Elevator Brake Real-time Status Monitoring / Early Warning System

Abstract

The present invention provides a real-time status monitoring / warning system for an elevator brake, comprising: a traction machine, a brake, a sensor subsystem, a logic subsystem, and a final element subsystem; the sensor subsystem is connected to the logic subsystem; the logic subsystem is connected to the final element subsystem; the sensor subsystem includes: sensor components; the real-time status monitoring / warning system for the elevator brake includes: an elevator system, an elevator brake, sensor components, an input module, a logic processing module, and a warning / output module; the final element subsystem can cut off the power supply of the brake in a timely manner when a failure or danger occurs. By connecting the output switch of the monitoring system to the safety circuit, the present invention solves the control of the system power supply and ensures the safety of personnel and equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of real-time status monitoring, and in particular, to a real-time status monitoring / warning system for an elevator brake. Background Art

[0002] For a long time, electrical detection, factory equipment detection, mechanical detection, and regular spot-check overall tests have been widely used for elevator brakes to ensure the normal operation of the brakes. However, this detection method still has obvious deficiencies: (1) If a fault occurs during the detection, an accident has already occurred; (2) It is difficult to control the interval time for regular spot checks. If the interval is too long, the safety between detections cannot be ensured, and if the interval is too short, it will cause waste. At the same time, in the process of data analysis, information data from a single source is mostly used, and diagnosis and warning are carried out based on expert experience, lacking precise quantitative analysis.

[0003] Patent document CN107814288A discloses a method for intelligent monitoring and warning of an elevator brake, which uses a non-contact measurement method to collect key parameters and gives the operating state of the machine based on SVM clustering analysis. The deficiencies of the prior art are as follows: The main function of the monitoring system is to monitor the operating state of the brake and record relevant operating data, and rely on expert experience to analyze and judge according to the change curve of physical parameters, lacking research on fault warning algorithms; at the same time, the monitoring system itself has not passed functional safety certification, and the reliability and safety during operation cannot be effectively guaranteed, so it cannot meet the requirements of the functional safety of the elevator itself. Summary of the Invention

[0004] Aiming at the deficiencies in the prior art, the purpose of the present invention is to provide a real-time status monitoring / warning system for an elevator brake.

[0005] According to a real-time status monitoring / warning system for an elevator brake provided by the present invention, it includes: a traction machine, a brake, a sensor subsystem, a logic subsystem, and a final element subsystem;

[0006] The sensor subsystem is connected to the logic subsystem;

[0007] The logic subsystem is connected to the final element subsystem;

[0008] The sensor subsystem includes: sensor components;

[0009] The real-time status monitoring / warning system for an elevator brake includes: an elevator system, an elevator brake, sensor components, an input module, a logic processing module, and a warning / output module;

[0010] The elevator system and the elevator brake are respectively connected to the sensor components;

[0011] The input module is connected to the sensor component;

[0012] The input module is connected to the logic processing module;

[0013] The logic processing module is connected to the warning / output module;

[0014] The final element subsystem is connected to the brake;

[0015] The final element subsystem can cut off the power supply of the brake in time when a fault or danger occurs.

[0016] Preferably, the sensor component includes: an AC voltage sensor and an AC current sensor;

[0017] The AC voltage sensor and the AC current sensor are respectively connected to the elevator system;

[0018] The AC voltage sensor and the AC current sensor are respectively connected to the input module.

[0019] Preferably, the sensor component includes: a displacement sensor, a temperature sensor, a DC voltage sensor, a DC current sensor, and a noise sensor;

[0020] The displacement sensor, the temperature sensor, the DC voltage sensor, the DC current sensor, and the noise sensor are respectively connected to the elevator brake;

[0021] The displacement sensor, the temperature sensor, the DC voltage sensor, the DC current sensor, and the noise sensor are respectively connected to the input module.

[0022] Preferably, the sensor subsystem further includes: a rotary encoder;

[0023] The rotary encoder is connected to the elevator system;

[0024] The rotary encoder is connected to the input module.

[0025] Preferably, the sensor subsystem further includes: a microswitch;

[0026] The microswitch is connected to the elevator brake;

[0027] The microswitch is connected to the input module.

[0028] Preferably, it further includes: a DC current transmitter and a perforated AC current transmitter;

[0029] The AC voltage sensor, the AC current sensor, the DC voltage sensor, and the DC current sensor are connected in parallel to the positive and negative poles of the brake coil to monitor the brake coil voltage;

[0030] The DC current transmitter is connected in series to the circuit of the brake to monitor the current;

[0031] The perforated AC current transmitter monitors the output current of the traction machine.

[0032] Preferably, the temperature sensor uses a J-type linear thermocouple.

[0033] Preferably, the displacement sensor uses a laser displacement sensor.

[0034] Preferably, the rotary encoder uses a Heidenhain absolute encoder.

[0035] Preferably, the logic subsystem includes: an MCU component, a power module, a power supply monitoring module, a watchdog module, and a storage module.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. By using the encoder readings, brake gap, friction noise, brake voltage, brake current, coil temperature, and microswitch response time as the data objects collected by the monitoring system, the present invention solves the problems of identifying physical phenomena such as too small braking distance, too large air gap, worn friction pads, too low coil voltage, too low coil current, coil overheating, residual voltage and current of the coil, and insufficient spring force.

[0038] 2. By connecting the output switch of the monitoring system to the safety circuit, the present invention solves the control of the system power supply and ensures the safety of personnel and equipment.

[0039] 3. By using the master and slave dual systems to simultaneously monitor the operating state of the brake, the present invention solves the problem that when one of the two channels has a random failure, the system will enter a safe state. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] By reading the following detailed description of the non-limiting embodiments with reference to the accompanying drawings, other features, objects, and advantages of the present invention will become more apparent:

[0041] Figure 1 It is a schematic diagram of the overall structural framework of the present invention.

[0042] Figure 2 It is a schematic diagram of the overall hardware framework of the elevator brake monitoring system in the embodiment of the present invention.

[0043] Figure 3 It is a schematic diagram of the overall framework of the sensor subsystem in the embodiment of the present invention.

[0044] Figure 4 It is a schematic diagram of the overall layout of the sensors in the embodiment of the present invention.

[0045] Figure 5 Schematic diagram of the output circuit module design in the embodiment of the present invention.

[0046] Figure 6 Schematic diagram of the elevator safety circuit in the embodiment of the present invention.

[0047] In the figure:

[0048] K - Output switch of the elevator brake monitoring system; BRAKE - Elevator brake

[0049] M - Traction machine KM1 - Traction machine contactor Specific implementation manners

[0050] The present invention will be described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several changes and improvements can still be made. These all belong to the protection scope of the present invention.

[0051] According to an elevator brake real - time status monitoring / warning system provided by the present invention, it includes: a traction machine, a brake, a sensor subsystem, a logic subsystem, and a final element subsystem;

[0052] The sensor subsystem is connected to the logic subsystem;

[0053] The logic subsystem is connected to the final element subsystem;

[0054] The sensor subsystem includes: sensor components;

[0055] The elevator brake real - time status monitoring / warning system includes: an elevator system, an elevator brake, sensor components, an input module, a logic processing module, and a warning / output module;

[0056] The elevator system and the elevator brake are respectively connected to the sensor components;

[0057] The input module is connected to the sensor components;

[0058] The input module is connected to the logic processing module;

[0059] The logic processing module is connected to the warning / output module;

[0060] The final element subsystem is connected to the brake;

[0061] The final element subsystem can cut off the power supply of the brake in time when a fault or danger occurs.

[0062] Preferably, the sensor component includes: an AC voltage sensor and an AC current sensor;

[0063] The AC voltage sensor and the AC current sensor are respectively connected to the elevator system;

[0064] The AC voltage sensor and the AC current sensor are respectively connected to the input module.

[0065] Preferably, the sensor component includes: a displacement sensor, a temperature sensor, a DC voltage sensor, a DC current sensor, and a noise sensor;

[0066] The displacement sensor, the temperature sensor, the DC voltage sensor, the DC current sensor, and the noise sensor are respectively connected to the elevator brake;

[0067] The displacement sensor, the temperature sensor, the DC voltage sensor, the DC current sensor, and the noise sensor are respectively connected to the input module.

[0068] Preferably, the sensor subsystem further includes: a rotary encoder;

[0069] The rotary encoder is connected to the elevator system;

[0070] The rotary encoder is connected to the input module.

[0071] Preferably, the sensor subsystem further includes: a microswitch;

[0072] The microswitch is connected to the elevator brake;

[0073] The microswitch is connected to the input module.

[0074] Preferably, it further includes: a DC current transmitter and a through-hole AC current transmitter;

[0075] The AC voltage sensor, the AC current sensor, the DC voltage sensor, and the DC current sensor are connected in parallel to the positive and negative poles of the brake coil to monitor the brake coil voltage;

[0076] The DC current transmitter is connected in series to the brake circuit to monitor the current;

[0077] The through-hole AC current transmitter monitors the output current of the traction machine.

[0078] Preferably, the temperature sensor uses a J-type linear thermocouple.

[0079] Preferably, the displacement sensor uses a laser displacement sensor.

[0080] Preferably, the rotary encoder adopts a Heidenhain absolute encoder.

[0081] Preferably, the logic subsystem includes: an MCU component, a power supply module, a power supply monitoring module, a watchdog module, and a storage module.

[0082] The elevator brake monitoring system can monitor temperature, noise, electrical signals, encoder signals, and microswitch signals in real time, and realize the random fault judgment of the elevator brake and the fault warning of brake failure. It meets the design requirements of hardware safety integrity for SIL2 (Safety Integrity Level 2).

[0083] Specifically, in one embodiment, the real-time status monitoring / warning system of the elevator brake is divided into three subsystems according to the functional requirements and reliability requirements of the monitoring system, namely the sensor subsystem, the logic subsystem, and the final element subsystem.

[0084] The sensor subsystem of the elevator brake monitoring system is mainly composed of a thermocouple, a voltage and current sensor, a noise sensor, a laser displacement sensor, an encoder, and a microswitch signal, which are respectively used to measure the changes of analog and digital quantities such as coil temperature, voltage and current, braking noise, wear degree, braking distance, and brake response time during the braking and releasing processes of the brake.

[0085] 1. Voltage and current sensor. The voltage and current sensor is connected in parallel to the positive and negative poles of the brake coil to monitor the brake coil voltage; the DC current transmitter is connected in series in the brake circuit to monitor the current; the perforated AC current transmitter monitors the output current of the traction machine.

[0086] 2. Temperature sensor. A J-type linear thermocouple with high sensitivity, stability, and uniformity is used as the temperature sensor, which is buried in the coil to detect the high temperature generated by the coil under continuous power supply when the elevator brake is working.

[0087] 3. Noise sensor. During the process of the brake from normal operation to failure, the brake pads will gradually wear, and the sound generated by its braking will change. The noise sensor is installed outside the electrical cabinet, with the mic port facing the brake, and the distance is set to 5m, which can monitor the changes (sound intensity, audio frequency) of the abnormal sound generated by the braking, so as to capture the abnormal situation of the braking.

[0088] 4. Displacement sensor. A laser displacement sensor is used to indirectly measure the gap between the brake wheel and the brake shoe and the wear amount of the brake shoe.

[0089] 5. Encoder. The elevator brake encoder is a Heidenhain absolute encoder. The incremental signal output is orthogonal sine and cosine signals. The orthogonal analog signal is converted into a pulse signal to obtain the required orthogonal pulse signal as the output.

[0090] 6. Microswitch. The 24V digital quantity of the microswitch is provided by the PLC, and the signal is collected by the data acquisition and control board. The microswitch is mainly used for the following two functions: 1. When the coil in the electromagnetic coil is energized, the armature disk is pulled towards the coil bracket, and the microswitch emits a signal when the brake is in place, so as to judge the opening response time of the brake; 2. When the brake is de-energized, the armature disk returns to the initial position, and the microswitch signal returns to the low level again. The closing response time is deduced based on the low level time obtained by the chip and the power-off time of the brake.

[0091] The logic subsystem of the elevator brake monitoring system mainly includes a highly reliable MCU, a power supply module, a power supply monitoring module, a watchdog module and a storage module.

[0092] The function of the final element subsystem of the elevator brake monitoring system is to cut off the power supply of the traction machine and the brake in time when a fault or danger is judged. Therefore, it can be regarded as the output of a safety relay connected to the safety circuit. By connecting the relay output of the system to the safety circuit, the power supply of the traction machine and the brake is controlled.

[0093] In the elevator brake monitoring system, the system is divided into a master module and a slave module. The master and slave modules can each complete the function of monitoring the running state of the brake. The MCUs of the master and slave modules communicate with each other through SPI. Since the structures of the two modules are exactly the same, the functions of each module will be described below based on the master module. The AD processing module is used to receive, collect and process the analog quantities measured by each sensor; the optocoupler input module is used to collect the signal of the microswitch to judge the braking and opening actions of the brake; the RTC module, as a clock module, is used to save and record the time of the fault; the watchdog module is used to reset the system when an error occurs in the MCU; the human-machine interface is used to display the fault code and the remaining life of the machine; the EEPROM is used to store the fault information and the parameters related to the elevator brake; the power supply circuit provides power for the system, and the power supply monitoring ensures that the power supply voltage state of the system remains normal; the relay, as an output component, is connected in series in the safety circuit. When one of the relays of the master and slave modules is disconnected, the safety circuit is automatically disconnected and the system is powered off to enter a safe state.

[0094] The design module of the output circuit is as Figure 5As shown in the figure, two relays are respectively controlled by their respective MCUs in two modules, A and B. When the initialization of the two MCUs is completed and the interactive information is normal, the two relays are opened simultaneously to connect the safety loop and start the test. When one MCU fails to control the relay in time due to a random fault, the other MCU will cut off the relay output according to the feedback of the interactive information to keep the elevator in a safe state, ensuring the functional safety of the overall system.

[0095] The chip of the microcontroller minimum system module is selected as TMS570LC4357 of Texas Instruments. This chip itself has a lock-step dual ARM Cortex-R5F floating-point kernel, which can meet the requirements of the IEC 61508 SIL3 safety standard. It integrates 41-channel ADC interfaces, 5 MibSPI communication interfaces, 4 UART interfaces, up to 168 GPIO interfaces, as well as I2C communication and EMIF communication interfaces, which can meet the connection with the rest of the circuit. The two MCUs communicate in the MibSPI mode. According to the requirements of the PESSRAL circuit, when a random fault occurs in one of the two channels, the system will enter the safe state. In this paper, the main system sends a query request to the secondary MCU at the beginning and end of each cycle. Similarly, the secondary MCU waits for the MCU to send a query request at the beginning and end of each cycle. If the two pieces of information are inconsistent, or one MCU system falls into an infinite loop resulting in communication failure, the system is put into a safe state through the relay output. By the method of mutual real-time supervision between the two MCUs, the probability of random faults can be greatly reduced and the reliability can be improved.

[0096] To ensure reliability and safety, it is finally divided into three parts: the A and B core boards and the base board. The two identical A and B core boards are mainly composed of the microcontroller minimum module, the ADC input module and the storage module. The base board is composed of the rest of the parts. There are two groups of interfaces on the base board to realize the docking with the A and B core boards respectively.

[0097] The present invention solves the problems of identifying physical phenomena such as too small braking distance, too large air gap, friction plate wear, too low coil voltage, too low coil current, coil overheating, residual coil voltage and current, and insufficient spring force by using the encoder reading, brake gap, friction noise, brake voltage, brake current, coil temperature, and microswitch response time as the data objects collected by the monitoring system.

[0098] The present invention solves the control of the system power supply and ensures the safety of personnel and equipment by connecting the output switch of the monitoring system to the safety loop.

[0099] The present invention solves the problem that when a random fault occurs in one of the two channels, the system will enter the safe state by using the main and secondary dual systems to simultaneously complete the function of monitoring the operating state of the brake.

[0100] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0101] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Without conflict, the embodiments of the present application and the features in the embodiments can be arbitrarily combined with each other.

Claims

1. A real-time status monitoring and early warning system for an elevator brake, characterized in that, it includes: a traction machine, a brake, a sensor subsystem, a logic subsystem, and a final element subsystem; the sensor subsystem is connected to the logic subsystem; the logic subsystem is connected to the final element subsystem; the sensor subsystem includes: sensor components; the real-time status monitoring and early warning system for an elevator brake includes: an elevator system, an elevator brake, sensor components, an input module, a logic processing module, and an early warning and output module; the elevator system and the elevator brake are respectively connected to the sensor components; the input module is connected to the sensor components; the input module is connected to the logic processing module; the logic processing module is connected to the early warning and output module; the final element subsystem is connected to the brake; the final element subsystem can cut off the power supply of the brake in time when a fault or danger occurs; the sensor components include: an AC voltage sensor and an AC current sensor; the AC voltage sensor and the AC current sensor are respectively connected to the elevator system; the AC voltage sensor and the AC current sensor are respectively connected to the input module; the sensor components include: a displacement sensor, a temperature sensor, a DC voltage sensor, a DC current sensor, and a noise sensor; the displacement sensor, the temperature sensor, the DC voltage sensor, the DC current sensor, and the noise sensor are respectively connected to the elevator brake; the displacement sensor, the temperature sensor, the DC voltage sensor, the DC current sensor, and the noise sensor are respectively connected to the input module; the sensor subsystem also includes: a rotary encoder; the rotary encoder is connected to the elevator system; the rotary encoder is connected to the input module.

2. The real-time status monitoring and early warning system for an elevator brake according to claim 1, characterized in that, the sensor subsystem also includes: a microswitch; the microswitch is connected to the elevator brake; the microswitch is connected to the input module.

3. The real-time status monitoring and early warning system for an elevator brake according to claim 1, characterized in that, it further includes: a DC current transmitter and a perforated AC current transmitter; the AC voltage sensor, the AC current sensor, the DC voltage sensor, and the DC current sensor are connected in parallel to the positive and negative poles of the brake coil to monitor the brake coil voltage; the DC current transmitter is connected in series to the brake circuit to monitor the current; the perforated AC current transmitter monitors the output current of the traction machine.

4. The real-time status monitoring and early warning system for an elevator brake according to claim 1, characterized in that, the temperature sensor uses a J-type linear thermocouple.

5. The real-time status monitoring and early warning system for an elevator brake according to claim 1, characterized in that, the displacement sensor uses a laser displacement sensor.

6. The real-time status monitoring and early warning system for an elevator brake according to claim 1, characterized in that, the rotary encoder uses a Heidenhain absolute encoder.

7. The real-time status monitoring and early warning system for an elevator brake according to claim 1, characterized in that, The logic subsystem includes: an MCU component, a power supply module, a power supply monitoring module, a watchdog module, and a storage module.

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