公开(公告)号：US20200307025A1

公开(公告)日：2020-10-01

申请号：US16826631

申请日：2020-03-23

Applicant: AFROS S.p.A.

Inventor： Marco VOLPATO ,  Maurizio CORTI ,  Giorgio MOLTENI ,  Fabio FINI

IPC: B29B7/76 ,  B29B7/74

Abstract: A high-pressure mixing device adapted to form a polymeric mixture from the reaction of two or more reactive liquid components or resins, comprises a head-body provided with a mixing chamber having an inner cylindrical surface with inlet and outlet openings for injecting and recirculating reactive components; a duct for delivering the mixture, communicating with the mixing chamber; a valve body with recirculation longitudinal slots, sliding into the mixing chamber between a backward position in which it clears the inlet openings and enables to mix components, and an advanced position, in which the slots put inlet openings in communication with outlet openings for recirculating the reactive components; the delivery duct, of the self-cleaning type, is a single-piece tubular element, removably fastened—by means of fixing members—and can be inserted into a hole transversal to the mixing chamber passing through the head-body; the tubular element has an intermediate transversal hole aligned with the mixing chamber with a diameter greater than a diameter of the mixing chamber for compensating, while assembling, for possible inevitable errors of alignment and mutual positioning due to processing tolerances of the parts to be coupled and for avoiding protrusions of the walls of the transversal hole from forming inwardly of the mixing chamber of the head-body, protrusions that might interfere with the end the walls of the valve member during the movement in the hole passing through the thickness of the tubular element until the end of said hole leading into the delivery chamber and that extends the mixing chamber to the wall of the self-cleaning delivery duct. Between the tubular element and the pass-through hole in the head-body a gap is defined, i.e. a certain coupling tolerance with a clearance between the tubular element and the hole, enabling to insert and remove the tubular element into/from the pass-through hole. Sealing elements prevent the leakage of polymeric mixture and lubricant liquid in the aforesaid gap; analogously, between the surface of the cap and the second hole—obtained in a opposite position with respect to the hole—a respective gap with clearance is defined where an elastic or elasto-plastic sealing is interposed; the valve member, in the advanced and penetrating position into the hole of the tubular element, is separated therefrom by a gap, with a sealing member interposed therebetween; the gap prevents the metal-on-metal contact on the front part of the valve element when it enters into the intermediate hole; generally, thanks to gaps, the assembly and coupling of respective components is eased, facilitating the centering and mutual angular positioning thereof and avoiding undesired interferences; the sealing elements prevent the leakage of polymeric mixture and possible lubricant liquid in the respective aforesaid gaps.