CN2469835Y - Motor drive for electric curtains - Google Patents

Abstract

A motor drive device for an electric curtain comprises a driving circuit for driving a motor, a controller for controlling the motor to stop and rotate forward and reverse, a current limiting circuit for controlling the current flowing into the driving circuit, and an overload detection circuit for detecting the output current of the current limiting circuit and sending a control signal to the controller in a timely manner to stop the motor, and controlling the opening and closing of the electric curtain motor in a timely manner, thereby controlling the switching action of the curtain fabric, so as to prevent the motor from burning out due to overload.

Description

Motor drive for electric curtains

The utility model relates to a motor drive device, in particular to a motor drive device for the electric curtain which can effectively control the motor operation of the electric curtain so as to protect the motor timely so as not to be burnt due to overload.

In order to prevent the light from entering directly through the doors and windows, people will install curtains on the doors and windows. In view of the laborious and inconvenient manual opening and closing of the curtains, therefore, for the convenience of use, electric curtains have emerged as the times require.

Fig. 1 is a schematic plan view of an existing electric curtain 1, as shown in Fig. The drive rod 12, the screw hook 13 that is arranged on the left and right sides of the drive rod 12, hangs on the two curtains 14 on the hook 11 and the screw hook 13 respectively, and a motor 15 that is connected with the drive rod 12 , and the motor 15 is controlled by a photointerrupter 16 located at both ends of the inner surface of the frame seat 10 and the left and right sides near the center, and a switch 17 electrically connected to the motor 15 .

When the user presses the close key 171 on the switch 17, the motor 15 will drive the transmission rod 12 to rotate forward, so that the screw hook 13 originally located at the left and right ends of the transmission rod 12 will move to the center until the block is located near the center of the frame seat 10. When the photo-interrupters 161 on the left and right sides are on, the photo-interrupters 161 promptly transmit a signal to the motor 15 to stop the rotation, and the action of closing the curtain is completed; The motor 15 drives the transmission rod 12 to rotate in the opposite direction, so that the screw hooks 13 located at the left and right sides of the center of the transmission rod 12 move to the two ends of the transmission rod 12 respectively until the light interrupters 162 arranged at the two ends of the frame seat 10 are blocked, that is, Control motor 16 to stop rotating, and complete the opening action of curtain.

Although the above-mentioned electric curtain 1 has the function of electrically opening and closing the curtain, it has the following disadvantages in actual use:

1. The motor is easily burned due to overload:

Because the existing electric curtain 1 uses the photointerrupter 16 to determine whether the screw hook 13 driving the curtain has moved to a predetermined position, and then controls the motor 15 to stop rotating. When hooking, the motor 15 will still continue to drive the curtain 14 to open and close, but when the curtain 14 is pulled and cannot be smoothly driven to open and close, the motor 15 will stop. Continuously increasing the current flowing therethrough will easily cause the motor 15 to burn out due to overload.

2. There are many components, and the installation is cumbersome and complicated:

In order to control the screw hook 13 to stop at a predetermined position in due course in the existing electric curtain 1, photointerrupters 161, 162 must be installed on the two ends of the inner surface of the frame seat 10 and the left and right sides near the center, and each photointerrupter 161, 162 It is necessary to pull the wires to the motor 15 to control the motor 15 to stop in a timely manner, which makes the existing electric curtains have many components and makes the installation process very cumbersome; in addition, the installer must also have the relevant knowledge of electricity in order to correctly and smoothly pull the wires. Not suitable for ordinary consumers.

The main purpose of the utility model is to provide a motor drive device for electric curtains, which can protect the motor from being burnt due to overload in a timely manner.

In order to achieve the above purpose, the utility model adopts a new type of motor drive device for electric curtains. The main features of the motor drive device are a drive circuit for driving the motor, a controller for controlling the motor to stop and forward and reverse rotation, A current limiting circuit that controls the current flowing into the drive circuit, and an overload detection circuit that detects the output current of the circuit and sends a control signal to the controller to stop the motor in a timely manner. By controlling the opening and closing of the motor of the electric curtain, the curtain is controlled The opening and closing action of the motor can prevent the motor from being burned due to overload.

The motor drive device of the electric curtain of the present utility model is described in detail below through the preferred embodiment and the accompanying drawings:

Fig. 1 is a schematic diagram of the use state of the existing electric curtain.

Fig. 2 is a schematic plan view of a preferred embodiment of the present invention.

FIG. 3 is a circuit block diagram of a motor driving device in a preferred embodiment of the present invention.

FIG. 4 is a detailed circuit diagram of a motor drive device in a preferred embodiment of the present invention.

FIG. 5 is a diagram of a current limiting circuit and an overload detection circuit of a motor drive device according to another preferred embodiment of the present invention.

Fig. 2 is a schematic plan view of an electric curtain in a preferred embodiment of the present invention. The electric curtain 2 mainly includes a frame seat 20, a transmission rod 23 disposed in the frame seat 20, a motor 26 that can drive the transmission rod 23 to rotate, And components such as two pieces of curtain cloth 25 that can be opened and closed by the transmission rod 23; wherein, the bottom side of the frame seat 20 is provided with a chute 21, and a number of hooks 22 are slid on the chute 21, and the transmission rod 23 Divided into left and right sections from the middle and provided with threads in different directions, and a screw hook 24 is respectively screwed on the left and right sides of the transmission rod 23, and the curtain cloth 25 is hooked on the hook 22 and the screw hook 24 respectively; The running of 26 is controlled by motor drive unit 3.

Figure 3 is a circuit block diagram of a motor drive device 3, which includes a drive circuit 31, a controller 32, a current limiting circuit 34 located between the drive circuit 31 and an external power supply 33, and An overload detection circuit 35 is arranged between the controller 32 and the current limiting circuit 34 .

Shown in Fig. 4 is the detailed circuit diagram of motor drive circuit 3, wherein:

The drive circuit 31 includes a motor forward drive circuit composed of a group of triodes Q4, Q5, Q6, and a motor reverse drive circuit composed of a group of triodes Q7, Q8, Q9, and is electrically connected to the motor 26 respectively to Control the motor forward and reverse according to different control signals.

Controller 32 is electrically connected with above-mentioned drive circuit 31, and it comprises a microprocessor 321, and a group of manual switches 322 and a remote control receiver 323 that are electrically connected with microprocessor 321 respectively, make microprocessor 321 can be according to manual switch 322 or the control signal sent by the remote control receiver 323 controls the drive circuit 31 to drive the motor to perform forward, reverse or stop actions.

Current-limiting circuit 34 is arranged between above-mentioned drive circuit 31 and an external power supply 33, and it mainly comprises a PNP triode Q2 that is electrically connected with external power supply 33 and drive circuit 31 respectively with emitter plate, collector and a reverse connection to Q2 The zener diode ZD1 between the emitter plate and the base, and the zener diode ZD1 will maintain a constant voltage V _ZD1 due to the reverse connection, so that when the collector of the triode Q2 flows to the current I _L of the drive circuit 31 due to the motor 26 When the load becomes larger and gradually increases to a certain value, so that the sum of the voltage drop of the resistor R8 and the emitter and base voltage V _EB of the transistor Q2 approaches the voltage V _ZD1 of the Zener diode ZD1, the collector current of the transistor Q2 _IC will be pulled down immediately, so that the current I _L flowing to the driving circuit 31 cannot continue to rise, so as to prevent the motor 36 from being burnt due to the excessive current flowing through it. In addition, in order to supply stable DC power to the motor 26 , a rectifying and stabilizing circuit 36 composed of bridge rectifiers D1 , D2 , D3 , D4 and a voltage stabilizer 361 is provided between the external AC power supply 33 and the current limiting circuit 34 .

The overload detection circuit 35 is electrically connected to the above-mentioned current limiting circuit 34 and the controller 32 respectively, and it includes a collector connected to the microprocessor 321 of the controller 32 and a base connected to the triode Q2 collector of the current limiting circuit 34. Transistor Q3, and a resistance R12 that is electrically connected with the collector of triode Q3 to provide a voltage signal, like this, when motor 26 runs normally, the current _IL that current limiting circuit 34 provides is enough to drive motor 26, this moment triode Q2 The emitter of the triode Q3 gets a high voltage and divides the voltage through the resistors R10 and R11 to turn on the triode Q3, and the low voltage signal obtained by the collector of the triode Q3 is sent to the microprocessor 321 of the controller 32 to indicate that the motor is running normally; When the motor 26 is overloaded so that the current limiting circuit 34 operates, the current _IL provided by the transistor Q2 is reduced, and the emitter voltage of the transistor Q2 is relatively low, so that the voltage divided by the resistors R10 and R11 will not be enough to conduct The triode Q3 cuts off the triode Q3. At this time, the positive 5 volt high voltage signal obtained by the collector of the triode Q3 through the resistor R12 from the voltage regulator 361 informs the microprocessor 321 that the motor 26 has been overloaded.

As shown in Figures 2-4, when the user presses the off key of the remote control transmitter 4 or the manual switch 322, the controller 32 immediately sends a forward rotation control signal to start the forward rotation drive circuit of the drive circuit 31 and drives the motor 26 to drive The transmission rod 23 rotates in the forward direction, so that the screw hooks 24 screwed on both sides of the transmission rod 23 move relatively due to the different screw designs of the transmission rod 23, and the curtain cloth 25 is pulled by the hook 22 to spread out to cover the window surface , at this time, the high voltage obtained by the emitter of the triode Q2 can be detected by the overload detection circuit 35, and at the same time the overload detection circuit 35 outputs a low voltage signal to the controller 32 to inform the controller that the motor 26 is in normal operation at present, and when the screw When the movable hook 24 moves to the middle of the transmission rod 23 and hits the block 27, the transmission rod 23 cannot continue to rotate. At this time, the motor 26 is blocked and the current _IL is gradually increased to a certain degree, and the current limiting circuit 34 is activated. And make the current I _L drop to the range that the motor 26 can bear. At this time, the low voltage obtained by the emitter of the triode Q2 can be detected by the overload detection circuit 35. At the same time, the overload detection circuit 35 outputs a high voltage signal to inform the controller 32 to stop the motor 26. Running, that is to complete the closing action of the curtain; similarly, when the user wants to open the curtain and transmits a reverse control signal to the controller 32, the reverse drive circuit of the drive circuit 31 is activated so that the motor 26 drives the transmission rod 23 to reverse Rotate, the two screw hooks 24 in the middle of the transmission rod 23 move in the opposite direction, and the curtain cloth 25 is pushed back to the two sides of the transmission rod 23, and the overload detection circuit 35 outputs a low voltage signal to inform the controller 32 that the motor 26 is in the In the normal operation state, when the screw hook 24 retreats to the limit on both sides of the transmission rod, the current limiting circuit 34 will be activated due to the overload of the motor 26, and the current _IL flowing through the motor 26 will be reduced, and the overload detection circuit 35 will output a The high-voltage signal notifies the controller 32 to stop the motor 26 to complete the opening action of the curtain.

Therefore, using the circuit working principle of the above-mentioned motor drive device 3, when the motor 26 is driving the transmission rod 23 to rotate to open and close the curtain, if the curtain cloth 25 is accidentally hooked or pulled so that it cannot move forward with the rotation of the transmission rod 23 At this time, in order to overcome the resistance, the current I _L flowing through the motor 26 will rise, but if the current I _L continues to rise to a certain level, the motor 26 cannot overcome the external force or the motor 26 has reached the limit. At this time, in order to avoid When the motor 26 burns out due to overload, the current limiting circuit 34 will start, and the current I _L will be reduced to the range that the motor 26 can withstand. At this time, the overload detection circuit 35 detects a low voltage signal and notifies the controller 32 to The motor 26 stops running, so that the motor 26 can be protected in good time, and the curtain cloth 25 is prevented from being torn due to continuous pulling.

In addition, please refer to Fig. 5, the current limiting circuit 34 and the overload detection circuit 35 in the above-mentioned embodiment can also be replaced by the current limiting circuit 34' and the overload detection circuit 35' shown in Fig. 5, the current limiting circuit 34' The difference with 34 is that the current limiting circuit 34' replaces the Zener diode ZD1 of the current limiting circuit 34 with an adjustable resistor VR1, so that the size of the load current I _L can be adjusted according to the needs of different load circuits; and the overload The difference between the detection circuit 35' and 35 is that the overload detection circuit 35' connects an adjustable resistor VR2 in series between the voltage divider resistors R10 and R11, so that the voltage divider value of the resistor R11 can be randomly adjusted according to the needs of different load circuits, so as to Change the overload current setting value of the load circuit.

As can be seen from the above embodiments and with illustrations, the utility model does have the following advantages and functions:

1. Effectively protect the motor so that it will not be burned due to overload:

The utility model can properly limit the current flowing through the motor 26 and detect the running state of the motor at any time through the setting of the current limiting circuit 34 and the overload detection circuit 35, and can timely control the opening and closing of the curtain to make it smoothly positioned When the hook card makes the motor 26 unable to smoothly drive its opening and closing, the motor 26 can be stopped immediately, and the function of protecting the motor from burning due to overload is indeed achieved.

2. Effectively simplify the components and installation procedures of electric curtains:

It can be seen from the above embodiments that the electric curtain 2 only needs to install the motor drive device 3 of the present utility model, that is, the purpose of controlling the opening and closing of the curtain 25 can be easily achieved. It is convenient and easy, even ordinary users who do not understand electricity related knowledge can install it by themselves, and it is very easy to use or install.

Claims (8)

1. A motor drive device for an electric curtain, wherein the electric curtain includes a frame seat, a transmission rod arranged in the frame seat, a motor that can drive the transmission rod to rotate, and a motor that can be opened and closed with the transmission rod. Components such as curtain cloth, the above-mentioned motor is controlled by a motor drive device, which is characterized in that: the motor drive device includes a drive circuit electrically connected to the above-mentioned motor to drive the motor to drive the transmission rod to run; a controller is connected to the above-mentioned drive circuit To control the motor to stop and rotate forward and reverse; a current limiting circuit, set between the above-mentioned drive circuit and an external power supply, to limit the current flowing into the drive circuit from the external power supply; and an overload detection circuit, respectively connected to the above-mentioned current limiting The circuit and the controller are electrically connected to detect the output current of the current limiting circuit, and when the output current exceeds a preset value, a control signal is sent to notify the controller, so that the control drive circuit stops the motor from running. 2. The motor drive device for electric curtains as claimed in claim 1, wherein the drive circuit includes a forward drive circuit for driving the motor to run forward and a reverse drive circuit for driving the motor to run in reverse. 3. The motor drive device for electric curtains as claimed in claim 1 or 2, wherein the controller includes a microprocessor that controls the above-mentioned drive circuit according to the control signal, and the control signal comes from a and microprocessor In addition to the manual switch electrically connected to the appliance, a remote control receiver electrically connected to the microprocessor can be additionally provided so that the control signal comes from a remote control transmitter. 4. The motor drive device for electric curtains according to claim 1 or 3, wherein a rectification and voltage stabilization circuit is provided between the external power supply and the current limiting circuit. 5. The motor drive device for electric curtains as claimed in claim 4, wherein the current limiting circuit mainly includes a PNP transistor electrically connected to an external power supply and a drive circuit with an emitter and a collector respectively, and a transistor connected to the Zener diode between the collector and base of the PNP transistor. 6. The motor drive device for electric curtains as claimed in claim 1 or 5, wherein the overload detection circuit mainly includes an NPN transistor electrically connected to the controller and the current limiting circuit with the collector and the base respectively, and A resistor electrically connected to the collector of the NPN transistor. 7. The motor driving device for electric curtains as claimed in claim 5, wherein the zener diode of the current limiting circuit can be replaced by an adjustable resistor. 8. The motor drive device for electric curtains according to claim 6, wherein an adjustable resistor electrically connected to the PNP transistor can be connected in series between the two voltage divider resistors of the overload detection circuit.

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