MACHINING STATUS MONITORING METHOD AND MACHINING STATUS MONITORING APPARATUS

• US 20100063616A1
• Filed: 09/04/2009
• Published: 03/11/2010
• Est. Priority Date: 09/05/2008
• Status: Active Grant

• Current Assignee: MORI Seiki Company Limited (Dmg Mori Co., Ltd.)
• Original Assignee: MORI Seiki Company Limited (Dmg Mori Co., Ltd.)
• Inventors: Mori, Masahiko, Fujishima, Makoto, Tian, Xiaodong, Zhao, Bingyan, Jin, Zhe
• Granted Patent: US 8,180,477 B2
• Time in Patent Office: Days
• US Class Current: 700/160
• CPC Class Codes: G05B 19/406 characterised by monitoring or safety G05B19/19 takes precedence
• CPC Class Codes: G05B 2219/37563 Ccd, tv camera
• CPC Class Codes: G05B 2219/50064 Camera inspects workpiece for errors, correction of workpiece at desired position

Abstract

A machining status monitoring apparatus is provided on a machine tool, and has an actual CCD camera for imaging the tool and the workpiece and generating actual two-dimensional image data thereof, a virtual image generating section having a virtual CCD camera corresponding to the actual CCD camera, in which the tool and workpiece of three-dimensional model are imaged by the virtual CCD camera and virtual two-dimensional image data thereof are generated, and a display control section for receiving from a control device of the machine tool, information relating to the coolant supply state and checking whether coolant is being supplied to the contact portion of the tool and the workpiece, and displaying on a display device actual two-dimensional image data when coolant is not being supplied and displaying on the display device virtual two-dimensional image data when coolant is being supplied.

Claims

1. A machining status monitoring method in a machine tool having tool holding means for holding a tool, workpiece holding means for holding a workpiece, drive means for operating one or both of the holding means, supply means for supplying coolant to a contact portion of the tool and the workpiece, control means for controlling the operation of the supply means, and controlling the operation of the drive means based on an operation command relating to one or both of the holding means, and display means for displaying image data, the machining status monitoring method comprising:

an actual image generating step of imaging the tool and the workpiece at a certain time interval by means of at least one imaging means from a predetermined view point, and in turn generating actual two-dimensional image data thereof;

a model updating step in which, based on the operation command and data on three-dimensional models of the holding means, tool and workpiece, model data of the holding means, tool and workpiece when one or both of the holding means are operated according to the operation command are generated and the model data thereof are updated;

a virtual image generating step of generating virtual two-dimensional image data of the tool and workpiece based on the model data updated in the model updating step, the virtual image data generating step in which a three-dimensional space is virtually set;

in this virtual three-dimensional space, the three-dimensional models of the tool and workpiece are arranged and imaging means having the same condition as that of the actual imaging means is virtually set and arranged; and

virtual two-dimensional image data which are assumed to be obtained when the tool and the workpiece are imaged at a certain time interval by the virtual imaging means from the same view point as that of the actual imaging means are generated in turn; and

an image display step of checking whether coolant is being supplied to the contact portion of the tool and the workpiece based on information relating to the coolant supply state, and displaying on the display means actual two-dimensional image data generated by the actual imaging means when coolant is not being supplied, and displaying on the display means virtual two-dimensional image data generated in the virtual image generating step when coolant is being supplied.

2. A machining status monitoring apparatus provided on a machine tool having tool holding means for holding a tool, workpiece holding means for holding a workpiece, drive means for operating one or both of the holding means, supply means for supplying coolant to a contact portion of the tool and the workpiece, control means for controlling an operation of the supply means, and controlling an operation of the drive means based on an operation command relating to one or both of the holding means, and display means for displaying image data, the machining status monitoring apparatus comprising:

at least one actual imaging means for imaging the tool and the workpiece at a certain time interval from a predetermined view point, and in turn generating actual two-dimensional image data thereof;

model data updating means for, after receiving the operation command from the control means, based on the received operation command and data on three-dimensional models of the holding means, tool and workpiece, generating model data of the holding means, tool and workpiece which are in a state in which one or both of the holding means are operated according to the operation command, and updating the model data thereof;

virtual image generating means for generating virtual two-dimensional image data of the tool and workpiece based on the model data updated by the model data updating means, the virtual image generating means in which a three-dimensional space is virtually set;

in this virtual three-dimensional space, the three-dimensional models of the tool and workpiece are arranged and imaging means having the same condition as that of the actual imaging means is virtually set and arranged; and

virtual two-dimensional image data which are assumed to be obtained when the tool and the workpiece are imaged at a certain time interval by the virtual imaging means from the same view point as that of the actual imaging means, are generated in turn; and

display control means for, after receiving from the control means information relating to the state of the supply of coolant by the supply means, checking whether coolant is being supplied to the contact portion of the tool and the workpiece based on the received information, and displaying on the display means actual two-dimensional image data generated by the actual imaging means when coolant is not being supplied, and displaying on the display means virtual two-dimensional image data generated by the virtual image generating means when coolant is being supplied.

3. The machining status monitoring apparatus according to claim 2, wherein

the machining status monitoring apparatus has sectional image generating means for generating sectional image data including the tool and a sectional shape appearing when at least the workpiece is cut along a plane passing through the distal end of the tool based on the model data updated by the model data updating means,

the virtual image generating means is configured so that virtual imaging means having the same conditions as those of a plurality of the actual imaging means which image the tool and the workpiece from different view points are set as many as the actual imaging means, and virtual two-dimensional image data which are assumed to be obtained when the tool and the workpiece represented by three-dimensional model are imaged at a certain time interval by the virtual imaging means from the same view points as those of the actual imaging means are generated in turn, and

the display control means is configured to, based on virtual two-dimensional image data generated by the virtual image generating means, check whether the distal end of the tool is hidden by the workpiece in all of the virtual two-dimensional images, and display on the display means sectional image data generated by the sectional image generating means when determining that the distal end of the tool is hidden in all of the virtual two-dimensional images.

4. The machining status monitoring apparatus according to claim 3, wherein

the sectional image generating means is configured to set a plane which passes through the distal end of the tool and is perpendicular to the optical axis of any one of the actual imaging means as a cutting plane in generating the sectional image data.

5. The machining status monitoring apparatus according to claim 3, wherein

in a case where the machine tool is a lathe and the workpiece holding means is a spindle, the sectional image generating means is configured to set a plane passing through the distal end of the tool and the axis of the spindle as a cutting plane in generating the sectional image data.