CN111352291A - Projection curtain control method with one-key alignment function - Google Patents
Projection curtain control method with one-key alignment function Download PDFInfo
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- CN111352291A CN111352291A CN202010351936.4A CN202010351936A CN111352291A CN 111352291 A CN111352291 A CN 111352291A CN 202010351936 A CN202010351936 A CN 202010351936A CN 111352291 A CN111352291 A CN 111352291A
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- curtain
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
- G03B21/00—Projectors or projection-type viewers; Accessories therefor
- G03B21/54—Accessories
- G03B21/56—Projection screens
- G03B21/58—Projection screens collapsible, e.g. foldable; of variable area
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- Curtains And Furnishings For Windows Or Doors (AREA)
Abstract
The invention discloses a projection curtain control method with one-key alignment function, which comprises the following steps: entering a position setting mode, determining the position of a lower boundary, determining a reference current and an overproof range, and detecting A by a high-precision metering chip2Excess ((1-B) A)1，(1+B)A1) When the screen is used for a long time, the problem that an alternating current synchronous motor cannot adopt a locked rotor mode to set an upper boundary is solved, the control precision is higher, the cost is lower, the screen is quieter, only a lower boundary needs to be set, the most appropriate upper boundary is automatically found, only one key is needed to correct the position, and the screen setting operation is simplified to the utmost extent.
Description
Technical Field
The invention belongs to the field of projection curtain equipment, and particularly relates to a projection curtain control method with a one-key alignment function.
Background
When the projection curtain is not used, the curtain needs to be rolled up in order to save office space and keep the curtain clean. At present, mechanical movable curtain travel limit controllers are generally adopted in the market to adjust the upper and lower boundary positions of a curtain, and due to the defects of high cost, easiness in damage, complex adjustment and the like, the traditional electric curtain travel limit controllers are replaced by electronic methods in the current curtain control industry. At present, curtain control methods on the market are mostly set and stored upper boundary points and lower boundary points, and the positions of the upper boundary points are easy to be rolled or exposed too much due to difficult alignment. Meanwhile, after long-term use or when the user is pulled manually, the positions of the upper boundary and the lower boundary are easy to shift, and only the upper boundary and the lower boundary can be reset at the moment.
This company has researched and developed and applied for a series of projection curtain electronic control modes, wherein CN110286556A a curtain control method and control mechanism, disclose one kind and adopted direct current gear motor, the curtain lower border passes through operator's free position, the upper border passes through current detection circuit and confirms the position, the upper limit critical point of artifical affirmation has been saved, can confirm the most accurate position, and all detect direct current gear motor's electric current during the rolling of every time, stop the rolling when the electric current overloads, can avoid the curtain to use for a long time and take place the skew, lead to the too much problem of rolling overexposure.
In the subsequent research and development process, it is desirable to use an ac synchronous motor as the curtain driving power, mainly because:
1) the cost of the alternating current synchronous motor is lower than that of the direct current synchronous motor, the purchase cost of the alternating current speed reducing motor is about 20 yuan, and the purchase cost of the direct current speed reducing motor is 50-60 yuan due to the fact that a voltage stabilizer and a voltage reducer are added;
2) the initial rotating speed of the alternating current synchronous motor is about 300r/min, the initial rotating speed of the direct current speed reducing motor is about 2000r/min, and the alternating current synchronous motor is smaller in noise and is more silent;
3) the alternating current synchronous motor can adopt a zero-crossing circuit to detect the number of alternating current pulses, so that the number of revolutions of synchronous rotation of the motor is obtained, and the control is more accurate.
Meanwhile, the present company found that the following problems exist:
1. when the DC speed reducing motor is locked, the current value reaches multiple times of the original value, the detection is simpler, and when the AC synchronous motor is locked, the current is only disturbed by 5 percent, for example, the normal current value is 1A, the current is 0.95A or 1.05A when the lock is rotated, and the current detection circuit in the prior art can not effectively detect the lock;
2. the projection screen is sold to various places, and the voltages under various use environments are different, so that the normal working current and the locked-rotor current are changed, for example, the current is 1A when the projection screen is normally operated at 220V, and the locked-rotor current is 0.95A or 1.05A; the current is 0.8A when the motor normally runs at 180V, and the locked-rotor current is 0.75A or 0.85A;
3. preceding curtain is when the rolling, and the rolling stops all to rely on direct current motor stall at every turn, uses for a long time and reduces motor and current detection circuit life easily.
Disclosure of Invention
Aiming at the defects in the prior art, the technical problem to be solved by the invention is to save cost, when the AC synchronous motor and the DC motor are adopted to control the operation of the curtain, the locked-rotor current of the AC synchronous motor is too small and is difficult to detect, the detection of the locked-rotor current is easily influenced when the voltage changes, the detection is required when the locked-rotor current is wound every time, and the service lives of the motor and the current detection circuit are shortened.
In order to solve the above technical problem, the present invention provides a method for controlling a projection screen with a one-key alignment function, comprising:
a calibration method is provided,
after the machine is started, a red indicator light of the controller is turned on, the controller enters a normal working state, a key 10S on the controller is pressed for a long time, a blue indicator light is turned on, and the controller enters a position setting mode;
the curtain is adjusted to the proper lower boundary by the up key and the down key on the controller,
rated current A at rated voltage of 220V0The MCU singlechip detects the current voltage value through a high-precision metering chip, compares the current voltage value with the rated 220V voltage, and converts the current value into a reference current value A1Setting the standard exceeding percentage as B and the actual current value as A2High precision metrology chip probe A2Excess ((1-B) A)1，(1+B)A1) When the range is within the range, the locked rotor is judged,
long press up key 3S, enter length automatic setting mode, motor rotation, curtain rolling, bottom bar up movement, touch curtain box, bottom bar meets and hinders, motor current is disorderly, high accuracy measurement chip detects A2Excess ((1-B) A)1，(1+B)A1) When the range is within the range, the locked rotor is judged; the motor stops running, the curtain moves downwards for a safe length, the position is set as an upper boundary, the upper boundary is stored, the setting of the upper boundary and the lower boundary of the curtain is finished at the moment,
the length of the curtain, namely the distance between an upper boundary and a lower boundary is set as L, the length of the curtain moving from the set lower boundary to the locked rotor is set as D, the safe length of the curtain retraction is set as q, L is D-q,
a method for calculating the length of a curtain,
the driving motor is an alternating current synchronous motor, the number of revolutions of the alternating current synchronous motor is in a direct proportion relation with the number of sine waves of alternating current, a zero-crossing detection circuit is adopted to detect the number of sine waves in the alternating current, the curtain moves from a set lower boundary to a locked rotor length D and a retracted safe length q, the curtain is converted into corresponding sine wave number, the number of the sine waves of the safe length is set to be N, and the number of the sine waves retracted after locked rotor is subtracted from the number of the corresponding raised sine waves of the used length of the curtain;
a method for controlling the working state of a motor,
waiting for a controller starting signal, judging whether the controller is positioned at a lower boundary when the controller starts to move downwards, and when the controller does not position at the lower boundary, the AC synchronous motor rotates forwards, the curtain moves downwards, waiting for a controller stopping signal or the position of the lower boundary, and stopping when no stopping signal reaches the lower boundary; when moving upwards, judging whether the screen is at the upper boundary or not, when not at the upper boundary, the AC synchronous motor rotates reversely, the screen moves upwards, waits for the stop signal of the controller or the position of the upper boundary, when no stop signal reaches the upper boundary, the screen stops,
when the displacement is carried out, one key is aligned,
when the position of the curtain deviates, such as the position deviation caused by artificial pulling of the curtain or long-time use, a one-key alignment function can be used, and the controller is pressed to designate a trigger button to enter an automatic reset state; the curtain firstly runs downwards for N sine waves, so that the problem that the starting current is large when the curtain is at the top and directly runs upwards is solved; then the curtain moves upwards, stops after detecting the locked rotor, moves N sine waves downwards to prevent the curtain from being in a tight state, finds an upper boundary at the moment, determines the position of a lower boundary according to the set length L,
the method of storing the location of the object,
in the running process, if a stop signal and a locked-rotor signal are encountered, relevant data are stored into a memory so as to be used in the next running process; when the power is off in the operation process, the power failure detection circuit stops the curtain after detecting that the voltage is low to a set value, relevant position data is stored in the memory, and the data is the curtain position information when the curtain is started next time.
Further, when the position setting mode is entered, the controller enters the position setting mode by long-pressing the controller up key 10S.
Further, in the length setting mode, after the lower boundary position is determined, the upward key 3S is pressed for a long time to enter the length automatic setting mode, and the controller moves upward to find the locked-rotor position.
Furthermore, when one key is used for alignment in the deviation process, the key on the remote controller is pressed for 5 seconds for a long time or the key on the remote controller is pressed for 6 times for a short time, and the automatic reset state is entered.
Further, the length setting can also be realized by firstly detecting the position of the upper boundary, then automatically descending the curtain, stopping pressing when the proper position of the lower boundary is reached, and storing the position of the lower boundary by pressing the down key for 6 seconds, thereby determining the using length of the curtain.
Furthermore, the controller comprises a key box and a radio frequency signal emitter which are connected with the single chip microcomputer through a lead, the radio frequency signal emitter is a remote controller, and the single chip microcomputer is connected with a radio frequency signal decoding unit.
Further, the safety length q is 5-50 mm.
Further, the high precision metering chip is model No. SSP 1837.
The working principle of the invention is as follows:
in order to use the alternating current synchronous motor, the invention detects current through an SSP1837 high-precision metering chip, compensates the current value when the voltage changes, and changes the reference current along with the voltage change.
The number of revolutions of the alternating current synchronous motor and the number of sine waves of alternating current are in a direct proportion relation, and a zero-crossing detection circuit is used for accurately measuring position change; the upper boundary of the curtain is based on the relative position of the curtain after the curtain moves upwards to meet the blockage, and the position is not changed, so that the curtain can return to the previously set position after finding the position.
The invention has the beneficial effects that:
1. the method is characterized in that an alternating current synchronous motor is adopted, a zero-crossing detection circuit is adopted to detect the quantity of sine waves, the sine waves are converted into the number of revolutions and the running length of the motor, and the length is measured by comparing the time of the direct current synchronous motor, so that the method is more accurate;
2. the AC synchronous motor is adopted, so that the cost is reduced and the noise is reduced;
3. the control method of the curtain is greatly simplified, and a lower boundary and an upper boundary are required to be respectively set for the traditional curtain; on the basis of improving the motion precision of the curtain, the invention can automatically find the upper boundary with proper length and safety only by setting the proper lower boundary according to the requirements of customers. In the traditional method, when the curtain is used for a long time or the upper and lower boundaries are changed by manual pulling, only the upper boundary and the lower boundary can be reset, which is more complicated; the invention only needs one key to correct the deviation, long presses the upper key of the remote controller for 5 seconds, or short presses the upper key for 6 times, enters the automatic reset state, can automatically find the positions of the upper boundary and the lower boundary, and simplifies the setting operation of the curtain to the utmost extent.
Drawings
FIG. 1 is a schematic diagram of the control steps of the curtain of the present invention during normal operation and power failure;
fig. 2 is a schematic diagram of a control procedure of one-touch alignment during offset according to the present invention.
Detailed Description
The details of the present invention are described below with reference to the accompanying drawings and specific embodiments.
As shown in fig. 1 and 2, a curtain control method includes:
the position-setting mode is entered into,
after the machine is started, a red indicator light of the controller is turned on, the controller enters a normal working state, a specified trigger button of the controller is pressed, a blue indicator light is turned on, and the controller enters a position setting mode;
the position of the lower boundary is determined,
the curtain is adjusted to the proper lower boundary by the up key and the down key on the controller,
a reference current and an out-of-standard range are determined,
rated current A at rated voltage of 220V0The MCU singlechip detects the current voltage value through a high-precision metering chip, compares the current voltage value with the rated 220V voltage, and converts the current value into a reference current value A1Setting the standard exceeding percentage as B and the actual current value as A2High precision metrology chip probe A2Excess ((1-B) A)1，(1+B)A1) When the range is within the range, the locked rotor is judged,
the length-setting mode is entered into,
the controller is pressed to designate a trigger button, the automatic length setting mode is entered, the motor rotates, the curtain is rolled, the bottom rod moves upwards to touch the curtain box, the bottom rod meets resistance, the current of the motor is disordered, and the high-precision metering chip detects A2Excess ((1-B) A)1，(1+B)A1) When the range is within the range, the locked rotor is judged; stopping the motor, moving the curtain downwards for a safe length, setting the position as an upper boundary, storing the upper boundary, finishing the setting of the upper boundary and the lower boundary of the curtain,
the length of the curtain, namely the distance between an upper boundary and a lower boundary is set as L, the length of the curtain moving from the set lower boundary to the locked rotor is set as D, the safe length of the curtain retraction is set as q, L is D-q,
a method for calculating the length of a curtain,
the driving motor is an alternating current synchronous motor, the number of revolutions of the alternating current synchronous motor is in a direct proportion relation with the number of sine waves of alternating current, a zero-crossing detection circuit is adopted to detect the number of sine waves in the alternating current, the curtain moves from a set lower boundary to a locked rotor length D and a retracted safe length q, the curtain is converted into corresponding sine wave number, the number of the sine waves of the safe length is set to be N, and the number of the sine waves retracted after locked rotor is subtracted from the number of the corresponding raised sine waves of the used length of the curtain;
the sine wave and zero-crossing detection circuit method can refer to a projection curtain limiting method and a limiting mechanism of CN110286554A applied by the company.
A method for controlling the working state of a motor,
waiting for a controller starting signal, judging whether the controller is positioned at a lower boundary when the controller starts to move downwards, and when the controller does not position at the lower boundary, the AC synchronous motor rotates forwards, the curtain moves downwards, waiting for a controller stopping signal or the position of the lower boundary, and stopping when no stopping signal reaches the lower boundary; when moving upwards, judging whether the screen is at the upper boundary or not, when not at the upper boundary, the AC synchronous motor rotates reversely, the screen moves upwards, waits for the stop signal of the controller or the position of the upper boundary, when no stop signal reaches the upper boundary, the screen stops,
when the displacement is carried out, one key is aligned,
when the position of the curtain deviates, such as the position deviation caused by artificial pulling of the curtain or long-time use, a one-key alignment function can be used, and the controller is pressed to designate a trigger button to enter an automatic reset state; the curtain firstly runs downwards for N sine waves, so that the problem that the starting current is large when the curtain is at the top and directly runs upwards is solved; then the curtain moves upwards, stops after detecting the locked rotor, moves N sine waves downwards to prevent the curtain from being in a tight state, finds an upper boundary at the moment, determines the position of a lower boundary according to the set length L,
the upper position of the curtain is based on the relative position of the curtain after the curtain moves upwards to meet the blockage, and the position is not changed, so that the curtain can return to the previously set position when the position is found.
The method of storing the location of the object,
in the running process, if a stop signal and a locked-rotor signal are encountered, relevant data are stored into a memory so as to be used in the next running process; when the power is off in the operation process, the power failure detection circuit stops the curtain after detecting that the voltage is low to a set value, relevant position data is stored in the memory, and the data is the curtain position information when the curtain is started next time.
In practical applications, when the controller enters the position setting mode, the controller enters the position setting mode by long-pressing the controller up key 10S.
In practical application, in the length setting mode, after the lower boundary position is determined, the upward key 3S is pressed for a long time, the automatic length setting mode is entered, and the controller moves upwards to find the locked-rotor position.
In practical application, when a key is used for alignment in deviation, the key on the remote controller is pressed for 5 seconds for a long time or pressed for 6 times for a short time, and the automatic reset state is entered.
In practical application, the length setting can also be realized by firstly detecting the position of the upper boundary, then automatically descending the curtain, stopping pressing when the proper position of the lower boundary is reached, and storing the position of the lower boundary by pressing the down key for 6 seconds, thereby determining the using length of the curtain.
In practical application, the controller comprises a key box and a radio frequency signal emitter which are connected with the single chip microcomputer through a lead, the radio frequency signal emitter is a remote controller, and the single chip microcomputer is connected with a radio frequency signal decoding unit.
In practical application, the safety length q is 5-50 mm.
In practical applications, the high-precision metering chip is model SSP 1837.
In conclusion, the invention overcomes the problem that the AC synchronous motor can not set the upper boundary by adopting a locked-rotor mode, has higher control precision, lower cost and more silence, sets the curtain only by setting the lower boundary and automatically finds the most appropriate upper boundary, only needs one-key correction when the curtain is used for deviation for a long time, and simplifies the curtain setting operation to the utmost.
The foregoing illustrates and describes the principles, general features, and advantages of the present invention. It should be understood by those skilled in the art that the foregoing embodiments are merely illustrative of the technical spirit and features of the present invention, and the present invention is not limited thereto but may be implemented by those skilled in the art.
Claims (8)
1. A projection curtain control method with one-key alignment function is characterized in that: the method comprises the following steps:
the position-setting mode is entered into,
after the machine is started, a red indicator light of the controller is turned on, the controller enters a normal working state, a specified trigger button of the controller is pressed, a blue indicator light is turned on, and the controller enters a position setting mode;
the position of the lower boundary is determined,
the curtain is adjusted to the proper lower boundary by the up key and the down key on the controller,
a reference current and an out-of-standard range are determined,
rated current A at rated voltage of 220V0The MCU singlechip detects the current voltage value through a high-precision metering chip, compares the current voltage value with the rated 220V voltage, and converts the current value into a reference current value A1Setting the standard exceeding percentage as B and the actual current value as A2High precision metrology chip probe A2Excess ((1-B) A)1，(1+B)A1) When the range is within the range, the locked rotor is judged,
the length-setting mode is entered into,
the controller is pressed to designate a trigger button, the automatic length setting mode is entered, the motor rotates, the curtain is rolled, the bottom rod moves upwards to touch the curtain box, the bottom rod meets resistance, the current of the motor is disordered, and the high-precision metering chip detects A2Excess ((1-B) A)1，(1+B)A1) When the range is within the range, the locked rotor is judged; the motor stops running, the curtain moves downwards for a safe length, the position is set as an upper boundary, the upper boundary is stored, the setting of the upper boundary and the lower boundary of the curtain is finished at the moment,
the length of the curtain, namely the distance between an upper boundary and a lower boundary is set as L, the length of the curtain moving from the set lower boundary to the locked rotor is set as D, the safe length of the curtain retraction is set as q, L is D-q,
a method for calculating the length of a curtain,
the driving motor is an alternating current synchronous motor, the number of revolutions of the alternating current synchronous motor is in a direct proportion relation with the number of sine waves of alternating current, a zero-crossing detection circuit is adopted to detect the number of sine waves in the alternating current, the curtain moves from a set lower boundary to a locked rotor length D and a retracted safe length q, the curtain is converted into corresponding sine wave number, the number of the sine waves of the safe length is set to be N, and the number of the sine waves retracted after locked rotor is subtracted from the number of the corresponding raised sine waves of the used length of the curtain;
a method for controlling the working state of a motor,
waiting for a controller starting signal, judging whether the controller is positioned at a lower boundary when the controller starts to move downwards, and when the controller does not position at the lower boundary, the AC synchronous motor rotates forwards, the curtain moves downwards, waiting for a controller stopping signal or the position of the lower boundary, and stopping when no stopping signal reaches the lower boundary; when moving upwards, judging whether the screen is at the upper boundary or not, when not at the upper boundary, the AC synchronous motor rotates reversely, the screen moves upwards, waits for the stop signal of the controller or the position of the upper boundary, when no stop signal reaches the upper boundary, the screen stops,
when the displacement is carried out, one key is aligned,
when the position of the curtain deviates, such as the position deviation caused by artificial pulling of the curtain or long-time use, a one-key alignment function can be used, and the controller is pressed to designate a trigger button to enter an automatic reset state; the curtain firstly runs downwards for N sine waves, so that the problem that the starting current is large when the curtain is at the top and directly runs upwards is solved; then the curtain moves upwards, stops after detecting the locked rotor, moves N sine waves downwards to prevent the curtain from being in a tight state, finds an upper boundary at the moment, determines the position of a lower boundary according to the set length L,
the method of storing the location of the object,
in the running process, if a stop signal and a locked-rotor signal are encountered, relevant data are stored into a memory so as to be used in the next running process; when the power is off in the operation process, the power failure detection circuit stops the curtain after detecting that the voltage is low to a set value, relevant position data is stored in the memory, and the data is the curtain position information when the curtain is started next time.
2. The method as claimed in claim 1, wherein the method comprises the steps of: when entering the position setting mode, the controller enters the position setting mode by long-pressing the controller up key 10S.
3. A method as claimed in claim 1 or 2, wherein the method comprises the steps of: in the length setting mode, after the lower boundary position is determined, the upward key 3S is pressed for a long time, the automatic length setting mode is entered, and the controller moves upwards to find the locked-rotor position.
4. The method as claimed in claim 3, wherein the method comprises the steps of: when the offset is found accurately by one key, the remote controller is pressed for 5 seconds for a long time or pressed for 6 times for a short time, and then the automatic reset state is entered.
5. The method as claimed in claim 1, wherein the method comprises the steps of: and the length setting can also be realized by firstly detecting the position of the upper boundary, then automatically descending the curtain, pressing and stopping when the proper position of the lower boundary is reached, and pressing a downward key for 6 seconds for storing the position of the lower boundary, thereby determining the using length of the curtain.
6. The method as claimed in claim 1, wherein the method comprises the steps of: the controller comprises a key box and a radio frequency signal emitter which are connected with the single chip microcomputer through a lead, the radio frequency signal emitter is a remote controller, and the single chip microcomputer is connected with a radio frequency signal decoding unit.
7. A method as claimed in claim 1 or 6, wherein the method comprises the steps of: the safety length q is 5-50 mm.
8. The method as claimed in claim 1, wherein the method comprises the steps of: the high-precision metering chip is model number SSP 1837.
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| CN202010351936.4A CN111352291A (en) | 2020-04-28 | 2020-04-28 | Projection curtain control method with one-key alignment function |
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| CN202010351936.4A CN111352291A (en) | 2020-04-28 | 2020-04-28 | Projection curtain control method with one-key alignment function |
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| CN110209006A (en) * | 2019-06-27 | 2019-09-06 | 盐城天锐先锋电子科技有限公司 | A kind of projection screen limit control and limit control method |
| CN110286554A (en) * | 2019-06-27 | 2019-09-27 | 盐城天锐先锋电子科技有限公司 | A kind of projection screen limit method and position-limit mechanism |
| CN110286556A (en) * | 2019-08-01 | 2019-09-27 | 盐城天锐先锋电子科技有限公司 | A kind of curtain control method and control mechanism |
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2020
- 2020-04-28 CN CN202010351936.4A patent/CN111352291A/en active Pending
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104802617A (en) * | 2015-05-22 | 2015-07-29 | 上海加冷松芝汽车空调股份有限公司 | Control method for preventing rotation clogging and step loss of stepping motor |
| CN105140888A (en) * | 2015-08-11 | 2015-12-09 | 山东神戎电子股份有限公司 | Automation control method for preventing motor from excessive locked rotor |
| CN110209006A (en) * | 2019-06-27 | 2019-09-06 | 盐城天锐先锋电子科技有限公司 | A kind of projection screen limit control and limit control method |
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Application publication date: 20200630 |