Drink beer every day, do you know how many teeth the beer bottle cap has?

Drink beer every day, do you know how many teeth the beer bottle cap has?
Why is beer designed with a sawtooth-shaped lid instead of a rotating one like other beverages? The answer is to “absolutely” prevent air from escaping. It is reported that at the end of the 19th century, William Painter (William Painter) of England invented the beer bottle cap. At that time, he worked hard to study how to prevent the carbon dioxide from running away, and the result was to add 21 serrated caps to the cap. Way. Many people must be thinking, why 21 serrations? Why not 15? Why not 20?
Drink beer every day, do you know how many teeth the beer crown cap has?
In fact, it is the principle of basic mechanics. When it comes to fixing objects, three-point fixing is the most stable compared to two-point fixing and four-point fixing. However, only three-point fixing cannot guarantee that the air will not be lost, so try to use 3 points. Multiples, the transformation of the sawtooth, after repeated experiments, the final result is that when there are 21 sawtooths, it is the most stable to fix the bottle mouth and prevent the air from escaping. If it is too little, it will not be firm. If it is too much, it will kill the bottle mouth and become unstable. 21 serrations are just right. In fact, there are still many brewers who want to break this tradition and have been researching beer caps, but no manufacturer can make beer bottle caps that are more stable than 21 serrations.