The purpose of the metal detector principle:
Example 1: if you want to detect whether there is a car passing on a road surface, because the car chassis is 0.5 meters or more from the road surface, plus cement will bury the depth of 5-10CM, therefore, buried in the ground diameter of 1 meter coil can be stable, accurate and reliable detection of whether there is a car on it, which is in highway traffic statistics, and so on. Parking area statistics are of great practical value.
The purpose of our metal detector principle:
Example 2: In each floor of the elevator controller, a sensor is required to detect whether the elevator has reached the stop position, if the mechanical stroke switch is used, there will be life and reliability factors; if the optocoupler is used, there will be long-term dust deposition failure; therefore, the best method is to install a metal detector determines whether a circuit is on or off according to the presence or absence of metal. This will be of great practical value in many devices and machines.
Game entertainment, safety inspection, search body metal products, including mobile phones, control knives, etc. According to the principle of this production, can also be designed according to the principle of this suite of car detection, flow statistics, elevator floor control, production equipment location detection, production equipment development and design, electronic product design. Planning, recreation equipment development, metal proximity switches, metal detection in the human body (there are many contraceptive rings made of metal, and some of the old Red Army soldiers may also have metal bullets in the body. In the future, there will be a lot of metal organs in the body of the situation), the mountain to find gold detection.
Power supply voltage: 3 to 5 V
Dimension: about 66*61mm/2.60*2.40in
Detection distance: about 50mm/1.97in
Debugging after welding:
The machine L1, L2 uses copper wire on the printed board to form inductance, without the need for everyone to make their own inductance, simple, high success rate! The circuit just uses more than 10 components, so long as the installation is correct, it can work normally. After installation, connect the power supply, adjust the potentiometer to just make no noise (not close to the metal), with the printed board antenna near the metal, it should sound at this time, away from the metal should stop the sound, if away from can not stop the sound, the potentiometer should be turned a little counter-clockwise and try again until it meets the requirements.
Long sound after power on, this is because the front oscillatory stage does not start vibration, there may be resistance, transistor and other components misplaced, or circuit boards in the coil between turns short circuit or open circuit, please use a magnifier to examine carefully. In addition, the Q2 magnification is too low to make Q3 turn off.
1*DIY metal detector assemblies (excluding plastic housing)
This set of positioning is an electronic teaching kit, mainly used to link welding and learning the working principle, can not really explore treasure, induction distance within 5 cm.
The following picture is a set of packages plus battery boxes.