To provide a static pressre journal bearing spindle having high rotating accuracy preventing transmission of the heat generated in a motor or the like to a rotating table on a side opposite to the motor through a spindle, preventing thermal expansion of the spindle, and further, and measurable by an electrostatic capacity type non-contact meter in a state of using a non-conductive material.
This static pressure journal bearing spindle includes: the spindle 2; an static pressure journal bearing 3 rotatably supporting the spindle 2; the motor 4 having a motor shaft 2c formed of an end of the spindle 2 and driving the spindle 2 to rotate; and a rotating table 5 fixed to the other end of the spindle 2. A spindle supported part 2a as a part of the spindle 2 rotatably supported by the static pressure journal bearing 3 and a spindle table side part 2b of the spindle 2 as a part on a rotating table 5 side than the spindle supported part 2a are respectively formed from a ceramics material, and a radial bearing part 3b of the spindle supported part 2a is plated with a conductive plate.
|WO/2004/017318||MOTOR HAVING A FLUID DYNAMIC BEARING WITH AN ASYMMETRIC SEAL|
|JP3762200||AIR TURBINE SPINDLE|
PIONEER ELECTRONIC CORP