JPH11325844A - Diagnosis method of wire rope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable easy check of the whole length of a wire rope and simple diagnosis of disconnection of a wire and abrasion loss before rupture of a wire rope, by arranging a projector and a light receiver on both sides of the wire rope, and measuring light receiving amount by the light receiver while the wire rope is moved. SOLUTION: This diagnosis equipment comprises an optical sensor 20a such as a projector 1 and a light receiver 2 which are arranged on both sides of a wire rope 3, a signal processing part and a display part. A luminous flux generated from the projector 1 travels toward the light receiver 2. Since the wire rope 3 exists between the projector 1 and the light receiver 2, the light receiving amount of the light receiver 2 changes in accordance with the state of deterioration of the wire rope 3. By examining the change of the light receiving amount, the state of deterioration of the wire rope 3 can be known. When the diagnosis equipment is retained by a crane girder the wire rope 3 moves between the parts of the diagnosis equipment, and the state of deterioration in a length range of the wire rope can be diagnosed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for diagnosing deterioration of a wire rope used in a crane, an elevator or the like.

[0002]

2. Description of the Related Art A wire rope such as a crane and an elevator repeatedly lifts and hangs a heavy object, and the wire rope passes through a winding drum or a pulley. Due to considerable bending, repeated bending fatigue is severe. Therefore, the accumulation of fatigue and the progress of damage are large. Therefore, if a heavy load or a passenger cage falls due to breakage of the wire rope, the lives of workers and passengers are put at risk, and great damage is caused by damage to equipment.

[0003] Therefore, it is very important to accurately predict the replacement time of the wound wire rope. Conventionally, the replacement time of this type of wire rope is set based on the operating time of the crane and the elevator, the result of investigation of the residual strength of the wire rope, etc., and the winding time is set. The replacement time was estimated based on the cumulative operating time of the data. However, due to fear of dropping of a suspended load or a cage due to fatigue rupture of the wire rope, replacement is often performed much earlier than the actual life of the wire rope in consideration of safety. Repair costs related to the rope were increasing.

[0004] In order to reduce the repair cost, various methods have been proposed for predicting the replacement time of the wire rope.

[0005] The first is the winding of a wire rope,
Measure the number of bends due to lowering, applied load, wire rope tension, etc., and based on those measured values, wire rope
Japanese Patent Application Laid-Open No. Hei 5 (1993), which calculates the fatigue level of a pump, and further calculates the cumulative fatigue level by integrating the fatigue levels to predict the replacement time.
No. 39187.

Secondly, at least one strand with an insulating coating is incorporated in each strand constituting the wire rope, and each of the strands with an insulating coating is controlled to be insulated from the presence or absence of the energized state. A wire disconnection circuit that detects a break in the covered wire, and a voltage is applied through another strand wire that is not insulated from the insulated covered wire,
Japanese Patent Application Laid-Open No. Sho 62-123368 for predicting the replacement time by obtaining the degree of damage of a wire rope from the insulation state.
There is a number.

[0007] Third, a permanent magnet for magnetizing the wire loop to near the saturation point, a detection head including a detection element for detecting leakage magnetic flux from the rope, an output circuit, and the like are provided. Japanese Unexamined Patent Publication No. Hei 7-137985: detecting the amount of change in leakage magnetic flux when a wire breaks in a rope, obtaining the degree of damage to the wire rope, and predicting the replacement time;
There is a number.

Fourth, a tubular sensor having a magic tape attached to its inner surface is provided. When a break occurs in the wire rope, the broken wire is caught on the magic tape and the sensor is connected to the wire rope. Japanese Patent Application Laid-Open No. Sho 56-56, which is pulled in one of the upper and lower directions together with a loop, and a limit switch is actuated via a lead loop connected to a sensor;
No. 69574.

Fifthly, an imaging means and a signal analysis means are provided around the wire rope to detect breakage, abrasion, corrosion and the like of the wire rope from the video analysis data. JP-A-2-56397.

[0010]

However, the above-described techniques relating to the estimation of the life of the wire rope and the detection of the degree of damage have the following problems.

The first technique requires special equipment for measuring the applied load and the tension, and generally requires a large capital investment because the means for measuring the number of times of bending and for calculating the degree of fatigue are complicated. In addition, the relationship between the radius of curvature of the winding drum, pulley, etc. and the amount of transient load fluctuation and the degree of fatigue is unclear, and this method does not reflect the manufacturing error of the wire rope and the accuracy is not good. .

In the second technique, it is necessary to manufacture a special wire rope coated with insulation, which increases the purchase cost of the wire rope. Further, in addition to the damage degree calculating device, a current control device for the wire rope is required, which is not practical.

The third technique is the first technique and the second technique.
It can be said to be a method that can be realized at a relatively low cost compared to the technique of the above. However, this technique is presumed to be a method with low detection accuracy for the following reasons. That is, in the detection of wire breakage of the wire rope, the wire-wire diameter is very small as compared with the eddy current sensor, so that the change in magnetic flux due to wire breakage is expected to be small. In addition, wire
It is difficult to detect wear and deformation of the loop. This is because the characteristics of the magnetic sensor greatly change depending on the distance to the object to be measured. Therefore, when the wire rope is worn or kinked, or when the wire rope is shaken, the magnetic sensor is used. This is because the distance between-and the object to be measured greatly changes.

The fourth technique can be said to be a method which can be realized at a lower cost than the first to third techniques. But,
Since the broken wire is caught by the magic tape and operates, it is relatively effective for detecting wire wire breakage, but is useful for detecting wire rope abrasion and deformation. Is not available.

The fifth technique requires a great deal of man-hours to attach and detach the detector and uses expensive equipment, so that the capital investment is larger than any of the above-mentioned methods. Therefore, it cannot be used permanently for each crane or the like. In addition, if a user carries a measuring device and tries to make a periodic diagnosis, a large number of man-hours will be required for mounting and removing the detector, resulting in a large equipment downtime and a large repair cost, which is not a practical method.

The present invention has been made to solve the above-mentioned various problems, and the entire length of the wire rope can be easily inspected.
It is another object of the present invention to provide a method for simultaneously and simply diagnosing a broken wire state, a wear amount, and a shape collapse of a wire before a wire rope is broken.

[0017]

The present invention achieves the above object by the following method.

A first method comprises the steps of disposing a light emitter and a light receiver on both sides of a wire rope with a wire rope therebetween,
A method of diagnosing a wire rope, comprising the steps of measuring the amount of light received by the light receiver while moving the rope, and diagnosing the damage of the wire rope based on a change in the measured value of the amount of light received.

The second method is a method for diagnosing a wire rope according to claim 1, wherein the step of diagnosing the damage state of the wire rope comprises at least one of the following steps.

(A) A step of passing a measurement signal of the amount of received light through a high-pass filter and diagnosing a wire-rope wire break from the obtained signal value.

(B) A step of passing a measurement signal of the amount of received light through a high-pass filter and diagnosing the amount of wear and deformation of the wire rope from the obtained signal value.

A third method is a step of judging the level of a detection signal value of a sensor for detecting a state of deterioration of a wire rope such as a broken wire, abrasion, and shape loss, and wirelessly transmitting the judgment result to a monitoring center. -Transmitting to a wire-b
It is a diagnosis method of the loop.

A fourth method is a wire-loop diagnosis method according to the second method, wherein a step of determining good, cautious, or bad for each wire-loop is added to the step of determining a level.

In a fifth method, a plurality of deterioration state detection sensors are attached to a wire rope of each device, and a monitoring center is connected via a relay antenna for receiving a detection signal of each sensor.
Processes the signals transmitted by radio and received by the monitoring center,
This is a wire-loop diagnosis method for judging and displaying the result.

The sixth method is the same as the fifth method, except that the operating power of the deterioration state detecting sensor and / or the relay antenna is changed to an airframe such as a crane, an elevator, or a wire-lower.
Power generation device composed of a ceramic element or the like that generates electric power by utilizing the vibration of a loop, a row rotating in contact with a wire rope
Power generated by at least one of a rotary generator that generates electric power by the rotational force of a rotor, a body such as a crane and an elevator, or a movable magnet generator that generates electric power by using vibration of a wire rope. A wire characterized by operating power
This is a method for diagnosing a rope.

[Operation] First method: The wire loop is moved, and the change in the measured value of the received light amount at that time is analyzed with the lapse of time.
It is possible to know the state of damage such as abrasion of the rope and the breakage of the wire, and the location of the damage.

Second method: When the measurement signal of the amount of received light is passed through a high-pass filter and its change with time is analyzed, the broken wire and the abrasion amount and shape of the wire rope can be found. In addition, the positions at which they occur can be known.

Third and fourth methods: The degree of damage to the wire rope can be known at the monitoring center.

Fifth method; multiple wires of multiple devices-
The monitoring center can determine the degree of damage to the rope.

[0030]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a positional relationship between a sensor and a wire rope according to the present invention, FIG. 2 is a diagram showing a sensor-output signal processing circuit and a display according to the present invention, and FIG. FIG. 4 is a perspective view showing a mounting position of a crane of a sensor according to the present invention on a wire rope.

The diagnostic apparatus 20 according to the present invention comprises sensors 20a such as a light projector 1 and a light receiver 2 provided with a wire loop 3 to be diagnosed interposed therebetween, signal processing, and a display unit.
The sensor 20a includes a laser sensor and a CCD image sensor.
An optical sensor such as a di-sensor or a sensor having a photodiode type light receiver is used. A light beam 4 emitted from the light projector 1 travels toward the light receiver 2. Since there is a wire rope 3 between the light emitter 1 and the light receiver 2,
Deterioration status of rope 3 (cut wire, abrasion, shape collapse, elongation)
As a result, the amount of light received by the light receiver 2 changes. By examining the change in the amount of received light, the state of deterioration of the wire rope 3 can be known.

As shown in FIG. 3, the diagnostic device 20 is a
If the take-up drum 23 is rotated, the wire rope 3 moves between the diagnostic devices 20 if the take-up drum 23 is supported. Therefore, it is possible to diagnose the deterioration of the length range of the wire rope passing through the diagnostic device 20. Reference numeral 22 denotes a sheave block. When one set of the diagnostic device 20 is mounted on a winding wire rope such as a crane, the broken wire is the upper and lower outer peripheral tangents of the outer periphery of the wire rope parallel to the optical axis direction of the sensor. When it protrudes into the region S (the shaded region in FIG. 1) S, a broken wire cannot be detected. However, when a wire break occurs, it is randomly generated at the outer peripheral position of the wire rope, and the tip of the broken wire almost jumps out of the region S. 10% or more of wire breakage is used as a guide for wire rope replacement according to safety rules such as safety rules. Therefore, it is not necessary to catch a state where wire breakage is extremely small at the beginning of disconnection. A set of sensors
Can be attached. However, if it is necessary to catch the broken wire state at the beginning of the disconnection, the number of sensors may be increased as appropriate.

FIG. 2 shows a signal processing / display circuit of a sensor output for detecting the deterioration state of the wire rope 3 described above.
This will be described below. A sensor output signal including a signal relating to wire break, abrasion, deformation and elongation of the wire rope is sent to a wire break detection circuit, a wear / shape detection circuit and an elongation detection circuit.

In the wire break detection circuit, first, a frequency band is selected by a high-pass filter (HPF) of 50 Hz or a band-pass filter (BPF1) 5a of 50-500 Hz, and smoothed by a rectifier circuit (REC) 6a. It is transmitted to the rear comparator (COMP) 7a. The signal is compared with the reference value by the comparator (COMP) 7a. If the signal exceeds the reference value, a current flows through the red lamp circuit by the switch (MUX) 8a, and the red lamp (RL) is turned on. In the following cases, a current flows through the blue lamp circuit by the switch (MUX) 8a, and the blue lamp (GL) is turned on.

In the wear / deformation detection circuit, first, a frequency band is selected by a low-pass filter (LPF) of 5 Hz or a band-pass filter (BPF2) 5b of 0.1-5 Hz, and a rectifier circuit (REC). After being smoothed in 6b, it is transmitted to a comparator (COMP) 7b. The signal is compared with a reference value by a comparator (COMP) 7b. If the signal exceeds the reference value, a current flows through a red lamp circuit by a switch (MUX) 8b, and the red lamp (RL) is turned on, and the signal is below the reference value. In this case, current flows through the blue lamp circuit by the switch (MUX) 8b, and the blue lamp (GL) is turned on.

In the elongation detection circuit, a frequency band of a band-pass filter (BPF4) of 5-20 Hz is selected, smoothed by a rectifier circuit (REC) 6c, and then output from a comparator (C).
OMP) 7c. Comparator (COMP)
7c, the initial twist pitch of the wire rope immediately after the replacement of the wire loop, which is input in advance, is compared with the measured twist pitch obtained by analyzing the frequency component (pitch frequency) of the transmitted signal; When the reference value is exceeded, a current flows through the red lamp circuit by the switch (MUX) 8c, and the red lamp (RL) lights up. When the reference value is not exceeded, a current flows through the blue lamp circuit by the switch (MUX) 8c. , The blue lamp (GL) is turned on.

The signal processing from the sensor can be implemented by software processing instead of the above-described hard processing.

Although the embodiments of the present invention have been described in detail above, the above-mentioned filter constants generally describe optimum values in the crane, and may slightly deviate from these values. Absent. Further, the accuracy of diagnosis is improved by switching the above-mentioned filter constant in accordance with the winding speed of the wire rope, estimating the charge from the current of the winding motor, and diagnosing under a constant load condition. .

Next, as an example obtained by the above signal processing, waveform data obtained by measuring the outer diameter of a wire rope using a laser sensor, and frequency analysis of the measured data are obtained. The obtained frequency spectrum will be described with reference to FIGS.

FIG. 4 shows waveform data of a normal wire rope, and shows a state where the wire is wound at a wire speed of 300 mm / sec. The horizontal axis represents time, and the vertical axis represents the size of the outer diameter. There is no disturbance in the waveform at all, and only the frequency component of the light quantity change corresponding to the pitch component of the twist of the wire rope is well represented. FIG. 5 is a frequency spectrum obtained by performing frequency analysis on waveform data of a normal wire rope shown in FIG. The frequency component of the wire rope is equivalent to the pitch component of the twist.
Hz.

FIG. 6 shows the waveform data of the wire rope in which the wire break has occurred. The wire break portion A can be clearly seen. FIG. 7 shows the frequency spectrum, and it can be seen that the frequency component at the wire break is mainly at 115 to 130 Hz. FIG. 8 shows waveform data of a wire rope having large wear. FIG. 9 is a frequency spectrum, in which 9a is a wire rope having a large amount of wear, and 9b is a normal wire rope. When the wear is large (9a) compared to the spectrum at the normal time (9b), the wear (range: B-
Due to the diameter reduction by C), the frequency component corresponding to the twist pitch component of the wire rope is reduced by about 20 Hz, and is newly added to about 1 Hz.
It can be seen that the component is mainly used.

FIG. 10 is a block diagram for explaining a method of diagnosing a wire loop in the monitoring center. Four cranes # 1 to # 4 are arranged in the A yard, and three cranes # 5 to # 7 are arranged in the B yard. Sensors 25a to 25h are attached to the # 1 to # 7 crane, respectively. The A yard has three relay antennas 26a to 26c.
However, the B yard has two relay antennas 26d and 26e.
Is provided. 27 is an abnormality monitoring monitor of the monitoring center. The abnormality monitoring monitor 27 includes a crane number and a sensor attached to a wire rope of each crane.
The signal from each sensor and the signal from each sensor are processed by the above-described method, and the signal values relating to wire breakage, abrasion, shape collapse and elongation of each wire rope are compared with a reference value.
And a display means for displaying a determination result from the determination means. The judgment means may judge the deterioration level of the wire loop in two levels of "good" and "defective". However, the judgment is made in three levels of "good", "caution" and "poor". It is desirable to make it.

With the above-described equipment, the wire of each crane
Diagnosis of the deterioration state of the pump is performed as follows.

(1) Each sensor of the cranes of each yard
(Eg, # 1 crane sensor 25a) wirelessly transmits a detection signal to a relay antenna (eg, relay antenna 26a).

(2) The signal received by the relay antenna is transmitted to the abnormality monitoring monitor 27 of the monitoring center.

(3) The signals are classified by the discriminating means of the signal sensor and sent to the judging means to judge the deterioration level of each deterioration item.

(4) The signal of the deterioration level is sent to the display means, and "good", "caution", and "bad" are displayed for each sensor. As a display method, there is a method of constantly displaying information and a method of accumulating information for a certain period of time and performing intermittent display.

[0048]

According to the present invention, the following effects can be obtained.

(1) Deterioration states such as wire breakage, abrasion, shape collapse and elongation can be easily checked over the entire length of the wire rope.

(2) It is possible to predict the optimal time for replacing the wire rope, and to prevent an unexpected accident due to oversight of deterioration. As a result, the wire ro
Repair costs, such as purchase and replacement costs of the pump, can be minimized.

(3) According to the method of the fifth aspect, it is possible to constantly monitor the deterioration of the wire rope of many crane, elevator and the like. In particular, it is possible to improve the safety of the automatic crane, which cannot be easily accessed by persons other than regular repairs, and to reduce the labor required for the maintenance inspection by the maintenance man or the operator.

(4) According to the method of claim 6, power consumption can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a positional relationship between a sensor and a wire rope according to the present invention.

FIG. 2 is a diagram showing a sensor-output signal processing circuit and a display device according to the present invention.

FIG. 3 is a perspective view showing a mounting position of a crane of a sensor according to the present invention on a wire rope.

FIG. 4 shows a normal wire ro obtained by the method of the present invention.
This is a chart of waveform data of a loop.

FIG. 5 is a frequency spectrum diagram obtained by frequency-analyzing the waveform data of FIG. 4;

FIG. 6 is a chart of waveform data of a wire rope having a broken wire obtained by the method of the present invention.

FIG. 7 is a frequency spectrum diagram obtained by performing frequency analysis on the waveform data of FIG. 6;

FIG. 8 is a chart of waveform data of a worn wire rope obtained by the method of the present invention.

9 is a frequency spectrum diagram (9a) obtained by frequency analysis of the worn waveform data of FIG. 8 and a frequency spectrum obtained by frequency analysis of the normal waveform data of FIG. It is a figure (9b).

FIG. 10 is a system diagram showing a method of diagnosing a wire loop in a monitoring center.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 Projector 2 Receiver 3 Wire loop 4 Beam bundle 5a-5c High or low pass filter or band pass filter 6a-6c Rectifier circuit 7a-7c Comparator 8a-8c Switching device 9 Blue lamp 10 Red lamp Reference Signs List 20 diagnostic device 20a sensor 25a to 25h sensor 26a to 26e relay antenna 27 abnormality monitoring monitor

Claims (6)

[Claims] 1. A step of arranging a light emitter and a light receiver on both sides of a wire rope between them, a step of measuring an amount of light received by the light receiver while moving the wire rope, and A method for diagnosing a wire rope, comprising the step of diagnosing a wire rope damage condition based on a change in a measured value of an amount. 2. The method according to claim 1, wherein the step of diagnosing the damage state of the wire rope comprises at least one of the following steps. (A) A step of passing a measurement signal of the amount of received light through a high-pass filter and diagnosing a wire rope breakage from the obtained signal value. (B) A step of passing a measurement signal of the amount of received light through a high-pass filter and diagnosing the amount of wear and deformation of the wire rope from the obtained signal value. 3. A step of judging the level of a detection signal value of a sensor for detecting a state of deterioration of a wire rope such as a broken wire, abrasion, or shape loss thereof, and wirelessly transmitting the judgment result to a monitoring center.
And transmitting to the wire loop. 4. The method for diagnosing a wire loop according to claim 3, further comprising a step of determining good, cautious, or bad for each wire loop in the step of determining the level. 5. A plurality of deterioration state detection sensors are attached to a wire loop of each device, each deterioration state detection sensor is divided into groups, and a detection signal of each group sensor is received. A method for diagnosing a wire loop, comprising: transmitting a signal wirelessly to a monitoring center via a relay antenna, processing and judging a signal received by the monitoring center, and displaying a result; 6. The method according to claim 5, wherein the operating power of the deterioration state detection sensor and / or the relay antenna is crane.
A power generation device including a ceramic element or the like that generates power by using vibration of a body such as an elevator or a wire rope;
A rotary generator that generates electric power by the rotational force of a roller that rotates in contact with a wire rope, a machine such as a crane or an elevator, or a movable unit that generates electric power by using vibration of a wire rope. A method for diagnosing a wire loop, wherein at least one generated power of a magnet type generator is used as the operating power.