| 摘要 |
PURPOSE:To obtain the wire dot head characterized by less abrasion between a guide hole and a printing wire and long life, by making the diameter of a part of each wire guide hole approximately equal to the diameter of the wire and making the diameter of at least one of entrances larger than the diameter of the wire. CONSTITUTION:The guide holes 15 and 15' are formed by wire guard bodies 11, 12, 11-1, and 12-1 so that the diameter of a part of each hole is approximately equal to the diameter (d) of the wire and the diameter of one of the entrances of the wire is larger than the diameter of the wire. Especially, it is desirable that relationship of R/t=2-25 is provided, where R is the radius of a curved surface shape provided at the guide hole, and (t) is the width. The material for the wire head, wherein 0-60wt% of graphite is added to epoxy resin, is suitable with respect to strength and abrasion resistance. |
