Patent US3630574A successfully refreshed from Google Patents.
US3630574A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tunneling machine with steering shield
Assignee: Edmund Nuttall Sons and Co London Ltd
•
Filing: 1970-02-26
•
Granted: 1971-12-28
•
Expires: 1990-02-26
Abstract
Abstract A tunneling machine, primarily for use in tunneling through hard ground. A digging assembly of conventional nature is mounted on a shield, but contrary to normal practice, the shield is smaller in radius than the tunnel cut by the digging assembly. At the forward end of the underside the shield is provided with a rocking pad on which the whole shield and digging assembly is bodily rockable to steer the machine. The rocking is achieved by pressing members, e.g. in the form of jacks, mounted in the shield and adapted to press against the tunnel wall.
Inventors
- 👤 Alan James Cox
- 👤 Roy Patrick Burgess
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 06:08
CPC Classifications
E; E21; E21D; E21D9/00; E21D9/06; E21D9/08; E21D9/0875; E21D9/0879
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
115 words
In a tunneling machine comprising a shield and a digging assembly mounted on a forward end of the shield to cut a tunnel of a predetermined radius, the improvement that the shield is smaller in radius than the tunnel cut by the digging assembly and that the shield has a rocking pad mounted on a forward zone of its underside to contact the lower surface of the tunnel to provide at least limited rocking movement for the shield and digging assembly, the shield further comprises a plurality of pressing members mounted thereon for pressing against the tunnel wall to provide positive steering of the shield and digging assembly by rocking them about the rocking pad.
Claim 2
Dependent Claim
115 words
In a tunneling machine comprising a shield and a digging assembly mounted on a forward end of the shield to cut a tunnel of a predetermined radius, the improvement that the shield is smaller in radius than the tunnel cut by the digging assembly and that the shield has a rocking pad mounted on a forward zone of its underside to contact the lower surface of the tunnel to provide at least limited rocking movement for the shield and digging assembly, the shield further comprises a plurality of pressing members mounted thereon for pressing against the tunnel wall to provide positive steering of the shield and digging assembly by rocking them about the rocking pad.
Claim 3
Dependent Claim
37 words
A tunneling machine as claimed in claim 1, in which the shield comprises main thrust anchor pads, an upper central portion and a lower central portion, said central portions extending rearwardly between the main thrust anchor pads.
Claim 4
Dependent Claim
24 words
A tunneling machine as claimed in claim 1, wherein the pressing members comprising pressing pads and hydraulic jacks adapted to actuate the pressing pads.
Claim 5
Dependent Claim
43 words
A tunneling machine as claimed in claim 3, in which the pressing pads are four in number and are mounted on the shield such that one acts vertically upward, one acts vertically downward and the other two act one in each lateral direction.
Claim 6
Dependent Claim
52 words
A tunneling machine as claimed in claim 4, in which the shield comprises main thrust anchor pads, an upper central portion and a lower central portion, said central portions extending rearwardly between the main thrust anchor pads, the vertically acting pressing pads being mounted on the respective rearward extensions of the shield.
Claim 7
Dependent Claim
25 words
A tunneling machine as claimed in claim 4, in which the horizontally and laterally acting pressing pads are mounted slightly rearwardly of the rocking pad.
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) | 1974-12-27 | 1975-06-28 | 1975-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-27 | 1979-06-28 | 1979-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-27 | 1983-06-28 | 1983-12-28 | $7700.00 | Window Closed / Lapsed |