To provide an auto tensioner not containing hexavalent chromium and having a corrosive resistance equal to that of an auto tensioner in which a chromate film containing hexavalent chromium is formed on its friction plate retaining member.
This auto tensioner comprises a support member, a tension arm, a tension pulley, a torsion coil spring biasing the tension arm in a predetermined swing direction, and a frictional resistance imparting means imparting a frictional resistance to the tension arm in the swing direction. The frictional resistance imparting means comprises a friction plate disposed at the end face of the base end part of the tension arm and a friction plate retaining member 52 pressing the friction plate against the end face. A galvanizing film 6 is formed on the surface of the frictional plate retaining member 52. A corrosive resistant film 7 formed of a material expressed by an expression (xCr2O3-yMaOb-zH2O)(where M is a metal element) is formed on the galvanizing film 6.
| JPS5891244 | 【考案の名称】コンバインの刈取部における穀稈搬送装置 |
YANAI KUNIO
Einosuke Kishimoto
Akira Watanabe
Kiyosue Yasuko