The purpose of the present invention is to eliminate interference between an electric cable and surrounding components, damage to an interfering component, and breakage of the electric cable, and to reduce space for accommodating the electric cable. This robot arm mechanism has a base (101). A robot arm (102) having multiple rotary joint parts (J1-J4) is attached to the base (101). A stretchable cable (30) for supplying electric power and/or a signal to the tip part of the robot arm (102) is arranged inside the robot arm mechanism. The stretchable cable (30) is guided by means of cable guides (51). The cable guides (51) are arranged between a tip-side cable fixation part (133a) to a base-side fixation part (133b). A pathway extension part (40) for extending the wiring pathway formed by the cable guides (51) between the tip-side cable fixation part (133a) and the base-side fixation part (133b) is interposed on the wiring pathway of the stretchable cable (30).
Multijoint robot arm mechanism, ink jet printer, triaxial moving mechanism, hydraulic mechanism, and cable wiring mechanism