| 摘要 |
A ball transfer unit (12), comprising a body (13) in which a seat face (13b) recessed in a semispherical shape is formed, a plurality of small balls (14) rollingly in contact with the seat face (13b) of the body (13), a large ball (15) rollingly in contact with the plurality of small balls (14), and a cover (16) fitted to the body (13) to hold the large ball (15) and hold the small balls (14) between the large ball (15) and the scat face (13b) of the body (13). At least the body (13) and the large ball (15) are formed of either of PAI, PBI, PCTFE, PEEK, PEI, PI, PPS, melamine resin, aromatic polyamide resin, aluminium oxide, zirconium oxide, and silicon nitride. Thus, any foreign matter which gives damage to the surface of a transported material, induces defect in the transported material itself, or cannot be removed even by washing operation in a following process does not occur. |
