Method of detecting dust and method of preventing erroneous determination of dust detection
US8969751B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 30, 2009 |
| Grant date | Mar 3, 2015 |
| Priority date | — |
| Expiry date | Sep 30, 2031 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23K11/256
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method of detecting dust includes: a first step of monitoring a resistance value welding and determining if a variation amount of the resistance value per unit time is equal to or more than a first threshold; a second step of monitoring the resistance value after the first step and determining if a variation amount of this resistance value per unit time is equal to or less than a second threshold; a third step of determining if a difference value between a resistance value for calculating the variation amount equal to or more than the first threshold and a resistance value for calculating the variation amount determined equal to or less than the second threshold is equal to or more than a third threshold; and a fourth step of determining that dust is generated when the difference value is equal to or more than the third threshold.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.