Controller for gear cutting machine

Patent metadata

Field	Value
Publication number	US-11003168-B2
Application number	US-201916588038-A
Country	US
Kind code	B2
Filing date	Sep 30, 2019
Priority date	Oct 2, 2018
Publication date	May 11, 2021
Grant date	May 11, 2021

Abstract

Provided is a controller for controlling a gear cutting machine having a plurality of axes, the controller including an axis information storage unit configured to store data related to control of the plurality of axes during machining, and a disturbance component identification unit configured to identify a component of disturbance with respect to the plurality of axes using the data stored by the axis information storage unit and measurement results of machining accuracy of a workpiece machined by the cutting machine.

First claim

The invention claimed is:

1. A controller for controlling a gear cutting machine having a plurality of axes, the controller comprising:
an axis information storage unit configured to store data related to control of the plurality of axes during machining, and
a disturbance component identification unit configured to identify a component of disturbance with respect to the plurality of axes by using the data stored by the axis information storage unit and measurement results, received from measurement equipment coupled to the disturbance component identification unit, of machining accuracy of a workpiece machined by the gear cutting machine.

2. The controller according to claim 1 , further comprising a correction selection unit configured to select, in accordance with the identified component of the disturbance, a correction to be applied to the control of the plurality of axes in order to cancel the disturbance, from among a plurality of types of corrections stored in advance.

3. The controller according to claim 2 , wherein the correction selection unit selects, from among the plurality of axes, an axis to which the correction is applied in accordance with the identified component of the disturbance.

4. The controller according to claim 2 , wherein the disturbance component identification unit identifies a frequency of the component of the disturbance, and
the correction selection unit selects a different type of correction between a case where the frequency of the component of the disturbance is proportional to a rotational frequency of one of the plurality of drive axes and a case where the frequency of the component of the disturbance is proportional to the rotational frequency of none of the plurality of drive axes.

5. The controller according to claim 1 , wherein the data includes one of position deviation of each of the plurality of axes and a synchronization error between two of the plurality of axes, and
the disturbance component identification unit identifies the component of the disturbance by calculating an undulation in a tooth trace direction on a tooth surface of the workpiece based on one of the position deviation and the synchronization error, and comparing the calculated undulation in the tooth trace direction with an undulation in the tooth trace direction on the tooth surface of the workpiece obtained by measuring the machined workpiece.

6. The controller according to claim 1 , wherein the data includes one of position deviation of each of the plurality of axes and a synchronization error between two of the plurality of axes, and
the disturbance component identification unit identifies the component of the disturbance by comparing a frequency component appearing on one of the position deviation and the synchronization error with a frequency component calculated from a number of undulations in a tooth profile direction on a tooth surface of the workpiece obtained by measuring the machined workpiece.

7. The controller according to claim 1 , wherein the data includes one of position deviation of each of the plurality of axes and a synchronization error between two of the plurality of axes, and
the disturbance component identification unit identifies the component of the disturbance by comparing a frequency component appearing on one of the position deviation and the synchronization error with a frequency component calculated from a number of undulations appearing on a single pitch error within a rotation of a gear obtained by measuring the machined workpiece.

Assignees

• Fanuc Corp

Inventors

• Hashimoto Shoutarou
• Toyozawa Yukio

Classifications

• B23F9/025

  with a face-mill-type, i.e. cup-shaped, grinding wheel · CPC title

• B23F9/10

  with a face-mill · CPC title

• B23F23/00

  Accessories or equipment combined with or arranged in, or specially designed to form part of, gear-cutting machines (accessories or equipment not restricted to gear-cutting machines B23Q) · CPC title

• B23F23/006 Primary

  Equipment for synchronising movement of cutting tool and workpiece, the cutting tool and workpiece not being mechanically coupled · CPC title

• G05B19/404 Primary

  characterised by control arrangements for compensation, e.g. for backlash, overshoot, tool offset, tool wear, temperature, machine construction errors, load, inertia (G05B19/19, G05B19/41 take precedence) · CPC title