Shear clamping mechanism

Claim 1

A SHEARING AND CLAMPING MECHANISM FOR TREE HARVESTING APPARATUS COMPRISING A SUPPORT FRAME, A PAIR OF SHEAR BLADES PIVOTALLY MOUNTED ON SAID SUPPORT FRAME FOR MOVEMENT TOWARD AND AWAY FROM EACH OTHER, HYDRAULIC MOTOR MEANS CONNECTED BETWEEN SAID SUPPORT FRAME AND EACH OF SAID SHEAR BLADES RESPECTIVELY FOR ACTUATING SAID BLADES IN A SHEARING OPERATION, A PAIR OF RIGID CLAMPING JAWS PIVOTALLY MOUNTED ON A FIXED PIVOT ON SAID SUPPORT FRAME FOR MOVEMENT TOWARD AND AWAY FROM EACH OTHER TO CLAMP THE TREE THEREBETWEEN, SEPARATE SPRING MEANS CONNECTED BETWEEN SAID SUPPORT FRAME AND EACH OF SAID CLAMPING JAWS FOR URGING THEM INTO CLAMPING ENGAGEMENT WITH THE TREE, A PAIR OF DETECT PINS ONE FIXEDLY SECURED WITH RESPECT TO EACH OF SAID SHEAR BLADES FOR MOVEMENT THEREWITH, SAID PINS BEING LOCATED BETWEEN INWARDLY FACING PORTIONS OF SAID CLAMPING JAWS TO ABUT SAID PORTIONS AND THEREBY CONSTRAIN SAID CLAMPING JAWS TO FOLLOW THE SHEARING MOVEMENT OF SAID SHEAR BLADES UNTIL THE SURFACE OF THE TREE IS ENGAGED AND THEN BECOME DISENGAGED FROM SAID PORTIONS, AND TO RE-ABUT SAID PORTIONS TO SEPARATE SAID JAWS AGAINST THE ACTION OF SAID SPRING MEANS UPON RETRACTION OF SAID SHEAR BLADES.