| 摘要 |
A rotary shaft includes: a first shaft member including a rail member and a first connecting member installed in an end of the rail member; and a second shaft member including a slider moveably installed on the rail member, a barrel-shaped object fixed to the slider, and a second connecting member installed on an end of the barrel-shaped object. The slider includes a slider main body and a plurality of roller-shaped rolling elements that are held in the slider main body. A plurality of roller-shaped rolling elements include: a first roller-shaped rolling element that rolls along a first rolling path and transfers torque between the slider and the rail member when a rotational force in a first direction is applied; and a second roller-shaped rolling element that rolls along a second rolling path and transfers the torque between the slider and the rail member when a rotational force in a second direction opposite to the first direction is applied. |
