Patent US3701389A successfully refreshed from Google Patents.
US3701389A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wire line core drilling apparatus
Assignee: Craelius AB
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Filing: 1971-04-23
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Granted: 1972-10-31
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Expires: 1991-04-23
Abstract
Abstract A wire line core drilling apparatus comprising a tubular drill stem, an annular drill bit mounted at the forward end of the drill stem and an inner core tube assembly, the latter of which is provided with at least one latch dog for being lockable against longitudinal displacement relative to the drill stem and for being connectable to a retrieving device introduced in the drill stem.
Inventors
- 👤 Gunnar Kristoffer Egnelov
- 👤 Sune Vilhelm Eriksson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:34
CPC Classifications
E; E21; E21B; E21B25/00; E21B25/02; E21B23/00; E21B23/02
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
200 words
A wire line core drilling apparatus comprising: a tubular drill stem having a forward facing and a backward facing shoulder on the inner wall thereof; an annular drill bit mounted at the forward end of the drill stem; an inner core tube assembly; and connecting means for selectively connecting said inner core tube assembly to a retrieving device and for selectively locking said inner core tube assembly relative to the drill stem, said connecting means including at least one latch dog pivotably mounted on a transverse stub axle, said latch dog having a first locking portion for cooperation with said forward facing shoulder on the drill stem inner wall for preventing backward displacement of the inner core tube assembly relative to the drill stem, a second locking portion for cooperation with said backward facing shoulder on the drill stem inner wall for preventing forward displacement of the inner core tube assembly relative to the drill stem, said first and second locking portions being disposed at opposite sides of said stub axle, and a gripping jaw for cooperation with a coupling means on a retrieving device, by means of which the inner core tube assembly is manouverable within the drill stem.
Claim 2
Dependent Claim
200 words
A wire line core drilling apparatus comprising: a tubular drill stem having a forward facing and a backward facing shoulder on the inner wall thereof; an annular drill bit mounted at the forward end of the drill stem; an inner core tube assembly; and connecting means for selectively connecting said inner core tube assembly to a retrieving device and for selectively locking said inner core tube assembly relative to the drill stem, said connecting means including at least one latch dog pivotably mounted on a transverse stub axle, said latch dog having a first locking portion for cooperation with said forward facing shoulder on the drill stem inner wall for preventing backward displacement of the inner core tube assembly relative to the drill stem, a second locking portion for cooperation with said backward facing shoulder on the drill stem inner wall for preventing forward displacement of the inner core tube assembly relative to the drill stem, said first and second locking portions being disposed at opposite sides of said stub axle, and a gripping jaw for cooperation with a coupling means on a retrieving device, by means of which the inner core tube assembly is manouverable within the drill stem.
Claim 3
Dependent Claim
46 words
A core drilling apparatus according to claim 1 including two latch dogs which are identical but reversed mounted relative to each other on the stub axle, said latch dogs being arranged so as to cooperate with the shoulders of the drill stem at diametrically opposite points.
Claim 4
Dependent Claim
37 words
A core drilling apparatus according to claim 1 wherein said at least one latch dog is biased toward inner dogs being arranged so as to cooperate with the shoulders of the drill stem at diametrically opposite points.
Claim 5
Dependent Claim
46 words
A core drilling apparatus according to claim 3 including two latch dogs which are identical but reversed mounted relative to each other on the stub axle, said latch dogs being arranged so as to cooperate with the shoulders of the drill stem at diametrically opposite points.
Claim 6
Dependent Claim
37 words
A core drilling apparatus according to claim 1 wherein said at least one latch dog has two rearwardly extending arms one of which comprises said first locking portion and the other of which comprises said gripping jaw.
Claim 7
Dependent Claim
68 words
A core drilling apparatus according to claim 5 including two latch dogs which are identical but reversed mounted relative to each other on the stub axle, said latch core tube assembly locking positions, the latch dog being pivoted about said stub axle such that the inner core tube assembly is unlocked relative to the drill stem when said retrieving device is brought into cooperation with the gripping jaws.
Claim 8
Dependent Claim
41 words
A core drilling apparatus according to claim 1 further comprising said retrieving device and wherein said retrieving device coupling means includes a rod having a spear-shaped forward end selectively engagable with said gripping jaw of said at least one latch dog.
Claim 9
Dependent Claim
44 words
A core drilling apparatus according to claim 7 wherein said retrieving device coupling means further includes an axially shiftable sleeve mounted over said rod for selectively engaging said at least one latch dog to disengage said rod from said at least one latch dog.
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) | 1975-10-31 | 1976-05-01 | 1976-10-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-31 | 1980-05-01 | 1980-10-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-31 | 1984-05-01 | 1984-10-31 | $7700.00 | Window Closed / Lapsed |