Patent ID: 8740626

Claim:
A rotational connector device comprising: a rotor; a stator forming an annular space between the rotor and the stator; a spacer rotatably arranged in the annular space; a single roller supported by the spacer; and a flat cable of which both sides are reeled outside of the annular space via the rotor and the stator, the flat cable being accommodated in the annular space in a state where a winding direction thereof is reversed in the middle by the roller, wherein the spacer comprises: an annular plate portion; a roller support portion provided on the annular plate portion; and a plurality of first guide portions provided on the annular plate portion, the roller support portion and the first guide portion respectively rising in the axial same direction on the annular plate portion, wherein the roller support portion rotatably supports the roller, the first guide portions are arranged to be spaced in the circumferential direction to sandwich the roller support portion therebetween on the annular plate portion, each first guide portion comprising an inner guide rib having a curved surface projecting inwards in an inner peripheral side of the annular plate portion and an outer guide rib having a curved surface projecting outwards in an outer peripheral side of the annular plate portion, and the annular plate portion is provided with a first lightening hole formed between the inner guide rib and the outer guide rib in each of the first guide portions, wherein, in the first guide portion, the inner guide rib and outer guide rib are connected by a single tension wall at each width center thereof.