Hydraulic circuit tester

Claim 1

A PORTABLE HYDRAULIC CIRCUIT TESTER COMPRISING, A CASING HAVING A CONTINUOUS PASSAGEWAY THERETHROUGH, A MANIFOLD MOUNTED ON SAID CASING AND HAVING INLET AND OUTLET PORTS THEREIN CONNECTED TO THE ENDS OF SAID CONTINUOUS PASSAGEWAY IN SAID CASING, SAID PORTS BEING ADAPTED TO BE CONNECTED TO A HYDRAULIC CIRCUIT TO BE TESTED WHEREBY FLUID UNDER PRESSURE DEVELOPED IN THE CIRCUIT FLOWS THROUGH THE TESTER AND BACK TO THE CIRCUIT, A CHAMBER INCLUDED WITHIN SAID CASING AS A PART OF SAID CONTINUOUS PASSAGEWAY, A POSITIVE DISPLACEMENT METER POSITIONED IN SAID CHAMBER INCLUDING SHAFT MEANS EXTENDING THROUGH SAID CASING FROM SAID CHAMBER AND BEING CAUSED TO ROTATE WITH FLOW OF A FLUID THROUGH SAID CHAMBER, AN INDICATOR MOUNTED ON SAID CASING AND CONNECTED TO SAID SHAFT MEANS TO OPERATE IN ACCORDANCE WITH THE ROTATION OF SAID SHAFT MEANS AND FLOW OF THE FLUID THROUGH SAID CHAMBER, LOAD VARYING MEANS POSITIONED IN SAID PASSAGEWAY UPSTREAM OF SAID CHAMBER, A SECOND PASSAGEWAY INCLUDED IN SAID CASING AND CONNECTED TO SAID INLET PORT, SAID CAOND PASSAGEWAY HAVING A SUBSTANTIALLY SMALLER FLUID CAPACITY RELATIVE TO THE CAPACITY OF SAID PASSAGEWAY OF SAID CONTINUOUS PASSAGEWAY, A HIGH PRESSURE GAUGE CONNECTED IN SAID SECOND PASSAGEWAY, AN ADDITIONAL SMALL CAPACITY PASSAGEWAY CONNECTED TO SAID HIGH PRESSURE GAUGE, A LOW PRESSURE GAUGE CONNECTED TO SAID ADDITIONAL LOW CAPACITY PASSAGEWAY, PRESSURE RESPONSIVE VALVE MEANS INCLUDED IN SAID ADDITIONAL PASSAGEWAY AND ADAPTED UPON THE PRESENCE OF A HIGH PRESSURE IN SAID SECOND PASSAGEWAY TO ISOLATE THE LOW PRESSURE GAUGE FROM SAID SECOND PASSAGEWAY, AND A RELIEF PASSAGE INCLUDED IN PART IN SAID PRESSURE RESPONSIVE VALVE AND IN PART IN SAID CASING AND ADAPTED TO CONNECT THE LOW PRESSURE GAUGE TO SAID CHAMBER WHENEVER A LOW PRESSURE GAUGE IS ISOLATED FROM SAID SECOND PASSAGEWAY.