Method of, and apparatus for, controlling the advance of a tunnel drive shield
US4095436A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 21, 1977 |
| Grant date | Jun 20, 1978 |
| Priority date | — |
| Expiry date | Mar 21, 1997 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21D9/0692
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Apparatus is provided for controlling the advance of a tunnel drive shield. The drive shield is of the type having a plurality of elongate implements (or planks) which are supported and guided on a frame. Hydraulic rams are provided for moving the planks relative to the frame. The control apparatus comprises hydraulic ram means, which act between the frame and the permanent tunnel lining, and means for varying the pressure of hydraulic fluid applied to said hydraulic ram means. The frame can be advanced by applying hydraulic fluid to said hydraulic ram means and by simultaneously applying hydraulic fluid to at least one of said hydraulic rams. The direction of frame advance is controlled by varying the ratio of the pressures of the hydraulic fluid applied to said hydraulic ram means and to said at least one hydraulic ram.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.