Magnetically self-aligned multiball pitch artifact using geometrically simple features

• A magnetically self-aligned multiball pitch artifact is proposed.
• Simple-formed elements such as balls are aligned spontaneously by magnetic force.
• The high accuracy of the ball can be preserved and utilized effectively.
• The assembly of the artifact is easy and can be completed in 5 min.
• An experiment verified that the artifact is fundamentally valid for calibration.

The vibration/noise of gears is influenced by micrometer-order tooth pitch deviation, and therefore, advanced quality control is needed in the gear manufacturing process using measuring instrument. The accuracy of the pitch measuring instrument is verified using a master gear or artifact, but its accuracy is not sufficiently high, and its manufacturing is not easy. In our previous report, a novel high-precision pitch artifact composed of simple-shape parts (“multiball pitch artifact”) was proposed for the calibration of pitch measuring instruments. Simple-shape parts such as balls, cylinders, and planes can be manufactured with several-ten-nanometer-order accuracy. Therefore, this artifact can also have high accuracy. In this study, a magnetically self-aligned multiball pitch artifact is proposed in which the simple-shape parts are assembled with high precision using magnetic force without any special assembly technique. The artifact is designed and manufactured. A measurement experiment using a pitch measuring instrument is performed, and it is verified that the proposed pitch artifact is fundamentally valid for calibration.