Resources Contact Us Home
Tunnelling shields and like moveable apparatus

Image Number 2 for United States Patent #4273468.

Corrections to be applied to the motion of a tunnelling shield to maintain or restore motion of the shield along a predetermined path are determined by directing a beam of collimated light in a direction parallel to or at a fixed angle with the axis of said predetermined path; focussing the beam on to the input end of an optical cable carried by the shield and comprising a plurality of optical fibres, the input ends of the fibres being arranged in an array in which the position of the input end of each guide relative to that of another is fixed; and displaying light transmitted through the optical cable or guides on to a screen at which the output ends of the guides are so arranged as to facilitate ready determination of any correction required to be applied to the motion of the shield. The method may be employed to indicate which propulsion rams of a tunnelling shield should be operated to apply the necessary correction to the motion of the shield.

  Recently Added Patents
Rain barrel
High electron mobility transistor and manufacturing method thereof
System and method for selecting a video encoding format based on feedback data
System and method for transferring data in storage controllers
FET device having ultra-low on-resistance and low gate charge
Method and apparatus for controlling a multi-node process
System and method for storing redundant information
  Randomly Featured Patents
Refresh cell for a random access memory
Fuel injection apparatus for internal combustion engine
Optical film and liquid crystal display using the same
Measuring method by spectrum analyzer
Closure devices, related delivery methods and tools, and related methods of use
Semiconductor device and method of manufacturing the same
Stepping motor drive controlling circuit
Generator for producing multiple signals which are synchronous with each other
Universal adjustable spacer assembly
Sample treating method and apparatus