Patent ID: 6658768
Filing Date: 2003-12-09
Classification: E02F

Abstract:
A trencher comprising:(a) a carriage for movement over a working surface, the carriage having a steering mechanism for turning the carriage to follow a curved path, (b) an upright boom structure mounted to the carriage, (c) a digging chain support frame mounted to the boom structure for upward and downward translation relative to the boom structure along a substantially upright path, (d) an endless digging chain engageable with wheels rotatably mounted to the digging chain support frame and disposed so that the digging chain describes an upright path, (e) a chain drive motor for causing movement of the wheels and the digging chain, (f) a digging chain support frame actuator operatively coupled to the digging chain support frame for raising and lowering the digging chain support frame relative to the upright boom structure along a substantially upright path, and (g) an auger assembly adjustably mounted to the digging chain support frame for placement in a position corresponding to a desired trench depth, the auger assembly including an auger drive sprocket wheel for engaging the digging chain and at least two augers each mounted to the auger drive sprocket wheel on opposite sides thereof, the augers for transferring material away from the digging chain as the digging chain excavates material from a trench, whereby the upright digging chain may be lowered into the working surface by activation of the digging chain support frame actuator to excavate a trench as the augers of the auger assembly push excavated soil away from the trench and whereby the upright digging chain may also dig a curved trench as the trencher follows a curved path while the digging chain does not sufficiently interfere with the walls of the trench to impede the operation of the trencher.