Bearing device and supporting shaft for bearing device
The bearing devices includes a pair of opposed sidewalls, a supporting shaft which is inserted into shaft end insertion holes provided in the both opposed sidewalls, and a roller supported between the both opposed sidewalls by the supporting shaft. The supporting shaft includes a shaft main body that is made of a steel product subjected to a heating process and has a step shape in which the outer diameters of the both shaft ends are smaller than that of a middle portion and caps which is fitted to the both shaft ends and of which the end can be caulked. An end outer-diameter side edge of the cap is caulked to an inner-diameter side edge of the insertion hole.
1 . A bearing device comprising:
a bearing retaining member including a pair of opposed sidewalls and shaft-end insertion holes which are formed through the pair of opposed sidewalls so as to be coaxially with each other;
a supporting shaft passed through the shaft-end insertion holes, the supporting shaft including:
a shaft main body that is made of a steel product subjected to a heating process and includes a middle portion and a small-diameter end portion in which an end of the supporting shaft has a diameter smaller than that of the middle portion; and
a cap that is separated from the shaft main body, made of a material which has a hardness smaller than that of the shaft main body and fitted to the small-diameter end portion, and includes an end outer-diameter side edge which is caulked to the shaft-end insertion hole to be fixed to the opposite sidewalls; and
a roller supported by the middle portion through a plurality of roller elements.
2 . The bearing device according to claim 1 , an inner-diameter side of the end of the cap is caulked to an outer-diameter side edge of the small-diameter end portion.
3 . The bearing device according to claim 1 , wherein the bearing device is a rocker arm.
4 . The bearing device according to claim 1 , wherein the bearing device is a planet gear.
5 . The bearing device according to claim 1 , wherein the shaft main body is made of the steal material having a hardness of 650 Hv or more, ad the cap is made of the material having a hardness of 100 Hv to 400 Hv.
6 . The bearing device according to claim 1 , wherein the cap has an outer diameter substantially equal to an outer diameter of the middle portion of the shaft main body.
7 . A supporting shaft for a bearing device, the supporting shaft comprising:
a shaft main body that is made of a steel product subjected to a heating process and includes a middle portion and a small-diameter end portion in which an end of the supporting shaft has a diameter smaller than that of the middle portion; and
a cap that is separated from the shaft main body, made of a material which has a hardness smaller than that of the shaft main body and fitted to the small-diameter end portion, and includes an end outer-diameter side edge having a hardness which allows the end outer-diameter side edge to be caulked,
wherein the cap has an outer diameter substantially equal to an outer diameter of the middle portion of the shaft main body.
8 . The supporting shaft according to claim 7 , wherein the supporting shaft is a supporting shaft for a rocker arm.
9 . The supporting shaft according to claim 7 , wherein the supporting shaft is a supporting shaft for a planet gear.
10 . The supporting shaft according to claim 7 , wherein the shaft main body is made of the steal material having a hardness of 650 Hv or more, ad the cap is made of the material having a hardness of 100 Hv to 400 Hv.