Small souvenir safe

This safe can hold a can of coffee, a box of chocolates or nuts, a piggy bank with coins, and similar items. The safe is equipped with an electric combination lock made from a seven-segment display. The lock latch is driven in a completely unconventional way – by a tiny micromotor typically used to create vibrations in phones. Since this micromotor can operate from a single 18650 lithium-ion battery, I was able to greatly simplify the entire electrical circuit. The entire electrical component consists of the battery, micromotor, 8 microswitches, and wires with connectors. I solved the problem of matching the high-speed but low-power micromotor with the slow-moving lock latch by using a flywheel made from a 20 mm diameter rubber wheel from a children's toy car. When the correct code is entered, the lock opens in two stages. First, lift the lever containing the micromotor up to activate the microswitch, which will connect the entire circuit. Wait a few seconds for the flywheel to spin. Then quickly but carefully lower the lever down. This will turn off the motor and cause the flywheel to contact the latch, extending it by inertia. At this point, rotate the two halves of the safe to open it. The combination lock is a standard series-connected microswitch. With seven switches, there are 128 combinations. All microswitches have a blue wire soldered to the NC contact, a violet wire to the NO contact, and a wire of a different color to the C contact. This makes it easier to change the code when needed. An example circuit diagram for code "4" is shown in the photo. In addition to an 18650 battery and a micromotor, to build the safe, you will need long M8 bolts and metal tubes (the length depends on the height of the item being stored), 4-6 M8 nuts, and washers. An M6 bolt or stud, 177 mm long, 9 M6 nuts, and 3-5 washers. The microswitches are pictured; their springs may need to be bent. Copper wire for securing the microswitches, 2 mm in diameter. Copper wire for securing the latch and motor lever, 1.5 mm in diameter. The battery contacts need to be made from flexible, conductive metal. The wires and connectors are from the Arduino kit. You'll also need to make springs for the micromotor lever and a softer spring for the latch. The seven-segment digits are from another project of mine https://www.thingiverse.com/thing:7372779 Video https://youtu.be/vK4tY90DTn0

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