Method and device for checking the integrity of load bearing members of an elevator system

Patent metadata

Field	Value
Publication number	US-2016229667-A1
Application number	US-201615099997-A
Country	US
Kind code	A1
Filing date	Apr 15, 2016
Priority date	Oct 22, 2013
Publication date	Aug 11, 2016
Grant date	—

Abstract

A method for checking the integrity of a load bearing member of an elevator comprising tensile elements encapsulated in a case is disclosed; the method comprises the steps of launching a source pulse through tensile elements of said load bearing member and comparing the feedback of said tensile elements with a comparator; tensile elements can be bridged to avoid a blind zone; an elevator system with a checking device to perform said method is also disclosed.

First claim

1 . A method for checking at least one load bearing member of an elevator system, said load bearing member comprising tensile elements of electrically conductive material encapsulated in a case, the method comprising the steps of:
a) launching a first source pulse through a first tensile element of said load bearing member, b) launching a second source pulse through a second tensile element of said load bearing member or of another load bearing member of said elevator system, c) making a comparison between a feedback received from said first tensile element and a feedback received from said second tensile element, and d) determining a condition of said tensile elements based on said comparison.

2 . A method according to claim 1 , including the step of determining a damage condition of one of said first tensile element and second tensile element when said comparison reveals a difference between the feedback of the tensile elements greater than a predetermined threshold.

3 . A method according to claim 2 , comprising the step of: when a damage condition is determined, at least one of said first tensile element and second tensile element is compared at least to a third tensile element of said load-bearing member or of another load-bearing member of the elevator system, according to steps a) to d).

4 . A method according to claim 1 , wherein: the tensile elements of a load-bearing member are tested by testing pairs of tensile elements according to steps a) to d), and wherein the pairs are selected in such a way that each tensile element of said load bearing member are compared to a plurality of other tensile elements of the same or other load bearing member(s) according to a predetermined pattern or according to a random pattern.

5 . A method according to claim 1 , wherein the step c) includes any of: a measure of the time elapsed between the launch of the source pulse and the receipt of any feedback pulse; determination of amplitude of any feedback pulse, determination of the duration of any feedback pulse;
analysis of the waveform of any feedback pulse, or a combination thereof.

6 . A method according to claim 1 , wherein tensile elements of said load-bearing member are bridged in pairs, the method including the steps of:
launching a first source pulse into a first tensile element of a first bridged pair and launching a second source pulse into a first tensile element of a second bridged pair, and making a comparison of the received feedback, and repeating the test by launching a first source pulse into the second tensile element of said first bridged pair and launching a second source pulse into the second tensile element of said second bridged pair, and making a comparison of the received feedback.

7 . A method according to claim 1 , the first source pulse and the second source pulse being identical.

8 . A method according to claim 1 , wherein the first source pulse and the second source pulse are launched simultaneously.

9 . A method according to claim 1 , wherein said source pulse has a time duration of 100 nanoseconds or less.

10 . A method according to claim 1 , wherein said source pulse has an amplitude not greater than 50 V.

11 . An elevator system including at least one car and at least one load-bearing member, the load bearing member including tensile elements made of electrically conductive material and encapsulated in a case, the elevator comprising a checking device for checking the integrity of said load-bearing member according to the method of claim 1 , said device comprising at least: a pulse generator connected to tensile elements of said load-bearing member and possibly to tensile elements of other load-bearing members of said elevator system, and a comparator which is also connected to said tensile elements and is arranged to compare the feedback of tensile elements, and to analyse said feedback in order to determine a condition of said tensile elements.

12 . An elevator system according to claim 11 , said checking device being configured to perform a test of the integrity of the tensile elements at predetermined intervals of time.

13 . An elevator system according claim 11 , said control system being configured to perform a test of the integrity of the tensile elements when a call of the elevator is made while the car is positioned at the lowest floor.

14 . An elevator system according to claim 11 , said load-bearing member being formed as a belt and the elevator having no counterweight.

15 . An elevator system including at least one car and at least one load-bearing member, the load bearing member including tensile elements made of electrically conductive material and encapsulated in a case made of electrically resistive material, the elevator comprising a checking device for checking the integrity of said load-bearing member, said device comprising at least: a pulse generator connected to tensile elements of said load-bearing member and a comparator or analyzer which is also connected to said tensile elements and is arranged to compare or analyze the feedback of tensile elements, and criteria for determine whether the condition of said tensile element is acceptable or not.

Assignees

• Cereghetti Igino
• Pellascio Simone
• Kone Corp

Inventors

• Cereghetti Igino
• Pellascio Simone

Classifications

• B66B7/1223 Primary

  by analysing electric variables · CPC title