Patents Assigned to Geotechnical Instruments (UK) Limited
  • Gas analyzer
    Patent number: 5488227
    Abstract: A gas analyser and detector has an infra red source, a gas chamber and a detector cell; the detector cell has a gas sample inlet, inlet and exit paths for an infra red beam and reflector means in the chamber comprising a convex surface and a concave surface. The reflector means ensures a long path length for the beam whilst reducing beam divergence and signal loss.
    Type: Grant
    Filed: October 11, 1994
    Date of Patent: January 30, 1996
    Assignee: Geotechnical Instruments (UK) Limited
    Inventor: Christopher R. Sweet
  • Method and apparatus for measuring liquid level in the ground
    Patent number: 5027655
    Abstract: A method of detecting water level in an elongate cavity comprises emitting an alternating signal into the cavity, varying the frequency of said signal to provide a specific response from the cavity, detecting said response, and comparing said outgoing signal and response. In a preferred embodiment the response is a returning signal reflected from the surface of the water. The frequency of the outgoing signal may be varied continuously to establish a substantially steady state difference frequency between the outgoing and returning signal.
    Type: Grant
    Filed: October 3, 1989
    Date of Patent: July 2, 1991
    Assignee: Geotechnical Instruments (UK) Limited
    Inventor: Christopher R. Sweet