JPH0216678B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an overall operation control device that can collectively operate a large number of electric motors, and particularly to an improvement in a failure detection circuit that detects a failure and stops the electric motor.

As shown in FIG. 1, this type of conventional device mainly includes a starting circuit 10 provided for each electric motor, a starting control circuit 20 provided for each electric motor or a series of electric motors, and a starting control circuit 20 provided for each electric motor or a series of electric motors. While giving an operation command signal to the startup control circuit 20 of
It is comprised of a general control circuit 30 that cancels the operation command signal and stops the electric motor in the event of a failure while checking the operating state.

Among these, the starting circuit 10 includes a no-fuse breaker 11 and an electromagnetic contactor 12 connected in series to the motor 1.
A thermal relay 12 as an overcurrent relay is inserted into the power supply circuit of the power supply circuit, and is further provided on two power supply lines forming the power supply circuit.

The start control circuit 20 also includes a drive command relay 2 that is activated by a drive command signal from the overall control circuit 30.
1, whether the electric motor 1 is operated independently regardless of other systems, or whether it is operated by the general control circuit 30;
Alternatively, a mode selection switch 22 that can freely select an operation mode to stop, relays 23 and 24 that operate according to the operation mode of this selection switch 22, and a mode selection switch 22 that operates the electromagnetic contactor 12 when the relay 23 operates. The thermal relay 13 includes a relay 26 that is activated, and a relay 25 that is activated when the switching contact 13-c of the thermal relay 13 is switched. Note that an auxiliary contact 11-a of the no-fuse breaker 11 is inserted in series with relays 23 and 24 that operate according to the operating mode of the selection switch 22.

On the other hand, the general control circuit 30 is provided for each individual motor or a series of motors, and includes a main circuit 31 that outputs start command signals and stop command signals for these motors, and controls the operation of the relay 26, that is, the contact 26-a. An OR circuit 32 which uses the closing as an operation confirmation signal and determines whether either the operation confirmation signal or the start command signal has been output;
The output signal of the circuit 32, the interlocking condition signal when the relay 24 is activated, that is, when the contact 24-a is closed, and the interlocking condition signal when the relay 25 is activated, that is, the contact 25-
Overload (failure) signal “H” when a is open
It is provided with an AND circuit 33 that outputs a driving command signal when a level signal is output and an interlock signal indicating that interlock with other systems is established, and when all conditions are satisfied. .

In FIG. 1, to operate the electric motor 1, first turn on the no-fuse breaker 11, then turn the mode selection switch 22 to "LOCAL" and "OFF".
Switch to either “CENTER”, but since this invention is related to general operation, here it is always switched to “CENTER”.
It is assumed that the CENTER side has been replaced. In addition,
When the north fuse breaker 11 is turned on, its auxiliary contact 11-a is closed, so the relay 24
works.

At this time, the contact 26-a is opened and the contact 24-a is opened.
Since a is closed and contact 25-a is open,
The operation confirmation signal will not be output, the interlock condition signal will be output, and the overload signal will not be output. Then, when a start command signal is output from the main circuit 31 with the interlock condition satisfied,
Operation command signal φ is output from the AND circuit 33,
This is applied to the operation command relay 21.

In this way, when the operation command relay 21 operates, the relay 23 operates, and subsequently the relay 26 also operates. Since this relay 26 operates the electromagnetic contactor 12, the electric motor 1 is finally operated when the main circuit 31 outputs the start command signal. Note that even if the start command signal disappears when the electric motor 1 is operating normally, an operation confirmation signal by closing the contact 26-a is applied to the AND circuit 33 in its place, so the operation command signal still remains. continues to be output.

Next, when the electric motor 1 becomes overloaded, the thermal relay 13 detects this and switches the contact 13-c from the B side to the A side, so the relay 25 operates and the contact 2
The “H” level overload signal due to opening of 5-a
The signal is applied to the NOT input terminal of the AND circuit 33, and as a result, the output of the AND circuit 33 turns OFF, the operation command signal disappears, and the operation command relay 21 returns to its normal state, and at the same time, the electric motor 1 also stops.

In such a conventional general operation control device for an electric motor, since the thermal relay 13 has only one switching contact, a dedicated relay 25 for detecting overload is provided, and the contact of this relay 25 is As a result, an overload signal was obtained. This means that each start control circuit 20 has a relay 25 for detecting overload, and for example, when controlling 200 motors, the configuration becomes complicated and the construction cost is also large. It was something.

The present invention has been made to eliminate the above-mentioned drawbacks, and an object of the present invention is to provide an overall operation control device for an electric motor that can significantly simplify the configuration and reduce construction costs. .

In order to achieve the above object, the overall operation control device for an electric motor of the present invention includes a failure determination circuit that determines that there is a failure in the electric motor when an operation command signal is given and an operation confirmation signal is not present. It is set inside.

Hereinafter, one embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 2 is a circuit diagram partially showing the configuration of the general operation control device for an electric motor according to the present invention in blocks.
The same reference numerals as in FIG. 1 indicate the same elements. And relay 2 in Figure 1
The difference from FIG. 1 is that 5 has been removed and that a failure determination circuit 34 has been newly added to the overall control circuit 30.

This failure determination circuit 34 uses a first signal acquisition means that sequentially acquires operation command signals, a second signal acquisition means that sequentially acquires operation confirmation signals corresponding to the operation command signals, and compares these two signals to generate an operation command. A plurality of activation control circuits 2 each include a determination means for controlling the operation command signal to stop when a corresponding operation confirmation signal is not input when a signal is input.
A start command signal is given by sequentially taking in the operation command signal of the main circuit 31 corresponding to 0, and sequentially taking in the operation confirmation signal accompanying the closing of the contact 26-a, and comparing these signals with each other. However, when there is no operation confirmation signal, it is determined that an overcurrent has flowed to the motor.

The operation of this embodiment will be explained based on FIG. When the electric motor 1 is to be operated in general, the no-fuse breaker 11 is turned on and the mode selection switch 22 is switched to "CENTER" as in the prior art. As a result, no fuse breaker 1
The first auxiliary contact 11-a is closed, and the relay 24 is energized to close the contact 24-a. By closing the contact 24-a, the interlocking condition signal becomes "H" in the overall control circuit 30 and is input to the AND circuit 33. this
The AND circuit receives an “H” activation command signal output from the main circuit 31 through the OR circuit 32, and an “H”
Since the interlock signal, the "L" overload signal, and the "L" stop signal from the main circuit 31 are input to each NOT input terminal of the AND circuit, the logical conditions are satisfied and the operation command is issued. A signal is generated. After this driving command signal is generated, the driving command signal is sent to the AND circuit instead of the start command signal.
It is input through the OR circuit 32. Further, in accordance with this operation command signal, the relay contact 21 in the start control circuit 20 closes to excite the relay 23, and by closing the contact 23-a of the relay 23, the relay 23 enters the closed state. The relay 26 connected in series with the thermal relay contact 13-c is energized. relay 26
When excited, the electromagnetic contactor 12 of the starting circuit 10 closes, the motor 1 is operated, and the contact 26-a in the starting control circuit 20 outputs an operation confirmation signal.
is closed.

Each activation control circuit performs the above operation for each activation circuit 10, causes the general control circuit to output an operation command signal, and outputs an operation confirmation signal in accordance with each operation command signal.

When a plurality of electric motors are collectively operated, the failure determination circuit 34 in the general control circuit 30 sequentially inputs the operation command signal output to each start control circuit and determines whether it is ON or not. Furthermore, a driving confirmation signal corresponding to the driving command signal that is ON is input, and it is determined whether or not the driving command signal is ON.

At this time, when the electric motor 1 is operating according to the operation command signal, the contact 13-c of the thermal relay 13 remains closed and the relay 26 is energized unless there is an overload, so the closing of the contact 26-a causes the operation confirmation signal to be sent. is output to the failure determination circuit 34.

Therefore, if the operation confirmation signal is determined to be OFF while the operation command signal is determined to be ON, contact 26
-a is opened, that is, the motor is overloaded, the thermal relay contact 13-c is opened by the operation of the thermal relay 13, and the relay 26 is demagnetized, so the contact 26-a is opened and the operation confirmation signal is turned OFF.

In this way, if the operation confirmation signal is determined to be OFF, a failure is determined and the overload signal of "H" is output.
Input to the NOT input terminal of AND33. As a result, the general control circuit 30 releases the operation command signal to the activation control circuit that has determined the failure.

As described above, the failure determination circuit 34 sequentially inputs the operation command signal and also inputs the operation confirmation signal output in response to the operation command signal, compares both signals, and outputs an overload signal according to the comparison result. Since the output is made, it is possible to eliminate the need for a relay for failure detection in each startup control circuit.

Therefore, it is clear that exactly the same effect as shown in FIG. 1 is performed, thereby simplifying the configuration of the startup control circuit 20.

Although overload has been described as a failure in the above embodiments, the same operation is performed not only for overload but also for short circuits between power supply lines, electrical or mechanical failures of motors, and the like.

As is clear from the above description, according to the general operation control device for an electric motor of the present invention, the general control circuit includes a first signal receiving means for sequentially taking in operation command signals, and a first signal receiving means for sequentially taking in operation command signals, and The second signal capturing means sequentially captures confirmation signals, and a judgment device that compares these two signals and controls the operation command signal to stop when it is determined that the corresponding operation confirmation signal is not input when the operation command signal is input. By providing a fault detection circuit for one motor or a series of motors, it is possible to eliminate the relay for fault detection in the start control circuit that is provided for one or a series of motors, significantly simplifying the overall configuration of the device, and The greater the number of units, the greater the effect of reducing construction costs.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing the configuration of a conventional comprehensive operation control device for an electric motor, and FIG. 2 is a circuit diagram partially showing the configuration of an embodiment of the general operation control device for an electric motor according to the present invention in blocks. be. 1: Electric motor, 10: Starting circuit, 11: No-fuse breaker, 12: Magnetic contactor, 13: Thermal relay, 20: Starting control circuit, 21: Operation command relay, 22: Mode selection switch, 23-2
6: Relay, 30: General control circuit, 31: Main circuit, 32: OR circuit, 33: AND circuit, 34: Failure determination circuit.

Claims (1)

[Claims] 1. Provided in each power supply circuit of multiple electric motors,
a starting circuit having an electromagnetic contactor that opens and closes a power supply circuit and an overcurrent relay that detects an overcurrent in the power supply circuit; and a starting circuit that sets an operation mode of the electric motor, receives an operation command signal when the mode is determined, and operates the electromagnetic contactor. , a start control circuit corresponding to each motor that resets the electromagnetic contactor when the overcurrent relay operates and outputs an operation confirmation signal when the electromagnetic contactor operates; and a start control circuit corresponding to each motor that outputs an operation command signal when determining the operation mode of the electric motor. a first signal acquisition means that sequentially outputs the operation command signal to the overall control circuit, comprising a general control circuit that sequentially outputs the operation command signal in addition to each of the start control circuits and stops the operation command signal in the event of a motor circuit failure; A second signal capturing means sequentially captures driving confirmation signals corresponding to the driving command signal, and compares these two signals to control the driving command signal to stop when the driving command signal is input and when it is determined that the corresponding driving confirmation signal is not input. 1. A general operation control device for an electric motor, characterized in that a failure determination circuit comprising a determination means is provided in the general control circuit.