Detecting machine tool set-up errors

US4555698A · kind A · utility

Assignee

• British Aerospace Public Limited Co. · GB

Inventors

• Frederick G. Clark · Naples, US
• Colin Moore · Warton, GB

Key dates

• Filing date: May 11, 1982
• Grant date: Nov 26, 1985
• Expiry date: May 11, 2002

Classification

• Technology area (CPC G): Physics
• CPC primary: G05B19/4015
• WIPO field: Control
• WIPO sector: Instruments

Abstract

A tool setting-aid comprising an anodized aluminum "button" and a support therefor is set up at a predetermined datum position on the worktable of a computer controlled machine tool, the machine program including a check cycle which sends the cutting tool around and over the button or, if the tool is oversize or set wrongly, into contact with the button. The button is supplied with electrical current via a cable having a resistor coupled to the button end thereof by an electronic detector circuit which includes a sensor for detecting current increase due to contact between button and cutting tool and a sensor for sensing interruption of such current due to cable breakage or a failure to properly connect it to the setting-aid.