Tip and pivot window misuse preventer

摘要

Two levers (10,20) pivoted on a common axis (5) are spring-loaded (11,12) so as to pivot by different angles in opening or tipping settings away from the window drive rail. In window closure, a lever engages a main pin (30) on the fixed frame and thus applies a lifting force to the window (1) as the lever swings back. The lever only works against its spring after the first lever in closure, and thus frees an off-round locking bolt reaching through the drive rail (2), moving this bolt along in a shaped lever recess. The lever is tripped indirectly by an intermediate pin on the lever so that once lever has swung through its idle angle and just before closure, the lever pin engages lever thus swinging this shut so as to free the bolt in the closure position.