Frostproof hydrant

Claim 1

A frostproof hydrant which comprises a riser, a chamber adjacent a lower end of the riser, a flexible diaphragm dividing the chamber into a pair of sections and having an area adjacent its margin rollable to lie in supported relation against the wall of the chamber, means connecting the lower end of the riser to the chamber on one side of the diaphragm, a diaphragm actuator having attached thereto a semi-floating diaphragm piston pivotable about axes transversely of actuator movement and which piston at a radial distance from said axes is attached to the diaphragm centrally thereof and said diaphragm having a cup shape portion lying in supported relation against the actuator piston, valve means for controlling flow of water from a main to the riser including spring means urging the valve to closed position and closing the valve except when the valve is engaged by the diaphragm actuator, piston and said valve means being provided with a valve actuator engageable by the diaphragm actuator piston when the diaphragm is adjacent the riser connection means for opening the valve to permit flow of water from the main to the riser, and means including said diaphragm actuator for moving the diaphragm actuator piston through the chamber in spaced relation to the walls thereof and in a direction away from the riser connection means when the valve is closed to increase the area of diaphragm supported by the chamber wall while decreasing the area of diaphragm supported by the actuator piston and drawing water from the riser into the chamber to be stored in the chamber below frost level and for advancing the diaphragm actuator piston through the chamber in an opposite direction to return the riser water to the riser with accompanying decrease in the area of diaphragm supported by the chamber wall and increase in the area of diaphragm supported by the actuator piston, said diaphragm moving means including a rod having a portion telescopically related to a portion of the diaphragm actuator piston and resilient means between the rod and the diaphragm actuator, piston portion the resilient means being loaded when the rod is moved in valve opening direction when the valve actuator is engaged by the diaphragm actuator, piston the resilient means causing rapid opening of the valve when valve closing force applied to The valve by the valve closing spring means and by pressure in the main is overcome by the loading of the resilient means.