow rate of air supplied is increased to account for the amount of
air that will exit through the abrasive upstream portion of the
abrasive line such that sufficient purge air still exits through
the nozzle 42.
[0070] Rather than supported at the nozzle assembly 24, the
abrasive line purge fitting can be moved upstream such as an
integrated fitting (represented by Y-fitting 32" in the flexible
conduit portion 74 supplying abrasive between exiting the abrasive
hopper system and before entering the preferred solid abrasive
conduit extension 76 or even further upstream as in the additional
preferred embodiment described above at the hopper assembly
discharge and also as in the below described sealed, pressurizable
enclosure embodiment described below.
[0071] FIGS. 3 to 10 and 21-30 illustrate an alternate "closed
system" embodiment (as compared to the generally "open" system
described above) for preventing fluid from entering the abrasive
line and thus avoiding the prior art problem of clumping of the
abrasive when introduced into the line and the clogging of the
abrasive line. The closed system embodiment of FIGS. 3-10 utilizes
the aforementioned timing sequence for the open system and/or
places reliance, at least in part, on sensor means (primarily
mechanical as described below or an electronic sensor or one or
more of the purge gas, abrasive feed line and pressurized for an
automated switch over (e.g., via mechanical switch over means)
between purge gas supply when needed (when no or insufficient
vacuum generated) and when not needed (e.g., sufficient vacuum
generated--See FIG. 2 for an example).
[0072] As shown in FIGS. 3 to 10 and 21-30 there is featured an
alternate gas purged abrasive feed assembly 88 with abrasive hopper
mount assembly 90 comprising mounting bracket 92 for robot
attachment as shown in FIGS. 9 and 13. As shown in FIGS. 3 to 10,
the upper surface of mounting bracket 92 supports base block 94 on
which is provided water hose guide means 96 which, in a preferred
embodiment features a triangular array 98 of rollers 100 supported
on brackets 102 for the high pressure water hose 30 (see FIG. 13)
which is threaded through the roller set before connection with the
nozzle assembly. The rollers 100 are supported on the triangular
array so as to be free rotating but to have end-to-end spacing
which is smaller than the diameter of the hose 30 to always present
a roller contact surface during the riding of the hose within the
confines presented by the mounted rollers. Mounting bracket 92
further supports support wall 104 to which is attached to manifold
106. Hopper container 108 is supported on the upper surface of
manifold 106. Sealed enclosure 110 is suspended below manifold 106
and as shown in FIGS. 6 and 10 the central area of the upper
surface of manifold 106 includes conical hopper feed outlet 112
provided in the central bottom portion of the abrasive container
108 and includes the hopper outlet port 114 which delivers abrasive
to the inlet opening of the upper region of abrasive line 74 at
abrasive inlet port 26. The manifold also provides a convenient
location for providing a gas passage for introducing the
pressurized air from an external to enclosure location to an
internal to enclosure location.
[0073] Air pressure in the system shown in FIGS. 3-10 will exit the
fluid jet cutting system 14 through the nozzle 40 and the abrasive
container 108. The volume flow rate of air is such that a
sufficient amount of air is supplied to allow for exiting through
the container 108 and the nozzle 40. The air exiting through the
nozzle 40 still prevents water from entering the abrasive line 74.
The enclosure 110 around the abrasive inlet port 113 also prevents
the elements such as wind and blowing rain from interfering with
the flow of abrasive from the container 108 to the abrasive inlet
port 118 (FIG. 10), and thus is particularly well suited for use in
external environments or where the noted elements are present. When
abrasive is flowing, the positive air pressure is removed from the
sealed enclosure 110 and external air is allowed to enter the
enclosure 110 through the (preferably mechanical) pressure
sealing/release means 129 (see FIG. 10--with flap seal 129 mounted
about an aperture formed in a side wall of enclosure 110 with FIG.
10 showing mounting on one wall and FIG. 3 an alternate wall) by
the force of the vacuum resulting from the high pressure water
stream. The design of the pressure sealing/release means 129 is
passive in nature and is closed by the positive air pressure
injected into the enclosure 110, and is opened by the vacuum when
the high pressure water is flowing, and thus operates automatically
with relationship to the timing of when sufficient vacuum is
generated to avoid a wetting of abrasive outside nozzle mixing
chamber. As shown in FIG. 10, means 129 operates relative to a port
formed in an enclosure wall as in a side wall or the bottom wall
illustrated. This port is a circular hole in the enclosure 116
preferably with means 129 having a rubber flap attached on the
interior surface of the enclosure 110.
[0074] FIGS. 3-10 further depict positive air pressure supply means
116 for introducing positive air pressure to be introduced at the
abrasive hopper inlet port. In FIGS. 3-10, the sealed cuboidal
enclosure 110 is suspended below manifold 106 and encapsulates an
exchange area between the hopper outlet port 114 and a further
downstream portion 122 of the abrasive line 124 which exchange area
further includes automatic abrasive flow stop assembly 126 (similar
in function to the 58 described above). Compressor 128 (or a
compressor line reception chamber) supplies positive air pressure
through valve 132, via regulator 134 and regular line 136 which
extends into enclosure 110 via manifold 106 to pressurize the
enclosure to a desired level (e.g. to provide gas pressure and flow
rates similar to those described above in first embodiment). For
example, the gas is fed from compressor source or receiver 128,
through the pressure step down regulator 134, past the on/off valve
132, into a first of two reception ports in the manifold that feeds
into the enclosure 110. A second intake port/channel is also
preferably provided in the manifold for feeding pressurized air
from compressor 34 to the enclosed abrasive flow shut off valve or
stop. Thus, a desired pressure level for the pressurized purge air
and a desired flow rate is maintained
[0075] FIG. 9 provides a close up view of the preferably
transparent container 108 and the abrasive A contained therein.
Container 108 is preferably the sole source of abrasive and is
preferably carried on the hazardous duty robot (e.g., no separate
feed lines needed during hazardous interdiction). Container 108
thus preferably has a volume of about 300+/-50 in.sup.3 a volume
being well suited for use with the high pressure liquid supply of,
for example, about 50,000 psi (e.g. +/-5,000 psi) which is workable
with the flexible high pressure hoses currently available. At the
upper end of container 108 there is provided abrasive feed cap vent
port 140 for venting air out or in the container 108 while at the
same time preventing rain water from entering the container (e.g.,
a flap valve). FIG. 9 also illustrates U-shaped handle 142 for
container cap 143 with the cap preferably being releasable relative
to the cylindrical, transparent main container body shown. For
example, Velcro strap attachment of cap 143 with handle 142
separation for filling the container once empty.
[0076] Purge gas supply flow rates of 5 ft.sup.3/hr to 10
ft.sup.3/hr are illustrative of the flow rates involved when the
upstream gas passage toward hopper is blocked off in a closed
system while 10 ft.sup.3/hr to 12 ft.sup.3/hr illustrative of a
non-blocked off upstream gas flow embodiment. The volume of sealed
enclosure 110 is preferably about 40 in.sup.3.
[0077] With reference to FIGS. 11-17 an additional embodiment of
the present invention is illustrated that features high pressure
nozzle assembly 24 as described previously, attached to a remotely
controlled arm 144 via a manipulator device 146 as in grasping
means (e.g., a gripper, claw, clamp, chuck etc) on a hazardous duty
robot 150 (see FIGS. 13-17). The method of attachment is such that
other intended operations of the robot arm 144 are still available
to the robot operator. It is preferable that the nozzle 24 be
mounted on the grasping means 146 shown supported on robot arm 144
such that it protrudes somewhat past the grasping means 146 to
allow the proper location of the nozzle 24 with respect to the
object being cut. The illustrated "gripper" 146 or "claw" of the
robot 150 is preferably a component that can be moved to be in the
most forward portion of the robot 150 and therefore the nozzle 12
is preferably mounted such that it even further protrudes from the
gripper 146. To enable the continued use of the gripper 146 for
intended purposes, the gripper 146 is not used to grasp the nozzle
24. Instead, nozzle 24 is mounted on one prong or portion 152
(preferably a movable portion) of the gripper 146 by way of a
bracket assembly 154 that is mounted on an exterior side 156 of the
gripper prong 152 (see FIG. 12). This structure leaves the gripper
available for grasping and picking up objects as desired by the
operator.
[0078] FIG. 11 illustrates an exploded view of the nozzle mounting
assembly 158 of the present invention with the above noted cutting
nozzle 24, grasping prong 152 and nozzle attachment assembly 154.
As shown nozzle attachment assembly 154 comprises a first bracket
section 160 with a bolt access hole with bolt (not shown) or
alternate fastening means 162, for engagement with one of a
plurality of threaded reception holes 164 (e.g., three in series
for providing a degree of operator induced adjustment as to the
axial extension of the nozzle outlet port relative to the
supporting gripper prong 152). First bracket section 160 is shown
as having a U-shape with the presentment of a back interior wall
and upper and lower interior walls which are sized for friction
reception of the multisided inlet end 166 of nozzle assembly 24.
Nozzle mounting assembly 158 further comprises second bracket
section 168 which is designed to close off the open end of the
first bracket section 168, and features a plate with upper and
lower fastener holes which receive bolts (not shown) that extend
into bolt reception holes formed in the free ends of the legs of
the U-shaped bracket section 160. The multisided inlet end
(hexagonal cross section depicted) is sized so as to extend out of
the U-shaped enclosure to some extent such that it is placed in a
state of compression when plate 168 is bolted into position.
Additional optional axial stops (e.g., male/female engagement
between multi-sided inlet end 166 and one of the interior walls of
the U-shaped bracket section 160) are also featured under the
present invention.
[0079] FIG. 12 shows the nozzle mounting assembly in an assembled
state In a preferred embodiment the blocking and other components
of the nozzle mount means places the nozzle's central axis at least
1 to 6 inches external to the exterior side of the supporting
gripper prong or exterior wall surface as in a 2 to 3 inch
spacing.
[0080] FIG. 13 shows an illustration of a preferred embodiment of a
hazardous duty robot with mounted hopper mount assembly and nozzle
mounting assembly in operation cutting multi layered plating. As
seen, the nozzle assembly (central axis of focus tube and water
spray) is often positioned at a horizontal orientation or more
horizontal than vertical orientation by the support provided by
robot 150, thus the aforementioned air purge system is highly
effective in this situation in avoiding what would otherwise be a
situation having high probability of clogging difficulties. FIG. 13
also illustrates the retention in position of the high pressure
fluid hose to the exterior side of the hopper mount assembly such
that it can be pulled and retracted (e.g., by robot arm 144)
without getting tangled or crimped in an undesirable location.
FIGS. 15-17 provide closer views of a mounted nozzle assembly 24 on
the manipulator 146 provided on a hazardous duty robot. FIG. 16
also illustrates an alternate hand grasp bolt arrangement for
attaching the second bracket section 96 to the first 94.
[0081] In an alternate embodiment the nozzle support includes a
swivel connector in place of the non-swivel connector C in FIG. 15
at the location where high pressure enters into nozzle assembly 24
and there is further provided means (not shown) for rotation of
nozzle mount 154 (e.g., a hinge lock arrangement provided in the
nozzle mount 154) to provide for an automated rotation of nozzle
assembly from axial position to a radial orientation or reverse
axial position to enable even more axial movement of gripper into a
hole or the like.
[0082] FIG. 18 provides a block diagram for a preferred embodiment
of the present invention describing features making up a preferred
embodiment of fluid jet cutting system 20 of the present invention.
As seen in this illustration there is provided a robot interface
kit and a control system (e.g. processor based) for remote or
automated control of the abrasive supply system, the liquid supply
system and the mechanical movement for those systems as well as the
mechanical and electrical features of the hazardous duty robot
including drive, location finding (e.g., sensed position via
sensing system S supported on telescoping pole P in FIG. 13 and/or
path input) and manipulation of arm 144 and grasping means 146 such
as in the step down concentric cutting sequence described above
based on the degree of grasping means closure either pre-input as
part of a fixed program and/or adjusted by operator determination
during operation. The control means also preferably monitors
characteristics of the pressurized gas system for purging the
abrasive line such as the pressure level in enclosure 110 with a
pressure transducer or the like (not shown) and/or flow rate,
although the above described mechanical vacuum flap provides either
an alternate source of control or one that can be supplemented with
sensed control through use of a transducer or the like.
Alternatively or supplemental thereto, a time based sequence can be
utilized as described above for FIG. 19. For example, there is
featured under the present invention control means for controlling
when the purge air pressure is applied and when not in accordance
to a logic sequence conforming the parameters set forth above for
FIG. 19, as an example.
[0083] Additional benefits of this mounting method are also
realized with robots that have the ability to rotate the gripper
about its axis of symmetry. This includes for example, that the
size of the hole that is to be cut is controlled by the open
position of the gripper. For a large hole, open the gripper
completely. For a small hole, close the gripper completely, or for
three or more layers step down in intermediate fashion between full
open and full closed extreme locations. The cut is completed by
simply rotating the gripper set at the desired size. This design
enables cutting access holes in multi-layer structures whose layers
may be spaced apart several inches. One suitable process sequence
comprises: (1) Open the gripper completely to cut the largest hole
possible. (2) Close the gripper such that the nozzle clears the
hole previously cut. (3) Extend the gripper arm in an axial manner
to position the nozzle to enable cutting of the next surface (e.g.,
axial movement to achieve layer contact with the preferred cutting
location relative to the exiting spray or jet of abrasive/fluid
combination). (4) This process can be repeated until the final
layer is cut. The limitation is the reach extent of the robot arm.
A second benefit is that the cutting path can be easily retraced
since only one degree of freedom of movement is exercised. This
allows the operator to ensure that the hole is completely cut
through prior to moving the robot for the next operation. The
versatility of multi-dimensional cutting allows for greater
flexibility in cutting through multi-layer structures such as
multi-panel vehicle (e.g., van or truck) body structures as it
avoids stream degradation due to contact with a previous cut
layer.
[0084] FIGS. 21 to 24 show the combination of the abrasive hopper
container 108 and positive air pressure supply means 116 separated
from mount bracket 92 earlier described for FIG. 3. As shown 106
hopper container 108 is mounted on manifold (e.g., an integral or
secured, sealed relationship). Abrasive purge gas line (the "blue"
line--noted in FIG. 31) extending from compressor 34 (not shown in
FIG. 30 since an external source operating at, for example, 100 to
150 psi pressurized air supply) feeds into inlet elbow 170 which
extends into regulator 134. Regulator 134 functions to step down
the purge gas line pressure from the 100 to 150 psi. down to, for
example, 10-20 psi. The lower pressure purge gas is then shown in
FIGS. 21 to 24 as feeding into control valve 132 designed to either
preclude or allow purge air flow therethrough.
[0085] In addition, in a preferred embodiment, there is a second
control gas line (the "green" line noted in FIG. 31) which extends
into manifold inlet 133 which opens into manifold port 135 as shown
in FIG. 36. FIGS. 23-26 show control line 172 extending from
manifold 106 (FIG. 30) also into communication with control valve
132. Also, shown in FIGS. 23 to 26 is the abrasive purge gas
conduct 174 which extends between control valve 132 and manifold
106.
[0086] FIGS. 29 and 30 illustrate manifold 106 and the interior gas
passageways formed therein. FIG. 30 shows purge gas inlet
passageway 176 receiving gas from line 174 via connection port 175.
Manifold passageway has an interior end that opens into enclosure
110 (enclosure represented by the dash line square in FIG. 30) via
access port 178. The opposite end of passageway 176 preferably
includes a pressure gauge 180 plugging the other opening in
manifold line 176. Purge gas entering port 175 thus feeds
pressurizing gas through access port 178 to pressurize enclosure
110 and to further provides the downstream purge gas line pressure
discussed above.
[0087] FIG. 30 with the enclosure cover removed for better
visibility of the abrasive flow control assembly 158, illustrates
manifold abrasive stop activation line 182 with control valve
outlet port 184 in communication with control valve 132 via control
line 172. Manifold abrasive stop activation line has an interior
end 186 which has activated line feed port 188 that communicates
control line gas from manifold activation line 182 to activation
feed line 190 that feeds into an activator such as a air pressure
driven solenoid 192 as shown in FIGS. 25-27. Solenoid 192 includes
a connector 194 for operating abrasive feed line stop assembly 58.
Solenoid 192 has an outlet conduit 195 extending back into contact
with manifold 106 at entrance port 196. As shown in FIG. 30,
entrance port 196 opens into another manifold conduit 198 which
exits out at sintered outlet 200.
[0088] FIG. 28 provides a close up view of the abrasive flow stop
assembly 58 driven by solenoid 192 via connector 194 to either an
open or closed or blocking state with stop plate SP which is
pivotably supported at one end by shaft SH threaded into manifold
106. Thus when solenoid 192 is activated its pusher bar moves stop
plate SP against the return bias effect of the spring connected at
the end opposite to the pivot shaft as shown in FIG. 27. By
adjusting, for example, the threaded connection of driver connector
194, a mulit-key/slot arrangement relative to the pivot shaft
connection and/or a threaded stop pin SM extending from the
interior of the enclosure 110 into abutment with the edge of stop
plate SP as shown in FIG. 27
[0089] FIG. 32, illustrates a preferred manner of the delivery of
pressurized gas to the abrasive purge gas system and the abrasive
feed line stop assembly. As shown in FIGS. 9 and 32, there is high
pressure hose assembly 30 which extends from the remote water
source 202 (FIG. 18) which in a preferred embodiment is a self
contained 60 gallon water tank which is sufficient for remote
operation without need for public source water or a large body of
water (e.g., a 60 gallon tank supplied in a support movable
vehicle). The water derived from fluid source 202 is intensified
with intensifier 204 to achieve the desired high pressure level
(e.g., 50,000 PSI at 0.6 gpm) and fed through high pressure hose
assembly 30 of, for example, 300 feet in length to hose guide means
96 and into the nozzle fluid inlet end of nozzle 40. FIG. 32 shows
a preferred arrangement featuring internal high pressure hose 206
preferably formed of a steel mesh enhanced flexible rubber material
covered outer (vinyl) protection sketch 208. Within the annular
cavity formed between hose 206 and sketch 208 there is extended the
abrasive purge supply line 210 (blue) and the abrasive flow
blockage control line (green) 212 feeding respectively inlets 170
(abrasive purge gas line) and 133 (abrasive flow stop assembly
control).
[0090] FIG. 17 illustrates a first embodiment of visualization
assembly 214 shown in a fixed support location on the manipulator
arm assembly 144. FIG. 33 shows an alternate embodiment of the
visualization means (216) mounted to the exterior surface of one of
the grasping prong 152 of gripper 146 (e.g., the opposite gripper
prong as that supporting the nozzle). Visualization assembly 216
comprises video camera 218 contained in protective metal housing
220 which entirely encompasses camera 218 but for the lens and
reception aperture for receiving power and feed back cable set 222.
Housing 220 is releasably secured with bolts 224 to mounting
bracket 226 which is L-shaped and secured to the upper surface of
grasping prong 152 with bolt set 228. FIGS. 33 and 35 illustrate
that the horizontal leg 225 of L-shaped bracket 226 in preferably
notched to comfort in the outline of the curving profile for
gripper 157. Camera housing 321 is further connected to housing
bracket 230 to which is connected light 228 and shield support.
Shield 232 is shown pivotably secured to shield support 231. Light
228 also is protected by an exterior metal housing which is
connected to housing bracket 230.
[0091] Shield 232 is preferably electrically or air driven by a
driver (not shown) which is positioned within an enclosed space
provided by shield support having a rotatable shaft that rotates to
position the shield in either an visualization mode shown in FIGS.
33 and 34 or the protection mode shown in FIG. 35, varies other
shielding assemblies or also featured in the present invention such
as an Iris design (also operable by the rotation shaft driver
discussed above).
[0092] Thus visualization means 216 is arranged external to the
"other" grasping prong 152 so as not to interfere with its gripping
operation in the same manner as the outlet nozzle for the fluid jet
cutter assembly of the present invention. Also by manipulating
(e.g., collapsing) the gripper prong 152, the visualization means
can be inserted into a formed cut out and then further manipulated
(e.g., expanded from the collapsed position and rotates above to
visualize an opening up accessed area).
[0093] FIGS. 36 and 36A illustrate an additional feature of the
present invention which includes protective coverage of 234
preferably formed of a water proof, durable material such as a
vinyl material. Covering 234 is designed to cover over the
telescoping border area between the two component manipulator arm
144 housing first telescoping a piece 236 which receives and
rectangular cross-sectioned arm component 238 (FIG. 17) to which
gripper assembly 146 is mounted. Arm component 238 is sized for
reception within the interior of arm component 144 for sliding
retraction in and out pursuant the appropriate control signals.
FIG. 36A illustrates arm combination 144 with its low friction
(e.g., brass) slides plates along which arm component 238 slides.
As abrasive can readily disrupt smooth slide functioning, the
present invention includes cover 234 which is sufficiently secured
at its end to the arm components 236 and 238 so as to preclude
abrasive from gaining access to this slide region.
[0094] Those skilled in the art can now appreciate from the
foregoing description that the broad teachings of the present
invention can be implemented in a variety of forms. Therefore,
while this invention has been described in connection with
particular examples thereof, the true scope of the invention should
not be so limited since other modifications will become apparent to
the skilled practitioner upon a study of the drawings,
specification and following claims.
* * * * *