Cutting tool retreat and return for workpiece protection upon abnormality occurrence in a preprogrammed machine tool
US4442493A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 1981 |
| Grant date | Apr 10, 1984 |
| Priority date | — |
| Expiry date | Jun 30, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T408/175
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A numerically controlled (NC) machine tool has apparatus for automatically positioning and feeding a cutting tool to follow a programmably predetermined path. Sensing devices are provided to detect when the cutting tool suffers an abnormality, such as becoming dull or chipped. The feed devices of the NC machine tool are then commanded, by an arithmetic unit having a memory and by an NC command generating unit, to automatically retreat the cutting tool. It retreats, without interference with the workpiece, to a first position, parametrically determined by the shape and size of the workpiece, cutting tool data for the abnormality, completion and tool exchange positions, and by the nature of the machining operation. This retreat location is a position at which the cutting tool may be replaced. After replacement of the cutting tool, the cutting tool is automatically returned, via the first position, to a second position from which the machining is resumed. The second position is determined by the arithmetic means to provide for repeated machining of a portion of the surface of the workpiece leading to the position at which the abnormality was sensed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.