Adjustable hydraulic trip release

Claim 1

IN A JAR MECHANISM: A MANDREL UNIT; A BARREL UNIT TELESCOPICALLY ARRANGED RELATIVE TO THE MANDREL UNIT; MECHANICAL TRIP RELEASE MEANS EMBODIED IN SAID MECHANISM AND RELEASABLY INTERCONNECTING THE UNITS TOGETHER, SAID UNITS BEING NORMALLY LOCKED BY SAID MECHANICAL TRIP RELEASE MEANS AGAINST RELATIVE MOVEMENT; A TRIP RING ON THE MANDREL UNIT HAVING ONE END ENGAGED BY SAID TRIP RELEASE MEANS; HYDRAULIC TRIP RELEASE CONTROL MEANS WITHIN SAID BARREL UNIT FOR EFFECTING RELEASE OF THE TRIP RELEASE MEANS IN ACCORDANCE WITH THE FORCE OF THE LONGITUDINAL PULL IN ONE DIRECTION ON THE BARREL UNIT, THE OTHER END OF SAID TRIP RING OPERABLY ENGAGING SAID HYDRAULIC TRIP RELEASE CONTROL MEANS; NORMALLY INOPERATIVE SPRING MEANS OPERABLY DISPOSED IN SAID BARREL UNIT BETWEEN SAID MECHANICAL TRIP RELEASE MEANS AND SAID HYDRAULIC TRIP RELEASE CONTROL MEANS; AND MEANS SECURING SAID HYDRAULIC TRIP RELEASE CONTROL MEANS IN A PREDETERMINED POSITION IN SAID BARREL AND RELEASABLE WHEN A FORCE IS APPLIED TO SAID BARREL UNIT IN EXCESS OF A PREDETERMINED VALUE.