Tool changing method and tool changer

Patent metadata

Field	Value
Publication number	US-2018222002-A1
Application number	US-201515748459-A
Country	US
Kind code	A1
Filing date	Jul 29, 2015
Priority date	Jul 29, 2015
Publication date	Aug 9, 2018
Grant date	—

Abstract

This tool exchange device for a machine tool uses an exchange arm to exchange tools between a processing area and a tool accommodation area which are partitioned by a partition wall provided with an opening and a shutter capable of opening and closing the opening. In the tool exchange device, an imaging device is used to capture an image of a tool in the tool accommodation area, the length of the tool is calculated from the captured image of the tool, the opening width of the shutter is determined in accordance with the length of the tool, and the shutter is opened to the determined opening width.

First claim

1 . A tool changing method for a machine tool configured to change tools by a changing arm between a machining space and a tool storage space, characterized by:
an image capturing step of capturing an image of a tool with an image capturing device in a took storage space; a calculating step of calculating a length of the tool based on the image captured in the image capturing step; an control parameter determining step of determining an control parameter for the mechanical operation occurring with tool change, based on the length of the tool; and a tool changing step of changing the tools between the machining space and the tool storage space by carrying out the mechanical operation occurring with the tool change based on the control parameter.

2 . The tool changing method of claim 1 , wherein the tool changing step includes a shutter opening and closing step, wherein an opening width for the shutter is determined based on the length of the tool as the control parameter for the mechanical operation occurring with the tool change in the control parameter determining step, wherein the shutter is opened to the determined opening width in the shutter opening and closing step.

3 . The tool changing method of claim 2 , wherein the length of a tool attached to a spindle and the length of a tool to be changed for the next machining process with the tool attached to the spindle when a machining process with the tool is completed are compared with each other, whereby the opening width of the shutter is determined based on the length of the longer one of the tools.

4 . The tool changing method of claim 1 , wherein the tool changing step includes a workpiece retracting step of moving the tool and a workpiece relative to and away from each other, wherein the relative position between the tool and the workpiece where the tool does not interfere with the workpiece during the tool change as the control parameter for the mechanical operation occurring with the tool change based on the length of the tool in the control parameter determining step, wherein the workpiece retracting step includes moving to the determined position.

5 . The tool changing method of claim 1 , wherein an image of a tool which is detached from a spindle, when the tool is conveyed to the tool storage space after the machining process with the tool attached to the spindle is completed, and the tool is detached from the spindle, and before a machining process is started with a tool newly attached to the spindle, wherein the image is compared with an image of the tool captured before the tool is attached to the spindle, so as to determine whether or not the is damaged based on the difference between the two images, whereby an alert is generated and the initiation of the machining process is abandoned if a damage is found, and a machining process is started if no damage is found.

6 . A tool changer for a machine tool configured to change tools by a changing arm between a machining space and a tool storage space, characterized by:
an image capturing device for capturing an image of a tool in a took storage space; a control device configured to calculate a length of the tool based on the image captured in the image capturing device, to determine an control parameter for the mechanical operation occurring with tool change, based on the length of the tool, and to control the mechanical operation occurring with tool change; and a changing arm configured to change the tools between the machining space and the tool storage space.

7 . The tool changer of claim 6 , further comprising a shutter dispose between the machining space and the tool storage space,
wherein the control device determines an opening width for the shutter based on the length of the tool as the control parameter for the mechanical operation occurring with the tool change, and to control the shutter to open to the determined opening width.

8 . The tool changer of claim 7 , wherein the control device compares the length of a tool attached to a spindle and the length of a tool to be changed for the next machining process with the tool attached to the spindle when a machining process with the tool is completed so as to determine the opening width of the shutter based on the length of the longer one of the tools.

9 . The tool changer of claim 6 , wherein the control device determines a shunt position relative to the tool and the workpiece where the tool does not interfere with the workpiece during the tool change as the control parameter for the mechanical operation occurring with the tool change based on the length of the tool, and controls to move the workpiece to the determined shunt position.

10 . The tool changer of claim 9 , wherein the control device captures an image of a tool which is detached from a spindle, when the tool is conveyed to the tool storage space after the machining process with the tool attached to the spindle is completed, and the tool is detached from the spindle, and before a machining process is started with a tool newly attached to the spindle, wherein the control device further compares the image with an image of the tool captured before the tool is attached to the spindle, so as to determine whether or not the is damaged based on the difference between the two images, whereby an alert is generated and the initiation of the machining process is abandoned if a damage is found, and a machining process is started if no damage is found.

Assignees

• Makino Milling Machine

Inventors

• Kasahara Tadashi

Classifications

• B23Q2003/1553

  by rectilinear projection · CPC title

• B23Q3/15513

  the tool being taken from a storage device and transferred to a tool holder by means of transfer devices · CPC title

• Y10T483/10

  Process · CPC title

• B23Q17/2461

  Length · CPC title

• Y10T483/138

  including means to monitor and control, i.e., adaptive machining · CPC title