Mechanism

There are two main mechanisms in the Action Bank that allow it achieve its desired goal. The first is a gear coupled with a torsional spring and suction cup. When the arm is in the up position, the spring is close to its rest position. By pressing down on the cup, the spring is displaced and the suction cup makes contact with a stopper. Eventually, the force of the spring overcomes the vacuum force force of the suction cup, and the gear rapidly accelerates upwards. The clockwise motion of the arm, which is rigidly coupled to the gear, allows the coin to be thrown into the mouth of the bank.

The other main mechanism is a cam and follower system to lift the lid. The right has the same number of teeth as the gear on the left, and therefore spins at the same speed but opposite direction as the gear on the left. Therefore, as the arm is depressed, the right gear turns clockwise. The lever on the right gear acts as a cam and pushes a piece on the lid up and away. When the spring re-compresses, the right gear quickly turns counter-clockwise, and the lever pushes the lid up again, rotating it clockwise. The acceleration due to the cam-follower system is great enough to open the mouth wide, which allows the coin to enter into the main body of the bank.