Security device for a dead bolt lock

A security device for a dead bolt lock, the dead bolt lock including a dead bolt and being mounted on a door having a given outline, the door itself being mounted in a doorframe provided with a door stop on which the door abuts when it is closed, an inner surface surrounding the door when the door is close, and an outer lateral surface disposed opposite the door stop with respect to the inner surface, the dead bolt being movable between an unlock position where it remains inside the outline of the door thereby allowing the door to open, and a lock position where the dead bolt juts out over the outline of the door and engages a cavity provided for that purpose in the inner surface of the doorframe, the security device comprising:

• a first rigid vertical plate for attachment to said doorframe and shaped to extend flat on the outer lateral surface of the doorframe opposite the door stop just in front of the cavity in the doorframe;
• a second rigid vertical plate integral to the first plate and shaped to extend flat on the inner surface of the doorframe, the second plate being provided with an opening for facing the cavity in the doorframe and for receiving the dead bolt;
• a rigid sleeve integral to the first and second plates, the sleeve being coaxial with the opening provided in the second plate and being adapted for extending in the cavity of the doorframe for receiving the dead bolt as it is in a lock position:
• a tightening means disposed inside the sleeve for keeping the dead bolt tight as it is in a lock position in the sleeve;
• a security lever mounted on said first plate and pivotable about a vertical axis adjacent to the first plate, the security lever including an inner arm on one side of the first plate for extending in the cavity of the doorframe for engagement with the dead bolt when the dead bolt is moved to the lock position thereby causing the lever to pivot around said vertical axis, the security lever further including an elongated outer arm integral with the inner arm and extending on another side of the first plate opposite said one side, the outer arm being shaped and sized for abutment on an outer surface of the door when the dead bolt has been moved to the lock position and has caused the lever to pivot around said vertical axis;
• first fastening means for securing the security device via the first plate to the doorframe;
• second fastening means for securing the security device to the doorframe via the second plate;
• wherein the first plate is provided with an opening on the inside of the sleeve, said vertical axis of the lever extending across the opening in the first plate;
• and
• wherein the tightening means comprise a spring-leaf mounted inside the sleeve and facing the opening in the first plate.