What is a comparator?

What is a comparator?

The dial gauge is an instrument for measuring lengths and shapes, using differential measurement (by comparison). The small movements of the palpation tip are mechanically amplified and transmitted to an indicator needle. It is a measuring instrument that is used for the verification of parts and that by its own means does not give a direct reading, but it is useful for comparing the differences that exist between various parts that are to be verified.Comparator

How does

Does comparator work?

The mechanism is to transform the linear movement of the contact slider into a circular movement described by the clock hand. Its construction consists of a stem that at one end has a rack that is connected to a train of gears that amplify the movement, finally to transmit it to a needle that is the visual part of the comparator.

Parts of a comparator

Being very intuitive and easy to use an instrument, there is no need to explain how each part works. I will only put an image with the parts that compose it.

Types of comparators

Among the types of comparators, we can find dial, digital, double-sided and vertical dial there are also instruments similar to comparator watches that are: Probe watches.


Probe The operation of a probe is basically the same as a comparator the only detail is that the probe can rotate and the other only works on the vertical axis.

reading comparator

How to read the comparator measurement

Reading a comparator is fairly straightforward. First, we have to know what the minimum value is between each division, then we have to see the lap counter and see how many turns the needle marks, each turn translates to 1mm, for example, 5 turns = 5mm, finally, we see that it marks the main needle to add it together with the turns it gave. Example In this example we can notice that the minimum value between divisions is 0.01, and the lap counter passed the number 5, we take that 5 and add the value indicated by the main needle.