JPS606278B2 - elevator control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an elevator control device.

Highly accurate automatic control is achieved by a speed control system that detects the speed of the elevator car, provides negative feedback, and compares this with a speed command signal.

When the car is stopped, the electric motor is restrained by the brake, and when the car is started, the brake is released and the electric motor is released. However, due to fluctuations in the number of players in the car, the weight of the car and the weight of the counterweight may become inconsistent. In such a case, when the brake is released, the car will instantly move either up or down, and passengers will feel a shock, which will significantly impair ride comfort. Therefore, in general, an in-car load detection device is provided, and a so-called scale starting device is used that uses the output of the device to supply a current to the electric motor in advance to cancel out the unbalanced torque caused by the difference in weight between the car and the counterweight, and then releases the brake. being explored. However, this scale starting device has multiple configurations and is expensive. It has also been considered to differentiate the speed signal of the car using a differentiating circuit to obtain an acceleration signal, which is then fed back as a negative feedback, thereby alleviating the impact caused by the unbalanced torque. That is, when the car attempts to move due to unbalanced torque, this acceleration feedback circuit serves to stop the car by giving negative feedback to the zero movement. However, in order to substantially eliminate the movement of the car by this acceleration feedback, it is necessary to increase the gain of the acceleration control circuit formed through the acceleration feedback circuit considerably and to increase the response time of the acceleration control circuit. There is a point. On the other hand, this gain is controlled by the stability of the elevator speed control system. The reality is that the above gain cannot be made very high, especially since it interferes with the main element system that supports the car and causes the control system to oscillate. 0 This invention solves the above-mentioned problems, and aims to provide an elevator control device that can prevent oscillation of the control system even if the gain of the acceleration control circuit when the car is stopped is sufficiently high, and that can be constructed at low cost. shall be.

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 1 to 4.

In Fig. 1, 1 is a speed command generation circuit, la is its output, that is, a speed command signal, 2a to 2c are adders, 3 and 4 are amplifiers, 5 is a field power control circuit, and 6 is the field of the DC generator. , 7 is the same armature (driving motor is omitted), 8 is the armature of the DC motor that receives power from armature 7 (Kaiji is omitted), and 9 is the power generator for the speedometer driven by armature 8. 9a is its output or speed signal, 10 is a differential circuit, 10a is its output or acceleration signal, 11 is a shunt, 12 is a current detection circuit, and 13 is a sheave of the hoisting rock driven by the armature 8. , 14 is a deflection wheel, 15 is a main element wound around the sheave 13 and the deflection wheel 14, and a cage 16 and a counterweight 17 are connected.

Reference numeral 18 denotes a friction type brake that controls or releases a brake wheel (not shown) directly connected to the armature 81.

In Figure 2, A is an operational amplifier, R, , R2 are resistors, and B is a photocoupler, which consists of a light-emitting diode D and a corresponding photosensitive element CdS whose resistance changes depending on the amount of light. , the photosensitive element CdS is connected between the input and output of the operational amplifier A.

R3 and R4 are resistors, C is a capacitor, E is brake 1
The brake release command relay contact which opens when the release command of 8 is issued, and 10V is the semiconductor positive power supply. Photocoupler B,
Resistors R3, R4, capacitor C, contact E, and power supply +V
The gain gradual reduction circuit 4A is configured by, for example,
Yojiro Yokoi, “Linear IC Practical Circuit Manual” (April 20, 1975), Radio Gijutsu Co., Ltd., p. 158Figure 4
．． 53. Speed signal 9a is compared with speed command signal la in adder 2a, and these deviation signals are amplified in amplifier 3. Further, the acceleration signal 10a is compared with the output signal of the amplifier 3 in the adder 2b, and the deviation signal thereof is amplified in the amplifier 4. Further, the output of the shunt 11 is detected by the current detection circuit 12, the output, that is, the current signal is compared with the output signal of the amplifier 4 in the adder 2c, and the deviation signal is inputted to the field control circuit 5.
The field 6 is controlled by the output signal. As a result, the voltage applied to the armature 8 is adjusted, and its speed, that is, the speed of the car 16, is automatically controlled. Note that when the car 16 is stopped, the brake 18 restrains the armature 8, and the car 16
The brake 18 is gradually loosened as the armature 8 is started, and the armature 8 is gradually released. Now, the gain g of the amplifier 4 is expressed by the following equation, where the resistance of the photosensitive element C is Rc.

Ro g=When the ear cage 16 is stopped, the brake release command relay point E is closed, so the current 1 passing through the light emitting diode D becomes zero and the resistance Rc becomes large.

Therefore, in this case, the gain g is higher than the steady gain &,
The gain seal is set to a degree that can alleviate the impact caused by unbalanced torque. Brake 108 begins to release the brake vehicle from time to. On the other hand, since contact E is opened, current 1 gradually increases due to the action of the time delay circuit of capacitor C. Accordingly, the amount of light from the light emitting diode D increases, and the resistance Rc gradually decreases. with this,
The gain of the amplifier 4 begins to decrease toward the steady gain g2. The brake 18 is completely released at an intermediate time t, releasing the armature 8. During the time to-t, the brake 18
Since the armature 8 is still restrained and the gain of the acceleration control circuit is high, the shock at startup due to unbalanced torque is negligibly small.

On the other hand, regarding interference with the main element system, since the brake 18 does not completely release the armature 8, even if the gain of the acceleration control circuit is high, the gain of the main element system is reduced due to the frictional force of the brake 18. The increase is controlled and does not lead to oscillation.

Even if oscillation occurs, the time is short and can be ignored, and the steady gain g2 is returned immediately, so the oscillation does not grow and the stability of the system is maintained.

Thereafter, at time t when the brake 18 releases the armature 8, the speed command signal la is input, and the car 16 starts running. Thereafter, at time t2, the gain of the amplifier 4 becomes a steady-state gain saddle. If the above-mentioned horizontal configuration is used, the elevator can be controlled stably without starting shock due to unbalanced torque without using expensive equipment such as an in-cage load detection device. 5 and 6 show other embodiments of the present invention, where F is a DC current transformer, 18A is a brake coil that is energized when the brake 18 is applied, and E2 is a brake coil that is energized when the brake 18 is released. The brake release command relay to close and the two rivers are DC power sources.

Other than the above, it is the same as in FIG. 2. When the car 16 is stopped, the brake release command relay point E2 is open, so no current flows through the brake coil 18A, and the current 1 flowing through the light emitting diode D is zero.

When the contact E2 closes and current begins to flow through the brake coil 18A, the output of the DC current transformer F, that is, the current 1, gradually increases, and the gain g gradually decreases as in the case of FIG. 4.
In this way, the gain of the amplifier 4, that is, the acceleration control circuit, can be changed in accordance with changes in the brake current, that is, changes in the brake torque. As explained above, in this invention, ``the gain of the acceleration control circuit in the speed control system of the elevator is set to be larger when the car is stopped than when it is running, so that when the car is started, the gain is gradually reduced as the brake releases the electric motor. As a result, it is possible to construct a stable control device at low cost, in which no impact is generated due to unbalanced torque, and the speed control system does not oscillate.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of an elevator control device according to the present invention, and FIG. 2 is a circuit diagram of the amplifier 4 shown in FIG.
3 and 4 are diagrams explaining the operation of FIGS. 1 and 2, FIG. 5 is a diagram showing another embodiment of the invention, and is a circuit diagram of the amplifier 4 in FIG. 1, and FIG. FIG. 5 is an explanatory diagram of the operation of FIG. 5; 1...Speed command generation circuit, 2a to 2c...Adder, 3, 4...Amplifier, 4A...Gain gradual reduction circuit, 5...World energy control circuit, 6... Field of DC generator, 7... Armature on the same left, 8... Armature of DC motor, 9... Generator for speedometer, 10... Differential circuit , 13... Steel car, 15... Principal element " 18
...Friction brake. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1 The car drive electric motor is controlled by a speed control system,
and an acceleration control circuit formed in the speed control system via a circuit that negatively feeds back a signal corresponding to the acceleration of the electric motor, which restrains the electric motor when the car is stopped and when the car is started. In the vehicle having a brake for releasing the electric motor, the gain of the acceleration control circuit is set to be larger when the car is stopped than when the car is running, and the gain of the acceleration control circuit is set to be larger when the car is stopped than when the car is running. A control device for an elevator, comprising: a gain gradual reduction circuit that gradually reduces the gain as the electric motor is released.