impossible to move the spray gun toward the axis of rotation 5 while maintaining the attitude of the gun as will be understood from fig1 these problems in the prior art wrist mechanism can be eliminated according to the embodiments of the invention which will be described below referring to fig1 there is shown an industrial robot generally designated 21 and shown as a robot for spray painting a swivel support 23 on a base 22 of the robot 21 is rotatable about a vertical first axis 24 while a lower arm 25 provided on the swivel support 23 is swingable to the left and right about a horizontal second axis 26 an upper arm 18 is vertically swingable about a horizontal third axis 27 at the free end of the lower arm 25 the upper arm 18 carries a wrist mechanism 17 on the distal end thereof a single flexible hose 28 for feeding a paint material for coating to a spray gun 20 is inserted into an opening 29 formed through the wrist mechanism 17 and then connected to the spray gun 20 the gun 20 is mounted to a wrist flange 19 of the wrist mechanism 17 the flange 19 is for mounting a work tool such as the spray gun 20 the flexible hose 28 is connected.