Wire tension controlling method in a wire cut electric discharge machine
US5023420A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 1990 |
| Grant date | Jun 11, 1991 |
| Priority date | — |
| Expiry date | Mar 23, 2010 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23H7/104
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A wire tension controlling method in a wire cut electric discharge machine, capable of preventing occurrence of an excessive variation in a wire tension which may be caused by an abnormal operation of an electromagnetic powder brake upon start and release of application of the wire tension, and upon change of same. When the presence of a possibility of an actual wire tension being excessively changed is determined on the basis of the result of comparison between a present instructed wire tension and a new wire tension, a process of adding or subtracting an upper limit variation amount, set beforehand to such a value which may not cause the excessive variation in the wire tension, to or from the present target wire tension is repeatedly effected at predetermined intervals of a cycle until the target wire tension reaches the instructed wire tension, so that the electromagnetic powder brake effects a braking operation at an operation voltage corresponding to gradually changing target wire tension, so that the actual wire tension is gradually changed to the instructed wire tension.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.