CN111776916A - Method and device for detecting strand breakage of elevator traction steel belt - Google Patents
Method and device for detecting strand breakage of elevator traction steel belt Download PDFInfo
- Publication number
- CN111776916A CN111776916A CN202010738910.5A CN202010738910A CN111776916A CN 111776916 A CN111776916 A CN 111776916A CN 202010738910 A CN202010738910 A CN 202010738910A CN 111776916 A CN111776916 A CN 111776916A
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- steel wire
- detection device
- steel belt
- pulse
- traction steel
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
- B66B7/00—Other common features of elevators
- B66B7/06—Arrangements of ropes or cables
- B66B7/062—Belts
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
- B66B7/00—Other common features of elevators
- B66B7/12—Checking, lubricating, or cleaning means for ropes, cables or guides
- B66B7/1207—Checking means
- B66B7/1215—Checking means specially adapted for ropes or cables
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
- B66B7/00—Other common features of elevators
- B66B7/12—Checking, lubricating, or cleaning means for ropes, cables or guides
- B66B7/1207—Checking means
- B66B7/1215—Checking means specially adapted for ropes or cables
- B66B7/1223—Checking means specially adapted for ropes or cables by analysing electric variables
Landscapes
- Maintenance And Inspection Apparatuses For Elevators (AREA)
- Lift-Guide Devices, And Elevator Ropes And Cables (AREA)
Abstract
The invention discloses a method for detecting strand breakage of an elevator traction steel belt, which comprises the following steps: the tail end of the traction steel belt is in short connection with each strand of steel wire rope in pairs by using a steel wire clamp, and the head end of the traction steel belt is connected with a detection device; the detection device sequentially sends pulse signals to each steel wire rope, and detects the pulse width, the period and the pulse number of echo signals of other steel wire ropes; calculating the error percentage of each echo signal and the sent pulse signal; and comparing the error percentage with a preset threshold value, and judging whether the error percentage is within a normal range, if so, judging that the steel wire rope corresponding to the received pulse signal is not stranded, and if not, judging that the steel wire rope corresponding to the received pulse signal is stranded. The utility model provides an elevator tows disconnected thigh detection device of steel band, includes: the pulse collector collects echo signals sent by the micro control unit and transmits the echo signals to the micro control unit. The invention has the advantages of high detection efficiency and good detection effect.
Description
Technical Field
The invention relates to the technical field of elevator control, in particular to a method and a device for detecting strand breakage of an elevator traction steel belt.
Background
At present, in the market, an elevator traction steel belt is used as a new transmission technology to replace the common steel wire rope transmission to be applied to the bearing of equipment such as elevators, and is produced and sold by a plurality of elevator manufacturers. The elevator traction steel belt is structurally different from a common steel wire rope, and the steel wire rope can not be observed by naked eyes because the steel wire rope is partially wrapped by polyurethane, so that the fracture condition of the steel wire rope in the elevator traction steel belt can not be judged by manual detection or a detection tool special for the steel wire rope.
At present, in the prior art, a steel wire rope detector is used as a main tool for detecting steel wire ropes, so that the normal operation of the steel wire ropes is ensured, and the steel wire rope detector is widely applied to the detection of steel wire ropes of ports, hoist cranes and elevators. The steel wire rope detector adopts the permanent magnet and magnetic flux leakage principle. During detection, the steel wire rope is saturated magnetically by a group of permanent magnets. Then, the magnetic head wraps the steel wire rope to run relatively at a constant speed. Any defects on the surface of the steel wire rope, such as wire breakage, abrasion, corrosion and the like, can cause the change of magnetic flux leakage and magnetic flux, so that the magnetic flux is captured by the Hall sensor and converted into an electric signal, and a visual analog signal is output.
However, the magnetic head wraps the steel wire rope and runs on the steel wire rope at a constant speed, operation is troublesome in actual detection, when a long steel belt is encountered, the magnetic head needs to move from one end of the steel wire rope to the other end, and detection efficiency needs to be improved. Therefore, the problems of low detection efficiency and troublesome operation of the steel wire rope detector in the prior art become a technical problem to be solved urgently.
Disclosure of Invention
The invention aims to provide a method and a device for detecting strand breakage of an elevator traction steel belt, which have the advantages of high detection efficiency and good detection effect, are convenient to detect the steel belt and simple in wiring, avoid measurement errors caused by resistance value changes of a steel wire rope in the using process, and improve the measurement accuracy of the steel belt.
In order to solve the technical problems, the technical scheme provided by the invention is as follows: a method for detecting strand breakage of an elevator traction steel belt comprises the following steps: the tail end of the traction steel belt is in short connection with each strand of steel wire rope in pairs by using a steel wire clamp, and the head end of the traction steel belt is connected with a detection device; the detection device sequentially sends pulse signals to each strand of steel wire rope and detects the pulse width, the period and the pulse number of echo signals of other strands of steel wire ropes; calculating the pulse width, the period and the number of pulses of each echo signal and the error percentage of the sent pulse signals; and comparing the error percentage of each strand in each period with a preset threshold value, judging whether the error percentage is in a normal range, if so, judging that the steel wire rope corresponding to the received pulse signal is not broken, and if not, judging that the steel wire rope corresponding to the received pulse signal is broken.
By adopting the technical scheme, each strand of steel wire rope at the tail end of the traction steel belt is in short circuit in pairs through the steel wire clamp, echo signals fed back by the other strands are sequentially detected after the pulse signals are sent out by the detection device at the head end, and whether the error percentage of the echo signals and the sent pulse signals and the preset threshold value belong to the normal range or not is calculated and judged, so that whether the steel wire rope is broken or not can be conveniently and quickly detected.
According to the method for detecting the strand breakage of the elevator traction steel belt, the detection device sequentially sends a group of pulse signals with fixed frequency and pulse width at the head end of the traction steel belt, and then sequentially detects echo signals of the sent pulse signals on the other steel wire ropes. The pulse signal has strong anti-interference capability in the transmission process, the stability of the detection signal is ensured, and the detection precision is improved.
According to the method for detecting the strand breakage of the elevator traction steel belt, when the number of the steel wire ropes with correct echo signals received by the detection device is less than 2, each strand of the steel wire ropes of the traction steel belt is judged to be the strand breakage. The strand breaking condition of each strand is conveniently known by detecting the number of returned echo signals and according to the condition of the returned echo signals of each strand.
According to the detection method for the strand breakage of the elevator traction steel belt, the echo signal returns to the micro control unit of the detection device through the protection device. The protection device is used for limiting the current and the voltage of the echo signal and preventing the detection device from being damaged by the overlarge voltage and current.
In order to solve the above technical problem, the present invention further provides another technical solution: the utility model provides an elevator tows disconnected thigh detection device of steel band, includes: the micro control unit is used for sending out a detection pulse signal, receiving a returned echo signal, and calculating and judging a comparison result of the echo signal and a preset threshold value; the protection device is used for limiting current and voltage of the echo signals; and the pulse collector is used for collecting the echo signal in the protection device and transmitting the echo signal to the micro control unit.
According to the technical scheme, the micro control unit MCU is used for sending the pulse signal and receiving the echo signal, and the comparison result of the error percentage of the echo signal and the preset threshold value is calculated and judged, so that whether strand breakage exists in the elevator traction steel belt or not is detected.
The elevator traction steel belt strand breakage detection device further comprises a steel wire clamp which connects the tail ends of the traction steel belts in a two-to-two short connection mode. The tail ends of the traction steel belts are in short connection in pairs through the steel wire clamps.
According to the elevator traction steel belt strand breakage detection device, the micro control unit is connected with the cascade pulse collector through signals. And the cascade pulse collector is used for establishing a cascade relation, connecting a plurality of devices and detecting a plurality of traction steel belts simultaneously, and further improving the detection efficiency.
According to the elevator traction steel belt strand breakage detection device, the micro control unit is connected with the cascade detector through signals. The cascade detector is used for informing the micro-control unit whether a cascade device exists.
The elevator traction steel belt strand breakage detection device is characterized in that the micro control unit is in signal connection with a safety relay. And the signal connection safety relay is used for reporting the detection data and the state of the detection device to the steel strip.
According to the elevator traction steel belt strand breakage detection device, the micro control unit is independently externally provided with the hardware watchdog circuit. The independent hardware watchdog circuit is independent of the MCU and used for controlling the safety relay to report a fault state when the input/output port of the MCU is in fault so as to prompt the controller to be in fault and to be repaired.
The beneficial effects obtained by the invention are as follows:
1. the detection cost is low: compared with the scheme of visual detection and resistance measurement, the invention can greatly reduce the material cost of the circuit and the field wiring difficulty, has simple maintenance and provides a detection basis for the safety detection and the later maintenance of the elevator traction steel belt.
2. The expansion is convenient: the cascade detector of the detection unit can be adjusted to realize the simultaneous detection of a single steel strip to a plurality of steel strips, so that a plurality of detection units can be expanded, and the detection efficiency is improved.
3. The invention uses the pulse signal to poll each strand of steel wire rope of the steel belt, has more reliable and safe scheme and strong anti-interference capability, avoids the condition of misjudgment of the broken strand of the steel belt caused by the damage of the I/O port of the detection device due to strong electric interference, and ensures the detection accuracy.
4. The invention introduces the independent hardware watchdog circuit, when the detection device is in fault, the independent hardware watchdog circuit is independent of the detection device, controls the safety relay to report the fault state and timely informs the controller device that the fault occurs and the maintenance is needed, ensures the accuracy of detecting the broken strand of the steel strip and simultaneously improves the safety use performance of the detection device.
Drawings
FIG. 1 is a schematic diagram of the system structure of the elevator traction steel belt strand breakage detection device;
FIG. 2 is a schematic view of the traction steel belt input detection principle of the present invention;
FIG. 3 is a schematic diagram of the pulse signal and echo signal transmission and return for detecting steel strip according to the present invention;
FIG. 4 is a schematic view of a connection structure for simultaneously detecting a plurality of steel strips according to the present invention;
FIG. 5 is a schematic diagram of a normally open circuit of a relay for a cascade application of the present invention;
fig. 6 is a schematic circuit diagram of a normally closed circuit of a relay in cascade application of the present invention.
Description of reference numerals: the system comprises a micro control unit 1, a protection device 2, a pulse collector 3, a cascade pulse collector 4, a cascade detector 5, a safety relay 6, a hardware watchdog circuit 7, a steel wire clamp 8, a traction steel belt 9, a detection device 10 and a controller 11.
Detailed Description
The invention is further described with reference to the following figures and detailed description.
The invention discloses a method for detecting strand breakage of an elevator traction steel belt, which comprises the following steps:
the tail end of a traction steel belt 9 is in short connection with each strand of steel wire rope in pairs by using a steel wire clamp 8, and the head end of the traction steel belt 9 is connected with a detection device 10;
the detection device 10 sequentially sends pulse signals to each strand of steel wire rope, and detects the pulse width, the period and the pulse number of echo signals of other strands of steel wire ropes;
calculating the pulse width, the period and the number of pulses of each echo signal and the error percentage of the sent pulse signals;
and comparing the error percentage of each strand in each period with a preset threshold value, judging whether the error percentage is in a normal range, if so, judging that the steel wire rope corresponding to the received pulse signal is not broken, and if not, judging that the steel wire rope corresponding to the received pulse signal is broken.
The detection device 10 sequentially sends a group of pulse signals with fixed frequency and pulse width at the head end of the traction steel belt 9, and then sequentially detects echo signals of the sent pulse signals on the other steel wire ropes.
When the number of the wire ropes receiving the correct echo signals by the detection device 10 is less than 2, each strand of the wire rope of the traction steel belt 9 is judged to be broken.
The echo signals are returned via the protective device 2 to the microcontroller unit 1 of the detection device 10.
Referring to fig. 1 to 6, the present invention also discloses an elevator traction steel belt strand breakage detection apparatus, including:
the micro control unit 1 is used for sending out a detection pulse signal, receiving a returned echo signal, and calculating and judging a comparison result between the echo signal and a preset threshold value;
the protection device 2 is used for limiting current and voltage of echo signals;
and the pulse collector 3 is used for collecting the echo signal in the protection device 2 and transmitting the echo signal to the micro control unit 1.
Further, the detection device also comprises a steel wire clamp 8 which connects the tail ends of the traction steel belts 9 in a form of short connection in pairs. In practical use, the short circuit of the tail end of the traction steel belt 9 can be realized through the steel wire clamp 8 in the embodiment, or through other methods such as short circuit of the steel wire of the traction steel belt 9 by using a wire, short circuit by welding, and the like, depending on practical situations.
As shown in fig. 1, 2 and 3, the micro control unit 1 sends a pulse signal to the elevator traction steel belt, the elevator traction steel belt is in short circuit two by two through the steel wire clamp 8, the micro control unit 1 polls each strand of steel wire rope of the steel belt, outputs a group of pulse signals with fixed frequency and pulse width in one steel wire rope in sequence, then detects the pulse signals with fixed frequency and pulse width in other remaining steel wire ropes in sequence, and when a correct pulse signal is detected, it indicates that the steel wire rope with the correct signal detected by the circuit is complete.
After the cascade connection is established, the detection device 10 can send out a state pulse to the upper detection device 10 and finally to the controller 11 of the elevator so as to display the broken condition of the steel belt of the current level, such as the broken condition of single or multiple strands.
In the present embodiment, the micro control unit 1 is connected to a cascade pulse collector 4, a cascade detector 5, and a safety relay 6 through signals. Further, as shown in fig. 4, 5 and 6, the safety relay 6 uploads the detection state and detection result of the detection device 10 to the controller 11 through its normally open contact or normally closed contact, specifically, when the elevator controller 11 selects the normally closed mode, the connection mode is as shown in fig. 5, and the normally open contact of each relay on the circuit is required to be closed, indicating normal operation; when a fault occurs in a certain path, the corresponding relay is disconnected, the normally open contact is disconnected, and the elevator controller 11 can detect that the path has the fault. When the elevator controller 11 adopts a normally open mode, the connection mode is as shown in fig. 6, and normally closed contacts of relays on a circuit are required to be opened, so that normal operation is represented; when a certain path has a fault, the corresponding relay is closed, the normally closed contact is closed, and the elevator controller 11 can detect that the path has the fault. It should be understood that the safety relay 6 connects a plurality of micro control units 1 to form a relay loop, and the elevator controller receives corresponding actions of the relay through actions of normally open or normally closed contacts of the relay so as to judge that the detection device 10 of a certain path has a fault.
The micro control unit 1 is independently externally provided with a hardware watchdog circuit 7.
The micro control unit 1 is connected with the cascade detector 5 and the cascade pulse collector 4 through signals, so that the detection device 10 can establish a cascade relation and simultaneously detect a plurality of traction steel belts, and the detection rate is improved; in the detection process, the number of the traction steel belts to be detected can be expanded through the step-by-step reporting mode of each detection device 10, and finally, the signals fed back by each detection device are reported to the controller host.
In summary, the actual samples of the present invention are prepared according to the description and the drawings, and after a plurality of usage tests, the effect of the usage tests proves that the present invention can achieve the expected purpose, and the practical value is undoubted. The above-mentioned embodiments are only for convenience of illustration and not intended to limit the invention in any way, and those skilled in the art will be able to make equivalents of the features of the invention without departing from the technical scope of the invention.
Claims (10)
1. A method for detecting strand breakage of an elevator traction steel belt is characterized by comprising the following steps:
the tail end of the traction steel belt (9) is in short connection with each strand of steel wire rope by using a steel wire clamp (8), and the head end of the traction steel belt (9) is connected with a detection device (10);
the detection device (10) sequentially sends pulse signals to each strand of steel wire rope, and detects the pulse width, the period and the pulse number of echo signals of other strands of steel wire ropes;
calculating the pulse width, the period and the number of pulses of each echo signal and the error percentage of the sent pulse signals;
and comparing the error percentage of each strand in each period with a preset threshold value, judging whether the error percentage is in a normal range, if so, judging that the steel wire rope corresponding to the received pulse signal is not broken, and if not, judging that the steel wire rope corresponding to the received pulse signal is broken.
2. The method for detecting strand breakage of an elevator traction steel belt according to claim 1, characterized in that: the detection device (10) sequentially sends a group of pulse signals with fixed frequency and pulse width at the head end of the traction steel belt (9), and then sequentially detects echo signals of the sent pulse signals on the other steel wire ropes.
3. The method for detecting strand breakage of an elevator traction steel belt according to claim 2, characterized in that: and when the number of the steel wire ropes with correct echo signals received by the detection device (10) is less than 2, judging that each strand of the steel wire ropes of the traction steel belt (9) is broken.
4. The method for detecting strand breakage of an elevator traction steel belt according to claim 1, characterized in that: the echo signals are returned to the microcontroller unit (1) of the detection device (10) via the protective device (2).
5. The utility model provides an elevator tows disconnected thigh detection device of steel band which characterized in that includes:
the micro control unit (1) is used for sending out a detection pulse signal and receiving a returned echo signal, and calculating and judging a comparison result between the echo signal and a preset threshold value;
the protection device (2) is used for limiting the current and the voltage of the echo signals;
and the pulse collector (3) is used for collecting the echo signals in the protection device (2) and transmitting the echo signals to the micro control unit (1).
6. The elevator traction steel belt strand breakage detection device according to claim 5, characterized in that: the steel wire clip (8) is used for connecting the tail ends of the traction steel belts (9) in a short connection mode.
7. The elevator traction steel belt strand breakage detection device according to claim 5, characterized in that: the micro control unit (1) is connected with a cascade pulse collector (4) through signals.
8. The elevator traction steel belt strand breakage detection device according to claim 7, characterized in that: the micro control unit (1) is connected with a cascade detector (5) through signals.
9. The elevator traction steel belt strand breakage detection device according to claim 5, characterized in that: the micro control unit (1) is in signal connection with a safety relay (6).
10. The elevator traction steel belt strand breakage detection device according to claim 9, characterized in that: the micro control unit (1) is independently externally provided with a hardware watchdog circuit (7).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010738910.5A CN111776916A (en) | 2020-07-28 | 2020-07-28 | Method and device for detecting strand breakage of elevator traction steel belt |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010738910.5A CN111776916A (en) | 2020-07-28 | 2020-07-28 | Method and device for detecting strand breakage of elevator traction steel belt |
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| CN111776916A true CN111776916A (en) | 2020-10-16 |
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| CN202010738910.5A Pending CN111776916A (en) | 2020-07-28 | 2020-07-28 | Method and device for detecting strand breakage of elevator traction steel belt |
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| CN212374654U (en) * | 2020-07-28 | 2021-01-19 | 江门市蒙德电气股份有限公司 | Elevator tows disconnected thigh detection device of steel band |
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