ARRANGEMENT AND METHODS FOR CONDITION MONITORING OF THE TRACTION BELT AND/OR THE TRACTION BELT TERMINATION

Abstract

An arrangement for condition monitoring of a traction belt and/or termination of a traction belt, wherein the arrangement comprises at least two independent condition monitoring means. The invention contains independent claims also for methods for the condition monitoring of the traction belt and/or termination of the traction belt, as well as a method for evaluating the way how traction belts wear, and an elevator.

Claims

1. An arrangement for condition monitoring of a traction belt and/or a termination of a traction belt, the arrangement comprising at least two independent condition monitoring means.

2. The arrangement according to claim 1, wherein: the condition monitoring means for condition monitoring of a traction belt of an elevator comprise: at least two steel ropes inside the traction belt, which steel ropes cover the entire length between the opposite ends of the traction belt and are divided or dividable in at least two independent groups; and means for measuring the electric resistance of the steel ropes of each independent group; and wherein: the means for measuring the electric resistance of the steel ropes of each independent group are configured to detect condition or rupturing of the traction belt.

3. The arrangement according to claim 1, wherein: the steel ropes inside each independent group are connected or connectable in series to enable measuring the electric resistance at only one end of the traction belt.

4. The arrangement according to claim 1, wherein: the condition monitoring means further comprise a condition monitoring means to which at least one monitoring limit for the electric resistance of the steel ropes of each independent group is determined or determinable.

5. The arrangement according to claim 1, wherein: the limit or at least one of said limits is a warning limit.

6. The arrangement according to claim 1, wherein: limit or at least one of said limits is an alarm limit.

7. The arrangement according to claim 1, wherein: the means for the electric resistance measuring comprise a connector at the end of traction belt making groupwise an electric connection between the groups and the means for measuring the electric resistance.

8. The arrangement according to claim 1, wherein: the connector is a comb-like connector.

9. The arrangement according to claim 1, wherein: the condition monitoring means for condition monitoring of a termination of a traction belt comprise: a prime clamp; at least one supplementary clamp; a monitoring switch between the prime clamp and the supplementary clamp; and at least one traction belt forming a slack bend at the location of the monitoring switch; and wherein: the slack bend of the traction belt and the monitoring switch are mutually so positioned that a rupture of the prime clamp causes the traction belt to change a switch state of the monitoring switch.

10. The arrangement according to claim 1, wherein: the monitoring switch is connected or connectable to the means for measuring the electric resistance of the steel ropes of each independent group.

11. The arrangement according to claim 1, wherein: the supplementary clamp is duplicated or duplicable for each independent group.

12. The arrangement according to claim 1, wherein: the traction belt is a toothed belt.

13. A method for condition monitoring of a traction belt and/or a termination of a traction belt, wherein: in the method the arrangement according claim 1 is used for condition monitoring of a traction belt of an elevator and/or a termination of a traction belt.

14. An elevator comprising: a hoistway; at least one elevator unit movable in the hoistway, including at least one elevator car; lifting means comprising a lift device, one or more suspension ropes and at least one traction belt; and an arrangement for condition monitoring of a traction belt of an elevator and/or a termination of a traction belt according to claim 1.

15. The elevator according to claim 1, wherein: the elevator comprises only one traction belt.

16. A method for evaluating the way how traction belts wear, wherein: the electric resistance values of each independent group of at least two traction belts are compared to find out the way how the traction belts wear.

17. A method for condition monitoring of a traction belt and/or a termination of traction belt, wherein: the traction belt and/or termination of traction belt is divided in portions, each portion being capable to carry at least the intended load of the traction belt; at least one criterion for each of the portions of the traction belt and/or the termination of traction belt is set to judge a failure; and if one or more of the at least one criterion is met then a failure in capacity to carry the load is indicated.

18. The method according to claim 17, wherein: the traction belt is divided in portions by dividing steel ropes of the traction belt at least two independent groups; measuring the electric resistance of the steel ropes of each independent group; and detecting condition or rupturing of the traction belt by the means for measuring the electric resistance of the steel ropes of each independent group.

19. The method according to claim 17, wherein: the termination is divided in portions by installing: a prime clamp; at least one supplementary clamp; a monitoring switch between the prime clamp and the supplementary clamp; at least one traction belt forming a slack bend at the location of the monitoring switch; and by positioning mutually the slack bend of the traction belt and the monitoring switch so that a rupture of the prime clamp causes the traction belt to change a switch state of the monitoring switch.

20. The method according to claim 17, wherein: the termination is divided in portions by duplicating a supplementary clamp for each independent group.

21. The method according to claim 17, wherein: the load is intended in elevator control.

22. The method according to claim 17, wherein: the criterion is set in elevator control.

Description

LIST OF DRAWINGS

[0032] The arrangement is explained in more detail in the following by way of the exemplary embodiments shown in the attached drawings in FIG. 1 to 5.

[0033] In the drawings:

[0034] FIG. 1 is a schematic drawing of an arrangement of the condition monitoring means for condition monitoring of a traction belt wherein the ropes of the traction belt are divided in two independent monitoring groups;

[0035] FIG. 2 is a perspective view of a traction belt with comb-like connectors and wherein the ropes of the traction belt are divided to two independent monitoring groups;

[0036] FIG. 3 is a perspective view of the end of a traction belt with two clamps and a control switch and wherein the ropes of the traction belt are divided in two independent monitoring groups;

[0037] FIG. 4 is a perspective view from the left side of a traction belt with two belt clamps and a control switch and wherein the ropes of the traction belt are divided to two independent monitoring groups;

[0038] FIG. 5 is a perspective view of the embodiment of the traction belt with two belt clamps and a control switch and wherein supplementary clamp is doubled to two supplementary clamps;

[0039] Similar parts are marked with identical reference numbers in all FIG.

DETAILED DESCRIPTION

[0040] A conventional way to carry out redundancy in monitoring suitable condition of traction belts of an elevator is to equip the elevator with at least two parallel belts and monitor them separately. For carrying the loads, taking account to required safety factors it is technically possible to equip elevator with only one traction belt, particularly if 2:1 or higher suspension ratios are used.

[0041] An arrangement 20 for condition monitoring of a traction belt 1 of an elevator and/or a termination of a traction belt 1 comprises at least two independent condition monitoring means 13, 14. The condition monitoring means 13 are for condition monitoring of a rupturing of the traction belt 1 of an elevator and condition monitoring means 14 are for condition monitoring of a failure of the traction belt 1. The condition monitoring means 13 can be doubled as well as the condition monitoring means 14. It is possible to use condition monitoring means 13 and 14 separately or combined arbitrarily.

[0042] FIG. 1 shows a schematic drawing of the arrangement 20 of the condition monitoring means for condition monitoring of the traction belt of an elevator. The condition monitoring means 13 preferably comprise at least two steel ropes 2,2 inside the traction belt 1, which steel ropes 2, 2 are divided or dividable in at least two independent groups G1, G2 and a means 3 for measuring the electric resistance of the steel ropes 2, 2 of each independent group G1, G2. The means 3 for measuring the electric resistance of steel ropes 2, 2 of each independent group G1, G2 are configured to detect condition or rupturing of the traction belt 1.

[0043] The steel ropes 2, 2 inside each independent group G1, G2 are preferably connected or connectable in series to enable measuring the electric resistance only at one end A, B of the traction belt 1. Electric cables 12 connecting the steel ropes 2, 2 to the means 3 for measuring the electric resistance. The electric cables 12 are therefore preferably only in one end A, B of the traction belt 1. The condition of a traction belt 1 of an elevator can be monitored over the entire length of the traction belt 1, since the steel ropes 2, 2 cover the entire length between the opposite ends A, B of the traction belt 1.

[0044] The condition monitoring means 13 further comprise a condition monitoring means 22 to which at least one monitoring limit 4 for the electric resistance of the steel ropes 2, 2 of each independent group G1, G2 is determined or determinable. The electric resistance of a steel rope 2, 2 changes when the steel rope 2, 2 wears out, rupturing or if any cord of the steel rope 2, 2 breaks off. It is possible to measure and detect the changes of the electric resistance and determine the monitoring limits for warning and alarm and proceed specified actions according the set limits. The electric resistance can either increase or decrease because of the rupture of the traction belt. A 10% change in electric resistance referring to the initial value (traction belt is new and installed) may be defined as the warning limit and a 20% change as the alarm limit. When comparing the traction belts 1 and electric resistance values of each independent group G1, G2, it is possible to find out the way how the traction belts 1 wear.

[0045] FIG. 2 shows a perspective view of the arrangement wherein the means 3 for measuring of the electric resistance comprise a connector 7 at the end of the traction belt A, B making group-wise an electric connection between the groups G1, G2 and the means 3 for measuring the electric resistance. The connector 7 is preferably a comb-like connector. The needles of the comb-like connector 7 may contact with the steel ropes 2, 2 inside the traction belt 1. It is obvious that the steel ropes 2, 2 of the traction belt also can be peeled in the area of the connector 7 before connecting the connector 7 to the steel ropes 2, 2. A heating of the traction belt 1 can be utilized to softening the polymer of the traction belt 1 when making an electric connection between the steel ropes 2, 2 and the connector 7.

[0046] FIGS. 3 and 4 show the arrangement wherein the condition monitoring means 14 for condition monitoring of a termination of the traction belt 1 comprise a prime clamp 8, at least one supplementary clamp 9, a monitoring switch 10 between the prime clamp 8 and the supplementary clamp 9 and at least one traction belt 1 forming a slack bend 11 at the location of the monitoring switch 10. The slack bend 11 of the traction belt 1 and the monitoring switch 10 are mutually so positioned that a rupture of the prime clamp 8 causes the traction belt 1 to change a switch state of the monitoring switch 10. The monitoring switch 10 can be switch-off or alarming type.

[0047] The prime clamp 8 is before the supplementary clamp 9 seen from the direction of the traction 16, 17.

[0048] The condition monitoring means 14 for condition monitoring of a termination of the traction belt 1 can be mounted to the one end A, B of the traction belt 1 or to the both ends of the traction belt A, B.

[0049] FIG. 4 shows a situation when a rupture of the prime clamp 8 causes the traction belt 1 to change a switch state of the monitoring switch 10. The traction belt 1 after straighten the slack bend is illustrated with dashed lines.

[0050] One end A, B of the traction belt 1 is fixed by clamps 8,9 to the elevator car. The other end A, B of the traction belt 1 is preferably fixed to the counterweight or to compensating weights via a machine station. One end A, B of the traction belt 1 can be fixed also to a fixed structure of the hoistway. The traction belt 1 is preferably a toothed belt.

[0051] The monitoring switch 10 is preferably connected or connectable to the means 3 for measuring the electric resistance of the steel ropes 2, 2 of each independent group G1, G2. This kind of connection can reduce the number of electric cables especially when the traction belt 1 is connected to the counterweight or to compensating weights.

[0052] The rupture of a termination of the prime clamp 8 and transfer of the load from the prime clamp 8 to the supplementary clamp 9 can also be detected by making the connector 7 in such a way that the connector 7 can breaks away when the load transfer to the supplementary clamp 9.

[0053] In one embodiment of the present invention the supplementary clamp 9 may be duplicated or duplicable to each independent group G1, G2.

[0054] In a method for condition monitoring of the traction belt 1 of an elevator or/and a termination of a traction belt 1 the arrangement 20 for condition monitoring of the traction belt 1 of an elevator or/and a termination of a traction belt 1 according to the first aspect of the present invention is used for condition monitoring of the traction belt 1 of an elevator or/and a termination of a traction belt 1.

[0055] An elevator comprises a hoistway, at least one elevator unit movable in the hoistway, including at least one elevator car, lifting means comprising a lift device, one or more suspension ropes and at least one traction belt 1 and an arrangement for condition monitoring of a traction belt 1 of an elevator and/or a termination of a traction belt 1 according to the first aspect of the present invention. In one embodiment the elevator comprises only one traction belt 1.

[0056] In the method for evaluating the way how traction belts 1 wear, the electric resistance values of each independent group G1, G2 of at least two traction belts 1 are compared to find out the way how the traction belts 1 wear. When collecting and comparing electric resistance values of different traction belts and collecting this data the data from the wearing of the traction belts in different environments and load conditions can be collected. Maintenance needs can be anticipated according to this collected data.

[0057] In the method for condition monitoring of a traction belt and/or a termination of traction belt the traction belt/the termination is divided in portions, which each portion capable to carry at least the intended load of the traction belt, a criterion for each of the portions of the traction belt and/or the termination of traction belt is set to judge a failure, if one or more such a criterion is met then a failure in capacity to carry the load is indicated.

[0058] In the method for condition monitoring of a traction belt and/or a termination of traction belt the traction belt is divided in portions by dividing the steel ropes 2, 2 at least two independent groups G1, G2, measuring the electric resistance of the steel ropes 2, 2 of each independent group G1, G2 and detecting condition or rupturing of the traction belt 1 by the means 3 for measuring the electric resistance of the steel ropes 2, 2 of each independent group G1, G2.

[0059] In the method for condition monitoring of a traction belt and/or a termination of traction belt the termination is divided in portions by installing a prime clamp 8, at least one supplementary clamp 9, a monitoring switch 10 between the prime clamp 8 and the supplementary clamp 9 and at least one traction belt 1 forming a slack bend 11 at the location of the monitoring switch 10. The slack bend 11 of the traction belt 1 and the monitoring switch 10 are positioned mutually so that a rupture of the prime clamp 8 causes the traction belt 1 to change a switch state of the monitoring switch 10.

[0060] In the method for condition monitoring of a traction belt and/or a termination of traction belt the termination is divided in portions by doubling the supplementary clamp 9 for each independent group G1, G2.

[0061] In the method for condition monitoring of a traction belt and/or a termination of traction belt the load is intended in elevator control (EC).

[0062] In the method for condition monitoring of a traction belt and/or a termination of traction belt the criterion is set in elevator control (EC).

[0063] It is obvious to the skilled person that, along with the technical progress, the basic idea of the invention can be implemented in many ways. The invention and its embodiments are thus not limited to the examples described above but they may vary within the contents of patent claims and their legal equivalents.

LIST OF REFERENCE NUMERALS USED

[0064] EC elevator control [0065] A end of traction belt [0066] B end of traction belt [0067] 1 traction belt [0068] 2 steel rope [0069] 2 steel rope [0070] 3 means for measuring an electric resistance [0071] 4 monitoring limit [0072] 5 warning limit [0073] 6 alert limit [0074] 7 connector [0075] 8 prime clamp [0076] 9 supplementary clamp [0077] 10 monitoring switch [0078] 11 slack bend [0079] 12 electric cable [0080] 13 condition monitoring means [0081] 14 condition monitoring means [0082] 16 direction of traction [0083] 17 direction of traction [0084] 20 arrangement [0085] 21 microcontroller [0086] 22 condition monitoring means [0087] 23 comparing unit