Safety control for hydraulic mold machine with low pressure closing

Claim 1

IN A MACHINE OF THE CLASS WHEREIN A MOVABLE DIE PART IS MOVED TOWARD AND FROM A RELATIVELY FIXED DIE PART TO CLOSE AND OPEN A DIE BY A MOTOR, AND WHEREIN THE FINAL MOVEMENT OF THE MOVABLE DIE PART IS CONTROLLED BY SAFETY CONTROL MEANS THAT ARE INDEPENDENT OF THE SPEED OF THE MOVABLE DIE PART TOWARD SUBSTANTIALLY CLOSED POSITION, THE COMBINATION WITH THE DIE PARTS OF (A) FIRST FLUID MEANS FOR SUPPLYING WORKING FLUID TO THE MOTOR AT LOW PRESSURE TO OPERATE THE MOVABLE DIE BETWEEN OPEN AND CLOSED POSITIONS, CYCLE CONTROL APPARTUS FOR CONTROLLING SAID FIRST FLUID SUPPLY MEANS, (B) SECOND FLUID SUPPLY MEANS FOR SUPPLYING WORKING FLUID TO THE MOTOR AT HIGH PRESSURE, (C) A FIRST ELECTRIC CIRCUIT HAVING CONTACTS OPERABLY CONNECTED WITH THE DIE PARTS AND ONE OF WHICH MOVES WITH A DIE PART TO BRING THE CONTACTS TOGETHER AND TO CLOSE THE FIRST CIRCUIT WHEN THE DIE PARTS MOVE INTO SUBSTANIALLY CLOSED POSITION, (D) A SECOND ELECTRIC CIRCUIT INCLUDING CONTACTS CONNECTED WITH THE DIE PARTS SIMILARLY TO THE CONTACTS OF THE FIST ELECTRIC CIRCUIT BUT IN POSITIONS TO TOUCH ONE ANOTHER INTIALLY AND TO CLOSE THE SECOND ELECTRIC CIRCUIT ONLY AFTER THE DIES ARE CLOSER TOGETHER THAN WHEN THE CONTACTS OF THE FIRST CIRCUIT TOUCHED ONE ANOTHER, (E) THE SAFETY CONTROL MEANS BEING OPERABLY CONNECTED WITH BOTH THE FIRST AND SECOND ELECTRIC CIRCUITS SO AS TO REQUIRE THAT BOTH CIRCUITS BE CLOSED AT THE SAME TIME AS A PREREQUISITE TO THE FINAL CLOSING OF THE DIES UNDER PRESSURE, (F) THE SAFETY CONTROL MEANS INCLUDING A TIMER MEANS FOR STARTING OPERATION OF THE TIMER WHEN THE MOVABLE DIE PART MOVES INTO SUBSTANTIALLY CLOSED POSITION WITH RESPECT TO THE RELATIVELY FIXED DIE PART, AND A CONTROL CIRCUIT RESPONSIVE TO THE OPERATION OF THE TIMER FOR PREVENTING THE APPLICATION OF FINAL CLOSING PRESSURE TO THE MOTOR WHEN THE TIME BETWEEN THE CLOSING OF THE FIRST AND SECOND ELECTRIC CIRCUITS EXCEEDS A PERIOD DETERMINED BY THE TIMER.