FLUSHMETER PISTON

Abstract

The advantages of our invention over the prior art are: 1) it reduces the drag forces exerted on the piston by water pressure, thus aiding and balancing its buoyancy; 2) it provides a homogeneous thrust and crushing force on the double-lip rubber, eliminating the uncertainty of a controlled tightening torque; 3) it results in controlled deformation of the rubber; and 4) it ensures balanced concentricity. Structurally, the piston of the present invention comprises, in its upper part, a bushing nut (1) that secures the double-lip rubber (2) to the piston body (3) by being threaded through the external thread of the bushing nut (1), which engages with the upper internal thread of the piston body (3). The bushing nut (1) has an upper flange that presses the double-lip rubber (2) against the upper part of the piston body.