Application
A camshaft is one of the most critical components in an engine valve system, which relates to the opening and closing of intake and exhaust valves. A part of the camshaft, known as the cam lobe, opens the inlet and outlet ports of the combustion chamber by pushing the intake and exhaust valves. There are two methods by which the camshaft can push the valves: One method is to push valves using a type of lever mechanism called rocker arms. The other method is to push cup-like devices called valve lifters. Whichever method is chosen, these parts and the cam lobe repeatedly slide against each other at very high speed when the camshaft is rotating. For this reason, cam lobes are required to have a high abrasion resistance.
In the machining process, surface roughness management is essential to reduce the friction between the cam lobe and the parts that slide against it as much as possible. The most common type of surface roughness measurement uses a contact-type surface roughness gage, but this probe-based measurement only allows you to acquire linear roughness data, limiting the overall inspection accuracy.
Olympus’ Solution Using the LEXT OLS5000 Microscope
Roughness measurements using the Olympus LEXT OLS5000 3D laser scanning microscope provide planar roughness data, which is more accurate than linear roughness data alone.
Product Benefits and Features
- Laser scanning measurement of planar roughness enables you to acquire more accurate data.
- When the surface roughness of a sample whose shape has an inclination like that of a camshaft is measured, it is important to accurately measure the roughness of the inclined surface by acquiring optically-correct data instead of digitally-corrected data. The LEXT OLS5000 microscope uses dedicated lenses that adapt to its 405 nm laser wavelength and eliminate aberration as much as possible. These lenses enable you to acquire correct data, even for an inclined area.
- In addition to roughness data, 3D and intensity images can be acquired, making the camshaft surface more easily recognized.
- Various kinds of data can be stitched together horizontally, enabling easy acquisition of extensive data. Using the pattern matching function and the position information of the stage’s critical dimension module, the LEXT OLS5000 microscope can provide stitching data that helps ensure measurement accuracy.
Images
A camshaft set on a LEXT OLS5000 microscope
Images of roughness measurements using a LEXT OLS5000 microscope
