JP4403614B2 - Elevator braking device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an elevator braking device, and more particularly to an elevator brake control circuit having a double brake structure.
[0002]
[Prior art]
Generally, an elevator braking device is a mechanism that generates a braking force by a frictional force between a shoe and a brake vehicle surface by pressing the shoe with a spring against a brake drum directly connected to a shaft of an electric motor that drives a car. ing. Then, an electromagnetic magnet is provided as a means for releasing the brake, and the brake is released by passing an electric current through the coil of the magnet. A typical elevator is equipped with a set of such electromagnetic brakes, but there are also two sets of electromagnetic brakes that can be operated individually to enhance safety, and is generally called a double brake.
[0003]
In recent years, the weight of a car has been reduced and the inertia around the electric motor has been reduced, and the electric motor and the control device have been reduced in capacity and saved in energy. However, such a low inertia leads to an increase in deceleration when the brake is stopped, which gives passengers discomfort. The standard for setting the braking force of the braking system is as follows: (1) A minimum braking force is required to hold the car in a stationary state with more than the capacity, and (2) During so-called regenerative operation where the load in the traveling direction is negative When an emergency stop occurs, a braking force that pushes up at the terminal floor and does not push down is required.
[0004]
However, if the braking force is secured so as to satisfy this condition, the car deceleration increases when an emergency stop occurs during a so-called power running operation in which the load in the traveling direction is positive. Therefore, it is necessary to specify the upper limit of the braking force, and (3) it is necessary to loosen the braking force so that the emergency stop deceleration during the power running operation is less than the allowable value. In particular, in the case of low inertia, it becomes difficult to satisfy the above (1), (2), and (3) at the same time, and means that can change the braking force depending on conditions is required. Therefore, a method has been proposed in which the above-described double brake is employed and the stop shock is reduced by shifting the operation timings of the two brakes.
[0005]
The relationship between the regenerative operation and power running operation and the load in the car is as shown in FIG. When the weight on the counterweight side is larger than the weight on the car side (light load in the car), the regenerative operation is performed when the car rises and the power running operation is performed when the car descends. Conversely, when the weight on the counterweight side is smaller than the weight on the car side (in-car heavy load), the power running operation is performed when the car is raised, and the regenerative operation is performed when the car is lowered.
[0006]
FIG. 7 is a configuration diagram of a conventional elevator braking device disclosed in, for example, Japanese Patent Laid-Open No. 3-11080. In the figure, 1 is an electric motor for driving a car, 2 is a shaft directly connected to the electric motor 1, 3 is a sheave of a hoisting machine driven by the electric motor 1 through the shaft 2, and 4 is wound around the sheave 3. A rope 5 is a car coupled to one end of the rope 4, a counterweight 6 is coupled to the other end of the rope 4, and 7 is a brake wheel fixed to the shaft 2.
[0007]
Reference numeral 8 denotes an electromagnetic brake, which includes a brake shoe 801 that applies a frictional force to the brake wheel 7, a spring (not shown) that biases the brake shoe 801 against the brake wheel 7, and the brake shoe 801 is pressed against the spring. A plunger 802 and a brake coil 803 for driving the plunger 802 are provided. The brake coil 803 constitutes an electromagnetic magnet. Reference numeral 9 denotes a second electromagnetic brake, and two sets of electromagnetic brakes constitute a double brake. 901 to 903 are the same as 801 to 803.
[0008]
Further, 10 is a DC power source for exciting the brake coils 803 and 903, 11 is a contact that is closed when the brake is released and opened when the brake is operated, 12 is a brake circuit, and 22 and 23 are excitations for the brake coils 803 and 903, respectively. Circuit.
[0009]
The excitation circuit 22 includes a diode 2201, an attenuation time constant adjustment resistor 2202, a current detector 2203, a switch element 2204, and a PWM circuit 2205 in order to control the brake coil current. Similarly to the excitation circuit 22, the excitation circuit 23 includes a diode 2301, an attenuation time constant adjustment resistor 2302, a current detector 2303, a switch element 2304, and a PWM circuit 2305. Reference numeral 18 denotes a control unit that outputs current command values of the brake coils 803 and 903 to the excitation circuits 22 and 23.
[0010]
Next, the operation will be described with reference to FIG. First, when the elevator is activated and the contact 11 is closed, current command values that are sufficient to attract the plungers 802 and 902 are output as shown in FIG. At this time, the PWM circuits 2205 and 2305 operate the switch elements 2204 and 2304, respectively, to control the coil currents in accordance with the difference between the current feedback values detected by the current detectors 2203 and 2303.
[0011]
When the coil current rises as shown in FIG. 8, the plungers 802 and 902 are simultaneously attracted and the brake shoes 801 and 901 are released from the brake wheel 7, so that the driving force of the electric motor 1 is applied to the sheave 3 via the shaft 2. Then, the car 5 is driven.
[0012]
Once the plungers 802 and 902 are sucked, the predetermined value I is equal to or greater than the current (holding current) that can maintain the suction state. ₁ , I ₂ The coil current of the plungers 802 and 902 is reduced to suppress the heat generation of the coil. ₁ And I ₂ Relationship is I ₁ <I ₂ Is set to be.
[0013]
Thereafter, when the brake is stopped due to some abnormality, the contact 11 is immediately opened and power supply from the DC power supply 10 is lost, and the coil current is attenuated while circulating through the diodes 2201 and 2301 and the attenuation time constant adjusting resistors 2202 and 2302. When the current falls below the holding current, the brake operates. At this time, if the decay time constant adjusting resistors 2202 and 2302 are set to the same value, the decay time constant of the coil current is the same. Therefore, the larger the previous current value, the more the current is less than the holding current after the contact 11 is opened. The time to decay is increased, and the time delay until the plunger operates is increased. Therefore, since the brake shoes 801 and 901 are pressed against the brake wheel 7 at different timings, the shock due to the brake stop is alleviated.
[0014]
In addition, if the difference in brake operation time is increased so that only one brake operates during deceleration of the elevator and the second brake operates after the elevator stops, the braking force during deceleration and the The brake force can be set to a different value, and an appropriate brake can be set even in the case of low inertia. However, in the case of an emergency stop during regenerative operation, a large braking force is required so that the brake can be operated simultaneously. ₁ And I ₂ Are set to the same current value.
[0015]
[Problems to be solved by the invention]
As described above, if the difference between the two brake operation times can be set large, it is possible to perform a brake setting that satisfies the conditions (1), (2), and (3) as shown at the beginning. However, in order to have a large difference in the time to reach the holding current, the current value I ₁ And I ₂ It is necessary to set a large difference.
[0016]
For example, if both circuit time constants after the contact 11 is opened are 500 ms, and the time difference at which the coil current decays to the holding current is also 500 ms, then I ₂ Is I ₂ It is necessary to set to about 2.7 times. In this case, I ₂ Becomes a current larger than the holding current, which is not realistic.
[0017]
In addition, there is an example in which the time difference is increased by delaying the operation of the contact 11 using a timer or the like and continuing to supply power to one of the brakes, but the contact 11 is immediately cut off in consideration of a malfunction of the timer. Is desirable.
[0018]
The present invention has been made to solve the above-described problems, and even when the contact point for supplying power to the brake circuit is immediately cut off during an emergency stop of the elevator, the difference in operating time between the two brakes can be increased. An object is to obtain such a brake circuit. And by applying the braking device using such a brake circuit, while stopping an elevator safely, a stop shock is relieved and riding comfort is improved.
[0019]
[Means for Solving the Problems]
The elevator braking device according to the present invention includes a plurality of braking mechanisms, a plurality of electromagnetic magnets provided corresponding to the plurality of braking mechanisms, a brake circuit that supplies power to the plurality of electromagnetic magnets, In an elevator braking device provided with a contact that shuts off the brake circuit from the power source when stopped, the brake circuit deactivates at least one of the plurality of electromagnetic magnets, and at the time of deactivation The deenergization of the remaining electromagnetic magnets is delayed using the released energy.
[0020]
The brake circuit is provided corresponding to each of the plurality of electromagnetic magnets, and includes a plurality of excitation circuits for energizing and deactivating the electromagnetic magnets, and a voltage holding circuit for holding a voltage. At least one of the excitation circuits is connected to the voltage holding circuit with a polarity opposite to that when the electromagnetic magnet is energized when the power is cut off by the contact.
[0021]
Further, the brake circuit has a discharge circuit for discharging the electric charge accumulated in the voltage holding circuit.
[0022]
Furthermore, the excitation circuit includes a switching element connected to the electromagnetic magnet, a reflux circuit for returning the current of the electromagnetic magnet to the voltage holding circuit when the power is cut off by the contact, and turning on and off the switching element. And a control circuit for controlling.
[0023]
The reflux circuit includes a diode.
[0024]
Further, the reflux circuit has a resistance.
[0025]
The elevator braking device according to the present invention includes first and second braking mechanisms, a first brake coil provided corresponding to the first braking mechanism, and corresponding to the second braking mechanism. A second excitation coil, a first excitation circuit for supplying power for exciting the first brake coil, a second excitation circuit for supplying power for exciting the second brake coil, and an elevator And a holding circuit for holding electric energy released by reducing the coil current of the first brake coil, and the first excitation circuit includes the power supply When the power is cut off, the first brake coil is reduced to release electric energy to the holding circuit, and when the power is turned off, the second excitation circuit It is intended to delay the decay of the coil current of the second brake coil using the electrical energy stored in.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram illustrating an elevator braking device according to a first embodiment. In the figure, 1 is an electric motor for driving a car, 2 is a shaft directly connected to the electric motor 1, 3 is a sheave of a hoisting machine driven by the electric motor 1 through the shaft 2, and 4 is wound around the sheave 3. A rope 5 is a car coupled to one end of the rope 4, a counterweight 6 is coupled to the other end of the rope 4, and 7 is a brake wheel fixed to the shaft 2.
[0027]
Reference numeral 8 denotes a first electromagnetic brake. As a braking mechanism, a brake shoe 801 for applying a frictional force to the brake wheel 7, a spring (not shown) for urging the brake shoe 801 against the brake wheel 7, and the brake shoe 801 Has a plunger 802 that pushes against the spring. A brake coil 803 that drives the plunger 802 is also provided. The brake coil 803 constitutes an electromagnetic magnet. Reference numeral 9 denotes a second electromagnetic brake, which constitutes a double brake together with the first electromagnetic brake. 901 to 903 are the same as 801 to 803. The above double brake mechanism is the same as the conventional example.
[0028]
10 is a power source, 11 is a contact, 12 is a brake circuit, and 13 is a first coil excitation circuit that excites the first brake coil 803, and has a function of regenerating the electrical energy of the coil when cut off.
Reference numeral 14 denotes a second coil excitation circuit that excites the second brake coil 903, and has a function of regenerating the electrical energy of the coil when it is shut off.
In other words, the first coil excitation circuit 13 and the second coil excitation circuit 14 have a function of energizing and deactivating the electromagnetic magnet of the first electromagnetic brake 8 or the second electromagnetic brake 9.
A voltage holding circuit 15 holds the voltage for a short time after the contact 11 is cut off and absorbs the regenerative energy regenerated by the first coil excitation circuit 13. The brake circuit 12 includes a first coil excitation circuit 13, a second coil excitation circuit 14, and a voltage holding circuit 15.
[0029]
FIG. 2 is a diagram illustrating an example of a brake circuit according to the first embodiment. In the figure, reference numeral 16 denotes a first excitation circuit for exciting the first brake coil 803, which is composed of 1601 to 1606. Reference numerals 1601 and 1602 denote free-wheeling diodes, 1603 and 1604 switch elements, 1605 a current detector, and 1606 a current control circuit.
The first excitation circuit 16 is a configuration example of the first coil excitation circuit 13 in FIG.
[0030]
Reference numeral 17 denotes a second excitation circuit that excites the second brake coil 903 and includes 1701 to 1706. 1701 to 1706 are the same as 1601 to 1606. The second excitation circuit 17 is a configuration example of the second coil excitation circuit 14 in FIG.
Reference numeral 19 denotes a voltage holding capacitor, and 20 denotes a discharge circuit, which includes a discharge resistor 2001, a switch element 2002, a voltage detector 2003, and a voltage control circuit 2004. The capacitor 19 and the discharge circuit 20 are a configuration example of the voltage holding circuit 15 in FIG.
[0031]
3 and 4 are operation explanatory diagrams of the brake control circuit according to the first embodiment. FIG. 3 is a diagram in the case where the second brake operates with a delay, and corresponds to a case where an emergency stop is made after power running. FIG. 4 is a diagram when the second brake is operated simultaneously, and corresponds to a case where an emergency stop is performed from the regenerative operation. In both figures, (a) shows the time variation of the current flowing through the first brake coil 803 in the lower stage, and the time variation in the current flowing through the second brake coil 903 in the upper stage, and (b) shows the time of the capacitor voltage. Showing change. Hereinafter, the operation of the brake control circuit in this embodiment will be described with reference to FIGS.
[0032]
<Operation at elevator start-up>
When the elevator is activated and the contact 11 is closed, power is supplied to the excitation circuits 16 and 17 and the capacitor 19. Normally, a circuit for preventing an inrush current to the capacitor 19 is provided, but this is omitted in this figure. In the first excitation circuit 16, when the switch elements 1603 and 1604 are turned on, an excitation current flows in the direction of the arrow through the brake coil 803 and attracts the plunger 802. When the first electromagnetic brake 8 is released by attracting the plunger 802, the current control circuit 1606 turns on and off the switch element 1603 based on the coil current value detected by the current detector 1605 to set the coil current value to a predetermined value. To control.
[0033]
In the second excitation circuit 17, the same control as that of the first excitation circuit 16 is performed, the plunger 902 is sucked and held, and the second electromagnetic brake 9 is released. When the two brakes are released, the elevator starts running. The coil current value to be controlled is larger than the holding current, and there is no need to give a difference between the two coil current values as in the conventional example. During this time, the voltage of the capacitor 19 is maintained at substantially the same value as the power supply voltage.
[0034]
<Operation when the elevator stops>
Now, a case where an abnormality occurs during the power running operation and the emergency stop will be described with reference to FIG. In this case, since the unbalanced force due to the load and the braking force due to the brake work in the same direction, it is necessary to delay the operation of one brake in order to prevent the deceleration from increasing.
[0035]
First, the contact 11 is opened immediately after the emergency stop, and power supply from the direct current 10 to the brake circuit is lost. When the current control circuit 1606 turns off the switch elements 1603 and 1604 simultaneously with the opening of the contact 11, the brake coil 803 is connected to the capacitor 19 in the opposite direction. That is, it is connected to the capacitor 19 with the opposite polarity to that when the electromagnetic magnet constituted by the brake coil 803 is energized.
[0036]
Here, since the voltage of the capacitor 19 does not drop immediately, the coil current flows into the positive terminal of the capacitor 19, the electric energy stored in the brake coil 803 is regenerated in the capacitor 19, and the coil current is instantaneously generated. As the voltage attenuates, the voltage of the capacitor 19 slightly increases (see FIGS. 3A and 3B).
Since the current flowing through the brake coil 803 is attenuated, the plunger 802 is immediately released and the brake shoe 801 is pressed against the brake wheel 7 to generate a braking force.
[0037]
On the other hand, in the second excitation circuit 17, even if the contact 11 is opened, the current control circuit 1706 continues to turn on the switch elements 1703 and 1704 and continues current control with the voltage of the capacitor 19. Based on the coil current value detected by the current detector 1705, the current control circuit 1706 controls the switch element 1703 to be turned on and off to maintain the coil current value at a predetermined value. By controlling in this way, the deactivation of the electromagnetic magnet of the second brake 9 is further delayed.
Therefore, the second electromagnetic brake 9 can be continuously released while electric energy remains in the capacitor 19. That is, the second electromagnetic brake 9 does not generate a braking force while electric energy remains in the capacitor 19.
When the electric energy of the capacitor 19 is lost, the plunger 902 is released and the brake shoe 901 is pressed against the brake wheel 7 to generate a braking force.
In the above description, the current control circuit 1706 controls the switch element 1703 to be turned on and off to maintain the coil current value at a predetermined value. However, the switch element 1703 is not necessarily turned on and off. May be. In this case, although the demagnetization of the electromagnetic magnet of the second brake 9 is slightly faster than in the case of on / off control, the operation of the second electromagnetic brake 9 is delayed compared to the first electromagnetic brake 8. I can.
[0038]
In other words, when the brake circuit 12 is disconnected from the power source, the coil current is reduced from the brake coil 803 of the first electromagnetic brake 8 to release electric energy to the voltage holding circuit 15 and to deenergize the electromagnetic magnet. . The decay of the coil magnet 903 of the second brake 9 is delayed by the electrical energy stored in the voltage holding circuit 15, thereby deactivating the electromagnetic magnet of the second brake 9.
[0039]
Thereby, since the operation delay of the second electromagnetic brake 9 with respect to the first electromagnetic brake 8 can be increased, the second car brake slowly decelerates and stops by the first electromagnetic brake 8 before the second electromagnetic brake 8 stops. The electromagnetic brake 9 can be operated to generate a sufficient stationary holding force.
Further, since the coil current of the brake coil 803 of the first electromagnetic brake 8 is positively released, the operation disclosure of the first electromagnetic brake 8 can be shortened, and the time for applying the braking torque after the contact 11 is opened is conventionally set. Than before. Therefore, the stop distance can be shortened.
Furthermore, in the present embodiment, the supply of external power is cut off in an emergency, so that the first electromagnetic brake 8 can be operated reliably while the operation of the second electromagnetic brake 9 is delayed.
[0040]
In this configuration, an excitation circuit having a regeneration function is employed in both the excitation circuits 16 and 17, so that the second electromagnetic brake 9 is operated immediately and the first electromagnetic brake 8 is operated after stopping. It can also be made. Furthermore, the mechanical stress applied to the shaft can be reduced by replacing the brake that is initially operated every emergency stop.
[0041]
Next, a case where an abnormality occurs during the regenerative operation and the emergency stop will be described with reference to FIG. In this case, since the unbalance force due to the load and the braking force due to the brake work in opposite directions, it is necessary to immediately operate the two brakes in order to stop the elevator at a predetermined distance.
[0042]
The elevator starts traveling in the same manner as in FIG. 3, and immediately after the emergency stop, the contact 11 is opened and power supply from the DC power supply 10 is lost. When the current control circuits 1606, 1706 turn off the switch elements 1603, 1604, 1703, 1704 simultaneously with the opening of the contact 11, the brake coils 803, 903 are connected to the capacitor 19 in the opposite direction. Here, since the voltage of the capacitor 19 does not drop immediately, the coil current of the brake coils 803 and 903 flows into the plus terminal of the capacitor 19 in the same manner as described above, and the electric energy of the two brake coils 803 and 903 is regenerated in the capacitor. . Then, since the coil current flowing through the brake coils 803 and 903 rapidly decays, both brakes operate immediately. For this reason, the car can be stopped safely without being pushed up or pushed down even during an emergency stop during regenerative operation.
[0043]
In this case, since electric energy is regenerated from the brake coils 803 and 903, the voltage rise of the capacitor 19 is relatively large. When the circuit voltage is high, the life of the connected device is shortened, and the worst damage may occur. Therefore, the voltage of the capacitor 19 is detected by the voltage detector 2003, and the voltage control circuit 2004 operates the switch element 2002 so as to obtain a predetermined voltage, and discharges the electric charge to the discharge resistor 2001. Further, after the elevator stops, the residual charge of the capacitor 19 is completely discharged to prevent electric shock.
[0044]
Since no power is supplied to the brake circuit 12 from the outside after an emergency stop, if the electric energy stored in the two brake coils 803 and 903 and the capacitor 19 is consumed, the current of the brake coil becomes zero. For this reason, even if some abnormality occurs in the operation of the circuit, both brakes can be operated reliably in a predetermined time.
[0045]
Further, the switch elements 1603, 1604, 1703, and 1704 in this embodiment keep the coil currents of the brake coils 803 and 903 constant while attracting the plungers 802 and 902 and releasing the electromagnetic brakes 8 and 9, respectively. In addition, the circuit can be simplified because it functions as a switch for releasing the coil current of the brake coils 803 and 903 during an emergency stop.
[0046]
Embodiment 2. FIG.
In the first embodiment, while the electromagnetic brake 8 operates and the electromagnetic brake 9 is released, in the second excitation circuit 17, the current control circuit 1706 turns on the switch elements 1703 and 1704 even if the contact 11 is opened. Continuously, current control is continued by the voltage of the capacitor 19. Based on the coil current value detected by the current detector 1705, the current control circuit 1706 controls the switch element 1703 to be turned on and off to maintain the coil current value at a predetermined value.
The coil current value controlled by the current control circuit 1706 may be controlled so as to increase the command current value in accordance with an increase in the capacitor voltage.
In this case, in addition to the same effects as in the first embodiment, the power consumption in the brake coil 903 increases, so that an increase in the capacitor voltage can be suppressed.
[0047]
Embodiment 3 FIG.
In the first embodiment, the return circuit is composed of only a diode, but the same effect can be obtained by inserting a resistor for adjusting the decay time constant in series with the diode. In this case, in addition to the same effects as in the first embodiment, the current decay time can be adjusted, so that the difference in operation timing between the two brakes can be changed. Moreover, the consumption of a part of the regenerative energy can be consumed by the resistor, so that an increase in the capacitor voltage can be suppressed.
[0048]
Embodiment 4 FIG.
FIG. 5 shows the fourth embodiment. In FIG. 5, reference numeral 21 denotes an exciting circuit for the brake coil 903, and the regenerative function is omitted from the second exciting circuit 17 in FIG. Other reference numerals are the same as those in FIGS. In this case, there is a difference in operation timing when the electromagnetic brake 8 and the electromagnetic brake 9 are operated simultaneously. That is, in this embodiment, the operation timing of the brake 21 corresponding to the brake coil 903 is slightly delayed as compared with the case where the first and second excitation circuits 16 and 17 are provided with the regeneration function in FIG. However, the same effect as in the first embodiment can be obtained. Furthermore, it can be configured at low cost by reducing the number of parts.
[0049]
Embodiment 5 FIG.
In the first embodiment, the discharge circuit 20 is provided to discharge the voltage of the capacitor 19, but a configuration without the discharge circuit 20 as shown in FIG. 5 is also conceivable. In this case, the capacitor 19 constitutes the voltage holding circuit 15. In this case, if a current that does not attract the plunger again with the excitation circuits 16 and 21 is caused to flow through the brake coil, voltage increase and residual charge due to immediate operation of both brakes can be prevented. In addition, the structure without a discharge circuit in FIG. 2 can be considered similarly.
[0050]
Embodiment 6 FIG.
In the above description of the first to fifth embodiments, the case where the double brake has two braking mechanisms has been described, but a braking device having three or more braking mechanisms is also conceivable. In this case, it is possible to adjust the braking force during deceleration in multiple stages by changing the grouping into those that immediately de-energize and those that delay de-energization, and further reduce the stop shock. it can.
By the way, although the brake device of the type that presses the brake shoe against the brake wheel 7 for braking has been described, it goes without saying that the brake device can be used for another type of brake device using an electromagnetic magnet (for example, a disc brake).
In addition, all the above-mentioned embodiment shows one form of this invention, You may combine these embodiment mutually.
[0051]
【The invention's effect】
The elevator braking device according to the present invention includes a plurality of braking mechanisms, a plurality of electromagnetic magnets provided corresponding to the plurality of braking mechanisms, a brake circuit that supplies power to the plurality of electromagnetic magnets, In an elevator braking device provided with a contact that shuts off the brake circuit from the power source when stopped, the brake circuit deactivates at least one of the plurality of electromagnetic magnets, and at the time of deactivation Since the deenergization of the remaining electromagnetic magnets is delayed using the released energy, the operation timing of the plurality of braking devices can be shifted, and the stop shock of the elevator can be mitigated.
[0052]
The brake circuit is provided corresponding to each of the plurality of electromagnetic magnets, and includes a plurality of excitation circuits for energizing and deactivating the electromagnetic magnets, and a voltage holding circuit for holding a voltage. At least one excitation circuit among the excitation circuits is connected to the voltage holding circuit with a polarity opposite to that when the electromagnetic magnet is energized when the power is cut off by the contact, and thus deenergizes the electromagnetic magnet in a short time. It is possible to shorten the operation time of the braking device that operates first.
[0053]
Furthermore, since the brake circuit has a discharge circuit that discharges the electric charge accumulated in the voltage holding circuit, the voltage of the voltage holding circuit can be suppressed within an appropriate range.
[0054]
Furthermore, the excitation circuit includes a switching element connected to the electromagnetic magnet, a reflux circuit for returning the current of the electromagnetic magnet to the voltage holding circuit when the power is cut off by the contact, and turning on and off the switching element. Since the control circuit for controlling is provided, the excitation circuit can be configured with a simple configuration.
[0055]
Further, since the reflux circuit includes a diode, the reflux circuit can be easily configured.
[0056]
Further, since the reflux circuit has a resistance, the operation timing of the braking device can be adjusted by adjusting the resistance value.
[0057]
The elevator braking device according to the present invention includes first and second braking mechanisms, a first brake coil provided corresponding to the first braking mechanism, and corresponding to the second braking mechanism. A second excitation coil, a first excitation circuit for supplying power for exciting the first brake coil, a second excitation circuit for supplying power for exciting the second brake coil, and an elevator And a holding circuit for holding electric energy released by reducing the coil current of the first brake coil, and the first excitation circuit includes the power supply When the power is cut off, the first brake coil is reduced to release electric energy to the holding circuit, and when the power is turned off, the second excitation circuit Using stored electrical energy for delaying the attenuation of the coil current of the second brake coil, can shift the operation timings of a plurality of braking devices, it can be alleviated elevator stop shock.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of an elevator braking apparatus according to a first embodiment.
FIG. 2 is a brake circuit diagram according to the first embodiment.
FIG. 3 is a diagram showing an operation after a power running operation in the first embodiment.
FIG. 4 is a diagram showing an operation after a regenerative operation in the first embodiment.
FIG. 5 is a brake circuit diagram according to a fourth embodiment.
FIG. 6 is a diagram showing a relationship between regenerative operation, power running operation, and car load.
FIG. 7 is a configuration diagram showing a conventional elevator braking device.
FIG. 8 is a diagram showing a conventional brake current waveform.
[Explanation of symbols]
7 brake wheel, 8 first electromagnetic brake, 9 second electromagnetic brake, 11 contact, 12 brake circuit, 13 first coil excitation circuit, 14 second coil excitation circuit, 15 voltage holding circuit, 16 first Excitation circuit, 17 Second excitation circuit, 20 Discharge circuit, 1601, 1602 Diode, 1603, 1604 Switch element, 1606 Current control circuit, 1701, 1702 Diode, 1703, 1704 Switch element, 1706 Current control circuit, 2202 Decay time constant Adjustment resistor.

Claims (6)

A plurality of braking mechanisms;
A plurality of electromagnetic magnets provided corresponding to the plurality of braking mechanisms,
A brake circuit for supplying power to the plurality of electromagnetic magnets;
In an elevator braking device provided with a contact for disconnecting the brake circuit from the power supply when the elevator is stopped,
The brake circuit is
A plurality of excitation circuits provided corresponding to the plurality of electromagnetic magnets, respectively, for energizing and deactivating the electromagnetic magnets;
A voltage holding circuit for holding a voltage;
Consisting of
At least one of the plurality of excitation circuits is connected to the voltage holding circuit with a polarity opposite to that when the electromagnetic magnet is energized when the power is cut off by the contact, and deenergizes the electromagnetic magnet. In addition, a braking apparatus for an elevator, characterized in that the deactivation of other electromagnetic magnets is delayed based on the energy released during deactivation. 2. The elevator braking device according to claim 1 , wherein the brake circuit includes a discharge circuit that discharges electric charges accumulated in the voltage holding circuit. The excitation circuit includes a switching element connected to the electromagnetic magnet, a reflux circuit that returns the current of the electromagnetic magnet to the voltage holding circuit when the power is cut off by the contact, and a control that controls on / off of the switching element. braking device for an elevator according to claim 1 or claim 2, characterized in that a circuit. The elevator braking device according to claim 3 , wherein the return circuit includes a diode. The elevator braking device according to claim 4 , wherein the return circuit has a resistance. First and second braking mechanisms; a first brake coil provided corresponding to the first braking mechanism; a second brake coil provided corresponding to the second braking mechanism;
A first excitation circuit for supplying a power source for exciting the first brake coil;
A second excitation circuit for supplying a power source for exciting the second brake coil;
A contact for shutting off the power supply when the elevator stops,
A holding circuit for holding electric energy released by reducing a coil current of the first brake coil;
The first excitation circuit causes the holding circuit to release electrical energy by reducing a coil current of the first brake coil when the power source is cut off, and the second excitation circuit An elevator braking apparatus characterized in that when the power is cut off, the decay of the coil current of the second brake coil is delayed using the electrical energy stored in the holding circuit.

Images