| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the occurrence of a charge trip by contact of a discharge wire with a dust precipitation plate by disposing a detaining means for detaining the inclination of the discharge wire with respect to upper and lower bar materials in a section apart a specified distance from weld zones between these bar materials and the discharge wire. SOLUTION: The discharge wire 1 is joined to the upper round bar 4 by bending the discharge wire nearly perpendicularly near the weld zone 6 of its end to the upper round bar 4 to press this part to the outer periphery of the upper round bar 4 and applying spot welding in this contact part. At this time, a pawl 9 as the detaining means is formed in the section on the lower side in proximity to the weld zone 6 of the discharge wire 1, i.e., the side where a crack 7 can occur. This pawl 9 is disposed successively with the bent part of the discharge wire 1 and is so formed as to embrace the upper or lower round bar 4 from the outer side, by which the opening width B thereof is made smaller than the outside diameter D of the upper round bar 4. As a result, the inclination of the discharge wire 1 may be detained by the pawl 9 and, therefore, the occurrence of the charge trip may be prevented.</p> |
