In 1858, American Ezra Warner obtained the invention patent for the corkscrew. This corkscrew looks like half bayonet, half scythe. When opening, just use a large, curved blade and press along the edge of the can to cut the can open. In 1870, American William Leeman invented a bottle opener with wheels that could open cans continuously and smoothly. However, his bottle opener must be adjusted to the size of the can. In 1925, a wheel corkscrew was born that improved on the shortcomings of the Liman corkscrew. This bottle opener uses serrated wheels to reduce slippage and can grip and spin along the rim of the can. Later, many improved bottle openers appeared on the market. To this day, the "looks" of bottle openers are still all kinds of strange, but they remain the same. The principle it is based on is still the principle of leverage.