Injector device for an apparatus suitable for mixing chemically reactive components

Abstract

An injector device for supplying a chemically reactive component to a mixing head includes a modular structure defined by a hollow housing and guiding body extending around a longitudinal symmetry axis and having one or more supply openings for supplying the chemically reactive component; in the hollow body a nozzle orifice is obtained arranged to face and communicate with a mixing chamber obtained in the mixing head; a pin-shaped partialization and control element, which is housed and slidably movable—along the longitudinal symmetry axis—in the hollow body and configured to vary a narrowed active section of the nozzle orifice; on the partialization and control element a tip portion is obtained that is conformed to receive pressure from the respective polymer component delivered to said hollow body so as to move away said partialization and control element from said nozzle orifice to vary the area of said narrowed active section; a modular adjusting and contrasting unit, which is removably couplable with the hollow body and with the partialization and control element and configured to exert an axisymmetric thrust action on the partialization and control element to arrange the partialization and control element in an initial position and preload condition to adapt the narrowed active section to a reference flowrate and pressure of the polymer component and subsequently to vary the position of said partialization and control element to adjust the narrowed active section according to the flowrate variation, exerting the contrasting force that is suitable for balancing the pressure exerted by the polymer component; the modular adjusting and contrasting unit includes a series of interchangeable elastic elements of conical disc shape, configured to exert a non-linear elastic action that is such as to contain the retracting stroke of the partialization and control element, limiting as much as possible the pressure variation at the variation of the flowrate of the respective polymer component entering the hollow housing and guiding body; the modular adjusting and contrasting unit, the tip portion and the nozzle orifice cooperate mutually to confer to the injector device a geometric conformation with high section gain, corresponding to a high ratio between the variation of the area of narrowed active section and the longitudinal shift of the partialization and control element.