Patent · US Expired

Mold die

US4126292A · kind A · utility

38Cited by
2References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 28, 1977
Grant dateNov 21, 1978
Priority date
Expiry dateJun 28, 1997

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29C45/2704
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A mold die including two or more cavities shaped to profile the configuration of mold products, a pot serving as a lead-in portion for resin of a tablet-form, or a sprue serving as a lead-in portion for molten resin, a runner leading to the pot or sprue, and gates branching from the runner and leading to respective cavities, the aforesaid gates having given convergent slopes at their exits to the cavities. The cross-sectional area of the runner is progressively decreased in the direction away from the pot or sprue, and the convergent slopes of the gates are progressively increased in the direction away from the pot or sprue, in a manner that the sum of a pressure drop in a runner portion and a pressure drop in a gate portion may be made equal for each of the cavities, thereby minimizing a difference in timing of resin to arrive respective cavities, and rendering the velocity of resin flowing into respective cavities equal to one another.

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