Correct Answer - Option 3 : Mechanical comparator
Explanation:
A comparator does not give the dimension of the workpiece. In comparators, this difference is shown as magnified on the dial or the recording device.
Magnifications of 2000 times are quite common, and some may have as high as 40,000.
Comparators are classified as:
- Mechanical Comparators
- Electrical Comparator
- Optical Comparators
- Pneumatic Comparator
Mechanical comparator:
In this comparator, mechanical linkages are used for magnification. For magnification is Mechanical comparator, the following systems are used:
- Rack and pinion
- Cam and gear train
- Lever with toothed sector
- Compound levers
- Twisted strip
- Reeds combined with optical display
The basic advantages associated with mechanical comparators are that they are low in cost, do not require any power requirements like air or electricity, have a linear scale, are robust in design and so easily portable also.
- With electrical comparator, magnifications of the order of 40000 or higher are obtainable
- With a Pneumatic comparator, the magnification factor will vary from 1000 to 5000
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Optical comparators use both optical and mechanical means to get magnification.
