U.S. patent number RE33,160 [Application Number 07/125,578] was granted by the patent office on 1990-02-06 for method and apparatus for inspecting lateral lines.
This patent grant is currently assigned to Cues, Inc.. Invention is credited to Kenneth R. Guthrie, James R. Martin.
United States Patent |
RE33,160 |
Guthrie , et al. |
February 6, 1990 |
Method and apparatus for inspecting lateral lines
Abstract
Detecting and locating leaks in building service lateral sewer
pipelines is accomplished under remote control by inserting a
lateral inspection television camera into the lateral pipeline from
a main sewer pipeline. The lateral inspection camera is stored in a
generally cylindrical launcher mechanism having a camera port
opening through which the lateral camera may be projected and
retracted using a hollow elongated and flexible push rod. The
launcher is moved longitudinally in the main pipeline, along with a
main television camera, until an entrance opening to a service
lateral pipeline is viewed via the main camera. The launcher
mechanism may also be rotated in order to properly align the camera
aperture with the entrance to the lateral pipeline. The lateral
camera can be propelled into the lateral pipeline by means of motor
driven pinch rollers in the launcher mechanism pushing the push
rod. Electrical power and video signals for the miniature camera
are transmitted through a cable disposed within the push rod. An
electronic switch is disposed in the launcher mechanism and is
selectively actuable from a remote control station to effect
alternative transmission of the lateral camera video signal and the
main camera video signal to the remote control station.
Inventors: |
Guthrie; Kenneth R. (Orlando,
FL), Martin; James R. (Orangevale, CA) |
Assignee: |
Cues, Inc. (Orlando,
FL)
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Family
ID: |
26823708 |
Appl.
No.: |
07/125,578 |
Filed: |
November 25, 1987 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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Reissue of: |
776163 |
Sep 13, 1985 |
04651558 |
Mar 24, 1987 |
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Current U.S.
Class: |
73/40.5R;
348/84 |
Current CPC
Class: |
E03F
7/12 (20130101); F16L 55/28 (20130101); G01M
3/005 (20130101); G01M 3/38 (20130101) |
Current International
Class: |
E03F
7/00 (20060101); E03F 7/12 (20060101); F16L
55/28 (20060101); F16L 55/26 (20060101); G01M
3/00 (20060101); G01M 3/38 (20060101); H04N
007/18 () |
Field of
Search: |
;138/93,94 ;285/93
;358/100,106 ;73/4.5R,40 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2734556 |
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Feb 1979 |
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DE |
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2908351 |
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Sep 1980 |
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DE |
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Primary Examiner: Williams; Hezron E.
Attorney, Agent or Firm: Epstein, Edell & Retzer
Claims
What is claimed is:
1. Apparatus for inspecting a building service lateral sewer
pipeline from a lateral opening in a main sewer .[.pipeline.].
.Iadd.pipeline .Iaddend.at which the lateral .[.end.]. .Iadd.and
.Iaddend.main pipelines intersect, said apparatus comprising:
a lateral television camera of sufficiently small size to fit in
said lateral pipeline;
a lateral signal conduction cable connected to said lateral camera
for delivering electrical signals required to operate the lateral
camera and sending a lateral video signal representing an image
viewed by the lateral camera;
a hollow elongated flexible push rod having a first end secured to
said lateral camera and a second end, said push rod having a
sufficient longitudinally compressive rigidity to push said lateral
camera along said lateral pipeline when moved longitudinally into
said lateral pipeline, and sufficient transverse flexibility to
follow bends in said lateral pipeline when moved longitudinally
into said lateral pipeline;
wherein said lateral cable is disposed inside said hollow push
rod;
launcher means, movable longitudinally in said main pipeline, for
selectively extending said lateral camera and push rod into, and
retracting said lateral camera and push rod from, said lateral
pipeline through said opening from said main pipeline; and
means for selectively transmitting said lateral video signal along
said main pipeline to a control station located remote from said
lateral pipeline.
2. The apparatus according to claim 1 wherein said launcher means
includes rotatably drivable roller means for engaging and
propelling said push rod alternatively in first and second
longitudinal directions.
3. The apparatus according to claim 2 further comprising reversible
motor means for selectively rotatably driving said roller means in
two alternative rotatable directions.
4. The apparatus according to claim 3 further comprising:
monitor means for providing an electrical length measurement pulse
in response to extension of each longitudinal section of
predetermined length of said push rod into said lateral pipeline;
and
means for conducting each length measurement pulse to said control
station.
5. The apparatus according to claim 1 further comprising:
a main television camera movable with said launcher means in said
main pipeline for viewing the interior of said main pipeline and
providing a main video signal representing an image viewed by said
main camera; and
switching means disposed in said launcher means and controlled from
said control station for alternatively transmitting said main and
lateral video signals to said control station.
6. The apparatus according to claim 5 further comprising:
illumination means on said lateral camera for illuminating the
image viewed by said lateral camera, said illumination means being
selectively actuable in response to an illumination signal
initiated at said control station;
wherein said switching means is responsive to the absence of said
illumination signal for transmitting said main video signal to said
control station, and responsive to the presence of said
illumination signal for transmitting said lateral video signal to
said control station.
7. The apparatus according to claim 5 wherein said launcher means
includes rotatably drivable roller means for engaging and
propelling said push rod alternatively in first and second
longitudinal directions, and further comprising reversible motor
means for selectively rotatably driving said roller means in two
alternative rotational directions.
8. The apparatus according to claim 5 further comprising:
monitor means for providing an electrical length measurement pulse
in response to extension of each longitudinal section of
predetermined length of said push rod into said lateral pipeline;
and
means for conducting each length measurement pulse to said control
station.
9. The apparatus according to claim 5 wherein the second end of
said push rod is open and extends beyond the confines of said
launcher means when said push rod is in a fully retracted position
relative to said lateral pipeline, said lateral signal conduction
cable extending out from said open second end and into said
launcher means.
10. The apparatus according to claim 1 further comprising:
a selectively rotatable portion of said launcher means having a
camera port therein and rotatable about an axis extending
longitudinally in said main pipeline, said camera port serving as
an ingress and egress opening in said launcher means for said
lateral camera and said push rod, wherein said rotatable portion is
rotatable to permit angular alignment of said camera port with said
lateral opening.
11. The apparatus according to claim 10 wherein said launcher means
includes rotatably drivable roller means for engaging and
propelling said push rod alternatively in first and second
longitudinal directions, and further comprising reversible motor
means for selectively rotatably driving said roller means in two
alternative rotational directions.
12. The apparatus according to claim 10 further comprising:
a main television camera movable with said launcher means in said
main pipeline for viewing the interior of said main pipeline and
providing a main video signal representing an image viewed by said
main camera; and
switching means disposed in said launcher means and controlled from
said control station for alternatively transmitting said main and
lateral video signals to said control station.
13. The apparatus according to claim 12 wherein the second end of
said push rod is open and extends beyond the confines of said
launcher means when said push rod is in a fully retracted position
relative to said lateral pipeline, said lateral signal conduction
cable extending out from said open second end and into said
launcher means.
14. The apparatus according to claim 10 further comprising:
a main television camera movable with said launcher means in said
main pipeline for viewing said main pipeline and providing a main
video signal representing an image viewed by said main camera;
switching means disposed in said launcher means and controlled from
said control station for alternatively transmitting said main and
lateral video signal to said control station;
sled means for supporting said main camera in said main pipeline;
and
means for connecting said sled means to said launcher means in
longitudinal alignment to permit both the launcher means and sled
means to be moved together longitudinally in said main
pipeline;
wherein said main camera is oriented to view said launcher means
and portions of the main pipeline surrounding said launcher means
to permit observation of longitudinal alignment between said camera
port and said lateral opening.
15. Apparatus for inspecting a building service lateral sewer
pipeline from a lateral opening in a main sewer pipeline at which
the lateral and main pipelines intersect, said apparatus
comprising:
a lateral television camera of sufficiently small size to fit in
said lateral pipeline;
a lateral signal conduction cable connected to said lateral camera
for delivering electrical signals required to operate the lateral
camera and sending a lateral video signal representing an image
viewed by the lateral camera;
a hollow flexible push rod having a first end secured to said
camera and a second end, said push rod having sufficient
longitudinally compressive rigidity to push said camera along said
lateral pipeline when moved longitudinally into said lateral
pipeline, and sufficient transverse flexibility to follow bends in
said lateral pipeline when moved longitudinally into said lateral
pipeline;
launcher means, movable longitudinally in said main pipeline, for
selectively extending said lateral camera and push rod into, and
retracting said lateral camera and push rod from said lateral
pipeline through said lateral opening from said main pipeline;
a main television camera movable with said launcher means in said
main pipeline for viewing the interior of said main pipeline and
providing a main video signal representing an image viewed by said
main camera;
a selectively rotatable portion of said launcher means having a
camera port therein and rotatable about an axis extending
longitudinally in said main pipeline, said camera port serving as
an ingress and egress opening in said launcher means for said
lateral camera and said push rod, wherein said rotatable portion is
rotatable to permit angular alignment of said camera port with said
lateral opening;
sled means for supporting said main camera in said main
pipeline;
means for connecting said sled means to said launcher means in
longitudinal alignment to permit both the launcher means and sled
means to be moved longitudinally within said main pipeline;
wherein said main camera is oriented to view said launcher means
and portions of the main pipeline surrounding said launcher means
to permit observation of longitudinal alignment between said camera
port and said lateral opening.
16. The apparatus according to claim 15 further comprising:
monitor means for providing an electrical length measurement pulse
in response to extension of each predetermined length of said push
rod into said lateral pipeline, and
means for conducting each length measurement pulse to a remote
control station.
17. The apparatus according to claim 15 further comprising:
switching means disposed in said launcher means and controlled from
a remote control station for alternatively transmitting said main
and lateral video signals to said control station.
18. The apparatus according to claim 15 wherein the second end of
said push rod is open and extends beyond the confines of said
launcher means when said push rod is in a fully retracted position
relative to said lateral pipeline, said lateral signal conduction
cable extending out from said open second end and into said
launcher means.
19. A method for inspecting a building service lateral sewer
pipeline from a lateral opening in a main sewer pipeline at which
the lateral and main pipelines intersect, said method comprising
the steps of:
locating said lateral opening; aligning a camera port in a camera
launching mechanism with said lateral opening;
extending a miniature television camera through said lateral
opening and along said lateral pipeline by pushing said miniature
camera with a hollow elongated flexible push rod secured to the
miniature camera; and
conducting electrical signals between said miniature camera and a
launcher mechanism disposed in said main pipeline via an electrical
cable disposed interiorly of said push rod.
20. The method according to claim 19 wherein said step of
.[.detecting.]. .Iadd.locating .Iaddend.employs a main television
camera movable in said main pipeline with said launcher mechanism
and disposed to view a portion of the main pipeline interior
surrounding said launcher mechanism, said method further comprising
the step of:
alternatively transmitting the video signal from said main camera
and the video signal from said miniature camera to a remote control
station by switching the video signals at said launcher mechanism.
.Iadd.
21. Apparatus for inspecting a building service lateral sewer
pipeline from a lateral opening in a main sewer pipeline at which
the lateral and main pipelines intersect, said apparatus
comprising:
a lateral television camera of sufficiently small size to fit in
said lateral pipeline;
a lateral signal conduction cable connected to said lateral camera
from a remote location for delivering electrical signals required
to operate the lateral camera and sending a lateral video signal
representing an image viewed by the lateral camera;
an elongated flexible push rod having a first end secured to said
lateral camera and a second end, said push rod having sufficient
longitudinally compressive rigidity to push said lateral camera
along said lateral pipeline when moved longitudinally into said
lateral pipeline from said lateral opening, and sufficient
transverse flexibility to follow bends in said lateral pipeline
when moved longitudinally therein; and
means for selectively extending said push rod and said lateral
camera along with said lateral cable into, and retracting said
lateral camera and said push rod along with said lateral cable
from, said lateral pipeline via said lateral opening..Iaddend.
.Iadd.22. The apparatus according to claim 21 wherein said push rod
is hollow, and wherein said lateral cable is disposed inside said
hollow push rod..Iaddend. .Iadd.23. The apparatus according to
claim 21 further comprising guide means, movable longitudinally in
said main pipeline, for guiding said push rod into said
lateral opening..Iaddend. .Iadd.24. The apparatus according to
claim 23 further comprising:
a selectively rotatable portion of said guide means having a camera
port therein and rotatable about an axis extending longitudinally
in said main pipeline, said camera port serving as an ingress and
egress opening in said guide means for said lateral camera and said
push rod, wherein said rotatable portion is rotatable to permit
angular alignment of said camera port with said lateral
opening..Iaddend. .Iadd.25. The apparatus according to claim 21
wherein said means comprises:
launcher means, movable longitudinally in said main pipe line, for
selectively extending said lateral camera and push rod into, said
retracting said lateral camera and push rod from, said lateral
pipeline through said opening from said main pipeline; and,
wherein said launcher means includes rotatably driven roller means
for engaging and propelling said push rod alternatively in first
and second longitudinal directions, and further comprising
reversible motor means for selectively rotatably driving said
roller means in two alternative rotational directions. .Iaddend.
.Iadd.26. A method for inspecting a building service lateral sewer
pipeline from a lateral opening in a main sewer pipeline at which
the lateral and main pipelines intersect, said method comprising
the steps of:
locating said lateral opening;
aligning a camera port in a camera guide with said lateral
opening;
extending a miniature television camera through said lateral
opening and along the lateral pipeline by pushing said miniature
camera with an elongated flexible push rod secured to the miniature
camera; and
conducting electrical signals between said miniature camera and a
remote location via an electrical cable connected to said
camera..Iaddend.
.Iadd. 7. The method according to claim 26 wherein a lateral signal
conduction cable delivers electrical signals required to operate
said camera and sends a lateral video signal representing an image
viewed by said camera, said method further comprising the step
of:
extending said cable along with said camera and said push rod into
said
lateral pipeline via said lateral opening..Iaddend. .Iadd.28.
Pipeline inspection apparatus for use in inspecting a lateral
pipeline that enters a generally horizontal main pipeline
comprising
(A) an inspection camera that is sized to fit within said
pipelines,
(A) an elongated transporting member having one end connected to
said camera and which is adapted to initially move in a generally
horizontal path along the interior of said main pipeline, said
elongated transporting member having sufficient flexibility that a
portion thereof can be deflected at an angle reflective to the
remainder of the elongated transporting member,
(C) a supporting assembly sized to fit within and rest upon the
lower internal surface of said main pipeline, said supporting
assembly being arranged to support the portion of said elongated
transporting member that is adjacent said camera and including
(1) drive means which engages said elongated transporting member so
that activation of the drive means can move said elongated
transporting member longitudinally through said pipelines, and
(2) adjustment means for adjusting the angular disposition of a
portion of said elongated flexible transporting member that is
adjacent said camera so that the camera is movable between a
transport position in which the viewing end of the camera faces a
first direction, and an inspection position in which the said
viewing end of the camera faces a direction at an angle to said
first direction, and the camera can be propelled in said angled
direction by activating said drive means, the elongated flexible
transporting member undergoing a change in direction in passing
through
the support assembly..Iaddend. .Iadd.29. Apparatus according to
claim 28 wherein said drive means comprises a pair of pulleys
defining a nip through which said elongated transporting member
passes and a drive motor drivingly connected to one of said
pulleys..Iaddend.
Description
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates to a method and apparatus for
inspecting building service lateral connection lines in sewer
systems. More particularly, the present invention relates to a
method and apparatus for detecting and locating leakage-causing
defects in building service lateral sewer lines.
2. Discussion of the Prior Art
Most localities have long been plagued by massive amounts of
non-sewage water that taxes the capacities of water treatment
facilities, which capacities might otherwise be more than
sufficient to handle the actual sewage generated by the area
population. Inflow (i.e., water entering the system from roof
leaders, storm drains and other sources as a result of rainfall)
and infiltration (i.e., the ground water entering the system
through defects in pipes, joints, service connections, and
manholes) account for as much as 35% of the water transported to
treatment plants. The cost of transportation and treatment of this
extraneous flow can run into the millions of dollars per year.
It has been found that most of the infiltration in sewer collection
systems results from leaks in building service lateral sewer pipes.
Conventionally, identification and repair of leaks in service
laterals requires excavation and/or access to the buildings
serviced by the laterals. This approach is costly as well as
disruptive of activities in and around the building. An improved
method and apparatus for sealing leaks in building service lateral
sewer pipes is described and illustrated in U.S. Pat. No. 4,484,602
(Guthrie). Also described in that patent is a technique for
detecting leaks in a service lateral whereby: the main sewer pipe
is sealed at opposite sides of the lateral entrance; an inflatable
elongated tube is extended into the lateral pipe to create a seal
against the inner surface of the lateral remote from the entrance
but creating an annular space between the tube and the lateral pipe
intermediate the entrance and the seal; pressurized gas is
delivered to the annular space; and a pressure transducer monitors
the pressure in the annular space to determine whether or not a
leak is present in the pipe. This leak detection approach has
limitations in that it cannot pinpoint the location of a detected
leak, and the pressure transducer is often not sufficiently
sensitive to detect very small pressure changes caused by very
small leaks.
OBJECTS AND SUMMARY OF THE INVENTION
It is an object of the present invention to provide a method and
apparatus for detecting and locating leaks in building service
lateral sewer pipes.
It is another object of the present invention to provide an
environmentally acceptable method and apparatus, which is also
acceptable to building owners and users, for detecting and locating
leaks in building service lateral sewer pipes.
Still another object of the present invention is to provide a
method and apparatus for detecting and locating leaks in building
service lateral sewer pipes without requiring excavation or
disruption of use of the building served by the pipes.
It is a further object of the present invention to provide a method
and apparatus for detecting and locating leaks in building service
lateral sewer pipes from a location in a sewer main without
requiring that a section of the main be sealed on opposite sides of
the entrance to the lateral.
Yet another object of the present invention is to provide a method
and apparatus for detecting and locating leaks in building service
lateral sewer pipes internally from a sewer main line as part of a
normal section-by-section inspection program of the overall
collection system.
In accordance with the present invention a lateral inspection
system uses closed circuit television to detect and locate leaks in
a building service lateral sewer pipe. The system includes three
main components: a lateral inspection camera; a main line
inspection camera; and a lateral camera launcher. The inspection
process involves inserting the main line inspection camera, with
the lateral camera launcher attached, into the sewer main via
access manholes. Once in the pipeline, the devices are slowly
pulled via a winch cable through the pipeline until the building
service lateral to be inspected is observed, via the main line
closed circuit television camera, on a receiving monitor located
above ground in a mobile studio. Utilizing the main-line camera to
locate and position the lateral camera launcher, the opening from
the main line to the lateral is aligned with an opening in the
launcher from which the lateral inspection camera exits from the
launcher and enters the building service lateral. Alignment is
accomplished by moving the launcher longitudinally forward or
backward in the main sewer line and by rotating the center segment
of the launcher about the launcher axis.
Once the launcher opening is aligned with the building service
lateral, the lateral inspection camera is propelled into the
lateral pipe. The lateral inspection camera is propelled by means
of two sets of pinch rollers, driven by variable speed and
reversible electric motors, pushing a coiled flexible push rod.
This push rod contains all electric wiring for the lateral camera.
When the lateral inspection camera is in the totally retracted
position (i.e., contained inside the launcher), the push rod
extends rearwardly from the back to the launcher and rests in the
main sewer pipe. When the lateral inspection camera begins its
entry into the building service lateral, the video signal, camera
power and lighthead power are electronically switched within the
launcher from the main line inspection camera to the lateral
inspection camera. This condition is maintained as the lateral
inspection camera is propelled up through the building service
lateral pipe to the full extent of the push rod. After the push rod
is fully retracted, and with the lateral inspection camera resting
inside the launcher, video signal is switched back to the main line
inspection camera. The devices are then pulled forward and
positioned at the next building service lateral to be inspected.
The process is repeated as desired until all of the building
service laterals within the manhole reach have been inspected.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and still further objects, features and advantages of the
present invention will become apparent upon consideration of the
following detailed description of a specific embodiment thereof,
especially when taken in conjunction with the accompanying
drawings, wherein:
FIG. 1 is a diagrammatic illustration of the lateral inspection
system of the present invention deployed in a main sewer line
adjacent an opening to a building service lateral line to be
serviced;
FIG. 2 is a side view in partial phantom of a lateral inspection
camera employed as part of the system of FIG. 1;
FIG. 3 is a front view of the camera of FIG. 2;
FIG. 4 is a broken side view in partial section of the launcher
assembly, including the assembly housing, employed in the system of
FIG. 1;
FIG. 5 is a side view of the launcher unit employed in the assembly
of FIG. 4;
FIG. 6 is an end view of the launcher unit of FIG. 5;
FIG. 7 is a top view of the launcher unit of FIG. 5;
FIG. 8 is a view in section taken along lines 8--8 of FIG. 5;
FIG. 9 is a view in section taken along lines 9--9 of FIG. 5;
FIG. 10 is a view in section taken along lines 10--10 of FIG.
6;
FIG. 11 is a view in section taken along lines 11--11 of FIG.
6;
FIG. 12 is a view in section taken along lines 12--12 of FIG. 6;
and
FIG. 13 is a schematic diagram of the electrical circuit employed
in the launcher assembly of FIG. 4.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring specifically to FIG. 1 of the accompanying drawings, a
main sewer line is generally designated by the reference numeral
110 and has a building service lateral pipeline 109 extending
therefrom. The flow in the main line 110 is in the direction from
left to right as viewed in FIG. 1. The lateral line 109 is oriented
at an angle (i.e., typically 45.degree.) to the main line 110, as
in the case with most present day sewer line systems. This angling
of the lateral pipeline relative to the main line is done in order
to permit orderly flow into the main line without a back-up of
solid sewage at the opening 108 at which the main and lateral lines
intersect.
A lateral camera launcher mechanism 111, described in greater
detail hereinbelow, is disposed in the main line 110 and includes a
camera aperture 112 aligned with the lateral opening 108 in a
manner described subsequently. The launcher 111 has a generally
cylindrical configuration with conventional skid members 3 disposed
at opposite ends to facilitate smooth translation of the launcher
along the interior walls of the main pipeline 110. The portion of
the launcher mechanism intermediate the skid members 3 is rotatable
about the longitudinal axis of the launcher mechanism (and the
longitudinal axis of the main pipeline when the launcher mechanism
is deployed therein) relative to the skid members. A miniature
camera 114 is shown diagrammatically projecting from camera
aperture 112 in the rotatable portion of the launcher housing. The
distal end of miniature lateral camera 114 is secured to one end of
a push rod 94. This push rod takes the form of a hollow elongated
coiled steel cable used to push camera 114 through lateral opening
108 and along the lateral pipeline 109. For this purpose, the push
rod 94 must have sufficient longitudinally compressive rigidity as
not to buckle when pushing the camera through the lateral pipeline.
In addition, push rod 94 must have sufficient transverse
flexibility to permit the rod to follow bends of at least
90.degree. in the lateral pipeline 109. In the fully retracted
position of camera 114, as illustrated in FIG. 1, push rod 94
extends out from the rearward end of launcher mechanism 11.
An electrical cable 119 provides electrical connections between
circuitry located within launcher mechanism 111 and camera 114.
This cable 119 is disposed within push rod 94 and extends from the
open end of the push rod 94, remote from camera 114, and into the
launcher mechanism 111.
A main line television camera 113 is mounted on a sled 115 to
permit camera 113 to be smoothly translated longitudinally along
the main pipeline 110. A pair of tow lines 116 (only one
illustrated in FIG. 1) extend between the forward skid members 3 of
launcher mechanism 111 and sled 115 so that, if the sled is pulled
upstream in the main pipeline 110 (i.e., to the left in FIG. 1),
the launcher mechanism 111 is towed by the sled 115. Main camera
113 is secured to as to view portions of the interior wall of main
pipeline 110 which surround the launcher mechanism 111. The use of
such television cameras as part of a closed circuit television
system in conjunction with sewer line inspection and packing
systems is well known, as described in U.S. Pat. No. 4,484,602 and
in U.S. Pat. No. 3,750,711. The lens of camera 113 has a
sufficiently wide viewing angle to permit observers at a remote
television monitor to determine when the camera aperture 112 in the
launcher mechanism is longitudinally aligned with lateral opening
108. The television monitor is typically located in a van or other
remote control operator station disposed above-ground proximate an
access manhole.
Electrical connections between the circuitry within launcher
mechanism 111 and camera 113 is provided by means of a cable 117
having a female cable connector 118 at its distal end. Connector
118 mates with a male connector 120 disposed at the camera
assembly. A tow line 121 is secured to the forward end of sled 115
by means of a tow cable snapswivel connection 122. Tow cable 121
permits the sled 115 and camera 113 to be towed in an upstream
direction in main line 110. As described above, tow lines 116 cause
the launcher 111 to be towed along with the camera and sled.
At the downstream end of the launcher, an electrical cable 123
extends from the launcher to a female cable connector 124. Cable
123 carries all of the electrical connections required between the
remote operator control station (not illustrated) and each of the
launcher mechanism, lateral camera 114, and main camera 113. A
female cable connector 124 is secured to cable 123 and mates with a
male cable connector 125 secured to a further electrical cable 126.
Cable 126 carries all of the connections back to the remote control
station. A strain relief device 127, conventional in nature,
prevents rupture of the cable during a towing procedure. Cable 126,
downstream of the strain relief device 127, serves as a tow cable
for permitting the launcher mechanisms 111 and main camera sled 115
to be pulled back toward the access manhole proximate the remote
control station. A tow cable snapswivel member 128 is disposed
proximate the stain relief member 127 and includes a separate
extension portion of the tow cable which connects to the downstream
skid members 3 of launcher mechanism 111. In this manner, the
entire assembly may be pulled downstream by exerting forces (to the
right in FIG. 1) through electrical cable 126 and tow cable
129.
In deploying the system illustrated in FIG. 1, tow cable 121 at the
upstream end of the system is engaged by a winch located at an
upstream access manhole. The components illustrated in FIG. 1 are
positioned at a downstream manhole at which the mobile monitoring
station is located. The winch is then actuated by the operator in
the remote control station to pull the assembly until the video
image on the monitor from camera 113 indicates that the camera
aperture 112 launcher mechanism 111 is longitudinally aligned with
a lateral opening 108 for a building service lateral pipeline. At
such time, the towing is terminated and the central portion of the
launcher mechanism housing is rotated to angularly align camera
aperture 112 with lateral opening 108. Again, this procedure is
viewed by the operator at the remote control station and controlled
accordingly. The operator can select the image viewed by either of
cameras 113 and 114 for viewing on his/her monitor and,
accordingly, can utilize either image as part of the longitudinal
and angular alignment procedures.
When the camera aperature is both longitudinally and angularly
aligned with the lateral opening 108, the operator actuates the
push rod drive components located in the launcher mechanism, under
remote control, to extend the camera 114 and push rod 94 into the
lateral pipeline 109. The video image transmitted by the miniature
lateral camera 112 permits the operator to observe the interior
wall of the lateral pipeline in order to detect the presence of
leaks. After the entire lateral pipeline 109 has been inspected,
the push rod is retracted until the camera is withdrawn into the
camera aperture 112 at the launcher mechanism. The winch may then
be actuated once again to pull the entire system, via tow cable
121, until another lateral pipeline is observed in the image
provided by camera 113.
The push rod 94 is a spirally coiled rod of the type commonly used
with sewer maintenance equipment. The center of the rod is hollow
to permit the electrical cable 119 to be disposed therein and
provide electrical connections between camera 113 and circuitry
within the launcher 111.
The miniature lateral camera 114 is illustrated in FIGS. 2 and 3
and is shaped to be widest approximately at its longitudinal
midpoint while tapering in stepped increments toward both its
distal end 130 and proximal end 131. The open distal end 130 is
covered by a protective glass window 132 behind which is disposed
an infrared filter 133 in front of a lens 134. In the preferred
embodiment, lens 134 is an eight millimeter lens. A plurality of
lamps 135 are recessed at the forward or distal end 130 and are
provided to illuminate the field of view of lens 134. In the
illustrated embodiment, ten lamps 135 are provided in a circular
array with alternate lamps being directed substantially straight
ahead (i.e., parallel to the optical axis of lens 134) while the
remaining lamps are angled to project their light beams at a
divergent angle from the lens optical axis of approximately ten
degrees. In this manner, the interior walls of the lateral pipeline
can be adequately illuminated.
At the rearward or proximal end of camera 114 there is provided a
fitting 136 at which the push rod 94 is rigidly connected to the
camera. Cable 119 extends through the fitting and into the camera
body so that the individual electrical leads may be appropriately
connected to the circuitry within the camera. As noted above, this
circuitry is conventional and need not be described herein in
detail.
Referring now to FIG. 4 of the accompanying drawings, the launcher
assembly 111 includes the launcher drive unit 140 disposed within a
launcher housing. The launcher housing includes the skid members 3
at either end of the housing and a rotatable hollow cylindrical
member 2. Camera aperture 112 is defined in the hollow cylindrical
member 2 and is the termination of an arcuate passage 141 having
its other end facing axially of the cylindrical member toward the
downstream end of the launcher assembly. As illustrated in FIG. 4,
passage 141 guides push rod 94 through camera aperture 112 during
extension and retraction of the push rod and camera. A reversible
gear motor 46 is disposed within a motor housing 23 inside
cylindrical member 2 proximate the upstream end of the launcher
assembly. Motor housing 23 is provided with an opening in which an
electrical cable fitting 95 is secured to receive a power cable 96
for energizing motor 46. Cable 96 is connected to the printed
circuit board in the launcher unit 140 and extends around passage
141. Access to fitting 95 is achieved by an appropriately provided
window opening 10 disposed in cylindrical member 2. The drive shaft
of motor 46 is connected to a drive gear 43 by means of a spring
pin 98. Drive gear 43 extends from a motor mounting bulkhead 20 to
engage an internal plug gear 17 to effect rotation of the
cylindrical member 2 and bulkhead 20 relative to the skid members
3. Ball bearings 52, held in place by set screws 70, provide the
bearing arrangement at the upstream end of the assembly. The
bearing at the downstream end of the assembly is provided by four
bearing rollers 39 disposed about respective roller retainer screws
36. The retainer screws engage an annular bearing ring 19 secured
to the cylindrical member by screws 72. The bearing rollers 39 are
received in appropriate notches provided in the skid members 3 at
the downstream end of the assembly. An annular sponge rubber guard
100 is disposed radially interiorally of the bearing rollers
39.
When motor 46 is energized, the cylindrical member 2, which is
normally spaced from the interior wall of the main sewer line 110
by the skid members 3, is caused to rotate relative to the skid
members which are prevented from movement by the weight of the
assembly bearing against the interior wall of the main line 110
through the skid members.
The launcher assembly is illustrated in detail in FIGS. 4-12 to
which specific reference is now made. To side plates 8 and 9 have a
generally rectangular configuration and are disposed in spaced
parallel relation. The two plates support a magnetic counting wheel
14 and two drive wheels 13 between them. Each drive wheel, as best
illustrated in FIG. 8, is supported on a respective drive wheel
shaft 18. For each drive wheel shaft 18, there is a cylindrical
recess 147 defined in plate 8 and facing a generally cylindrical
bore 142 defined through plate 9. Appropriate bushings 41 are
disposed in recess 141 and bore 142, and rotatably support shaft
18. The shaft extends through plate 9 into a space defined by a
drive gear cover plate 7 and is secured to a drive gear 44 by means
of a spring pin 85. Gear 44 is driven by a motor drive gear 45
secured to the drive shaft of a motor 144. The gear engagement
between the motor drive gear 45 and the drive spur gear 44 is
effected within the space defined by cover plate 7 and plate 9.
Drive wheel 13 is secured about shaft 18 between plates 8 and 9 and
is rotatable with shaft 18. Each drive wheel 13 is associated with
a respective pinch roller 27 mounted on a corresponding pinch
roller shaft 26 between a pinch roller rail assembly 5 disposed
between plates 8 and 9. Push rod 94 is normally disposed between
the drive wheels 13 and their corresponding pinch rollers 27 and in
this way is propelled in either direction, depending upon the
direction in which the drive wheels are rotated. The motors 144 are
secured to plate 9 with the motor housing disposed between plates 8
and 9 and the motor drive shaft extending into the space defined
between cover plate 7 and plate 9. In fact, the motor cover tubes
15 extend through appropriate bores defined in plate 8 into the
space defined between cover plate 6 and plate 8. Cover plate 6 is
on the opposite side of the unit from cover plate 7 and defines a
space for the electronic circuitry.
The magnetic counting wheel 14 is disposed substantially at the
longitudinal center of the launcher unit 140 between the two motors
144. Magnetic counting wheel 14 is disposed entirely between plates
8 and 9 and is free wheeling about a shaft 16 extending between
opposed cylindrical recesses defined in plates 8 and 9. A
cylindrical bearing 29 is disposed between the shaft and the
interior surface of wheel 14. A plurality of magnets 37 are
recessed in the surface of wheel 14 which faces plate 8. Magnets 37
are oriented in a circular array with equal angular spacing between
them. In the particular embodiment illustrated herein, five such
magnets are disposed at the same radial distance from the center of
shaft 16 with angles of 72.degree. between successive magnets.
Appropriate bores are defined in the counting wheel 14 to receive
the magnets so that the magnets reside flush with the surface of
counting wheel 14 which faces plate 8. A Hall effect device 69 is
disposed in a suitably provided hole defined in plate 8 at a
distance from the rotational axis of magnetic counting wheel 14
which corresponds to the radial spacing of the magnets 37 from that
axis. The Hall effect device 69, which is a magnetic pick-up
device, is thus positioned to sense the passage of each magnet past
the device as the magnetic counting wheel rotates. By way of
example only, the magnetic Hall effect may be the device designated
by Serial Number UGN 3020T, manufactured by the Sprague
Manufacturing Company. Magnetic counting wheel 14 is mounted for
free rotation between plates 8 and 9 and is rotated by push rod 94
as it is extended and/or retracted by drive wheels 13 under the
control of motors 144. Thus, as the push rod 94 is translated
through the launcher unit 140, a pulse is provided by the magnetic
pick-up unit 69 for each 72.degree. of rotation of wheel 14 as
induced by the moving push rod 94. In a practical embodiment of the
invention, the radial spacing of the magnets 37 and magnetic
pick-up device 69 from the axis of wheel 14 is selected so that the
magnetic pick-up device 69 provides an output pulse after each one
half foot of length of push rod 94 is extended or retracted. These
pulses may be counted by an appropriate electronic pulse counter at
the remote control station so that the accumulated pulse count
provides a measure of the amount of push rod 94 extension and/or
retraction.
At each end of launcher unit 140 there is disposed a spring housing
member 11 between plates 8 and 9. A hole 147 is provided at the top
of spring housing 11 and includes a countersunk bore portion at its
lower end. A helical compression spring 32 is disposed in the
countersunk portion and a spring compression pin 42 is disposed
atop the spring. A yoke member 12 is located over the spring
housing, as best illustrated in FIG. 8, and has four holes at its
bottom which align with corresponding holes in the pinch roller
rail assembly 5. The yoke 12 and pinch roller rail assembly 5 are
joined by means of screws inserted through the aligned holes. A
spring compression screw 24 is inserted into hole 147 by threadedly
engaging yoke 12 through a threaded hole defined through the top of
the yoke. A nut 83 threadly engages the exposed end of the spring
compression screw 24. The spring compression screw 24 can be
adjusted against the spring force exerted by spring 32 to move the
pinch roller rail 5 closer to or further away from the drive wheels
13. In this manner, the pinch rollers 27, engaged in the pinch
roller rail 5, can be spring loaded against the push rod 24 with
the desired amount of force.
The space between side plate 8 and cover plate 6 contains the
electronics portion of the launcher unit 140. A printed circuit
board 58 is secured to cover plate 6 by means of screws 78. Wires
from cables 119 and 126 are delivered to the printed circuit board,
the motors 144 and motor 46. The electrical circuitry associated
with the launcher unit 140 is illustrated in schematic form in FIG.
13 described in the following paragraphs.
The lefthand side of FIG. 13 represents electrical signals
connecting the remote control operator station with the launcher
unit 140, the lateral camera 114 and the main camera 113. The
EXTEND/RETRACT control energizes both motors 140 simultaneously.
The voltage provided by this signal can be polarized positive and
negative, alternatively, to effect the desired rotational direction
in the motor. The ROTATE signal can also have both polarities and
thereby drives the rotate motor 46 in either of two directions.
Thus, rotation of cylindrical member 2 relative to skid members 3
can be in either direction.
An unregulated 15 volt power line, with positive polarity, is
delivered through a diode D1 to a voltage regulator unit 150.
External connections to the voltage regulator include capacitors
C1, C2 and resistors R3 and R4. Voltage regulator 150 provides a
regulated 12 volt d.c. line for use in the circuit. The unregulated
voltage, at the output of diode D1, is applied to the main line
camera 113 as the primary operating power for that camera.
The magnetic pick-up 69 receives the regulated 12 volt power
through a resistor R7 and supplies its output pulses, designated
FOOTAGE pulses, through a resistor R6. As noted above, these pulses
may be counted at the remote control station as a measure of the
length of push rod 94 which has been extended or retracted.
An NPN transistor Q1 receives a Lateral Select signal at its base
through resistor R1. A resistor R2 is connected between the base
and emitter electrodes with the emitter side of the transistor
being connected to ground. The collector of transistor Q1 is
connected through resistor R5 to one side of a relay coil K1. The
other side of relay coil K1 is connected to the +12 volt regulated
voltage supply line. The arm of the contact for relay K1 is
connected to the SELECTED VIDEO signal line which provides a video
signal from the system to the remote control station. The state of
relay K1 determines whether the video signal from the lateral
camera or the video signal from the main camera is transmitted back
to the remote control station as the selected video signal. When
the voltage on the lateral select line is below the switching
threshold of transistor Q1, relay K1 is un-energized, permitting
the main camera video signal to be transmitted to the remote
control station. When the lateral select signal, as controlled from
the remote control station, is more positive than the switching
threshold for transistor Q1, relay K1 is energized and switches the
lateral camera video signal onto the selected video line. The
LATERAL SELECT signal is also utilized as the energizing signal for
the lights 135 at the lateral camera 114. Thus, upon energization
of the lights at the lateral camera, the video signal is
automatically switched from the main camera to the lateral
camera.
Also illustrated in FIG. 13 are the high voltage light energizing
signals for the main camera. These signals pass through the
launcher unit 140 and onto the main camera 113 via cable 117.
The invention as described has been utilized to propel the lateral
camera into a building service lateral sewer pipe as small as 4
inches in diameter. The only limitation on the minimum size
pipeline is the corresponding dimension of the lateral camera. It
is contemplated that the invention has applicability for any size
lateral pipeline if a camera can be made small enough to traverse
that line. In any event, the camera is pushed through the lateral
line by actuating both drive motors 144 from the remote control
station in the same direction. Motor gears 45 then drive the gears
for drive wheels 13. The drive wheels are thusly driven in the same
direction to propell push rod 94 and camera 114 into the lateral
pipeline 109. Magnetic counting wheel 14 is rotated by the push rod
94 as the push rod is translated through the launcher unit 140.
Rotation of magnetic counting wheel 14 causes the magnetic pick-up
unit 69 to provide a pulse as each magnetic 37 in wheel 14 passes
the magnetic pick-up unit. When the lights 135 on the lateral
camera 114 are energized, the video signal received at the remote
control station is switched from the main camera video to the
lateral camera video. After the lateral line 109 has been inspected
via the lateral camera 114, the direction of motors 144 may be
reversed by reversing the polarity of the voltage applied thereto
from the remote control station. This serves to drive the drive
wheels 13 in the opposite direction to retract the push rod 94 from
the lateral line 109.
From the foregoing description it will be clear that we have
provided a unique method and apparatus for permitting inspection of
building service lateral lines from a main sewer line without
requiring excavation. The location of any leaks in the lateral line
may be detected and precisely located by observation through a
closed circuit television camera. This is much more advantageous
than simply detecting the presence of a leak, using pressure
transducers, without determining the precise location of that leak.
Importantly, the electrical connections required for the lateral
camera can be enclosed in the push rod 94 which moves the camera in
and out of the lateral line.
While we have described and illustrated a specific embodiment of
our invention, it will be clear that variations of the details of
construction which are specifically illustrated and described
herein may be resorted to without departing from the true spirit
and scope of the invention as described in the appended claims.
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