Patent · US Expired

Apparatus for manufacturing an injection-molded product having a partly thin portion

US4820149A · kind A · utility

21Cited by
7References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 7, 1987
Grant dateApr 11, 1989
Priority date
Expiry dateDec 7, 2007

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29C2045/569
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

An apparatus for injection molding a product having a partly thin portion includes a molding die including a male die and a female die for defining a cavity having a volume larger than a volume of the product. A gate is provided to permit molten resin material from an injection molding machine to be injected into the cavity. A slide block disposed in either the male die or the female die has in cross section a dimension corresponding to a dimension of the thin portion of the product. The slide block is movable between a retracted position where the volume of the cavity is substantially maintained and an advanced position to project into the cavity to form the thin portion. A drive is provided for moving the slide block to the advanced position before the resin material injected into the cavity is solidified. A hollow space formed in the molding die and communicating with the cavity permits an excess of the resin material to be discharged from the cavity into the hollow space during the advance of the slide block. A closure member is fitted in the hollow space for normally closing the same and is coupled to a spring for urging the closure member to the retracted position and a power…

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