| 摘要 |
PURPOSE:To obtain the magnetic chuck device for a grinder whose displacement in the axial direction of a work attraction face accompanied by the temperature variation is extremely less, by making the chuck shaft center composed of the inner alloy of a low thermal expansion excellent in a magnetic characteristic. CONSTITUTION:Each machine part including a magnetic chuck device 1 is heated by the actuation of a grinder and a chuck shaft center 3 also rises in temperature mainly by current-flow. Owing to the shaft center 3 being composed of an inner alloy, however, the thermal expansion thereof is extremely less and the increase in the distance dimension L in the axial direction from the displacement in the axial direction of a work attraction face 5a, i.e., the center X in the axial direction of bearings 9, 9 up to the work attraction face 5a, is extremely less. The axial directional position of the work W supported by being attracted to the attraction face 5a receives no adverse effect by the thermal expansion in the axial direction of each machine part especially of the chuck shaft center 3. So a highly accurate grinding is executed, a finishing width dimension l in the axial direction with high accuracy is obtained, the stock removal is stabilized at all times as well and the reduction in the service life of a grinding wheel is also restrained. |
