A dial indicator or indicator head is a versatile tool for measuring various dimensions, often linear dimensions. In a dial indicator, the scale has a circular shape (dial shape); on the scale, the value of the measured quantity or part is read with an arrow showing (usually two arrows). Dial indicators are usually equipped with a gear train, which allows the pointer to make several revolutions in the measuring range. The measured ranges in dial indicators are completely different, it depends on the task and application of the indicator.
Usage
Indicators are used to measure linear dimensions, calculate the deviation of a part from given dimensions and parameters, or the relative position of surfaces. Often used to determine the deviation of various parts working on the machine. The dial indicator is a universal device; it can be used as an indicating device for an inside gauge, measuring clamp, indicator depth gauge, lever-type micrometer.
Indicators have found application in control and measuring operations in mechanical engineering for carrying out measurements of medium accuracy in the case when other measuring instruments do not provide the specified accuracy. It is used in production to control the accuracy of the installation of processed objects on technological equipment and to control the difference in size, shape and difference in the location of parts and assemblies.
Structure
On the front side of the dial indicator, there are two arrows on the dial, one large, the other small, and two scales, a large arrow 5 above the digitized circular scale 6 and a small arrow 3 above the reference (small) scale 10. The indicator dial (large arrow) has a division value of 0, 01 mm, and the reading scale (small arrow inside the indicator) scale is 1 mm. Moving the measuring rod 8 by 1 mm causes the large arrow 1 to rotate 100 divisions (one full turn), and the small arrow one division. The measurement range of such an indicator is 0 to 10 mm. The scale 6 of the indicator can rotate along with the rim when the scale is set to zero division and rotated relative to the large arrow 5.
Structurally, the dial indicator is similar to a watch, which is why such a name is a dial indicator or an indicator head with a vertical movement of the measuring tip 9. The basis of the dial indicator is its case, inside which a converting mechanism is built - a rail gear. A measuring rod 8 with a tip 9 passes through the structure of the indicator in the sleeve 7. The tips are of different shapes, needle-shaped, knife-like, etc., they can be unscrewed as needed. A rail is cut on the rod. The movements of the measuring rod-rail 8 are transmitted by gear wheels to the main arrow 5, the amount of rotation of which is counted on a round scale - by a dial. To set to "0", the dial is returned by a rim
Advantages
The main advantages of the dial indicator are versatility and ease of use with high measurement accuracy. At this time, p indicators with a digital indication of the measured value are becoming increasingly popular. The analog indication of dial indicators has the advantage that the instrument readings change smoothly in accordance with the change in the controlled parameter over time. This type of measurement is useful for dynamic measurements, for example, when you want to determine axial or radial runout.
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