An unmanned vending machine is a machine that automatically pays for goods based on recognizing the coins put in. Vending machine is a common equipment for commercial automation, which is not limited by time and place, and can save labor and facilitate transactions. It is a brand-new form of commercial retailing, also known as a 24-hour business mini-supermarket. At present, the common domestic vending machine **** is divided into four kinds: beverage vending machine, food vending machine, comprehensive vending machine, cosmetics vending machine. The general vending machine money device consists of a coin slot, a selection device, a checking device to confirm the authenticity of the coin, a calculation device to calculate the amount of money and a money finding device.