JP3611624B2 - Shutter drive device - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a shutter driving device that prevents a shutter from being opened by an external force when fully closed, and temporarily stops a descent when there is an obstacle.
[0002]
[Prior art]
In general, a shutter drive device is a micro switch that detects a predetermined opening position or a closing position of the shutter by rotating a motor that drives the shutter in a forward or reverse direction under the control of a microcomputer based on commands of an up switch and a down switch. Thus, the driving of the motor is stopped.
[0003]
When the motor is stopped, the power supply to the motor is cut off when the shutter is raised or lowered, and both terminals of the motor are short-circuit grounded to generate strong electromagnetic coupling in the motor. What obtains a large braking force is known. In this braking method, the braking torque increases as the rotational speed of the motor increases, and decreases as the rotational speed decreases.
[0004]
In addition, in the conventional shutter driving device, when there is a person or an obstacle under the shutter when the shutter is lowered in the fully closed direction, the obstacle is automatically detected to avoid danger. It has been proposed that the lowering of the shutter is temporarily stopped, subsequently raised slightly, then lowered again, and when there is still an obstacle, the lowering of the shutter is stopped at that position.
[0005]
[Problems to be solved by the invention]
However, in such a conventional shutter drive device, when the shutter drive motor is rapidly braked using electromagnetic coupling as described above, for example, when the shutter is stopped in a fully closed state, an external force is applied to the shutter. When this is slowly raised, the large braking torque does not act as described above, so that the shutter is gradually opened and finally fully opened, which is not desirable for crime prevention.
[0006]
Moreover, when there is an obstacle at the lower part of the shutter as described above, the shutter is finally stopped at the position where the obstacle is present, which is not preferable for crime prevention. Further, in order to lower the shutter again, there is a problem that a reset operation for starting the motor drive is required.
[0007]
The invention of claim 1 is made to solve the conventional problems as described above. When the shutter is in a state other than the fully closed state, the shutter is forcibly lowered in the fully closed direction by a motor. An object of the present invention is to provide a shutter driving device that can prevent the shutter from being easily opened by applying an external force.
[0008]
According to the second aspect of the present invention, when there is an obstacle when the shutter is lowered, the lowering operation of the shutter is stopped and the shutter is freed so that it can be easily opened and closed by an external force. It is an object of the present invention to obtain a shutter drive device that can automatically control the shutter to descend in the fully closed direction again after being removed.
[0009]
[Means for Solving the Problems]
The shutter driving device according to the first aspect of the present invention includes a motor driver circuit for rotating the shutter driving motor forward or backward, and each relay connected to both terminals of the motor and turned off when the relay operates. A contact, an electromagnetic brake switch that is turned on to ground both terminals of the motor via the relay contact, and applies an electromagnetic brake to the motor; and a lower limit position of the shutter in conjunction with the rotation of the motor The motor driver circuit when the shutter is not in the ascending mode and the electromagnetic brake switch is on and the lower limit position is not detected by the lower limit switch. The motor is driven in the fully closed direction.
[0010]
A shutter driving device according to a second aspect of the present invention includes a motor driver circuit that rotates the shutter driving motor in a forward or reverse direction, a current detection circuit that is connected to the motor driver circuit and detects a current flowing through the motor, Each of the relay contacts connected to both terminals of the motor and turned off when the relay operates, and the motor is turned on so that both terminals of the motor are grounded via the relay contact. An electromagnetic brake switch for applying a brake, and when the current detected by the current detection circuit exceeds a set value, the microcomputer stops the lowering drive of the motor by the motor driver circuit, and After the set time has been released by the operation, the lowering drive of the motor is resumed. .
[0011]
[Action]
In the shutter driving device according to the first aspect of the present invention, the shutter is opened by an external force when the shutter is driven by a motor in the fully closing direction and the motor is stopped by applying an electromagnetic brake to the motor by short-circuit grounding of both terminals of the motor. In order to prevent the possibility of being possible, when the operation of the shutter is not in the ascending mode and is in the electromagnetic brake mode, if the lower limit switch stops detecting the lower limit position of the shutter due to external force application, etc. The motor is driven in the fully closed direction of the shutter.
[0012]
According to a second aspect of the present invention, in the shutter driving device, when the lowering of the shutter is blocked by an obstacle, the increase in the load current of the motor accompanying the lowering of the shutter is detected by the current detection circuit. When the motor exceeds the set value, the motor driver circuit stops the lowering drive of the motor, and the electromagnetic brake is released for a certain short time, so that the obstacle can be removed during this time, and automatically after the obstacle is removed A motor is driven to drive the shutter down.
[0013]
【Example】
An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a circuit diagram showing a shutter driving device according to the present invention. In FIG. 1, 1 is a power transformer connected to an AC power source, and 2 is a bridge-connected rectifier connected to the power transformer 1.
[0014]
3 is a microcomputer connected to the rectifier 2 via the constant voltage circuit 4, 5 and 6 are smoothing capacitors, and 7 is connected between the rectifier 2 and the output terminal A of the microcomputer 3 via the inverter 8. The relay is turned on during motor rotation described later. Reference numeral 9 denotes a diode as a noise canceller connected in parallel to the relay 7.
[0015]
Further, 10 and 11 are PNP transistors and NPN transistors connected in series to the power source, and 12 and 13 are PNP transistors and NPN transistors also connected in series to the power source. These transistors 10 and 12 are protected. Diodes 14 and 16 are connected in parallel, and protective diodes 15 and 17 are grounded between the collectors of the transistors 11 and 13 and the ground.
[0016]
Reference numerals 18, 19, 20, and 21 denote bias resistors inserted between the base and emitter of the transistors 10 to 13, and reference numerals 22, 23, 24, and 25 denote base resistors. These are the transistors 10 to 13 and the diode 14 described above. The motor driver circuit 26 is configured together with .about.17, and those formed as one IC element can be used if necessary.
[0017]
The output terminal B of the microcomputer 3 is connected to the base of the PNP transistor 10 through the base resistor 22 and is connected to the base of the NPN transistor 13 through the inverter 27 and the base resistor 25.
[0018]
On the other hand, the output terminal C of the microcomputer 3 is connected to the base of the NPN transistor 11 through the inverter 28 and the base resistor 23, and is connected to the base of the PNP transistor 12 through the base resistor 24.
[0019]
A motor 29 for driving the shutter has both terminals connected to the connection point of the transistors 10 and 11 and the connection point of the transistors 12 and 13, and a noise absorbing capacitor 30 is connected in parallel to the motor 29. It is connected.
[0020]
7a and 7b are relay contacts of the relay 7 connected to both terminals of the motor 29, which are connected to each other via backflow prevention diodes 31 and 32, and further an electromagnetic brake switch provided in the operation switch section 33. 34 is grounded.
[0021]
Reference numeral 35 denotes a lower limit switch that opens and closes according to the rotation of the motor 29. The movable contact piece 35a is connected to a power source via a contact 35b that is grounded when closed and a pull-up resistor 36 when opened. The movable contact piece 35 a is connected to the input terminal D of the microcomputer 3.
[0022]
Further, 37 is a current detection resistor connected between the emitters of the transistors 11 and 13 and the ground, 38 is a bypass capacitor for removing motor noise, and these connection points serve as a comparator via a resistor 39. Connected to the positive input terminal of the operational amplifier 40.
[0023]
The negative input terminal of the operational amplifier 40 is connected to a power source and an operating point adjusting resistor 41, while the output terminal is connected to the input terminal E of the microcomputer 3. Here, reference numeral 42 denotes a resistor for connecting the input / output terminals of the operational amplifier 40 and preventing and stabilizing the chattering phenomenon of the operational amplifier 40.
[0024]
Reference numeral 54 denotes a current detection circuit including the resistors 37, 39, 41, 42, the capacitor 38, and the operational amplifier 40.
[0025]
In the above circuit, 43 to 49, 58 and 59 are pull-up resistors for holding the potential of each circuit at the power supply voltage, and 50 is composed of capacitors 51 and 52 and a crystal resonator 53, which are necessary for operation of the microcomputer 3. A clock oscillation circuit for generating a clock.
[0026]
Further, 55 is a shutter up switch, 56 is a stop switch, and 57 is a down switch, and these are connected between each input terminal F, G, H of the microcomputer 3 and the ground.
[0027]
Next, the operation will be described. First, the AC voltage supplied via the power transformer 1 is rectified by the rectifier 2. The rectified voltage of, for example, DC 5 volts is supplied as a control power source for the microcomputer 3 and the motor driver circuit 26. Further, 24 VDC is supplied to the motor 29 through the motor driver circuit 26.
[0028]
In this state, when the motor 29 is stopped, the output terminals B and C of the microcomputer 3 are both at a high level. When the rising switch 55 is turned on, the input terminal F is at the ground potential. The microcomputer 3 holds a high level signal at the output terminal B and outputs a low level signal to the output terminal C.
[0029]
For this reason, the transistors 11 and 12 are turned on, and the transistors 10 and 13 are kept off. A current flows to the motor 29 through each of these transistors 10 and 12, and the motor 29 rotates forward to raise the shutter, and a micro switch (not shown) is operated at the upper limit (full open) position of the shutter, or the motor current increases. Is detected and stopped at the fully closed position.
[0030]
Therefore, under the control of the microcomputer 3, high level output signals are output from the output terminals B and C, respectively, and the forward drive of the motor 29 is stopped.
[0031]
On the other hand, when the down switch 57 is turned on, the microcomputer 3 outputs a low level signal to the output terminal B and holds and outputs a high level signal to the output terminal C.
[0032]
Therefore, this time, the transistors 10 and 13 are turned on, the transistors 11 and 12 are turned off, and current flows through the motor 29 through the two transistors 10 and 13 in the opposite direction. Reverses and lowers the shutter.
[0033]
During each rotation of the motor 29, the relay 7 is energized, the contacts 7a and 7b are off, and the relays 7 are on otherwise.
[0034]
Therefore, when the electromagnetic brake switch 34 is turned on, as described above, when the motor 29 is reversed in the direction to close the shutter and the shutter is stopped at the lower limit position, according to the rotation of the motor 29, The movable contact piece 35a of the lower limit switch 35 also moves from the contact point 35c and contacts the contact point 35b.
[0035]
Therefore, the movable contact piece 35 a is grounded, and this potential change is input to the input terminal D of the microcomputer 3, and a high level signal is output to both output terminals B.
[0036]
As a result, all the transistors 10 to 13 are turned off, the current supply to the motor 29 is stopped, and the microcomputer 3 outputs a low level signal to the output terminal A to turn off the relay 7.
[0037]
In this case, depending on the polarity of the electromotive force generated when starting the motor 29, the motor 29 → the relay contact 7a → the backflow prevention diode 31 → the electromagnetic brake switch 34 → the ground → the protection diode 17 → the closed loop of the motor 29, or the motor 29 → Relay contact 7b → Backflow prevention diode 32 → Electromagnetic brake switch 34 → Grounding → Protection diode 15 → A current flows in a closed loop of the motor 29 to generate a large power generation braking force.
[0038]
At the same time, when the relay 7 is turned off, both the relay contacts 7a and 7b are closed, and both terminals of the motor 3 are short-circuited via the relay contacts 7a and 7b and the backflow prevention diodes 31 and 32. The point is grounded via the electromagnetic brake switch 34.
[0039]
Therefore, a large electromagnetic coupling action is applied to the motor 29 and sudden braking is applied. In this state, the shutter is held so as not to be opened by an external force.
[0040]
Conventionally, the shutter may be opened by applying the external force slowly but not rapidly. However, the lift switch 55 is not turned on, that is, the shutter is not in the lift mode, and the electromagnetic brake switch 34 is turned on. In some cases, when the shutter is pushed open by the external force, the movable contact piece 35a of the lower limit switch 35 is separated from the contact 35b.
[0041]
For this reason, the ground potential of the output terminal D of the microcomputer 3 is released, and a low level signal is output to the output terminal B again to drive the motor 29 in the reverse direction.
[0042]
As a result, a force in the fully closed direction acts on the shutter, the shutter is held in the fully closed state, and the shutter can be reliably prevented from being opened by an external force.
[0043]
On the other hand, when the motor 29 is driven in the fully closing direction of the shutter, if there is an obstacle under the shutter, the lower end of the shutter comes into contact with the obstacle, and the shutter is lowered. Of great resistance.
[0044]
For this reason, a large braking torque acts on the motor 29, and the load current flowing through the motor 29 increases. Accordingly, the resistor 37 detects the load current, and when the load current increases beyond the set value, the operational amplifier 40 as a comparator inputs a signal to the input terminal E of the microcomputer 3.
[0045]
For this reason, the microcomputer 3 outputs a high level signal from the output terminal B, stops the motor 29, outputs a high level signal from the output terminal A, and activates the relay 7, The contacts 7a and 7b are turned off for a short time such as 1 second.
[0046]
By doing so, the electromagnetic brake of the motor 29 is released during this time, and the shutter is not subjected to any restraining force and is in a free state. Therefore, the shutter can be easily lifted by hand, and the obstacle And people can be removed with peace of mind.
[0047]
In addition, when the short time has passed and the obstacle has been removed, the motor 29 again operates to lower the shutter. However, if the obstacle still remains, the motor 29 again. Since the load current flowing through the motor increases and the motor 29 is stopped and the shutter free state is formed again based on the comparator output, the obstacle can be removed stably and reliably.
[0048]
After the obstacle is removed, the shutter is lowered again in the fully closed direction by driving the motor 29. In the above description, the shutter may be automatically raised to the fully open position following the shutter lowering stop operation.
[0049]
【The invention's effect】
As described above, according to the first aspect of the present invention, when the shutter is not in the ascending mode, the electromagnetic brake switch is in the on state, and the lower limit switch is other than when the lower limit position is detected, the motor is driven through the motor driver circuit by the microcomputer. Since the shutter is driven in the fully closed direction, when the shutter is in a state other than fully closed, the shutter is forcibly lowered by the motor in the fully closed direction to ensure that the shutter can be easily opened by external force. There is an effect of obtaining what can be prevented.
[0050]
According to the second aspect of the present invention, the microcomputer detects that the current detected by the current detection circuit exceeds the set value, stops the motor descending drive by the motor driver circuit, and operates the relay. After releasing the electromagnetic brake for a set time, the motor descent drive is resumed. Therefore, if there is an obstacle when the shutter is lowered, the descent operation of the shutter is stopped and the shutter is opened and closed. After the obstacle is removed and the obstacle is removed, there is an effect that the shutter can be automatically and surely lowered and controlled to be fully closed.
[Brief description of the drawings]
FIG. 1 is a circuit diagram showing a shutter driving device according to an embodiment of the present invention.
[Explanation of symbols]
3 Microcomputer 7 Relay 7a, 7b Relay contact 26 Motor driver circuit 29 Motor 34 Electromagnetic brake switch 35 Lower limit switch 54 Current detection circuit

Claims (2)

A motor driver circuit that rotates the shutter driving motor forward or backward, a relay that is energized and operated while the motor is rotating, and a motor that is connected to both terminals of the motor and that is turned off when the relay operates. Relay contacts, an electromagnetic brake switch that is turned on to ground both terminals of the motor via the relay contacts, and applies an electromagnetic brake to the motor, and in conjunction with the rotation of the motor, When the lower limit switch for detecting the lower limit position and the shutter are not in the ascending mode and the electromagnetic brake switch is on and the lower limit position is not detected by the lower limit switch, all the motors are passed through the motor driver circuit. A shutter driving device including a microcomputer that drives in a closing direction. A current detection circuit connected to the motor driver circuit to detect a current flowing through the motor ; and the microcomputer detects that the current detected by the current detection circuit exceeds a set value, and the motor driver circuit 2. The shutter driving device according to claim 1 , wherein the lowering driving of the motor is stopped and the lowering driving of the motor is resumed after the electromagnetic brake is released for a set time by the operation of the relay.

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