摘要 |
Printing pressure to be applied to a press roller (18) is obtained by a pressure applying spring (33) and an adjustable spring (41), and the adjustable spring (41) is extended or contracted by a tensile-force varying mechanism, thereby rendering the printing pressure variable. Accordingly, in cases such as where the viscosity of ink has changed due to a temperature change, and the contact time of a printing sheet (P) with respect to a rotary cylindrical drum (14) or a stencil sheet (M) has changed due to a change in the printing speed, it is possible to stabilize printed image performance by adjusting the density of an image which is printed. In addition, a strong tensile force for stabilizing the printing pressure by the press roller (18) is dispersed between the pressure applying spring (33) and the adjustable spring (41), and the adjustable spring (41) is extended or contracted.
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