US4113818A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Drain pipe method
Assignee: Agro-Drip Inc
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Filing: 1977-03-02
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Granted: 1978-09-12
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Expires: 1997-03-02
Abstract
Abstract A drain pipe of corrugated form comprising corrugations of uniform inner diameter having axially in line alternating drain holes and outward protrusions in the corrugation troughs. The drain holes are cut by a stationary knife which engages the troughs of normally formed corrugations but which are set below the level of the protrusions, thus cutting a drain hole only in alternate corrugations. Preferably drain holes and protrusions are also staggered about the circumference of each corrugation trough.
Inventors
- 👤 Hubert Drossbach
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 10:43
CPC Classifications
E; E02; E02B; E02B11/00; E02B11/005; B; B26; B26F; B26F1/00; B26F1/0015; B26F1/0053
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
134 words
The method of producing corrugated pipe having water inlet orifices in the troughs of said corrugations characterized by forming corrugations of uniform inner diameter in the wall of said pipe and forming outwardly extending protrusions in said troughs along a line extending axially along said pipe by providing a forming mold having corrugations with interruptions corresponding to said protrusions and deforming said pipe into said corrugations and said interruptions, said protrusions spaced along said line in troughs alternating with other troughs having no protrusions along said line, moving said pipe linearly relative to a cutter arranged inwardly of said protrusions and outwardly of said troughs, and cutting said troughs by said relative linear motion of said pipe and cutter to form said orifices in said troughs in line with said protrusions which remain uncut.
Claim 2
Independent Claim
134 words
The method of producing corrugated pipe having water inlet orifices in the troughs of said corrugations characterized by forming corrugations of uniform inner diameter in the wall of said pipe and forming outwardly extending protrusions in said troughs along a line extending axially along said pipe by providing a forming mold having corrugations with interruptions corresponding to said protrusions and deforming said pipe into said corrugations and said interruptions, said protrusions spaced along said line in troughs alternating with other troughs having no protrusions along said line, moving said pipe linearly relative to a cutter arranged inwardly of said protrusions and outwardly of said troughs, and cutting said troughs by said relative linear motion of said pipe and cutter to form said orifices in said troughs in line with said protrusions which remain uncut.
Claim 3
Dependent Claim
50 words
The method claimed in claim 1 characterized in forming said protrusions along a plurality of axially extending lines in troughs alternating with other troughs having no protrusions along said line, providing a said cutter along each said line and cutting said troughs to form said orifices along each said line.
Claim 4
Dependent Claim
31 words
The method claimed in claim 2 further characterized by providing said protrusions along each said line in alternate troughs and forming protrusions at alternate lines about the circumference of said pipe.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-09-11 | 1982-03-13 | 1982-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-09-11 | 1986-03-13 | 1986-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-09-11 | 1990-03-13 | 1990-09-12 | $7700.00 | Window Closed / Lapsed |