JPH115675A - Diagnostic device for magnet brake for elevator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a diagnostic device for a magnet brake for elevators, capable of securing such a diagnostic effect as being high in reliability at all times and also performing parts replacement and adjusting operations at an optimum point of time. SOLUTION: A diagnostic device 3 is composed of equipping a current detector 31 detecting a brake working current, an A/D converter 32 converting into digital signal this brake working current detected by the detector 31, a RAM 35 temporarily storing a current signal to be outputted by this converter 32, a ROM 34 storing initial state information extracted out of the brake working current at the time of the newly installation of a brake 27, a CPU 33 checking a making command out of a brake power circuit 26, while calculating state information upon reading out those of storage data of the RAM 35, and diagnosing a state at the present point of time of the brake 27 upon comparing this state information with the initial state information, and a communication part 36 notifying the diagnosed result by the CPU 33 to the outside, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elevator drive system that can be braked by a pressing force of a brake spring, and performs an opening operation by an attractive force of an electromagnetic coil when full-wave rectified power is supplied from a brake power supply circuit. The present invention relates to a diagnostic device used to diagnose a magnet brake for an elevator.

[0002]

2. Description of the Related Art Magnet brakes for elevators are extremely important safety devices for elevators. Therefore, it is necessary to maintain the quality by performing maintenance and inspection for periodically diagnosing whether an abnormality has occurred. As a conventional technique for diagnosing the operation state of the magnet brake, a maintenance worker checks the operation timing of the brake from the operation sound of the amateur, measures the distance between the armature and the electromagnetic coil, and determines these values as a determination value. The work of comparison was common.

[0003]

However, in the conventional brake diagnosis method, measurement results tend to be different due to individual differences of maintenance staff such as whether they are experienced or not, and individual differences of brakes themselves are ignored. Since the diagnosis is performed based on the common judgment value, it is difficult to obtain a highly reliable diagnosis result. Furthermore, since diagnosis work for the magnetic brake is not performed frequently, conventionally, even if the diagnosis result is good at one diagnosis work, a failure is expected to occur at the next scheduled diagnosis work. He had to adjust and replace the brake parts at that point, albeit somewhat premature and uneconomical.

The present invention has been made in view of such problems of the prior art, and an object of the present invention is to always provide a highly reliable diagnosis result so that parts replacement and adjustment work can be performed at an optimum time. An object of the present invention is to provide a diagnostic device for a magnet brake for an elevator.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides an electromagnetic coil which brakes an elevator drive system by a pressing force of a brake spring and which supplies full-wave rectified power from a brake power supply circuit. As a diagnostic device applied to an elevator magnet brake that performs an opening operation with an attractive force, a current detector that detects a braking operation current, and an A / A that converts the braking operation current detected by the current detector into a digital amount. A D converter, a RAM for temporarily storing a current signal output from the A / D converter, a ROM for storing initial state information extracted from the brake operation current when a magnet brake is newly installed, While confirming the power-on command from the power supply circuit, the current signal stored in the RAM is read to calculate state information, and the state information is A CPU for diagnosing the state of the magnetic brake as compared with the initial state information, and configured to include a communication unit for reporting a diagnosis result by the CPU to the outside.

[0006] The diagnostic apparatus thus configured constantly monitors the brake operating current, extracts the current state information calculated from the current signal from the brake operating current when the magnet brake is newly installed, and stores the information. Since the current operation state of the brake is diagnosed in comparison with the state information, whether or not the brake is operating normally, and if it is not normal, where the abnormality occurs and how much the abnormality is Detailed and accurate diagnosis, such as whether or not, can always be performed automatically. Even if the brake has not failed, if it is determined from the diagnosis result that the state is immediately before the failure, an alert can be issued to an elevator maintenance company or the like. This can be performed at the appropriate time, and the failure of the brake can be prevented.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is an explanatory view of an elevator mechanism according to an embodiment of the present invention. Reference numeral 1 denotes a commercial AC power supply, 2 denotes an elevator main body, 3 denotes a brake diagnostic device, and 4 denotes an elevator maintenance company.

First, the mechanism of the elevator main body 2 will be described. The electric motor 21 is driven by the electric power supplied from the electric power converter 20, and the electric motor 21 is driven by a deflecting wheel 22 attached to a rotating shaft (electric motor shaft) 211 of the electric motor 21. Rope 23
Is wound around the rope 23, and a car 24
And a counterweight 25 are suspended. The AC power supplied from the commercial AC power supply 1 is supplied to the brake power supply circuit 26.
Is converted to full-wave rectified power by the brake power supply circuit 2
When the full-wave rectified power is supplied from 6 to the magnet brake 27 via the relay 29, the brake 27 performs an opening operation, and when the relay 29 is opened and the power supply is cut off,
The brake 27 performs a braking operation. The relay 29 is provided with a closing command M of the elevator control circuit 28.
Open and close by G *.

On the other hand, the brake diagnosis device 3 is connected between the magnet brake 27 and the relay 29 and detects a current (brake operation current) flowing from the brake power supply circuit 26 to the brake 27, and a current detector 31 for detecting the current. An A / D converter 32 for converting the brake operation current detected by the current detector 31 into a digital quantity; a current signal (data of the brake operation current) output from the A / D converter 32; By taking in the closing command MG * to be output and performing signal processing, the magnet brake 27
CPU 33 for diagnosing the state of the above, a ROM 34 storing a value (judgment value) serving as a criterion when the CPU 33 makes a diagnosis, and a current signal taken into the CPU 33 via the A / D converter 32. RAM 35 for temporarily storing
And a communication unit 36 for notifying the result of the diagnosis by the CPU 33 to the external elevator maintenance company 4 via a public line. The determination value stored in the ROM 34 is the initial state information of the brake 27 extracted from the brake operation current measured when the magnet brake 27 is newly installed, and is a value set according to each magnetic brake. is there. When the CPU 33 makes a diagnosis, the initial state information is compared with the current data of the brake operating current stored in the RAM 35.

Here, the structure and operation of the magnet brake 27 will be described with reference to FIG.
A disk 270 attached to the outer shell (shaded portion) of the rod 27 is fixed to one end of a rod 271.
1 has a core 272 containing an electromagnetic coil 277.
Has been fixed. The electromagnetic coil 277 is energized when a current (brake operation current) is supplied from the brake power supply circuit 26 to generate an attractive force. A portion for leading the electromagnetic coil 277 to an external device is an enamelled portion. The lead wire 273 is hardly broken even when the wire is thickly covered and bent. When the electromagnetic coil 277 generates an attractive force, the armature 274 is attracted to the core 272 side as shown in FIG.
When no suction force is generated, as shown in FIG. 2 (b), the braking spring 2
It is pressed against the disk 270 with a resilience of 75. Therefore, when the electromagnetic coil 277 is not excited, the lining 276 spline-coupled to the motor shaft 211 is pinched between the armature 274 pressed against the disk 270 by the braking spring 275 and the disk 270. A strong frictional force is generated, and the rotation of the motor shaft 211 is braked by the frictional force. Further, in this braking state, when a current equal to or more than a predetermined value flows through the electromagnetic coil 277 and the attraction force of the coil 277 exceeds the pressing force of the braking spring 275, the armature 274 moves to the core 272 side, so that braking is released (brake release). ) And the motor shaft 2
11 becomes rotatable.

Next, in the initial state at the time when the magnet brake 27 is newly installed, the state of the change in the brake operating current I detected when the brake state changes from the braking state to the released state (non-braking state) and returns to the braking state again. This will be described with reference to FIG. First, a description will be given of a case where the vehicle shifts from the braking state to the releasing state. At the timing shown in FIG.
When a signal for turning on the injection command MG * is output from the elevator control circuit 28, the contact of the relay 29 is closed and full-wave rectified power is supplied from the brake power supply circuit 26, and the brake operating current is supplied to the electromagnetic coil 277 of the magnet brake 27. I flows. Then, the braking operation current I is as shown in FIG.
As shown in (b), the current starts flowing from the timing when the relay 29 is closed, and gradually increases with a time constant determined by the inductance of the electromagnetic coil 277 and the winding resistance value. 277
The suction force that is generated also increases. At this time, the armature 274 is not driven at first because the pressing force of the braking spring 275 is stronger than the attraction force of the electromagnetic coil 277, but the attraction force exceeds the pressing force of the braking spring 275 at a timing. In other words, when the time a ₀ has elapsed since the relay 29 was closed,
As shown in FIG.
7 and moves to the core 272 side, and the magnet brake 27 is released. Further, when the armature 274 moves toward the core 272 in this way, the magnetic flux of the electromagnetic coil 277 changes, so that a disturbance of the magnitude b ₀ occurs in the brake operation current I at the timing. Thereafter, the brake operating current I is increased to a rated value, the current pulse of magnitude c ₀ is generated even if the rated values shown in FIG. 3 (b). This current pulsation is generated by the rectification operation of the brake power supply circuit 26, and its magnitude is proportional to the output voltage of the brake power supply circuit 26, and the pulsation frequency is the frequency f _{0 of the} commercial AC power supply 1.
Becomes

A case where the magnet brake 27 shifts from the released state to the braking state will be described. When a signal for turning off the closing command MG * is output from the elevator control circuit 28 at the timing shown in FIG.
Although the contact of the relay 29 is opened and the power supply to the magnet brake 27 is cut off, the brake operation current I does not immediately become zero due to the inductance of the electromagnetic coil 277. Therefore, even after the timing, at first, the attraction force of the electromagnetic coil 277 is larger than the pressing force of the braking spring 275, and the armature 274 remains in the state of being attracted to the core 272 side. However, when the attractive force of the electromagnetic coil 277 becomes smaller than the pressing force of the braking spring 275 at the timing, the armature 274 is pressed by the braking spring 275 and moves toward the disk 270 as shown in FIG. Magnet brake 27
Is in a braking state in which the pinched lining 276 regulates the rotation of the motor shaft 211. Further, when the armature 274 moves to the disk 270 side, the magnetic flux of the electromagnetic coil 277 changes, so that the braking operation current I is disturbed by the magnitude d ₀ at a timing, and thereafter, the braking operation current I decreases. Becomes zero.

FIG. 4 is a characteristic diagram showing the result of frequency analysis of the waveform of the brake operation current I shown in FIG. 3B. In the initial state when the magnet brake 27 is newly installed, the frequency of the brake operation current I The components are the DC component and
And the frequency f ₀ of the current pulse of magnitude c ₀ is dominant.

Next, how the waveform of the brake operating current I changes when various abnormalities occur in the magnet brake 27 will be described with reference to FIGS.

FIG. 5 is a characteristic diagram showing a waveform of the braking operation current I when the lining 276 is worn, in comparison with a normal waveform (broken line). That is, the lining 27
When the wear amount of the magnet 6 increases, the distance between the armature 274 and the electromagnetic coil 277 of the magnet brake 27 increases in the braking state shown in FIG. However, as this distance increases, the attractive force of the electromagnetic coil 277 acting on the armature 274 decreases. Therefore, when the lining 276 is worn when the magnet brake 27 is in the braking state, the armature 274 is attached to the core 2 unless the electromagnetic coil 277 generates a larger attractive force than in the normal state.
It cannot be moved to the 72 side, so amateur 2
The brake operation current I when the 74 is driven to be sucked becomes larger than that in the normal state, and the time required for driving the armature 274 becomes a value a ′ longer than the value a _{0 in the} normal state.

FIG. 6 is a characteristic diagram showing the waveform of the armature stroke and the braking operation current I when the armature 274 is in a hard state, as compared with a normal time (broken line). In other words, if the amateur 274 gets stuck,
Amateur stroke is smaller than normal,
It becomes smaller disturbance of the braking operation current I occurs in the inductance change due to movement of the armature 274, in the figure, when it solid astringency is b ₀ to disturbance during normal current occurs when the armature 274 is driven aspirated b '
The disturbance of the current that occurs when the armature 274 is driven to be pushed is d ₀ in a normal state, but decreases to d ′ in a tight state.

FIG. 7 is a characteristic diagram showing a waveform of the brake operating current I when an abnormality occurs in the output voltage of the brake power supply circuit 26, as compared with a normal operation (broken line). That is,
If any abnormality occurs in the output voltage, the current pulsation changes to a magnitude c ′ different from the magnitude c ₀ at normal time.

FIG. 8 is a characteristic diagram showing a waveform of the braking operation current I when chattering occurs at the contact point of the relay 29 and a frequency analysis result thereof. That is, the relay 29
When chattering occurs at the contact point of FIG.
As shown in FIG. 8B, a current pulsation (frequency f ′) having a higher frequency than the current pulsation (frequency f ₀ ) caused by the brake power supply circuit 26 occurs, and the frequency analysis result of the brake operation current I is shown in FIG. ), It is different from the normal state (broken line).

As described above, when various abnormalities occur in the magnet brake 27, a characteristic change appears in the waveform of the brake operating current I according to the content and degree of the abnormalities. Therefore, based on these contents, the flow of the diagnosis operation of the magnet brake 27 by the diagnosis device 3 will be described with reference to the flowchart of FIG.

First, the CPU 33 controls the elevator control circuit 2
8 confirms whether or not the turning-on command MG * has been turned on (step 100). At the same time as the turning-on command MG * is generated, the brake operating current I ′ detected by the current detector 31 is detected by the A / D converter 32. A / D converted (step 200),
The signal relating to the brake operation current I 'is temporarily stored in the RAM 35 (step 300). Then the CPU
33 checks whether or not the closing command MG * has been turned off (step 400) and whether or not the brake operating current I 'has become zero (step 500). When it is confirmed that the brake operation current I ′ is zero, it is determined that the opening operation of the magnet brake 27 has been completed, and the process proceeds to the following diagnostic processing.

In the diagnosis process, first, the CPU 3
3 reads out a signal relating to the brake operation current I ′ temporarily stored in the RAM 35 (step 600), and responds to the current signal from steps 700 to 1000
By performing the digital signal processing described above, various information a ′ regarding the current state of the magnet brake 27 is obtained.
Ｆf ′ are calculated.

That is, in step 700, the time a ′ is calculated as information reflecting the abrasion state of the lining 276, and in step 800, the magnitude b ′ of the turbulence of the current and the information reflecting the congestion state of the amateur 274 are calculated. d ′ is calculated. In step 900, the magnitude of the current pulsation c 'is calculated as information reflecting the abnormality of the output voltage of the brake power supply circuit 26. In step 1000,
The frequency f ′ based on the frequency analysis result is calculated as information reflecting the chattering state of the contact of the relay 29. Then, the CPU 33 stores these calculation results in the RAM 35.

Next, the CPU 33 reads out the initial state information stored in the ROM 34 in advance as a judgment value at the time of diagnosis (step 1100). The initial state information is a value extracted from the brake operation current when the magnet brake 27 is newly installed, and includes the time a ₀ , the magnitudes of the current disturbances b ₀ and d ₀ , and the magnitude of the current pulsation c _0. , Frequency f ₀ based on frequency analysis, and the like.

Thereafter, the CPU 33 determines the current state information a 'to f' of the magnet brake 27 and the judgment values a _{0 to} f _0.
And for each information, the difference Δa ~
Δf is calculated (step 1200).

Next, the CPU 33 reads a diagnostic table as shown in FIG. 10 stored in the ROM 34 in advance (step 1300), and compares Δa to Δf with the respective diagnostic tables as shown in steps 1400 to 1700. Thereby, the current degree of abnormality of each part of the magnet brake 27 is clarified.

For example, the diagnosis table shown in FIG. 10A is for diagnosing the abrasion state of the lining 276 (step 1400).
If greater than a ₁ is, CPU33 is, make a diagnosis of the braking force of the magnet brake 27 is there is a possibility that interfere with the operation of the elevator is a shortage. Similarly, the diagnosis table shown in FIG. 10B is for diagnosing the tight state of the amateur 274 (step 150).
0) If the current value of Δb is larger than the threshold value Δb ₁ , it is diagnosed that unacceptable hard traffic has occurred. The diagnosis table shown in FIG. 10C is for diagnosing the state of the output voltage of the brake power supply circuit 26 (step 1600), and is used when the current value of Δc is larger than the threshold value Δc _1. Is diagnosed that an unacceptable voltage abnormality has occurred. Also, the CPU 33
Compares the Δf calculated by frequency analysis of the brake operation current with a diagnosis table (not shown) to check whether or not high-frequency current pulsation due to chattering has occurred, and diagnoses chattering at the contact point of the relay 29 ( Step 1700).

When the current degree of abnormality of each part of the magnet brake 27 is diagnosed, the CPU 33 notifies the diagnosis result to the elevator maintenance company 4 connected via a public line (step 1800).

As described above, the diagnostic apparatus described above detects the brake operating current of the magnet brake 27 during normal operation of the elevator, extracts the current state information of the brake 27, and uses this information as the initial state information at the time of new installation. Since the abnormality degree of each part of the brake 27 is diagnosed as compared with the above, it is possible to avoid measurement errors due to individual differences of maintenance personnel and erroneous diagnosis due to individual differences of the brake itself, and it is easy to obtain a highly reliable diagnosis result. ing. Further, since this diagnostic device can constantly monitor the operation state of the magnet brake 27 and detect and issue that the brake 27 is in a state immediately before the failure,
Brake failure can be prevented beforehand, and parts replacement and adjustment work can be performed at the optimal time, thereby reducing maintenance costs.

[0029]

The diagnostic apparatus for an elevator magnet brake according to the present invention is embodied in the form described above and has the following effects.

Since a measurement error due to individual differences of maintenance personnel and an erroneous diagnosis due to individual differences of the brake itself can be avoided, a highly reliable diagnosis result is always obtained.

Further, since the operation state of the brake is constantly monitored, and it is possible to detect and notify that the brake has become a state immediately before the failure, the brake failure can be reliably and efficiently prevented.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a mechanism of an elevator according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing the structure and operation of a magnet brake.

FIG. 3 is a characteristic diagram showing a waveform and the like of a brake operation current in an initial state of the magnet brake.

FIG. 4 is a characteristic diagram showing a frequency analysis result of a brake operation current in an initial state of the magnet brake.

FIG. 5 is a characteristic diagram showing a waveform of a brake operation current when the lining is worn, as compared with a normal operation.

FIG. 6 is a characteristic diagram showing the waveforms of an amateur stroke and a brake operation current when an amateur gets stuck, as compared with a normal operation.

FIG. 7 is a characteristic diagram showing a waveform of a brake operation current when an abnormality occurs in the output voltage of the brake power supply circuit, as compared with a normal operation.

FIG. 8 is a characteristic diagram showing a waveform of a brake operation current when chattering occurs at a contact point of a relay and a frequency analysis result thereof.

FIG. 9 is a flowchart showing a flow of diagnosis of a magnet brake in the embodiment.

FIG. 10 is an explanatory diagram of a diagnosis table used at the time of diagnosis in the present embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Commercial AC power supply 2 Elevator main body part 3 Diagnostic device 4 Elevator maintenance company 21 Electric motor 22 Deflection car 23 Rope 24 Riding car 25 Counterweight 26 Brake power supply circuit 27 Magnet brake 28 Elevator control circuit 29 Relay 31 Current detector 32 A / D conversion Unit 33 CPU 34 ROM 35 RAM 36 Communication unit 211 Motor shaft 270 Disk 274 Amateur 275 Braking spring 276 Lining 277 Electromagnetic coil

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Masamitsu Yakimaki 1-6-6 Kandanishikicho, Chiyoda-ku, Tokyo Inside Hitachi Building Systems Co., Ltd.

Claims (1)

[Claims] 1. A full-wave rectified electric power from a brake power supply circuit via a relay that can be braked by applying a pressing force of a braking spring to an elevator drive system and that opens and closes in response to a turn-on command of an elevator control circuit. Is supplied, a brake operation current flows, and a diagnostic device for diagnosing an elevator magnet brake capable of releasing the pressing force against the drive system by an attractive force of an electromagnetic coil that excites and excites the brake operation current. A current detector for detecting, an A / D converter for converting a brake operation current detected by the current detector into a digital amount, and a RAM for temporarily storing a current signal output from the A / D converter ,
A ROM that stores initial state information extracted from the brake operation current when a magnetic brake is newly installed,
A CPU for checking the input command, reading the current signal stored in the RAM to calculate state information, and comparing the state information with the initial state information to diagnose a state of a magnet brake; And a communication means for notifying a diagnosis result by the outside to the outside.