Patent ID: 7644524

Claim:
A walk-behind steerable trencher, comprising: a frame; two independently powered and spaced-apart, ground-engaging drive members positioned on opposing sides of the frame; a trenching boom comprising: an elongate boom guide; an attachment arm defining a transverse pivot joint for pivotally attaching a proximal end of the boom guide to a forward portion of the frame, the transverse pivot joint defining a first transverse axis; an endless cutting element movable along a perimeter of the boom guide; and a drive unit attached to the attachment arm, the drive unit for moving the cutting element along the perimeter of the boom guide, wherein the drive unit comprises a driven axle defining a second transverse axis that is offset from the first transverse axis; and an actuator coupled between the frame and the trenching boom, the actuator operable to pivot the trenching boom, about the first transverse axis, from an operating position, wherein a distal end of the boom is below a ground surface, to a transport position, wherein a distal end of the boom is elevated forward of the forward portion of the frame such that a lowermost portion of the cutting element is positioned above an inclined plane that extends upwardly, forwardly, and tangentially from a forwardmost portion of one of the ground-engaging drive members at an angle of 25 degrees or more from horizontal.