| 摘要 |
PURPOSE:To eliminate an extent of shifting displacement in the rotational direction and to stabilize an index signal producing position by arranging so that, upon termination of a metal hub positioning, a through-hole on a spindle hub driving shaft is contacted with one side of the driving shaft. CONSTITUTION:When positioning of a metal hub 1 is terminated by a revolting shaft 2 and a driving shaft 3, the spindle hub 4 having a through-hole 6 for the driving shaft designed to produce the prescribed index signal producing position is contacted with the driving shaft 3 at a point C and fixed in its position to eliminate the extent of shifting of a positioning hole 7 in the rotational direction. A free vertical movement is allowed due to a clearance B while the metal hub 1 is not positioned. |
