US 12,085,519 B2
Loosening detection structure and loosening detection method using said structure
Eri Matsunaga, Musashino (JP); Tadashi Minotani, Musashino (JP); Masahito Nakamura, Musashino (JP); Masayuki Tsuda, Musashino (JP); and Takashi Sawada, Musashino (JP)
Assigned to Nippon Telegraph and Telephone Corporation, Tokyo (JP)
Appl. No. 17/614,660
Filed by Nippon Telegraph and Telephone Corporation, Tokyo (JP)
PCT Filed May 30, 2019, PCT No. PCT/JP2019/021473
§ 371(c)(1), (2) Date Nov. 29, 2021,
PCT Pub. No. WO2020/240765, PCT Pub. Date Dec. 3, 2020.
Prior Publication US 2022/0228996 A1, Jul. 21, 2022
Int. Cl. G01N 22/02 (2006.01); G01N 27/22 (2006.01)
CPC G01N 22/02 (2013.01) [G01N 27/226 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A looseness detection structure comprising:
a structure which is formed on a surface of a cable;
at least one screw configured to tighten and fix the cable in contact with the structure; and
a detection unit configured to transmit a transmission signal to the structure, receive a reception signal returning after propagating through the structure, and detect loosening of the screw based on a change in the reception signal,
wherein the structure is a three-laver structure in which a first conductive sheet, an insulating sheet, and a second conductive sheet are laminated on the surface of the cable in that order, and
wherein the detection unit allows electromagnetic waves to reach the first conductive sheet and the second conductive sheet and detects the loosening of the screw based on a change in resonance frequency of the electromagnetic waves.