The sensor system of greenhouse wind speed monitor is simple in structure, good in reliability, strong in anti-interference ability, high in measurement accuracy, and easy to popularize and apply. When the sensor is exposed to wind, the tail rudder senses the direction of the wind, it quickly rotates the fuselage around the support shaft, and drives the code drum through the wind axis. Seven rectangular holes are processed on the code cylinder according to a specific rule. Seven groups of light-photosensitive tubes are installed inside and outside the code tube. Therefore, when the code cylinder rotates with the wind direction, seven sets of photoelectric devices are located The positions are different, and 72 groups of cyclic codes appear within 360°. The cyclic code directly reflects the variation of the wind direction in the range of 0-360° with a resolution of 5°.
The propeller on the front of the fuselage is used to feel the speed of the wind. The speed of the propeller is proportional to the speed of the wind. When the propeller rotates, it drives one end of the shaft with 8 tooth plates to rotate. Because the tooth plate has a fixed distance from the inductor coil, the 8 tooth plate rotates close to or away from the inductor coil and outputs a corresponding pulse signal. The size of the signal directly reflects The size of the wind speed.
The wind speed part is a proximity switch circuit which consists of an oscillator, a frequency discriminator, and a level shifter. When the 8-tooth plate is close to the inductor coil of the oscillator, the oscillation condition of the oscillator is destroyed and the oscillator is stopped. At this time, the discriminator has no voltage output, and the level converter output is “1â€. Conversely, when the 8-tooth plate is away from the inductor of the oscillator, the oscillator resumes oscillation. At this time, the discriminator has a voltage output and the level converter output is "0". The wind direction circuit is a photoelectric conversion circuit. Each photo-sensitive tube corresponds to a light-emitting diode. When light is present, 7 photo-sensitive tubes are all turned on. A code tube is installed between the output tube and the photo-sensitive tube. When the code tube rotates 360° Photosensitive tubes will generate 72 sets of cyclic codes. The wind direction and wind speed output signals are sent to the interface board for signal amplification, shaping, and level conversion processing. In order to facilitate the use of computers for data processing, the inverse code circuit is used to invert the code of the wind cycle code and output 72 binary codes. In order to protect the 8255 chip and block the outside world from interfering with the computer system, each bit of the wind direction binary code and the wind speed pulse signal are processed by opto-electronic coupling and anti-code circuits.
The application of wind direction wind speed monitor in smart greenhouses has promoted the development of modern equipment agriculture, improved the economic benefits of equipment agriculture, improved the product quality and output of greenhouse agricultural products, and contributed to the construction of rural economy.
Greenhouse planting is a very common device in modern agriculture, and it is also a rapid-growing equipment agriculture in recent years. During the greenhouse planting process, the internal temperature control is very important. Only by ensuring a suitable growth temperature can the growth of crops be promoted, but Temperature is affected by sunlight, outdoor temperature and humidity. Furthermore, in order to achieve maximum planting efficiency, natural ventilation should be used as much as possible when controlling the temperature. Therefore, in the process of greenhouse planting, the installation of wind direction wind speed monitor to detect the outdoor wind direction, wind speed plays an important role in the control of the temperature inside the greenhouse.