US3850000A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tunnelling shields
Assignee: Kinnear Moddie Ltd
•
Filing: 1973-02-27
•
Granted: 1974-11-26
•
Expires: 1993-02-27
Abstract
Abstract A tunnelling shield has a rearward rotatable part having a spiral rearward end to engage a forward end of a spiral tunnel lining. A drive mechanism rotates the rearward shield part as further tunnel segments are laid one by one in the shield end against the previous segment to be erected. Rams advance the shield as the rearward end rotates to allow a newly erected segment to engage the tunnel wall.
Inventors
- 👤 R Mcbean
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:16
CPC Classifications
E; E21; E21D; E21D9/00; E21D9/06; E21D9/0607; E21D11/00; E21D11/04; E21D11/08; E21D19/00; E21D19/04
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
159 words
A tunnelling shield for use in erecting a spiral tunnel lining, the shield being of cylindrical form and having forward and rearward parts which are rotatable relatively to one another about the shield axis, the rearward part of the shield having a trailing end which has a spiral form extending between a step facing generally around the shield, so that in use the end of the shield can engage a partially erected spiral lining to support the ground adjacent the lining and each additional segment can be located in the shield adjacent said step and attached to the previously erected segment, the shield having means for rotating said rearward part of the shield with respect to the forward part of the shield in the opposite direction to which the step faces to withdraw the shield from the newly erected segment means to advance the shield along the tunnel simultaneously with said rotation of the rearward part of the shield.
Claim 2
Dependent Claim
159 words
A tunnelling shield for use in erecting a spiral tunnel lining, the shield being of cylindrical form and having forward and rearward parts which are rotatable relatively to one another about the shield axis, the rearward part of the shield having a trailing end which has a spiral form extending between a step facing generally around the shield, so that in use the end of the shield can engage a partially erected spiral lining to support the ground adjacent the lining and each additional segment can be located in the shield adjacent said step and attached to the previously erected segment, the shield having means for rotating said rearward part of the shield with respect to the forward part of the shield in the opposite direction to which the step faces to withdraw the shield from the newly erected segment means to advance the shield along the tunnel simultaneously with said rotation of the rearward part of the shield.
Claim 3
Dependent Claim
25 words
A tunnelling shield as claimed in claim 1 wherein said rearward part of the shield tapers around the shield to an edge at said step.
Claim 4
Dependent Claim
45 words
A tunnelling shield as claimed in claim 1 wherein the means to rotate the rearward part of the shield with respect to the forward part comprise a drive mechanism mounted on the forward part of the shield drivably engaging the rearward part of the shield.
Claim 5
Dependent Claim
55 words
A tunnelling shield as claimed in claim 3 wherein the drive mechanism comprises one or more drive motor spaced around the inner surface of the forward part of the shield, the or each motor having a drive pinion which meshes with a rack extending around the inner surface of the rearward part of the shield.
Claim 6
Dependent Claim
45 words
A tunnelling shield as claimed in claim 4 wherein the rack is formed by a plurality of rigidly mounted pins spaced around the inner surface of the rearward part of the shield with which the pinion or pinions of the or each drive motor mesh.
Claim 7
Dependent Claim
60 words
An apparatus as claimed in claim 3 wherein the means to rotate the rearward part of the shield with respect to the forward part of the shield comprise a ram mounted in the rearward part of the shield to act generally tangentially to the shield for pressing against a previously erected segment of the lining and thereby rotate the shield.
Claim 8
Dependent Claim
61 words
A tunnelling shield as claimed in claim 1 wherein the means for advancing the shield along the excavated tunnel comprise a plurality of hydraulic rams mounted around the inner surface of the forward part of the shield for extending through the rearward part of the shield to act on the end of the partially erected lining to drive the shield forward.
Claim 9
Dependent Claim
64 words
A tunnelling shield as claimed in claim 1 wherein the rearward part of the shield is supported on the forward part of the shield by a plurality of rollers mounted on the forward part of the shield for rotation about axes parallel to the shield axis and which rollers engage a track formed around the inner surface of the rearward part of the shield.
Claim 10
Dependent Claim
73 words
A tunnelling shield as claimed in claim 8 wherein the track comprises two elements spaced axially along the shields and each roller has two axially spaced surfaces for engaging the two elements respectively and an enlargement encircles the roller between said surfaces which enlargement engages between the elements so that the rearward part of the shield is supported for rotation and is axially located with respect to the forward part of the shield.
Claim 11
Dependent Claim
59 words
A tunnelling shield as claimed in claim 9 and in the case where the rearward part of the shield has a rack extending around the inner surface of the shield for engagement by motor driven pinions to rotate the rearward part of the shield wherein the rack for engagement by said drive pinions is mounted between said spaced elements.
Claim 12
Dependent Claim
69 words
A tunnelling shield as claimed in claim 1 wherein an annular seal is provided between the forward and rearward parts of said shield adjacent the outer surfaces thereof and means are provided for injecting a liquid lubricant between the adjacent parts of said shield outside the seal to flush spoil from between the parts of the shield and to provide a lubricant for the outer surface of the shield.
Claim 13
Dependent Claim
69 words
A tunnelling shield as claimed in claim 11 wherein a second annular seal is provided between the first seal and the outer surface of the shield and is arranged to prevent spoil passing towards the first seal from outside the shield whilst permitting said lubricant to flow outwardly to the shield surface and said injection means are arranged to deliver the lubricant liquid to the space between said seals.
Claim 14
Dependent Claim
25 words
A tunnelling shield as claimed in claim 12 wherein said means deliver bentonite into the space between the forward and rearward parts of the shield.
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) | 1977-11-25 | 1978-05-27 | 1978-11-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-25 | 1982-05-27 | 1982-11-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-25 | 1986-05-27 | 1986-11-26 | $7700.00 | Window Closed / Lapsed |