Defect inspecting apparatus

Patent metadata

Field	Value
Publication number	US-9121833-B2
Application number	US-201213551014-A
Country	US
Kind code	B2
Filing date	Jul 17, 2012
Priority date	Jan 29, 2010
Publication date	Sep 1, 2015
Grant date	Sep 1, 2015

Abstract

A defect inspecting apparatus includes a first light source, a first image capture device that receives the reflection light emitted from the first light source and reflected by the outer peripheral surface of a lip part to grab the image of the outer peripheral surface of the lip part, a second light source, a second image capture device 8 that receives the reflection light emitted from the second light source and reflected by a load face to grab the image of the load face, a third light source, a third image capture device that receives the reflection light emitted from the third light source and reflected by a thread bottom face inspection zone 106 to grab the image of the thread bottom face inspection zone, and an inspection device for inspecting defects by processing the captured images grabbed by the first to third image capture devices.

First claim

The invention claimed is:

1. A defect inspecting apparatus for inspecting a defect on the outer peripheral surface of a pipe or tube in which in the end portion thereof, an external thread part and a lip part are provided in that order from the inside in the pipe or tube axis direction; a load face of the external thread part is inclined inwardly in the pipe or tube axis direction relative to the vertical plane perpendicular to the pipe or tube axis direction; and the lip part is tapered such that the dimension in the direction perpendicular to the pipe or tube axis direction decreases outwardly in the pipe or tube axis direction, the defect inspecting apparatus comprising:
a first light source for illuminating the outer peripheral surface of the lip part, in which the optical axis thereof is inclined through an angle A satisfying formula (1) outwardly in the pipe or tube axis direction relative to the vertical plane;
a first image capture device which is attached to the first light source so that the optical axis thereof is coaxial with the optical axis of the first light source, and receives the reflection light emitted from the first light source and reflected by the outer peripheral surface of the lip part to grab the image of the outer peripheral surface of the lip part;
a second light source for illuminating the load face;
a second image capture device which is attached to the second light source, and has the optical axis adjusted so that the reflection light emitted from the second light source and reflected by the load face to the direction inclined through an angle B satisfying formula (2) inwardly in the pipe or tube axis direction relative to the vertical plane can be received, and the reflection light is received to grab the image of the load face;
a third light source for illuminating a thread bottom face inspection zone ranging from a boundary part between the load face and the thread bottom face of the external thread part to a portion of the thread bottom face spaced apart inwardly by a predetermined distance from the boundary part in the pipe or tube axis direction;
a third image capture device which is attached to the third light source, and has the optical axis adjusted so that the reflection light emitted from the third light source and reflected by the thread bottom face inspection zone to the direction inclined through an angle C satisfying formula (3) inwardly in the pipe or tube axis direction relative to the vertical plane can be received, and the reflection light is received to grab the image of the thread bottom face inspection zone; and
an inspection device for inspecting defects on the outer peripheral surface of the lip part, on the load face, and in the thread bottom face inspection zone by processing the captured images grabbed by the first to third image capture devices:
a− 45≦ A≦a+ 45  (1)

b<B≦c   (2)

b<C≦d   (3)

a° being an angle (smaller than 90°) formed between the outer peripheral surface of the lip part and the pipe or tube axis direction in the cross section including the pipe or tube axis;
b° being an angle (smaller than 90°) formed between the load face and the vertical plane in the cross section including the pipe or tube axis;
c° being an angle (smaller than 90°) formed between a straight line and the vertical plane in the cross section including the pipe or tube axis, the straight line connecting the boundary part between the load face and the thread bottom face to a front end part of an insertion face of the external thread part, the insertion face connecting with an inside end part in the pipe or tube axis direction of the thread bottom face; and
d° being an angle (smaller than 90°) formed between a straight line and the vertical plane in the cross section including the pipe or tube axis, the straight line connecting an inside end part in the pipe or tube axis direction of the thread bottom face inspection zone to the front end part of the insertion face of the external thread part, the insertion face connecting with an inside end part in the pipe or tube axis direction of the thread bottom face.

2. The defect inspecting apparatus according to claim 1 , comprising:
a single light source member used as both of the second light source and the third light source;
a single image capture device used as both of the second image capture device and the third image capture device; and
a mirror the orientation of which can be changed over between an orientation at which the light emitted from the light source member is caused to enter the load face and the reflection light emitted from the light source member and reflected by the load face is received by the image capture device and an orientation at which the light emitted from the light source member is caused to enter the thread bottom face inspection zone and the reflection light emitted from the light source member and reflected by the thread bottom face inspection zone is received by the image capture device.

3. The defect inspecting apparatus according to claim 1 , wherein
the first image capture device is provided with a telecentric lens for receiving the reflection light reflected by the outer peripheral surface of the lip part;
the second image capture device is provided with a telecentric lens for receiving the reflection light reflected by the load face; and
the third image capture device is provided with a telecentric lens for receiving the reflection light reflected by the thread bottom face inspection zone.

4. The defect inspecting apparatus according to claim 1 , wherein
the first light source is a ring-shaped illuminator attached around the first image capture device;
the second light source is a ring-shaped illuminator which has an optical axis coaxial with the optical axis of the second image capture device and is attached around the second image capture device; and
the third light source is a ring-shaped illuminator which has an optical axis coaxial with the optical axis of the third image capture device and is attached around the third image capture device.

5. The defect inspecting apparatus according to claim 1 , comprising:
a fourth light source in place of the second light source and the third light source; and
a fourth image capture device in place of the second image capture device and the third image capture device, wherein
the fourth light source illuminates the load face and the thread bottom face inspection zone; and
the fourth image capture device is attached to the fourth light source, and has the optical axis adjusted so that the reflection light which is emitted from the fourth light source and reflected by the load face to the direction inclined through the angle C satisfying formula (3) inwardly in the pipe or tube axis direction relative to the vertical plane and the reflection light which is emitted from the fourth light source and reflected by the thread bottom face inspection zone to the direction inclined through the angle C satisfying formula (3) inwardly in the pipe or tube axis direction relative to the vertical plane can be received, and the reflection lights are received to grab the images of the load face and the thread bottom face inspection zone; and
the inspection device inspects defects on the outer peripheral surface of the lip part, on the load face, and in the thread bottom face inspection zone by processing the captured images grabbed by the first and fourth image capture devices in place of the captured images grabbed by the first to third image capture devices:
b<C≦d   (3)

b° being an angle (smaller than 90°) formed between the load face and the vertical plane in the cross section of the pipe or tube including the pipe or tube axis; and
d° being an angle (smaller than 90°) formed between a straight line and the vertical plan

Assignees

• Anayama Kazunori
• Suzuma Toshiyuki
• Nakao Yoshiyuki
• Ikeda Masami
• Sakai Kenta
• Nippon Steel & Sumitomo Metal Corp

Inventors

• Anayama Kazunori
• Suzuma Toshiyuki
• Nakao Yoshiyuki
• Ikeda Masami
• Sakai Kenta

Classifications

• G01N21/952 Primary

  Inspecting the exterior surface of cylindrical bodies or wires (G01N21/956 takes precedence) · CPC title