Method and device for detecting damage in a support for an elevator system

Abstract

A method and a correspondingly configured device detect damage or defects in a support, including at least one tension member, for an elevator system. A pulse generator generates at least one electrical digital input signal that represents at least one first binary number and is fed to the tension member. After the digital input signal has passed through the tension member, it is detected as a digital output signal that likewise represents at least one second binary number. The second binary number is then compared, in particular compared digit by digit or bit by bit, with a setpoint binary number and/or directly with the first binary number. Damage in the tension member is determined on the basis of an issued comparison result. If the second binary number deviates from the setpoint binary number and/or from the first binary number, a fault message is generated.

Claims

1. A method for detecting damage in an elevator system support means having at least one tension member, the method comprising the steps of: generating a digital input signal from a pulse generator, wherein the digital input signal represents a first binary number; feeding the digital input signal to the at least one tension member of the support means; detecting a digital output signal after the digital input signal has passed through the at least one tension member, wherein the digital output signal represents a second binary number; comparing the second binary number with at least one of a setpoint binary number and the first binary number; reporting a fault state of the support means when the second binary number differs from the setpoint binary number or the first binary number; and wherein the setpoint binary number has a predetermined constant value or is generated dynamically based upon a current value of the digital input signal.

2. A method for detecting damage in an elevator system support means having at least one tension member, the method comprising the steps of: generating a digital input signal from a pulse generator, wherein the digital input signal represents a first binary number; feeding the digital input signal to the at least one tension member of the support means; detecting a digital output signal after the digital input signal has passed through the at least one tension member, wherein the digital output signal represents a second binary number; comparing the second binary number with at least one of a setpoint binary number and the first binary number; reporting a fault state of the support means when the second binary number differs from the setpoint binary number or the first binary number; and wherein the support means has a plurality of tension members including the at least one tension member, wherein the tension members are grouped into at least one group, and wherein when the tension members are grouped into at least two groups, the at least one group includes an identical number or a different number of the tension members as another of the groups.

3. The method according to claim 2 wherein the steps are performed individually for each of the tension members, or are performed simultaneously for all of the tension members in each of the groups individually, or are performed simultaneously for all of the tension members in all of the groups, and wherein the first binary number is different for at least two of the tension members.

4. The method according to claim 3 including generating the digital input signal with a number of digits of the first binary number being identical to or larger than a number of the tension members of the support means or a number of the tension members in a group of the tension members.

5. The method according to claim 4 wherein the first binary number has a first extra digit, and wherein a position of the first extra digit in the first binary number represents an associated one of the tension members of the support means or an associated one of the tension members in the group of the tension members.

6. The method according to claim 5 wherein the positions of the first extra digits of the first binary numbers within the group or within the support means are different from each other.

7. The method according to claim 6 wherein the positions of the first extra digits of the first binary numbers are shifted relative to each other and correspond to a sequence of the tension members in the group or a sequence of the tension members in the support means.

8. The method according to claim 2 including adding the second binary numbers associated with at least two of the tension members to obtain a resulting sum, evaluating the resulting to determine damage in the at least two tension members by comparing the resulting sum with at least one of the setpoint binary number and the first binary numbers associated with the at least two tension members.

9. The method according to claim 8 including defining the resulting sum as a special value when at least two of the first binary numbers and the second binary numbers have a different period duration or different numbers of digits.

10. The method according to claim 2 wherein the first binary number has at least one second extra digit that represents a predetermined group of the tension members, and wherein a binary value of the second extra digit is the same for all of the tension members in the predetermined group.

11. A method for detecting damage in an elevator system support means having at least one tension member, the method comprising the steps of: generating a digital input signal from a pulse generator, wherein the digital input signal represents a first binary number; feeding the digital input signal to the at least one tension member of the support means; detecting a digital output signal after the digital input signal has passed through the at least one tension member, wherein the digital output signal represents a second binary number; comparing the second binary number with at least one of a setpoint binary number and the first binary number; reporting a fault state of the support means when the second binary number differs from the setpoint binary number or the first binary number; and performing the steps in an event-controlled manner, by at least one of manually and automatically, when an elevator system that includes the support means is out of service, in a maintenance or installation state, or in a waiting period.

12. A device for detecting damage in an elevator system support means including at least one tension member, the device comprising: a pulse generator for generating a digital input signal representing a first binary number and applying the digital input signal to a first connection of the at least one tension member; a detector for detecting a digital output signal at a second connection of the at least one tension member, wherein the output signal represents a second binary number; a processor for comparing the second binary number with at least one of a setpoint binary number and the first binary number; a fault indicator for generating a fault message when the second binary number differs from the setpoint binary number or the first binary number; and wherein the pulse generator is connected with a signal source that generates an electrical analog signal to the pulse generator.

13. The device according to claim 12 wherein the setpoint binary number has a specified constant value or is generated dynamically based upon a current value of the digital input signal by the processor.

14. The device according to claim 12 wherein the pulse generator and the detector operate with an identical frequency and period duration.

15. The device according to claim 12 being activated in an event-controlled manner, by at least one of manually and automatically, when an elevator system including the support means is out of service, in a maintenance or installation state, or in a waiting period.

Description

DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a schematic illustration of a device according to the invention for detecting damage in a support means for an elevator system,

(2) FIG. 2 shows an exemplary embodiment for a determination of damage in an individual tension member of the support means.

DETAILED DESCRIPTION

(3) FIG. 1 shows a device 1 according to the invention for detecting damage in a support means 2 for an elevator system (not illustrated). The support means 2 can for example be a belt, a rope or the like. Today, belts are frequently used as modern support means for elevator systems. The support means 2 has at least one tension member (not illustrated in FIG. 1), wherein the tension member can consist of an electrically conductive material, such as, e.g., steel.

(4) An analog electrical signal 6 is generated by means of a signal source, such as, e.g., a direct voltage or direct current source 16. A pulse generator 9 subsequently provides for a conversion of analog signals into digital signals. The analog electrical signal 6, e.g. a matching current or an adequate voltage, is hereby converted into a digital electrical input signal 4 or in the form of a first binary number 4B, respectively.

(5) In a simplest way, the pulse generator 9 can be an A/D converter or can generate a settable basic clock for pulse sequences, respectively, i.e. settable pulse group subsequent periods. The pulse generator 9 may be configured as a pulse width modulator (PWM), so that the input signal 4 can also be generated in the form of pulse sequence and the pulse amplitude or signal level or the pulse width, respectively, can be flexibly adjusted as needed. One advantage for this is that the bit time for a logical one “1” and a logical zero “0” can be placed differently as needed.

(6) The pulse sequence generated by the pulse generator 9, thus the digital input signal 4, can be fed flexibly on an individual support member 3 of the support means 2 either separately or on several or all of the tension members 3 of the support means 2, in part or simultaneously to all with the help of a software or an electronic circuit technology, such as, e.g. a multiplexer, TTL (transistor-transistor-logic) or CMOS (complementary metal-oxide-semiconductor), respectively. Such a multiplexer can also be made so as to be integrated into the pulse generator 9.

(7) The digital input signal 4 can be assigned to a tension member 31 (FIG. 2) and can be applied to the first connection 3A thereof. The digital input signal 4 or the first binary number 4B, respectively, is thereby fed to the tension member 31 and is transferred by means of this tension member 31 to the second connection 3B thereof. The second connection 3B is located at the opposite end of the tension member 3 opposite to the first connection 3A. The connections 3A and 3B thereby serve as an interface, which is able to transmit the binary numbers fed to the support means 2 either individually or together or in combination.

(8) A digital output signal 5 can be detected by a detector 10 on the second connection 3B, wherein the output signal 5 is likewise represented by means of at least one second binary number 5B. The digital output signal is in fact considered to be a first input signal, which is transmitted from the first connection by means of the tension member to the second connection. The device 1 further has a processor 11, which can receive digital signals from the detector 10, and a fault indicator 12 for generating a fault message. The signal processor 11 can receive and analyze the output signals 5 continuously or at regular time intervals from the detector 10. A synchronization 19 exists between the detector 10 and the pulse generator 9, so that the two units can work at the same clock rate in response to signal processing. The clock is determined by the frequency or the period duration of the generated input signal 4.

(9) The second binary number 5B detected by the detector 10 can either be compared with a binary setpoint binary number 14 or directly bit by bit with the corresponding first binary number 4B by means of the processor 11. The binary setpoint binary number 14 can be stored beforehand as a reference value or can be generated dynamically by the processor 11 on the basis of the current first binary number 4B. A comparison result resulting therefrom is analyzed or evaluated, respectively, in the processor 11. When the second binary number 5B is not identical to the first binary number 4B and/or to the setpoint binary number 14, a fault message is generated. The fault message can be generated in different forms, such as, e.g. acoustically or optically. The fault message will be transmitted to a control device of the elevator system or to a monitoring center and/or maintenance center 13, respectively, located at a distance from the elevator system, in order to point out a risk of damage present in the tension member 31 or in the support means 2, respectively.

(10) Even though it is shown in FIG. 1 that the device 1 and the signal source 16 are located within the elevator system, it is not ruled out, however, that this device 1 or the signal source 16, respectively, are arranged outside or at least partially outside of the elevator system.

(11) FIG. 2 shows an exemplary embodiment for a determination of damage in an individual tension member 3 of the support means 2. A detection method can be carried out either separately for one tension member 3 or simultaneously for several tension members 3. In this exemplary embodiment, the support means 2 is provided with a total of twelve tension members 3. The twelve tension members 3 are thus distributed into three groups 7a, 7b, 7c, so as to be able to more quickly determine or detect damage in the support means 2. The respective groups 7a, 7b, 7c comprise four tension members, wherein the first group 7a has the tension members 31, 32, 33 and 34. That is, the number of all of the tension members 3 of the support means 2 is a triple number of the number of the tension members 3 in a group 7a, 7b, 7c. For a belt 2 with 16, 20 or 24 tension members 3, the tension members 3 can be divided, e.g. analogously to the above-described design, into four, five or six groups 7, wherein each group 7 comprises four tension members 3. For a simplified overview, only the first and the last tension member in the groups 7b and 7c are illustrated here.

(12) The detection method is carried out at the same time, e.g. for the tension members 31, 32, 33, 34 in the first group 7a. By means of the pulse generator 9, an electrical analog signal 6, which is generated by the signal source 16, can be converted into an electrical digital input signal 4 and then be generated in the form of a first binary number 4B with an identical period duration in such a way that the number of digits or the number of bits of the first binary number 4B is identical to the tension member number of the first group 7a, 7b, 7c. The generated first binary numbers 4B are then four-digit binary numbers. One of the first binary numbers 4B is assigned to each tension member 31, 32, 33, 34, whereby the tension members 31, 32, 33, 34 are analyzed by means of the digital input signal 4 or the first binary number 4B, respectively.

(13) The first binary number 4B has a first extra digit 4C, which is marked with a leader character “ ”. Within the group 7a, such first extra digits 4C are positioned differently to each other and are in particular shifted relative to each other. For this exemplary embodiment, each first binary number 4B has a pulse, namely a digit “1” at the extra digit 4C thereof, wherein the binary digit position of the digit “1” in the first binary number 4B represents a certain tension member 31, 32, 33, 34. In addition, the positions of the digit “1” are a sequence, which corresponds to a sequence of the tension members 31, 32, 33, 34 in the group 7a. The binary numbers 4B for the group 7a could thus be generated, e.g., in a sequence of “1000”, “0100”, “0010”, and “0001”, wherein the positions of the digit “1” signifies the four tension members 31, 32, 33, 34 of this group 7a from top to bottom.

(14) The four first binary number 4B, “1000”, “0100”, “0010”, and “0001” are fed to the respective assigned tension member 31, 32, 33, 34. An electrical digital output signal 5, which is likewise represented by a second binary number 5B, is detected at a second connection 3B of the tension member 3. The total of four second binary numbers 5B are added up, resulting in a binary number as the sum 17. This sum 17 is compared digit by digit with a binary setpoint binary number 14 or directly with the first binary numbers 4B by means of a processor 11, wherein the setpoint binary number 14 is specified as constant value or is generated dynamically by means of the processor 11 on the basis of a current digital input signal 4.

(15) Damage in the tension members 31, 32, 33, 34 can be determined on the basis of a comparison result. In the case of a good state of the support means 2, the first binary numbers “1000”, “0100”, “0010”, and “0001” are transmitted by the tension members 31, 32, 33, 34 without losses or interfering noise, respectively. I.e., the same binary numbers as the first binary numbers “1000”, “0100”, “0010”, and “0001” are to be detected at the second connection 3B. The four binary numbers are added up. A binary number of “1111” results as a sum 17. A binary number “1111” is hereby already specified as the setpoint binary number 14. It is thus known that all four tension members 31, 32, 33, 34 have no damage, when the sum 17 corresponds with the setpoint binary number 14. If damage or a wear is present in the tension members 31, 32, 33, 34, the second binary number 5B will have a binary number other than “1111”.

(16) The sum 17 can also be compared with the respective first binary numbers 4B. Damage in the tension members 31, 32, 33, 34 can be determined on the basis of an issued comparison result, if the second binary numbers 5B differ from the corresponding first binary numbers 4B. It can furthermore be determined immediately, how many and which tension member or members have damage. When, e.g. a second binary number “1011” is detected, this means that the second tension member 32 has damage. Analogously, “0111” applies for the tension member 31, “1101” for the tension member 33, and “1110” for the tension member 34.

(17) If a first binary number 4B was transmitted with a delay, the period durations or the number of digits, respectively, of the first 4B or of the second binary numbers 5B, respectively, then no longer remain identical. The second binary numbers 5B can thus not add up correctly, because the binary digit positions of the digit “1” in the second binary numbers 5B are not shifted exactly digit by digit. A third value “X” is placed next to the digit “0” and “1” in this case, which suggests an unknown state. The sum 17 is then set as a third value “X”.

(18) When damage or an unknown state was detected in one of the tension members 31, 32, 33, 34, a fault message is generated by a fault indicator 12. This fault message can be transmitted to a monitoring center and/or maintenance center 13.

(19) This transmission can take place, e.g. by means of a public or private network 18, such as Internet or LAN (local area network) and by means of wired or wireless transmissions. The connection of the device 1 or of the elevator system, respectively, to the center 13 can thereby take place via mobile communications, DSL (digital subscriber line) or existing private network infrastructures.

(20) Furthermore, the first binary number 4B can additionally have a second extra digit 4D, which can represent or show a certain group 7, wherein a binary value at the second extra digit remains unchanged. The second extra digit 4D can also be generated separately from the first binary number 4B by the pulse generator 9, i.e. the first binary number 4B and the second extra digit 4D can either be represented together by a binary number or separately by two binary numbers. A binary number of the individual group 7a, 7b, 7c can thus also be differentiated from each other. One example for this would be that the binary numbers 100001, 010001 represent the first 31 and the second tension member 32 of the first group 7a, the binary numbers 010010, 001010 represent the second 32 and the third tension member 33 of the second group 7b, and the binary numbers 001011, 000111 represent the third 33 and the fourth tension member 34 of the third group 7c, wherein the last two binary digits, which are marked with underlining, are the second extra digits 4D.

(21) Such a detection nor determination method, respectively, for the three groups 7a, 7b, 7c can arbitrarily be carried out separately for one group or simultaneously for two or for all three groups 7a, 7b, 7c. Several or all tension members 3 of the support means 2 can thus be analyzed or monitored simultaneously, in that the device 1 only has to be analyzed a few times or even only once.

(22) In the alternative, the above-specified explanations can be illustrated by means of the Tables below. One example for a test for the tension member groups 7a is illustrated in Table-1, when all tension members 31, 32, 33, 34 are in a good state.

(23) TABLE-US-00001 TABLE 1 tension members in a good state tension input member signal 31 100001 32 010001 sum evaluate 33 001001 111101 OK 34 000101

(24) One example for a test for the tension member group 7a is illustrated in Table-2, if there is damage, such as, e.g. a break or penetration exist in the case of at least one tension member 31, 32, 33, 34.

(25) Table-2: error in one or several tension members

(26) TABLE-US-00002 TABLE 2 error in one or several tension members tension input sum evaluate member signal 31 100001 011101 error in 31 32 010001 101101 error in 32 33 001001 110101 error in 33 34 000101 111001 error in 34 101001 error in 32 and 34 001001 error in 31, 32 and 34

(27) A further example for a test of the tension member group 7a is illustrated in Table-3, when there is damage in the tension member 32. Different errors can occur thereby. In the case of a short circuit, an “X” could result on the second connection 3B of the tension member 32, in the case of a penetration or a resistance, which is too high, a second binary number “000001” could result, in the case of a resistance, which is too low, a second binary number “111101” could result, and in the case of a faulty transmission, such as, e.g. a delay, “001001” could result. Depending on what kind of error occurs, an error can either be determined for the concrete tension member 32 or for the group 7a or for the support means 2.

(28) TABLE-US-00003 TABLE 3 error in the tension member 32 tension input output member signal signal 31 100001 100001 sum evaluate 32 010001 000001 101101 error in 32 001001 X01 error in group 7a 111101 X error in the X support means 33 001001 001001 34 000101 000101

(29) The above-illustrated method or the device 1, respectively, can be carried out or activated, respectively, separately for an individual tension member 3 of the support means 2 or in part or simultaneously to all for the entire tension member 3 of the support means 2, both manually and automatically, when the elevator system is out of service, e.g., is in a maintenance or installation state, or in a waiting period (standby).

(30) In summary, embodiments of the method introduced herein or of the device 1 introduced herein, respectively, allow the detection of damage within the support means 2 or the tension members 3, respectively, using a digital electronics in a reliable manner. Slight damage within the support means 2 can already be detected by means of a fine setting of the pulse generator 9, such as, e.g. the period duration, scanning or level, so that the output signal 5 or the second binary number 5B, respectively, can still be detected plausibly as a result of the associated changes of the ability to transmit signals in the damaged tension member 3.

(31) Lastly, it is important to point out that terms, such as “having”, “comprising”, etc. do not exclude other elements or steps, and a term, such as “one” do not absolutely exclude a plurality. It is further important to point out that features or steps, which have been described with reference to one of the above exemplary embodiments, can also be used in combination with other features or steps of other above-described exemplary embodiments.

(32) It is pointed out that possible features and advantages of exemplary embodiments of the invention are described herein in part with reference to a method according to the invention and in part with reference to a device according to the invention. A person of skill in the art will recognize that the individual features can be combined in a suitable manner, can be modified or exchanged and that features, which are in particular described for the method, can analogously be transferred to the device, and vice versa, in order to get to further embodiments of the invention.

(33) In accordance with the provisions of the patent statutes, the present invention has been described in what is considered to represent its preferred embodiment. However, it should be noted that the invention can be practiced otherwise than as specifically illustrated and described without departing from its spirit or scope.

LIST OF REFERENCE NUMERALS

(34) 1 device for an elevator system 2 support means 3 tension member 31, 32, 33, 34 grouped tension members 3A the first connection of the tension member 3B the second connection of the tension member 4 digital input signal 4B the first binary number 4C the first extra digit 4D the second extra digit 5 digital output signal 5B the second binary number 6 analog signal 7 group of the tension members 7a, 7b, 7c three groups of the tension members 9 pulse generator 10 detector 11 processor 12 fault indicator 13 control unit or monitoring center/maintenance center 14 setpoint binary number 16 signal source 17 sum 18 network 19 synchronization