US3874926A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for injecting foam into a pipe
Assignee: Airrigation Engineering Co Inc
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Filing: 1973-07-12
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Granted: 1975-04-01
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Expires: 1993-07-12
Abstract
Abstract A method and apparatus for injecting foam into a pipe, such as a sewer. For example, the injection may be used to kill root growths in sewers. A foam-conducting flexible tube has a terminal portion at its outlet having a through conduit for passage of the foam and a double wall therearound that provides an inflatable portion which, when inflated, can be used to plug the sewer to prevent backflow of foam. A flexible air conduit, which may be inside the main tube, enables the application of air pressure after insertion of the tube to a desired location to inflate the outer plugging wall. Foam is then delivered under pressure to go through the tube and its terminal portion and out beyond the plug portion and so to fill the sewer quickly with a foam which contains material for attacking the roots.
Inventors
- 👤 Frederick F Horne
- 👤 Gerald G Vanderlans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 02:40
CPC Classifications
B; B08; B08B; B08B9/00; B08B9/02; B08B9/027; B08B9/032; B08B9/0321; B08B9/0322; A; A01; A01N; A01N25/00; A01N25/16; E; E03; E03F; E03F9/00; Y; Y10; Y10S; Y10S261/00; Y10S261/26
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
127 words
Apparatus for injecting foam into a pipeline, including in combination: a foam-conducting flexible tube having an inlet and a terminal portion having a through outlet for the foam and a tube wall having therearound an inflatable plugging portion, which can be enlarged by inflation to bear against the wall of the pipe and prevent the foam from flowing back between said tube and said pipe, a flexible air conduit much smaller in diameter than said tube and having an inlet and an outlet connected to said inflatable plugging portion, means for delivering compressed air to the inlet of said air conduit for inflating and retaining inflation of said plugging portion, and means for producing foam and delivering it under pressure to said inlet of said foam-conducting tube.
Claim 2
Dependent Claim
127 words
Apparatus for injecting foam into a pipeline, including in combination: a foam-conducting flexible tube having an inlet and a terminal portion having a through outlet for the foam and a tube wall having therearound an inflatable plugging portion, which can be enlarged by inflation to bear against the wall of the pipe and prevent the foam from flowing back between said tube and said pipe, a flexible air conduit much smaller in diameter than said tube and having an inlet and an outlet connected to said inflatable plugging portion, means for delivering compressed air to the inlet of said air conduit for inflating and retaining inflation of said plugging portion, and means for producing foam and delivering it under pressure to said inlet of said foam-conducting tube.
Claim 3
Dependent Claim
22 words
The apparatus of claim 1 wherein said flexible air conduit lies inside said foam-conducting tube for at least most of its length.
Claim 4
Dependent Claim
22 words
The apparatus of claim 1 wherein said flexible air conduit passes through the wall of said foam-conducting tube adjacent to said inlet.
Claim 5
Dependent Claim
146 words
Apparatus for injecting foam into a pipe, including in combination: a foam-conducting flexible tube having an inlet and an outlet, a terminal tube connected to said outlet of said foam-conducting tube and having a stiff-walled through conduit for the foam and a tube wall having therearound an inflatable plugging portion including a flexible wall which can be enlarged by inflation to bear against the wall of the pipeline and prevent the foam from flowing back between the tubes and the pipeline, a flexible air conduit much smaller in diameter than said tubes and having a terminal end connected to said plugging portion and substantially the same length as said flexible tube, means for delivering compressed air to said air conduit for inflating and retaining inflation of said plugging portion, and means for producing foam and delivering it under pressure to said inlet of said foam-conducting tube.
Claim 6
Dependent Claim
146 words
Apparatus for injecting foam into a pipe, including in combination: a foam-conducting flexible tube having an inlet and an outlet, a terminal tube connected to said outlet of said foam-conducting tube and having a stiff-walled through conduit for the foam and a tube wall having therearound an inflatable plugging portion including a flexible wall which can be enlarged by inflation to bear against the wall of the pipeline and prevent the foam from flowing back between the tubes and the pipeline, a flexible air conduit much smaller in diameter than said tubes and having a terminal end connected to said plugging portion and substantially the same length as said flexible tube, means for delivering compressed air to said air conduit for inflating and retaining inflation of said plugging portion, and means for producing foam and delivering it under pressure to said inlet of said foam-conducting tube.
Claim 7
Dependent Claim
18 words
The apparatus of claim 4 wherein said flexible wall is vulcanized at each end to said stiff-walled conduit.
Claim 8
Dependent Claim
15 words
The apparatus of claim 4 wherein said stiff-walled conduit is reinforced to increase its stiffness.
Claim 9
Dependent Claim
22 words
The apparatus of claim 4 wherein said flexible air conduit lies inside said foam-conducting tube for at least most of its length.
Claim 10
Dependent Claim
21 words
The apparatus of claim 4 wherein said flexible air conduit passes through the wall of said foam-conducting tube adjacent said inlet.
Claim 11
Dependent Claim
26 words
The apparatus of claim 4 wherein said means for producing foam comprises a foam-generating pump that whips air into a suitable liquid to form said foam.
Claim 12
Independent Claim
114 words
A METHOD FOR INJECTING FOAM INTO A PIPE COMPRISING: INSERTING INTO SAID PIPE A FOAM-CONDUCTING FLEXIBLE TUBE HAVING AN INLET AND AN OUTLET AT A TERMINAL PORTION WHERE THE TUBE WALL HAS AN OUTLET SURROUNDED BY AN INFLATABLE PLUGGING PORTION, WHICH CAN BE ENLARGED BY INFLATION TO BEAR AGAINST THE WALL OF THE PIPELINE SO AS TO PREVENT FOAM FROM FLOWING BACK BETWEEN THE TUBES AND THE PIPELINE, SENDING AIR UNDER PRESSURE TO SAID PLUGGING PORTION TO INFLATE IT AND PLUG SAID PIPE RETAINING SAID INFLATION DURING FOAM INJECTION, GENERATING SAID FOAM EXTERIOR TO SAID PIPE, DELIVERING SAID FOAM UNDER PRESSURE TO SAID INLET OF SAID FOAM-CONDUCTING TUBE AND THEN THROUGH TO SAID OUTLET.
Claim 13
Independent Claim
114 words
A METHOD FOR INJECTING FOAM INTO A PIPE COMPRISING: INSERTING INTO SAID PIPE A FOAM-CONDUCTING FLEXIBLE TUBE HAVING AN INLET AND AN OUTLET AT A TERMINAL PORTION WHERE THE TUBE WALL HAS AN OUTLET SURROUNDED BY AN INFLATABLE PLUGGING PORTION, WHICH CAN BE ENLARGED BY INFLATION TO BEAR AGAINST THE WALL OF THE PIPELINE SO AS TO PREVENT FOAM FROM FLOWING BACK BETWEEN THE TUBES AND THE PIPELINE, SENDING AIR UNDER PRESSURE TO SAID PLUGGING PORTION TO INFLATE IT AND PLUG SAID PIPE RETAINING SAID INFLATION DURING FOAM INJECTION, GENERATING SAID FOAM EXTERIOR TO SAID PIPE, DELIVERING SAID FOAM UNDER PRESSURE TO SAID INLET OF SAID FOAM-CONDUCTING TUBE AND THEN THROUGH TO SAID OUTLET.
References Cited (Backward Citations)
US2273984A
Cited
US3037887A
Cited
US3075535A
Cited
US3337195A
Cited
US3637021A
Cited
US3741807A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-31 | 1978-09-30 | 1979-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-31 | 1982-09-30 | 1983-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-31 | 1986-09-30 | 1987-04-01 | $7700.00 | Window Closed / Lapsed |