JPH03212195A - Motor curtain drive unit - Google Patents

Abstract

PURPOSE:To reduce the size, the weight and the cost by feeding a high frequency rectangular AC voltage intermittently to a high frequency transformer, rectifying and smoothing high frequency output from the high frequency transformer and applying a DC voltage onto a motor, and obtaining a voltage signal corresponding to the curtain speed. CONSTITUTION:An Ac commercial source voltage is rectified and smoothed to produce a DC voltage, which is then switched through a switching element Q1 according to a curtain speed signal to produce a high frequency rectangular intermittent AC voltage. The high frequency rectangular AC voltage is fed to a high frequency transformer T1 and the high frequency output therefrom is then rectified and smoothed thus applying a DC voltage onto a motor M. On the other hand, a voltage signal corresponding to the curtain speed is obtained across a resistor Rs.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an electric curtain drive device that controls opening and closing of curtains using a switch or the like.

[Prior art] When opening and closing curtains at a desired speed using a motor,
The curtain opening/closing speed is affected by curtain weight and power supply voltage fluctuations, so some kind of constant speed control is required.

Conventionally, as shown in Fig. 3, the speed control of a general DC motor has been carried out by converting the commercial power line #AC into the rated DC voltage (2), which is applied to the motor coil by a transformer T2, a diode bridge DB, and a smoothing capacitor C3. Making and detection circuit 10
The speed feedback signal obtained is converted into a constant current source using an operational amplifier, transistor 2, etc.
The voltage applied to the motor coil was controlled. This method directly controls the motor coil current, so
Although it has the advantage of providing high-speed response, commercial power supply A
Since C is isolated and stepped down using the transformer T2, there is a problem that the transformer T2 is large and heavy.

In addition, as another conventional example, when controlling electric curtains by remote control, etc., the input signal of the drive device is generally given as a trigger, and one trigger input starts the curtain, and the curtain is completely opened. Or closed, when the motor is in forced stop state, the motor coil current needs to be cut off.

Conventionally, this type of electric curtain driving device using commercial power supply starts the motor with a single trigger input, and usually takes longer than the maximum time from when the curtain is completely opened or closed until the motor is forced to stop. A timer set for a long time,
Alternatively, a sensor was used to detect the forced stop position and the motor coil current was cut off. However, when using a timer, even though the motor is in a forced stop state,
Since the motor coil current continues to flow until the time set by the timer, the motor and drive unit generate heat, shortening their lifespan and deteriorating efficiency.If a sensor is used, the sensor and its signal processing circuit This poses a problem in that the driving device becomes complicated and expensive.

[Problems to be Solved by the Invention] In the above conventional method, when controlling the curtain opening/closing speed,
The rated DC voltage applied to the motor is obtained from a commercial power supply using a transformer, which has the problem of being large and heavy. When controlling electric curtains with trigger input, the life and efficiency of the motor and drive device are shortened. There have been problems in that the drive device has become expensive and complicated.

The present invention has been provided in view of the above-mentioned points, and is a simple, compact, lightweight, and highly efficient electric curtain drive that can control curtain opening/closing speed by controlling curtain opening/closing speed and by inputting a trigger such as remote control. The purpose is to provide equipment.

[Means for Solving the Problems] The present invention provides a high-frequency transformer whose primary side is connected in parallel to a DC power source obtained by rectifying and smoothing a commercial power source via a switching element, and a secondary side of this high-frequency transformer. a DC smoothing circuit that supplies a DC voltage obtained by rectifying and smoothing a high frequency output from the motor to the motor; a speed detection means that detects the opening/closing speed of the curtain based on the voltage across a resistor inserted between the switching element and the ground; A constant speed control means is constituted by a control circuit that receives a signal from the detection means and controls the switching element on and off in order to keep the opening/closing speed of the curtain constant.

Further, in claim 2, when the curtain reaches the end of the rail, a speed detection means detects that the opening and closing of the curtain has stopped, and an automatic curtain stop circuit is provided that cuts off the power supply being supplied to the motor. It is something.

[Function] Therefore, the DC voltage obtained by rectifying and smoothing the commercial power supply is
A switching element supplies intermittent high-frequency rectangular wave alternating current to a high-frequency transformer according to the curtain speed signal, and the high-frequency output of the high-frequency transformer is rectified and smoothed to apply DC voltage to the motor, thereby reducing the size of the transformer. It is possible.

In addition, a resistor is used to obtain a voltage signal corresponding to the speed of the curtain, thereby reducing costs.

Further, in claim 2, using the speed signal of the curtain,
When the curtain is completely opened or stopped and the motor is forcibly stopped, the power supply to the motor is cut off and the motor coil current is cut off to prevent the motor and the drive device from generating heat. There is.

[Example] Hereinafter, an example of the present invention will be briefly described with reference to the drawings. FIG. 1 shows a circuit diagram of the present invention, in which the switch SW + is for turning on and off the commercial power supply AC, and the operation switch SW2
is a switch for opening and closing the curtains. Commercial power supply AC is input to rectifier D1 via switch SW, and its output is given to capacitor C. A series circuit of a high frequency transformer T1, a transistor Q1, and a resistor Rs is connected to the capacitor C1. 2 of this high frequency transformer T
A DC smoothing circuit including a rectifier D2, a choke coil L1, and a capacitor C2 is connected to the next side, and its output is connected to the motor M via a relay circuit R1.

Both ends of the resistor Rs are input to the PWM control circuit 1, and at the same time are connected to the other input of a comparator 2 whose one input is the reference voltage Vr, and the output of the PWM control circuit 1 is connected to the transistor Q.

is input. The output of the comparator 2 is input to the logic control circuit 3, and together with the input of the operation switch SWz, the determined state is sent from the logic control circuit 3 to the switch SW and the relay circuit R1.

The operation switch SW2, the logic control circuit 3, etc. constitute an opening/closing control means, and the PWM control circuit 1 also includes a speed detection means for detecting the opening/closing speed of the curtain, and a control circuit for controlling the on/off of the transistor Q1. It consists of

The operation will be explained below. The AC input voltage of the commercial power supply AC is rectified by a rectifier, smoothed by a capacitor C to become a DC voltage, and further supplied to a high frequency transformer T1 as a rectangular wave AC interrupted by a transistor Q1. The rectangular wave AC voltage converted into the secondary winding of the high frequency transformer T is rectified by a rectifier D2, smoothed by a choke coil L and a capacitor C2, and output as a DC output voltage Vd, which is used to switch open/close. is supplied to the relay circuit R1. The relay circuit R1 has an H-bridge configuration, is controlled by the logic control circuit 3, and supplies positive and negative DC output voltages to the motor M incorporated in the curtain rail.

A voltage Vs proportional to the speed of the motor M is generated across the resistor Rs, and this voltage controls the PWM control circuit 1 to change the on-duty of the transistor Q.
The speed of the motor M is controlled to control opening and closing of the curtain.

The voltage Vs across the resistor Rs is input to the comparator 2, and as shown in FIGS. 2(a) and 2(b), when the curtain reaches the end of the rail, the current I9 flowing through the motor M increases. , the voltage Vs also increases. When this voltage Vs exceeds the reference voltage Vr set in advance by the comparator 2, the output 1 of the comparator 2 reverses its state (Fig. 2 (C)), and this change causes the logic control circuit 3 to The power switch SW1 is controlled to be turned off (FIG. 2(d)). Note that the logic control circuit 3 is operated by an operation switch SW.
Depending on the state of step 2, the relay circuit R is switched so that the motor M operates in the direction of opening or closing the curtain, and the switch SW1 is turned on. Note that the comparator 1, logic control circuit 3, etc. constitute an automatic curtain stop circuit.

[Effects of the Invention] As described above, the present invention includes a high-frequency transformer whose primary side is connected in parallel to a DC power source obtained by rectifying and smoothing a commercial power source via a switching element, and a two-way transformer of this high-frequency transformer.
a DC smoothing circuit that supplies a DC voltage obtained by rectifying and smoothing the high frequency output from the next side to the motor; and a speed detection means that detects the opening and closing speed of the curtain based on the voltage across the resistor inserted between the switching element and the ground. Since the constant speed control means is configured with a control circuit that receives a signal from the speed detection means and controls the switching element on and off in order to keep the opening and closing speed of the curtain constant, the commercial power source can be rectified and smoothed. The resulting DC voltage is then intermittent high-frequency rectangular wave AC is supplied to a high-frequency transformer using a switching element according to the speed signal of the curtain, and the high-frequency output of the high-frequency transformer is further rectified and smoothed to apply DC voltage to the motor. By doing so, the transformer can be made smaller and the driving device can be made smaller and lighter. Furthermore, since a voltage signal corresponding to the speed of the curtain is obtained by a resistor, the cost can be significantly reduced compared to conventional speed detectors.

Further, in claim 2, when the curtain reaches the end of the rail, a speed detection means detects that the opening and closing of the curtain has stopped, and an automatic curtain stop circuit is provided that cuts off the power supply being supplied to the motor. Since the curtain speed signal is used to detect when the curtain is completely opened or stopped and the motor is forced to stop, the power supplied to the motor is cut off and the motor coil current is cut off. This prevents the motor and drive device from generating heat, resulting in a longer life and higher efficiency.In addition, as there is no need for sensors and their signal processing circuits as in the past, the drive device can be simplified and
This has the effect of making it possible to reduce costs.

[Brief explanation of drawings]

FIG. 1 is a block circuit diagram of an embodiment of the present invention, FIG. 2 is an operational waveform diagram of the same, and FIG. 3 is a circuit diagram of a conventional example. AC is a commercial power supply, T is a high frequency transformer, M is a motor, and Rs is a resistor.

Claims (2)

[Claims] (1) A motor that drives the curtain to open and close and is built into the curtain rail and is forced to stop while the power is applied when the curtain is completely opened or closed. In an electric curtain drive device that is equipped with an opening/closing control means that controls opening, closing, and stopping, and a constant speed control means that detects the opening/closing speed of the curtain and opens and closes the curtain at a constant speed at a set speed, a commercial power supply is provided. A high-frequency transformer whose primary side is connected in parallel to the DC power obtained by rectifying and smoothing the DC power, and a DC voltage obtained by rectifying and smoothing the high frequency output from the secondary side of this high-frequency transformer is supplied to the motor. a DC smoothing circuit that detects the opening and closing speed of the curtain, a speed detection means that detects the opening and closing speed of the curtain based on the voltage across the resistor inserted between the switching element and the ground, and a constant opening and closing speed of the curtain in response to a signal from the speed detection means. With a control circuit that controls on/off the above switching element in order to
An electric curtain drive device comprising the constant speed control means described above. (2) When the curtain reaches the end of the rail, a speed detection means detects that the opening and closing of the curtain has stopped, and is equipped with an automatic curtain stop circuit that cuts off the power supplied to the motor. The electric curtain driving device according to claim 1.