Machine tool
US4451187A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 10, 1982 |
| Grant date | May 29, 1984 |
| Priority date | — |
| Expiry date | Feb 10, 2002 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T409/30728
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A machine tool comprising a rotary drive unit rotating a tool or workpiece, a load torque detecting device disposed between the rotary drive unit and the tool or workpiece rotated thereby, a linear drive unit moving one of the tool and the workpiece toward and away from the other, a main start switch for actuating the rotary drive unit, and a control device. The control device starts the rotary drive unit upon actuation of the main start switch; starts the linear drive unit to allow the tool to initiate a cutting operation on the workpiece when a variation in a load torque within a given period detected by the detecting device has decreased down to a first preset limit; and reverse the operating direction of the linear drive unit to interrupt the cutting operation if and when a difference between a load torque currently detected by the detecting device after the start of the linear drive unit and a load torque detected by the detecting device after the decrease of said variation to the first preset limit and before the initiation of the cutting operation, has exceeded a second preset limit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.