Special Types
Switches can be designed to respond to any type of mechanical stimulus: for example, vibration (the trembler switch), tilt, air pressure, fluid level (a float switch), the turning of a key (key switch), linear or rotary movement (a limit switch or microswitch), or presence of a magnetic field (the reed switch). Many switches are operated automatically by changes in some environmental condition or by motion of machinery. A limit switch is used, for example, in machine tools to interlock operation with the proper position of tools. In heating or cooling systems a sail switch ensures that air flow is adequate in a duct. Pressure switches respond to fluid pressure.
Read more about this topic: Switch
Famous quotes containing the words special and/or types:
“Myths, as compared with folk tales, are usually in a special category of seriousness: they are believed to have “really happened,” or to have some exceptional significance in explaining certain features of life, such as ritual. Again, whereas folk tales simply interchange motifs and develop variants, myths show an odd tendency to stick together and build up bigger structures. We have creation myths, fall and flood myths, metamorphose and dying-god myths.”
—Northrop Frye (1912–1991)
“The bourgeoisie loves so-called “positive” types and novels with happy endings since they lull one into thinking that it is fine to simultaneously acquire capital and maintain one’s innocence, to be a beast and still be happy.”
—Anton Pavlovich Chekhov (1860–1904)