Wire rope flaw detector and adjustment method therefor

Patent metadata

Field	Value
Publication number	US-10724992-B2
Application number	US-201616084527-A
Country	US
Kind code	B2
Filing date	Mar 24, 2016
Priority date	Mar 24, 2016
Publication date	Jul 28, 2020
Grant date	Jul 28, 2020

Abstract

Provided is a wire rope flaw detector, which is capable of improving detection accuracy for a wire rope breakage by keeping an interval between a wire rope to be subjected to a measurement and an adjacent wire rope. The wire rope flaw detector includes: a magnetizer, which is configured to form a main magnetic path in a predetermined set interval of a wire rope in an axial direction of the wire rope; a detection coil, which is arranged in the predetermined set interval so as to be magnetically insulated from the magnetizer and is configured to detect a leakage magnetic flux generated by a damage portion of the wire rope; and position restricting mechanisms, which are configured to keep an interval between the wire rope passing through the detection coil and a wire rope adjacent to the wire rope passing through the detection coil.

First claim

The invention claimed is:

1. A wire rope flaw detector, comprising:
a magnetizer configured to form a main magnetic path in a predetermined set interval of a wire rope in an axial direction of the wire rope;
a detection coil, which is arranged in the predetermined set interval so as to be magnetically insulated from the magnetizer, and is configured to detect a leakage magnetic flux generated by a damage portion of the wire rope;
a guide plate having a guide groove through which the wire rope runs; and
position restricting mechanisms including guide rollers or U-shaped grooves configured to restrict a position of the wire rope passing through the detection coil and a position of a wire rope adjacent to the wire rope passing through the detection coil,
wherein the guide rollers or the U-shaped grooves are configured to restrict a position of the wire rope passing through the detection coil and the position of the wire rope adjacent to the wire rope passing through the detection coil to prevent the guide plate through which the wire rope runs and the wire rope from contacting each other and to prevent the guide plate and the adjacent wire rope from contacting each other.

2. The wire rope flaw detector according to claim 1 , wherein the position restricting mechanisms are arranged on both sides of the guide plate in the axial direction of the wire ropes.

3. The wire rope flaw detector according to claim 1 , wherein the position restricting mechanisms are additionally arranged on both sides of the detection coil in a direction in which the wire ropes are arranged side by side.

4. The wire rope flaw detector according to claim 1 , wherein each of the position restricting mechanisms includes a contact portion to be brought into contact with the wire rope, which is formed by a turnable roller.

5. The wire rope flaw detector according to claim 1 , wherein each of the position restricting mechanisms has a U-shaped groove through which the wire rope passes while sliding.

6. The wire rope flaw detector according to claim 1 , further comprising a force generating portion configured to press each of the position restricting mechanisms against the wire rope.

7. The wire rope flaw detector according to claim 6 , wherein the force generating portion comprises an elastic member.

8. The wire rope flaw detector according to claim 1 , wherein the guide plate has an interval to a tangent line on which the position restricting mechanism contacts with the wire rope.

9. The wire rope flaw detector according to claim 8 , wherein the guide plate has an interval to the wire rope adjacent to the wire rope passing through the detection coil.

10. The wire rope flaw detector according to claim 9 , wherein the magnetizer has a pair of permanent magnets for excitation and magnet pole pieces which are made of ferromagnetic material and arranged on magnetic pole surfaces of the permanent magnets respectively,
the detection coil is arranged between the magnet pole pieces,
the guide plate is arranged so as to held in close contact with the magnet pole pieces.

11. The wire rope flaw detector according to claim 8 , wherein the magnetizer has a pair of permanent magnets for excitation and magnet pole pieces which are made of ferromagnetic material and arranged on magnetic pole surfaces of the permanent magnets respectively,
the detection coil is arranged between the magnet pole pieces,
the guide plate is arranged so as to held in close contact with the magnet pole pieces.

12. The wire rope flaw detector according to claim 1 , wherein the guide plate has an interval to the wire rope adjacent to the wire rope passing through the detection coil.

13. The wire rope flaw detector according to claim 12 , wherein the magnetizer has a pair of permanent magnets for excitation and magnet pole pieces which are made of ferromagnetic material and arranged on magnetic pole surfaces of the permanent magnets respectively,
the detection coil is arranged between the magnet pole pieces,
the guide plate is arranged so as to held in close contact with the magnet pole pieces.

14. The wire rope flaw detector according to claim 1 , wherein the magnetizer has a pair of permanent magnets for excitation and magnet pole pieces which are made of ferromagnetic material and arranged on magnetic pole surfaces of the permanent magnets respectively,
the detection coil is arranged between the magnet pole pieces,
the guide plate is arranged so as to held in close contact with the magnet pole pieces.

15. An adjustment method for a wire rope flaw detector,
the wire rope flaw detector comprising:
a probe having a U-shaped guide groove through which a wire rope runs, the probe comprising a magnetizer, which is configured to form a main magnetic flux in a predetermined set interval of the wire rope in an axial direction of the wire rope, and a detection coil, which is arranged in the predetermined set interval so as to be magnetically insulated from the magnetizer and is configured to detect a leakage magnetic flux generated by a damage portion of the wire rope; and
position restricting mechanisms to be brought into contact with the wire rope,

the method comprising:
adjusting a relative positional relationship between the probe and the position restricting mechanisms by a jig including a guide groove contact portion to be brought into engagement with the guide groove, and guide roller contact portions to be brought into engagement with guide rollers of the position restricting mechanisms or guide block contact portions to be brought into engagement with guide blocks of the position restricting mechanisms.

Assignees

• Mitsubishi Electric Corp

Inventors

• Hirota Kazuaki
• Yoshioka Takashi
• Takahashi Fumitake
• Seki Tetsuro

Classifications

• G01N27/87

  using probes · CPC title

• G01N27/83 Primary

  by investigating stray magnetic fields · CPC title

• G01N27/82 Primary

  for investigating the presence of flaws · CPC title

• B66B7/1215

  specially adapted for ropes or cables · CPC title

• G01N2291/2626

  Wires, bars, rods · CPC title