JP6625497B2 - Abnormality diagnosis device and abnormality diagnosis method for elevator brake - Google Patents

Description

  The present invention relates to an abnormality diagnosis device and an abnormality diagnosis method for detecting an abnormality of a lift brake.

  Electromagnetic brakes are generally used as elevator brakes. In this brake device, the brake shoe is pressed against the brake drum or brake disc, which is a rotating body that rotates with the sheave, by the elastic force of the brake spring, and the friction force between the brake drum or brake disc and the brake lining fixed to the brake shoe is applied. This prevents the sheave from rotating. As a result, the car is braked. To release the braking force, the brake lining is released from the brake drum or the brake disc by releasing the pressing of the brake shoe against the elastic force of the brake spring by the electromagnetic force generated by the brake core. At this time, the main role of the elevator brake is to keep the car stopped when the electric motor of the hoist is stopped.

  If a malfunction occurs in the brake operation as described above, the braking force is not sufficiently released, and the car cannot be moved up and down normally. Therefore, as a conventional technique for detecting an abnormality of a lift brake, a technique described in Patent Document 1 is known. In this conventional technique, the average value of the torque command value of the motor from one start to stop of the car is calculated, and the unbalanced torque caused by the difference between the weight of the car and the weight of the counterweight during the stop of the car is calculated. Is calculated. Further, the friction torque is calculated by subtracting the unbalanced torque from the average value of the torque command values. When the friction torque becomes equal to or more than a predetermined value, it is determined that the brake is dragged (the car is running with the brake applied).

Japanese Patent No. 3244643

  According to the above prior art, it is possible to detect an abnormality of the elevator brake with high accuracy based on the frictional force of the brake. However, there is a problem that an erroneous notification of an abnormal alert (report in a normal state) occurs as the number of passengers in the car increases or decreases.

  Accordingly, the present invention provides a highly reliable apparatus and method for diagnosing a brake abnormality for an elevator, which is capable of detecting a brake abnormality stably and with high accuracy while suppressing occurrence of false alarms.

In order to solve the above-mentioned problems, an apparatus for diagnosing abnormality of an elevator brake according to the present invention includes a brake state in which rotation of the sheave is prevented by frictional force between a rotating body connected to a sheave driven by an electric motor and a brake lining. Diagnosis, is to send an alarm when an abnormality is detected in the brake, a load sensor that measures the load in the car, and a control unit that creates a torque command value for controlling the electric motor, Surplus torque calculating means for calculating surplus torque from the load measured by the load sensor and a torque command value created by the control means, and friction force calculating means for calculating a friction force from the surplus torque calculated by the surplus torque calculating means An eccentric load detecting means for detecting an eccentric load in the car, a frictional force calculated by the frictional force calculating means, and an eccentric load detecting means. Based on the offset load to be detected, e Preparations and abnormal frictional force determination means for determining the presence or absence of the brake abnormality, an abnormality frictional force determining means, the friction force is equal to or greater than the predetermined reference value, and If there is an eccentric load in the car, it is determined that there is no abnormality in the brake .

According to another aspect of the present invention, there is provided a brake abnormality diagnosis method for an elevator, wherein the brake for preventing rotation of the sheave by frictional force between a rotating body connected to a sheave driven by an electric motor and a brake lining. The first step of diagnosing the state of the brake, sending an abnormality alert when an abnormality is detected in the brake, calculating the excess torque from the load in the car and the torque command value of the electric motor, and calculating the frictional force from the excess torque a second step of calculating, see containing a third step of determining whether the brake abnormality, the based on the eccentric load in the second frictional force and the car calculated in step, a third step In the case where the value of the frictional force is equal to or more than the predetermined reference value and there is an eccentric load in the car, it is determined that there is no abnormality in the brake, and the value of the frictional force is equal to or more than the predetermined reference value. And it determines that when offset load is not in the car, the abnormality is in the brake.

  According to the present invention, the presence / absence of an abnormality in the brake is determined based on the frictional force and the offset load, so that the erroneous notification of the occurrence of the abnormality is suppressed, and the reliability of the abnormality diagnosis is improved.

  Problems, configurations, and effects other than those described above will be apparent from the following description of the embodiments.

1 is a functional block diagram of an abnormality diagnosis device according to an embodiment of the present invention. 1 shows an example of an elevator brake to be subjected to abnormality diagnosis. It is a flowchart which shows the flow of the abnormality diagnosis processing in this embodiment. It is explanatory drawing of the offset load detection means in this embodiment. It is explanatory drawing of the offset load detection means in this embodiment.

  In the embodiment of the present invention, if the frictional force of the brake exceeds a predetermined value, it is determined whether or not the brake is abnormal according to the load distribution by the passengers in the car. Such means is based on the result of the present inventor's examination regarding the false notification of the abnormal alarm in the abnormality diagnosis of the elevator brake.

  According to the study of the present inventor, the main cause of the misinformation is the load distribution by the passengers in the car. That is, if there is a bias in the load distribution in the car, the load detection error increases, and the accuracy of the calculated value of the unbalanced torque caused by the difference between the weight of the car and the weight of the counterweight decreases. As a result, the accuracy of the calculated value of the frictional force of the brake decreases, and an erroneous report occurs.

  On the other hand, in one embodiment of the present invention described later, when the frictional force of the brake exceeds a predetermined value, the presence or absence of the abnormality of the brake is determined according to the presence or absence of the eccentric load by the passenger in the car. That is, if there is no offset load, it is determined that there is an abnormality, and an abnormal alert is transmitted. If there is an offset load, it is determined that there is no abnormality, and no abnormal alert is issued.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each of the drawings, components having the same reference number indicate the same components or components having similar functions.

  FIG. 1 is a functional block diagram of an abnormality diagnosis device for an elevator brake according to an embodiment of the present invention. In the present embodiment, an arithmetic processing device such as a microcomputer functions as each unit in FIG. 1 by executing a predetermined computer program. The computer program is stored in a storage device (not shown) (such as a hard disk or a semiconductor memory).

  As shown in FIG. 1, in an elevator equipped with a brake to be diagnosed, a car 9 and a counterweight are attached to one end and the other end of a main rope wound around a sheave 8 that is rotationally driven by the electric motor 1, respectively. 10 is connected. When the sheave 8 rotates and the main rope is driven, the car 9 and the counterweight 10 move up and down in a hoistway (not shown) in directions opposite to each other. When the car 9 stops on an arbitrary floor, the power supply to the electric motor is stopped, and the rotation of the sheave 8 is prevented by the brake described later, and the stopped state of the car 9 is maintained.

  In the abnormality diagnosis device shown in FIG. 1, the load calculating means 2 calculates the load in the car 9 based on an output signal of a load detector 11 (for example, a load cell) provided in the car 9. Note that the load calculating means 2 calculates the loaded load when the car 9 is stopped, when the passengers get on and off, for example, between when the car door is closed and when the brake is released, and the calculated value is calculated. Remember. Alternatively, the load calculating means 2 calculates the load and stores the calculated value between the time when the car 9 starts running and the time when the car 9 stops next. In this case, the increase or decrease of the load due to the inertial force acting on the traveling car 9 is corrected. In addition, if the load is measured at the time of traveling at a constant speed where the inertial force does not act, it is not necessary to correct the inertial force.

  When the car is running with the brake released, the torque / current control means 3 calculates the torque command value of the electric motor 1 so that the speed of the electric motor 1 matches the speed command value given from a control device (not shown). Then, a current command value corresponding to the torque command value is calculated. The electric motor 1 is controlled so that the current flowing through the electric motor 1 matches the current command value calculated by the torque / current control means 3.

  The surplus torque calculating means 4 holds the unbalanced weight resulting from the difference between the load in the car 9 and the weight of the counterweight 10 based on the loaded load in the car 9 calculated and stored by the load calculating means 2. Is calculated and stored. The weight of the counterweight 10 is stored in advance in a storage device (not shown) (for example, a semiconductor memory). The surplus torque calculation means 4 calculates a difference between the value of the unbalanced torque calculated and stored by the self-means and the torque command value calculated by the torque / current control means 3, that is, a surplus torque.

  The frictional force calculation means 5 calculates the frictional force of the brake based on the surplus torque calculated by the surplus torque calculation means 4. Here, the frictional force calculating means 5 calculates the frictional force from the surplus torque and the diameter of the brake (diameter of the brake drum or brake disk), for example.

  The unbalanced load detecting means 6 detects a load distribution in the car by the passenger based on an image in the car acquired by a camera (not shown) installed in the car, and performs an unbalanced load based on the detected load distribution. Is determined.

  The abnormal frictional force determining means 7 determines whether or not the frictional force calculated by the frictional force calculating means 5 is equal to or more than a predetermined reference value for abnormality determination. When it is determined that the frictional force is equal to or greater than the reference value, the abnormal friction determination unit 7 determines whether there is an abnormality in the brake according to the determination result regarding the presence or absence of the eccentric load by the eccentric load detection unit 6. That is, the abnormal friction determination means 7 determines that there is no brake abnormality when the determination result of the uneven load detection means 6 indicates that there is an uneven load. The abnormal friction determining means 7 determines that the brake is abnormal when the result of the determination by the unbalanced load detecting means 6 indicates that there is no unbalanced load.

  The result of the determination that there is a brake abnormality by the abnormal friction determination means 7 is transmitted to the outside, for example, to a monitoring center, as an abnormality report.

  FIG. 2 shows an example of an elevator brake to be subjected to abnormality diagnosis in the present embodiment. This drawing shows a part of the structure of the brake.

  The brake drum 303, which is a rotating body, forms a hoisting machine together with a sheave and an electric motor (not shown). The brake drum 303 has a cylindrical shape, is coaxially connected to the sheave and the electric motor, and rotates and stops together with the sheave and the electric motor.

  When the car 9 stops the hoisting machine and the car stops, energization of the electromagnet provided in the brake core 301 is stopped, and the suction of the brake armature 307 by the brake core 301 is released. Therefore, the brake armature 307 is urged by the brake spring 302 and moves toward the inner wall of the brake drum 303. Accordingly, the brake shoe 305 connected to the brake armature 307 is pressed against the inner wall of the brake drum 303 while being guided by the brake guide 306 located between the inner wall of the brake drum 303 and the brake armature 302 in the brake drum 303. . At this time, since the brake lining 304 (friction material) of the brake shoe 305 comes into contact with the inner wall of the brake drum 303, the rotation of the brake drum 303 is prevented by the frictional force acting between the brake lining 304 and the brake drum 303. . Thereby, the rotation of the sheave is prevented, and the stopped state of the car 9 is maintained.

  The brake components other than the brake drum 303, which is a rotating body, are supported by a frame (not shown).

  When the car 9 travels, the electromagnet of the brake core 301 is energized, so that the brake armature 307 is sucked by the brake core 301. Therefore, the brake armature 307 moves toward the brake core 301 against the spring force of the brake spring 302. Therefore, the brake shoe 305 is separated from the inner wall of the brake drum 303 while being guided by the brake guide 306. Therefore, the contact between the brake lining 304 and the inner wall of the brake drum 303 is released, and the brake drum 303 is in a rotatable state.

Here, if an abnormality occurs in the brake due to aging of the brake parts or the like, the car 9 runs without sufficiently releasing the contact between the brake lining 304 and the inner wall of the brake drum 303. Therefore, the electric motor 1 is driven while a frictional force acts between the brake lining 304 and the brake drum 303, and the load on the electric motor is increased by the frictional force. Therefore, the abnormality of the brake can be detected based on the torque command value of the electric motor 1. Next, the abnormality diagnosis processing in the abnormality diagnosis device for the elevator brake according to the present embodiment will be described.

  FIG. 3 is a flowchart illustrating the flow of the abnormality diagnosis processing of the elevator brake according to the present embodiment.

  When the process is started (step S101), the brake is released, and the electric motor 1 is controlled by the torque / current control means 3 to drive the hoist (step S102). Thereby, the stopped car 1 starts running.

  Next, the value of the loaded load in the car 9 is detected by the load calculating means 2 (step S103). As described above, the value of the loaded load in the car 9 may be detected before the car 9 travels. In this case, step S103 is performed before step S102.

  Next, the surplus torque is calculated by the surplus torque calculating means 4 (step S104). In step S104, the unbalanced torque is calculated from the value of the load detected in step S103 and the weight value of the counterweight. Further, a difference between the unbalanced torque and a torque command value obtained from the torque / current control unit 3, that is, a surplus torque is calculated.

  Next, based on the surplus torque calculated in step S104, the frictional force calculating means 5 calculates the frictional force of the brake (step S105).

  Next, the value of the frictional force calculated in step S105 is compared with a reference value of a predetermined frictional force serving as a reference for determining the presence or absence of an abnormality in the brake. It is determined whether the calculated frictional force is an abnormal frictional force (step S106). When it is determined that the calculated frictional force is equal to or larger than the reference value and is abnormal (step S106, YES), step S107 is executed next. If it is determined that the calculated frictional force is smaller than the reference value and is not abnormal, that is, normal (step S106, NO), the abnormality diagnosis process ends (step S110).

  In step S107, the eccentric load detecting means 6 calculates the eccentric load in the car. In this embodiment, as described above, the offset load is calculated based on the image in the car.

  After execution of step S107, based on the offset load calculated in step S107, the abnormal frictional force determination means 7 determines whether there is an offset load that affects the detected value of the loaded load (step S107). S108). If it is determined that there is such an eccentric load (step S108, YES), the abnormality diagnosis processing ends (step S110). In this case, since the detection error of the loaded load in step 103 is excessive due to the unbalanced load, it is determined that the calculated frictional force indicates an abnormal value although it is actually normal, and an abnormal The abnormality processing ends without performing the notification. As a result, it is possible to prevent an erroneous alert from being issued.

  In step S107, when the abnormal frictional force determination means 7 determines that there is no offset load that affects the detection value of the loaded load (step S108, NO), next, step S109 is executed.

  In step S109, the abnormal frictional force determination means 7 determines that there is no offset load, that is, that the abnormal value of the frictional force is due to a brake abnormality. In response to such a determination result, an abnormal notification is transmitted to notify that there is a sign of a failure in the brake. After the execution of step S109, the abnormality diagnosis processing ends (step S110).

  Next, detection of an eccentric load in the present embodiment will be described.

  FIG. 4 and FIG. 5 are explanatory diagrams of the eccentric load detecting means in the present embodiment. FIG. 4 and FIG. 5 both show the loading state of the passenger 203 in the car 9.

  As shown in FIGS. 4 and 5, the car 9 is supported by the car frame 50 via a plurality of elastic members for vibration isolation 204, for example, rubber and rubber springs. In such a configuration, if there is a bias in the distribution of passengers in the car 9, an offset load occurs. Therefore, in the present embodiment, the presence or absence of an eccentric load is determined based on the distribution of the passengers calculated using the image of the passengers in the car 9 as follows.

  In the present embodiment, as shown in FIGS. 4 and 5, an image in the car 9 is acquired by a camera 202 provided in the car 9. The camera 202 is installed at a position such that a passenger located at an arbitrary position in the car 9 falls within the field of view of the camera 202. For example, the camera 202 is installed on a car ceiling and photographs the inside of the car 9 including the entire car floor. By performing image processing on an image acquired by the camera 202, the distribution of passengers in the car 9 is calculated. In the image processing, a well-known technique of comparing an image when there is no passenger previously acquired by the camera 202 with an image acquired to detect the passenger is applied.

  In this embodiment, only one camera 202 is used, but a plurality of cameras 202 may be used. In addition, as the camera 202, a normal single-lens camera may be used, or a stereo camera may be used.

  Also, articles loaded in the car, such as luggage carried by the passenger, may be regarded as passengers, and the number of passengers may be calculated. This improves the accuracy of the determination of the presence or absence of an eccentric load.

  In the present embodiment, the distribution of passengers is represented by the position and the number of passengers. Based on the distribution of the passengers, the presence or absence of the unbalanced load is determined. For example, the pattern of the passenger distribution when an eccentric load occurs is stored in the storage device in advance, and if the calculated occupant distribution pattern matches or is close to the stored pattern, it is determined that the eccentric load has occurred. Is determined. Note that a passenger density distribution may be calculated as the passenger distribution.

  In FIG. 4, a plurality of passengers 203 are dispersedly located in the car 9. Therefore, it is determined that there is no large deviation in the distribution of the passengers 203 in the car 9 and there is no deviation load.

  In FIG. 5, a plurality of passengers 203 are locally concentrated in the car 9. Therefore, it is determined that the distribution of the passengers 203 in the car 9 has a large bias, and that there is a bias load.

  Although not shown, the distribution of the passengers in the present embodiment is a two-dimensional distribution with respect to the car floor. In this case, a small number of areas, for example, the car floor is divided into two areas having the same area, and the number of passengers or the density of the passengers in each area is compared. It can be determined that there is. This makes it possible to determine the presence or absence of an eccentric load without increasing the load on the processing unit.

  Considering that the car floor is two-dimensional, for example, the car 9 is divided into two areas in the width direction of a door (not shown) of the car 9 and the number of passengers in each area is compared. It is preferable to divide into two areas in the depth width direction and compare the number of passengers in each area. By using both of these two comparison results, for example, if one of the comparison results indicates an eccentric load, it is determined that there is an eccentric load.

  It should be noted that the loading load by the passenger detected based on the load data detected by the load detector 11 and the loading load estimated based on the number of passengers detected based on the image in the car (= number of people × beforehand) (The average weight per passenger) which is set, and if the difference between the two is equal to or greater than a predetermined value, it may be determined that there is an eccentric load.

  According to the above-described embodiment, when an abnormality is detected in the frictional force of the brake, the presence or absence of an eccentric load is determined, and when it is determined that there is no eccentric load, an abnormality notification is transmitted. As a result, erroneous notification of abnormal notification is suppressed. Therefore, the reliability of the abnormality diagnosis is improved.

  In the present embodiment, the frictional force is calculated from the difference between the calculated value of the unbalanced torque and the torque command value for controlling the electric motor, that is, the surplus torque. Accordingly, if the reference value of the brake frictional force is set irrespective of the weight of the car, the abnormality of the brake can be detected with high accuracy.

  In addition, the presence or absence of an eccentric load can be detected by a plurality of load cells, but if only one camera is used as in the present embodiment, the number of parts of the elevator device due to the provision of the brake abnormality diagnosis device is reduced. The increase can be suppressed. In particular, if the camera for monitoring the inside of the car is also used for the abnormality diagnosis device for the brake, the number of parts of the elevator device does not increase.

  Further, according to the present embodiment, it is possible to diagnose an abnormality of the brake without providing the hoist or the brake body with the abnormality detecting device.

  Further, according to the reference value for judging the frictional force abnormality, it is possible to issue the abnormality report in a state where the brake does not reach the failure. As a result, the brake maintenance work can be performed when a sign of a failure is detected, so that the number of regular inspections of the brakes with the stop of the elevator can be reduced, and the interval of the brake inspection can be lengthened. Therefore, the total stop time of the elevator accompanying the maintenance and inspection work is reduced, so that the convenience of the elevator user is improved.

  Note that the present invention is not limited to the above-described embodiment, and includes various modified examples. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the described configurations. Further, for a part of the configuration of each embodiment, it is possible to add, delete, or replace another configuration.

  For example, the brake to be subjected to the abnormality diagnosis may be not only a drum brake (FIG. 2) but also a disc brake.

  Further, in the present embodiment (FIG. 1), the load detector 11 is provided above the car 9, but may be provided below the car, for example, in a car frame 50 below the car 9 in FIG.

  The elevator for which the abnormality of the brake is to be diagnosed may be an elevator in which a hoist and a control panel are installed in a machine room, or a so-called machine roomless in which the hoist and the control panel are installed in a hoistway. An elevator may be used.

  In addition, the abnormality alert may be sent to a monitoring center installed at a geographically distant place from the building where the elevator is installed, or may be sent to the building where the elevator is installed, for example, a management room or a control room. It may be sent to the room.

1 electric motor, 2 load calculation means, 3 torque / current control means,
4 surplus torque calculating means, 5 frictional force calculating means, 6 eccentric load detecting means,
7 Abnormal frictional force determination means, 8 sheave, 9 cages, 10 counterweights,
11 load detector, 50 car frame, 202 camera, 203 passenger,
204 elastic body for vibration isolation, 301 brake core, 302 brake spring,
303 brake drum, 304 brake lining, 305 brake shoe,
306 brake guide, 307 brake armature

Claims (6)

Diagnosis of the state of a brake that prevents rotation of the sheave by frictional force between a rotating body connected to a sheave driven by an electric motor and a brake lining, and issues an abnormality report when an abnormality is detected in the brake Abnormality diagnosis device for elevator brakes
A load sensor for measuring the load in the car,
Control means for creating a torque command value for controlling the electric motor,
The load measured by the load sensor, and an excess torque calculation unit that calculates an excess torque from the torque command value created by the control unit,
Frictional force calculating means for calculating the frictional force from the surplus torque calculated by the surplus torque calculating means,
Eccentric load detection means for detecting an eccentric load in the car,
Abnormal frictional force determining means for determining whether or not the brake is abnormal based on the frictional force calculated by the frictional force calculating means and the offset load detected by the offset load detecting means,
Bei to give a,
The abnormal frictional force determination unit, wherein the value of the frictional force is equal to or more than a predetermined reference value, and when there is the offset load in the car, it is determined that there is no abnormality in the brake, for the elevator Abnormal diagnostic device for brakes. The abnormality diagnosis device for an elevator brake according to claim 1,
The abnormal frictional force determination means, for a lift, wherein when the value of the frictional force is equal to or more than a predetermined reference value and there is no offset load in the car, the brake is determined to be abnormal . Abnormal diagnostic device for brakes. The abnormality diagnosis device for an elevator brake according to claim 1 ,
Further, a camera for photographing the inside of the car is provided,
The abnormality diagnosis device for an elevator brake, wherein the offset load detecting means detects the offset load based on an image in the car acquired by the camera . Te troubleshooting apparatus odor elevator brake according to claim 3,
The abnormality diagnosis device for an elevator brake, wherein the eccentric load detection means calculates a distribution of passengers in the car based on the image, and detects the eccentric load based on the distribution of passengers . Diagnosis of the state of a brake that prevents rotation of the sheave by frictional force between a rotating body connected to a sheave driven by an electric motor and a brake lining, and issues an abnormality report when an abnormality is detected in the brake Abnormality diagnosis method for elevator brakes
A first step of calculating excess torque from the load in the car and the torque command value of the electric motor,
A second step of calculating the frictional force from the surplus torque,
A third step of determining whether the brake is abnormal based on the frictional force calculated in the second step and the eccentric load in the car,
Including
In the third step,
If the value of the frictional force is equal to or more than a predetermined reference value, and there is the offset load in the car, it is determined that there is no abnormality in the brake,
If the value of the frictional force is equal to or greater than a predetermined reference value and the eccentric load does not exist in the car, it is determined that the brake has an abnormality. The abnormality diagnosis method for an elevator brake according to claim 5,
An abnormality diagnosis method for an elevator brake , wherein the presence or absence of the eccentric load is detected based on an image in the car .

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