How your gearbox functions

  1. Njnewland
    Ever wondered how your gun fires when you pull the trigger? It's not just plugging in a battery and your gun fires.

    Here is a guide explaining how your gearbox functions, what the parts in it are, and what they do.

    I will try to keep it simple and easy to understand.

    We will start with the battery. The battery is what powers your motor. The most common batteries used for Airsoft are nickel metal hydride (NIMH) and lithium polymer (lipo-ly) NIMH packs are built from 1.2v cells. Lipo-ly packs are made from 3.7v cells.

    Your battery has a discharge connector. The most common ones for Airsoft are tamiya (what comes with most AEGs stock) and deans/t-type.

    Your gun has a wiring system/harness. It has a connector to connect to your battery (usually deans or tamiya).

    The energy from your battery travels through the connectors and wiring system to the trigger contacts/assembly.

    The trigger assembly is on a trolley. Whenever you pull the trigger it completes the circuit from the battery. Without pulling the trigger your motor will have no power.

    After you pull the trigger, the power from the battery will go to the motor. The motor then spins the pinion gear.
    *your gun also has an Anti-reversal latch (ARL), it prevents your gears from spinning backwards.

    The pinion gear on the motor spins the bevel gear. The bevel gear spins the spur gear, the spur gear spins the sector gear.

    The sector gear pulls back the piston. At the same time, the tappett plate is being pulled back by a notch on the sector gear.
    The tappett plate is what holds your air-nozzle.
    The tappett plate always returns before your piston. The sector gear releases it before the piston.

    What makes it hard for your piston to go back is your spring. The stiffer the spring, the harder it is for the piston to go back.

    Your spring is held in place by a spring guide. It sits in place at the back of your gearbox.

    Your gun has 4 total gears. 1 on the motor, 3 inside the gearbox.

    Your gears are held in place by either bushings or bearings. Both do the same thing.

    Whenever your sector gear pulls the piston all the way back it will release it.

    On the end of the piston there is piston head. It gives you airseal so the air doesn't just leak out the sides or go nowhere.

    The piston and piston head travel through a cylinder. The cylinder holds all the air as it is being pushed by the the piston/piston head/spring.

    At the end of your cylinder there is a cylinder head. This is what your air from the spring and airseal parts exits from.

    There is an air-nozzle that is connected to your tappett plate. It moves back and forth with the tappett plate as it is connected to it.

    The air from the cylinder head goes into the air-nozzle. The air-nozzle goes into your hopup, shooting the BB.





    I hope this helped you better understand how your gun works!

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