Patent · US Expired

Five layer injection molding apparatus having four position valve member actuating mechanism

US6074191A · kind A · utility

20Cited by
1References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 24, 1997
Grant dateJun 13, 2000
Priority date
Expiry dateNov 24, 2017

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29K2105/253
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

Valve gated multi-cavity injection molding apparatus for five layer molding having actuating mechanisms for reciprocating elongated valve members between four different positions. Each actuating mechanism has a front and a rear aligned cylinders, a first piston connected to the head of one of the valve members in the front cylinder and second and third pistons in the rear cylinder. The third piston has a stem portion which extends forwardly through the second piston into the front cylinder. Hydraulic pressure from four hydraulic lines connected to each actuating mechanism reciprocates each elongated valve member between the different positions. In the first closed position, the front end of the valve member is seated in the gate. In the second position, the front end of the valve member is retracted sufficiently to allow an initial amount of PET to flow from an outer annular melt channel through the gate. Then the valve member is retracted further to a third position to allow simultaneous flow of the PET and a barrier material from an inner annular melt channel. Then the valve member is retracted to a fully open position which allows the simultaneous flow of PET from a central melt…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.