Patent · US Expired

Mold-clamping mechanism for injection-molding machine

US4017236A · kind A · utility

26Cited by
6References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 26, 1975
Grant dateApr 12, 1977
Priority date
Expiry dateNov 26, 1995

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S425/221
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A clamping mechanism, effective to press a movable platen against a fixed platen in a terminal phase of a mold-closing stroke of an injection-molding machine, comprises a series of coaxial annular pistons received with progressively larger clearances in respective inner peripheral grooves of a stationary housing linked by tie rods with the fixed platen. The pistons, which can be interconnected by elastic bolts, bear upon a mounting frame, slidable along the tie rods, supporting a pair of laterally withdrawable shutters which in their retracted position give passage to a tubular thrust member coaxially surrounding a plunger secured to that thrust member and to the movable platen. The opposite end of the plunger carries a piston head received, within the housing, in a central driving cylinder to which hydraulic fluid can be admitted from either end for advancing or retracting the movable platen in a mold-closing or a mold-opening stroke. In a forward position of the movable platen, the tubular thrust member just clears the shutters which are then moved toward each other into a working position behind that member whereupon fluid is admitted to the housing grooves for pressurizing the …

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