Abstract: A door- or window sash which is pivotable relative to a door- or window frame between open and closed positions can be releasably affixed to the frame in the closed position in response to turning of a handle which can shift an elongated carrier relative to the frame between two spaced-apart end positions. The carrier supports a series of longitudinally spaced-apart projections each of which fully engages a complementary retainer on the sash during different stages of movement of the handle from one end position to the other end position. The arrangement may be such that the projection nearest to the handle is first to engage the complementary retainer on the sash, that the projection which is adjacent the nearest projection is next to engage the corresponding retainer, and so on. A safety device can be provided to releasably lock the carrier in the other end position.

Abstract: A casement window wherein the sash is pivotable in the frame about a vertical axis has a self-locking crank drive which pivots the sash between open and closed positions by way of a pivotable lever, a link which is coupled to the lever, and an actuator which is movably installed in the sash, which is coupled to the link and which forms part of a locking-unlocking mechanism for the sash. The first stage of rotation of the crank drive in order to pivot the sash from closed position involves a displacement of the actuator which ensures that the sash is unlocked, and further rotation of the crank drive results in pivoting of the sash to the open position. If the direction of rotation of the crank drive is reversed, the sash is moved to the closed position before the actuator is caused to lock the sash to the frame. A blocking device for the actuator is operated by the frame to release the actuator for movement to its operative position shortly before the sash reaches the closed position.