Rotational connector device including a spacer disposed in an annular space formed between a rotor and a stator
A spacer arranged in an annular space between a rotor and a stator for supporting a roller reversing a winding direction of a flat cable is made of plastic having high lubricating properties. First guide portions on an annular plate portion are spaced by equal intervals from each other. The first guide portion includes an inner guide rib having a semicircle cross section projecting inward, an outer guide rib having a semicircle cross section projecting outward, and a tension wall connecting the inner guide rib and the outer guide rib. A second guide portion is provided between the first guide portions, and includes three parallel plate ribs extending from an inner peripheral side to an outer peripheral side of the annular plate portion, and circumferential connecting walls connecting the three parallel plate ribs.
1. 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.
2. A rotational connector device according to claim 1 , wherein
in the first guide portion, the inner guide rib and the outer guide rib are connected by a single tension wall.
3. A rotational connector device according to claim 1 , further comprising:
a second guide portion provided between the first guide portions along a circumferential direction of the annular plate portion, the second guide portion being provided with a plate rib extending from an inner peripheral side to an outer peripheral side of the annular plate portion, wherein
an inner end edge of the plate rib is positioned outwards by a predetermined amount from an internal contact circle concentric with the annular plate portion and touching each of the inner guide ribs of the first guide portions.
4. A rotational connector device according to claim 3 , wherein
the second guide portion includes a plurality of the plate ribs in the circumferential direction, and
the plurality of the plate ribs are connected by circumferential connecting walls.
5. A rotational connector device according to claim 3 , wherein
at least an inner end edge of the plate rib in the second guide portion is formed in a curved surface.
6. A rotational connector device according to claim 3 , wherein
the annular plate portion is provided with a second lightening hole formed in a predetermined range outward of the second guide portion and inward of an outer periphery of the annular plate portion.
7. A rotational connector device according to claim 1 , wherein
the spacer is made of plastic having high lubricating properties.