Precision tillage unit

Claim 1

IN AN EARTH-WORKING IMPLEMENT FOR MOUNTING ON A TRACTOR HAVING VERTICALLY MOVABLE DRAFT SENSING HITCH MEANS THEREON, A FIRST RIGID TRANSVERSE TOOL CARRIER CONNECTED TO SAID HITCH MEANS TO BE RAISED AND LOWERED THEREWITH AND FOR AUTOMATIC VERTICAL ADJUSTMENT OF SAID TOOL CARRIER IN RESPONSE TO CHANGES IN DRAFT CONDITIONS, EARTH-WORKING TOOLS RIGIDLY MOUNTED ON SAID TOOL CARRIER AND EXTENDING DOWNWARDLY THEREFROM TO PENETRATE RELATIVELY DEEPLY INTO THE SOIL, A SECOND RIGID TRANSVERSE TOOL CARRIER DISPOSED REARWARDLY OF SAID FIRST TOOL CARRIER, EARTH-WORKING TOOLS RIGIDLY MOUNTED ON SAID SECOND CARRIER AT LOCATIONS LATERALLY REMOVED FROM THE TOOLS ON SAID FIRST TOOL CARRIER AND EXTENDING DOWNWARDLY THEREFROM TO PENETRATE THE SOIL AT A RELATIVELY SHALLOW DEPTH, LINKAGE EXTENDING BETWEEN AND PIVOTALLY CONNECTED AT ITS ENDS TO SAID FIRST AND SECOND TOOL CARRIERS TO ACCOMMODATE VERTIAL FLOATING MOVEMENT OF SAID SECOND CARRIER RELATIVE TO SAID FIRST CARRIER, AND A GUAGE WHEEL MOUNTED ON SAID SECOND CARRIER AND ENGAGEABLE WITH THE GROUND TO MAINTAIN A CONSTANT OPERATING DEPTH FOR THE TOOLS ON SAID SECOND CARRIER IRRESPECTIVE OF THE VERTICAL MOVEMENT OF SAID FIRST TOOL CARRIER.