Hydraulic air injector

Claim 1

A HYDRAULIC AIR INJECTOR FOR THE PRESSURE TANK OF A WATER SYSTEM OR THE LIKE COMPRISING A WATER TANK, A WATER LINE LEADING INTO SAID TANK, A PIPE TO SERVICE MOUNTED IN SAID LINE, AN INJECTION APPARATUS INTERPOSED IN SAID LINE, BETWEEN SAID PIPE AND SAID TANK, SAID APPARATUS COMPRISING A PAIR OF VERTICALLY SPACED CYLINDERS, CONNECTED PISTONS MOUNTED IN SAID CYLINDERS, A VALVED PASSAGEWAY FROM THE LOWER CYLINDER TO THE WATER LINE FOR ADMITTING WATER TO SAID TANK WHEN THE PISTON IN SAID CYLINDER IS IN ITS FULLY RAISED POSITION AND A RETURN VALVED PASSAGEWAY FROM SAID CYLINDER TO SAID WATER LINE FOR ADMITTING WATER TO SAID LINE AND TO THE SERVICE PIPE WHEN THE PISTON IS IN ITS FULLY LOWERED POSITION, SAID UPPER CYLINDER HAVING A VALVED PASSAGEWAY EXTENDING INTO THE UPPER PORTION OF THE TANK FOR ADMITTING AIR AND WATER INTO THE TOP OF THE TANK, A SECOND-VALVED PASSAGEWAY AT THE UPPER END OF THE UPPER CYLINDER FOR ADMITTING AIR TO THE UPPER END OF THE UPPER CYLINDER, AND A BYPASS FORMED AT THE LOWER END OF THE UPPER CYLINDER.