| 摘要 |
The device has a main frame (10) with a groove (20) formed on inner surface of each of back wall (10b) and its side walls (10c). A pressing tongue (30) extends from the inner surface (10b') of the back wall such that it is parallel to upper wall (10a) of the main frame. The pressing tongue has a projection (30a) at its end. A screw (50) has a pointed end (64) which is rotatably provided in upper wall of the main frame. The screw has a knob (52) to which a cylindrical shank (60) is fixed. |
