Alternative dosing device for injecting a dose of product in a main fluid annex.

摘要

The invention relates to a reciprocating metering device (1) for injecting a variable metered quantity of auxiliary product into a main fluid. It includes a piston (9) actuated by a movable element of a reciprocating pump through which the main fluid passes and which is mounted so as to slide in a cylinder body (4) comprising a stationary liner (11) and a metering body (15) mounted so that it slides in the liner (11). The metering body (15) is fixed to the liner (11) with the aid of a key (wedge) (28a, 28b) interacting with a housing formed by a notch (30) formed in the liner (11) and an external groove (31) of the metering body (15). The metering body (15) exhibits a plurality of grooves (31) spaced by a spacing (P), and the liner (11) includes a plurality of notches (30) spaced by a spacing (P') which is other than a multiple of (P). IMAGE