Patent · US Expired

Hybrid injection molding machine

US6089849A · kind A · utility

20Cited by
12References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 27, 1998
Grant dateJul 18, 2000
Priority date
Expiry dateFeb 27, 2018

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29C2945/76943
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

An energy efficient general purpose injection molding employs a hydraulic drive for injection and clamp machine functions and an electric drive for screw recovery. Both drives use AC "squirrel cage" induction motors under vector control. Speed command signals for the vector controls are generated by the machine's controller utilizing state transition and predictive signal techniques to account for motor and motor/pump response latencies. Hydraulic drive efficiency is improved by varying motor speed/pump output to match cycle requirements to retain hydraulic drive advantages for mold clamp and injection functions while improving the electric drive performance for screw recovery.

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