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COMPARATORS AND ITS TYPES

Comparators are instruments which derive their name from the fact that they are used for simple and accurate comparison of parts as well as working gauges and instruments with standard precision gauge blocks. Sometimes they act as gauge themselves. Comparators are designed in several types to meet various conditions, but comparators of  every type incorporate some kind of magnifying device to magnify how much a dimension deviates, plus or minus, from an ideal. Most comparators indicate actual units of measurement, but some only indicate whether a dimension deviates within a given tolerance range. They also provide rapid means of inspecting very small articles made in large quantities. 

The comparators are classified according to the principles used for obtaining suitable degrees of magnification of the indicating device. The common Types are 

* Mechanical Comparators. 

* Electrical Comparators. 

* Optical comparators. 

* Pneumatic Comparators. 


mechanical comparator


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