A spindle device of a machine tool capable of stably injecting atomized cutting
fluid from the tip of a tool device 13 when a variation in fluidity of the
atomized cutting fluid occurs temporarily in atomized cutting fluid passages e1,
e2 or the supply of the atomized cutting fluid into the atomized cutting
fluid passage e1 is stopped and restarted, wherein the atomized cutting
fluid passages e1, e2 having a single passage cross section are formed
in the area ranging from the spindle 1 to the tip of the tool device 13
through the atomized cutting fluid passages e1, e2, and a vacant
chamber group transmission layer part 14 having a large number of vacant
chambers 142 stacked thereon in multiple stages or in the state of communicating
with each other and allowing the atomized cutting fluid to pass therethrough through
the groups of the vacant chambers 142 is formed in the atomized cutting
fluid passage e1 or e2.
