초록 ▼

An injection-molding apparatus has a nozzle extending along an axis and formed with an axially forwardly opening outlet, an annular port fixed immediately axially behind or upstream of the outlet, and a central axially forwardly opening port axially fixed behind the annular outlet. Respective plasti

An injection-molding apparatus has a nozzle extending along an axis and formed with an axially forwardly opening outlet, an annular port fixed immediately axially behind or upstream of the outlet, and a central axially forwardly opening port axially fixed behind the annular outlet. Respective plastifiers for feeding respective plastified synthetic resins, normally thermoplastics, are connected to the respective ports. An axially displaceable valve body in the nozzle is displaceable from a fully forward position blocking both of the ports, through a partially back position blocking only the central port, to a fully back position clear of both of the ports. Thus in the fully forward position no resin can enter the nozzle, in the partially back position resin can enter the nozzle only from the annular port, and in the fully back position resins can enter the nozzle through both of the ports.

대표청구항 ▼

An injection-molding apparatus for forming objects of two different resins, said apparatus comprising: a nozzle extending along an axis and having a tubular and axially centered outer nozzle part forming an axially forwardly opening outlet and a tubular and axially centered inner nozzle part fixed a

An injection-molding apparatus for forming objects of two different resins, said apparatus comprising: a nozzle extending along an axis and having a tubular and axially centered outer nozzle part forming an axially forwardly opening outlet and a tubular and axially centered inner nozzle part fixed axially behind said outer part and forming therewith an annular port immediately axially behind said outlet and formed with a central axially forwardly opening port axially fixed behind and surrounded by said annular port; respective plastifying means for feeding respective and different plastified synthetic resins under pressure to said ports; and an axially displaceable valve needle in said nozzle and snugly fittable in said central port, said needle being displaceable relative to both of said nozzle parts from a fully forward position extending axially forward through said central port past said inner nozzle part into engagement with said outer nozzle part at said outlet and blocking both of said ports, through a partially back position in and blocking only said central port, to a fully back position clear of both of said ports, whereby in said fully forward position no resin can enter said nozzle, in said partially back position resin can enter said nozzle only from said annular port, and in said fully back position resins can enter said nozzle through both of said ports.