Machine tool

• US 6,479,960 B2
• Filed: 02/14/2001
• Issued: 11/12/2002
• Est. Priority Date: 07/10/2000
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation), Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Loennqvist, Peter, Iwasaki, Takashi, Nakai, Satoru
• Primary Examiner(s): Nappi, Robert E.
• Assistant Examiner(s): SMITH, TYRONE W
• Application Number:
  US09/782,159
• Publication Number:
  US 20020003415A1
• Time in Patent Office: 636 Days
• Field of Search: 318/568.1, 318/568.12, 318/569, 318/570, 318/573, 318/568.22, 318/560, 364/474
• US Class Current: 318/569
• CPC Class Codes: G05B 19/4065 Monitoring tool breakage, life or condition
• CPC Class Codes: G05B 2219/37559 Camera, vision of tool, compute tool center, detect tool wear

Abstract

A machine tool includes a tool (a drill or the like having a diameter of 2 mm or less), a camera (artificial retina chip or the like) which acquires an image of the tool, and an image processor which determines whether the tool is faulty based on the image acquired by the camera.

Claims

1. A machine tool comprising:

a plurality of tools for working an object, one of said plurality of tools being employed in working the object;

a photographing unit including an artificial retina chip which acquires an image of said tool employed in working the object and processes the image acquired; and

a determination unit which determines whether said tool is faulty based on the image acquired and processed by said photographing unit, wherein

said determination unit includes a respective table for each type of said plurality of tools, each table describing areas of an image acquired, with respect to the type of tool, for determining whether said tool of the acquired image is faulty, feature extraction processing to be performed by said photographing unit, and determination processing to be performed by said determination unit, including threshold values used in the determination processing for determining whether said tool of the acquired image is faulty,

said determination unit instructs said photographing unit regarding processing of the image acquired of said tool with respect to the areas of the image acquired and features for the feature extraction processing, and

said photographing unit outputs the image acquired of said tool to said determination unit, in a compressed format, after the feature extraction processing of the areas specified in the corresponding table stored in said determination unit.

2. The machine tool according to claim 1, wherein said tool is a drill having a diameter not exceeding 0.2 mm.

3. The machine tool according to claim 2, further comprising a photographing unit cleaning unit which cleans said photographing unit before said photographing unit acquires the image.

4. A machine tool comprising:

a plurality of tools for working an object, one of said plurality of tools being employed in working the object;

a plurality of photographing units which acquire respective images of said tool employed in working the object, each of said photographing units having an artificial retina chip which acquires one of the respective images of said tool, said plurality of photographing units producing a stereo image of said tool from the respective images; and

a determination unit which determines whether said tool is faulty based on the stereo image produced by said plurality photographing units, wherein

said determination unit includes a respective table for each type of said plurality of tools, each table describing areas of an image acquired, with respect to the type of tool, for determining whether said tool of the acquired stereo image is faulty, feature extraction processing to be performed by said photographing unit, and determination processing to be performed by said determination unit, including threshold values used in the determination processing for determining whether said tool of the acquired stereo image is faulty,

said determination unit instructs said photographing unit regarding processing of the stereo image acquired of said tool with respect to the areas of the stereo image acquired and features for the feature extraction processing, and

said photographing unit outputs the stereo image acquired of said tool to said determination unit, in a compressed format, after the feature extraction processing of the areas specified in the corresponding table stored in said determination unit.

5. A machine tool comprising:

a plurality of tools for working an object, one of said plurality of tools being employed in working the object;

a photographing unit including an artificial retina chip which acquires an image of said tool employed in working the object and processes the image acquired;

a tool cleaning unit which cleans said tool before said photographing unit acquires the image of said tool; and

a determination unit which determines whether chips produced by working of the object by said tool are twined around said tool based on the image acquired and processed by said photographing unit, wherein

said determination unit includes a respective table for each type of said plurality of tools, each table describing areas of an image acquired, with respect to the type of tool, for determining whether said tool of the acquired image is faulty, feature extraction processing to be performed by said photographing unit, and determination processing to be performed by said determination unit, including threshold values used in the determination processing for determining whether said tool of the acquired image is faulty,

said determination unit instructs said photographing unit regarding processing of the image acquired of said tool with respect to the areas of the image acquired and features for the feature extraction processing, and

said photographing unit outputs the image acquired of said tool to said determination unit, in a compressed format, after the feature extraction processing of the areas specified in the corresponding table stored in said determination unit.