US4182581A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pipe for underdraining
Assignee: Mitsui Chemicals Inc
•
Filing: 1978-03-17
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Granted: 1980-01-08
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Expires: 1998-03-17
Abstract
Abstract A pipe for underdrainage comprises (1) a liquid-collecting pipe; (2) a plurality of discontinuous protrusions on the outer surface of the liquid-collecting pipe; (3) a filter layer capable of passing liquid while substantially excluding solids, the filter layer being disposed around the liquid-collecting pipe and contacting the top portions of the protrusions; and (4) a liquid-conducting way composed of a space communicating both in the longitudinal direction and in the peripheral direction of the liquid collecting pipe and defined by the protrusions, the outer surface of the liquid-collecting pipe and the inner surface of the filter layer.
Inventors
- 👤 Yoshio Uehara
- 👤 Minoru Inaba
- 👤 Noriyuki Ishii
- 👤 Yoshihisa Kusumi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 07:45
CPC Classifications
E; E02; E02B; E02B11/00; E02B11/005
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
124 words
A pipe for underdrainage which comprises: (1) a liquid collecting pipe; (2) a plurality of discontinuous protrusions on the outer surface of the liquid collecting pipe; (3) a plurality of through-holes on the outer surface of the liquid collecting pipe and between the discontinuous protrusions; (4) a filter layer which permits the passage of liquids while substantially excluding solids, the filter layer being disposed around the liquid collecting pipe and contacting the top portions of the protrusions; and (5) a liquid conducting way composed of a space communicating both in the longitudinal direction and in the peripheral direction of the liquid collecting pipe and defined by the protrusions, the outer surface of the liquid collecting pipe and the inner surface of the filter layer.
Claim 2
Dependent Claim
124 words
A pipe for underdrainage which comprises: (1) a liquid collecting pipe; (2) a plurality of discontinuous protrusions on the outer surface of the liquid collecting pipe; (3) a plurality of through-holes on the outer surface of the liquid collecting pipe and between the discontinuous protrusions; (4) a filter layer which permits the passage of liquids while substantially excluding solids, the filter layer being disposed around the liquid collecting pipe and contacting the top portions of the protrusions; and (5) a liquid conducting way composed of a space communicating both in the longitudinal direction and in the peripheral direction of the liquid collecting pipe and defined by the protrusions, the outer surface of the liquid collecting pipe and the inner surface of the filter layer.
Claim 3
Dependent Claim
17 words
A pipe for underdrainage according to claim 1 in which the liquid collecting pipe has small through-holes.
Claim 4
Dependent Claim
14 words
A pipe for underdrainage according to claim 1 in which the protrusions are button-like.
Claim 5
Dependent Claim
23 words
A pipe for underdrainage according to claim 1 in which the protrusions discontinuously extend in the longitudinal direction as to the liquid-collecting pipe.
Claim 6
Dependent Claim
23 words
A pipe for underdrainage according to claim 1 in which the protrusion discontinuously extend in the peripheral direction as to the liquid-collecting pipe.
Claim 7
Dependent Claim
15 words
A pipe for underdrainage according to claim 1 in which the protrusions discontinuously extend spirally.
Claim 8
Dependent Claim
14 words
A pipe for underdrainage according to claim 1 in which the protrusions are hollow.
Claim 9
Dependent Claim
40 words
A pipe for underdrainage according to claim 1 in which the protrusions are hollow and discontinuously extend in the peripheral direction as to the liquid collecting pipe and the filter layer is composed of a foamed sheet having small through-holes.
References Cited (Backward Citations)
US2433300A
Cited
FR1458179A
Cited
US3566607A
Cited
US3830373A
Cited
US3753352A
Cited
DE2343866A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-01-07 | 1983-07-09 | 1984-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-01-07 | 1987-07-09 | 1988-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-01-07 | 1991-07-09 | 1992-01-08 | $7700.00 | Window Closed / Lapsed |