Platen knob.

摘要

The invention relates to a platen knob (3) suitable for use in electronic apparatuses such as an impact dot printer. The knob (3) includes a first hollow cylinder (3g) having one bottom wall (3c), a second hollow cylinder (3a) extending from the interior surface of the bottom wall (3c) coaxially with the first cylinder (3g). The second cylinder (3a) is fitted on a shaft of a cylindrical platen (4) through a hollow boss (2a) of a casing (2) housing the platen (4). A cavity defined between the sidewalls (3b) of the cylinders (3a, 3g) receives a vibrationproof lining (112a) and/or an acoustical layer (113a). The lining (112a) suppresses a vibration of the platen knob (3). The acoustical layer (113a) seals the boss (2a) of the casing (2) and leaks no noise from the interior of the apparatus outside the casing (2). <IMAGE>