GB2266789A

GB2266789A - Overload protection means.

Info

Publication number: GB2266789A
Application number: GB9209595A
Authority: GB
Inventors: Chi-Sheng Hsieh
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-05-02
Filing date: 1992-05-02
Publication date: 1993-11-10
Anticipated expiration: 2012-05-02
Also published as: GB2266789B; GB9209595D0

Abstract

Overload of the motors 14, 15 opening and turning a vertical blind is prevented by monitoring the extent of opening/ turning of the blinds following instructions from an operator, and stopping further operation once the blinds are determined to have reached an overload position eg. fully open or rotated. The overload positions can be input by the operator 45 or learnt in an automatic set up mode. <IMAGE>

Description

AN AUTOMATIC VERTICAL BLIND CONTROLLER WITH MEMORY The present invention relates to an automatic vertical blind controller with memory, particularly an innovative design of automatic vertical blind controller with memory.

Vertical blinds have been widely used in home and office because they can adjust indoor lighting from outdoor lighting source easily. However, the conventional vertical blind, such as the manual/automatic vertical blind controller disclosed in the US Patent 4956588 has a lot of defects, as follows: 1. Fig. 5 of the drawings of this specification is a circuit diagram for an infrared receiver circuit disclosed in the above US patent, R5 and R6 are semiadjustable carbon resistors for adjusting the base voltage, R1 and R2 are resistors to pick up an overload signal from driving circuit ICs 53 and 54 in order to provide a voltage to a motor overload detection circuit 60. However, because R5 and R6 are adjustable, it is necessary to adjust the sensitivity in every use. This is not convenient and adjustment may become inaccurate easily.

2. The driving circuit ICs 53 and 54 normally can withstand a current of about 1.5 A, but the DC motor (M1 or M2) will continue to run after the vertical blind reaches the end and, hence, overload will occur, which results in an increase of current to the ICs 53 and 54, and consequently burning out of the ICs 53 and 54, or even fire.

3. The rail of the vertical blind will become oxidised and accumulate dust after prolonged use.

There is then more friction on the rail and consequently the load becomes greater. Therefore, taking the load of the electronic circuit into consideration, the maximum length of vertical blind practicable is usually about 2 to 3 meters. Hence, the prior art is not practical.

In view of the above defects, the inventor has created an automatic vertical blind controller with a memory to eliminate the said defects. It can be a practical and advanced device, particularly an automatic vertical blind controller with an automatic/manual operated memory for control of vertical blind turning and movement automatically by referring to reference data in the memory representing the upper limit degree of turning/movement set up by its user, comprising an outer casing, an inner casing and a control circuit board, in which the control circuit board is composed of an infrared receiver circuit, a manually-operated push-button control circuit, a single-chip microprocessor, two relay motor driving circuits, a music control circuit, and a power supply; the inner casing has two DC motors each incorporating a reducing gear, two light sensors within it, and a chain pulley, a cord pulley, two light detectors, two guide wheels, and two press wheels outside the inner casing except the two light detectors are located below the chain pulley and the cord pulley within the inner casing; the control circuit board is located at the rear part of the inner casing; the outer casing is incorporated with five push buttons and has a size just for fitting of the inner casing.

An embodiment of the invention will now be described by way of example with reference to Figures 1 to 4 of the drawings, in which: Fig. 1 is a perspective and fragmental view of an automatic vertical blind controller with memory, Figs. 2A to 2C are a flow chart for automatic memory function of a single-chip microprocessor of the controller, Figs. 2D to 2E are a flow chart for manual memory function of the single-chip microprocessor, Fig. 3 is a block diagram for function of a control circuit board of the controller, and Fig. 4 is a circuit diagram for the control circuit board.

As shown in Fig. 1, a perspective fragmental view of an automatic vertical blind controller with memory according to the present invention, the controller is composed of an inner casing 11, an outer casing 12 and a control circuit board 33. The inner casing 11 has two holes for installation of two DC motors 14,15. The upper DC motor 14 is fitted with a chain pulley 4, and the lower DC motor 15 is fitted with a cord pulley 16.

There is a circular light sensor 80 beneath the chain pulley 4 and another circular light sensor 80' beneath the cord pulley 16. Two pulleys 17,18, each connecting to an end of a rectangular plate 19,20, are located at appropriate positions. A spring 23 is installed between two rectangular plates 19,20 so as to pull two press wheels 21,22 inwards in order to maintain the press wheels 21,22 within the groove of the cord pulley 16, and to press against the cord pulley 16 directly so that a cord 42 of any diameter can be placed and maintained therein under pressure.

The inner casing 11 has two small holes 82,82' beneath the light sensors 80,80', within each of which a light detector 81,81' is installed to detect a light sensing clock signal generated by the light sensors 80,80' through the small holes 82,82' upon rotation of the chain pulley 4 and the cord pulley 16. These clock signals are received by the light detectors 81,81', and then transmitted to a single-chip microprocessor 100 on the control circuit board 33 for processing (as shown in Fig. 3). An infrared receiver 31 is used to receive a signal from a remote infrared transmitter. The outer casing 12 includes five push buttons 45 for manual setting of memory or control instead of the remote infrared transmitter in the absence of the remote infrared transmitter.The outer casing 12 is dimensioned just to fit over the inner casing and has a display opening 34 and two screw holes 35,35' for fitting to the inner casing 11 with two bolts. A power source socket 36 is for connecting to a power source.

Fig. 2A is a flow chart for automatic function control with the single-chip microprocessor. As shown in the figure, upon operation of each vertical blind controller, in order to avoid overload which occurs frequently in the conventional vertical blind controller, the controller turns to automatic memory mode automatically if its STOP key is not pressed within 3 to 4 seconds after it is turned on or reset after power failure, the vertical blind is moved outwards continuously until overload occurs as a reset position and a point to proceed to leftward or rightward turning. At this moment, no point of overload is stored in the memory. Then, the vertical blind proceeds to turn leftwards till overload occurs.

This process is to reset the memory. The vertical blind is then turned rightwards. At this moment, the memory system 101 in the single-chip microprocessor 100 beings to save the degree of turning until overload occurs, and the point where the overload occurs is saved in the memory system 10 as a reference for the end of turning of the vertical blind in future operation. The vertical blind is then turned leftward and the single-chip microprocessor sets the vertical blind to turn leftward for 450 to assure smooth moving of the vertical blind. Then, the vertical blind begins to move backwards, a counter begins counting until overload occurs, which means that the vertical blind has reached the start position, and such position is a reference for start or stop of the vertical blind, and is saved in the memory system 101 for comparison in further operation of the vertical blind.

Upon the first operation of the vertical blind, if the STOP key is pressed within 3 to 4 seconds after it is turned on, it turns to manual mode automatically.

Please refer to Fig. 2B for a flow chart for manual control of memory functions. Upon starting of the single-chip processor, a period of 10 minutes is set for manual operation. If the manual memory system is not activated within this 10-minute period, the microprocessor 100 activates the automatic memory system (as described above). Upon manual operation, the push buttons 45 are used. As shown in the flow chart, there are three adjustment modes: N for movement control, Y for activation of manual memory control, and B for disabling of manual memory control.

The N mode is for control of the vertical blind with push buttons 45 manually, upon which the single-chip microprocessor 100 will not operate with the memory.

To activate Y mode, an adjustment key (out, in, left or right) and the STOP key are pressed simultaneously, the single-chip microprocessor 100 erases the memory and makes the memory system 101 start memorizing. By pressing the STOP key when the vertical blind reaches the desired position, the stop point is saved in the memory system 101 as basis for further operation.

After setting up of stop points, the manual memory control can be disabled by B mode, that is, by pressing the STOP keys five times consecutively, the microprocessor disables the manual memory control.

Upon disabling of the manual memory control, the memory is checked. If no data is saved in the memory, the automatic memory is activated. If there is data in the memory, the controller enters a standby state to avoid overload in automatic memory mode when the controller is turned on.

Upon receipt of a remote infrared signal or signal from any of the push buttons, the single-chip microprocessor 100 distinguishes the signal and performs the action required. For instance, if the signal is to move the vertical blind outwards, the lower motor 15 is caused to run in the normal direction, the single-chip microprocessor 100 starts counting, plays music, and compares the counting with the reference data saved in the vertical blind.

Movement of the vertical blind continues until the counting is equal to the reference data, but the movement can be interrupted at any time in the course of moving by pressing of the STOP button. For backward movement of the vertical blind, the lower motor 15 is caused to run in the reverse direction, and the counting is in reverse order. For leftward turning of the vertical blind, the upper motor 14 is caused to run in the normal direction and the counting is in the normal order. For rightward turning of the vertical blind, the upper motor 14 is caused to run in reverse direction, and the counting is in reverse order.

Though overload occurs in the automatic memory mode, it happens only at the start-up, and the overload is for the purpose of setting up an overload point, which is applied as a reference for all operations thereafter. No further overload will occur.

Therefore, in comparison with the conventional vertical blind controller, much less overload will happen, and consequently the service life of the vertical blind can be prolonged.

Please refer to Fig. 3 for a block diagram of the control circuit for the present invention. When the power source system 210 is ON and any of the push buttons 45 on the outer casing 12 or any button 2111 on the remote infrared controller is pressed, the cord pulley 16 or the chain pulley 4 is activated to rotate, the two light sensors 80,80' detect rotation of the pulleys 16,4 and a clock signal is generated. The clock signal is transmitted to the single-chip microprocessor 100 in the control circuit board 33 for saving or determination of the course of setting. Upon receipt of the signal, the microprocessor 100 orders the vertical blind to operate, and starts the motors 14,15. At the same time, the microprocessor 100 instructs a music control circuit 217 to play music via a speaker 218.The single-chip microprocessor 100 begins to set the memory system to accumulate counting, and compares the counting with the reference set and checks if it exceeds the reference data. If it does not exceed the reference data, a pushing of the STOP button can stop the vertical blind, and then further pushing of the button 45 or the button 2111 on the infrared remote controller can cause the vertical blind to continue its operation until the reference data is reached. Then, the microprocessor 100 sends a stop signal to a relay motor driving circuit 214 to stop the motors 14,15 without occurrence of overload problem.

Fig. 4 is a circuit diagram for the control circuit of the vertical blind controller. As shown in Fig. 3, the control circuit includes a single chip microprocessor 100, an infrared remote control receiver system 211, push buttons 45 on the outer casing, two relay motor driving circuits 214, two DC motors 14,15, two light sensors 80,80', and a music control circuit 217. The manually operated push buttons 201 to 205 are to send signals to the microprocessor 100, in which the angle control push button 201 is to control the rightward turning angle of the vertical blind, another angle control push button 202 is to control the leftward turning angle of the vertical blind, the close control push button 203 is to move the vertical blind inwards, the open control push button 204 is to move the vertical blind outwards, and the stop push button is to stop motor operation.As shown in the drawings, the relay motor driving circuit 214 is to cause the upper DC motor 14 to control leftward and rightward turning of the vertical blind, and the lower DC motor 15 to control inward and outward moving of the vertical blind. After receipt of the signal from the singlechip microprocessor 100, ICs U8 and U9 in the relay motor driving circuit 214 cause the signal wire W2 low, and the other signal wires W2, W3 and W4 high in order to activate a relay A, the contacts jump to NOI and NO2, but all other relays A', B and B' remain inactive and their contacts are at NC1, NC2', NC3, NC4, NC3' and NC4' respectively. When the relay A is activated, the upper DC motor 14 is driven to run in the normal direction so that the blades of the vertical blind are turned leftwards. Similarly, when W3 is low, W1, W2 and W4 are high, the relay B is activated, the contacts jump to NO3 and NO4, the lower DC motor 15 is driven to run in the normal direction so that the vertical blind is moved outwards, and a signal wire W5 sends a signal to the music control circuit 217 to play music, and causes a transistor Q2 to activate music IC U14 to provide audible music from a speaker 218. In this way, when the vertical blind is moving, there is music. The music stops as soon as either motor stops. When the relay A' is activated, the upper DC motor 14 is driven to run in the reverse direction so that-the blades of the vertical blind are turned rightwards. When the relay B' is activated, the lower DC motor 15 is driven to run in the reverse direction to move the vertical blind inwards.The use of relays to control the motor running direction is much superior to the conventional electronic circuit to drive a motor directly. LI-1 and LI-2 receive clock signals from the light sensors 80,80'. The light sensors 80,80' detect light passing through two holes 82,82' when the cord pulley 16 and the chain pulley 4 are rotated. Consequently, the light is detected by the light detectors 81,81' to fire a clock signal which is then received by LI-1 and LI-2 on the clock signal control circuit 261 of the control circuit board 33, and is then transmitted to the microprocessor 100 as a reference of the relay motor driving circuit for further driving of the motors 14,15.Moreover, with the memory system in the singlechip microprocessor 100, there is no limit on the length of vertical blind, and the motor will not continue operation after occurrence of overload.

Therefore, the present invention is a novel and practical device for control of vertical blinds.

As described above, the present invention provides a practical and advanced controller for vertical blinds. It has two light sensors to detect signals upon rotation of the cord pulley and chain pulley for disposition in a memory of a single-chip microprocessor in order to control motor operation, and to prevent from overload except during its operation for the first time when extent becoming overload is unknown.

Moreover, relays are used to drive motors, to prevent overcurrent such as occurs in the conventional electronic driving circuit, it does not impose any limit on the length of vertical blind to eliminate the need of modifying control circuit upon change of length as required in the prior art, which may result in overload if its control circuit remains unchanged. The present invention uses light sensors to detect clock signals for control of vertical blind movement, there is no limit on length of vertical blind, and hence the present invention is applicable to vertical blind of any length. In addition to the above features, operation of the vertical blind is accompanied by music in order to provide nice music when adjusting the vertical blind for appropriate lighting purpose.

Many changes and modifications in the above described embodiment of the invention can, of course, be carried out without departing from the scope thereof.

Claims

1. An automatic vertical blind controller with memory, comprising - first and second drive motors for turning and driving a vertical blind, respectively, - means for detecting rotation of each drive motor, - means for inputting user commands for turning and driving a said blind, - control means responsive to the input means and the rotation-detection means, the control means comprising microprocessor means and a relay circuit for driving each drive motor, the microprocessor means including memory means for storing reference data representing an overload position, wherein, in operation, the input means sends a command signal to the microprocessor means which, upon detection of rotation of one or other of the drive motors, causes the appropriate relay circuit to drive its respective motor to cause the blind to turn or move, as required, the degree of blind turning or movement being counted and compared with the reference data in the memory means in order to control the degree of turning, opening or closing of the blind.

2. An automatic vertical blind controller with memory, comprising - an inner casing having two DC motors each having a reducing gear, two light sensors, a chain pulley, a cord pulley, two light detectors beneath the chain pulley and the cord pulley respectively, two guide wheels, and a control circuit board; - an outer casing with push buttons on it and having a size just to fit over the inner casing; - a control circuit board including an infrared receiver circuit, a button control circuit, a single chip microprocessor, two relay motor driving circuits, a light signal receiver circuit, and a music control circuit; in which the single-chip microprocessor has a memory for storing reference data representing an overload position; the infrared receiver circuit receives a signal from an infrared remote controller or push button on the outer casing and sends a signal to the single-chip microprocessor which, when the light sensors in the inner casing detect a clock signal upon rotation of the cord pulley and the chain pulley, causes the appropriate relay motor driving circuit to drive its respective motor which consequently drives the vertical blind to turn or move, and sends a signal to the music control circuit to play music; and the degree of vertical blind turning or movement is counted and compared with the reference data in the memory to control degree of turning, opening, and closing of the vertical blind.

3. An automatic vertical blind controller with memory, the controller being substantially as hereinbefore described with reference to the drawings.