| 摘要 |
PURPOSE:To harden simultaneously and efficiently the tooth face and rear face of a rack bar for steering, by constituting a titled device of a pair of unit conductors which face to each other to said faces, a pair of the 1st and the 2nd contact electrodes, the 1st and the 2nd proximity conductors, and a high frequency electric power source. CONSTITUTION:A titled device is constituted of a pair of unit conductors which consist of the 1st conductors 2, 2' and the 2nd conductors 3, 3' combined via an electrical insulator 18 and face respectively to the tooth face side 10 and rear face side 11 of a rack bar 9 for steering, a pair of the 1st contact electrodes 4, 4' connected respectively to the 1st conductors 2, 2', and a pair of the 2nd contact electrodes 5, 5' connected respectively to the 2nd conductors 3, 3'. The 1st and the 2nd proximity conductors 6, 7 are connected respectively to the 2nd conductors 3, 3', and many injection holes for cooling water for hardening are punched on the surfaces thereof facing to the face 10 and the face 11. Inflow pipes 62, 72 for cooling water are welded to the respective holes. A high frequency power source 8 is connected to the 1st, and the 2nd conductors 2, 2', 3, 3'. |
