Elevator drum brake monitoring device

Abstract

The present invention discloses an elevator drum brake monitoring device, which relates to the field of elevator brakes. The device comprises: a data acquisition module, a data processing module, a floor call box control module and a control module; the data acquisition module comprises a video acquisition camera and a current sensor; the video acquisition camera is used to acquire video images of the elevator drum brake and transmit the video images to the data processing module; the current sensor is used to acquire the brake coil current of the elevator drum brake; the control module is used to judge whether the response time of the brake action exceeds the response time threshold value and whether the displacement of the top of each brake arm exceeds the displacement threshold range of the top of the brake arm according to the data output by the data processing module and the current sensor, and if an abnormality occurs, the floor call box control module is used to cut off the floor call box circuit loop. The present invention reduces the impact on the safety performance of the elevator brake during the monitoring process.

Description

Technical Field

[0001] The invention relates to the technical field of elevator brakes, and in particular to an elevator drum brake monitoring device. Background Art

[0002] As the main means of transportation in buildings, elevators have become an indispensable part of people's daily lives. According to incomplete statistics, elevators in China transport more than 2 billion people every day. Elevators are closely related to the daily work and life of the public, and directly affect the personal safety and convenience of life of the people. Elevators in China have the characteristics of high frequency of use, long operating time, and complex use environment. In addition, elevators are "aging" year by year and are entering a period of frequent failures.

[0003] The brake is one of the important safety devices that are indispensable for elevators. Its main function is to achieve power-off braking when the elevator is leveled, ensuring the safety of passengers getting on and off the elevator. In addition, the brake integrates multiple safety functions such as upward overspeed protection and accidental car movement protection. Most elevator safety accidents are caused by brake failure, which can cause significant personal injury and property losses when serious problems occur.

[0004] For a long time, elevator brake tests before product finalization have been completed in the laboratories of type test institutions. Elevators installed in buildings are mostly tested indirectly through the car braking distance. According to the inspection requirements, the elevator is loaded with 125% of the rated load or no load, and the brake is manually de-energized to stop the running car. The braking performance of the brake is determined by the car braking distance. The method of using the car braking distance to characterize the braking performance has the following disadvantages: (1) The car braking distance is a comprehensive performance of the traction performance and the braking performance. It is unscientific to use it directly to characterize the brake performance. For example, if the stopping distance is too long, it may be that the braking performance is low, or it may be that the braking performance is too high (the wire rope and the traction wheel produce too much slip during emergency stopping); (2) A large number of weights need to be carried, which wastes manpower and affects the inspection efficiency; (3) Too much reliance on the experience of the inspectors for qualitative judgment leads to the risk of false detection and missed detection.

[0005] In response to the problem of elevator brake performance detection and monitoring, several inventions have proposed detection and monitoring devices by adding sensors. However, the way to add sensors is mostly by modifying the elevator brake (including brake arm, brake shoe, spring and brake coil, etc.), changing the elevator control circuit, and even intervening in the elevator safety circuit. The elevator brake is a key component with extremely high requirements for stable performance. The direct modification method cannot estimate the impact on the elevator safety performance. In the event of an accident, it will be implicated, and there is a huge risk of liability. In addition, changing the status of elevator brakes, control circuits, safety circuits and other components may also face a series of links such as elevator manufacturer verification, type testing, supervision inspection, regular inspection, functional safety certification, etc., which are difficult to operate in practice and difficult to apply in practice. In actual applications, micro switches are used to monitor the brake action status, but because of their unreliable operation and many faults, most of them have been removed or short-circuited by elevator maintenance units.

[0006] Currently, most newly manufactured elevators have brake performance monitoring functions through their underlying electromechanical design. However, it is difficult to monitor the brake performance of old elevators that occupy the vast majority of the market using the monitoring methods of new elevators.

[0007] Most of the old elevators are of the drum brake type. Therefore, it is necessary to develop a non-contact monitoring device and method for elevator drum brakes that does not modify the elevator brakes, does not change the elevator control circuit, and does not interfere with the safety circuit. Summary of the invention

[0008] The purpose of the present invention is to provide an elevator drum brake monitoring device, which does not require the modification of the elevator brake, does not change the elevator control circuit, does not interfere with the elevator safety circuit, and reduces the impact on the safety performance of the elevator brake.

[0009] To achieve the above object, the present invention provides the following solutions:

[0010] An elevator drum brake monitoring device comprises: a data acquisition module, a data processing module, a landing call box control module and a control module; the data acquisition module is connected to the data processing module, the data processing module is connected to the landing call box control module and both are connected to the control module;

[0011] The data acquisition module includes a video acquisition camera and a current sensor;

[0012] The video acquisition camera is used to acquire video images of the elevator drum brake and transmit the video images to the data processing module;

[0013] The data processing module is used to set the tops of the two brake arms as regions of interest, determine the instantaneous displacement of the tops of the two brake arms in two adjacent video images based on the edge shape tracking method, determine the starting brake state, the brake holding state, the starting brake release state and the brake holding release state of the brake arms according to the instantaneous displacement of the tops of the two brake arms in the two adjacent video images, and send the corresponding times of the starting brake state, the brake holding state, the starting brake release state and the brake holding release state to the control module;

[0014] The current sensor is used to collect the brake coil current of the elevator drum brake and send the brake coil current to the control module;

[0015] The control module is used to determine the time when the brake coil starts to be energized according to the brake coil current, and determine the response time of the brake action according to the time when the brake coil starts to be energized and the time corresponding to the start of the brake state. If the response time of the brake action exceeds the response time threshold, an alarm signal of abnormal brake action response time is sent to the landing call box control module;

[0016] The data processing module is also used to determine the displacement of the top end of each brake arm according to the video image corresponding to the brake start state and the video image corresponding to the brake hold state;

[0017] The control module is also used to determine whether the displacement of the top end of each brake arm exceeds the brake arm top end displacement threshold range, and if it exceeds the brake arm top end displacement threshold range, send a brake holding clearance abnormality alarm signal to the landing call box control module;

[0018] The landing call box control module is used to cut off the landing call box circuit loop when receiving an abnormal situation alarm signal.

[0019] Optionally, an infrared camera is also included;

[0020] The infrared camera is used to obtain an infrared image of the brake shoe on the elevator drum brake;

[0021] The data processing module is further used to determine the temperature of the brake shoe according to the infrared image, and send the temperature of the brake shoe to the control module;

[0022] The control module is also used to send a brake temperature abnormality alarm signal to the landing call box control module when the temperature of the brake shoe is higher than a temperature threshold;

[0023] The control module is also used to obtain the average temperature of the brake shoe in the most recent set time period, recorded as the first temperature average value, and to obtain the average temperature of the brake shoe in a set time period before the most recent set time period, recorded as the second temperature average value; if the first temperature average value is higher than the second temperature average value by a first percentage, an abnormal brake temperature alarm signal is sent to the floor station call box control module.

[0024] Optionally, a noise sensor is also included;

[0025] The noise sensor is used to collect noise signals within a set range of the elevator drum brake and send the noise signals to the controller module;

[0026] The control module is used to send a brake noise abnormality alarm signal to the landing call box control module when the intensity of the noise signal is greater than the sound intensity threshold;

[0027] The control module is also used to obtain the average intensity of the noise signal in the most recent set time period, recorded as a first intensity average, and to obtain the average intensity of the noise signal in a set time period before the most recent set time period, recorded as a second intensity average; if the first intensity average is higher than the second intensity average by a second percentage, an abnormal brake noise alarm signal is sent to the floor station call box control module.

[0028] Optionally, the control module is also used to obtain the average value of the displacement of the top of each brake arm in the most recent set time period, and the average value of the displacement of the top of each brake arm in a set time period before the most recent set time period. If the average value of the displacement of the top of the brake arm in the most recent set time period and the average value of the displacement of the top of the corresponding brake arm in a set time period before the most recent set time period are higher than a third percentage, or lower than a fourth percentage, an alarm signal of abnormal brake action response time is sent to the layer station call box control module.

[0029] Optionally, the control module is also used to obtain the average value of the response time of the brake action in the most recent set time period, recorded as the first response time average value, and obtain the average value of the response time of the brake action in a set time period before the most recent set time period, recorded as the second response time average value. If the first response time average value is higher than the second response time average value by the fifth percentage, an abnormal brake action response time alarm signal is sent to the layer station call box control module.

[0030] Optionally, the data processing module is further used to determine the rotation angle of the brake wheel based on the texture direction of the frequency spectrum of the video image, and send the rotation angle and the time corresponding to the rotation angle to the control module;

[0031] The control module is also used to determine the rotation angle when the brake wheel stops rotating according to the rotation angle when the brake arm is in a holding brake state and the time corresponding to the rotation angle, and determine the braking distance of the traction main machine according to the rotation angle when the brake wheel stops rotating and the traction wheel diameter, and when the braking distance exceeds the braking distance threshold range, send a braking distance abnormality alarm signal to the landing call box control module;

[0032] The control module is also used to obtain the average value of the braking distance in the most recent set time period, recorded as the first braking distance average value, and obtain the average value of the braking distance in a set time period before the most recent set time period, recorded as the second braking distance average value. If the first braking distance average value is higher than the second braking distance average value by the sixth percentage, an abnormal brake action response time alarm signal is sent to the layer station call box control module.

[0033] Optionally, the control module is further used for:

[0034] According to the change of the rotation angle of the brake wheel over time, the first-order derivative, the second-order derivative, and the third-order derivative are performed to obtain the angular velocity, angular acceleration, and angular acceleration of the brake wheel respectively;

[0035] The elevator running speed is determined according to the angular velocity of the brake wheel and the diameter of the traction wheel. If the elevator running speed exceeds the rated speed range of the elevator, an abnormal elevator running speed alarm signal is sent to the landing call box control module;

[0036] The elevator running acceleration is determined according to the angular acceleration of the brake wheel and the diameter of the traction wheel. If the elevator running acceleration is greater than the set acceleration, an abnormal elevator running acceleration alarm signal is sent to the landing call box control module;

[0037] The variable acceleration of the elevator operation is determined according to the angular variable acceleration of the brake wheel and the diameter of the traction wheel, and the slope of the variable acceleration of the elevator operation is calculated. If the slope of the variable acceleration of the elevator operation is greater than the slope threshold, an abnormal alarm signal of the elevator operation stability is sent to the floor station call box control module.

[0038] Optionally, it further comprises a terminal application, the terminal application is connected to the control module, and the terminal application is used to input the elevator rated speed, the traction wheel diameter, the brake arm top displacement threshold, the slope threshold, the sound intensity threshold and the temperature threshold;

[0039] The terminal application is also used to receive abnormal situation alarm signals and display them.

[0040] Optionally, the terminal application is connected to the control module via Bluetooth, and the control module includes an ARM main chip circuit.

[0041] Optionally, the set time period is 24 hours.

[0042] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0043] The present invention dynamically collects video images of the elevator drum brake through a video acquisition camera, and collects the brake coil current of the elevator drum brake through a current sensor, thereby monitoring the response time of the brake action and the brake clearance, realizing non-contact detection of the elevator drum brake, and reducing the impact on the safety performance of the elevator brake. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0045] Figure 1 This is a structural schematic diagram of an elevator drum brake monitoring device of the present invention;

[0046] Figure 2 This is a structural block diagram of an elevator drum brake monitoring device of the present invention;

[0047] Figure 3 It is a schematic diagram of the top portion of the brake arm in the elevator drum brake of the present invention;

[0048] Explanation of symbols:

[0049] Brake arm—1, brake arm top—2, brake wheel—3. DETAILED DESCRIPTION

[0050] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] The purpose of the present invention is to provide an elevator drum brake monitoring device, which does not require the modification of the elevator brake, does not change the elevator control circuit, does not interfere with the elevator safety circuit, and reduces the impact on the safety performance of the elevator brake.

[0052] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0053] Example 1

[0054] like Figure 1 As shown, an elevator drum brake monitoring device of the present invention includes: a data acquisition module 101, a data processing module 102, a floor call box control module 103 and a control module 104; the data acquisition module 101 is connected to the data processing module 102, and the data processing module 102 is connected to the floor call box control module 103 and is connected to the control module 104.

[0055] The data acquisition module 101 includes a video acquisition camera and a current sensor.

[0056] like Figure 2 As shown, the data processing module 102 includes a video acquisition camera processing system, an infrared camera processing system, a noise signal acquisition card and a current signal acquisition card.

[0057] The control module 104 includes an ARM main chip circuit, a power supply and a Bluetooth wireless data transmission unit.

[0058] The landing call box control module 103 includes a relay and a landing call box control circuit.

[0059] The elevator drum brake monitoring device of the present invention also includes a terminal application program, namely an Internet-based APP105, which is used for display interface, operation interface and abnormal situation alarm.

[0060] The terminal application is also used to receive abnormal situation alarm signals and display them.

[0061] The terminal application is connected to the control module 104 via Bluetooth, and the control module 104 includes an ARM main chip circuit.

[0062] The ARM main chip circuit is connected to the Bluetooth wireless data transmission unit, and the Bluetooth wireless data transmission unit is connected to the Internet-based APP105.

[0063] The power supply supplies power to the ARM main chip circuit and the Bluetooth wireless data transmission unit.

[0064] The video image of the brake is collected by the video acquisition camera and transmitted to the video acquisition camera processing system. The video acquisition camera is used to track the movement of the brake arm.

[0065] The video acquisition camera is used to acquire video images of the elevator drum brake and transmit the video images to the data processing module 102 .

[0066] The video acquisition camera processing system is used to set the top ends of the two brake arms as regions of interest (ROIs), determine the instantaneous displacement of the top ends of the two brake arms in two adjacent video images based on the edge shape tracking method, determine the starting braking state, maintaining the braking state, starting the brake release state and maintaining the brake release state of the brake arms according to the instantaneous displacement of the top ends of the two brake arms in the two adjacent video images, and send the corresponding times of the starting braking state, maintaining the braking state, starting the brake release state and maintaining the brake release state to the control module 104.

[0067] The present invention determines the relationship between each pixel and the actual distance, and converts the pixel displacement of the top of the brake arm into the actual displacement of the top of the brake arm.

[0068] like Figure 3 As shown, the two brake arms 1 are the left brake arm and the right brake arm respectively. Since the structure of the top 2 of the brake arm can be regarded as a rigid structure during the monitoring process, the structural shape of the top of the brake arm can be regarded as unchanged during the image acquisition process, and the top of the brake arm is the set area of ​​the top of the brake arm, the edge shape tracking method is used to extract the positions of the tops of the two brake arms in the video image. First, the image inside the ROI is preprocessed by graphics to reduce the influence of image background factors; then the sub-pixel edge detection technology is used to detect the shape of the top of the brake arm in the ROI to obtain a two-dimensional quadrilateral target feature, and then the quadrilateral correlation in the same ROI area is calculated in the continuous frame image, and then the correlation measurement is used for graphic matching. The distance between the matching points is the distance of the tracked target in the two consecutive images. Using the above method in the two ROIs at the same time, the pixel displacement of the change of the top of the two brake arms can be calculated, and the pixel displacement can be converted into actual displacement by combining the scale factor. Image acquisition is dynamic and has "jitter" phenomenon, so it is necessary to set the instantaneous displacement threshold. When the instantaneous displacement threshold is exceeded, it is considered that the brake arm starts to move; when the instantaneous displacement is lower than the instantaneous displacement threshold, it is considered that the brake arm starts to stop, and the start of movement and the start of stop are recorded. The top of the brake arm is horizontal and lateral reciprocating motion. In the collected video image, the displacement moving to the right is a positive value, and the displacement moving to the left is a negative value, which determines the movement direction of the two brake arms. Figure 3 3 in the middle is a brake wheel.

[0069] The present invention specifically comprises the following steps to determine the displacement of the brake arm:

[0070] Step 1: Set up the camera in front of the brake axis and adjust the camera image to focus. Fix the camera position and focal length.

[0071] Step 2: Calibrate the camera (video acquisition camera). First, use the checkerboard calibration method to calibrate the camera's internal parameters, and then use the scale factor method to obtain the relationship between pixel distance and actual distance.

[0072] Step 3: Select the region of interest (RIO). Since the movement of the two brake arms needs to be tracked simultaneously, two regions of interest need to be defined in the image.

[0073] Step 4: The present invention obtains the region of interest (top of the brake arm) in the captured video image based on an edge shape tracking method, and performs target tracking on the top of the brake arm. Since the brake arm can be regarded as a rigid structure in this measurement, the structural shape within the brake arm image ROI can be regarded as unchanged during the image acquisition process. Therefore, the image inside the ROI is first preprocessed by graphics to reduce the influence of image background factors. Then, the shape of the brake arm in the ROI is detected using sub-pixel edge detection technology. In this way, a two-dimensional quadrilateral target feature can be obtained. Then, the correlation of the quadrilaterals in the same ROI area is calculated in consecutive frame images, and then the correlation metric is used for graphic matching. The distance between the matching points is the distance of the tracked target in two consecutive images.

[0074] Step 4: Use the above method in both ROIs to calculate the pixel displacement of the two brake arms. Combined with the scale factor, the pixel displacement is converted into the actual displacement. Draw the time domain waveform of the actual displacement.

[0075] Step 5: Set a displacement threshold. Once the displacement exceeds the threshold, the brake arm is considered to have started to move. Note the start time so that the start time of the two brake arms can be compared.

[0076] In the captured video image, the displacement of the top ends of the two brake arms is higher than the instantaneous displacement threshold (i.e., the start of movement). In the next step, when the instantaneous displacement of the top end of the left brake arm is a positive value and the instantaneous displacement of the top end of the right brake arm is a negative value (i.e., braking action), the brake arms are considered to be in the starting braking state.

[0077] According to the collected video images, the instantaneous displacement of the top of the left brake arm is a positive value, and the instantaneous displacement of the top of the right brake arm is a negative value (i.e., braking action). In the next step, when the instantaneous displacement of the top of the two brake arms is lower than the instantaneous displacement threshold (i.e., the beginning of stationary state), the brake arms are considered to be in a braking state.

[0078] According to the collected video images, the displacement of the top ends of the two brake arms is higher than the instantaneous displacement threshold (i.e., the start of movement). In the next step, when the instantaneous displacement of the top end of the left brake arm is a negative value and the instantaneous displacement of the top end of the right brake arm is a positive value (i.e., the release action), the brake arm is considered to be in the state of starting to release.

[0079] According to the collected video images, the instantaneous displacement of the top of the left brake arm is a negative value, and the instantaneous displacement of the top of the right brake arm is a positive value (i.e., the brake is released). In the next step, when the instantaneous displacement of the top of the two brake arms is lower than the instantaneous displacement threshold (i.e., the beginning of stillness), the brake arms are considered to be in a released state.

[0080] The video acquisition camera processing system is also used to determine the displacement of the top end of each brake arm according to the video image corresponding to the brake start state and the video image corresponding to the brake hold state.

[0081] For example, the displacement of the top end of the left brake arm is the distance between the position of the top end of the left brake arm in the video image corresponding to the start brake state and the position of the top end of the left brake arm in the video image corresponding to the maintain brake state.

[0082] The control module 104 is also used to determine whether the displacement of the top of each brake arm exceeds the brake arm top displacement threshold range. If it exceeds the brake arm top displacement threshold range, it sends a brake clearance abnormality alarm signal to the landing call box control module 103.

[0083] The brake arm top end displacement threshold range is a range of ±20% of the brake arm top end displacement threshold.

[0084] The control module 104 is also used to obtain the average value of the displacement of the top of each brake arm in the most recent set time period, and the average value of the displacement of the top of each brake arm in a set time period before the most recent set time period. If the average value of the displacement of the top of the brake arm in the most recent set time period and the average value of the displacement of the top of the corresponding brake arm in a set time period before the most recent set time period are higher than the third percentage, or lower than the fourth percentage, an alarm signal of abnormal brake action response time is sent to the floor station call box control module 103.

[0085] As a specific implementation, the third percentage is 120%, and the fourth percentage is 80%. If the average displacement of the top of the brake arm in the past 24 hours is higher than 120% or lower than 80% of the average displacement of the top of the brake arm in the previous 24 hours, an abnormal brake action response time alarm signal will be issued.

[0086] The current sensor is used to collect the brake coil current of the elevator drum brake and send the brake coil current to the control module 104.

[0087] The current sensor is connected to the current signal acquisition card, which is connected to the ARM main chip circuit. The current signal acquisition card modulates the output current signal to the ARM main chip circuit. The current sensor is a clamp-type current sensor. There are 4 current sensors, 2 of which are clamped in the two brake coil power supply circuits, 1 is clamped in the output end of the host inverter, and 1 is clamped in the circuit loop of the floor station call box to monitor the presence or absence of current.

[0088] The control module 104 is used to determine the time when the brake coil starts to be energized according to the brake coil current, and determine the response time of the braking action according to the time when the brake coil starts to be energized and the time corresponding to the start of the braking state. If the response time of the braking action exceeds the response time threshold, an alarm signal of abnormal brake action response time is sent to the layer station call box control module 103.

[0089] The response time threshold is 0.5s.

[0090] The control module 104 is also used to obtain the average value of the response time of the brake action in the most recent set time period, recorded as the first response time average value, and obtain the average value of the response time of the brake action in a set time period before the most recent set time period, recorded as the second response time average value. If the first response time average value is higher than the second response time average value by the fifth percentage, an abnormal brake action response time alarm signal is sent to the layer station call box control module 103.

[0091] The fifth percentage is 120%.

[0092] The floor call box control module 103 is used to cut off the circuit loop of the 5th floor call box when receiving an abnormal situation alarm signal.

[0093] The elevator drum brake monitoring device of the present invention also includes an infrared camera.

[0094] The infrared camera is used to obtain an infrared image of the brake shoe on the elevator drum brake. The infrared camera specifically obtains the temperature of the brake shoe on both sides.

[0095] The infrared camera processing system is further configured to determine the zero temperature of the brake shoe according to the infrared image, and send the temperature of the brake shoe to the control module 104 .

[0096] The infrared camera processing system outputs a maximum temperature data signal to the control module 104 .

[0097] The infrared camera is connected to the infrared camera processing system, and the infrared camera processing system is connected to the ARM main chip circuit, outputting the temperature signal to the ARM main chip circuit.

[0098] The control module 104 is also used to send a brake temperature abnormality alarm signal to the landing call box control module 103 when the temperature of the brake shoe is higher than a temperature threshold.

[0099] The control module 104 is further configured to obtain an average temperature of the brake shoe in a recent set time period, recorded as a first average temperature, and obtain an average temperature of the brake shoe in a set time period before the recent set time period, recorded as a second average temperature; if the first average temperature

[0100] If the temperature is higher than the second temperature average value by a first percentage, an abnormal brake temperature alarm signal is sent to the landing call box control module 103.

[0101] The set time period is 24 hours.

[0102] As a specific implementation, the first percentage is 120%, and if the average maximum brake temperature in the past 24 hours is higher than 120% of the average maximum brake temperature in the previous 24 hours, an abnormal brake temperature alarm will be issued. The maximum temperature of the brake shoe is collected by an infrared camera.

[0103] The elevator drum brake monitoring device of the present invention further comprises a noise sensor.

[0104] When the brake fails, it often makes abnormal noise. The noise sensor is installed 1m away from the brake to obtain the sound intensity each time the brake is actuated. The sound intensity signal is output to the ARM main chip circuit through the noise data acquisition card. The sound intensity threshold is set to determine whether the noise is normal. If the sound intensity threshold is exceeded, an abnormal brake action noise alarm will be issued.

[0105] The noise sensor is used to collect noise signals within a set range of the elevator drum brake and send the noise signals to the controller module.

[0106] The noise sensor is connected to the noise signal acquisition card, the noise signal acquisition card is connected to the ARM main chip circuit, and outputs the noise signal to the ARM main chip circuit.

[0107] The control module 104 is used for sending a brake noise abnormality alarm signal to the landing call box control module 103 when the intensity of the noise signal is greater than a sound intensity threshold.

[0108] When the elevator speed is less than or equal to 2.5 m / s, the sound intensity threshold is 80 dB (A); when the elevator speed is less than 6.0 m / s and greater than 2.5 m / s, the sound intensity threshold is 85 dB (A); when the elevator speed is greater than or equal to 6.0 m / s, the sound intensity threshold is set according to the manufacturer's regulations through the Internet-based APP105.

[0109] The control module 104 is also used to obtain the average intensity of the noise signal in the most recent set time period, recorded as the first intensity average, and to obtain the average intensity of the noise signal in the set time period before the most recent set time period, recorded as the second intensity average; if the first intensity average is higher than the second intensity average by a second percentage, an abnormal brake noise alarm signal is sent to the floor station call box control module 103.

[0110] The second percentage is 120%.

[0111] The data processing module 102 is also used to determine the rotation angle of the brake wheel based on the texture direction of the spectrum diagram of the video image, and send the rotation angle and the time corresponding to the rotation angle to the control module 104, more specifically including performing Fourier spectrum analysis on the video image to obtain the spectrum diagram.

[0112] The present invention determines the time corresponding to when the brake arm maintains the brake state and determines the rotation angle of the brake wheel at this time, further determines the time when the brake wheel stops rotating and determines the rotation angle of the brake wheel at this time, and then calculates the braking distance of the traction main machine according to the input traction wheel diameter.

[0113] The control module 104 is also used to determine the rotation angle when the brake wheel stops rotating according to the rotation angle when the brake arm is in a holding state and the time corresponding to the rotation angle, and determine the braking distance of the traction main machine according to the rotation angle when the brake wheel stops rotating and the traction wheel diameter, and when the braking distance exceeds the braking distance threshold range, send a braking distance abnormality alarm signal to the layer station call box control module 103.

[0114] The control module 104 is also used to obtain the average value of the braking distance in the most recent set time period, recorded as the first braking distance average value, and obtain the average value of the braking distance in a set time period before the most recent set time period, recorded as the second braking distance average value. If the first braking distance average value is higher than the second braking distance average value by the sixth percentage, an abnormal brake action response time alarm signal is sent to the layer station call box control module 103.

[0115] As a specific implementation, the sixth percentage is 120%. Through analysis of historical braking distance data, if the average braking distance in the past 24 hours is higher than 120% of the average braking distance in the previous 24 hours, an abnormal braking distance alarm will also be issued.

[0116] The control module 104 is also used for:

[0117] According to the change of the rotation angle of the brake wheel with time, the first-order derivative, the second-order derivative and the third-order derivative are performed to obtain the angular velocity, angular acceleration and angular acceleration of the brake wheel respectively.

[0118] The elevator running speed is determined according to the angular velocity of the brake wheel and the diameter of the traction wheel. If the elevator running speed exceeds the rated speed range of the elevator, an abnormal elevator running speed alarm signal is sent to the landing call box control module 103.

[0119] The rated speed range of the elevator is ±10% of the rated speed of the elevator.

[0120] As a specific implementation, when the normal operating speed exceeds the rated speed by ±10%, an abnormal elevator speed alarm is issued. The elevator running acceleration is calculated based on the brake wheel angular acceleration combined with the traction wheel diameter. When the maximum value of the starting acceleration / braking deceleration is greater than 1.5m / s 2 When the elevator is running at an abnormal acceleration, an alarm is issued. The elevator running acceleration is calculated based on the brake wheel angular acceleration and the traction wheel diameter, and the stability of the start / brake process is judged and analyzed. The slope threshold of the variable acceleration line that meets the stability of the elevator model is set, and the actual variable acceleration line slope is solved. If the absolute value of the slope exceeds the threshold, an alarm is issued for abnormal elevator running stability.

[0121] The elevator running acceleration is determined according to the angular acceleration of the brake wheel and the traction wheel diameter. If the elevator running acceleration is greater than the set acceleration, an abnormal elevator running acceleration alarm signal is sent to the landing call box control module 103.

[0122] The elevator running variable acceleration is determined according to the angular variable acceleration of the brake wheel and the traction wheel diameter, and the slope of the elevator running variable acceleration is calculated. If the slope of the elevator running variable acceleration is greater than the slope threshold, an abnormal alarm signal of the elevator running stability is sent to the floor station call box control module 103.

[0123] The terminal application is connected to the control module 104, and the terminal application is used to input parameters such as the elevator rated speed, traction wheel diameter, brake arm top displacement threshold, slope threshold, sound intensity threshold, temperature threshold monitoring delay time and basic elevator parameters, and display the status of the monitored parts in real time. In case of abnormal conditions of parameters such as brake clearance, brake action response time, braking distance, elevator running speed, elevator running acceleration, elevator running stability, brake temperature, brake noise, etc., the abnormal signal is transmitted to the APP for real-time display, and an abnormal alarm is issued.

[0124] The ARM main chip circuit is also connected to the floor call box control module 103. All abnormal situation alarm signals are transmitted by the ARM main chip circuit to the Internet-based APP 105 for display, and the abnormal signal is transmitted to the floor call box control module 103 to cut off the floor call box circuit loop.

[0125] The floor call box control module 103 is a relay connected in series to the floor call box circuit loop. When the ARM main chip circuit detects an abnormal signal, the ARM main chip circuit will output a disconnection command to the floor call box control module 103, and the floor call box circuit loop will be disconnected. However, this behavior does not affect the operation of the elevator at that time. After the elevator completes the task it is performing and closes the floor door and car door, the elevator floor call box device loses its function, and external personnel cannot select floors to control the elevator, avoiding the state of the elevator running with a fault.

[0126] The installation of the floor call box control module 103 does not involve changing the elevator control circuit or connecting to the safety circuit. It is considered general maintenance according to national regulations and can be carried out by elevator maintenance personnel without the need for supervisory inspection, regular inspection, functional safety certification, etc.

[0127] The monitoring device of the present invention uses non-contact methods such as received video images, sounds, infrared, induced current, etc. to monitor the brake.

[0128] When there is a problem with the elevator brake, the main manifestations are the car slipping, hitting the top, hitting the bottom of the equipment, and the poor comfort and abnormal noise experienced by the personnel.

[0129] Since elevator brake accidents almost all occur during the brake action phase, the elevator drum brake non-contact monitoring method is also characterized in that it mainly monitors the brake action process without the need to monitor the brake conditions when the elevator is running / stationary.

[0130] When the elevator brake is powered on and released, when the monitoring device of the present invention detects the presence of any current in the floor call box circuit loop current, the brake coil current, and the inverter output current, the device starts to monitor the brake; when the ARM main chip circuit detects the hold-release signal output by the video acquisition camera processing system, the video acquisition camera stops working, and a delay of 5s after the start of monitoring is set to force the monitoring to stop.

[0131] When the elevator brake is in the process of power-off braking, when the device of the present invention detects that any current in the brake double-side coil current and the inverter output current disappears, the device starts to monitor the brake; when the ARM main chip circuit detects the holding brake signal output by the video acquisition camera processing system, the video acquisition camera stops working, and a delay of 5s after the start of monitoring is set to force the monitoring to stop.

[0132] Embodiment 2:

[0133] This embodiment is when the elevator is running normally: someone presses the landing call button, and the monitoring device detects the current of the landing call circuit and starts the entire device. The video acquisition camera, infrared camera, noise sensor, current sensor, etc. in the device start to collect brake-related signals. Then the elevator control system opens the elevator brake and runs the traction host. When the monitoring device detects the brake release signal and the main control system determines that there is no abnormality, the monitoring device stops monitoring.

[0134] When the elevator arrives at the destination floor, the monitoring device detects that the current on both sides of the elevator brake coil disappears, and then starts the entire device. The video acquisition camera, infrared camera, noise sensor, current sensor, etc. in the device begin to collect brake-related signals. Then the elevator control system closes the elevator brake and stops the main engine. When the monitoring device detects the brake release signal and the main control system determines that there is no abnormality, the monitoring device stops monitoring.

[0135] Embodiment 3:

[0136] This embodiment is an abnormal braking distance of the traction main machine: when the elevator arrives at the landing station, the video acquisition camera, infrared camera, noise sensor, current sensor, etc. in the monitoring device begin to collect brake-related signals. When the braking distance of the traction main machine is abnormal, the monitoring device receives the rotation angle of the brake wheel and its corresponding time, the brake holding time and other signals, determines the time corresponding to the brake wheel holding the brake state and determines the rotation angle of the brake wheel at this time, further determines the time when the brake wheel stops rotating and determines the rotation angle of the brake wheel at this time, and then calculates the braking distance according to the traction wheel diameter to exceed the threshold range, and determines that the braking distance of the traction main machine is abnormal. In addition, the monitoring device also analyzes the historical braking distance data. If the average braking distance of the past 24 hours is higher than 120% of the average braking distance of the previous 24 hours, it will also determine that the braking distance of the traction main machine is abnormal. The monitoring device detects the abnormal state, displays the abnormal alarm through the Internet APP, and disconnects the circuit loop of the landing call box in time. The elevator landing call box device loses its function, and passengers outside the elevator cannot operate the elevator, preventing the next operation of the elevator, but the people inside the elevator can still reach the corresponding floor and leave.

[0137] The present invention uses video images, infrared, noise, induced current and other technologies to monitor the elevator brake, thereby realizing non-contact monitoring of the elevator brake. The present invention does not require modification of the elevator brake, does not change the elevator control circuit, does not interfere with the elevator safety circuit, etc., does not affect the safety performance of the elevator brake, and avoids liability risks.

[0138] The present invention does not require the use of high-value, high-sampling-frequency industrial cameras for precise positioning, and dynamically monitors the brake status by comparing and analyzing the historical data of the monitored brake and the data of the same group.

[0139] The present invention timely cuts off the circuit of the floor call box device when an abnormal situation is found, and passengers outside the elevator cannot operate the elevator, preventing the elevator from running next time, but people inside the elevator can still reach the corresponding floor and leave. Cutting off the circuit of the floor call box device is a general repair, and does not require elevator manufacturer verification, supervision inspection, functional safety certification, etc.

[0140] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0141] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the device and its core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. An elevator drum brake monitoring device, characterized in that: include: Data acquisition module, data processing module, landing call box control module and control module; the data acquisition module is connected to the data processing module, the data processing module is connected to the landing call box control module and both are connected to the control module; The data acquisition module includes a video acquisition camera and a current sensor; The video acquisition camera is used to acquire video images of the elevator drum brake and transmit the video images to the data processing module; The data processing module is used to set the tops of the two brake arms as regions of interest, determine the instantaneous displacement of the tops of the two brake arms in two adjacent video images based on the edge shape tracking method, determine the starting brake state, the brake holding state, the starting brake release state and the brake holding release state of the brake arms according to the instantaneous displacement of the tops of the two brake arms in the two adjacent video images, and send the corresponding times of the starting brake state, the brake holding state, the starting brake release state and the brake holding release state to the control module; The current sensor is used to collect the brake coil current of the elevator drum brake and send the brake coil current to the control module; The control module is used to determine the time when the brake coil starts to be energized according to the brake coil current, and determine the response time of the brake action according to the time when the brake coil starts to be energized and the time corresponding to the start of the brake state. If the response time of the brake action exceeds the response time threshold, an alarm signal of abnormal brake action response time is sent to the landing call box control module; The data processing module is also used to determine the displacement of the top end of each brake arm according to the video image corresponding to the brake start state and the video image corresponding to the brake hold state; The control module is also used to determine whether the displacement of the top end of each brake arm exceeds the brake arm top end displacement threshold range, and if it exceeds the brake arm top end displacement threshold range, send a brake holding clearance abnormality alarm signal to the landing call box control module; The landing call box control module is used to cut off the landing call box circuit loop when receiving an abnormal situation alarm signal.

2. The elevator drum brake monitoring device according to claim 1, characterized in that: Also includes an infrared camera; The infrared camera is used to obtain an infrared image of the brake shoe on the elevator drum brake; The data processing module is further used to determine the temperature of the brake shoe according to the infrared image, and send the temperature of the brake shoe to the control module; The control module is also used to send a brake temperature abnormality alarm signal to the landing call box control module when the temperature of the brake shoe is higher than a temperature threshold; The control module is also used to obtain the average temperature of the brake shoe in the most recent set time period, recorded as the first temperature average value, and to obtain the average temperature of the brake shoe in a set time period before the most recent set time period, recorded as the second temperature average value; if the first temperature average value is higher than the second temperature average value by a first percentage, an abnormal brake temperature alarm signal is sent to the floor station call box control module.

3. The elevator drum brake monitoring device according to claim 1, characterized in that: Also included is a noise sensor; The noise sensor is used to collect noise signals within a set range of the elevator drum brake and send the noise signals to the control module; The control module is used to send a brake noise abnormality alarm signal to the landing call box control module when the intensity of the noise signal is greater than the sound intensity threshold; The control module is also used to obtain the average intensity of the noise signal in the most recent set time period, recorded as a first intensity average, and to obtain the average intensity of the noise signal in a set time period before the most recent set time period, recorded as a second intensity average; if the first intensity average is higher than the second intensity average by a second percentage, an abnormal brake noise alarm signal is sent to the floor station call box control module.

4. The elevator drum brake monitoring device according to claim 1, characterized in that: The control module is also used to obtain the average value of the displacement of the top of each brake arm in the most recent set time period, and the average value of the displacement of the top of each brake arm in a set time period before the most recent set time period. If the average value of the displacement of the top of the brake arm in the most recent set time period and the average value of the displacement of the top of the corresponding brake arm in a set time period before the most recent set time period are higher than the third percentage, or lower than the fourth percentage, an alarm signal of abnormal brake action response time is sent to the floor station call box control module.

5. The elevator drum brake monitoring device according to claim 1, characterized in that: The control module is also used to obtain the average value of the response time of the brake action in the most recent set time period, recorded as the first response time average value, and obtain the average value of the response time of the brake action in a set time period before the most recent set time period, recorded as the second response time average value. If the first response time average value is higher than the second response time average value by the fifth percentage, an abnormal brake action response time alarm signal is sent to the layer station call box control module.

6. The elevator drum brake monitoring device according to claim 1, characterized in that: The data processing module is also used to determine the rotation angle of the brake wheel based on the texture direction of the frequency spectrum of the video image, and send the rotation angle and the time corresponding to the rotation angle to the control module; The control module is also used to determine the rotation angle when the brake wheel stops rotating according to the rotation angle when the brake arm is in a holding brake state and the time corresponding to the rotation angle, and determine the braking distance of the traction main machine according to the rotation angle when the brake wheel stops rotating and the traction wheel diameter, and when the braking distance exceeds the braking distance threshold range, send a braking distance abnormality alarm signal to the landing call box control module; The control module is also used to obtain the average value of the braking distance in the most recent set time period, recorded as the first braking distance average value, and obtain the average value of the braking distance in a set time period before the most recent set time period, recorded as the second braking distance average value. If the first braking distance average value is higher than the second braking distance average value by the sixth percentage, an abnormal brake action response time alarm signal is sent to the layer station call box control module.

7. The elevator drum brake monitoring device according to claim 6, characterized in that: The control module is also used for: According to the change of the rotation angle of the brake wheel over time, the first-order derivative, the second-order derivative, and the third-order derivative are performed to obtain the angular velocity, angular acceleration, and angular acceleration of the brake wheel respectively; The elevator running speed is determined according to the angular velocity of the brake wheel and the diameter of the traction wheel. If the elevator running speed exceeds the rated speed range of the elevator, an abnormal elevator running speed alarm signal is sent to the landing call box control module; The elevator running acceleration is determined according to the angular acceleration of the brake wheel and the diameter of the traction wheel. If the elevator running acceleration is greater than the set acceleration, an abnormal elevator running acceleration alarm signal is sent to the landing call box control module; The variable acceleration of the elevator operation is determined according to the angular variable acceleration of the brake wheel and the diameter of the traction wheel, and the slope of the variable acceleration of the elevator operation is calculated. If the slope of the variable acceleration of the elevator operation is greater than the slope threshold, an abnormal alarm signal of the elevator operation stability is sent to the floor station call box control module.

8. The elevator drum brake monitoring device according to claim 1, characterized in that: Also included is a terminal application, the terminal application is connected to the control module, the terminal application is used to input the elevator rated speed, traction sheave diameter, brake arm top displacement threshold, slope threshold, sound intensity threshold and temperature threshold; The terminal application is also used to receive abnormal situation alarm signals and display them.

9. The elevator drum brake monitoring device according to claim 8, characterized in that: The terminal application is connected to the control module via Bluetooth, and the control module includes an ARM main chip circuit.

10. The elevator drum brake monitoring device according to claim 2, characterized in that: The set time period is 24 hours.

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