Horizontal articulated robot with bevel gears

A horizontal articulated robot with an arm which moves in the horizontal direction for use with objects to be transferred, comprising:

• a hand on which objects-to-be-transferred are to be mounted;
• said arm having at least two arm portions, comprising:
• a supported-arm portion to which said hand is rotatably joined to the front end thereof and a supporting-arm portion to which the base end of said supporting-arm portion is rotatably joined to the front end thereof;
• a main body portion to which the base end of said arm is rotatably joined;
• and
• a rotation mechanism structured to rotate said supported-arm portion with respect to said supporting-arm portion;
• wherein said rotation mechanism comprises:
• a motor which is arranged inside said supporting-arm portion or said supported-arm portion such that an axial direction of an output shaft of the motor coincides with a horizontal direction,
• a Harmonic Drive (registered trade mark) wave-motion gearing device which configures a joining portion as a joint section between said supporting-arm portion and said supported-arm portion and which is structured to reduce the power of said motor and transmits the result to said supporting-arm portion or said supported-arm portion,
• a first bevel gear which is coupled to said output shaft of said motor,
• and a second bevel gear which is coupled with a wave generator of said Harmonic Drive (registered trade mark) wave-motion gearing device and which meshes with said first bevel gear;
• wherein said second bevel gear is provided on an outer circumferential side of hollow shaft of the Harmonic Drive (registered trademark) wave-motion gearing device and on a lower side of a reduction gear of the Harmonic Drive (registered trademark) wave-motion gearing device;
• an outside diameter of the first bevel gear is smaller than an outside diameter of the second bevel gear;
• the outside diameter of the first bevel gear is smaller than an outside diameter of the motor;
• the second bevel gear is provided at an upper side of a shaft center of the output shaft of the motor;
• a lower end of the hollow shaft is provided to a lower side of the shaft center of the output shaft of the motor;
• and
• a predetermined wiring is provided on an inner circumference side of the hollow shaft.