Abstract: An anti-intrusion window is disclosed comprising a window frame assembly adapted to be attached to a building structure, first and second sash assemblies supported by the frame assembly and relatively movable with respect to each other, a position indicator supported by one sash, a sensor supported by the other sash and an alarm signal generator activated whenever the position indicator and the sensor are at least momentarily adjacent each other. Multiple windows are coupled to a second alarm signal generator which produces an audible alarm when the first alarm signal generator transmits an alarm signal. The sashes may be moved into cleaning positions without triggering an alarm.

Abstract: An anti-intrusion window is disclosed having a sash assembly which is movable along two paths; one for ventilating and one for cleaning the sash. A sensor is supported by one of the window frame or the sash assembly and a position indicator such as a magnet is supported by the other. The sensor detects the momentary presence of the position indicator to trigger an alarm. The sash assembly is movable through a range of ventilating positions without triggering the alarm while the alarm is armed. The sash may be moved into a cleaning position without triggering the alarm while the alarm is armed.