The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 29, 1984
Filed:
Feb. 10, 1982
Michio Ishikawa, Nagoya, JP;
Kiyoshi Sasaki, Nagoya, JP;
Brother Kogyo Kabushiki Kaisha, Nagoya, JP;
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.