Brake system and elevator system

Abstract

The embodiment of the invention relates to the technical field of elevators, and provides a band-type brake system and an elevator system.The band-type brake system comprises an alternating-current power source, a rectifier bridge, a band-type brake circuit and a relay control circuit, and the band-type brake circuit is connected with the alternating-current power source through the rectifier bridge; the relay control circuit comprises a zero point detection module, a trigger, a controller, a delayer, an actuator and a relay, wherein the zero point detection module is connected to two output ends of an alternating current power supply in parallel; the zero point detection module and the trigger are connected in parallel to the input end of the controller; the delayer is connected with the output end of the controller; the actuator is connected with the delayer; a coil of the relay is connected with the actuator, a contact point of the relay is connected between the rectifier bridge and the alternating current power supply, and the actuator controls the sum of preset closing time of closing of the contact point of the relay and preset delay time of the delayer to be equal to the period of the alternating current power supply.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of elevator technology, and in particular to a brake system and an elevator system. Background Art

[0002] The elevator brake system is an important safety component of the elevator. It prevents the elevator from moving when the elevator car is stationary and the motor is in a power-off state. Its control method is generally to release the brake when the brake coil is energized and tighten the brake when the brake coil is de-energized, thereby preventing the elevator car from rising or falling abnormally. The reliability of the opening and closing of the brake device is a necessary condition for the normal operation of the elevator.

[0003] The brake system controls the power on and off of the brake coil through a relay. At the moment the relay is closed, the two contacts of the relay may burn due to the large current flowing through, causing the two contacts to weld or stick together and unable to disconnect normally, thereby causing the brake system to fail. Summary of the invention

[0004] The embodiments of the present application provide a brake system and an elevator system, which are at least beneficial to improving the safety of the brake system.

[0005] According to some embodiments of the present application, on the one hand, the embodiments of the present application provide a brake system, including: an AC power supply, the AC power supply has two output terminals; a rectifier bridge, the rectifier bridge includes two input terminals and two output terminals, and the two input terminals of the rectifier bridge are respectively connected to the two output terminals of the AC power supply; a brake circuit, the brake circuit is connected to the two output terminals of the rectifier bridge; a relay control circuit, the relay control circuit includes: a zero point detection module, the zero point detection module is connected in parallel to the two output terminals of the AC power supply, and the output terminal of the zero point detection module generates a first level signal based on the zero point voltage of the AC power supply; a trigger, which generates a second level signal after being triggered; a controller, the controller includes two input terminals and one output terminal, and one input terminal of the controller is connected to the zero point detection module. The output end of the module is connected, and the other input end of the controller is connected to the trigger. When the first level signal is the same as the second level signal, the output end of the controller outputs a third level signal; a delayer, the delayer is connected to the output end of the controller, the delayer receives the third level signal and outputs a fourth level signal after a preset delay time; an actuator, the actuator is connected to the delayer; a relay, the coil of the relay is connected to the actuator, the contact point of the relay is connected between the rectifier bridge and the AC power supply, the actuator receives the fourth level signal and controls the coil of the relay to be energized so that the contact point of the relay is closed, the actuator receives the fourth level signal and the contact point of the relay is closed after the preset closing time, and the sum of the preset closing time and the preset delay time is equal to the cycle of the AC power supply.

[0006] In some embodiments, the relay includes a first relay and a second relay, the first relay is connected between the positive output terminal of the AC power supply and the positive input terminal of the rectifier bridge, and the second relay is connected between the negative output terminal of the AC power supply and the negative input terminal of the rectifier bridge.

[0007] In some embodiments, the relay includes a first relay and a second relay, and the first relay and the second relay are connected in series between the positive output terminal of the AC power source and the positive input terminal of the rectifier bridge.

[0008] In some embodiments, the delay device includes a first delay device and a second delay device, and the first delay device and the second delay device are connected in parallel to the output end of the controller; the actuator includes a first actuator and a second actuator, the first actuator is connected between the first relay and the first delay device, and the second actuator is connected between the second relay and the second delay device.

[0009] In some embodiments, the controller is an AND gate or a NAND gate.

[0010] In some embodiments, the delay device includes an even number of inverters connected in series.

[0011] In some embodiments, the brake circuit includes a step-down circuit and a brake coil, and the step-down circuit includes: a first switch tube, the first end of the first switch tube is connected to the negative output end of the rectifier bridge; a first inductor, the first end of the first inductor is connected to the second end of the first switch tube; a second switch tube, the first end of the second switch tube is connected to the second end of the first inductor, and the first end of the brake coil is connected to the second end of the second switch tube; a first resistor, the first end of the first resistor is connected to the second end of the brake coil, and the second end of the first resistor is connected to the positive output end of the rectifier bridge; a first diode, the positive end of the first diode is connected to the second end of the first switch tube, and the negative end of the first diode is connected to the positive output end of the rectifier bridge; a first capacitor, the first end of the first capacitor is connected to the second end of the first switch tube, and the second end of the first capacitor is connected to the positive output end of the rectifier bridge.

[0012] In some embodiments, it also includes: a freewheeling circuit, the freewheeling circuit includes a second diode and a transient voltage suppression diode connected in series, the positive terminal of the second diode is connected to the first end of the brake coil, the negative terminal of the second diode is connected to the first end of the transient voltage suppression diode, and the second end of the transient voltage suppression diode is connected to the second end of the brake coil.

[0013] In some embodiments, it also includes: a filter capacitor, a first end of the filter capacitor is connected to the negative output end of the rectifier bridge, and a second end of the filter capacitor is connected to the positive output end of the rectifier bridge.

[0014] According to some embodiments of the present application, the embodiments of the present application further provide an elevator system, including a brake system as described in the embodiments.

[0015] The technical solution provided by the embodiments of the present application has at least the following advantages:

[0016] In the brake system provided in the embodiment of the present application, the brake circuit is connected to the AC power supply through a rectifier bridge, and the rectifier bridge converts the AC power of the AC power supply into DC power to be connected to the brake circuit. When the brake coil in the brake circuit is energized, the brake is released, and when the brake coil is de-energized, the brake is tightened. The relay control circuit is used to control the conduction and disconnection of the relay between the AC power supply and the rectifier bridge, thereby controlling the conduction and disconnection of the brake circuit and the power supply. Among them, the relay control circuit includes a zero point detection module, a trigger, a controller, a delay device and an actuator. The output end of the zero point detection module generates a first level signal based on the zero point voltage of the AC power supply. The trigger generates a second level signal after being triggered. When the first level signal is the same as the second level signal, the output end of the controller outputs a third level signal. In this way, the delay device is triggered at the zero point voltage of the AC power supply. The delay device receives the third level signal and outputs a fourth level signal after a preset delay time. The actuator receives the fourth level signal and controls the coil of the relay to be energized so that the contact point of the relay is closed. Since the contact point of the relay is closed after the actuator receives the fourth level signal after a preset closing time, and the sum of the preset closing time and the delayed delay time is equal to the cycle of the AC power supply, the relay can be closed at the zero point voltage of the AC power supply. At this time, the current flowing through the two contacts of the relay is small, which can reduce the risk of burning of the two contacts of the relay due to the large current flowing through, thereby reducing the probability of the two contacts of the relay sticking, which is beneficial to extending the service life of the relay, avoiding the problem that the brake circuit cannot be controlled, and improving the safety of the brake system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] One or more embodiments are exemplarily illustrated by the pictures in the corresponding drawings. These exemplified descriptions do not constitute a limitation on the embodiments. Unless otherwise specified, the pictures in the drawings do not constitute a scale limitation. In order to more clearly illustrate the embodiments of the present application or the technical solutions in the traditional technology, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figures 1 to 3 A schematic diagram of the circuit structure of a variety of brake systems provided in an embodiment of the present application;

[0019] Figure 4 A timing diagram of various level signals in a relay control circuit provided in an embodiment of the present application;

[0020] Figure 5A schematic diagram of the circuit structure of a specific brake system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0021] As can be seen from the background technology, the safety of the brake system needs to be improved.

[0022] The brake system is very important in the normal operation of the elevator. Usually, the brake system converts AC power into DC power through a rectifier bridge to connect to the brake circuit, and a relay is used between the rectifier bridge and the AC power supply to control the power supply of the brake circuit. If the relay contacts are closed under the high voltage of the AC power supply, the two contacts of the relay may be burned due to the large current flowing through, and then the two contacts are welded or adhered together and cannot be disconnected normally, which will cause the brake system to fail; in addition, the closing of the relay contacts under the high voltage of the AC power supply will also have a certain impact on the power grid.

[0023] In the brake system provided in the embodiment of the present application, the brake circuit is connected to the AC power supply through a rectifier bridge, and the rectifier bridge converts the AC power of the AC power supply into DC power to be connected to the brake circuit. When the brake coil in the brake circuit is energized, the brake is released, and when the brake coil is de-energized, the brake is tightened. The relay control circuit is used to control the conduction and disconnection of the relay between the AC power supply and the rectifier bridge, thereby controlling the conduction and disconnection of the brake circuit and the power supply. Among them, the relay control circuit includes a zero point detection module, a trigger, a controller, a delay device and an actuator. The output end of the zero point detection module generates a first level signal based on the zero point voltage of the AC power supply. The trigger generates a second level signal after being triggered. When the first level signal is the same as the second level signal, the output end of the controller outputs a third level signal. In this way, the delay device is triggered at the zero point voltage of the AC power supply. The delay device receives the third level signal and outputs a fourth level signal after a preset delay time. The actuator receives the fourth level signal and controls the coil of the relay to be energized so that the contact point of the relay is closed. Since the contact point of the relay is closed after the actuator receives the fourth level signal after a preset closing time, and the sum of the preset closing time and the delayed delay time is equal to the cycle of the AC power supply, the relay can be closed at the zero point voltage of the AC power supply. At this time, the current flowing through the two contacts of the relay is small, which can reduce the risk of burning of the two contacts of the relay due to the large current flowing through, thereby reducing the probability of the two contacts of the relay sticking, which is beneficial to extending the service life of the relay, avoiding the problem that the brake circuit cannot be controlled, and improving the safety of the brake system.

[0024] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0025] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0026] In the description of the embodiments of the present application, when a certain component “includes” another component, unless otherwise stated, other components are not excluded and other components may be further included.

[0027] The terms used in the description of the various described embodiments herein are used only to describe specific embodiments and are not intended to be limiting. As used in the description of the various described embodiments and the appended claims, "components" are also intended to include plural forms unless the context clearly indicates otherwise.

[0028] The following will describe the various embodiments of the present application in detail with reference to the accompanying drawings. However, it will be appreciated by those skilled in the art that in the various embodiments of the present application, many technical details are provided in order to enable the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solution claimed in the present application can be implemented.

[0029] Figures 1 to 3 A schematic diagram of the circuit structure of a variety of brake systems provided in an embodiment of the present application.

[0030] refer to Figures 1 to 3On the one hand, an embodiment of the present application provides a brake system, including: an alternating current power supply AC, a rectifier bridge 101, a brake circuit 102 and a relay control circuit, wherein the alternating current power supply AC has two output terminals (a positive output terminal and a negative output terminal); the rectifier bridge 101 includes two input terminals (a positive input terminal and a negative input terminal) and two output terminals (a positive output terminal and a negative output terminal), and the two input terminals of the rectifier bridge 101 are respectively connected to the two output terminals of the alternating current power supply AC; and the brake circuit is connected to the two output terminals of the rectifier bridge 101. The relay control circuit includes: a zero point detection module 111, a trigger 112, a controller 113, a delay device 114, an actuator 115 and a relay. The zero point detection module 111 is connected in parallel to two output ends of the alternating current power supply AC. The output end of the zero point detection module 111 generates a first level signal A based on the zero point voltage of the alternating current power supply AC. The trigger 112 generates a second level signal B after being triggered. The controller 113 includes two input ends and one output end. One input end of the controller 113 is connected to the output end of the zero point detection module 111, and the other input end of the controller 113 is connected to the trigger 112. When the first level signal A is the same as the second level signal B, the controller 113 generates a second level signal B. The output end of the controller 113 outputs a third level signal C; the delay device 114 is connected to the output end of the controller 113, the delay device 114 receives the third level signal C and outputs a fourth level signal D after a preset delay time; the actuator 115 is connected to the delay device 114; the coil of the relay is connected to the actuator 115, the contact point of the relay is connected between the rectifier bridge 101 and the AC power supply AC, the actuator 115 receives the fourth level signal D and controls the coil of the relay to be energized so that the contact point of the relay is closed, and the actuator 115 receives the fourth level signal D and the contact point of the relay is closed after the preset closing time, and the sum of the preset closing time and the preset delay time is equal to the cycle of the AC power supply AC.

[0031] In the brake system provided in the embodiment of the present application, the brake circuit 102 is connected to the AC power source AC through the rectifier bridge 101. The rectifier bridge 101 converts the AC power of the AC power source AC into DC power to be connected to the brake circuit 102. When the brake coil in the brake circuit 102 is energized, the brake is released, and when the brake coil is de-energized, the brake is tightened. The relay control circuit is used to control the conduction and disconnection of the relay between the AC power source AC and the rectifier bridge 101, thereby controlling the conduction and disconnection of the brake circuit 102 and the power source. The relay control circuit includes a zero point detection module 111, a trigger 112, a controller 113, a delay device 114 and an actuator 115. The output end of the zero point detection module 111 generates a first level signal A based on the zero point voltage of the AC power supply AC. The trigger 112 generates a second level signal B after being triggered. When the first level signal A is the same as the second level signal B, the output end of the controller 113 outputs a third level signal C. In this way, the delay device 114 is triggered at the zero point voltage of the AC power supply AC. The delay device 114 receives the third level signal C and outputs a fourth level signal D after a preset delay time. The actuator 115 receives the fourth level signal Signal D controls the coil of the relay to be energized so that the contact points of the relay are closed. Since the actuator 115 receives the fourth level signal D, the contact points of the relay are closed after the preset closing time, and the sum of the preset closing time and the delayed delay time is equal to the cycle of the AC power supply AC, the relay can be closed at the zero-point voltage of the AC power supply AC. At this time, the current flowing through the two contacts of the relay is reduced, which can reduce the risk of burning the two contacts of the relay due to the large current flowing through, and thus reduce the probability of the two contacts of the relay sticking, which is beneficial to extending the service life of the relay, avoiding the problem that the brake circuit cannot be controlled, and improving the safety of the brake system.

[0032] Figure 4 A timing diagram of various level signals in a relay control circuit provided in an embodiment of the present application.

[0033] Combined with reference Figure 1 and Figure 4, taking the zero point detection module 111, the trigger 112, the controller 113, the delay device 114 and the actuator 115 as an example, the zero point detection module 111 generates a first level signal A based on the zero point voltage of the alternating current power source AC at the output end, that is, when the voltage of the alternating current power source AC is at zero point, the first level signal A is briefly triggered to be a high level signal. At time t1, the trigger 112 is triggered, and the second level signal B is a high level signal; at the first zero voltage of the alternating current power source AC after time t1, that is, at time t2, the first level signal A and the second level signal B are both high level signals, and at this time, the third level signal C outputted from the output end of the controller 113 is a high level signal; at time t2, the delay device 114 receives the third level signal C and outputs the fourth level signal D as a high level signal after a preset delay time S1; at time t3, the fourth level signal D received by the actuator 115 is a high level signal, and at this time, the actuator 115 controls the coil of the relay to be energized so that the contact point of the relay is closed, and at time t3, after the preset closing time S2, the contact point of the relay is closed, so that the moment t4 when the contact point of the relay is closed is the moment when the voltage of the alternating current power source AC is zero.

[0034] It is understandable that the preset delay time S1 of the delay device 114 may deviate from the actual delay time; or, the preset closing time S2 of the actuator 115 controlling the coil of the relay to be energized so that the contact points of the relay are closed may deviate from the actual closing time, thereby causing the contact points of the relay to be closed near the zero-point voltage of the AC power supply, but the current flowing through the two contacts of the relay is still small, which can still reduce the risk of burning of the two contacts of the relay due to large current flowing through, thereby reducing the probability of the two contacts of the relay sticking together, which is beneficial to extending the service life of the relay, avoiding the problem of the brake circuit being uncontrollable, and improving the safety of the brake system.

[0035] Therefore, the sum of the preset delay time S1 and the preset closing time S2 is equal to the cycle of the AC power supply AC, which means that the sum of the preset delay time S1 and the preset closing time S2 is approximately equal to the cycle of the AC power supply AC, and the sum of the preset delay time S1 and the preset closing time S2 and the cycle of the AC power supply AC can be within an appropriate time difference range.

[0036] In some embodiments, the duration of the second level signal B generated by the trigger 112 after being triggered is less than the cycle of the AC power source AC, and greater than 1 / 2 of the cycle of the AC power source AC. In this way, the first level signal A and the second level signal B can remain the same at the first zero voltage of the AC power source AC after the trigger 112 is triggered, thereby enabling the controller 113 to output the third level signal C.

[0037] refer to Figures 1 to 3In some embodiments, the relay may include a first relay KNB1 and a second relay KNB2. A redundant design of two contactors is provided in the brake system, which can help improve the safety of the brake system and avoid danger caused by failure of a single relay.

[0038] refer to Figure 1 and Figure 3 In one example, the first relay KNB1 is connected between the positive output terminal of the AC power source AC and the positive input terminal of the rectifier bridge 101, and the second relay KNB2 is connected between the negative output terminal of the AC power source AC and the negative input terminal of the rectifier bridge 101.

[0039] refer to Figure 2 In another example, the first relay KNB1 and the second relay KNB2 are connected in series between the positive output terminal of the AC power source AC and the positive input terminal of the rectifier bridge 101 .

[0040] refer to Figure 1 and Figure 2 In an example, when the relay includes a first relay KNB1 and a second relay KNB2, the first relay KNB1 and the second relay KNB2 can be controlled to be turned on and off by an actuator 115.

[0041] refer to Figure 3 In another example, when the relay includes a first relay KNB1 and a second relay KNB2, the delay device may include a first delay device 134 and a second delay device 144, and the first delay device 134 and the second delay device 144 are connected in parallel to the output end of the controller 113; the actuator includes a first actuator 135 and a second actuator 145, and the first actuator 135 is connected between the first relay KNB1 and the first delay device 134, and the second actuator 145 is connected between the second relay KNB2 and the second delay device 144. In this way, the first relay KNB1 and the second relay KNB2 can be controlled by different actuators respectively. After the controller 113 generates the third level signal C, the first delay device 134 and the second delay device 144 can generate different fourth level signals Da and fourth level signals Db after different delay times, so that the first actuator 135 and the second actuator 145 can control the closing of the first relay KNB1 and the second relay KNB2 at different times respectively, and then set the preset delay time more accurately for different relays, so that the first relay KNB1 and the second relay KNB2 can both be closed at the zero point voltage closest to the AC power supply AC.

[0042] In some embodiments, the controller 113 may be an AND gate or a NAND gate. When the controller 113 is an AND gate, the trigger 112, the zero point detection module 111 and the delay 114 are all high-level triggered, and when the first level signal A and the second level signal B are both high-level, the third level signal C generated by the controller 113 is a high-level signal. When the controller 113 is an NAND gate, the trigger 112, the zero point detection module 111 and the delay 114 are all low-level triggered, and when the first level signal A and the second level signal B are both low-level, the third level signal C generated by the controller 113 is a low-level signal.

[0043] In some embodiments, the actuator 115 may be high level triggered or low level triggered.

[0044] Both high level and low level refer to the logarithm of the ratio of two powers or voltages in electrical engineering logic circuits. The high level and low level here are also called relative levels.

[0045] In some embodiments, the delay device 114 includes an even number of inverters connected in series. The inverter can reverse the phase of the input signal by 180 degrees, and the purpose of signal delay can be achieved by repeatedly inverting the third level signal C through an even number of inverters connected in series.

[0046] Figure 5 A schematic diagram of the circuit structure of a specific brake system provided in an embodiment of the present application. Figure 5 The holding brake circuit shown in can be combined with any relay control circuit in the above embodiments to obtain a new embodiment.

[0047] refer to Figure 5The brake circuit includes a step-down circuit 120 and a brake coil 140. The step-down circuit 120 includes: a first switch tube Q1, a first inductor L1, a second switch tube Q2, a first resistor R1, a first diode D1 and a first capacitor C1. The first end of the first switch tube Q1 is connected to the negative output end of the rectifier bridge 101; the first end of the first inductor L1 is connected to the second end of the first switch tube Q1; the first end of the second switch tube Q2 is connected to the second end of the first inductor L1; the first end of the brake coil 140 is connected to the first end of the first diode D1; the first end of the second inductor L1 is connected to the second end of the first diode L1; the first end of the first diode D1 is connected to the first end of the first diode D2; the first end of the first diode D2 is connected to the first end of the first diode L1 ... The first end of the first resistor R1 is connected to the second end of the brake coil 140, and the second end of the first resistor R1 is connected to the positive output end of the rectifier bridge 101; the positive end of the first diode D1 is connected to the second end of the first switch tube Q1, and the negative end of the first diode D1 is connected to the positive output end of the rectifier bridge 101; the first end of the first capacitor C1 is connected to the second end of the first switch tube Q1, and the second end of the first capacitor C1 is connected to the positive output end of the rectifier bridge 101. In the buck circuit 120, the on and off states of the first switch tube Q1 and the second switch tube Q2 are switched by controlling the PWM (Pulse Width Modulation) wave with a variable input duty cycle, and the DC voltage provided by the power supply is converted into an adjustable low voltage output, thereby meeting the power supply requirements of different brake coils. Specifically, the first inductor L1 in the buck circuit 120 converts the current through the magnetic field of the central core of the first inductor L1 into magnetic energy in the on state, and stores the magnetic energy in the first inductor L1. In the disconnected state, due to the self-inductance of the first inductor L1, the magnetic field generates voltage, converts electromagnetic energy into electrical energy, and supplies power to the brake coil 140 through the output end. Therefore, by controlling the on and off states of the first switch tube Q1 and the second switch tube Q2, the periodic conversion and regulation of electrical energy between the first capacitor C1 and the first inductor L1 is achieved, and a stable DC voltage is finally output.

[0048] refer to Figure 5 The brake circuit also includes: a freewheeling circuit 130, which includes a second diode D2 and a transient voltage suppression diode Z1 connected in series, the positive terminal of the second diode D2 is connected to the first end of the brake coil 140, the negative terminal of the second diode D2 is connected to the first end of the transient voltage suppression diode Z1, and the second end of the transient voltage suppression diode Z1 is connected to the second end of the brake coil 140. Through a specific circuit design, the freewheeling circuit 130 can prevent the current from passing through the brake resistor during the contactor pull-in process due to the short circuit of the contact point, thereby reducing the power consumption and heat generation of the resistor. In addition, at the moment of contact point disconnection, by allowing the current to flow through the brake resistor, the voltage when the contact is disconnected can be reduced, thereby extending the service life of the contact point of the contactor. This design improves the efficiency and reliability of the brake circuit by optimizing the current path and reducing unnecessary resistance losses.

[0049] In some embodiments, the brake circuit further includes: a filter capacitor C2, a first end of the filter capacitor C2 is connected to the negative output end of the rectifier bridge 101, and a second end of the filter capacitor C2 is connected to the positive output end of the rectifier bridge 101. The filter capacitor C2 can make the voltage output after filtering a stable DC voltage, and its working principle is that when the output voltage of the rectifier bridge 101 is higher than the voltage of the filter capacitor C2, the filter capacitor C2 is charged, and when the output voltage of the rectifier bridge 101 is lower than the voltage of the filter capacitor C2, the filter capacitor C2 is discharged, and in the process of charging and discharging, the output voltage is basically stable.

[0050] Accordingly, another embodiment of the present application further provides an elevator system, including a brake system as in the embodiment, to improve the safety of the elevator system. For the parts that are the same or corresponding to the previous embodiment, reference may be made to the corresponding description of the previous embodiment, and will not be described in detail below.

[0051] In the brake system provided in the embodiment of the present application, the brake circuit 102 is connected to the AC power source AC through the rectifier bridge 101. The rectifier bridge 101 converts the AC power of the AC power source AC into DC power to be connected to the brake circuit 102. When the brake coil in the brake circuit 102 is energized, the brake is released, and when the brake coil is de-energized, the brake is tightened. The relay control circuit is used to control the conduction and disconnection of the relay between the AC power source AC and the rectifier bridge 101, thereby controlling the conduction and disconnection of the brake circuit 102 and the power source. The relay control circuit includes a zero point detection module 111, a trigger 112, a controller 113, a delay device 114 and an actuator 115. The output end of the zero point detection module 111 generates a first level signal A based on the zero point voltage of the AC power supply AC. The trigger 112 generates a second level signal B after being triggered. When the first level signal A is the same as the second level signal B, the output end of the controller 113 outputs a third level signal C. In this way, the delay device 114 is triggered at the zero point voltage of the AC power supply AC. The delay device 114 receives the third level signal C and outputs a fourth level signal D after a preset delay time. The actuator 115 receives the fourth level signal Signal D controls the coil of the relay to be energized so that the contact points of the relay are closed. Since the actuator 115 receives the fourth level signal D, the contact points of the relay are closed after the preset closing time, and the sum of the preset closing time and the delayed delay time is equal to the cycle of the AC power supply AC, the relay can be closed at the zero-point voltage of the AC power supply AC. At this time, the current flowing through the two contacts of the relay is reduced, which can reduce the risk of burning the two contacts of the relay due to the large current flowing through, and thus reduce the probability of the two contacts of the relay sticking, which is beneficial to extending the service life of the relay, avoiding the problem that the brake circuit cannot be controlled, and improving the safety of the brake system.

[0052] Those skilled in the art will appreciate that the above-mentioned embodiments are specific examples for implementing the present application, and in practical applications, various changes may be made to the embodiments in form and detail without departing from the spirit and scope of the present application. Any person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present application, and therefore the scope of protection of the present application shall be subject to the scope defined in the claims.

Claims

1. A brake system, characterized in that: include: An AC power source having two output terminals; A rectifier bridge, the rectifier bridge comprising two input ends and two output ends, the two input ends of the rectifier bridge being respectively connected to the two output ends of the AC power supply; A brake circuit connected to two output ends of the rectifier bridge; A relay control circuit, the relay control circuit comprising: A zero point detection module, wherein the zero point detection module is connected in parallel to two output terminals of the AC power supply, and the output terminal of the zero point detection module generates a first level signal based on the zero point voltage of the AC power supply; A trigger, wherein the trigger generates the second level signal after being triggered; A controller, the controller comprising two input terminals and one output terminal, one input terminal of the controller is connected to the output terminal of the zero-point detection module, the other input terminal of the controller is connected to the trigger, and when the first level signal is the same as the second level signal, the output terminal of the controller outputs a third level signal; A delay device, the delay device is connected to the output end of the controller, the delay device receives the third level signal and outputs a fourth level signal after a preset delay time; An actuator, the actuator being connected to the delay device; A relay, wherein the coil of the relay is connected to the actuator, and the contact point of the relay is connected between the rectifier bridge and the AC power supply. The actuator receives the fourth level signal and controls the coil of the relay to be energized so that the contact point of the relay is closed. The contact point of the relay is closed after the actuator receives the fourth level signal for a preset closing time, and the sum of the preset closing time and the preset delay time is equal to the period of the AC power supply.

2. The brake system according to claim 1, characterized in that: The relay includes a first relay and a second relay, wherein the first relay is connected between the positive output terminal of the AC power supply and the positive input terminal of the rectifier bridge, and the second relay is connected between the negative output terminal of the AC power supply and the negative input terminal of the rectifier bridge.

3. The brake system according to claim 1, characterized in that: The relay comprises a first relay and a second relay, wherein the first relay and the second relay are connected in series between the positive output terminal of the AC power source and the positive input terminal of the rectifier bridge.

4. The brake system according to claim 2 or 3, characterized in that: The delay device comprises a first delay device and a second delay device, wherein the first delay device and the second delay device are connected in parallel to the output end of the controller; The actuator includes a first actuator and a second actuator, the first actuator is connected between the first relay and the first delay device, and the second actuator is connected between the second relay and the second delay device.

5. The brake system according to claim 1, characterized in that: The controller is an AND gate or a NAND gate.

6. The brake system according to claim 5, characterized in that: The delay device includes an even number of inverters connected in series.

7. The brake system according to claim 1, characterized in that: The brake circuit includes a step-down circuit and a brake coil, and the step-down circuit includes: A first switch tube, wherein a first end of the first switch tube is connected to a negative output end of the rectifier bridge; A first inductor, wherein a first end of the first inductor is connected to a second end of the first switch tube; a second switch tube, wherein a first end of the second switch tube is connected to a second end of the first inductor, and a first end of the brake coil is connected to a second end of the second switch tube; a first resistor, wherein a first end of the first resistor is connected to a second end of the brake coil, and a second end of the first resistor is connected to a positive output end of the rectifier bridge; a first diode, wherein a positive terminal of the first diode is connected to the second end of the first switch tube, and a negative terminal of the first diode is connected to the positive output terminal of the rectifier bridge; A first capacitor, wherein a first end of the first capacitor is connected to a second end of the first switch tube, and a second end of the first capacitor is connected to a positive output end of the rectifier bridge.

8. The brake system according to claim 1 or 7, characterized in that: The brake circuit includes: a freewheeling circuit, which includes a second diode and a transient voltage suppression diode connected in series, the positive terminal of the second diode is connected to the first end of the brake coil, the negative terminal of the second diode is connected to the first end of the transient voltage suppression diode, and the second end of the transient voltage suppression diode is connected to the second end of the brake coil.

9. The brake system according to claim 1 or 7, characterized in that: The brake circuit includes: a filter capacitor, a first end of the filter capacitor is connected to the negative output end of the rectifier bridge, and a second end of the filter capacitor is connected to the positive output end of the rectifier bridge.

10. An elevator system, characterized in that: The invention comprises a brake system as claimed in any one of claims 1 to 9.

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