Hard rock trench cutting machine having anchoring and steering structure

Claim 1

A hard rock trench cutting machine for cutting a trench having an end face, two opposed sidewalls, a bottom wall, an open top, a longitudinal axis extending parallel to said sidewalls and to said bottom wall, and a lateral axis extending between said sidewalls perpendicular to said longitudinal axis and parallel to said bottom wall, said machine comprising a main body assembly and a cutter wheel and a longitudinal thrust assembly movable along said longitudinal axis with respect to said main body assembly and said cutter wheel, cylinder means on said longitudinal thrust assembly transversely mounted with respect to the longitudinal axis of said main body assembly, piston means extending axially from each end of said cylinder means and carrying means adapted to bear against opposed walls of the trench, each of said piston means having an end face within said cylinder means which, together with an inner sidewall of said cylinder, comprise a pressure chamber adapted to force said piston means against said opposed sidewalls, said main body assembly and said cylinder means being adapted to move laterally relative to said piston means with said pressure chamber pressurized, said cutter wheel being rotatably carried by said main body assembly for rotation about a rotational axis relative to said main body assembly, said rotational axis being substantially perpendicular to said lateral axis, a plurality of individual cutters mounted on said cutter wheel for engaging said trench end face, said individual cutters extending along said trench end face continuously from said bottom wall to said open top, rotational drive means rotating said cutter wheel about said rotational axis relative to said main body assembly, extensible means between said piston means and said main body assembly for forcing the main body assembly and said cutter wheel forwardly with respect to said longitudinal thrust assembly to progressively cut a trench, and steering means to shift said main body assembly laterally relative to said piston means and about said central axis.