Ball circulating groove structure of ball nut

1. A ball circulating groove structure of a ball nut structured such that a deflector is molded by resin in a hole penetrating from an inner surface to an outer surface of a ball nut, adjacent spiral grooves of the ball nut are connected by an S-shaped return groove of the deflector, and a ball rolling along a spiral groove of a thread shaft is guided along a peak portion formed between the adjacent spiral grooves of the thread shaft by the return groove of the deflector so as to be returned to the adjacent spiral groove of the thread shaft while getting over the peak portion and circulate,

wherein the deflector is provided with an inner collar extending in a penetrating direction of the hole of the ball nut and contacting the ball nut on the inner surface of the ball nut, and an outer collar contacting the ball nut on the outer surface of the ball nut; and

the inner collar is engaged with an inner engagement surface provided in a concave manner on the inner surface of the ball nut, and the outer collar is engaged with an outer engagement surface provided between a side engagement surface and the hole.

2. A ball circulating groove structure of a ball nut structured such that a deflector is molded by resin in a hole penetrating from an inner surface to an outer surface of a ball nut, adjacent spiral grooves of the ball nut are connected by an S-shaped return groove of the deflector, and a ball rolling along a spiral groove of a thread shaft is guided along a peak portion formed between the adjacent spiral grooves of the thread shaft by the return groove of the deflector so as to be returned to the adjacent spiral groove of the thread shaft while getting over the peak portion and circulate,

wherein the deflector is provided with an inner collar extending in a penetrating direction of the hole of the ball nut and contacting the ball nut on the inner surface of the ball nut, and an outer collar contacting the ball nut on the outer surface of the ball nut;

wherein the outer collar extended in the penetrating direction contacts the ball nut along side engagement surfaces of the ball nut separate from the hole; and

wherein the inner collar is engaged with an inner engagement surface provided in a concave manner on the inner surface of the ball nut, and the outer collar is engaged with an outer engagement surface provided between the side engagement surfaces and the hole.

3. A ball circulating groove structure of a ball structured such that a deflector is molded by resin in a hole penetrating from an inner surface to an outer surface of a ball nut, adjacent spiral grooves of the ball nut are connected by an S-shaped return groove of the deflector, and a ball rolling along a spiral groove of a thread shaft is guided along a peak portion formed between the adjacent spiral grooves of the thread shaft by the return groove of the deflector so as to be returned to the adjacent spiral groove of the thread shaft while getting over the peak portion and circulate,

wherein the deflector is provided with an inner collar extending in a penetrating direction of the hole of the ball nut and contacting the ball nut on the inner surface of the ball nut, and an outer collar contacting the ball nut on the outer surface of the ball nut;

wherein the ball nut has holes at three positions spaced at 120 degrees in a circumferential direction, and the deflector is provided in each of the holes; and

wherein the inner collar is engaged with an inner engagement surface provided in a concave manner on the inner surface of the ball nut, and the outer collar is engaged with an outer engagement surface provided between a side engagement surface and the hole.

4. A ball circulating groove structure of a ball nut as claimed in claim 2 , wherein the ball nut has holes at three positions spaced at 120 degrees in a circumferential direction, and the deflector is provided in each of the holes.

5. A ball circulating groove structure of a ball nut structured such that a deflector is molded by resin in a hole penetrating from an inner surface to an outer surface of a ball nut, adjacent spiral grooves of the ball nut are connected by an S-shaped return groove of the deflector, and a ball rolling along a spiral groove of a thread shaft is guided along a peak portion formed between the adjacent spiral grooves of the thread shaft by the return groove of the deflector so as to be returned to the adjacent spiral groove of the thread shaft while getting over the peak portion and circulate,

wherein the deflector is provided with an inner collar extending in a penetrating direction of the hole of the ball nut and contacting the ball nut on the inner surface of the ball nut, and an outer collar contacting the ball nut on the outer surface of the ball nut;

wherein the outer collar protrudes to both sides of the deflector extending along the axial direction of the ball nut, in an outer surface side of the deflector which is flush with the outer surface of the ball nut; and

wherein the inner collar is engaged with an inner engagement surface provided in a concave manner on the inner surface of the ball nut, and the outer collar is engaged with an outer engagement surface provided between a side engagement surface and the hole.

6. A ball circulating groove structure of a ball nut as claimed in claim 2 , wherein the outer collar protrudes to both sides of the deflector extending along the axial direction of the ball nut, in an outer surface side of the deflector which is flush with the outer surface of the ball nut.