JPH0214273B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD OF THE INVENTION This invention relates to an improvement in a device for controlling the speed of an elevator.

[Prior art]

To control the speed of an electric motor that drives an elevator car, so-called negative feedback control is used, which is controlled using a deviation signal between a speed command signal and a speed signal of the electric motor. In order to stably and accurately control the speed of the car, a device having frequency characteristics is inserted to give the control system delay characteristics. Furthermore, in order to improve the characteristics at the time of starting, it is also used to add a starting compensation signal having a constant value at the time of starting to the normal speed command signal. These are disclosed in, for example, Japanese Unexamined Patent Publication No. 56-161270, and are shown in FIGS. 1 and 2.

In Fig. 1, 1 is a speed command generator that generates a speed command signal V _p that commands the speed of an elevator car (not shown), and 2 is a starting compensation signal V with a constant value to improve the dynamic characteristics at the time of starting. ₃ is an adder that adds the speed command signal V _p and the start command signal V _pst , 3 a is the addition signal, and 4 detects the rotational speed of the induction motor 8 to be output later. A rotational speed/voltage converter that converts the voltage into a voltage and generates a speed signal _Vt , 5 is an adder that adds the addition signal 3a and the speed signal _Vt , 5a is its output as a deviation signal, and 6 stabilizes the car with accuracy. A device that has the frequency characteristics necessary for high speed control and adds a delay operation to the deviation signal 5a, and 6a is the output signal,
7 is a thyristor amplifier whose firing angle is controlled according to the magnitude of the input signal 6a, and 8 is an induction motor whose applied voltage is controlled according to the output of the thyristor amplifier 7. (not shown) is driven.

In FIG. 2, reference numeral 11 denotes an operational amplifier, the inverting terminal (-) of which is connected to the adder 5 through a resistor 12, and the non-inverting terminal (+) being grounded through a resistor 13. A resistor 14 is connected between the inverting terminal (-) and the output terminal, as well as a capacitor 15 and a resistor 1.
6 series circuits are also connected.

That is, when a starting command is given to the car, the speed command signal V _p and the starting compensation signal V _pst are added together in an adder 3 , and the added signal 3 a and the speed signal V _t are added together in an adder 5 . The deviation signal 5a is then sent to a device 6 having frequency characteristics, and the capacitor 15
and is applied to the thyristor amplifier 7 with a time delay determined by the resistor 16. This startup compensation signal V _pst
is set to prevent the car from jumping out at startup due to the difference in weight between the car and the counterweight, and acts as a braking command signal. Therefore, the output signal 6a of the device 6 having frequency characteristics also becomes a braking command signal.

However, even if the starting command generating device 2 is provided to compensate for the riding comfort at the time of starting, it is difficult to ensure a comfortable riding comfort over the entire load of the car. For example, in the case of a no-load rise, jump-out at startup is prevented because the output signal 6a is a braking command, but when accelerating, the output signal 6a gradually switches from a braking command to a power running command, so the braking command is small. However, the car is pulled by the counterweight, which worsens the riding comfort. This is the output signal 6a
Device 6 that maintains frequency characteristics even after the cage is activated
This is because the braking command cannot be suddenly switched to the power running command because of the delay operation added by the start compensation signal V pst, and the load compensation using the start compensation signal V _pst is not working properly.

[Summary of the invention]

This invention is intended to improve the above-mentioned problems, and in the case of unloading operation (described later), by canceling the delay function of the device that has frequency characteristics at the time of car startup, the elevator ride comfort at the time of startup can be improved. The purpose of the present invention is to provide a speed control device.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 3 to 5.

In FIG. 3, reference numeral 21 is an operating state detection device that is installed in the car and detects the operating state from the load inside the car and the operating direction, and sends a corresponding signal to the start command generator 2. Reference numeral 22 is a device that detects the rotational speed of the electric motor 8. A start confirmation device 23 emits a start completion signal when the start of the car is completed, and when the start completion signal is input, the start confirmation device 23 cancels the delay function of the device 6 having frequency characteristics depending on the operating state of the car and restarts the above operation after a predetermined short period of time has elapsed. This is a frequency characteristic cancellation device that restores the delay function.

In Figures 4 and 5, P and N are DC power supplies, 21
a is opened when the operating state detection device 21 detects a so-called lifting operation such as a heavy load raising operation (an operation in which either the car or the counterbalance, whichever is heavier, is raised); Operation status detection relay contact 22a closes when operation (operation of lowering either the car or the counterweight, whichever is heavier) is detected, and 22a is a start completion detection relay contact that closes when the start confirmation device 22 detects the completion of start of the car. The relay contact 23A is a frequency characteristic canceling relay, and is connected to power supplies (+) and (-) through a series connection of contacts 21a, 22a, and 25b (described later). 23Aa and 23Ab are normally open contacts of the frequency characteristic cancellation relay 23A, and the contact 23Aa is connected between one end of the capacitor 15 and the ground. 2
4 is a run command relay contact that closes when a run command is issued and opens when the car stops; 25 is a frequency characteristic return relay, which is connected to power supplies (+) and (-) via contacts 23Ab and 24. There is. 25a is a normally open contact of the frequency characteristic return relay 25, and contact 23
It is connected in parallel with Ab, and 25b is also a normally closed contact. Other than the above, the configuration is the same as in FIGS. 1 and 2.

Next, the operation of this embodiment will be explained in the case of lowered load operation.

Before starting the car, the operating state detecting device 21 detects that the load in the car is in a lowered state, and transmits the signal to the starting command generating device 2. Therefore,
In the starting command generating device 2, the starting compensation signal V _pst for unloading is set in a direction in which the car does not jump out, that is, as a braking command signal. This activation command signal
As described above, V _pst is added to the speed command signal V _t , the deviation signal 5a from the speed signal V _t becomes a braking command signal, and the subsequent output signal 6a of the device 6 having frequency characteristics also becomes a braking command signal. , which functions to prevent the basket from flying out. When the operating state detection device 21 detects an unloaded load, the operating state detection relay contact 21a closes, but since the startup completion detection relay contact 22a is still open, the frequency characteristic cancellation relay 23A remains deenergized. , contact 23Aa is open. Therefore, the frequency characteristics are in a non-cancelled state. after that,
A starting command is given to the car, but as mentioned above, the starting compensation signal V _pst causes the brake (not shown) to
Even after the brake is released, the output signal 6a of the device 6 having frequency characteristics remains a braking command signal.
Without the car jumping out, the output signal 6a gradually shifts to the power running command side due to the rise of the speed command signal _Vp , the braking force is reduced, and the car starts.

When the car is started, the start completion detection relay contact 22a closes, and P-21a-22a-25b
-23A-N circuit, frequency characteristic cancellation relay 2
3A is energized and contacts 23Aa and 23Ab are closed. By closing contact 23Aa, capacitor 15
is discharged, the delay function of the output signal 6a of the circuit 6 having frequency characteristics is canceled, the output signal 6a changes stepwise, and the braking command is instantaneously switched to the power running command. On the other hand, since the travel command relay contact 24 is closed, when the contact 23Ab is closed,
The frequency characteristic return relay 25 is energized by the circuit P-23Ab-24-25-N, and the contact 25a
It maintains itself by closing. Further, since the contact 25b is opened, the frequency characteristic cancellation relay 23 is deenergized, and the contacts 23Aa and 23Ab are opened. Contact 2
By opening 3Aa, the delay function of the device 6 having frequency characteristics is restored again. This prevents the car from jumping out, and when the car completes startup, the braking command is instantly switched to the powering command, and after the switch, the delay function of the device 6 with frequency characteristics is instantly restored, so that This makes it possible to control acceleration with extremely good ride comfort. When the car stops, the running command relay 24 is opened, so the frequency characteristic return relay 25 is deenergized, the contact 25a is opened, and the contact 25b is closed, returning to the initial state.

Note that during loading operation, the operating state detection relay contact 21a is open, so the delay function of the device 6 having frequency characteristics is not canceled. That is, during load-lifting operation, since the start-up compensation signal V _pst is a power running command signal, there is no need to cancel the delay function after the start-up is completed.

〔Effect of the invention〕

As described above, in the present invention, the addition signal of the elevator speed command signal and start compensation signal is compared with the speed signal, and the deviation signal is outputted via a device having frequency characteristics. After the car completes startup, the delay function of the device with the above frequency characteristics is canceled, making it possible to instantly switch from a braking command to a powering command, maintaining good car ride comfort from startup to acceleration. can do.

[Brief explanation of drawings]

FIG. 1 is a block circuit diagram showing a conventional elevator speed control device, FIG. 2 is a circuit diagram of a device having the frequency characteristics shown in FIG. 1, and FIG. 3 is an embodiment of an elevator speed control device according to the present invention. 4 is a circuit diagram of a device having the frequency characteristics of FIG. 3 and a frequency characteristic canceling device, and FIG. 5 is a circuit diagram for operating the frequency characteristic canceling device of FIG. 4. DESCRIPTION OF SYMBOLS 1...Speed command generation device, 2...Start command generation device, 3...Adder, 4...Rotation speed/voltage conversion device, 5...Adder, 6...Device having frequency characteristics, 7... Thyristor amplifier, 8... Induction motor, 21... Operating state detection device, 22... Starting confirmation device, 23... Frequency characteristic canceling device, 23A...
...Frequency characteristic cancellation relay, 25...Frequency characteristic recovery relay. Note that the same reference numerals in the figures indicate the same parts.

Claims (1)

[Claims] 1 Add the speed command signal and the starting compensation signal that is output only at starting, and output the deviation signal between this addition signal and the speed signal of the motor with a delay via a device with frequency characteristics, and use this output to control the speed of the motor. In an apparatus in which a combination of a car and a counterweight is raised and lowered by varying the applied voltage and controlling the speed, it is detected that the operation is to lower either the car or the counterweight, whichever is heavier. An operating state detection device, and a delay canceling device that cancels the delay function of the device having the frequency characteristics when the operation state detection device operates and the starting of the car is completed, and immediately returns the delay function. Features: Elevator speed control device.