Method and hoisting device

Patent metadata

Field	Value
Publication number	US-10968078-B2
Application number	US-201815889571-A
Country	US
Kind code	B2
Filing date	Feb 6, 2018
Priority date	Feb 14, 2017
Publication date	Apr 6, 2021
Grant date	Apr 6, 2021

Abstract

The invention relates to a method for monitoring condition of a rope of a hoisting device, which rope comprises one or more load bearing members oriented to extend parallel with longitudinal direction of the rope throughout the length thereof. The method comprises measuring strains of one or more portions of a load bearing member of the rope; and comparing the measured strains of one or more portions of a load bearing member of the rope with at least one reference. The invention also relates to a hoisting device implementing the method.

First claim

The invention claimed is:

1. A method of monitoring a condition of a rope of a hoisting device, the rope including one or more load bearing members oriented to extend parallel with a longitudinal direction of the rope throughout a length thereof, the method comprising:
reading, via a receiver located adjacent to a rope wheel of the hoisting device, measurements of strains of one or more portions of a load bearing member of the rope as the one or more portions of the one or more load bearing members rests on a circumference of the rope wheel such that the measurements are associated with the strains observed when the one or more portions are arched by the rope wheel; and
comparing the measured strains of the one or more portions of the load bearing member of the rope with at least one reference.

2. The method according to claim 1 , wherein a measuring point is where the one or more portions substantially arcs, with diameter less than 1.5 meters.

3. The method according to claim 1 , wherein each said load bearing member is made of composite material including reinforcing carbon fibers or glass fibers embedded in polymer matrix.

4. The method according to claim 1 , wherein the rope is substantially larger in its width-direction than thickness-direction.

5. The method according to claim 1 , wherein said measuring is performed by aid of one or more strain gauges.

6. The method according to claim 1 , wherein the rope includes one or more strain gauges fixed on each of said one or more portions of the load bearing member for measuring strain of the portion with one or more strain gauges.

7. The method according to claim 5 , wherein the rope includes a coating forming an outer surface of the rope, with the one or more load bearing members embedded in the coating.

8. The method according to claim 7 , wherein each said strain gauge is covered by the coating.

9. The method according to claim 1 , wherein the method comprises:
measuring strains of a plurality of portions of the one or more load bearing members of the rope; and
comparing each measured strain with at least one reference, wherein said plurality of portions are portions of the one or more load bearing members of the rope successive in longitudinal direction of the load bearing member of the rope.

10. The method according to claim 1 , wherein said at least one reference includes one of (i) a reference input by a person to a monitoring system of the hoisting device performing said method or (ii) a reference determined automatically by the monitoring system of the hoisting device performing said method.

11. The method according to claim 1 , wherein said at least one reference includes one of (i) a reference which is a strain measured from the same portion of the load bearing earlier, or a strain measured from some other portion of the load bearing, or (ii) a strain which is an average strain calculated from plurality of measured strains of one or more portions of the load bearing, or (iii) a measured strain of a portion of another, parallel, load bearing member extending parallel with the load bearing member under inspection, said portion of another parallel load bearing member preferably being beside the portion in question.

12. The method according to claim 1 , wherein the method comprises:
performing one or more predefined actions if the comparing the measured strains with the at least one reference fulfills one or more criteria.

13. The method according to claim 1 , wherein said measuring is performed using one or more strain gauges fixed on either (i) a face of the load bearing member which face faces in width direction of the rope or (ii) a face of the load bearing member which face faces in thickness direction of the rope.

14. The method according to claim 1 , wherein said measuring is performed using one or more strain gauges having a measuring direction parallel with the longitudinal direction of the load bearing member on which it is fixed or using one or more strain gauges having a measuring direction at an angle relative to the longitudinal direction of the load bearing member on which it is fixed.

15. The method according to claim 1 , wherein the method comprises:
transmitting measurement data from one or more strain gauges to an external receiver with a wireless communication unit installed within the rope.

16. The method according to claim 15 , wherein the wireless communication unit is an RFID unit.

17. The method according to claim 1 , wherein said rope is a rope installed in the hoisting device.

18. A hoisting device, comprising:
a rope including one or more load bearing members oriented to extend parallel with longitudinal direction of the rope throughout a length thereof;
a rope wheel with a receiver adjacent thereto; and
a controller configured to,
read, via the receiver, measurements of strains of one or more portions of the one or more load bearing members of the rope as the one or more portions of the one or more load bearing members rests on a circumference of the rope wheel such that the measurements are associated with the strains observed when the one or more portions are arched by the rope wheel; and
compare the measured strains of the one or more portions of the one or more load bearing members of the rope with at least one reference.

19. The hoisting device according to claim 18 , wherein the receiver is located adjacent to the rope wheel such that the controller reads the measurements of the strains at a measuring point where the one or more portions substantially arcs, with diameter less than 1.5 meters.

20. The hoisting device according to claim 18 , wherein said at least one reference includes one of (i) a reference which is a strain measured from the same portion of the load bearing earlier, or a strain measured from some other portion of the load bearing, or (ii) a strain which is an average strain calculated from plurality of measured strains of one or more portions of the load bearing, or (iii) a measured strain of a portion of another, parallel, load bearing member extending parallel with the load bearing member under inspection, said portion of another parallel load bearing member preferably being beside the portion in question.

Assignees

• Kone Corp

Inventors

• Lehtinen Hannu
• Penttila Jukka
• Helenius Juha

Classifications

• B66B7/1223

  by analysing electric variables · CPC title

• G01L1/22

  using resistance strain gauges · CPC title

• D07B1/145

  comprising elements for indicating or detecting the rope or cable status · CPC title

• B66B5/0031 Primary

  for safety reasons · CPC title

• G01L1/225

  Measuring circuits therefor · CPC title