Lash adjusting device

Claim 1

A LASH ADJUSTING SYSTEM OF THE MECHANICAL TYPE FOR A VALVE OPERATING TRAIN OF AN ENGINE COMPRISING IN COMBINATION THEREWITH AN ADJUSTABLE PUSH ROD INCLUDING A SCREW MEMBER AND A NUT MEMBER THREADED TOGETHER TO FORM A PAIR OF ADJUSTING MEMBERS, ONE OF THE ADJUSTING MEMBERS BEING SECURED AGAINST ROTATION RELATIVE TO THE OTHER IN A DIRECTION WHICH WOULD VARY THE EFFECTIVE LENGTH OF THE TRAIN AND THE OTHER ADJUSTING MEMBER BEING ROTATABLE IN ONE DIRECTION AND RETURN THROUGH A LIMITED STROKE TO DECREASE AND INCREASE, RESPECTIVELY, THE EFFECTIVE LENGTH OF THE TRAIN BY A PREDETERMINED AMOUNT, A SINGLE PAIR OF ONE-WAY DRIVE ABUTMENTS MOVABLE TOWARD AND AWAY FROM ONE ANOTHER BETWEEN SPACED AND ENGAGED RELATIONSHIPS IN RESPONSE TO VALVE OPENING AND VALVE CLOSING MOTION OF THE TRAIN, RESPECTIVELY, ONE OF THE ABUTMENTS BEING ASSOCIATED WITH THE OTHER ADJUSTING MEMBER AND THE OTHER ABUTMENT BEING LOCATED ON THE ENGINE TO ENGAGE THE ONE ABUTMENT PART WAY THROUGH THE VALVE OPENING MOTION OF THE TRAIN AND THEREAFTER COMPULSIVELY ROTATE THE OTHER ADJUSTING MEMBER IN THE ONE DIRECTION FROM A MID-STROKE POSITION THROUGH THE DISTANCE REQUIRED TO REACH THE LIMIT OF ITS STROKE TO CREATE A CORRESPONDING AMOUNT OF POTENTIAL LASH IN THE TRAIN, THE SCREW THREAD HELIX ANGLE BEING INHERENTLY SELFLOCKING AGAINST THE FORCE OF VALVE TRAIN LOAD TO RETAIN SUCH AMOUNT OF POTENTIAL LASH IN THE TRAIN DURING VALVE CLOSING MOTION OF THE TRAIN AS THE ABUTMENTS DISENGAGE AND MOVE AWAY FROM ONE ANOTHER, AND A LASH TAKE-UP SPRING HAVING INSUFFICIENT FORCE TO ROTATE THE OTHER ADJUSTING MEMBER WHILE THE TRAIN IS LOADED AND CONNECTED TO ROTATE THE OTHER ADJUSTING MEMBER IN THE RETURN DIRECTION AWAY FROM ITS STROKE LIMIT TO A MID-STROKE POSITION THROUGH THE DISTANCE REQUIRED TO REMOVE ACTUAL LASH FROM THE TRAIN AS THE LOAD ON THE TRAIN IS RELIEVED BY SEATING OF THE VALVE.