Patent US4196783A successfully refreshed from Google Patents.
US4196783A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for boring
Assignee: LOFS VERKSTADS AB
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Filing: 1978-07-11
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Granted: 1980-04-08
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Expires: 1998-07-11
Abstract
Abstract Boring apparatus comprising a tubular casing containing a cylindrical body adapted for being driven by a boring rod and a filter body adjacent the cylindrical body. A boring tool is mounted outside the tubular casing at the end of the filter body. The filter body has a cross-section of polygon shape with axially extending edges in contact with the inner surface of the tubular casing to define clearance spaces between the inner surface of the tubular casing and the outer surface of the filter body. The cylindrical body has axial grooves extending to the clearance spaces for passage of boring particles. The cylindrical body can also be provided with annular grooves. Preferably, the cylindrical body and filter body are constituted as a single unit.
Inventors
- 👤 Stig U. Lof
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:57
CPC Classifications
E; E21; E21B; E21B17/00; E21B17/10; E21B17/1078; E21B21/00; E21B21/002; E21B7/00; E21B7/20
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
103 words
Boring apparatus comprising a tubular casing, a cylindrical body in said casing adapted for being driven by a boring rod, a filter body disposed in said casing adjacent said cylindrical body and a boring tool mounted outside said tubular casing after said filter body, said filter body having a polygonal multi-sided cross-section with axially extending edges in contact with the inner surface of the tubular casing to define clearance spaces between the inner surface of the tubular casing and the outer surface of the filter body, said filter body and tubular casing constituting a slide bearing and centering means for the boring tool.
Claim 2
Dependent Claim
103 words
Boring apparatus comprising a tubular casing, a cylindrical body in said casing adapted for being driven by a boring rod, a filter body disposed in said casing adjacent said cylindrical body and a boring tool mounted outside said tubular casing after said filter body, said filter body having a polygonal multi-sided cross-section with axially extending edges in contact with the inner surface of the tubular casing to define clearance spaces between the inner surface of the tubular casing and the outer surface of the filter body, said filter body and tubular casing constituting a slide bearing and centering means for the boring tool.
Claim 3
Dependent Claim
16 words
Boring apparatus as claimed in claim 1 wherein said edges of the filter body are bow-shaped.
Claim 4
Dependent Claim
19 words
Boring apparatus as claimed in claim 1 wherein said filter body is provided with at least one peripheral groove.
Claim 5
Dependent Claim
26 words
Boring apparatus as claimed in claim 3 wherein said filter body has a surface remote from said boring tool which is united with said cylindrical body.
Claim 6
Dependent Claim
30 words
Boring apparatus as claimed in claim 4 wherein said cylindrical body has a plurality of axial grooves for passage of boring particles, said axial grooves extending to said clearance spaces.
Claim 7
Dependent Claim
17 words
Boring apparatus as claimed in claim 5 wherein said cylindrical body has a plurality of annular grooves.
Claim 8
Dependent Claim
20 words
Boring apparatus as claimed in claim 5 wherein said filter body and cylindrical body are constituted as a single unit.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-04-08 | 1983-10-08 | 1984-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-04-08 | 1987-10-08 | 1988-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-04-08 | 1991-10-08 | 1992-04-08 | $7700.00 | Window Closed / Lapsed |