The French word crank came to our language as crank. French word that, in turn, emanates from Latin. Specifically, it comes from the word “manualis”, which can be translated as “manual”.
This is how it is called, according to the Royal Spanish Academy (RAE) in your dictionary, to a stork or a handle.
In the same way, we cannot ignore that other terms such as handlebar or grip, for example, are synonymous with crank.
A crank, therefore, is an element that certain machines have to manually confer a rotary movement. This means that the cranks are part of a mechanism that allows the transmission of movement.
In general, the crank is a metallic piece that has two branches: one is used as a handle to operate it and the other is fixed to one end of a shaft. Thus, by taking the crank by the handle and moving it, the axis movement is activated. If an axis is linked to several cranks, it is called crankshaft.
In addition to everything indicated, it is necessary to highlight another series of interesting data about the crank, such as the following:
-It is known that it was invented in the time before Christ.
-In Europe it began to become popular, especially in works related to water back in the 15th century.
-A crank is made up of three distinct parts: the connecting rod, the axle and the piston.
-There are two main types of cranks. On the one hand, there are the so-called foot-driven, such as those found in pedal sewing machines. On the other hand, there are those known as propulsion. Examples of the latter are the car window that is raised or lowered manually or a fishing reel.
-However, there are also other classifications of cranks. Thus, for example, there is also talk of rigid cranks, articulated cranks and even doubly articulated cranks.
-There are many devices that are equipped with a crank. Among the most common we can highlight from the mechanical jack that is used to change a wheel to the pedals of a bicycle through the system of raising and lowering an awning.
The cranks can transform a rectilinear movement into a circular movement or carry out the reverse process. The so-called crank-crank mechanism, for example, is key in internal combustion engines. In automobiles, the explosion of fuel produces the linear movement of the piston, which is transmitted to the connecting rod and turned into a circular motion in the crankshaft.
The first gramophones, meanwhile, they worked with a crank. These devices allowed to reproduce sound using a flat disk, which was placed on a turntable. A needle that traveled through the grooves of the record transmitted the vibrations to the pickup, which converted them into electrical impulses, which were finally amplified and projected. In the first machines of this type, a person had to turn a crank to rotate the plate on which the disc was located.