Machine tool and control apparatus of the machine tool

Patent metadata

Field	Value
Publication number	US-2017246718-A1
Application number	US-201515506793-A
Country	US
Kind code	A1
Filing date	Aug 27, 2015
Priority date	Aug 29, 2014
Publication date	Aug 31, 2017
Grant date	—

Abstract

In a machine tool and a control apparatus thereof, a repetitive movement unit is configured so that the cutting tool performs one repetitive movement with respect to multiple relative rotations between the workpiece and the cutting tool and so that a rotation angle of the relative rotation between the workpiece and the cutting tool during relative movement at a second speed is smaller than a rotation angle of the relative rotation during relative movement at a first speed in one repetitive movement. This configuration limits degradation of machining efficiency when the cutting tool machines the workpiece by performing one repetitive movement with respect to multiple relative rotations between the workpiece and the cutting tool.

First claim

1 . A machine tool comprising:
a workpiece holding unit to hold a workpiece; a tool rest to hold a cutting tool for cutting the workpiece; a feeding unit to feed the cutting tool toward the workpiece in a predetermined feeding direction via relative movement between the workpiece holding unit and the tool rest; a repetitive movement unit to repetitively move the workpiece holding unit and the tool rest in a mutually relative manner by repeating the relative movement in the feeding direction at a first speed and a second speed that are mutually different; and a rotating unit to relatively rotate the workpiece and the cutting tool; wherein the machine tool is capable of machining the workpiece via the relative rotation between the workpiece and the cutting tool and via the feeding of the cutting tool toward the workpiece with the repetitive movement; and wherein the repetitive movement unit is configured so that the cutting tool performs one repetitive movement with respect to multiple relative rotations between the workpiece and the cutting tool and so that a rotation angle of the relative rotation during the relative movement at the second speed is smaller than a rotation angle of the relative rotation during the relative movement at the first speed in one repetitive movement.

2 . The machine tool according to claim 1 ,
wherein the first speed is set faster than the second speed.

3 - 4 . (canceled)

5 . The machine tool according to claim 1 , wherein
a reference angle position is set on the basis of a rotation angle position of the relative rotation at which a cutting work position of the relative movement at the first speed and a cutting work position of the relative movement at the second speed intersect with each other; and the repetitive movement unit is configured so that, during one rotation from the reference angle position after the relative movement at the first speed is performed for the length of a predetermined number of the relative rotations from the reference angle position, the relative movement at the first speed switches to the relative movement at the second speed and the cutting work position of the relative movement at the second speed reaches the cutting work position of the relative movement at the first speed to complete one repetitive movement.

6 . A control apparatus of a machine tool comprising:
a workpiece holding unit to hold a workpiece; a tool rest to hold a cutting tool for cutting the workpiece; a feeding unit to feed the cutting tool toward the workpiece in a predetermined feeding direction via relative movement between the workpiece holding unit and the tool rest; a repetitive movement unit to repetitively move the workpiece holding unit and the tool rest in a mutually relative manner by repeating the relative movement in the feeding direction at a first speed and a second speed that are mutually different; and a rotating unit to relatively rotate the workpiece and the cutting tool; wherein the machine tool is capable of machining the workpiece via the relative rotation between the workpiece and the cutting tool and via the feeding of the cutting tool toward the workpiece with the repetitive movement; and wherein the repetitive movement unit is configured so that the cutting tool performs one repetitive movement with respect to multiple relative rotations between the workpiece and the cutting tool and so that a rotation angle of the relative rotation during the relative movement at the second speed is smaller than a rotation angle of the relative rotation during the relative movement at the first speed in one repetitive movement.

Assignees

• Citizen Watch Co Ltd
• Citizen Machinery Co Ltd

Inventors

• Sannomiya Kazuhiko
• Matsumoto Hitoshi
• Imasaki Nobuyoshi

Classifications

• B23B1/00 Primary

  Methods for turning or working essentially requiring the use of turning-machines; Use of auxiliary equipment in connection with such methods · CPC title

• B23B25/02

  Arrangements for chip-breaking in turning-machines (on cutting tools B23B27/22) · CPC title

• G05B2219/49355

  Machine flat surface on rotating workpiece, rotate tool inverse direction · CPC title

• G05B19/416

  characterised by control of velocity, acceleration or deceleration (G05B19/19 takes precedence) · CPC title

• B23Q15/013 Primary

  Control or regulation of feed movement (B23Q15/12 takes precedence) · CPC title