US3879771A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic ram
Assignee: ThreeBond Co Ltd
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Filing: 1973-10-15
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Granted: 1975-04-29
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Expires: 1993-10-15
Abstract
Abstract This invention relates to hydraulic rams for use in clearing blocked pipes, drains, and other conduits, and of the kind in which a sudden application of gas pressure is employed to impart a shock against the blockage.
Inventors
- 👤 Yasuji Nakane
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:13
CPC Classifications
E; E03; E03C; E03C1/00; E03C1/12; E03C1/30; E03C1/304; Y; Y10; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7837; Y10T137/7859; Y10T137/7861
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
212 words
A ram for releasing gas under pressure to clear a clogged conduit, comprising: an axially extending central shaft; a peripheral cylinder surrounding said shaft, said shaft projecting at both of its ends from said cylinder, said cylinder forming a cavity around said shaft for the reception of gas under pressure; means on a first end of said shaft to mount a gas bomb, including piercing means to pierce the gas bomb and release its contents, said shaft including a first conduit extending from said piercing means to said cavity and second conduit means extending from the other end of the shaft to a valving aperture on the peripheral wall thereof; a first seal making a fluid-tight sliding seal between the cylinder and the shaft, and located between the cavity and the said first end; a second seal making a fluid-tight sliding seal between the cylinder and the shaft and located between the cavity and the other end of the shaft and also between the valving aperture and the cavity when the shaft is in a first axial position whereby to isolate the second conduit from the cavity in that position, the shaft and the cylinder being relatively slidable so the valving aperture can communicate with the cavity in a second axial position.
Claim 2
Dependent Claim
212 words
A ram for releasing gas under pressure to clear a clogged conduit, comprising: an axially extending central shaft; a peripheral cylinder surrounding said shaft, said shaft projecting at both of its ends from said cylinder, said cylinder forming a cavity around said shaft for the reception of gas under pressure; means on a first end of said shaft to mount a gas bomb, including piercing means to pierce the gas bomb and release its contents, said shaft including a first conduit extending from said piercing means to said cavity and second conduit means extending from the other end of the shaft to a valving aperture on the peripheral wall thereof; a first seal making a fluid-tight sliding seal between the cylinder and the shaft, and located between the cavity and the said first end; a second seal making a fluid-tight sliding seal between the cylinder and the shaft and located between the cavity and the other end of the shaft and also between the valving aperture and the cavity when the shaft is in a first axial position whereby to isolate the second conduit from the cavity in that position, the shaft and the cylinder being relatively slidable so the valving aperture can communicate with the cavity in a second axial position.
Claim 3
Dependent Claim
24 words
A ram according to claim 1 in which spring means opposed between the shaft and the cylinder bias the shaft toward said first position.
Claim 4
Dependent Claim
23 words
A ram according to claim 1 in which the means to mount the gas bomb comprises a sleeve threadedly attachable to the shaft.
Claim 5
Dependent Claim
40 words
A ram according to claim 1 in which a joint member comprises a tube adapted to surround and project beyond the gas bomb and bear against the cylinder to provide handle means for shifting the cylinder relative to the shaft.
Claim 6
Dependent Claim
24 words
A ram according to claim 4 in which spring means opposed between the shaft and the cylinder bias the shaft toward said first position.
Claim 7
Dependent Claim
23 words
A ram according to claim 5 in which the means to mount the gas bomb comprises a sleeve threadedly attachable to the shaft.
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) | 1978-04-28 | 1978-10-28 | 1979-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-28 | 1982-10-28 | 1983-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-28 | 1986-10-28 | 1987-04-29 | $7700.00 | Window Closed / Lapsed |