Principle of supermarket security door

1. The principle of the safety door is that the crystal oscillator generates a sine oscillation of 3.5-4.95M, which is divided into a sine wave of about 7.6K by the frequency divider. After being amplified by triode and coil power, the large coil input to the door panel (area 7) emits electromagnetic waves, which are received by the coils in the door area 1-6 respectively.

2. After receiving, compare the received signal with the reference signal. After the change is found, the output level of the acquisition card is changed, and the CPU scans the data of the acquisition card in six positions within 280 milliseconds to determine the position of the metal and output the display.

3. The structure of the safety door includes door panel structure safety door and chassis structure safety door.

4. The workflow of security door detection is: CPU detection → one group of infrared rays is blocked → detecting whether the data of each acquisition card changes → alarming → detecting another group of infrared rays → resetting and re-detecting.

Extended data:

Precautions for emergency doors:

1. Except for the all-rain-proof security door, no other security door can get wet in the rain, and it must be covered with a sunshade when used in the open air.

2. There must be no large metal objects such as iron gates, elevators and iron columns around the security door 1 meter.

3, security door installation must be fixed firmly, to avoid strong wind or collision caused by the door body shaking.

4. Stay away from objects that can generate magnetic fields, such as distribution boxes and electrical equipment.

Maintenance method of security door:

1. The stains on the door surface can be wiped with a damp cloth.

2. Oils and stains that are difficult to clean can be wiped with Tianna water, alcohol and trowel water.

3, need to shut down for more than 2 hours every day, to prevent overheating and reduce the performance of long-term working parts.

Reference source Baidu encyclopedia-security door