Constant velocity joint assembly integrated with wheel hub unit
A constant velocity joint assembly integrated with a wheel hub device may include an internal race coupled to an end portion of a driveshaft, a plurality of joint balls held in the internal race, and a hub housing accommodating and coupling the internal race holding the joint balls therein, with a bearing coupled to an external circumferential surface thereof, the hub housing provided as an external race of a constant velocity joint and the wheel hub device.
1. A constant velocity joint assembly integrated with a wheel hub device, the assembly comprising:
an internal race coupled to an end portion of a driveshaft;
a plurality of joint balls rotatably mounted in the internal race;
a hub housing accommodating and being coupled to the internal race holding the joint balls therein, wherein the hub housing includes a bearing mounted to an external circumferential surface of the hub housing, the hub housing provided to perform roles of both an external race and the wheel hub device, and wherein the bearing includes an internal ring, an external ring and bearing balls,
wherein a knuckle carrier is fixed to the external ring of the bearing,
wherein rows for supporting the bearing balls are accommodated on the hub housing and the internal ring of the hub bearing, respectively,
wherein the bearing balls are mounted onto the external ring and in the rows of the hub housing and the internal ring, and
wherein a lock nut is coupled to the hub housing and engaged to the internal ring to apply a preload to the internal ring,
a lock ring fixedly coupled to the hub housing while abutting against a side surface of the lock nut; and
a plurality of fasteners connected onto the lock nut through the lock ring.
2. The constant velocity joint assembly according to claim 1 , wherein the hub housing includes:
a circular hub portion to which the joint balls of the internal race are mounted, wherein the circular hub portion supports the internal ring; and
a housing portion supporting the external ring.
3. The constant velocity joint assembly according to claim 2 , wherein the bearing balls include:
an external ball and an internal ball provided on an external circumferential surface of the housing portion;
the internal ring supporting and holding the internal ball; and
the external ring slidably supporting the external ball and the internal ball.
4. The constant velocity joint assembly according to claim 3 , wherein the external ball is held by a ball support formed with the housing portion.
5. The constant velocity joint assembly according to claim 3 , wherein a hub cap is mounted to couple the circular hub portion and the internal race.
6. The constant velocity joint assembly according to claim 1 , wherein the hub housing is provided on an outer circumferential side with a first screw portion around which a plurality of key grooves is formed.
7. The constant velocity joint assembly according to claim 6 , wherein the lock nut has a second screw portion on an internal circumferential surface thereof, and a plurality of through-holes and wherein the lock nut is coupled around the hub housing using the first and second screw portions of the lock nut and the hub housing so that the internal ring of the bearing is applied with the preload by regulating a fastening force of the lock nut with the internal ring.
8. The constant velocity joint assembly according to claim 7 , wherein the lock ring includes a plurality of protrusions on an internal circumferential surface thereof, and a plurality of through-holes, and wherein the protrusions of the lock ring are fitted into the key grooves formed in the hub housing.
9. The constant velocity joint assembly according to claim 8 , wherein fasteners are configured to connect the lock nut and the lock ring into the through-holes of the lock nut and the through-holes of the lock ring.
10. The constant velocity joint assembly according to claim 1 , wherein the hub housing includes a circular hub portion having grooves into which the joint balls are inserted, the circular hub portion being disposed within a whole length (A) of the hub housing,
wherein at least the rows of the ball bearings, the lock nut, and a boot are disposed within the whole length (A) of the hub housing,
wherein a center of the internal race is disposed in the circular hub portion, and
wherein a correlation between the whole length (A) of the hub housing and a central length (B) of the internal race satisfies a condition of 1.25≤A/B≤1.4.
11. The constant velocity joint assembly according to claim 1 , wherein a correlation between a pitch circle diameter (C) of the bearing balls and a pitch circle diameter (D) of the joint balls satisfies a condition of 1.7≤C/D≤1.9.
12. The constant velocity joint assembly according to claim 1 , wherein a correlation between a pitch circle diameter (D) of the joint balls and a diameter (E) of the driveshaft satisfies a condition of 2.15≤D/E≤2.35.