Abstract: An automotive wheel that can prevent deformation of a back side opening edge of a wheel rim in a radial direction and reduce the weight of the wheel rim is proposed. Because the automotive wheel has a structure in which an annular rib section formed in a stepped manner at each of the inside and the outside and having a thinner wall thickness than the other part of a ledge section is circumferentially formed in the ledge section of the wheel rim, an effect of preventing the deformation of a back side opening edge of the wheel rim in a radial direction is improved by virtue of a shaping effect of the annular rib section, and a weight reduction effect can be provided in connection with the thinner wall thickness of the annular rib section.

Abstract: In a roller support device, an inner peripheral surface of a bearing box is covered with a material having a poor wettability with respect to a molten metal, such as tantalum, graphite, C/C composite, silicon carbide or the like. The molten metal does not adhere to the covered portion, or even if the molten metal adheres to and is solidified on the covered portion, the molten metal can be peeled off with a light force. Therefore, after a support roller is pulled up from the molten metal, the molten metal does not prevent a rolling bearing from shifting in the axial direction thereof so that the roller support device can prevent an excessive force from being applied to the rolling bearing when the support roller, after it is thermally expanded once, is contracted as the temperature falls.

Abstract: A rolling bearing to be used in molten metal provides inner and outer races, a plurality of rolling elements and a cage, in which a solid lubricant is exposed at least in contact surfaces between the cage and the plurality of rolling elements, and further in which the solid lubricant is exposed also in contact surfaces between the cage and the inner and outer races. The cage is formed of a material having specific gravity of 0.8 to 1.2 with respect to the molten metal. In the rolling bearing, the wear resistance of the inner and outer races, the rolling elements and the cage can be improved.