JP2001012175A - Safety device for electric shutter for architecture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a safety device for an electric shutter for architecture adopting a capacitor start type induction electric motor capable of increasing safety by using a simple off-delay timer even when abrupt reverse rotation operation is done. SOLUTION: A motor brake circuit regulating rotation operation of an electric motor M is provided in an electric control circuit X of the electric motor M, and a time constant circuit OFD is provided in the other main circuit Y. When the electric control circuit X is in a closed condition, the time constant circuit OFD is in a charging condition. During the predetermined time constant in the charging condition of the time constant circuit OFD after 3 condition of the electric control circuit X is changed from the closed condition to an open condition, opening and closing operation by an opening and closing means of a shutter curtain is inhibitted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety device for an electric shutter for architectural use using a single-phase motor, and more particularly to a safety device in a case where the opening and closing of a shutter curtain is suddenly reversed by a push button switch or the like as a shutter curtain opening / closing means. It concerns the device.

[0002]

2. Description of the Related Art Three-phase electric shutters are used for electric shutters for construction.
Generally, a three-phase induction motor using an AC power supply of 0 V (volt) is used. However, where there is no such wiring, a single-phase induction motor using a single-phase AC voltage (100 V, 200 V, etc.) as a normal household power supply as a power supply is used. However, unlike a three-phase induction motor, a single-phase induction motor such as a capacitor-start-type motor described below does not make it clear simply by connecting a power supply to which motor to rotate. Therefore, in order to control the forward and reverse rotation directions, the power control circuit is provided with a phase-advancing capacitor that is always energized to advance the AC power supply, and controls the rotation direction of the motor by the phase-advancing action of the phase-advancing capacitor. Many adopt a phase-advancing capacitor method.

[0003] A starting capacitor is wired in series with the starting winding for starting the motor, and the motor is started while controlling the rotation direction of the motor by the phase-advancing action of the starting capacitor. When the rotating state is reached, the starting switch such as a centrifugal switch is turned off to cut off the power supply to the starting winding, so that AC power is applied to the starting capacitor only at the time of starting. Single-phase induction motors were employed. After the motor of this type is in a stable rotation state, it basically continues to rotate in the same direction depending on the rotational inertia of the rotor. However, in this type of motor, when the motor is rotating in a certain direction, even if you try to reverse the rotation by operating the switch on the side that suddenly reverses the rotation, the starting switch is There is no switching to ON, no starting current is applied to the starting winding circuit, and the motor continues to rotate in one direction.

In order to solve the above problem, FIG. 6 is an electric control circuit diagram showing an embodiment of the prior art disclosed in Japanese Patent Application Laid-Open No. 5-149071. Electric motors, MCUs and MCDs are ascending and descending relay switches and their contact switches, PBU, PB
S and PBD are push button switches for ascending, stopping and descending, LSU and LSD are upper and lower limit switches, EMS is an emergency switch, B is a brake device, and L is a starting winding (not shown). , C is a starting capacitor connected in series to the starting winding L, and SS is a centrifugal switch that is turned off when the electric motor M shifts to the rated rotation. The wiring of these member devices is no different from the conventional one. In such an electric control circuit, a rising delay timer switch (coil) TU is provided in parallel with the rising relay switch MCU, and a falling delay timer switch (coil) is provided in parallel with the falling relay switch MCD.
TD is connected, but the rising delay timer switch T
The switch contact TU of U is connected in series with the descending relay switch MCD, and the switch contact TD of the descending delay timer switch TD is connected in series with the ascending relay switch MCU. Here, the rising delay timer switch TU and the falling delay timer switch TD are turned on when the power supply E is turned on.
(Excitation), and both switch contacts TU and TD are turned on. The relationship between the ascending delay timer switch TU and its switch contact TU (or the descending delay timer switch TD and its switch contact TD) is such that the ascending delay timer switch TU (or the descending delay timer switch TD) is When the switch is turned ON, the switch contact TU (or switch contact TD) is also turned OFF.
F, even if the ascending delay timer switch TU (or the descending delay timer switch TD) is turned off, the switch contact TU (or the switch contact TD) is immediately turned on.
Does not return to ON, the OFF state is maintained for a preset timer time, and O
An off-delay timer method set to N (that is, the contact returns) is adopted. However, this timer time is arbitrarily set as necessary,
The energization of each relay switch MCU, MCD is cut off, and the electric motor M is stopped by the operation of the brake device B,
Alternatively, at least a period of time from when the electric motor M is decelerated to when the centrifugal switch SS is turned on is required.

In such a circuit configuration, when it is desired to lower a shutter curtain (not shown), the lowering push button switch PBD is pressed to be turned on, and the lower limit switch LSD in the lowering circuit D, Relay switch MCD, switch contact T
U, the lowering push button switch PBD, the lowering push button switch PBS, and the ヱ martensi switch EMS conduct, the lowering relay switch contact MCD turns ON,
The lowering circuit D is held by itself and the electric motor M
And the electric motor M is rotated to lower the shutter curtain. When the shutter curtain descends and reaches the lower limit, the lower limit switch LSD is turned off, and the lowering circuit D becomes an open circuit, and the switch contact MC of the lowering relay switch is opened.
D switches to OFF and the electric motor M stops. On the other hand, when it is desired to raise the shutter curtain, the raising circuit U becomes a closed circuit by pressing the raising push button switch PBU. Therefore, if the stop push button switch PBS is pressed during the lowering operation of the shutter curtain, the power supply to the lowering delay timer switch TD is also cut off. However, the switch contact TD is set to be kept in the OFF state until a predetermined timer time has elapsed. Therefore, even if the ascending push-button switch PBU is quickly pressed simultaneously (immediately after the stop push-button switch PBS is pushed) at the same time that the descending circuit D becomes an open circuit, The circuit U does not become a closed circuit.

[0006]

According to such a circuit configuration based on the prior art, there is an effect that the problem that the motor continues to be driven in the same direction as it is when the switch is quickly pressed can be reliably avoided. . However, such a circuit configuration requires off-delay timers for ascending and descending, respectively, so that the cost is relatively high. Furthermore, a new defect that a circuit (especially wiring) becomes complicated has arisen.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in order to provide a safety device for an electric shutter which can eliminate the above-mentioned disadvantages.
An electric switchgear for raising and lowering the shutter curtain is provided with a starting coil, a starting capacitor, and a starting switch which is turned off when the motor rotation speed reaches a predetermined rotation speed. In a building electric shutter employing an electric motor, an electric control circuit of the electric motor is provided with a time constant circuit in a motor brake circuit and other main circuits that regulate the rotation of the electric motor, and the electric control circuit is In the closed state, the time constant circuit is charged, and during a predetermined time constant in the discharge state of the time constant circuit after the electric control circuit shifts from the closed state to the open state, the shutter curtain opening / closing means It is characterized in that the opening / closing operation by the device is prohibited. According to the present invention, a single off-delay timer circuit can cope with a sudden reversal operation, even though the electric shutter employs a capacitor-start-type induction electric motor. can do.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In FIG. 1, in which the same reference numerals are used for the same parts as in FIG. 6, X in FIG.
An electric control circuit is defined, and Y in a broken line portion in the figure is defined as a main circuit in the electric control circuit X of the electric motor M. OF
D is a time constant circuit (hereinafter referred to as an off-delay timer circuit).
It is called a time constant circuit. ), Which are provided in parallel with the motor brake circuit. The interlock relay contact RIL corresponding to the interlock relay coil RIL of the time constant circuit is connected to the R-phase side power supply line by the emergency switch EM.
S is connected in series. The interlock relay contact RIL corresponding to the interlock relay coil RIL of the time constant circuit is handled as not included in the time constant circuit for the present invention.

FIG. 2A shows a time constant circuit OFD, in which RY is a relay coil and a relay contact, R is a resistor,
D1 is a rectifying diode, C is a capacitor, and together with the resistor R, forms an integrating circuit of a time constant. D2 indicates a diode for absorbing surge, and RIL indicates an interlock relay coil and its interlock relay contact (normally closed contact). The time constant for operating and returning the interlock relay coil RIL or the interlock relay contact RIL when the capacitor C is discharged will be described later. A part of the circuit may have a DC relay circuit configuration as shown in FIG. 2 (b).

Next, the operation will be described. The operation other than the sudden reversal up / down movement of the shutter curtain by the push operation of the push button switch is the same as that of the above-mentioned known technology, and here, the shutter curtain reaches the floor surface,
As a result of the operation of the lower limit switch LSD, the lowering circuit D becomes an open circuit, and at the same time, the ascending push button switch PBU is pressed and operated, that is, one of the shutter curtain opening / closing means. The state in which the push button switch is quickly pressed will be described with reference to the time constant circuit OFD of FIGS. 3 and 4 and a time chart of FIG. When the electric control circuit X is a closed circuit and the motor brake circuit forming the descending circuit D and the main circuit Y is a closed circuit, the terminals B and B are in an energized state (ON at BB in FIG. 5). Status). In this state, the exciting current flows through the relay coil RY as shown in FIG. 3, so that the relay contact RY also operates in the direction of the arrow, from the live B terminal via the resistor R, the rectifying diode D1, the relay contact RY, and the capacitor C. Power is supplied to the neutral side B terminal. As a result, the capacitor C is charged. However, when the descending circuit D is opened (when BB in FIG. 5 shifts from ON to OFF), the excitation of the relay coil RY is released, and the relay contact RY also returns. As a result, a closed circuit is formed between the capacitor C, the relay contact RY, and the interlock relay coil RIL, an exciting current flows through the interlock relay coil RIL due to the discharging action of the capacitor C, and the interlock relay contact RIL is turned off. Time t during which the interlock relay contact RIL maintains the OFF state
Is the product of the resistance value of the interlock relay contact RIL and the capacitance value of the capacitor C.
Until the voltage between both ends reaches the return voltage of the interlock relay coil RIL, but at least the time until the electric motor M is completely stopped is set to a time constant (within 1 second or outside) which is set in advance. It has been set. Therefore, even if the raising push button switch PBU is simultaneously pressed within this time t, the opening operation of the shutter curtain is prohibited. Originally, the ascending circuit U became an open circuit (for example, the shutter curtain completed a prescribed ascent, and the ascending limit switch LSU
Is activated) and the push button switch PBD for lowering is simultaneously pressed simultaneously.
It is also prohibited.

Although the present invention is mainly applied to a single-phase capacitor-starting induction motor, it can be applied to an electric shutter for construction using a three-phase 200 V (volt) AC power supply. is there.
That is, described in Japanese Patent Publication No. 4-37234 (Fig. 5).
If the time constant circuit OFD of the present invention is used as the main circuit of the electric control circuit of the three-phase motor, it is expected that vibrations to the building structure due to the sudden reversal operation of the heavy shutter can be reduced. it can.

The shutter curtain opening / closing means in the present invention includes, in addition to the push button switch, a remote control switch for opening and closing the shutter curtain by remote control operation, and a remote opening / closing signal from a security system or the like.

[Brief description of the drawings]

FIG. 1 is an electric control circuit diagram of the present invention.

FIG. 2A is a circuit diagram of a time constant. FIG. 3B is a circuit diagram of another time constant.

FIG. 3 shows a state of charge of a capacitor of the time constant circuit.

FIG. 4 shows a discharge state of a capacitor of a time constant circuit.

FIG. 5 shows a time chart of a time constant circuit.

FIG. 6 is a conventional example.

[Explanation of symbols]

B Brake device C Starting capacitor D Falling circuit D1 Rectifying diode D2 Surge absorbing diode E Power supply L Starting winding LSU Upper limit switch LSD Lowering limit switch M Electric motor MCU Upward relay switch and its switch contact MCD Descending relay switch and its switch contact OFD time constant circuit PBU Ascending pushbutton switch PBD Descending pushbutton switch PBS Stopping pushbutton switch RIL Interlock relay coil and its switch contact RY Relay coil and its switch contact SS Starting centrifuge Switch U Ascending circuit X Electric control circuit Y Main circuit

Claims (1)

[Claims] An electric switchgear for raising and lowering a shutter curtain is provided with a starting winding, a starting capacitor, and a starting switch that is turned off when the motor rotation speed reaches a predetermined rotation speed. In a building electric shutter employing a capacitor-starting induction electric motor, an electric control circuit of the electric motor is provided with a time constant circuit in a motor brake circuit and other main circuits that regulate the rotation of the electric motor, In the closed state of the electric control circuit, the time constant circuit is in a charged state, and during a predetermined time constant in the discharged state of the time constant circuit after the electric control circuit shifts from the closed state to the open state, An opening / closing operation of a shutter curtain by an opening / closing means is prohibited.