Definition and Parts of a Vernier Caliper

Vernier Caliper and Its Parts:

 Vernier Caliper

Vernier Caliper:

The vernier caliper is a measuring tool wont to get precise linear dimension measurements. A vernier micrometer is particularly useful to live the diameter of cylindrical objects as its jaws can clamp either side to urge accurate measurements.

Main Parts of a Vernier caliper: 

1. Upper Jaws or Inside Jaws 

2. Lower Jaws or Outside Jaws

3. Depth Rod 

4. Main Scale

5. Vernier Scale

6. Lock Screw

7. Thumb Screw

1. Upper Jaws or Inside Jaws:

The upper jaws are smaller in size and are attached to the upper portion of the vernier micrometer. Similar to the lower jaws, one of these jaws is fixed and the other is movable. The difference between them and the lower jaws is that the upper jaws are used for measuring inside dimensions of hollow objects such as inside diameters of pipes, lengths and widths of boxes etc. The jaws are placed inside the place to be measured and then opened till they touch the edges and the reading is taken at that point.

2. Lower Jaws or Outside Jaws:

The lower jaws are the most prominent feature of a vernier caliper. These jaws are designed to grip objects firmly between them for measurement. One of the jaws is fixed and attached to the main scale of the caliper while the other one is attached to the vernier scale and is movable. The lower jaws allow the vernier micrometer to live outer dimensions of objects like the length, width or diameter.

3. Depth Rod:

The depth rod is another useful feature of the vernier micrometer which may be wont to measure the depths of holes or steps. The depth rod may be a thin rod located at the top of the most scale. To measure with the depth rod, the sting of the most scale is placed on the highest surface of the opening then the jaws are opened. As the jaws are opened, the depth rod slides out with the most scale. The depth rod is extended till it touches rock bottom of the opening and therefore the reading is taken as was common.

4. Main Scale:

The main scale is that the large scale which runs along the body of the vernier micrometer. It is graduated either in centimetres and millimetres or inches depending on the type of units it is built for. In SI units rock bottom graduation of the most scale is generally 1mm. The main scale is stationary.

5. Vernier Scale:

The vernier is that the defining component of the caliper and what gives it its name. The vernier micrometer may be a smaller scale attached to the most scale and may move along the most scale because the jaws are opened or closed. The vernier provides accuracy to the reading of the most scale by further dividing rock bottom reading of the most scale into increments. In a metric caliper, the vernier is split into 50 increments each representing 0.02 mm.

6. Lock Screw:

The lock screw is used to fix the position of the jaws once the object is positioned properly so that readings can be taken without the fear of spoiling the position.

7. Thumb Screw:

The thumb screw is found at rock bottom of the vernier. Its purpose is to supply an edge for the user to slip the jaws easily and adjust the position of the jaws and depth rod while maintaining a firm grip on the object.