Abstract: A pivot structure as part of a framework for temporarily suspending equipment such as a movie screen from a ceiling track can include an oblong beam adjustably mounted to the track. The pivot structure can include a housing having a cylindrical bearing for rotatively mounting a spindle. A pair of separately actuatable brakes can clamp the spindle in a locked position. Each brake can include a barrel having a concavity in its outer cylindrical surface which when driven against the spindle discourages its rotation.

Abstract: A barrier plate for supporting a cable within the internal channel of a ceiling mounted track having a pair of inwardly projecting parallel rails separated by a bottom slot. The barrier plate can be inserted completely into the internal channel and manipulated using a fingerhole through the plate to block downward movement of the cable through the slot. The plate can have radial disuniformities to frictionally bear against the pad of a user's finger to allow greater control of the plate orientation while engaged in the track channel.

Abstract: A pivot structure as part of a framework for temporarily suspending equipment such as a movie screen from a ceiling track can include an oblong beam adjustably mounted to the track. The pivot structure can include a housing having a cylindrical bearing for rotatively mounting a spindle. A pair of separately actuatable brakes can clamp the spindle in a locked position. Each brake can include a barrel having a concavity in its outer cylindrical surface which when driven against the spindle discourages its rotation.

Abstract: A joint structure as part of a framework for temporarily suspending equipment such as a movie screen from a ceiling track can include an oblong C-channeled beam adjustably mounted to the track. A first locking pivot mechanism can secure to a middle part of the beam by having an axially movable axle upon which a housing can rotate. A cam mechanism drives the axle axially between an unlocked and locked position where a collar on the housing pinches the track against a T-shaped head attached to the axle. A second locking pivot mechanism having a rotation axis mutually orthogonal to the first pivot mechanism can provide additional adjustability.

Abstract: A framework for temporarily suspending a movie screen from a ceiling track includes an oblong beam adjustably mounted to the track. A locking pivot mechanism secured to a middle part of the beam supports a pair of oppositely extending cantelevered booms. Each boom can have inwardly extending substantially parallel rails similar to a ceiling track. Each of the booms can carry variously sized locking cradles which can support a spar for a movie screen or other structures. A second locking pivot mechanism having a rotation axis mutually orthogonal to the first pivot mechanism can provide the booms with additional adjustability.

Abstract: A barrier plate for supporting a cable within the internal channel of a ceiling mounted track having a pair of inwardly projecting parallel rails separated by a bottom slot. The barrier plate can be inserted completely into the internal channel and manipulated using a fingerhole through the plate to block downward movement of the cable through the slot. The plate can have radial disuniformities to frictionally bear against the pad of a user's finger to allow greater control of the plate orientation while engaged in the track channel.

Abstract: A barrier plate for supporting a cable within the internal channel of a ceiling mounted track having a pair of inwardly projecting parallel rails separated by a bottom slot. The barrier plate can be inserted completely into the internal channel and manipulated using a fingerhole through the plate to block downward movement of the cable through the slot. The plate can have radial disuniformities to frictionally bear against the pad of a user's finger to allow greater control of the plate orientation while engaged in the track channel.

Abstract: A framework for temporarily suspending a movie screen from a ceiling track includes an oblong beam adjustably mounted to the track. A locking pivot mechanism secured to a middle part of the beam supports a pair of oppositely extending cantelevered booms. Each boom can have inwardly extending substantially parallel rails similar to a ceiling track. Each of the booms can carry variously sized locking cradles which can support a spar for a movie screen or other structures. A second locking pivot mechanism having a rotation axis mutually orthogonal to the first pivot mechanism can provide the booms with additional adjustability.

Abstract: A joint structure as part of a framework for temporarily suspending equipment such as a movie screen from a ceiling track can include an oblong C-channeled beam adjustably mounted to the track. A first locking pivot mechanism can secure to a middle part of the beam by having an axially movable axle upon which a housing can rotate. A cam mechanism drives the axle axially between an unlocked and locked position where a collar on the housing pinches the track against a T-shaped head attached to the axle. A second locking pivot mechanism having a rotation axis mutually orthogonal to the first pivot mechanism can provide additional adjustability.

Abstract: A barrier plate for supporting a cable within the internal channel of a ceiling mounted track having a pair of inwardly projecting parallel rails separated by a bottom slot. The barrier plate can be inserted completely into the internal channel and manipulated using a fingerhole through the plate to block downward movement of the cable through the slot. The plate can have radial disuniformities to frictionally bear against the pad of a user's finger to allow greater control of the plate orientation while engaged in the track channel.

Abstract: An assembly for improving closed door security comprises a door having a unitary first member comprising a first elongated flat plate portion lying substantially entirely in a first plane and a first elongated flat blade portion lying substantially entirely in a second plane, the planes being parallel with the end face of said door, the unitary member secured on the door with the blade portion spanning the latch bolt and extending parallel along the end face substantially entirely between the latch bolt and the outside door edge,a doorjamb having a unitary second member comprising a second elongated flat plate portion and having an opening exposing a latch bolt recess, and lying substantially entirely in a third plane and a second elongated flat blade portion lying substantially entirely in a fourth plane the third and fourth planes being substantially parallel with each other and with the first and said second planes, the second plate and second blade portions having an elongated slot therebetween,and wherei

Abstract: A door security assembly comprises first and second unitary members for being secured in a door and doorjamb frame, respectively, each member comprising a flat planar plate, a flat coplanar blade and a slot therebetween, with each blade received in the slot of the other member when the door is closed.