Simple machine

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A simple machine is a tool that converts a force so that it can be used as effectively as possible to perform work . Examples of simple machines are the rope , the lever , the pulley and the inclined plane ( V ), which in any combination in almost any combustion engine occur.

In mechanical engineering , where machine stands for devices with a drive system, one speaks simply of device for the elementary and directly assembled simple machines.

Elementary simple machines

  • The rope and the rod move to the point where a force is applied.
  • The lever changes the starting point and size of a force.
  • The role shifts the point of application and the direction of the force.
  • The inclined plane and the wedge change the size and direction of a force.

Simple machines with combined modes of action

The following devices or device parts combine the mode of operation of elementary simple machines, as indicated below. Depending on the definition, they are also counted among the simple machines.

In some applications, gravity has a supporting effect ( scales ). Others are ergonomic , for example the pliers .

history

The use of simple machines can be proven in isolated cases in the animal kingdom. For example, some chimpanzees use sticks as levers to break up bees' nests (see Tool Use in Animals ).

Tools such as levers and wedges for lifting heavy masses, and rollers for moving were probably already used in the first Stone Age construction activities. In Egypt pulleys were used to e.g. B. erecting obelisks . The Romans also used them in their construction cranes. Simple machines also form the basis of the machine in today's sense. Elaborate work on combinations can be found in antiquity in the Mediterranean as well as in the Chinese. The construction of the great cathedrals of the Middle Ages would be without the use of mechanical equipment, such as lifting charge , Pulley, winches and treadwheels that of wind servants were served, not have been possible ( Crane ).

One of the first to systematically deal with simple machines was the Slovenian-Austrian mathematician Jurij Vega in the 18th century.

literature

  • Willy Schweiger: Fascinating mechanical engineering. Lecture notes, Chair for Construction Technology, Institute for Mechanical Engineering and Production Technology, Friedrich-Alexander University Erlangen-Nuremberg, 1998 ( web document ( Memento from January 15, 2005 in the Internet Archive ), pdf)

Individual evidence

  1. ↑ Thomas Krist: Formulas and Tables Basic Knowledge of Technology, Data and Terms for Technicians , Sect./Tab. AT 6
  2. ↑ cf. Thomas Krist: Formulas and tables Basic knowledge of technology: Data and terms for technicians and engineers. Springer-Verlag, 2013, section Simple machines: principles and formulas , sheet AM / 6 2.21 12-7 ff ( limited preview in the Google book search).
  3. ^ Albert Neuburger: Technology of antiquity . Reprint-Verlag Leipzig, Holzminden 1996, ISBN 978-3-8262-1400-4 (unchanged reprint of the original edition, Leipzig, Voigtländer, from 1919).
  4. ^ Joseph Needham , Wang Ling: Science and Civilization in China . Ed .: The Needham Research Institute. VOL. IV. Physics and Physical Technology. Pt. 2. Mechanical engineering . Cambridge University Press, Cambridge 1965 (English).