Escalator brake anti-lock system and working method thereof

Abstract

This application discloses an escalator anti-lock braking system and its operating method. The escalator anti-lock braking system includes a brake wheel, a braking mechanism, a closing spring, a brake coil, a variable resistance mechanism, an energy storage capacitor, a step speed sensor, and a controller. This application utilizes the brake coil to generate a repulsive magnetic force on the brake arm, thereby reducing the instantaneous braking force of the brake shoes on the brake wheel during braking, resulting in more uniform and smooth braking. The magnetic force of the brake coil can be adjusted by the controller, allowing for automatic adjustment based on actual conditions.

Description

Technical Field

[0001] This application relates to an escalator braking anti-lock braking system and its working method in the field of escalator technology. Background Technology

[0002] Escalators are typical public transportation equipment, consisting of a chain conveyor and two belt conveyors with a circulating movement path. They are fixed, electrically driven devices that transport passengers upwards or downwards between different floors of a building. Because they are much more efficient at transporting passengers per unit time than elevators, escalators are increasingly used in shopping malls, airports, high-speed rail stations, subways, hotels, and other places.

[0003] For escalators, timely braking is crucial in emergencies. Generally, existing escalator braking systems work by de-energizing the brake electromagnet on the motor, causing a spring to rebound and press two brake arms against the brake wheel inside the motor. The friction between the brake wheel and the brake shoes on the brake arms dissipates kinetic energy, thus braking the escalator. The braking force depends on the force of the brake arm spring's rebound. Currently, braking force is typically adjusted manually at the factory according to national standards for braking distance. If the manually adjusted braking force is too high, the escalator motor may suddenly lock up during emergency braking. Excessive braking acceleration can easily cause passengers to fall and get injured, and in more serious cases, it can lead to crush accidents.

[0004] Therefore, for existing escalator braking systems, the current common method for anti-lock braking is a point braking method similar to automotive ABS, which involves continuously opening and closing the brake to prevent over-braking. However, this method has the following drawbacks: First, for escalators that commonly use the S1 continuous duty system, the continuous opening and closing of the brake electromagnet is unsuitable. Second, the very short braking time of escalators necessitates a high frequency of brake opening and closing, and electrical components cannot withstand such frequent switching. Third, the escalator brake electromagnet coil requires time to discharge before the brake arm can close. With the high frequency of opening and closing, the brake arm may not have completed its discharge braking process before the next electromagnet is energized, meaning the brake arm never actually presses against the motor brake wheel, failing to achieve the braking purpose. Furthermore, the brake shoe thickness changes over time, and current anti-lock braking methods cannot adjust the brake arm's movement distance accordingly. This leads to a decline in the escalator's braking performance with increasing usage time, undoubtedly increasing safety hazards. Summary of the Invention

[0005] The purpose of this application is to at least solve one of the technical problems existing in the prior art, and to provide an escalator anti-lock braking system and its working method, which can uniformly reduce braking acceleration and automatically adjust the braking force of the brake shoes on the brake wheel.

[0006] According to a first aspect of this application, an escalator braking anti-lock system is provided, comprising: Brake wheel; A braking mechanism includes a brake arm, brake shoes, and a brake electromagnet. The brake shoes are mounted on the brake arm and can come into contact with the brake wheel and brake by mutual friction. When the brake electromagnet is energized, it can generate a magnetic force on the brake arm and drive the brake shoes away from the brake wheel. A closing spring is connected to the brake arm and drives the brake shoe to approach the brake wheel. The spring force of the closing spring is less than the magnetic force generated by the brake electromagnet. The brake coil, when energized, can generate a magnetic force on the brake arm and drive the brake shoe away from the brake wheel; A variable resistance mechanism is electrically connected to the brake coil to adjust the output current to the brake coil. An energy storage capacitor, which is electrically connected to the variable resistor mechanism; The controller includes the brake electromagnet, the brake coil, the variable resistance mechanism, and the energy storage capacitor, all of which are electrically connected to the controller.

[0007] According to the first aspect of the present application, the number of braking mechanisms is two, and the two braking mechanisms are symmetrically arranged on both sides of the brake wheel. According to a first aspect embodiment of this application, the brake coil is further disposed inside the brake wheel and simultaneously applies magnetic force to both brake arms.

[0008] According to a first aspect embodiment of this application, the variable resistance mechanism further includes a sliding rheostat and a servo motor. The sliding rheostat is electrically connected to the brake coil to adjust the output current to the brake coil, and the servo motor is connected to the variable resistance slider of the sliding rheostat to drive the variable resistance slider to move.

[0009] According to a first aspect embodiment of this application, the escalator anti-lock braking system further includes a current transformer for detecting the operating current of the escalator's drive motor, and the current transformer is electrically connected to the controller.

[0010] According to a second aspect of this application, a working method based on the above-mentioned escalator anti-lock braking system is provided, including 6. a debugging stage, an operation stage, and a braking stage; The debugging phase includes: Obtain the operating current A1 of the drive motor of the escalator under no-load conditions and the operating current A2 under rated operating conditions. The operating current of the drive motor is A, and the value range of A is A1≤A≤A2. The operating current a1 required for braking under no-load conditions and the operating current a2 required for braking under rated operating conditions are obtained. The input current of the brake coil is a, and the value range of a is a1≤a≤a2. The operating current A of the drive motor and the input current a of the brake coil have a linear relationship, and the linear relationship between the two is obtained; The operational phase includes: When the controller is connected to an external power source, the brake electromagnet is energized and drives the brake shoe away from the brake wheel, and the energy storage capacitor is charged to store electrical energy. The controller obtains the actual operating current A0 (A0∈A) of the drive motor, and adjusts the variable resistance mechanism based on the relationship between the operating current A of the drive motor and the input current a of the brake coil, thereby adjusting the resistance value corresponding to the input current a0 (a0∈a) output to the brake coil. The braking phase includes: In the event of a sudden situation, the controller disconnects from the external power supply, the brake electromagnet releases the brake arm, and the brake shoe moves toward the brake wheel under the drive of the closing spring. The energy storage capacitor supplies power to the brake coil through the variable resistance mechanism. At this time, the instantaneous input current of the brake coil is a0. The brake coil drives the brake shoe away from the brake wheel. At this time, the force of the brake shoe on the brake wheel is equal to the elastic force of the closing spring minus the magnetic force of the brake coil. When the brake wheel is brought to a stop, the escalator braking is complete.

[0011] According to a second aspect embodiment of this application, the controller further includes an instantaneous relay and a time-delayed relay. The instantaneous relay is electrically connected to an external power source, and the time-delayed relay is electrically connected to the energy storage capacitor. The controller can adjust the delay time t of the time-delayed relay. In the event of an emergency, the instantaneous relay immediately disconnects from the external power source, and the time-delayed relay starts timing and disconnects the power supply from the energy storage capacitor to the brake coil after the delay time t is reached.

[0012] According to a second aspect of the embodiment of this application, the escalator anti-lock braking system further includes a step speed sensor, which is electrically connected to the controller and used to detect the running speed of the escalator. In case of an emergency, the controller cuts off the external power supply and starts timing until the step speed sensor detects that the escalator has completed braking, and records the braking time of the escalator as T. If the delay time t is the same as the braking time T, no adjustment is needed. If the delay time t is greater than the braking time T, the delay time t is adjusted to be the same as the braking time T. If the delay time t is less than the braking time T, it is assumed that the brake shoe is worn, and the variable resistance mechanism is adjusted to change the input current a to the brake coil.

[0013] According to a second aspect embodiment of this application, the escalator anti-lock braking system further includes a distance sensor, which is electrically connected to the controller and used to detect the distance between the brake shoe and the brake wheel. During operation, after the controller is powered on by an external power source, it obtains the distance L1 between the brake shoe and the distance sensor when the brake shoe is open, and the distance L2 between the brake shoe and the distance sensor when the brake shoe is closed, and records the movement distance ΔL = |L1-L2| of the brake shoe. By comparing ΔL at the current start-up with that at the last start-up, it checks whether the brake shoe is worn. If there is wear, the variable resistance mechanism is adjusted to change the input current a to the brake coil.

[0014] According to the second aspect of the embodiment of this application, further, when adjusting the input current a of the brake coil, the input current a is reduced by 1% to obtain a', and the input current a' of the brake coil is used to obtain the new moving distance ΔL' of the brake shoe. Let the measurement value C = (|ΔL - ΔL'|) / ΔL; if C ≤ 1%, the adjustment is considered complete; if C > 1%, the input current a' is reduced by another 1% and the above adjustment is continued.

[0015] The beneficial effects of the embodiments of this application include at least the following: the application generates a repulsive magnetic force on the brake arm through the brake coil, thereby reducing the instantaneous braking force of the brake shoe on the brake wheel during braking, making the braking more uniform and smooth; the magnetic force of the brake coil can be controlled by the controller, thereby automatically adjusting according to the actual situation. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly explained below. Obviously, the described drawings are only a part of the embodiments of this application, and not all of them. Those skilled in the art can obtain other design schemes and drawings based on these drawings without creative effort.

[0017] Figure 1 This is a top view of the escalator anti-lock braking system according to the first aspect of this application; Figure 2 This is a schematic diagram of the electrical connections of the escalator anti-lock braking system according to the first aspect of this application; Figure 3 This is a flowchart of the commissioning phase of the working method of the escalator anti-lock braking system according to the second aspect embodiment of this application; Figure 4 This is a flowchart of the operation phase of the working method of the escalator anti-lock braking system according to the second aspect embodiment of this application; Figure 5 This is a flowchart of the braking phase in the working method of the escalator anti-lock braking system according to the second aspect of this application.

[0018] Reference numerals: 100-Brake wheel, 200-Brake mechanism, 210-Brake arm, 220-Brake shoe, 230-Extension plate, 300-Closing spring, 400-Distance sensor, 500-Brake coil, 610-Sliding rheostat, 620-Servo motor, 700-Energy storage capacitor, 800-Step speed sensor, 900-Controller, 910-Instantaneous relay, 911-Instantaneous contact switch, 920-Time delay relay, 921-Time delay contact switch, 1000-Current transformer, 1100-External power supply. Detailed Implementation

[0019] This section will describe in detail the specific embodiments of this application. Preferred embodiments of this application are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of this application, but they should not be construed as limiting the scope of protection of this application.

[0020] In the description of this application, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0021] In the description of this application, "several" means one or more, "more than" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0022] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0023] Reference Figures 1 to 2 The escalator anti-lock braking system in the first aspect of this application includes a brake wheel 100, a brake mechanism 200, a closing spring 300, a distance sensor 400, a brake coil 500, a variable resistance mechanism, an energy storage capacitor 700, a step speed sensor 800, and a controller 900. The brake wheel 100 is connected to the drive wheel of the escalator. When the brake wheel 100 is stopped, it can also brake the drive wheel of the escalator, thereby stopping the escalator from continuing to run. The brake mechanism 200 is the main component that performs the braking function, and it includes a brake arm 210, brake shoes 220, and a brake electromagnet (not shown in the figure). The brake shoes 220 are installed on the brake arm 210 and can move with the brake arm 210. The brake shoes 220 can contact the brake wheel 100 and dissipate kinetic energy through mutual friction, thereby braking the brake wheel. When the brake electromagnet is energized, it can generate a magnetic force on the brake arm 210, thereby driving the brake arm 210 to move, which in turn drives the brake shoe 220 away from the brake wheel 100 to release the braking state.

[0024] The closing spring 300 primarily provides the braking force required to bring the brake wheel 100 to a stop. It connects to the brake arm 210 and drives the brake shoe 220 closer to the brake wheel, but its spring force is less than the magnetic force generated by the brake electromagnet. During normal operation, the brake electromagnet is energized, causing the brake shoe 220 to open, at which point the brake shoe 220 disengages from the brake wheel 100. During braking, the brake electromagnet is de-energized, and the closing spring 300 drives the brake shoe 220 to close, at which point the brake shoe 220 presses firmly against the brake wheel 100, completing the braking operation.

[0025] The distance sensor 400 is used to detect the distance between the brake shoe 220 and the brake wheel 100. By recording the distance the brake shoe 220 moves during each braking, it is possible to analyze whether the brake shoe 220 is worn, thus providing data support for later maintenance.

[0026] When the brake coil 500 is energized, it can generate a magnetic force on the brake arm 210 and drive the brake shoe 220 away from the brake wheel 100 to counteract part of the braking force at the moment of braking, thereby playing an anti-lock function and making the braking smoother.

[0027] The variable resistance mechanism is electrically connected to the brake coil 500 to adjust the output current of the brake coil 500. Its working logic is that when the escalator load is large, the current input to the brake coil 500 is reduced, which reduces the cancellation of the braking force of the closing spring 300, thereby enabling a greater braking force to brake the brake wheel 100; when the escalator load is small, the current input to the brake coil 500 is increased, which increases the cancellation of the braking force of the closing spring 300, thereby enabling a smaller braking force to brake the brake wheel 100, preventing the danger of locking up due to excessive instantaneous braking force.

[0028] The energy storage capacitor 700 is electrically connected to the variable resistor mechanism. When the power is off, the electrical energy stored in it can be input to the brake coil 500 through the variable resistor mechanism.

[0029] A step speed sensor 800 is installed on the escalator to detect the actual operating speed of the escalator, thereby achieving closed-loop control of the escalator. Specifically, each step sends a pulse signal to the controller 900 when it passes the step speed sensor 800. The controller 900 then calculates the running speed of the escalator steps in real time based on the preset step width parameters.

[0030] The brake electromagnet, distance sensor 400, brake coil 500, variable resistance mechanism, energy storage capacitor 700 and step speed sensor 800 are all electrically connected to the controller 900, which is used to monitor and control the escalator's anti-lock braking system.

[0031] Furthermore, there are two braking mechanisms 200, which are symmetrically arranged on both sides of the brake wheel 100, making braking smoother. The number of closing springs 300 can be set to two and connected one-to-one with each braking mechanism 200, or one closing spring 300 can have both ends connected to two brake arms 210, pulling them simultaneously towards the brake wheel 100 to apply braking force.

[0032] Furthermore, the brake wheel 100 is ring-shaped, and the brake coil 500 is located inside the brake wheel 100, simultaneously applying magnetic force to the two brake arms 210, thereby making the structure more compact.

[0033] Furthermore, the variable resistance mechanism includes a sliding rheostat 610 and a servo motor 620. The sliding rheostat 610 is electrically connected to the brake coil 500 to adjust the output current to the brake coil 500. The swing arm of the servo motor 620 is connected to the variable resistance slider of the sliding rheostat 610, so that when the swing arm of the servo motor 620 rotates, it can drive the variable resistance slider to move, thereby adjusting the resistance of the sliding rheostat 610.

[0034] Furthermore, the escalator braking anti-lock braking system also includes a current transformer 1000, which is used to detect the operating current of the escalator's drive motor and is electrically connected to the controller 900, thereby enabling the drive motor's operating current data to be fed back to the controller 900.

[0035] The working method of the escalator anti-lock braking system in the second aspect embodiment of this application, based on the above-mentioned escalator anti-lock braking system, includes a commissioning stage, an operation stage, and a braking stage.

[0036] Reference Figure 3 The debugging phase includes the following steps: S110. By using a current transformer 1000 or other detection instrument capable of measuring current values, obtain the operating current A1 of the drive motor of the escalator under no-load conditions and the operating current A2 under rated operating conditions. Let the operating current of the drive motor be A, and it can be seen that the range of A is A1≤A≤A2. S120. Obtain the operating current a1 required for braking under no-load conditions and the operating current a2 required for braking under rated operating conditions of the brake coil 500. The input current of the brake coil is a, and it can be seen that the range of a is a1≤a≤a2. S130. It is known that there is a linear relationship between the operating current A of the drive motor and the input current a of the brake coil 500. By obtaining the linear relationship between the two, the specific value of the input current a of the brake coil 500 to achieve smooth braking under different load conditions can be obtained.

[0037] Reference Figure 4 The operation phase includes the following steps: S210. When the controller 900 connects to the external power supply 1100, the brake electromagnet is energized and drives the brake shoe 220 away from the brake wheel 100, thus engaging the braking state. The energy storage capacitor 700 is charged to store electrical energy. S220. The controller 900 obtains the actual operating current A0 (A0∈A) of the drive motor, and adjusts the variable resistance mechanism based on the relationship between the operating current A of the drive motor and the input current a of the brake coil 500, thereby adjusting the resistance value corresponding to the input current a0 (a0∈a) output to the brake coil 500.

[0038] Reference Figure 5 The braking phase includes the following steps: S310. In the event of a sudden situation, the controller 900 disconnects from the external power supply 1100, causing the brake electromagnet to release the brake arm 210, and the brake shoe 220 moves toward the brake wheel 100 and presses against the brake under the drive of the closing spring 300. S320. The energy storage capacitor 700 supplies power to the brake coil 500 through the variable resistor mechanism. At this time, the instantaneous input current of the brake coil 500 is a0. The brake coil 500 drives the brake shoe 220 away from the brake wheel 100. At this time, the force of the brake shoe 220 on the brake wheel 100 is equal to the elastic force of the closing spring 300 minus the magnetic force of the brake coil 500. S330. The final brake wheel 100 is brought to a stop, and the escalator braking is completed.

[0039] Specifically, the controller 900 is equipped with an instantaneous relay 910 and a time-delay relay 920. The instantaneous relay 910 is electrically connected to the external power supply 1100, and the time-delay relay 920 is electrically connected to the energy storage capacitor 700. The controller 900 can adjust the delay time t of the time-delay relay 920. During the braking phase, when a sudden braking situation occurs, the instantaneous relay 910 immediately disconnects from the external power supply 1100, causing the brake electromagnet to lose power; at the same time, the time-delay relay 920 starts timing and cuts off the power supply from the energy storage capacitor 700 to the brake coil 500 after the delay time t is reached, thereby achieving the effect of automatic power-off.

[0040] Furthermore, the controller 900 can adaptively adjust the delay time t. In case of an emergency, the controller 900 starts timing simultaneously after cutting off the external power supply, until the step speed sensor detects that the escalator speed is 0, indicating that the escalator has completed braking. The braking time T of the escalator is recorded, and the controller 900 compares whether the braking time T is consistent with the delay time t: if they are consistent, it means that the escalator was just stopped after the delay time t ends, and the delay time t does not need to be adjusted; if the delay time t is greater than the braking time T, it means that the escalator needs to stop earlier than preset, and the delay time t can be adjusted to be consistent with the braking time T to save energy; if the delay time t is less than the braking time T, it means that the escalator has not completed braking by the end of the delay time t, the braking force is too small, and it is believed that the brake shoe 220 may be worn, requiring maintenance or adjustment of the variable resistance mechanism to change the input current a to the brake coil 500.

[0041] To detect the wear of the brake shoe 220, during operation, after the controller 900 is connected to the external power supply 1100, the distance L1 between the brake shoe 220 and the distance sensor 400 when the brake shoe 220 is open, and the distance L2 between the brake shoe 220 and the distance sensor 400 when the brake shoe 220 is closed, are obtained through the distance sensor 400. The movement distance ΔL of the brake shoe 220 is recorded as |L1-L2|. The movement distance ΔL of the brake shoe 220 is detected each time the system is started. By comparing whether the movement distance ΔL changes each time, it is determined whether the brake shoe is worn. If wear is found, the variable resistance mechanism is adjusted to change the input current a to the brake coil 500.

[0042] Regarding the adjustment method of input current a, the input current a is reduced by 1% to obtain a', and the input current a' to the brake coil 500 is used to obtain the new moving distance △L' of the brake shoe 220. Let the measurement value be C = (|△L - △L'|) / △L; if C ≤ 1%, the adjustment is considered complete; if C > 1%, it means that △L' is large and the wear of the brake shoe 220 is more serious. The input current a' is reduced by another 1% and the above adjustment is continued until the condition of C ≤ 1% is met.

[0043] The above is a detailed description of the preferred embodiments of this application. However, this application is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of this application. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. A method for operating an escalator braking anti-lock braking system, characterized in that: The escalator braking anti-lock system includes: Brake wheel; A braking mechanism includes a brake arm, brake shoes, and a brake electromagnet. The brake shoes are mounted on the brake arm and can come into contact with the brake wheel and brake by mutual friction. When the brake electromagnet is energized, it can generate a magnetic force on the brake arm and drive the brake shoes away from the brake wheel. A closing spring is connected to the brake arm and drives the brake shoe to approach the brake wheel. The spring force of the closing spring is less than the magnetic force generated by the brake electromagnet. The brake coil, when energized, can generate a magnetic force on the brake arm and drive the brake shoe away from the brake wheel; A variable resistance mechanism is electrically connected to the brake coil to adjust the output current to the brake coil. An energy storage capacitor, which is electrically connected to the variable resistor mechanism; The controller, the brake electromagnet, the brake coil, the variable resistance mechanism and the energy storage capacitor are all electrically connected to the controller; The working method of the escalator anti-lock braking system includes a commissioning phase, an operation phase, and a braking phase. The debugging phase includes: Obtain the operating current A1 of the drive motor of the escalator under no-load conditions and the operating current A2 under rated operating conditions. The operating current of the drive motor is A, and the value range of A is A1≤A≤A2. The operating current a1 required for braking under no-load conditions and the operating current a2 required for braking under rated operating conditions are obtained. The input current of the brake coil is a, and the value range of a is a1≤a≤a2. The operating current A of the drive motor and the input current a of the brake coil have a linear relationship, and the linear relationship between the two is obtained; The operational phase includes: When the controller is connected to an external power source, the brake electromagnet is energized and drives the brake shoe away from the brake wheel, and the energy storage capacitor is charged to store electrical energy. The controller obtains the actual operating current A0 (A0∈A) of the drive motor, and adjusts the variable resistance mechanism based on the relationship between the operating current A of the drive motor and the input current a of the brake coil, thereby adjusting the resistance value corresponding to the input current a0 (a0∈a) output to the brake coil. The braking phase includes: In the event of a sudden situation, the controller disconnects from the external power supply, the brake electromagnet releases the brake arm, and the brake shoe moves toward the brake wheel under the drive of the closing spring. The energy storage capacitor supplies power to the brake coil through the variable resistance mechanism. At this time, the instantaneous input current of the brake coil is a0. The brake coil drives the brake shoe away from the brake wheel. At this time, the force of the brake shoe on the brake wheel is equal to the elastic force of the closing spring minus the magnetic force of the brake coil. When the brake wheel is brought to a stop, the escalator braking is complete.

2. The method of operating an escalator brake antilock system according to claim 1, wherein: The number of braking mechanisms is two, and the two braking mechanisms are symmetrically arranged on both sides of the brake wheel.

3. The method of operating an escalator brake antilock system according to claim 2, wherein: The brake coil is located inside the brake wheel and simultaneously applies magnetic force to both brake arms.

4. The method of operating an escalator brake antilock system according to claim 1, wherein: The variable resistance mechanism includes a sliding rheostat and a servo motor. The sliding rheostat is electrically connected to the brake coil to adjust the output current to the brake coil, and the servo motor is connected to the variable resistance slider of the sliding rheostat to drive the variable resistance slider to move.

5. The method of operating an escalator brake antilock system according to claim 1, wherein: The escalator anti-lock braking system also includes a current transformer, which is used to detect the operating current of the escalator's drive motor and is electrically connected to the controller.

6. The method of operating an escalator brake antilock system according to claim 1, wherein: The controller is equipped with an instantaneous relay and a time-delay relay. The instantaneous relay is electrically connected to an external power source, and the time-delay relay is electrically connected to the energy storage capacitor. The controller can adjust the delay time t of the time-delay relay. In case of an emergency, the instantaneous relay immediately disconnects from the external power source, and the time-delay relay starts timing and cuts off the power supply from the energy storage capacitor to the brake coil after the delay time t is reached.

7. A method of operating an escalator brake antilock system according to claim 6, characterized in that: The escalator braking anti-lock system also includes a step speed sensor, which is electrically connected to the controller and used to detect the running speed of the escalator. In case of an emergency, the controller cuts off the external power supply and starts timing until the step speed sensor detects that the escalator has completed braking, and records the braking time of the escalator as T. If the delay time t is the same as the braking time T, no adjustment is needed; if the delay time t is greater than the braking time T, adjust the delay time t to be the same as the braking time T. If the delay time t is less than the braking time T, it is assumed that the brake shoe is worn, and the variable resistance mechanism is adjusted to change the input current a to the brake coil.

8. The method of operating an escalator brake antilock system according to claim 1, wherein: The escalator anti-lock braking system also includes a distance sensor, which is electrically connected to the controller and used to detect the distance between the brake shoe and the brake wheel. During operation, after the controller is powered on by an external power source, it uses the distance sensor to obtain the distance L1 between the brake shoe and the distance sensor when the brake shoe is open, and the distance L2 between the brake shoe and the distance sensor when the brake shoe is closed. The movement distance of the brake shoe is recorded as ΔL = |L1 - L2|. By comparing ΔL at the current start-up with that at the last start-up, the wear of the brake shoe is checked. If wear is found, the variable resistance mechanism is adjusted to change the input current a to the brake coil.

9. The method of operating an escalator brake antilock system according to claim 8, wherein: When adjusting the input current a of the brake coil, reduce the input current a by 1% to obtain a', and input the brake coil current a' to obtain the new moving distance ΔL' of the brake shoe. Let the measurement value C = (|ΔL - ΔL'|) / ΔL; if C ≤ 1%, the adjustment is considered complete; if C > 1%, reduce the input current a' by another 1% and continue the above adjustment.

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