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Figure 1: Sine bar.
Sine bar is used for measurement of angle of given job or for setting an angle, sine bar is one of the famous instrument for angle measurement. It can be used in combination of slip gauge set and dial gauge for measurement of angle. It is as shown in Fig. 1, which consists of two rollers of same diameters fixed at a distance (L) between them, called as length of sine bar.
Spirit levels are used for checking and leveling the surfaces during installation and checking.
Figure 1: Spirit Level.
Figure 1: Micrometer.
Micrometer screw gauge works on the principle of nut and bolt. It consists of an accurate screw with about 10 or 20 threads per cm and revolves in a fixed nut. The rotation of thread is measured, which is already calibrated.
Figure 1: Parkinson’s Gear Tester.
Instead of measuring individual errors in gears, composite errors are checked. The composite error indicates the combination of errors in a gear. In Parkinson’s Gear Tester, the gear to be tested is rolled in mesh with a master gear and the errors will be indicated by dial gauge or recording unit.
Figure 1: Tool Maker’s Microscope.
Tool Maker’s Microscope is a direct reading measuring instrument used extensively in the shop for inspecting gauges, tools, screw threads, jigs, dies, and fixtures. The essential features of the microscope are shown in Fig. 1.
Figure 1: Gear Tooth Vernier Caliper.
The gear tooth thickness measuring vernier is as shown in Fig. 1. It measures the thickness of the tooth on pitch circle i.e. chordal thickness.
A dead weight tester is commonly used as a source of standard pressure for calibration purposes. It is basically a pressure producing and pressure measuring device.
A typical dead weight or piston gauge is schematically shown in the following figure 1,
Figure 1: Dead Weight Tester.
An inclined tube manometer is a cistern or well type manometer having an inclined column. It is also known as ‘draft gauge’. The schematic of an inclined tube manometer is shown in figure 1.
Figure 1: Inclined Tube Manometer.
