Title:
METHOD FOR INSPECTING ROLLING PART AND DEVICE FOR INSPECTING ROLLING PART
Document Type and Number:
WIPO Patent Application WO/2019/117297
Kind Code:
A1
Abstract:
In the present invention, excitation currents are applied to an excitation coil disposed facing a rolling part, thereby generating a magnetic field, and in accordance with an eddy-current detection signal detected from a detection coil, a rolling part is inspected. The excitation currents are: a surface layer detection current of a frequency that causes an eddy current to permeate a surface layer of the rolling part; and a deep layer detection current of a frequency that causes an eddy current to permeate a deep layer that is deeper than the surface layer. A first determination step, a second determination step, and a third determination step are implemented by using a surface layer detection signal detected by the surface layer detection current and a deep layer detection signal detected by the deep layer detection current. In addition, the determination results of each step are combined to determine a surface state of the rolling part.
Inventors:
KOBAYASHI DAISUKE (JP)
Application Number:
PCT/JP2018/046153
Publication Date:
June 20, 2019
Filing Date:
December 14, 2018
Export Citation:
Assignee:
NSK LTD (JP)
International Classes:
G01N27/90
Domestic Patent References:
| WO2017022328A1 | 2017-02-09 | |||
| WO2008031387A1 | 2008-03-20 |
Foreign References:
| JP2013224916A | 2013-10-31 | |||
| JP2011106932A | 2011-06-02 | |||
| JPS5821159A | 1983-02-07 | |||
| JP2009133686A | 2009-06-18 | |||
| JPS61155754A | 1986-07-15 | |||
| US20110136408A1 | 2011-06-09 |
Attorney, Agent or Firm:
EIKOH PATENT FIRM, P.C. (JP)
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