PURPOSE: To permit mechanical connection of a cable and a conduit and permit connection of a fluid flow on a contact face of two rotatable members constituting a joint device therebetween.

CONSTITUTION: The connection of a fluid flow of a joint device for machine tool permitted between rotating members 1 and 4 is achieved by joining an annular channel 2 provided on an outer body 1 with a port 6 arranged on a hollow inner main body 4. A motor 8 fixed on the outer member 1 transmits an output to a drive shaft 9, which has a through hole 90, and the through hole 90 passes through a device constituted by the outer member 1 and the inner member 4.