Patent US3954058A successfully refreshed from Google Patents.
US3954058A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coal mine shooting plug
Assignee: Individual
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Filing: 1974-05-03
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Granted: 1976-05-04
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Expires: 1994-05-03
Abstract
Abstract A recoverable plug for the blasting hole of a mine. A steel ball is enclosed within one hollowed-out portion of the plug, and sealed therein, so that the plug may be magnetically recovered after the blasting has been completed; or later, when the mined material is treated with a fluid such as water. The hollowed-out portion is further charged with compressed air, or similar fluid, to assist in absorbing the shock when the blast occurs, with the hollowed-out-portion also making the plug bouyant when it passes through a washing or similar liquid. Suitable expansion means is provided to "seat" the plug in a blasting hole.
Inventors
- 👤 Barney Sanders
- 👤 Wetzel R. Sanders
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:30
CPC Classifications
F; F42; F42D; F42D1/00; F42D1/08; F42D1/18
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
84 words
A multi-part plug including one part having a chamber with a steel ball sealed therewithin, a middle part secured to said first part and receiving a third part to seat the plug in a drilled hole, said chambered part also having a concussion cup facing an explosive charge, the middle part having a nose on one end, sealed to said chambered part, said third part including wedge means fitting into slit portions of said middle part to fix the plug within a drilled hole.
Claim 2
Dependent Claim
84 words
A multi-part plug including one part having a chamber with a steel ball sealed therewithin, a middle part secured to said first part and receiving a third part to seat the plug in a drilled hole, said chambered part also having a concussion cup facing an explosive charge, the middle part having a nose on one end, sealed to said chambered part, said third part including wedge means fitting into slit portions of said middle part to fix the plug within a drilled hole.
Claim 3
Dependent Claim
23 words
The plug of claim 1 wherein the sealed chamber is further coated interiorly with a self-sealing rubber and then pressurized above atmospheric pressure.
Claim 4
Dependent Claim
44 words
The plug of claim 2 wherein said middle part is quartered by said slit portions, said wedge means including a conically-shaped expanding part having a hemispherical tip inserted between said slit portions, a rubber band in a groove circumscribing said middle and third parts.
Claim 5
Dependent Claim
115 words
A recoverable blasting plug for use in a blasting hole to form a closure therefor outwardly of a blasting charge, said plug comprising an elongated body of non-metallic, expandable material, one end of the body having a generally hollow semi-spherical concussion cup end disposed in facing relation to the blasting charge, the other end of said body including means expandable into engagement with the blast hole, said body including a sealed chamber intermediate the ends thereof defined by a thin, resilient peripheral wall for radial expansion into sealing engagement with the blast hole when the blasting charge is detonated and the concussion end and adjacent portions of the body are forced longitudinally toward the chamber.
Claim 6
Dependent Claim
115 words
A recoverable blasting plug for use in a blasting hole to form a closure therefor outwardly of a blasting charge, said plug comprising an elongated body of non-metallic, expandable material, one end of the body having a generally hollow semi-spherical concussion cup end disposed in facing relation to the blasting charge, the other end of said body including means expandable into engagement with the blast hole, said body including a sealed chamber intermediate the ends thereof defined by a thin, resilient peripheral wall for radial expansion into sealing engagement with the blast hole when the blasting charge is detonated and the concussion end and adjacent portions of the body are forced longitudinally toward the chamber.
Claim 7
Dependent Claim
48 words
The structure as defined in claim 4 wherein said chamber includes a ferrous member therein to enable recovery of the plug by magnetic means, said body of non-metallic material completely surrounding said ferrous member to prevent contact between the ferrous member and the wall of the blasting hole.
Claim 8
Dependent Claim
37 words
The structure as defined in claim 4 wherein said chamber includes a lining of self-sealing material on the inner surface thereof to enable pressurizing the chamber by inserting an inflating needle through the body into the chamber.
Claim 9
Dependent Claim
119 words
The structure as defined in claim 4 wherein said expandable means includes a conical recess in the end of the body, a conical wedge received in said recess, said body having a plurality of longitudinal slits in the periphery of the recess to enable radial expansion when the wedge is driven into the recess, resilient means encircling the exterior of the end of the body having the slits therein to bias the end of the body radially inwardly, said wedge having an enlargement on the inner end retained in an enlarged cavity at the inner end of the recess, said enlargement being longitudinally movable in the cavity to enable expansion of the portions of the body between the slits.
Claim 10
Dependent Claim
77 words
The structure as defined in claim 7 wherein said chamber includes a ferrous member therein to enable recovery of the plug by magnetic means, said body of non-metallic material completely surrounding said ferrous member to prevent contact between the ferrous member and the wall of the blasting hole, said chamber including a lining of self-sealing material on the inner surface thereof to enable presurizing the chamber by inserting an inflating needle through the body into the chamber.
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) | 1979-05-04 | 1979-11-03 | 1980-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-05-04 | 1983-11-03 | 1984-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-05-04 | 1987-11-03 | 1988-05-04 | $7700.00 | Window Closed / Lapsed |