A control method of a stormproof billboard,
- wherein said stormproof billboard comprises:
- a column, wherein a pedestal is disposed on a top of said column;
- a billboard frame, wherein a rotating table is fixed on said billboard frame and corresponding to said pedestal;
- a rotating element disposed between said rotating table and said pedestal so as to make said rotating table rotate with respect to said pedestal;
- a motor disposed on said column, wherein a driver gear is driven by said motor to rotate said rotating table;
- an electromagnetic brake disposed on said column to lock said rotating table;
- an anemometer for measuring a wind speed;
- a trigger switch disposed between said rotating table and said pedestal to measure that whether said rotating table aligns with said pedestal;
- and
- an electric control assembly respectively connecting with said electromagnetic brake, said motor, said anemometer and said trigger switch, wherein said electric control assembly controls working of said motor and said electromagnetic brake by a signal of said trigger switch and a wind speed signal measured by said anemometer,
- comprising the steps of:
- (11) predetermining a first secure wind speed, a second secure wind speed which is less than the first secure wind speed, and a delay time;
- (12) beginning to collect a first wind speed measured by said anemometer with said electric control assembly;
- (13) judging whether the first wind speed is greater than or equal to the first secure wind speed, if not, returning to the step (12);
- if yes, said electric control assembly sends a control signal to turn on said electromagnetic brake, such that said electromagnetic brake gets power and releases said rotating table so as to make said billboard frame rotate with the natural wind, then entering the next step;
- (14) beginning to collect a second wind speed measured by said anemometer with said electric control assembly;
- (15) judging whether the second wind speed is greater than or equal to the first secure wind speed, if yes, returning to the step (14);
- if not, entering the next step;
- (16) judging whether the second wind speed is less than the second secure wind speed, if not, returning to the step (14);
- if yes, turning on an inner timer which has been predetermined with the delay time, then entering the next step;
- (17) beginning to collect a third wind speed measured by said anemometer with said electric control assembly;
- (18) judging whether the third wind speed is less than the second secure wind speed, if not, returning to the step (14);
- if yes, judging whether the timer has expired, if not, returning to the step (17), if yes, entering the next step;
- and
- (19) judging whether said electric control assembly has received the control signal from said trigger switch, wherein said trigger switch sends the control signal to said electric control assembly when said rotating table has aligned with said pedestal, if not, said electric control assembly continues sending the control signal to turn on said electromagnetic brake and said motor, such that said electromagnetic brake continues to release said rotating table so as to make said billboard frame reset by the drive of said motor;
- if yes, said electric control assembly sends the control signal to make said electromagnetic brake and said motor lose power so as to make said electromagnetic brake lock said billboard frame, returning to the step (12).