Abstract:
The present invention relates to a safe operation-stop method for an escalator for safely operating and stopping an escalator that senses an abnormal speed of the escalator so as to prevent passengers from falling. A safe operation-stop method for an escalator is provided, the method including sensing an abnormal speed of the escalator and stopping the escalator before it is reversely rotated, and being capable of reliable braking when an abnormal speed of the escalator occurs, thereby preventing passengers from falling by adjusting the inertial stopping distance when braking.

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to a method for safely stopping the operation of an escalator and, more particularly, to a method for safely stopping the operation of an escalator, wherein an abnormal speed of an escalator is detected and the operation of the escalator is safely stopped in order to prevent a fall of a passenger. 
     Discussion of the Related Art 
     As noted, there have been suggested conventional technologies for stopping an escalator when abnormality is generated in the escalator. A representative example includes Korean Patent No. 10-0995059 entitled “Safety Brake Control Apparatus for Emergency Stop of Escalator” (hereinafter referred to as a “cited invention”). 
     As shown in  FIG. 1 , cited invention may include the steps of checking whether an escalator ascends or descends, detecting whether counter rotation is generated using a counter rotation detection sensor if the escalator ascends and detecting a descending speed using an overspeed detection sensor if the escalator descends; blocking the supply of power to a driving motor and driving a main brake by sending a block signal to the safety circuit of a main control panel if a descending speed of the escalator detected by the overspeed detection sensor exceeds 120% of a rating speed; and driving an emergency stop safety brake by driving a relay panel if counter rotation is detected by the counter rotation detection sensor or a descending speed of the escalator detected by the overspeed detection sensor exceeds 140% of the rating speed. 
     Such a cited invention can prevent a safety accident attributable to a malfunction of the escalator by stopping the escalator by the emergency stop safety brake having a braking power according to the friction contact of a disk brake when counter rotation is detected by the counter rotation detection sensor or the overspeed operation of the escalator is detected by the overspeed detection sensor. However, such a stop method corresponds to a friction stop and thus has a problem in that the braking power is reduced because the disk brake of the emergency stop safety brake is worn out as it is used. The emergency stop safety brake has a reduced braking power as described above or is useless if it left as it has a problem in operation because the emergency stop safety brake is not always used, but is used when abnormality is generated. Furthermore, in the cited invention, braking is performed after counter rotation is detected by the counter rotation detection sensor. The cited invention has a problem in that a fall of a passenger is increased because braking is performed when the driving chain is broken and stopped while the escalator ascends and is accelerated in the descending direction by counter rotation. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a method for safely stopping the operation of an escalator, which stops an escalator prior to counter rotation by detecting an abnormal speed of the escalator, performs reliable braking when an abnormal speed of the escalator is generated, and prevents a fall of a passenger by adjusting a stop distance according to inertia when such braking is performed. 
     According to an aspect of the present invention, there is provided a method for safely stopping the operation of an escalator including a driving motor equipped with a main brake, a main control panel for controlling the driving motor, an emergency brake apparatus for performing emergency braking on the escalator, and a brake unit for controlling the emergency brake apparatus, wherein the main control panel and the brake unit communicate with each other, the driving motor and the driving sprocket of a driving shaft are connected by a driving chain, and a step sprocket rotated when the driving shaft is rotated by the motive power of the driving motor drives a step connected on an endless track through step chains, the method comprising: 
     a characteristic storage step for storing, by the brake unit, characteristics of the escalator while the escalator is configured and started up; a braking step for dividing, by the brake unit, a moving speed of the escalator into multiple stages, determining abnormality, and performing braking based on the determination; and a test braking step for performing, by the brake unit, test braking in order to test the emergency brake apparatus when the operation of the escalator is normally terminated. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view showing the configuration of cited invention. 
         FIG. 2  is a flowchart illustrating an overall configuration of a method for safely stopping the operation of an escalator according to the present invention. 
         FIG. 3  shows a detailed configuration of an emergency brake apparatus applied to the method for safely stopping the operation of an escalator according to the present invention. 
         FIG. 4  is a detailed circuit diagram of the emergency brake apparatus applied to the method for safely stopping the operation of an escalator according to the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     A method for safely stopping the operation of an escalator including a driving motor, a main control panel for controlling the driving motor, an emergency brake apparatus for performing emergency braking on the escalator, and a brake unit for controlling the emergency brake apparatus, wherein the main control panel and the brake unit communicate with each other, the driving motor and the driving sprocket of a driving shaft are connected by a driving chain, and a step sprocket rotated when the driving shaft is rotated by the motive power of the driving motor drives a step connected on an endless track through step chains, the method comprising: 
     a characteristic storage step for storing, by the brake unit, characteristics of the escalator while the escalator is configured and started up; a braking step for dividing, by the brake unit, a moving speed of the escalator into multiple stages, determining abnormality, and performing braking based on the determination; and a test braking step for performing, by the brake unit, test braking in order to test the emergency brake apparatus when the operation of the escalator is normally terminated. 
     Embodiments of the present invention are described in detail below with reference to the accompanying drawings so that those skilled in the art to which the present invention pertains readily implement the present invention. 
     An overall configuration of a method for safely stopping the operation of an escalator according to the present invention is shown in  FIG. 3 . 
     Referring to  FIG. 3 , an escalator according to the present invention includes a driving motor  200  equipped with a main brake  202 , a main control panel  100  controlling the driving motor  200 , an emergency brake apparatus  500  performing emergency braking on the escalator, and a brake unit  400  controlling the emergency brake apparatus  500 . 
     The main control panel  100  and the brake unit  400  communicate with each other. The driving motor  200  and the driving sprocket  301  of a driving shaft  300  are connected by a driving chain  201 . A step sprocket  302  rotated when the driving shaft  300  is rotated by the motive power of the driving motor  200  drives a step connected on an endless track through step chains. 
     A method for safely stopping the operation of the escalator may includes: 
     a characteristic storage step for storing, by the brake unit  400 , the characteristics of the escalator while the escalator is configured and started up, 
     a braking step for dividing, by the brake unit  400 , a moving speed of the escalator into multiple stages, determining abnormality, and performing braking based on the determination, and 
     a test braking step for performing, by the brake unit  400 , test braking in order to test the emergency brake apparatus  500  when the operation of the escalator is normally terminated. 
     Each of the elements is described in more detail below. The main control panel  100  and the brake unit  400  may be configured using a single control apparatus. If the main control panel  100  and the brake unit  400  are separately configured, they communicate with each other. The main control panel  100  starts up and stops the escalator, and outputs a normal moving signal to the brake unit  400  during a normal operation. When an abnormal signal is received from the brake unit  400 , the main control panel  100  blocks output of the normal moving signal and stops the escalator by driving the main brake  202 . The brake unit  400  determines abnormality by detecting an operation speed of the escalator and performs control for emergency braking on the escalator. 
     Furthermore, the characteristic storage step may include a test braking number setting step for counting the number of normal operation terminations when the operation of the escalator is terminated, performing emergency braking by the emergency brake apparatus  500  other than common braking by the main brake  202  at a point of time at which the operation of the escalator is terminated when a specific number of operations is reached, and setting a test braking number so that the operation test of the emergency brake apparatus  500  can be executed, a step for setting the escalator in a setting mode, starting up the escalator for a test, and storing a start-up characteristic from the stop state of the escalator to the normal moving state of the escalator and a normal moving characteristic in the normal moving state, and a step for storing a braking characteristic upon braking and a before-stop deceleration characteristic right before the escalator is stopped in the normal moving state of the escalator that moves in the setting mode. 
     An acceleration time in normal operation may be set based on the start-up characteristic. A normal speed may be set based on the normal moving characteristic. A first setting speed and a second setting speed may be set depending on a degree of overspeed based on the normal speed. A third setting speed and a fourth setting speed may be set depending on a degree of deceleration based on the normal speed. A deceleration time may be set based on the braking characteristic. 
     By repeatedly performing such a characteristic storage step, a start-up characteristic, a normal moving characteristic, a braking characteristic, and a deceleration characteristic prior to a stop according to an installation environment or the deflection and state of a machine itself may be set as average values for each escalator. The first setting speed to the fourth setting speed, that is, criteria for an abnormal determination, can be set based on such characteristic values. Accordingly, the abnormality of an escalator can be determined more accurately and reliably. 
     Furthermore, the braking step may include: 
     a primary overspeed regulation step for determining the escalator to move at overspeed if a moving speed of the escalator detected by the brake unit  400  is a set first setting speed or more in the state in which the escalator has started up in a normal mode and the main control panel  100  outputs a moving signal indicating that the escalator normally moves, sending, by the brake unit  400 , an abnormal signal to the main control panel  100 , outputting a warning message, and stopping, by the main control panel  100 , the escalator by driving the main brake  202  of the driving motor  200 , 
     a secondary overspeed braking step for determining that the escalator is suddenly accelerated because the driving chain  201  is broken while the escalator descends if the moving speed of the escalator is a set second setting speed or more, driving, by the brake unit  400 , the emergency brake apparatus  500 , and outputting a warning message, 
     a primary deceleration regulation step for determining the escalator to be an overload state if the moving speed of the escalator is a set third setting speed or less and outputting, by the brake unit  400 , a warning message indicative of the overload state of the escalator through an LED, a speaker, a display and/or a text message in order to prevent no more boarding, 
     a secondary deceleration the braking step for determining that the escalator has been suddenly decelerated because an object is got between the steps of the escalator if the moving speed of the escalator is a set fourth setting speed or less and sending, by the brake unit  400 , an abnormal signal to the main control panel  100  so that the escalator is immediately stopped, and 
     a before-counter rotation emergency braking step for determining that the driving chain  201  has been broken while the escalator ascends when the brake unit  400  receives a moving signal from the main control panel  100  and a deceleration characteristic prior to a stop for the escalator is detected, stopping the escalator by driving the emergency brake apparatus  500  before the escalator descends, and outputting a warning message. 
     More specifically, as illustrated in  FIGS. 3 and 4 , in the secondary overspeed braking step, the emergency brake apparatus  500  configured using a permanent magnet motor is connected to the driving shaft  300  of the escalator through an electronic clutch  505 . The emergency brake apparatus  500  may be separated from the driving shaft  300  at normal times. When a moving speed of the escalator is suddenly accelerated at a set second setting speed or more, the brake unit  400  drives the electronic clutch  505  so that the driving shaft  300  and the permanent magnet motor are connected. Accordingly, the escalator can be decelerated and braked by power generation braking of the permanent magnet motor. As shown in  FIG. 4 , Insulated Gate Bipolar Transistors (IGBTs), that is, a plurality of switching means  401 , is connected to a plurality of windings, that is, the stators  502  of the permanent magnet motor. Furthermore, a stop distance according to inertia upon braking performed by the brake unit  400  for controlling a rotation load applied to the rotor  501  of the permanent magnet motor by supplying an operation pulse to the switching means  401  can be adjusted. Accordingly, a fall of a passenger occurring when the escalator is decelerated and braked during overspeed can be prevented. 
     As described above, in the braking step, an abnormal state which may occur in the escalator is determined to be multiple stages based on a moving speed of the escalator, and braking suitable for each situation is performed. Accordingly, the operation of the escalator can be safely stopped because a braking method, a braking distance, and a braking speed can be controlled in order to prevent the expansion of a safety accident to a human life accident when passengers who stand on the escalator fall down while the escalator moves. 
     Furthermore, in general, the escalator includes the driving motor  200  equipped with the main brake  202 . The escalator is started up by driving the driving motor  200  under the control of the main control panel  100 . The driving motor  200  is stopped by driving the main brake  202 , thereby stopping the escalator. When the driving chain  201  is broken and common abnormality other than the state in which braking is not performed due to the stop of the driving motor  200  is generated, braking is performed by the main brake  202 . 
     Accordingly, the emergency brake apparatus  500  that is less frequently used may corrode, an alien substance may be cut in the emergency brake apparatus  500 , or an abnormal state, such as a modification or the cutting of a wire may occur in the emergency brake apparatus  500 . It is difficult to previously detect factors that generate a problem in the normal operation of the emergency brake apparatus  500 . Accordingly, there is a problem in that a safety accident is expanded due to the abnormal operation of the emergency brake apparatus  500  when abnormality is generated in the escalator. 
     An embodiment of the present invention includes a test braking step in order to improve reliability of the safe stop of the operation of the escalator by solving such a problem. The test braking step may include: 
     a test notification step for counting, by the brake unit  400 , the normal termination of the escalator and providing notification of a test for the emergency brake apparatus  500  upon operation stop when the counted normal termination number reaches a set test braking number, 
     a test step for performing, by the brake unit  400 , test braking by driving the emergency brake apparatus  500  after the test notification step, 
     a determination step for detecting, by the brake unit  400 , output electricity output by the emergency brake apparatus  500  in the test step and determines whether the emergency brake apparatus  500  is abnormal, 
     an abnormality notification step for providing notification that the emergency brake apparatus  500  is abnormal if the emergency brake apparatus  500  is determined to be abnormal in the determination step, and 
     a re-start-up notification step for providing notification of the abnormality of the emergency brake apparatus  500  if the escalator is started up again in the state in which the abnormality of the emergency brake apparatus  500  has not been solved. 
     Accordingly, in accordance with the present invention, the emergency brake apparatus  500  is periodically checked and tested at normal times. When abnormality is detected, the abnormality of the emergency brake apparatus  500  can be solved in advance before an accident occurs. Accordingly, the safety of the escalator can be further improved because the operation of the emergency brake apparatus  500  is reliably performed when the escalator is abnormal. 
     As described above, according to the present invention, abnormality in the escalator is determined when overspeed or deceleration is detected while the escalator operates depending on characteristics of the escalator, and braking suitable for each situation is performed. Furthermore, while the escalator ascends based on a before-stop deceleration characteristic, when the driving chain is broken and stopped, before the escalator descends, abnormality in the escalator is detected. Accordingly, the emergency brake apparatus is driven when the escalator is stopped before it is reversed. Accordingly, a fall of a passenger can be prevented and effective braking can be performed. 
     In the test braking step, the emergency brake apparatus is periodically checked and tested at normal times. Accordingly, when abnormality is detected, the abnormality of the emergency brake apparatus can be solved in advance before an accident occurs. Accordingly, there is an advantage in that the safety of the escalator can be further improved because the operation of the emergency brake apparatus is reliably performed when abnormality is generated in the escalator. 
     Furthermore, in the present invention, if the emergency brake apparatus is configured using a permanent magnet motor, the permanent magnet motor is connected to the driving shaft of the escalator through the electronic clutch. At normal times, the emergency brake apparatus is separated from the driving shaft of the escalator. When a moving speed of the escalator is a set second setting speed or more, the driving shaft and the permanent magnet motor are connected by the operation of the electronic clutch. Accordingly, the escalator is decelerated and braked by power generation braking of the permanent magnet motor. Furthermore, the plurality of switching means is connected to the plurality of windings, that is, the stators of the permanent magnet motor. A stop distance according to inertia upon braking can be adjusted by the brake unit for controlling a rotation load applied to the rotor of the permanent magnet motor by supplying an operation pulse to the switching means. Accordingly, there is an advantage in that a fall of a passenger upon deceleration braking during overspeed can be prevented. 
     As described above, the present invention is not limited to the aforementioned embodiments, but may be changed and implemented in various ways without departing from a gist and concept intended by the present invention.