Patent · US Expired

Transfer molding process and an apparatus for the same

US4954301A · kind A · utility

20Cited by
11References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 12, 1989
Grant dateSep 4, 1990
Priority date
Expiry dateJul 12, 2009

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29C45/02
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A transfer molding process and an apparatus for carrying out the same for sealing electronic devices, such as semiconductor devices, in a resin by driving a plunger downward in a pot to inject the resin into a mold. In injecting a resin into a mold by driving the plunger downward, the rotary motion of the output shaft of an electric motor is converted into a linear motion to drive the plunger downward, the downward displacement of the plunger from the initial position is detected, and pressure applied to the plunger is varied according to the displacement of the plunger. Thus, the transfer molding process and the apparatus for carrying out the same reduces defects, such as voids and incompletely filled parts, in the resin-sealed device, and prevents burrs and the deformation of the insert during the transfer molding operation.

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