Patent · US Expired

Apparatus for controlling the distance of a melting electrode from the surface of the melted material in a vacuum arc furnace

US4797897A · kind A · utility

8Cited by
8References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 10, 1987
Grant dateJan 10, 1989
Priority date
Expiry dateAug 10, 2007

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P10/25
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

Apparatus for controlling the distance of a melting electrode from the surface of melted material in a vacuum arc furnace which uses short circuits caused by the droplets between the melting electrode and the surface of the melted material as a control criterion. The short circuits occurring within a given period of time--the so-called droplet rate--are determined and supplied to an averager which is connected with a controller that controls an electric driving mechanism for the melting electrode. According to the invention, the controller is responsive to a signal representing the difference between the reciprocal value of the droplet rate signal formed by the averager and a desired time, this desired time being equal to the desired average time between two consecutive droplet short circuits.

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