UNDERGROUND FIRE HYDRANT Russian patent published in 2001 - IPC

FIELD: water supply system. SUBSTANCE: fire hydrant has column with valve installed on fire stand in inspection pit. Lower part of fire stand is provided with cylindrical insert accommodating impeller which is free to rotate on shaft aligned with stand axis; magnetically permeable tips are installed on ends of impeller blades. Hole is made in cylindrical insert body to receive hollow plug; the latter accommodates parallel-connected coil-and-core assembly and diode; anode of mentioned diode is connected to starting lead of coil and to ground; finishing lead of coil is connected to corrector input by means of sealed cable passed inside shielding case and telescopic tube one of whose ends is hinged to shielding case; in addition, fire hydrant is provided with hermetically sealed shielded housing accommodating normalizer, electrical energy storage, electronic switch, and meter-annunciator connected in series by means of mentioned corrector. EFFECT: provision for measuring total water discharge (for certain period of time) with aid of fire hydrant and ensuring remote reading of discharge (outside inspection pit). 3 cl, 1 dwg