Armature test apparatus including a pair of transformers and means for combining the secondary voltages thereof

Claim 1

IN ARMATURE TEST APPARATUS FOR AN ARMATURE HAVING A NUMBER OF COILS CONNECTED AT EACH END TO COMMUTATOR MEANS TO DEFINE AN ARMATURE WINDING, THE COMBINATION COMPRISING A FIXTURE FOR ROTATABLY SUPPORTING SAID ARMATURE, A PAIR OF CURRENT CARRYING MEMBERS FOR CONTACTING SAID COMMUTATOR MEANS, MEANS FOR SUPPORTING SAID CURRENT CARRYING MEMBERS, SAID ARMATURE BEING ADAPTED TO BE ROTATED DURING THE TESTING THEREOF WHILE SUPPORTED ON SAID FIXTURE RELATIVELY WITH RESPECT TO SAID CURRENT CARRYING MEMBERS, MEANS FOR IMPRESSING AN ALTERNATING VOLTAGE ACROSS THE COILS OF SAID ARMATURE AT A POWER LEVEL CORRESPONDING TO ACTUAL OPERATING CONDITIONS OF SAID ARMATURE, SAID LAST NAMED MEANS INCLUDING SAID CURRENT CARRYING MEMBERS AND BEING CONNECTED WITH THE COILS OF SAID ARMATURE DURING THE TESTING THEREOF TO PROVIDE TWO IDENTICAL CURRENT PATHS BETWEEN SAID CURRENT CARRYING MEMBERS THROUGH THE COILS OF SAID ARMATURE, FURTHER CONTACT MEMBERS CONNECTED WITH THE COILS OF SAID ARMATURE DURING TESTING THEREOF, SAID FURTHER CONTACT MEMBERS CONNECTING IDENTICAL CURRENT PATH PORTIONS OF SAID COIL CURRENT PATHS IN PARALLEL WITH CIRCUITS INCLUDING A TRANSFORMER HAVING PRIMARY AND SECONDARY WINDINGS, THE TURNS RATIO OF ONE OF SAID TRANSFORMERS BEING DIFFERENT FROM THE TURNS RATIO OF THE OTHER, MEANS FOR COMBINING THE VOLTAGES IMPRESSED ACROSS THE SECONARY WINDINGS OF SAID TRANSFORMERS, AND METER MEANS ADAPTED TO HAVE THE COMBINED VOLTAGES IMPRESSED THEREACROSS AS A MEASURE OF THE CONDITION OF THE WINDINGS IN ONE OF THE SAID CURRENT PATHS.