JP2002265161A - Diagnostic method for magnet brake - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a diagnostic method for a magnet brake capable of providing a highly reliable diagnostic result in a short time. SOLUTION: In step S1, an elevator is stopped on a random floor or in a random position. Torque is applied to cores 16 and 17 receiving affects of sticking by a torque wrench attached to a push rod 19. Rotational torque of when the cores 16 and 17 start moving is measured. An anomaly is diagnosed by comparing a rotational torque measurement value with a preset determination value. Even when there is no sticking, sticking occurrence timing and overhaul timing are forecasted from the rotational torque measurement value.

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 a magnet brake that releases a braking force by exciting an electromagnetic coil.

[0002]

2. Description of the Related Art In general, a magnet brake 2 used as a braking device for an electric motor for an elevator is mounted on a machine beam 3 installed on a floor as shown in the front and side views of FIGS. The rotating shaft 4 of the electric motor 1 is connected to a traction machine 6 fixed on the machine beam 3 via a rotating drum 5. A pair of braking arms 7, 8 are arranged so as to sandwich the outer peripheral portion of the brake drum 5, and both braking arms 7, 8 are rotatably supported by the machine beam 3 by pins 9, 10 provided at the lower ends, respectively. Brake shoes 11 and 12 are fixed to opposed portions of the intermediate portion, respectively. A rod 13 penetrates through the upper ends of both braking arms 7 and 8 and is elastically compressed by a compression spring 14 attached to the rod 13 so as to sandwich the upper ends of the braking arms 7 and 8. It is energizing. Therefore, in the steady state, the brake
A compression spring 14 applies a pressing force to the brake drum 5 to generate a braking force on the brake drum 5, and the braking force is adjusted by changing a tightening allowance of the compression spring 14 on the rod 13. can do.

FIG. 4 is a sectional view showing the inside of a magnet case 15 of the magnet brake 2 shown in FIG. An electromagnetic coil 1 is provided on the outer peripheral surface of the hollow cylindrical magnet case 15.
A core 16 and a core 17 are arranged inside the electromagnetic coil 18 with a gap such that the inner peripheral surface of the magnet case 15 and the outer surface thereof are substantially parallel to each other. , 17 are arranged opposite to each other in the coaxial direction. A push rod 19 attached to the center of the core 17 on the opposite side is movably inserted into a hole passing through the core 16 in the axial direction. A push rod 20 attached to the opposite side of the core 16 is movably inserted. A receiving member 21 is attached to the distal end of the push rod 20, and the distal end of the push rod 19 and the receiving member 21 of the push rod 20 are in contact with the pressing rods 22, 23 attached to the braking arms 7, 8, respectively. In a steady state, the core 16 and the core 17 are pressed by the compression spring 14 and are held at the non-excited position. When the electromagnetic coil 18 is excited, the core 16 is displaced in the axial direction indicated by the arrow A1.
Are configured to be displaced in the axial direction indicated by arrow A2 when the electromagnetic coil 18 is excited.
In response to the displacement, the pair of braking arms 7 and 8 shown in FIG. 3 are pressed in opposite directions to release the brake shoes 11 and 12 from the brake drum 5 and release the braking force by the compression spring 14. I have.

The elevator magnet brake 2 is an extremely important safety device for an elevator, and periodically diagnoses whether an abnormality has occurred.
It is necessary to strive to maintain quality. For example, in the gap between the magnet case 15 and the cores 16 and 17, a mixture of dust and lubricating oil accumulates over time.
This prevents the cores 16 and 17 from returning to the positions shown in FIG. 4 even if the cores 16 and 17 are not excited. When this congestion condition occurs, the brake shoes 11 and 12 always keep the brake drum 5
As a result, the elevator car free-runs without brakes, causing a serious accident. Therefore, it is necessary to periodically disassemble the magnet brake to periodically diagnose whether or not an abnormality has occurred, and to remove the mixed mixture.

As a conventional diagnostic device for diagnosing the operating state of such a magnetic brake, for example, Japanese Utility Model Application Laid-Open No.
As described in Japanese Patent No. 172829, a display device, a power supply and a variable resistor are connected in series to an elastic body whose electric resistance changes when pressed, and this elastic body is sandwiched between a braking arm and a magnet case. 2. Description of the Related Art A core stroke detecting device is known in which when a gap between a brake arm and a magnet case, that is, a stroke of a core changes, a display device indicates the change. Further, as described in Japanese Utility Model Laid-Open No. 4-115872, the stroke is confirmed during the operation of the elevator by using a ruler established in the magnet case and a pointer fixed on the top surface of the core to indicate the vertical displacement on the ruler. As described above, there is known a method in which the presence or absence of a change in the stroke is numerically recorded at the time of the periodic inspection to perform tracking and monitoring to supplement a slight change in the stroke which is a precursor of the core solid traffic.

[0006]

However, since the conventional magnetic brake diagnostic apparatus substantially detects the stroke of the braking arm, it cannot accurately diagnose the hard state of the core and has high reliability. Difficult to get diagnostic results,
Diagnostic work costs have increased due to the need for expensive detectors. Also, in the method of visually measuring the stroke of the core during the operation of the elevator, it is difficult to accurately detect the stroke, and it is difficult to obtain a highly reliable diagnosis result, and the magnet brake is disassembled based on the unreliable diagnosis result. When the cleaning operation is performed, an extra operation occurs when the cleaning operation is unnecessary.

An object of the present invention is to provide a method of diagnosing a magnetic brake which can obtain a highly reliable diagnosis result in a short time.

[0008]

In order to achieve the above object, the present invention provides an electromagnetic coil mounted on an outer periphery of a magnet case, and an electromagnetic coil disposed on an inner periphery of the magnet case to be displaced by excitation of the electromagnetic coil. A braking arm to which a braking force is applied by a braking spring to generate a braking force on the brake drum,
And a push rod that presses the braking arm in accordance with the displacement of the core to release a braking force on the brake drum by the brake shoe, wherein a rotational force is applied to the push rod. The method is characterized in that a rotational torque when the core starts moving is measured, and the rotational torque measured value is compared with a predetermined judgment value to diagnose an abnormal operation of the core.

According to the method of diagnosing a magnet brake according to the present invention, a rotational torque is measured when applying a rotational force to a core in which an abnormal operation due to heavy traffic appears, and the measured rotational torque is compared with a previously measured determination value. Since the operation abnormality is diagnosed, the operation abnormality of the core can be quantitatively grasped, and a highly reliable diagnosis result can be obtained in a short time.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 2 to 4 are a front view, a side view, and a cross-sectional view of a main part of a magnet brake for an elevator to which the method for diagnosing a magnet brake according to the present invention is applied.

On a machine beam 3 installed on the floor, a magnet brake 2 is fixed adjacent to the electric motor 1, and a rotating shaft 4 of the electric motor 1 is fixed on the machine beam 3 via a rotary drum 5. 6 is connected. A pair of braking arms 7, 8 are arranged so as to sandwich the outer peripheral portion of the brake drum 5, and both braking arms 7, 8 are rotatably supported by the machine beam 3 by pins 9, 10 provided at the lower ends, respectively. Brake shoes 11 and 12 are fixed to opposing portions of the intermediate portion, respectively. A rod 13 penetrates through the upper ends of both braking arms 7, 8, and is elastically attached to the rod 13 by a compression spring 14 so as to sandwich the upper ends of the braking arms 7, 8. It is energizing. Accordingly, in the steady state, a pressing force is applied to the brake drum 5 by the compression spring 14 to the brake shoes 11 and 12 to generate a braking force on the brake drum 5.
4 can be adjusted by changing the tightening allowance.

As shown in FIG. 4, an electromagnetic coil 18 is mounted on the outer peripheral surface of the hollow cylindrical magnet case 15.
The core 16 and the core 17 are arranged with a gap so that the inner peripheral surface of the core 5 and the outer surface thereof are substantially parallel to each other.
Reference numerals 6 and 17 are arranged opposite to each other in the coaxial direction. A push rod 19 attached to the center of the core 17 on the opposite side is movably inserted into a hole passing through the core 16 in the axial direction. Push rod 20 attached to opposite side of core 16
Is movably inserted. A receiving member 21 is attached to the tip of the push rod 20 and the push rod 19
And the receiving member 21 of the push rod 20 are in contact with the pressing rods 22 and 23 attached to the braking arms 7 and 8, respectively, and are pressed by the compression spring 14 in a steady state to de-energize the core 16 and the core 17. Hold in position. When the electromagnetic coil 18 is excited, the core 16 has an arrow A1.
The core 17 is displaced in the axial direction indicated by
Are excited to be displaced in the axial direction indicated by an arrow A2, and the pair of braking arms 7, 8 shown in FIG. 3 are pressed in opposite directions according to the displacement of the cores 16, 17, respectively. , Brake shoes 11 and 12 to brake drum 5
And the braking force by the compression spring 14 is released.

FIG. 1 is a flowchart showing a method of diagnosing a magnetic brake according to one embodiment of the present invention.

The diagnosis of the magnet brake 2 is as follows. First, in step S1, the elevator is stopped at an arbitrary floor or position, and in step S2, the brake shoes 11, 12 brake the rotary drum 5, that is, the cores 16, 17 are released. At this position, a torque wrench is set in the notch at the tip of the push rod 19. Next, in step S3, a force is gradually applied to the torque wrench, and the rotational torque at the moment when the core 17 rotates in the circumferential direction is measured. At this time, when the push rod 19 attached to the core 17 is rotated in the circumferential direction, the push rod 20
Also rotates in the same direction, and the core 16 to which the push rod 20 is connected also rotates in the same direction. In this way core 1
The rotation torque measurement in steps 6 and 17 can be performed in a short time.

In step S2 described above, the brake
1 and 12 brake the rotary drum 5, that is, the core 1
At the position where the buttons 6 and 17 are released, a torque wrench is set at the tip of the push rod 20, and then, at step S3
The force may be gradually applied to the torque wrench. in this case,
The core 16 that rotates the push rod 20 attached to the core 16 in the circumferential direction rotates and the push rod 2
Since the core 17 and the push rod 19 also rotate in the same direction via 0, a measured rotational torque can be obtained even when the rotational torque at the moment when the cores 16 and 17 rotate in the circumferential direction is measured. Therefore, no matter which of the push rods 19, 20 is rotated, the cores 16, 17 rotate simultaneously,
The measured rotational torque is a result of measuring a higher rotational torque of either of the cores 16 and 17.

On the basis of the measured rotational torque, in step S4, it is determined whether or not a heavy traffic has occurred by comparing with a judgment value set in advance in consideration of the safety factor in consideration of the safety factor. If the measured rotational torque value is larger than the determination value, it is determined in step S5 that hard traffic has occurred, and the magnet brake 2 is disassembled and maintained.

On the other hand, if it is determined in step S4 that the measured rotational torque has not reached the determination value of the occurrence of the heavy traffic, the process proceeds to step S
From the relationship between the measured rotational torque value and the running time investigated in this time, the running time from the time of diagnosis to the occurrence of the congestion is calculated from the calculation formula constructed in consideration of the safety factor, and step S
At 7, the travel time is divided by the monthly average travel of the elevator to calculate the number of months until the next overhaul. This allows maintenance work to be performed at the optimal time.

The above-described rotational torque increases in proportion to the amount of the mixture of dust and lubricating oil accumulated in the gap between the magnet case 15 and the cores 16 and 17, so that the rotational torque at which hard traffic occurs is determined in advance. By measuring, the above-described determination value can be appropriately set. Moreover, an experiment was conducted on the rotational torque before and after the displacement of the cores 16 and 17, and it was found that there was no difference between the rotational torque after the displacement after releasing the braking force and the rotational torque before the displacement in the braking state. . Thus, by measuring the rotational torque at the release positions of the cores 16 and 17, it is possible to diagnose the hardness of the cores.

The core 1 of the magnet brake 2 of the actual machine
Investigations were also made on the rotational torques 6, 17 and the elevator running time or core excitation time, and the relationship between the running time and the rotating torque was found. From the relationship between the running time and the running torque, it was possible to construct a calculation formula for calculating the running time from the measured running torque at the time of diagnosis to the occurrence of the heavy traffic. By using this calculation formula, a substantially accurate period until the next disassembly and maintenance can be obtained, and the adjustment work can be performed at an optimal time.

According to such a method of diagnosing the magnet brake, the elevator is stopped at an arbitrary floor or position, and a rotational force is applied to the cores 16 and 17 affected by heavy traffic, so that the cores 16 and 17 start moving. Since the rotational torque is measured, and the measured rotational torque is compared with a predetermined judgment value to diagnose an abnormality, the solidness of the cores 16 and 17 can be quantitatively grasped, and the reliability can be reduced in a short time. A highly diagnostic result can be obtained. In addition, since the time required for the occurrence of the congestion is calculated and predicted based on the measured rotational torque, and the disassembly and cleaning is performed at the predicted time, wasteful work in a time when the congestion does not occur is performed. The maintenance cost can be reduced by eliminating maintenance work, and disassembly and cleaning can be performed at the appropriate time.

FIGS. 5 and 6 are a side view and an enlarged sectional view of a main part of a magnet brake adopting a method of diagnosing a magnet brake according to another embodiment of the present invention.

In the above-described embodiment, the cores 16 and 17
So-called horizontal magnet brake 2 in which is displaced in the horizontal direction
However, here, a so-called vertical magnet brake 2 in which the cores 16 and 17 are vertically displaced is shown, and the same reference numerals are given to the same components as those in the previous embodiment, and detailed description is omitted. .

When the electromagnetic coil 18 is excited, the core 16 is displaced downward in FIG. 6 and is attracted to the core 17, and at this time, the push rod 19 attached to the core 16 is also displaced downward. The displaced push rod 19 is connected to the pressing rods 22, 2 via the levers 24a, 24b shown in FIG.
3 is pushed outward, the brake arms 7, 8 are pushed out against the compression spring 14, and the brake shoes 11, 12 are separated from the brake drum 5.

Also in the magnetic brake having such a structure, the elevator is stopped at an arbitrary position in step S1 shown in FIG. 1 as in the previous embodiment, and the elevator is stopped at the tip end of the push rod 19 in step S2. A torque wrench is set, and in step S3, a rotational force is gradually applied to the push rod 19 to measure a rotational torque at the moment when the core 16 rotates, and based on the measured rotational torque, a step S3 in FIG.
If the processing proceeds in accordance with the procedure from step 4
6, 17 can be quantitatively grasped, and a highly reliable diagnosis result can be obtained in a short time. In addition, the time until solid congestion occurs is calculated and predicted based on the measured rotational torque, and the cleaning and disassembly maintenance is performed at the predicted time. Eliminating the operation also saves the maintenance staff's operation cost, and the disassembly and cleaning can be performed at an appropriate time.

[0026]

As described above, the method of diagnosing a magnet brake according to the present invention measures the rotational torque at the time of starting to move by applying a rotational force to a core in which an abnormal operation due to heavy traffic or the like appears. Since the abnormality is diagnosed by comparing with the set determination value, the operation abnormality of the core can be quantitatively grasped, and a highly reliable diagnosis result can be obtained in a short time.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a method of diagnosing a magnetic brake according to an embodiment of the present invention.

FIG. 2 is a front view showing an elevator magnet brake adopting the magnet brake diagnosis method shown in FIG. 1;

FIG. 3 is a side view of the elevator magnet brake shown in FIG. 2;

FIG. 4 is an enlarged sectional view of a main part showing a released state of the elevator magnet brake shown in FIG. 2;

FIG. 5 is a front view showing another elevator magnet brake employing the magnet brake diagnosis method shown in FIG. 1;

6 is an enlarged sectional view of a main part showing a released state of the elevator magnet brake shown in FIG. 5;

[Explanation of symbols]

 2 Magnet brake 5 Brake drum 7, 8 Braking arm 11, 12 Brake shoe 13 Rod 14 Compression spring 15 Magnet case 16, 17 Core 18 Electromagnetic coil 19, 20 Push rod 22, 23 Press rod

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Jun Taguchi 1-25-1, Nishi-Shinjuku, Shinjuku-ku, Tokyo F-term 3F304 BA07 BA13 EA29

Claims (2)

[Claims] An electromagnetic coil mounted on an outer periphery of a magnet case, a core disposed on an inner periphery of the magnet case and displaced by excitation of the electromagnetic coil, and a pressing force applied by a braking spring. A brake arm mounted with a brake shoe that generates a braking force on the brake drum, and a push rod that presses the brake arm in accordance with the displacement of the core to release the braking force on the brake drum by the brake shoe. In the method of diagnosing the magnetic brake, the rotational torque when the core starts to move by applying a rotational force to the push rod is measured, and the measured rotational torque is compared with a predetermined judgment value to determine whether the core has malfunctioned. A method for diagnosing a magnetic brake, characterized in that a diagnosis is made. 2. The apparatus according to claim 1, wherein when the measured rotational torque of the core has not reached the determined value, the magnet brake is not disassembled and maintained, and an abnormality is generated from the measured rotational torque. A method for diagnosing a magnetic brake, comprising calculating a time until a maintenance is performed and determining a next maintenance time.