With the progress of industrialization, the sawtooth number has changed from 24 to 2 1.
The reporter consulted Yi Yin, an associate professor at the School of Industry and Art Design of Nanjing University of Technology. Yi Yin told reporters that the initial sawtooth number of beer bottle caps was not 2 1, but there were 23 or 24 sawtooth bottle caps, and they applied for a patent.
As early as the end of 19, William Pate invented the 24-tooth bottle cap and applied for a patent. There is also a paper pad inside to prevent the beverage from contacting with metal, which is mainly based on Pater's finding that the number of teeth is the most suitable for sealing the wine bottle. As an industry standard, 24-tooth bottle caps were used until 1930s. With the process of industrialization, the original manual capping method has become industrial capping. The 24-tooth cap is first covered on the bottle one by one with a punch. After the automaton appears, put the bottle cap into the hose and install it automatically. However, in the process of use, it is found that the 24-tooth bottle cap is easy to block the hose of the automatic filling machine, and this will not happen if it is changed to 23 teeth. Finally, it was gradually standardized to 2 1 tooth today.
At present, the 2 1 tooth of beer bottle cap is manufactured according to the internationally accepted German standard DIN6099. This standard not only defines the diameter of the bottleneck, but also defines the edge shape and manufacturing material of the bottle cap. There are two main requirements for bottle caps: one is tightness, and the other is occlusion, which means that bottle caps should be firm. This means that the number of folds of each bottle cap is proportional to the contact area of the bottle mouth, and the wavy seal on the outside of the bottle cap can not only increase the friction, but also facilitate the opening of the bottle. 2 1 tooth is the best compromise between these two requirements. "