Abstract: An apparatus for maintaining a tillage implement such as a plow at a consistent working depth utilizes a spring biased quadrilateral linkage to maintain the tillage implement in a position having to float forwardly and upwardly from the working depth thereby preventing unwanted flotation of the tillage implement from the working depth until the tillage implement encounters a substantially vertical load.

Abstract: A kit for modifying a digging bucket for controlling the depth cut, including an elongated member operationally connectable to a hoe bucket defining a cutting edge, an actuator operationally connectable to the elongated member, an electronic controller operationally connectable to the actuator, and a position sensor operationally connectable to the cutting edge and operationally connectable to the electronic controller. The actuator may be energized to pivot the elongated member to a position adjacent the cutting edge for engaging ground. Positioning of the elongated member adjacent the cutting edge prevents the cutting edge from digging ground.

Abstract: A kit for modifying a digging bucket for controlling the depth cut, including an elongated member operationally connectable to a hoe bucket defining a cutting edge, an actuator operationally connectable to the elongated member, an electronic controller operationally connectable to the actuator, and a position sensor operationally connectable to the cutting edge and operationally connectable to the electronic controller. The actuator may be energized to pivot the elongated member to a position adjacent the cutting edge for engaging ground. Positioning of the elongated member adjacent the cutting edge prevents the cutting edge from digging ground.

Abstract: A control-mode switching device includes: a plurality of actuators (2, 6, 7) that conduct different movement; driving means (10, 11, 12, 13, 14, 15) that drive the actuators; a plurality of control levers (22a-22c) that command operation of the driving means; a plurality of limit switches (72a-72e) that detect arrival of the control levers to the proximity of an end of a control range; a mode judging means (controller 23) that judges whether a priority operation mode is taken or not in accordance with a combination of on/off conditions of the limit switches; and a drive controlling means (controller 23) that, when it is judged by the mode judging means that the priority operation mode is taken, controls the driving means so that an output of selected one or more of the driving means becomes larger than that in a normal mode or the power ratio as compared with the other driving means becomes larger.