Liquid additive metering device.

摘要

The device comprises a major-diameter first piston one face of which is acted upon by the pulsed pressure of a line feeding an irrigation plant, in order to periodically displace the piston against the action of resilient means. The other face of the said piston carries an axial cylindrical appendix capable to close a through hole in the bottom of a cup-shaped minordiameter second piston slidable against the action of spring means, in a cavity connected with the said line through a non return valve. A reservoir containing a liquid additive is connected to the part of the cavity containing the cylindrical appendix of the first piston.