Abstract: A walk-behind trenching implement has a side mounted rotary trenching tool for creating a profiled trench into the surface of the earth, which can also be used as an implement to edge landscape beds. The trenching implement is powered by an engine that delivers rotational power in an unbalanced manner to the wheel adjacent to the rotatable trenching tool. The wheel opposite to the trenching tool is can be non-powered to freely rotate as the implement is moved across the surface of the ground, or braked to unbalance power delivery through a differential. This unbalanced propulsion drive induces a skewing action into the operation of the implement that counterbalances the opposite skewing action resulting from the operation of the trenching tool to provide a more smoothly operating implement. A trenching tool having a configuration conducive to profile modification allows flexibility in the desired shape of the trench being formed.

Abstract: A walk-behind power unit is configured to detachably mount a variety of work implements to perform a corresponding variety of operations from a single power unit. The power unit includes an implement mounting mechanism that is pivotable about a generally vertical pivot axis corresponding to the power output shaft of the engine on the power unit. An attached work implement can be moved laterally to change the operating characteristics through pivoting the implement to either side of a normal direction of travel. An landscape edger implement can be mounted so that the width of cut of the cutting disk is varied as the edger implement is pivoted. A mower implement can be attached so that the cutting path of the mower blade is offset laterally as the implement is pivoted, thus permitting the mower to mow around obstacles offset to the side of the direction of travel.