Patent US3897073A successfully refreshed from Google Patents.
US3897073A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Joint of underground pipe
Assignee: Madison Management Group Inc
•
Filing: 1974-11-04
•
Granted: 1975-07-29
•
Expires: 1994-11-04
Abstract
Abstract A method for joining nonmetallic pipes underground, with the pipes having mating pairs of bells and spigots, by fitting between mating spigots and bells dry bands of an open celled material (preferably reticulated polyurethane foam) having a dry hydratable cement (preferably portland cement) impregnated therein and engaging each of the bands between one of the bells and its mating spigot. On wetting of the bands, the cement hydrates thereby hardening.
Inventors
- 👤 Harold V Swanson
- 👤 Robert E Bald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 12:44
CPC Classifications
F; F16; F16L; F16L21/00; F16L21/02; F16L21/025; F16L13/00; F16L13/10; F16L13/11; F16L13/113
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
80 words
A JOINT BETWEEN FIRST AND SECOND CONTINUOUS SUCESSIVE LENGTHS OF PIPE MADE OF A NONMETALLIC EARTHEN MATERIAL, WHEREIN A BELL FORMED ON AN END OF THE FIRST LENGTH IS ENGAGED BY A SPIGOT FORMED ON AN END OF A SECOND LENGTH THE JOINT CHARACTERIZED BY A DISTORTABLE BAND OF A CULLULAR WATER INVADABLE MATERIAL IMPREGNATED WITH A DRY HYDRATABLE CEMENT WHICH IS REACTIVE WITH WATER TO HYDRATE THEREBY FORMING A HARD WATER IMPERVIOUS SUBSTANCE THE BAND POSITIONED BETWEEN THE SPIGOT
Claim 2
Dependent Claim
80 words
A JOINT BETWEEN FIRST AND SECOND CONTINUOUS SUCESSIVE LENGTHS OF PIPE MADE OF A NONMETALLIC EARTHEN MATERIAL, WHEREIN A BELL FORMED ON AN END OF THE FIRST LENGTH IS ENGAGED BY A SPIGOT FORMED ON AN END OF A SECOND LENGTH THE JOINT CHARACTERIZED BY A DISTORTABLE BAND OF A CULLULAR WATER INVADABLE MATERIAL IMPREGNATED WITH A DRY HYDRATABLE CEMENT WHICH IS REACTIVE WITH WATER TO HYDRATE THEREBY FORMING A HARD WATER IMPERVIOUS SUBSTANCE THE BAND POSITIONED BETWEEN THE SPIGOT
Claim 3
Dependent Claim
13 words
The joint of claim 1 with the band arranged annularly around the spigot.
Claim 4
Dependent Claim
12 words
The joint of claim 2 with the band a reticulated polyurethane foam.
Claim 5
Dependent Claim
11 words
The joint of claim 1 with the cement being portland cement.
Claim 6
Dependent Claim
12 words
The joint of claim 1 with a water-permeable sheath about the band.
Claim 7
Dependent Claim
11 words
The joint of claim 5 with the cement being portland cement.
Claim 8
Dependent Claim
12 words
The joint of claim 5 with the sheath being nonwoven polyester fabric.
Claim 9
Dependent Claim
13 words
The joint of claim 1 with the band arranged annularly in the bell.
Claim 10
Dependent Claim
12 words
The joint of claim 8 with the band a reticulated polyurethane foam.
Claim 11
Dependent Claim
11 words
The joint of claim 8 with the cement being portland cement.
Claim 12
Dependent Claim
12 words
The joint of claim 8 with a water-permeable sheath about the band.
Claim 13
Dependent Claim
11 words
The joint of claim 11 with the cement being portland cement.
Claim 14
Dependent Claim
12 words
The joint of claim 11 with the sheath being nonwoven polyester fabric.
References Cited (Backward Citations)
US1662603A
Cited
US2051557A
Cited
US2140672A
Cited
US2309658A
Cited
US2662555A
Cited
US3095619A
Cited
US3729205A
Cited
US3771175A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-07-28 | 1979-01-27 | 1979-07-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-28 | 1983-01-27 | 1983-07-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-28 | 1987-01-27 | 1987-07-29 | $7700.00 | Window Closed / Lapsed |