Abstract: A door alarm system and a door lock assembly having an interior rose having a request to exit (REX) switch. The alarm system generates an open door alarm when a door into a secured area is open unless the REX switch generates a REX signal indicating that the door was opened by someone on the inside of the secured area. Mechanical isolation in the door lock assembly prevents a forcing movement on the outside of the door from causing a false generation of the REX signal.
Abstract: A sort of tubular door lock whose inside knob or outside knob can be forced to rotate by each other's rotation and force a rotating unit to turn pushing and overpassing a projection of a knocking spring to get the knocking points at its both ends to knock on a bell for ringing. In addition, when said inside knob is locked up, the outside knob has no supporting force for making the latch rotated but can give an idle turning only.
Abstract: An improved knob lock commonly used, which comprises a bell inside. The main part of which is a rotator which is turned by rotating either of the knobs and has two extending-out springs to which are attached a steel ball respectively at their ends. Hindrance rods, which are used to prevent the springs from passing freely, make the springs bend until they are forced past the hindrance rods to knock hard on the bell giving out a ringing sound at the same time.