Mechanical Comparators

Mechanical Comparators :

  • Mechanical comparators are extremely convenient to use
  • It does not require any external power for its operation
  • The measuring head consists of the work contact plunger(Stylus)
  • The movement due to size difference between standard and work piece operates a pointer
  • The pointer moves over a dial
  • This movement of the plunger is magnified by means of the gear train or levers
  • The magnification of mechanical comparators is limited to 1000
  • These are cheap and intended to measure external surfaces
  • However the mechanical devices are subjected to wear

Types of Mechanical Comparators


  • Dial indicator
  • Reed type mechanical comparator
  • The Sigma comparator

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