| 摘要 |
PURPOSE:To prevent the lowering in the abrasion resistance of a printing surface or/and high sped operability, by fixing a pin and a leaf spring by the welding due to a heat source with high energy density. CONSTITUTION:A pin and a leaf spring are constituted of a combination of various material qualities and welded by laser beam to assemble printing parts. As a result, a heat affected part due to welding is limited to an extremely small area range and the hardness of a printing surface and the strength of the leaf spring are allowed to coincide with respective functions thereof and the fatique destruction of the connected part can be set to the life of the printing surface due to printing quality or more. The effect of welding due to laser beam is shown by making it possible to lower the adsolute quantity of the quantity of charged heat by charging quantity of heat necessary for welding in a small range for a short time an, therefore, the same result is expected even by other heat source with high energy density such as electron beam welding. The hardness of a longitudinal cross section along three axes of the pin is slightly lowered (Hv=10) at the point spaced apart by 0.25 mm from a welding side end surface and it is cleared that other part receives no thermal effect at all. |
