Plow system with plurality of plow units and means for adjusting spacing between units in a continuous manner

Claim 1

In a semi-mounted plow system adapted to be pulled by a traction vehicle and including a main frame having a horizontal beam inclined relative to the direction of travel of said vehicle and semi-mounted to said vehicle for rotation about a vertical hitch axis, a plurality of plow units mounted at spaced locations along said horizontal beam for rotation about respective vertical axes, each unit provided with a ground-working implement, the improvement comprising: power-actuated means for rotating all of said plow units together to adjust the spacing between adjacent plow units to thereby adjust the width of a furrow cut by said units; tail section means including a rear steering wheel and connected to the rear end of said horizontal beam for supporting the distal end of said main frame on the ground; and steering means connected between said vehicle and said steering wheel for steering said tail section means as said vehicle moves; said improvement being characterized in that the spacing of said plow units relative to each other on said horizontal beam, the spacing of the axes of rotation of said plow units relative to said hitch axis, and the location of the foremost plow unit relative to the rear furrow wheel of said vehicle and said hitch axis are such that as said power-actuated means rotates said units to adjust the furrow width cut by adjacent units, said inclined horizontal beam is rotated about the hitch axis such that all of said units travel along predetermines arcs centered at said hitch axis, and the lateral spacing between said foremost unit and said furrow wheel is adjusted to be substantially the same as the adjusted furrow width cut by adjacent ones of the other plow units, said steering means being responsive to the adjustment of said plow units to rotate the rear end of said horizontal frame in the required direction about said hitch axis.