COMPARATORS

DEFINITION

Comparator precision measuring instrument used for comparing the size of the component there upon of working standards. It works on the principle of relative measurements. Hence, it's also called an indirect sort of measurement, especially these are utilized in mass production where high precision is required on an outsized scale.

The following are the areas where the comparator is employed are discussed

• To check the newest purchase gauges and where inspection should be at a really fast rate, i.e., in mass production.
• In conjunction with some machine to scale back the damage of labour and to take care of tolerance limits at every stage of producing.
• Where components are graded into groups in selective assembly. The grades are divide consistent with the tolerance limits (ie., three or more groups)
• To set the corresponding work ( or) inspection gauges concerning laboratory standards.

The various types of comparators 

mechanical comparators 

• Dial indicator 
• Read type mechanical comparator 
• Johanson Mikrokator
• sigma comparator

optical comparators

• Zeiss ultra -optimeter
• Zeiss optotest  comparator 
• Newall OMS horizontal optimeter
• Eden-Rolt millionth comparator.

DIAL INDICATOR COMPARATOR

It consists of a rigid column for vertical adjustment and a little accurate reference plane or worktable for fine adjustment. it's simple and is right for checking components within a tolerance of +- 0.05 mm.

Each division on the dial of the dial indicator represents 0.02 mm movement of the plunger. With gauging device. Limit indexes, it is often used as a visible minimum tolerance limit, if the pointer records outside the limit indexes, the component is rejected. Otherwise, the component is well within the bounds. The inspection is often done effectively even by unskilled operators.