Abstract: A door has a doorknob, and is hingedly mounted in a door frame having at least one vertical member. The door is capable of selective rotational movement between a closed configuration and an open configuration. The door has a first side and an opposed second side. The first side is oriented in a direction toward which the door opens. A barricade bar includes a flange member for selectively engaging the doorknob to prevent the separation of the flange member from the doorknob. The barricade bar also includes a frame member for coordinate engagement with the at least one vertical member. The frame member is rigidly coupled with the flange member. The barricade bar can be oriented adjacent the second side of the door so that the frame member engages the vertical member and the flange member engages the doorknob to prevent the opening of the door.

Abstract: A security bar for quickly barricading a doorknob-operated, outward-opening door from inside a room, especially useful for fire safety doors used in schools and similar institutions. The bar spans the doorway from the knob to at least one side of the doorframe, with the ends of the bar overlying, and preferably directly engaging, the sides of the doorframe in a non-rotating fashion. The bar has a doorknob-engaging platform that engages the inner doorknob. A clamping member carried by the doorknob-engaging platform normally rests in a storage position out of the way of the doorknob while the bar is being applied to the door, but is quickly activated to clamp the doorknob to the platform. A lock is optionally engaged to lock the clamping member in place and prevent attempts to lift the bar out of engagement with the doorknob. Attempts to force the door open from the outside simply force the bar more tightly against the doorframe.

Abstract: A security bar for quickly barricading a doorknob-operated, outward-opening door from inside a room, especially useful for fire safety doors used in schools and similar institutions. The bar spans the doorway from the knob to at least one side of the doorframe, with the ends of the bar overlying, and preferably directly engaging, the sides of the doorframe in a non-rotating fashion. The bar has a doorknob-engaging platform that engages the inner doorknob. A clamping member carried by the doorknob-engaging platform normally rests in a storage position out of the way of the doorknob while the bar is being applied to the door, but is quickly activated to clamp the doorknob to the platform. A lock is optionally engaged to lock the clamping member in place and prevent attempts to lift the bar out of engagement with the doorknob. Attempts to force the door open from the outside simply force the bar more tightly against the doorframe.

Abstract: A door has a doorknob, and is hingedly mounted in a door frame having at least one vertical member. The door is capable of selective rotational movement between a closed configuration and an open configuration. The door has a first side and an opposed second side. The first side is oriented in a direction toward which the door opens. A barricade bar includes a flange member for selectively engaging the doorknob to prevent the separation of the flange member from the doorknob. The barricade bar also includes a frame member for coordinate engagement with the at least one vertical member. The frame member is rigidly coupled with the flange member. The barricade bar can be oriented adjacent the second side of the door so that the frame member engages the vertical member and the flange member engages the doorknob to prevent the opening of the door.

Abstract: A machine is provided for assemblying the elements of a truss and fastening them together in a positive manner. A supporting table is made up of channel elements which have platforms thereon which are movable upwardly and are adjustable in a horizontal plane toward and away from the center of the table. A carriage runs upon spaced tracks to locate pressure plates which are mounted on a pair of like C-frames which are adjustable toward and away from each other so as to be effective for trusses of different heights. The pressure plates are moved toward each other and apply a substantial pressure for inserting a multiplicity of nails of a nail plate into the areas in which the members of the truss are to be secured together. This provides a truss of exact shape and dimension which is positively secured together and, where necessary, is provided with a rectangular opening in which a heating and/or cooling duct is supported.