Hydraulic pumping unit

Claim 1

A HYDRAULIC WELL PUMP COMPRISING A BASE, AN UPSTANDING SAMSON POST ON THE BASE, A GENERALLY HORIZONTAL WALKING BEAM PIVOTED INTERMEDIATE ITS ENDS ON THE POST, A WELL STRING SECURED TO ONE END OF THE WALKING BEAM, A COUNTERBALANCE WEIGHT SLIDABLY MOUNTED ON THE WALKING BEAM ADJACENT ITS OPPOSITE END, A HYDRAULIC CYLINDER MOUNTED ON THE WALKING BEAM IN PARALLEL RELATIONSHIP THERETO AND HAVING A PISTON PROVIDED WITH A PISTON ROD, MEANS CONNECTING SAID PISTON ROD TO SAID COUNTERBALANCE WEIGHT, A HYDRAULIC RAM PIVOTED TO THE WALKING BEAM OPPOSITE SAID COUNTERBALANCE WEIGHT AND PIVOTED ON THE BASE, DISTRIBUTING VALVE MEANS CONNECTED BETWEEN SAID HYDRAULIC CYLINDER AND SAID HYDRAULIC RAM, A HYDRAULIC VALVE OPERATOR, SAID VALVE OPERATOR COMPRISING A PILOT VALVE CYLINDER MEMBER CONTAINING A PLUNGER MEMBER, ONE OF SAID MEMBERS BEING PIVOTALLY CONNECTED TO THE WALKING BEAM AND THE OTHER MEMBER BEING PIVOTALLY CONNECTED TO THE POST, THE PLUNGER MEMBER BEING CONTINUOUSLY MOVED IN THE CYLINDER MEMBER AS THE WALKING BEAM OSCILLATES ON THE POST, A HYDRAULIC RETURN LINE CONNECTED TO THE DISTRIBUTING VALVE MEANS AND THE VALVE OPERATOR, AND A FLUID PRESSURE LINE CONNECTED TO THE DISTRIBUTING VALVE MEANS THROUGH THE VALVE OPERATOR, SAID VALVE OPERATOR BEING PROVIDED WITH MEANS TO OPERATE THE DISTRIBUTING VALVE MEANS RESPONSIVE TO THE MOVEMENT OF THE PLUNGER MEMBER IN THE CYLINDER MEMBER.