It has jaws on both sides for external and internal measurements.This is made with only one scale on the front of the beam for direct reading.Types of vernier caliper are termed as type A, type B, and type C.
Vernier calipers are classified based on an international standard IS 3651-1974, according to this standard three types of vernier calipers have been specified to meet external and internal measurement requirements of up to 2000mm with the accuracy of 0.02, 0.05, and 0.1 mm. For taking a reading, we have to check how many main and sub marks an inch the bevel edge of the movable jaw has crossed and added the reading, the needle on the dial give. The rack remains on the main scale which is connected to the pinion of the dial.įor using it movable jaw is moved by the thumb roller. Like a dial test indicator, rack and pinion are used in it. Like vernier calipers, it can measure in inches as well as in milimeters. In place of the vernier scale, it contains a graduation dial as shown in the figure. For this purpose, nowadays Vernier Dial calipers are being used. In ordinary vernier caliper, there are chances of mistakes as far as clear reading is concerned. It should be used only for precision marking or measurement.It should be used on a surface plate only.While marking, excessive pressure should not be exerted on its scriber.It should always be used on the plain surface of the jobs.While using both types of vernier height gauges, it is necessary to keep in mind the following points: This type of vernier height gauges can be used as an ordinary vernier caliper by separating its base. All its parts have been shown in the figure.
This type of vernier height gauge is in the form of a set, which has a base vernier caliper, offset scriber fixing screw, etc. In Moveable base vernier, this facility exists. In this type of vernier height gauge there in no facility to set the beam or base according to the requirement of the job. In vernier Height gauge, the slide base remains joined with the beam permanently as shown. Off-set scriber is fitted on the beam itself with which height of a job is measured or marking is done. Beam reamains fitted on a base in lenght form. It is almost similar to vernier caliper but it is used by attaching some additional attachments. It is used for taking auccrate measurement of height of a job or for marking. Read also: Micrometer Screw Gauge and Types of Micrometers Parts of Vernier Caliper The principle of the vernier caliper is that when two scales or divisions slightly different in size are used, then the difference between them is used to increase the accuracy measurement. In 1631, French Pierre Vernier introduced a device to obtain accurate measurements required for scientific experiments. In ancient China, the caliper was born without the beginning of scale as the Qin Dynasty (AD 9). The word caliper means any instrument with two jaws which is used to determine the diameters of objects.
The main use of the vernier caliper is to measure the internal and external diameters of an object. There are three types of vernier caliper used in the physics laboratory to measure lengths of small objects accurately which could not have been possible with a metre scale. A vernier caliper is an instrument which is most commonly used for a variety of exact measurements, which was not necessarily related to the engineering manufacturer.
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