| 摘要 |
PURPOSE:To secure sufficient airtightness and to obtain stable rotary torque, by compositely molding an elastic seal member from a plurality of elastic rubber materials different in hardness and constituting the cross-sectional structure from two or more rubber layers different in hardness. CONSTITUTION:An elastic seal member 109 consists of an upper half comprising a soft rubber member 201 and a lower half comprising a hard rubber member 202 and the boundary surfaces of soft rubber and hard rubber are bonded with sufficient strength by composite molding. Therefore, the partial thinning of the elastic seal member having been easy to generate in conventional technique, in such a state that a rotating bezel rotated, can be prevented by enhancing the hardness of the hard rubber member 202 and sufficiently securing the rigidity of the elastic seal member in the peripheral direction thereof and the lowering in airtightness is prevented even in such a state that the rotating bezel is rotating. Further, stable rotary torque can be obtained by sufficiently lowering the hardness of the upper soft rubber member 201 and securing a clamping flange corresponding to the lowering in hardness. |
