The invention provides a slip ring device (10A) in which three ring members (11a) through (11c) are provided so as to be lined up in sequence along an axial line (Ax) of an input shaft (2) and brushes (12a to 12c) contact with the ring members (11a to 11c) respectively, three inner bus bars (15a to 15c) are provided and are supported by a sleeve portion (2b) of the input shaft (2), and contacting groove portions (17) are provided so as to dent in the radially outwards direction into the inner circumferential surfaces of the ring members (11a to 11c) and extend along the axial line (Ax) direction, with one end portions (16a to 16c) of the inner bus bars (15a to 15c) being set into these contacting groove portions 17 respectively.