| 摘要 |
PURPOSE:To enable surface grinding with high accuracy and speed, by providing pairs of oblique facets on an annular holder body whose peripheral surface has recesses in which grindstone segments are housed, and by fitting the grindstone segments on the oblique facets to firmly fix the segments in preset positions. CONSTITUTION:An annular holder 5 is provided with recesses 6 on the peripheral surface so that twelve grindstone segments 4 can be fitted in the recesses. Metal member 8 for holding the grindstone segments 4 down are fitted on protrusions 7 located alternately with the recesses 6. The angle alpha between a pair of oblique facets 6b in each recess 6 is equalized to that between both the mutually-equal side facets 9a, 9b of the grindstone segment 4 so that the facets 9a, 9b are tightly fitted on the oblique facets 6b. Each recess 6 is made divergent outwards so that the bisector of the angle alpha between the oblique facets 6b is coincident with the radius of the annular holder 5. Each metal member 8 has its central portion located on the protrusion 7 of the annular holder 5 and is secured thereon by two bolts so that the grindstone segment 4 fitted in the recess 6 is fixed on both the sides. |
