There are generally two kinds of Allen wrenches: Allen wrenches and external hexagon wrenches. The installation and disassembly of the external hexagon screw can be completed with an ordinary open-ended wrench or socket wrench, while the Allen wrench is specially used for vehicles, hexagon screws, machine wires and other mechanical equipment. The shape is generally L-shaped, and there are also divided ball heads and non-ball heads.
According to different structures, it can be divided into blunt wrenches, ring wrenches, dual-purpose wrenches, socket wrenches, hook wrenches, hexagon wrenches, torque wrenches and other special wrenches. Wrenches are usually made of carbon structural steel or alloy structural steel.
Extended data
The origin of Allen key must start with Allen key. In some non-English-speaking countries in Europe, people call "Allenkey" "Unbrakokey", which is actually the earliest brand of hexagon socket head screws. It was founded by American SPS Company around 19 1 1.
SPS Company imported an inner quadrangular screw from England earlier, but the price was very expensive. In order to save money, SPS decided to produce it by itself. H.T.Hallowell, the founder of SPS, said in his memoirs: "We started to try to make some square-hole screws similar to those in Britain, but soon found that such screws would not be accepted in the United States.
So I decided to add hexagonal holes to the screws. Hallowell's explanation of this history is vague, but later generations speculated that SPS was modified to avoid patent disputes of internal quadrangular screws.
In a word, SPS Company began to produce this new type of hexagon socket head screws and registered the trademark "Unbrako", which is taken from the homonym of "unbreakable", meaning "unbreakable". Later, hexagon socket head screws gradually replaced internal four-corner screws and became a new industry standard, which was widely used in automobile, airplane, machinery, furniture and other manufacturing industries.
Baidu encyclopedia-hexagon wrench
Baidu encyclopedia-hexagon wrench