| 摘要 |
PURPOSE:To largely reduce the noise of a platen roll by covering the inner periphery of a metal cylinder or any of the cylinder and the high hard rubber layer on the outer periphery of the cylinder with a lead layer. CONSTITUTION:A lead layer 5 has a damping function. For example, when the inner periphery of a metal cylinder 1 is covered with the layer 5, the layer 5 of the inner periphery is received by energy damping action due to the suitable flexibility and large surface density of the layer 5 when it is received by the vibration of the cylinder 1, thereby performing a preferable damping property. The damping effect is larger in the order of inner peripheral lead layer < outer peripheral lead layer < both inner and outer peripheral lead layers. If the weight of a platen roll is excessively large, it is inconvenient. Thus, the thickness of the lead layer is limited to its upper limit, and if the thickness is reduced, its soundproofing effect is decreased. In view of this, the range of the thickness of the lead layer is preferably approx. 0.3-1.0mm. |
