| 摘要 |
PROBLEM TO BE SOLVED: To provide a sheath heater capable of attaching a resistance wire coil to a sheath tube without tilting it. SOLUTION: The sheath heater 2 includes the sheath tube 5 formed of cylindrical metal extending in an axial direction and having an attaching hole 4 at a tip 5a and an opened rear end, a columnar energization terminal having a tip inserted into a rear end side of the sheath tube 5, the resistance wire coil 7 provided in the sheath tube 5 and having a tip 7a and a rear end connected to the energization terminal, and a plug member 10 having a plug body 11 blocking the attaching hole 4 and a welding seat 12 welded to the tip 7a of the resistance wire coil 7. The welding seat 12 of the plug member 10 has a semi-spherical shape. In the sheath heater 2, since the tip 7a of the resistance wire coil 7 and a semi-spherical face of the welding seat 12 constitute a pair similar to a ball joint, the resistance wire coil 7 can be welded to the plug member 10 without causing a substantial inclination. COPYRIGHT: (C)2010,JPO&INPIT |
