Patent · US Expired

Method of estimating a life of ball screw included in electric injection molding machine and life estimating system

US6332355A · kind A · utility

5Cited by
3References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 18, 2000
Grant dateDec 25, 2001
Priority date
Expiry dateFeb 18, 2020

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H2057/012
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An injection unit including a heating barrel and an injection screw rotationally and axially movable and placed in the heating barrel is disposed on one side of a clamping mechanism for clamping a mold. The injection screw is driven and controlled for operation through a ball screw by an electric motor. Products, each of a moving speed of the ball screw and an operating current supplied to the electric motor in a unit time, are accumulated to calculate a total energy value indicating the amount of total energy supplied to the ball screw. A life energy value is predetermined on the basis of products, each of force generated by the ball screw and a moving speed of the ball screw. It is decided that a life of the ball screw has terminated when the total energy value A is equal to or greater than the life energy B (A.gtoreq.B).

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