How do vending machines detect counterfeit money?
Vending machines are a fairly old and common device in developed countries. You can find drinks, snacks, chips, and more in these machines. Looking at them, you'll probably wonder how they work? What happens when you insert money, and how do they accurately return the change?
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| (Photo: IT) |
Many people are curious about how a vending machine can distinguish between real and counterfeit money, or how it knows how much money has been inserted. Let's explore the mysteries inside these machines.
1. After inserting a coin into the machine, the metal block passes through a laser light to measure the coin's size. The vending machine can then detect the amount of money inserted.
2. In the next step of the test, the coin will be passed through an electromagnet to measure the metal composition inside. This will determine whether the coin is real or fake.
3. After identifying the coin, the machine will automatically sort it into its correct column. Counterfeit coins will be moved to the rejection slot.
4. If at this point the customer wants to cancel the purchase or return the change, the machine will automatically calculate and withdraw coins from the dispensers and return the change. This is why vending machines usually only accept certain denominations of currency.
5. If counterfeit money or the vending machine doesn't accept coins, they will be correctly aligned and returned to the customer outside. So what if your purchase gets stuck? An infrared sensor near the exit will check if any item has been dispensed. If not, the coin will be returned to you.
Watch the video below to better understand how vending machines work:
According to Daikynguyen
