Brake monitoring system

Abstract

The present invention provides a brake monitoring system that can automatically detect when a load exceeding a predetermined magnitude is applied to the brakes when high-load braking is performed on the holding brakes. [Solution] A brake monitoring system for use in a plant equipped with a motor for rotationally driving a machine and a brake for maintaining the motor in a stopped state is provided, comprising: a data acquisition unit for collecting data necessary for brake monitoring from external equipment; a brake energy calculation unit for calculating the braking energy absorbed by the brake based on the data collected by the data acquisition unit; and a detection unit for detecting that a load of a predetermined magnitude or greater has been applied to the brake when at least one of the temperature of the brake during braking and the braking energy calculated by the brake energy calculation unit exceeds a threshold.

Description

[Technical Field]

[0001] Embodiments of the present invention relate to a brake monitoring system. [Background technology]

[0002] Iron and non-ferrous metal industrial plants (steel plants) operate processing and manufacturing lines such as hot rolling lines, cold rolling lines, and process lines. The motors and brakes that drive these lines are numerous, sometimes exceeding 200 in a single line.

[0003] During normal operation, motor braking and deceleration are performed by the VVVF (Variable Voltage Variable Frequency) drive system that drives the motor. In other words, braking is rarely performed by the brakes themselves; brakes are mostly used to maintain the stopped state of the machine after the motor rotation has stopped under the control of the drive system. Furthermore, braking brakes are more expensive than holding brakes, and their larger size may prevent their installation due to mechanical constraints. Due to the factors mentioned above, the reality is that the brakes selected for ferrous and non-ferrous industrial plants are mostly for holding rather than braking.

[0004] Because the retaining brake is designed with a certain degree of tolerance, it will not immediately fail with slight braking. However, high-load braking can cause the brake unit to fail. Factors contributing to this failure include pad damage due to exceeding the amount of energy the brake can absorb, and overheating of the brake disc (drum) due to friction.

[0005] As mentioned above, most brakes used in ferrous and non-ferrous metal industrial plants are holding brakes. However, in situations where an emergency stop is necessary due to a serious failure of the drive system or other factors, the holding brake may be immediately tightened to apply braking force. In this case, since there is a possibility that the brakes have failed, all brakes must be inspected after the emergency stop, which can take a considerable amount of time before operations can be resumed. Furthermore, if a brake failure is discovered during the inspection, work such as replacing parts must be carried out, which will further prolong the time before operations can be resumed.

[0006] For example, a system has been proposed that compares the brake torque Fa when the brake is closed during operation at a constant speed with the theoretical brake torque Fi calculated from the tension and moment of inertia of the strip, and detects brake deterioration or abnormalities from the difference (for example, Patent Document 1). While this method can detect brake deterioration over time, it cannot detect brake deterioration or failure due to emergency stops, as described above.

[0007] Therefore, in plants that employ holding brakes, such as ferrous and non-ferrous metal industrial plants, it is desirable to be able to automatically detect when a load exceeding a predetermined magnitude is applied to the brakes when an emergency stop occurs, that is, when high-load braking that may exceed the brake's allowable workload is applied to the holding brakes, thereby enabling the detection of brake failure and protection of the brakes. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Application Publication No. 1-285558 [Overview of the Initiative] [Problems that the invention aims to solve]

[0009] Embodiments of the present invention provide a brake monitoring system that can automatically detect when a load exceeding a predetermined magnitude is applied to a brake when high-load braking is performed on a holding brake. [Means for solving the problem]

[0010] According to an embodiment of the present invention, a brake monitoring system is provided for use in a plant equipped with a motor for rotationally driving a machine and a holding brake for maintaining the stopped state of the motor, and for monitoring the brake, comprising: a data collection unit that collects data necessary for monitoring the brake from an external device by communicating with the external device; a brake energy calculation unit that calculates the braking energy absorbed by the brake when braking is performed by the brake based on the data collected by the data collection unit; and a detection unit that detects that a load of a predetermined magnitude or more has been applied to the brake when at least one of the temperature of the brake during braking and the braking energy calculated by the brake energy calculation unit exceeds a threshold. [Effects of the Invention]

[0011] A brake monitoring system is provided that can automatically detect when a load exceeding a predetermined magnitude is applied to the brakes when high-load braking is performed on the holding brakes. [Brief explanation of the drawing]

[0012] [Figure 1] This is a schematic diagram illustrating a portion of a ferrous and non-ferrous metals industrial plant. [Figure 2] This is a block diagram schematically representing a part of an iron and non-ferrous metals industrial plant. [Figure 3] This is a block diagram schematically representing the brake monitoring system. [Figure 4] This is a block diagram schematically representing a modified brake monitoring system. [Figure 5]It is a block diagram schematically showing a modified example of a brake monitoring system.

Embodiments for Carrying out the Invention

[0013] Hereinafter, each embodiment will be described with reference to the drawings. Note that the drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the ratio of the sizes between parts, etc. are not necessarily the same as the actual ones. Also, even when representing the same part, there are cases where their dimensions and ratios are represented differently in the drawings. In the specification of the present application and each drawing, the same elements as those described above with respect to the previously presented drawings are denoted by the same reference numerals, and detailed descriptions thereof are omitted as appropriate.

[0014] FIG. 1 is a schematic diagram schematically showing a part of an iron and non-iron industrial plant. As shown in FIG. 1, the iron and non-iron industrial plant 2 includes a tension reel 3. The tension reel 3 is a reel located at the end of a rolling line or the like of the iron and non-iron industrial plant 2, and is a machine that winds up the strip 4 supplied from an upstream machine in a coil shape. The strip 4 is a strip-shaped thin steel plate formed by rolling.

[0015] A tension T is applied to the strip 4. The tension reel 3 forms a coil 5 by winding up the strip 4 in a coil shape. Therefore, the diameter D of the coil 5 continuously increases.

[0016] The iron and non-iron industrial plant 2 further includes a motor 6, a speed sensor 7, and a brake 8. The motor 6 rotationally drives the tension reel 3. The tension reel 3 rotates based on the drive of the motor 6 to wind up the strip 4 in a coil shape. The speed sensor 7 measures the rotational speed of the motor 6. The speed sensor 7 is, for example, a rotary encoder attached to the rotating shaft of the motor 6. However, the speed sensor 7 is not limited thereto, and any sensor capable of measuring the rotational speed of the motor 6 may be used.

[0017] The brake 8 is a holding brake for maintaining the stopped state of the motor 6 after the rotation of the motor 6 stops. In other words, the brake 8 is a brake for maintaining the stopped state of the tension reel 3. The machine (rotating shaft) to which the brake 8 applies the holding force (braking force) may be any machine that transmits the rotational force between the motor 6 and the tension reel 3 (the machine that the motor 6 rotationally drives). The brake 8 is, for example, a disk brake, a drum brake, or the like.

[0018] Figure 2 is a block diagram schematically showing a part of an iron and non-iron industrial plant. As shown in Figure 2, the iron and non-iron industrial plant 2 further includes a control device 10, a drive device 12, and a brake control unit 14.

[0019] The control device 10 controls the drive device 12. The iron and non-iron industrial plant 2 includes, for example, a plurality of motors 6 for performing rolling and conveyance of the strip 4. The drive device 12 and the brake control unit 14 are provided, for example, for each of the plurality of motors 6. In other words, the iron and non-iron industrial plant 2 includes a plurality of drive devices 12 and a plurality of brake control units 14 corresponding to each of the plurality of motors 6. The control device 10 comprehensively controls, for example, the operations of each of the plurality of drive devices 12. The control device 10 is, for example, a PLC (programmable logic controller).

[0020] The control device 10 inputs, for example, a speed command representing the rotational speed of the motor 6 and a brake command representing the opening and closing of the brake 8 to the drive device 12. Further, the control device 10 inputs an emergency stop command for immediately stopping the rotation of the motor 6 to the drive device 12, for example, when an abnormality within the iron and non-iron industrial plant 2 is detected.

[0021] The drive device 12 receives the input of the speed command from the control device 10 and controls the rotation of the motor 6 according to the speed command. The drive device 12 controls the rotation of the motor 6 so as to achieve the rotational speed corresponding to the speed command. In other words, the drive device 12 drives the motor 6 according to the speed command.

[0022] Furthermore, the drive device 12 receives a brake command input from the control device 10 and controls the operation of the brake control unit 14 in accordance with the brake command. In other words, the drive device 12 drives the brake control unit 14 in accordance with the brake command. For example, the drive device 12 controls the operation of the brake control unit 14 by inputting a brake open signal and a brake closed signal to the brake control unit 14 in accordance with the brake command. The brake open signal is a signal that indicates the brake 8 should be in an open state. The brake closed signal is a signal that indicates the brake 8 should be in a closed state. The brake 8 being in an open state means that the brake 8 is not applying a holding force to the target machine, and the brake 8 being in a closed state means that the brake 8 is applying a holding force to the target machine.

[0023] When the drive device 12 receives an emergency stop command from the control device 10, it controls the motor 6 to stop, for example, and also inputs a brake closing signal to the brake control unit 14, thereby emergency stopping the rotation of the motor 6. In this way, the brake 8 applies braking force to the machine in question during an emergency, allowing the rotation of the motor 6 to be stopped more quickly.

[0024] The brake control unit 14 receives brake open signals and brake closed signals from the drive unit 12 and opens and closes the brake 8 in accordance with the brake open signals and brake closed signals. In other words, the brake control unit 14 switches between the open and closed states of the brake 8 in accordance with the brake open signals and brake closed signals. The emergency stop command may be input from the control device 10 to the drive unit 12, for example, in consideration of a failure in the drive unit 12, and may also be input directly from the control device 10 to the brake control unit 14. The brake control unit 14 may switch the brake 8 to the closed state in response to the emergency stop command input from the control device 10.

[0025] The speed sensor 7 measures the rotational speed of the motor 6 and transmits the measurement result to the control device 10 and drive device 12, which are higher-level systems. In other words, the speed sensor 7 feeds back the rotational speed of the motor 6 to the control device 10 and drive device 12. Based on the measurement result input from the speed sensor 7, the control device 10 and drive device 12 control the rotation of the motor 6 so that it reaches the rotational speed corresponding to the speed command.

[0026] Figure 3 is a block diagram schematically representing the brake monitoring system. As shown in Figure 3, the brake monitoring system 20 comprises a data acquisition unit 22, a temperature calculation unit 24, a braking energy calculation unit 26, and a detection unit 28. The brake monitoring system 20 is used in the ferrous and non-ferrous metals industrial plant 2 to monitor the brakes 8. In other words, the ferrous and non-ferrous metals industrial plant 2 is further equipped with the brake monitoring system 20.

[0027] The brake monitoring system 20 is provided, for example, in relation to each of the multiple brakes 8 installed in the ferrous / non-ferrous metals industrial plant 2. The ferrous / non-ferrous metals industrial plant 2 is equipped with, for example, multiple brake monitoring systems 20, each corresponding to one of the multiple brakes 8. In this way, the ferrous / non-ferrous metals industrial plant 2 monitors each of the multiple brakes 8 using the multiple brake monitoring systems 20. However, it is also possible to configure it so that one brake monitoring system 20 monitors multiple brakes 8. The number of brake monitoring systems 20 does not necessarily have to be the same as the number of brakes 8.

[0028] The data acquisition unit 22 communicates with the control device 10 to collect data necessary for monitoring the brake 8 from the control device 10. The data acquisition unit 22 also stores the collected data, for example.

[0029] The data acquisition unit 22 collects data on the rotational speed of the motor 6 measured by the speed sensor 7, data on the braking time of the brake 8 when braking is performed with the holding brake 8 (when the motor 6 is brought to an emergency stop), and data on the moment of inertia of the coil 5. In Figure 3, the moment of inertia is denoted as GD2 for convenience.

[0030] The data acquisition unit 22 collects data from the control device 10 that represents the timing of switching the brake 8 to the closed state when performing braking (when emergency stopping the rotation of the motor 6) with the brake 8. The data acquisition unit 22 calculates the braking time of the brake 8 based on the elapsed time from the timing of switching the brake 8 to the closed state. However, the data on the braking time of the brake 8 may be collected directly from the control device 10, for example. The method of collecting the data on the braking time of the brake 8 is not limited to the above and may be any method.

[0031] The data acquisition unit 22, for example, collects data on the diameter D of the coil 5 from the control device 10. The control device 10 is interfaced with all drive devices 12 in the ferrous and non-ferrous industrial plant 2, even when the motor 6 is in an emergency stop, and collects and stores data such as the rotational speed of all motors 6, the diameter D of the coil 5, and the tension T of the strip 4. The diameter D of the coil 5 is measured by, for example, a distance meter (not shown). The tension T of the strip 4 is measured by, for example, a tension meter (not shown). The method for measuring the diameter D of the coil 5 and the tension T of the strip 4 is not limited to the above and may be any method.

[0032] The data acquisition unit 22 receives, for example, data on the width of the strip 4 and data on the density of the material of the strip 4 from the control device 10. The data acquisition unit 22 calculates the weight of the coil 5 from, for example, the diameter D of the coil 5, the width of the strip 4, and the density of the material. Then, the data acquisition unit 22 calculates the moment of inertia of the coil 5 based on, for example, the calculated weight and the diameter D of the coil 5. However, the method for calculating the moment of inertia of the coil 5 is not limited to the above and may be any method. In addition, the data for the moment of inertia of the coil 5 may be collected directly from, for example, the control device 10. The method for collecting the data for the moment of inertia of the coil 5 is not limited to the above and may be any method.

[0033] The data acquisition unit 22 inputs the rotational speed data of the motor 6 and the braking time data of the brake 8 to the temperature calculation unit 24. Then, the data acquisition unit 22 inputs the rotational speed data of the motor 6 and the moment of inertia data of the coil 5 to the braking energy calculation unit 26.

[0034] It should be noted that data collection by the data collection unit 22 is not necessarily limited to communication with the control device 10. The data collection unit 22 may, for example, directly collect rotational speed data of the motor 6 from the speed sensor 7 by communicating with the speed sensor 7. The data collection unit 22 collects data by communicating with external devices. The external devices are not limited to the control device 10, but may be any devices that hold the necessary data. The data collection unit 22 may, for example, collect data from multiple external devices.

[0035] The temperature calculation unit 24 calculates the temperature of the brake 8 during braking based on the data collected by the data acquisition unit 22. The temperature calculation unit 24 inputs the calculated temperature of the brake 8 during braking to the detection unit 28.

[0036] The temperature calculation unit 24 has data on the physical eigenvalues ​​of the brake 8, such as the outer diameter of the brake disc, friction coefficient, braking torque, and heat capacity. Based on the rotational speed data of the motor 6, the braking time data of the brake 8, and the eigenvalue data of the brake 8, which are input from the data acquisition unit 22, the temperature calculation unit 24 calculates the temperature of the brake 8 during braking.

[0037] The amount of heat generated by braking, Q (kcal / min), can be calculated, for example, by using the friction coefficient of brake 8 as μ and the surface pressure of brake 8 as P (kgf / cm²). 2 When the rotational speed of motor 6 (rotating shaft) is V (m / min) and the work equivalent of heat is J (kgf·m / kcal), it can be calculated using the following formula. Q = μ·P·V / J The surface pressure P is calculated, for example, based on the outer diameter of the brake disc 8 and the braking torque.

[0038] The temperature rise ΔT of the brake 8 due to the amount of heat Q can be calculated, for example, by the following equation, when the heat capacity of the brake 8 is C. Δt = Q / C Therefore, the temperature T of the brake 8 during braking can be calculated by adding the temperature rise ΔT to the temperature T0 of the brake 8 before braking begins (e.g., room temperature). T = T0 + ΔT

[0039] However, the method by which the temperature calculation unit 24 calculates the temperature of the brake 8 during braking is not limited to the above, and any method that can appropriately calculate the temperature of the brake 8 during braking based on the data collected by the data acquisition unit 22 and the pre-stored eigenvalue data of the brake 8 may be used.

[0040] The braking energy calculation unit 26 calculates the braking energy absorbed by the brake 8 when braking is performed using the brake 8, based on the data collected by the data collection unit 22. The braking energy calculation unit 26 inputs the calculated braking energy to the detection unit 28.

[0041] The braking energy calculation unit 26 has data on the eigenvalues of the brake 8 and the machine driven by the brake 8, such as, for example, the moment of inertia of the motor 6, the moment of inertia of the machine (such as the tension reel 3, etc.) rotationally driven by the motor 6, and the braking torque of the brake 8. The machine rotationally driven by the motor 6 is, for example, all the machines (connected to the motor 6) rotationally driven by the motor 6, such as the tension reel 3 and the machine that transmits the driving force of the motor 6 to the tension reel 3.

[0042] The braking energy calculation unit 26 calculates the braking energy absorbed by the brake 8 during braking based on, for example, the data on the rotational speed of the motor 6 input from the data collection unit 22, the data on the moment of inertia of the coil 5, and the data on the eigenvalues of the brake 8 and the machine driven by the brake 8.

[0043] The braking energy calculation unit 26, for example, sets the braking torque as T q (kgf·m), sets the friction torque with the torque in the direction of stopping rotation as positive as T L (kgf·m), sets the moment of inertia of the motor 6 as GD 2 M (kgf·m 2 ), sets the moment of inertia of the machine rotationally driven by the motor 6 as GD 2 L (kgf·m 2 ), and when the rotational speed of the motor 6 is rpm (r / min), calculates the braking energy En (kgf·m) based on the following (1).

Equation

[0044] In the formula (1), the friction torque T L is calculated based on, for example, the tension T of the strip 4. Also, the moment of inertia of the machine GD 2 LMore specifically, this is the sum of the moment of inertia of the machine and the moment of inertia of coil 5, which are stored as eigenvalue data.

[0045] However, the method for calculating braking energy by the braking energy calculation unit 26 is not limited to the above, and any method that can appropriately calculate braking energy based on data collected by the data acquisition unit 22 and pre-stored data of the brake 8 and the eigenvalues ​​of the machine rotated by the brake 8 may be used.

[0046] The detection unit 28 determines whether the temperature of the brake 8 during braking, calculated by the temperature calculation unit 24, is above a threshold, and also determines whether the braking energy calculated by the braking energy calculation unit 26 is above a threshold. When the detection unit 28 determines that at least one of the temperature during braking and the braking energy is above a threshold, it detects that a load of a predetermined magnitude or greater has been applied to the brake 8. In other words, when at least one of the temperature during braking and the braking energy is above a threshold, the detection unit 28 detects that a load of a predetermined magnitude or greater has been applied to the brake 8.

[0047] The detection unit 28 sets, for example, the threshold values ​​for temperature and braking energy during braking to the allowable values ​​of the brake 8. That is, the detection unit 28 detects when at least one of the temperature and braking energy during braking exceeds the allowable value.

[0048] If at least one of the temperature and braking energy during braking exceeds an allowable value, the brake 8 may be malfunctioning. In this case, the detection unit 28, upon detecting that a load exceeding a predetermined magnitude has been applied to the brake 8, outputs a malfunction detection signal indicating the possibility of brake 8 malfunction.

[0049] The detection unit 28 outputs a fault detection signal to, for example, the terminal of the manager of the ferrous / non-ferrous metals industrial plant 2. The manager's terminal has a display unit, and in response to the input of the fault detection signal from the detection unit 28, it displays the possibility of brake 8 failure on the display unit. This makes it possible to notify the manager of the ferrous / non-ferrous metals industrial plant 2 of the possibility of brake 8 failure.

[0050] In this way, the detection unit 28 outputs a fault detection signal to an external device having a display unit, for example, so that the possibility of brake 8 failure can be displayed on the display unit of the external device. The external device is not limited to the terminal of the manager of the ferrous / non-ferrous industrial plant 2, but can be any device having a display unit that is capable of appropriately notifying the manager of the ferrous / non-ferrous industrial plant 2 of the possibility of brake 8 failure. The external device may be, for example, a mobile terminal such as a smartphone owned by the manager of the ferrous / non-ferrous industrial plant 2.

[0051] Furthermore, the brake monitoring system 20 may also include, for example, a display unit. The detection unit 28 may output a fault detection signal to a dedicated display unit of the brake monitoring system 20 and display the possibility of brake 8 failure on the dedicated display unit of the brake monitoring system 20, thereby notifying the manager of the ferrous / non-ferrous industrial plant 2 of the possibility of brake 8 failure.

[0052] The fault detection signal includes information on the cause of the failure, indicating, for example, whether the brake 8 is likely to fail due to temperature during braking or braking energy. This allows, for example, the possibility of brake 8 failure to be displayed on the display unit, as well as the cause of the failure.

[0053] The detection unit 28 outputs a fault detection signal to an external device and also outputs it to the data acquisition unit 22. The data acquisition unit 22 stores (stores) the fault detection signal input from the detection unit 28. Then, the data acquisition unit 22 outputs the stored fault detection signal to an external device in response to a request from an external device such as a terminal of the administrator of the ferrous / non-ferrous industrial plant 2. This makes it possible to display, for example, the history of past fault detections, the faulty brake 8 and its cause on the external device. For example, based on multiple fault detection signals detected in the past, it is possible to analyze which of the multiple brakes 8 installed in the ferrous / non-ferrous industrial plant 2 are prone to failure due to braking.

[0054] Furthermore, the detection unit 28 outputs a fault detection signal to the control device 10, for example. This allows a higher-level system, such as the control device 10, to recognize the possibility of a brake 8 failure (detection that a load exceeding a predetermined magnitude has been applied to the brake 8).

[0055] As described above, in the brake monitoring system 20 according to this embodiment, the detection unit 28 detects that a load of a predetermined magnitude or greater has been applied to the brake 8 when at least one of the temperature and braking energy during braking exceeds a threshold. In this way, the brake monitoring system 20 according to this embodiment can automatically detect that a load of a predetermined magnitude or greater has been applied to the brake 8 when high-load braking is performed on the holding brake 8.

[0056] Furthermore, in the brake monitoring system 20, the detection unit 28 sets the temperature threshold and braking energy threshold during braking to the allowable values ​​of the brake 8, and outputs a fault detection signal indicating the possibility of brake 8 failure when it detects that a load exceeding a predetermined magnitude has been applied to the brake 8. This makes it possible to notify external equipment, for example, of the possibility of brake 8 failure. Even in the case of unavoidable braking in the ferrous / non-ferrous industrial plant 2, where the holding brake 8 has been selected, it is possible to detect the possibility of brake 8 failure.

[0057] For example, by outputting a fault detection signal to an external device with a display unit, the possibility of brake 8 failure can be displayed on the external device's display unit. In this case, only the brake 8 that may have failed can be picked out and displayed from among the multiple brakes 8 installed in the ferrous / non-ferrous industrial plant 2, eliminating the need to inspect and maintain all brakes 8. This reduces the time required for restoration work to resume operations in the event of an emergency stop, and is expected to improve the operating rate.

[0058] Figure 4 is a block diagram schematically representing a modified brake monitoring system. As shown in Figure 4, in the brake monitoring system 20a, the detection unit 28a sets the temperature threshold and the braking energy threshold during braking to values ​​that are each lower by a predetermined amount than the allowable values ​​of the brake 8. Then, in response to the detection unit 28a detecting that a load exceeding a predetermined magnitude has been applied to the brake 8, it outputs a brake open signal indicating that the brake 8 should be opened. Components that are substantially the same in function and configuration as in the above embodiment are denoted by the same reference numerals, and detailed explanations are omitted.

[0059] The detection unit 28a outputs a brake open signal to the brake control unit 14, for example. This allows the brake monitoring system 20a to switch the brake 8 to an open state before the temperature and braking energy during braking exceed the allowable values ​​and the brake 8 fails. Therefore, the brake monitoring system 20a can suppress brake 8 failure and protect the brake 8 even when braking is unavoidable in an iron / non-ferrous metals industrial plant 2 where a holding brake 8 has been selected.

[0060] The brake monitoring system 20a protects the brake 8 even when braking is performed using the holding brake 8, thereby reducing the effort required for inspecting and maintaining the brake 8. This makes it possible to further shorten the time required for restoration work to resume operations in the event of an emergency stop, thereby improving the operating rate of the ferrous and non-ferrous metals industrial plant 2.

[0061] Furthermore, the detection unit 28a may output a brake open signal to the control device 10 or the drive device 12, not limited to the brake control unit 14. The device to which the brake open signal is output is not limited to the above, and may be any device capable of appropriately switching the brake 8 to an open state by outputting the brake open signal.

[0062] When a brake open signal is output to the control device 10, for example, it is possible to make the control device 10 or other higher-level systems recognize that a load exceeding a predetermined magnitude has been applied to the brake 8, and that the brake 8 has been switched to an open state in response to this detection.

[0063] Figure 5 is a block diagram schematically representing a modified brake monitoring system. As shown in Figure 5, in the brake monitoring system 20b, the temperature calculation unit 24 is replaced by a temperature measurement unit 30. The temperature measurement unit 30 measures the temperature of the brake 8 during braking. The temperature measurement unit 30 measures, for example, the surface temperature of the brake 8 disc. The temperature measurement unit 30 uses, for example, a non-contact temperature sensor such as an infrared thermometer. However, the temperature measurement unit 30 is not limited to the above and may be any sensor capable of appropriately measuring the temperature of the brake 8 during braking. The temperature measurement unit 30 inputs the measured temperature of the brake 8 during braking to the detection unit 28b.

[0064] The detection unit 28b determines whether the temperature of the brake 8 during braking, as measured by the temperature measurement unit 30, is above a threshold. When at least one of the temperature of the brake 8 during braking, as measured by the temperature measurement unit 30, and the braking energy calculated by the braking energy calculation unit 26, exceeds the threshold, the detection unit 28b detects that a load of a predetermined magnitude or greater has been applied to the brake 8.

[0065] Thus, the temperature of the brake 8 during braking is not limited to the temperature calculated by the temperature calculation unit 24, but may also be the temperature measured by the temperature measurement unit 30. In this case as well, similar to the above embodiment, when high-load braking is performed on the holding brake 8, it is possible to automatically detect when a load exceeding a predetermined magnitude is applied to the brake 8.

[0066] In each of the above embodiments, a motor 6 that rotates the tension reel 3 and a brake 8 that holds the motor 6 in a stopped state are shown. The motor may be, for example, a motor that rotates a bridle roller installed in the ferrous / non-ferrous industrial plant 2. The motor is not limited to this, and may be any motor that rotates a machine installed in the ferrous / non-ferrous industrial plant 2. The brake may be any brake that holds the motor in a stopped state installed in the ferrous / non-ferrous industrial plant 2.

[0067] In each of the above embodiments, the brake monitoring systems 20, 20a, and 20b are provided separately from the control device 10. The brake monitoring systems 20, 20a, and 20b may be provided, for example, in the control device 10, the drive device 12, or the brake control unit 14. In this case, there is no need to add a new PLC or the like for the brake monitoring systems 20, 20a, and 20b, and the configuration of the ferrous / non-ferrous industrial plant 2 can be made simpler. Even when the brake monitoring systems 20, 20a, and 20b are provided in the ferrous / non-ferrous industrial plant 2, it is possible to suppress increases in the number of parts of the ferrous / non-ferrous industrial plant 2 and increases in manufacturing costs.

[0068] The embodiments described above show examples of applying the brake monitoring systems 20, 20a, and 20b to an iron / non-ferrous metals industrial plant 2. The brake monitoring systems 20, 20a, and 20b are not limited to an iron / non-ferrous metals industrial plant 2, but may also be applied to, for example, a paper mill. The plants to which the brake monitoring systems 20, 20a, and 20b are applied are not limited to those described above, but may be any plants that have the possibility of performing braking with the holding brake 8.

[0069] This embodiment includes the following aspects. (Note 1) A brake monitoring system used in a plant equipped with a motor for rotationally driving a machine and a holding brake for maintaining the stopped state of the motor, which monitors the brake, A data acquisition unit that collects data necessary for monitoring the brakes from an external device by communicating with the external device, A braking energy calculation unit calculates the braking energy absorbed by the brake when braking is performed using the brake, based on the data collected by the data collection unit. A detection unit detects that a load of a predetermined magnitude or greater is applied to the brake when at least one of the temperature of the brake during braking and the braking energy calculated by the braking energy calculation unit exceeds a threshold, when braking is performed with the brake, Equipped with a brake monitoring system.

[0070] (Note 2) The brake monitoring system according to Appendix 1, wherein the detection unit sets the threshold temperature and the threshold braking energy to allowable values ​​for the brake, and outputs a fault detection signal indicating the possibility of brake failure in response to the detection that a load exceeding a predetermined magnitude has been applied to the brake.

[0071] (Note 3) The fault detection signal includes information on the cause of the failure, indicating whether the brake failure is due to the temperature during braking or the braking energy. The detection unit outputs the fault detection signal to the data acquisition unit. The brake monitoring system according to Appendix 2, wherein the data acquisition unit stores the fault detection signal input from the detection unit and outputs the stored fault detection signal to an external device in response to a request from the external device.

[0072] (Note 4) The brake monitoring system according to Appendix 1, wherein the detection unit sets the threshold temperature and the threshold braking energy during braking to values ​​that are each lower by a predetermined amount than the allowable value of the brake, and outputs a brake open signal indicating that the brake should be opened when it is detected that a load of a predetermined magnitude or greater has been applied to the brake.

[0073] (Note 5) The system further includes a temperature calculation unit that calculates the temperature of the brakes during braking based on the data collected by the data acquisition unit. The brake monitoring system according to any one of Appendix 1 to 4, wherein the detection unit detects that a load of a predetermined magnitude or greater has been applied to the brake when at least one of the temperature of the brake during braking calculated by the temperature calculation unit and the braking energy calculated by the braking energy calculation unit exceeds a threshold.

[0074] (Note 6) The system further includes a temperature measuring unit for measuring the temperature of the brakes during braking, The brake monitoring system according to any one of the appendices 1 to 4, wherein the detection unit detects that a load of a predetermined magnitude or greater has been applied to the brake when at least one of the temperature of the brake during braking, measured by the temperature measurement unit, and the braking energy calculated by the braking energy calculation unit, exceeds a threshold.

[0075] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0076] 2…Ferrous and non-ferrous metal industrial plant, 3…Tension reel, 4…Strip, 5…Coil, 6…Motor, 7…Speed ​​sensor, 8…Brake, 10…Control device, 12…Drive device, 14…Brake control unit, 20, 20a, 20b…Brake monitoring system, 22…Data acquisition unit, 24…Temperature calculation unit, 26…Braking energy calculation unit, 28, 28a, 28b…Detection unit, 30…Temperature measurement unit

Claims

1. A brake monitoring system used in a plant equipped with a motor for rotationally driving a machine and a holding brake for maintaining the stopped state of the motor, which monitors the brake, A data acquisition unit that collects data necessary for monitoring the brakes from an external device by communicating with the external device, A braking energy calculation unit calculates the braking energy absorbed by the brake when braking is performed using the brake, based on the data collected by the data collection unit. A detection unit detects that a load of a predetermined magnitude or greater is applied to the brake when at least one of the temperature of the brake during braking and the braking energy calculated by the braking energy calculation unit exceeds a threshold, when braking is performed with the brake, Equipped with a brake monitoring system.

2. The brake monitoring system according to claim 1, wherein the detection unit sets the threshold temperature and the threshold braking energy to allowable values ​​for the brake, and outputs a fault detection signal indicating the possibility of brake failure in response to the detection that a load exceeding a predetermined magnitude has been applied to the brake.

3. The fault detection signal includes information on the cause of the failure, indicating whether the brake failure is due to the temperature during braking or the braking energy. The detection unit outputs the fault detection signal to the data acquisition unit. The brake monitoring system according to claim 2, wherein the data acquisition unit stores the fault detection signal input from the detection unit and outputs the stored fault detection signal to an external device in response to a request from the external device.

4. The brake monitoring system according to claim 1, wherein the detection unit sets the threshold temperature and the threshold braking energy during braking to a predetermined value lower than the allowable value of the brake, and outputs a brake open signal indicating that the brake should be opened when it detects that a load of a predetermined magnitude or greater has been applied to the brake.

5. The system further includes a temperature calculation unit that calculates the temperature of the brakes during braking based on the data collected by the data acquisition unit. The brake monitoring system according to claim 1, wherein the detection unit detects that a load of a predetermined magnitude or greater has been applied to the brake when at least one of the temperature of the brake during braking calculated by the temperature calculation unit and the braking energy calculated by the braking energy calculation unit exceeds a threshold.

6. The system further includes a temperature measuring unit for measuring the temperature of the brakes during braking, The brake monitoring system according to claim 1, wherein the detection unit detects that a load of a predetermined magnitude or greater has been applied to the brake when at least one of the temperature of the brake during braking, measured by the temperature measurement unit, and the braking energy calculated by the braking energy calculation unit, exceeds a threshold.

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