Patent US4134527A successfully refreshed from Google Patents.
US4134527A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Powder charge operated apparatus
Assignee: Societe de Prospection et dInventions Techniques SPIT SAS
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Filing: 1977-05-02
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Granted: 1979-01-16
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Expires: 1997-05-02
Abstract
Abstract A fastener driving gun with a driving piston actuated by a cartridge to drive a fastener. The piston has an elongated shank with a tapered surface which engages a cooperating surface of the barrel, in the forward position of the piston, to prevent ejection of any substantial portion of the piston in the event of piston breakage. The taper of the piston can be 3% or less.
Inventors
- 👤 Pierre Termet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 14:05
CPC Classifications
B; B25; B25C; B25C1/00; B25C1/08; B25C1/10; B25C1/14; B25C1/143
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
176 words
A cartridge-actuated fastener driving tool including: a slidable assembly comprising a barrel, a muzzle at one end of said barrel, a cartridge chamber at the other end of said barrel, and a breech-block and percussion means for exploding a cartridge located at the end of said chamber remote from said barrel, a driving piston slidably mounted in said slidable assembly for actuation by the gases produced by an explosion in said cartridge chamber to eject a fastener from said muzzle, and a tubular casing, within which said slidable assembly is mounted for axial sliding movement, and having a handle with a trigger mounted on the casing near one end thereof, said driving piston comprising a head portion and a shank portion, said shank portion having at least at its forward end a frusto-conical abutting surface formed thereon for engaging a corresponding frusto-conical abutting surface formed on said slidable assembly for retaining a substantial part of said driving piston therein in case of breakage of said piston, said frusto-conical surfaces having a conicity of less than 3%.
Claim 2
Dependent Claim
176 words
A cartridge-actuated fastener driving tool including: a slidable assembly comprising a barrel, a muzzle at one end of said barrel, a cartridge chamber at the other end of said barrel, and a breech-block and percussion means for exploding a cartridge located at the end of said chamber remote from said barrel, a driving piston slidably mounted in said slidable assembly for actuation by the gases produced by an explosion in said cartridge chamber to eject a fastener from said muzzle, and a tubular casing, within which said slidable assembly is mounted for axial sliding movement, and having a handle with a trigger mounted on the casing near one end thereof, said driving piston comprising a head portion and a shank portion, said shank portion having at least at its forward end a frusto-conical abutting surface formed thereon for engaging a corresponding frusto-conical abutting surface formed on said slidable assembly for retaining a substantial part of said driving piston therein in case of breakage of said piston, said frusto-conical surfaces having a conicity of less than 3%.
Claim 3
Dependent Claim
26 words
A cartridge-actuated fastener driving tool according to claim 1, wherein said frusto-conical abutting surface of said shank portion extends over a substantial part of its length.
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) | 1982-01-15 | 1982-07-17 | 1983-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-01-15 | 1986-07-17 | 1987-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-01-15 | 1990-07-17 | 1991-01-16 | $7700.00 | Window Closed / Lapsed |