Patent ID: 6016616
Filing Date: 2000-01-25
Classification: E02F

Abstract:
Excavating apparatus comprising:a prime mover having excavating means for excavating a trench with a floor which is to be substantially parallel to a reference signal, said excavating means defining an end thereof remote from said prime mover, said excavating means having a rotatable member having an axis of rotation, and a plurality of cutting tools which travel around said rotatable member at said end of said excavating means remote from said prime mover, and said excavating means being pivotable relative to said prime mover to vary the depth of said trench, said cutting tools defining a lowest excavating surface of said excavating means;sensor means for detecting said reference signal;detector means for detecting if said sensor means moves out of a required angular position relative to the reference signal;means for moving said sensor means relative to said excavating means along a first path to return the sensor means to said required angular position; andguide means for defining said first path of movement of said sensor means relative to said excavating means to be an arcuate first path, said arcuate first path having a center of curvature generally at said axis of rotation of said rotatable member of said excavating means, said arcuate first path being such that, as said excavating means pivots, said sensor means moves relative to said prime mover along a second path, and said lowest excavating surface moves relative to said prime mover along a third path, said second path of movement of said sensor relative to said prime mover being substantially the same in direction and distance as said third path of movement relative to said prime mover of said lowest excavating surface of said excavating means.