| 摘要 |
In order to seal an internal space of a casing having an upper and lower casing members, a continuous groove with a semicircular cross-section is formed around a dust-and-water proof area of the lower casing member, and a continuous elongated protrusion is formed on the portion of the upper casing member corresponding to the groove, so that the protrusion is inserted in the groove when two casing members are engaged. Spherical sealing members each having the same diameter as the groove width are arrayed continuously in the groove without gaps therebetween. The width of the elongated protrusion is configured to be smaller than the groove width, so that the spherical sealing members compressed when the casing members are fitted are deformed to enter a space defined between the elongated protrusion and the groove, to thereby form a dust-and-water proof structure. Inserting the spherical sealing members in the groove is easy. |
