Apparatus for marking and for recovering oriented drill cores

Claim 1

IN CORE-DRILLING APPARATUS FOR MARKING OF ORIENTED DRILLING CORES FUNCTIONING SIMULTANEOUSLY AS CORE RECOVERING MEANS, A CORE DRILLING TUBE, A CORE BIT, MEANS CONNECTING SAID CORE BIT WITH SAID CORE DRILLING TUBE FOR JOINT ROTATION, A NON-ROTATING PROTECTING TUBE DISPOSED IN SAID CORE DRILL TUBE, AN ORIENTING DEVICE CONNECTED WITH AND DISPOSED ABOVE SAID PROTECTING TUBE, A BEARING MOUNTED IN SAID CORE DRILLING TUBE, SAID PROTECTING TUBE BEING SUSPENDED ON SAID BEARING, A MARKING KNIFE HOLDER CONNECTED WITH AND EXTENDING DOWNWARDLY FROM SAID NON-ROTATING PROTECTING TUBE, SAID MARKING KNIFE HOLDER HAVING A PLURALITY OF AXIALLY DISPOSED SLOTS PERIPHERYALL SPACED APART FROM EACH OTHER AND OPENING INTO THE INSIDE OF SAID MARKING KNIFE HOLDER, A MARKING KNIFE RECEIVED IN EACH OF SAID SLOTS AND HAVING AN UPPER END, SPRING MEANS URGING THE UPPER ENDS OF SAID MARKING KNIVES RADIALLY INWARD, A GUIDE PLUG HAVING AXIALLY DISPOSED GROVES AT ITS OUTER SURFACE AND RECEIVING SAID MARKING KNIVES IN SAID GROOVES, SAID GUIDE PLUG BEING NON-ROTATABLY MOUNTED IN SAID MARKING KNIFE HOLDER, A RADIALLY DISPOSED SHEARING PIN CONNECTING SAID GUIDE PLUG WITH PLUG CARRYING AT IS LOWER END VERTICALLY SAID GUIDE PLUG CARRYING AT IS LOWER END VERTICALLY DOWNWARDLY DIRECTED, RADIALLY DISPOSED VERTICAL CUTTING EDGES, THE LATTER PRESSING AT FIRST INTO THE BOTTOM OF THE DRILLING HOLE AND LATER INTO THE TOP OF SAID DRILLING CORE, IN ORDER TO PREVENT ROTATION OF SAID CONROTATING PROTECTING TUBE, THE NON-ROTATION OF THE LATTER BEING MAINTAINED AFTER SHEARING-OFF SAID SHEARING PIN BY SAID CORE DURING ITS PENETRATION INTO SAID MARKING KNIFE HOLDER, SAID MARKING KNIVES FORMING CUTS IN SAID CORE AS THE LATTER PENETRATES INTO SAID MARKING KNIFE HOLDER, SAID UPPER ENDS OF SAID MARKING KNIFE HOLDER, TO PENETRATE AND BE FORCED INTO SAID CUTS IN SAID CORE TO RETAIN THE SAID CORE IN THE SAID CORE DRILLING APPARATUS DURING THE RAISING OF THE LATTER AT THE COMPLETION OF THE CORE DRILLING OPERATION AND, SAID RADIALLY INWARD SPRING-BIASED MARKING KNIVES PREVENTING AN EASY RISING OF SAID GUIDE PLUG IN SAID MARKING KNIFE HOLDER DUE TO FRICTION BETWEEN SAID MARKING KNIVES AND SAID GUIDE PLUG, SO THAT A RIGID ENGAGEMENT IS RETAINED BETWEEN SAID RADIAL CUTTING BLADES OF SAID GUIDE PLUG AND SAID CORE, AS LONG AS SAID GUIDE PLUG MOVES AXIALLY STILL WITHIN THE RANGE OF SAID MARKING KNIVES.