| 摘要 |
A link arm assembly, for a window sash rotatable in opposite support arms 23 about a central pivot axis 24 through an angle of from 0 to 180 degrees, includes first and second link arms 18, 20 pivotably supported by a common member 15. The movement of the assembly is restricted by locking means comprising a locking member 26 connected with one of the link arms and with either the support arm or the common member 15. The locking member 26 includes one of a guide pin and groove (27, 28 fig 2). The guide pin is permanently located within the groove, which has an arresting section 29 disposed between its opposite ends 28a, 28b. <IMAGE> |
