Wheel hub and wheel bearing assembly comprising the same

A wheel hub, comprising:

• an inner hub part made of a first material and comprising a central portion formed to protrude in an axially inward direction and a flange portion formed to extend in a radially outward direction from the central portion;
• and
• an outer hub part made of a second material, which is lower in strength and lighter in weight than the first material, and configured to be integrally coupled with the inner hub part,
• wherein the flange portion comprises a plurality of main extended portions in which a plurality of fastening holes are formed to penetrate in an axial direction while being arranged to be spaced apart from each other along a circumferential direction so that a wheel is mounted to the flange portion, the plurality of main extended portions being formed to extend along a plurality of virtual extension reference lines which respectively extend in the radially outward direction from a rotational axis toward positions of the plurality of fastening holes,
• wherein the outer hub part comprises a circumferential portion extending in the circumferential direction to connect the plurality of main extended portions,
• wherein each of the plurality of main extended portions has a first circumferential boundary and a second circumferential boundary with reference to the corresponding extension reference line,
• wherein the first circumferential boundary extends in a direction between a radially inward direction and a first circumferential direction, and the second circumferential boundary extends in a direction between the radially inward direction and a second circumferential direction,
• wherein the first circumferential boundary of each of the plurality of main extended portions extends in a direction closer to a vertical direction against the virtual extension reference line positioned adjacent to the first circumferential direction than an extension direction of the virtual extension reference line positioned adjacent to the second circumferential direction, and the second circumferential boundary of each of the plurality of main extended portions extends in a direction closer to a vertical direction against the virtual extension reference line positioned adjacent to the second circumferential direction than an extension direction of the virtual extension reference line positioned adjacent to the first circumferential direction,
• wherein the flange portion comprises a locking portion positioned at a portion where a radially outer end surface and an axially inner end surface of the flange portion are connected, and an axially inner end portion of the flange portion is more concave in the radially inward direction than an axially outer end portion of the flange portion, and
• wherein the outer hub part covers the locking portion and a radially outer portion of an axially outer surface of the flange portion.