JP2544712Y2 - Electric shutter control circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a control circuit for an electric shutter.

[Prior Art] Generally, a motor with a drive rating of about 10 minutes is used as an opening / closing motor for an electric shutter, and when driven continuously, or when opening and closing are frequently performed in a short time. In this case, the open / close motor is overheated. Therefore, in the conventional control circuit, a thermal protector is provided, and when the temperature of the opening / closing motor exceeds a predetermined temperature, the power supply to the opening / closing motor is cut off to prevent the opening / closing motor from burning.

 A conventional control circuit will be described with reference to FIG.

In the figure, 1 is a three-phase AC shutter opening / closing motor, 2 is an electromagnetic brake, 3 is a shutter opening relay, 4 is a shutter closing relay, 5 is an opening push button switch, 6 is a closing push button switch, and 7 is a closing push button switch. A stop button switch, 8 is a thermal protector, 9 is an upper limit switch, 10 is a lower limit switch, and 11 is an auxiliary limit switch.

The connection terminal V of the motor 1 is connected to the power supply terminal S, and the connection terminals U and W of the motor 1 are connected to the power supply terminals R and T when the open contacts 3a and 3b of the relay 3 are closed. When the motor 1 is driven in the direction to open the shutter, the connection terminals U and W of the motor 1 are connected to the power supply side terminals T and R when the open contacts 4a and 4b of the relay 4 are closed to close the shutter. The motor 1 is driven in the direction. The electromagnetic brake 2 is provided so as to restrain the motor 1 when the power is not supplied (when the motor 1 is not driven) and release the motor 1 when the power is supplied.

A thermal protector 8 and a stop push button switch 7 are connected to the T terminal on the power supply side, and the push button switch 7 is further connected to the release push button switch 5 via the closing contact 4C of the relay 4. The relay 3 and the upper limit switch 9 are connected in sequence, the open line 12 is connected, the closing push button switch 6, the relay 4 and the lower limit switch 10 are sequentially connected to the closing push button switch 6 via the closing contact 3C of the relay 3. The upper limit switch 9 and the lower limit switch 10 are connected to the S terminal on the power supply side via the auxiliary limit switch 11.

The closed contact 4c of the relay 4 is connected to the stop push button switch 7 via the open contact 3d of the relay 3, and the closed contact 3c of the relay 3 is connected to the stop push button switch 7 via the open contact 4d of the relay 4. Have been.

For example, when the release push button switch 5 is pressed in the above circuit, the relay 3 is energized and excited, the contacts 3a and 3b are closed, and the contact 3c
Is opened, the brake 2 is released, and the motor 1 is energized to drive in the release direction. At this time, the excitation state of the relay 3 is maintained by closing the contact 3d, and the driving of the motor 1 is continued even when the release push button switch 5 is released.

The driving of the motor 1 is stopped by operating the stop push button switch 7 or by opening the shutter to the upper limit and operating the upper limit switch 9.

Next, when the closing push button switch 6 is pressed, the relay 4 is energized and excited, the contacts 4a and 4b are closed, and the contact 4c is opened. The relay 4 is self-holding and a stop push button switch 7
Is operated or the lower limit switch 10 is operated to drive the motor 1.

The contacts 3c and 4c prevent the power supply line of the motor 1 from short-circuiting when the closing push button switch 6 is erroneously operated during the opening operation and the opening push button switch 5 is erroneously operated during the closing operation. The auxiliary limit switch 11 is a safety switch for when the shutter overruns.

[Problem to be Solved by the Invention] In the conventional control circuit described above, when the motor 1 is overloaded and overheated and the thermal protector 8 is activated, the power supply lines to the relays 3 and 4 are cut off. ,relay
3, 4 are de-energized, and contacts 3a, 3b, 4a, 4b in any state
Is opened, and the motor 1 stops.

Since the thermal protector 8 operates until the motor 1 is sufficiently cooled, the state in which the motor 1 cannot be driven continues for a long time of several tens of minutes.

Therefore, during that time, the shutter is left open halfway or closed. For this reason, if the location where the shutter is provided is the entrance of the basement parking lot of the apartment, the entrance of the factory, the warehouse, it will not be possible for cars to enter or exit, was there.

The present invention has been made in view of the above circumstances, and aims to solve the problem caused by the operation of the thermal protector by opening the shutter at least to the upper limit even when the thermal protector operates.

[Means for Solving the Problems] In the present invention, the operation of the opening / closing relay is energized by operating the opening / closing push button switch, the opening / closing relay is operated, and the operation of the opening / closing relay supplies power to the opening / closing motor. In a control circuit of an electric shutter configured to cut off a connection between the open / close push button switch and a power supply by an operation of the protector, the thermal protector and the open / close relay and a power supply connected in series to the thermal protector are connected to each other. Another relay to be disconnected is connected to a power supply in parallel with the switching relay, and a timer started through the other relay by the operation of the thermal protector and connected in series to the timer. And a limit switch for detecting the operation limit of the shutter, the thermal protector,
Connected to a power supply so as to be in parallel with the another relay, and connected to a power supply and the open / close relay in parallel with the open / close push button switch, and a contact that is closed after a lapse of a predetermined time from the activation of the timer; The switching relay is configured to be energized through the contact.

[Operation] When the thermal protector operates due to overheating of the motor, the push button switch and the power supply are shut off, so that the opening and closing operation by the push button switch becomes impossible. Next, by directly energizing the relay after a lapse of a predetermined time, the shutter opens or closes until the shutter operates the limit switch irrespective of the operation of the push button switch.

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

In this embodiment, the above-mentioned conventional control circuit is improved. In FIG. 1 and FIG. 3, the same components as those shown in FIG. Will be described.

A thermal protector 8 and a first relay 15 are connected in series to the connection terminals S and R on the power supply side, and a second relay 17 and an upper limit switch 9 are connected in parallel to the thermal protector 8 and the first relay 15. , And for the second relay 17,
A timer 16 having a set time of about 0.5 seconds until an electric signal is generated after startup and a closed contact 15b of the first relay 15 are connected in parallel. The timer 16 is a relay-integrated timer with a built-in relay.
Is closed.

An open contact 15a of the first relay 15 is provided at the position of the thermal protector 8 of the conventional control circuit, and an open contact 17a of the second relay 17 is provided at the position of the upper limit switch 9. Further, the closing contact 4c of the shutter closing relay 4 is connected to the terminal T via the opening contact 16a of the timer 16.

In such a configuration, in the steady state, the first relay 15 is energized, the closed contact 15b is open, the timer 16 is not operated, and the open contact 15a is closed. Further, when the shutter is not opened to the upper limit, the upper limit switch 9 is closed and the second relay 17 is excited. Therefore, the open contact 17a is closed, and the shutter can be opened or closed by operating the opening push button switch 5 or the closing push button switch 6, as in the conventional control circuit described above.

Further, when the shutter is fully opened and the upper limit switch 9 is operated, the second relay 17 is de-energized, the open contact 17a is opened, the shutter open relay 3 is de-energized, and power supply to the motor 1 is cut off. , The motor 1 stops.

Next, when the thermal protector 8 operates while the motor 1 is overheated and the shutter is not fully opened, the first relay
15 is de-energized and the open contact 15a is opened, so that neither the shutter opening relay 3 nor the shutter closing relay 4 is energized, and the power supply to the motor 1 is stopped. Due to the non-excitation of the first relay 15, the closed contact 15b is closed, and the energization of the timer 16 is started. The timer 16 is started by the operation of the thermal protector 8 and closes the self-opening contact 16a after a set time (for example, 0.5 seconds), and the shutter release relay 3 is not pushed through the push buttons 5, 6, and 7 without passing through the push buttons 5, 6, and 7. Ensure that power is supplied directly.

Thus, the motor 1 is driven in the opening direction, and the shutter is opened until the upper limit switch 9 operates.

That is, even if the thermal protector 8 operates, the shutter always stops at the fully opened state without stopping during the closing or opening. The operating point of the thermal protector 8 is the motor 1
In order to protect the motor 1, the motor 1 is not burned by the operation of opening the shutter after the operation of the thermal protector.

 Next, another embodiment will be described with reference to FIG.

In the above-described embodiment, the shutter is opened when the thermal protector operates. However, when the thermal protector operates at night, the shutter may be closed to lock the door.

In this case, similar to the opening auxiliary circuit 21 constituted by the first relay 15, the timer 16, the second relay 17 and the like, the third
A closing auxiliary circuit 22 composed of a relay 18, a fourth relay 19, a thermal protector 8 ', a lower limit switch 10 and the like is provided in parallel with the opening auxiliary circuit 21.
The connection between the power supply and the power supply is connected to the contacts 20a and 20 of the timer (not shown).
Switching is performed by b, so that the opening auxiliary circuit 21 is connected during the day and the closing auxiliary circuit 22 is connected at night.

The operation of the closing auxiliary circuit 22 is the same as that of the opening auxiliary circuit 21, and when the thermal protector 8 operates, the timer 16 '
Contact 16a 'is closed, and the shutter closing relay 4
Is supplied directly to the motor 1 until the shutter operates the lower limit switch 10.

Note that a remote switch that is switched by remote control may be used instead of the timer.

[Effects of the Invention] As described above, according to the present invention, even when the thermal protector provided for protecting the motor operates, the shutter does not stop halfway, so that the shutter is not halfway. It has an excellent effect of eliminating various inconveniences that occur when stopping.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing one embodiment of the present invention, FIG. 2 is a circuit diagram showing another embodiment, and FIG. 3 is a circuit diagram of a conventional example. 1 is a motor, 3 is a shutter opening relay, 4 is a shutter closing relay, 5 is an opening push button switch, 6 is a closing push button switch, 7 is a stop push button switch, 9 is an upper limit switch, and 10 is a lower limit switch. , 16 indicate a timer.

Claims (1)

(57) [Scope of request for utility model registration] An opening / closing relay is energized by operating the opening / closing pushbutton switch, the opening / closing relay is operated, power is supplied to the opening / closing motor by the operation of the opening / closing relay, and the opening / closing pushbutton is operated by operation of the thermal protector. In a control circuit of an electric shutter configured to cut off a connection between a switch and a power supply, the thermal protector and another relay connected in series with the thermal protector and disconnecting the open / close relay and the power supply are connected to each other. A timer which is connected to a power supply in parallel with the opening / closing relay and which is started via the other relay by the operation of the thermal protector, and which is connected in series with the timer to detect an operation limit of a shutter. A limit switch, the thermal protector,
Connected to a power supply so as to be in parallel with the another relay, and connected to a power supply and the open / close relay in parallel with the open / close push button switch; A control circuit for an electric shutter, wherein the switching relay is energized through the contact.