Patent US3685237A successfully refreshed from Google Patents.
US3685237A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Property boundary marker
Assignee: Individual
•
Filing: 1970-02-24
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Granted: 1972-08-22
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Expires: 1990-02-24
Abstract
Abstract A boundary marker designed to be buried in the ground and constructed with a maximum surface area so as to afford maximum resistance to movement in any direction. The marker is cast from iron in the shape of alternate orthogonal, thin plates so that external forces fracture the plates of the marker rather than move it. The marker is adjustable in length and cast from an iron which is high in cementite so that the marker can be magnetized for easy location.
Inventors
- 👤 John David Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 00:21
CPC Classifications
G; G01; G01C; G01C15/00; G01C15/02; G01C15/06
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
105 words
A property boundary marker adapted to be buried comprising a cast iron column shaped so as to have along its length a plurality of weak zones which comprise preferred fracture points in which the weak zones in said column comprise first, second, and third sets of fracturable flat plates, each said plate having a large surface area, said first flat plates alternate with said second flat plates in an end to end nonaligned angular relationship and in which each adjoining first and second flat plates are separated by a third flat plate disposed in a plane generally orthogonal to said first and second flat plates.
Claim 2
Dependent Claim
105 words
A property boundary marker adapted to be buried comprising a cast iron column shaped so as to have along its length a plurality of weak zones which comprise preferred fracture points in which the weak zones in said column comprise first, second, and third sets of fracturable flat plates, each said plate having a large surface area, said first flat plates alternate with said second flat plates in an end to end nonaligned angular relationship and in which each adjoining first and second flat plates are separated by a third flat plate disposed in a plane generally orthogonal to said first and second flat plates.
Claim 3
Dependent Claim
35 words
The apparatus of claim 1 in which said first, second, and third sets of flat plates are disposed in three generally orthogonal planes respectively so as to present a maximum surface area in all directions.
Claim 4
Dependent Claim
20 words
The apparatus of claim 2 including gussets on said plates operable to further define and localize said preferred fracture points.
Claim 5
Dependent Claim
27 words
The apparatus of claim 2 including reinforcing ribs on said first and second plates running generally parallel to and contiguous to the central axis of said column.
Claim 6
Dependent Claim
15 words
The apparatus of claim 4 in which said third set of plates are generally cross-shaped.
Claim 7
Dependent Claim
29 words
The apparatus of claim 5 in which said column comprises multiple portions, each portion terminated with a base plate adapted to connect to the base plate of another portion.
Claim 8
Dependent Claim
29 words
The apparatus of claim 6 including spacer blocks adapted to connect to the end of one of said multiple portions so as to vary the length of said column.
Claim 9
Dependent Claim
29 words
The apparatus of claim 7 in which said spacer blocks are designed to rust solidly to the marker so as to resist loosening until removed with an impact wrench.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-22 | 1976-02-21 | 1976-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-22 | 1980-02-21 | 1980-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-22 | 1984-02-21 | 1984-08-22 | $7700.00 | Window Closed / Lapsed |