Abstract: An articulated door system includes one or more door sections; a lifting block associated with a lower door section of the one or more door sections; a frame supporting the one or more door sections and engaging the lifting block; and a lead screw system including a rotatable lead screw that is configured to engage the lifting block and lift the lower door section up and down based on rotation of the lead screw.

Abstract: An articulated door system includes one or more door sections; a lifting block associated with a lower door section of the one or more door sections; a frame supporting the one or more door sections and engaging the lifting block; and a lead screw system including a rotatable lead screw that is configured to engage the lifting block and lift the lower door section up and down based on rotation of the lead screw.

Abstract: A shutter used, for example, as a sunshade has blades that are pivotally coupled to frame members of the shutter by respective pivot shafts that are split longitudinally into upper and lower halves. The pivot shaft halves can be adjusted radially with respect to one another to take up free movement that might otherwise allow the blades to vibrate when the shutter is in use.

Abstract: An expansion joint for a parking structure includes first and second rails for mounting on adjacent slabs at opposite sides of a gap therebetween and a cover plate that overlies the rails and covers the gap while permitting relative movement between the slabs. A series of turnbars are pivotally coupled to the underside of the cover plate using ball and socket joints so that lateral loads imposed on the cover plate are transmitted directly into the turnbars, minimizing the risk of shear failure between the cover plate and the turnbars. At the same time, the ball and socket joints allow the cover plate and turnbars to tip with respect to one another. The turnbars have spherical end portions that are received in complimentary channels in the respective rails so that the turnbars maintain the cover plate centered over the gap.

Abstract: An expansion joint for a parking structure includes first and second rails for mounting on adjacent slabs at opposite sides of a gap therebetween and a cover plate that overlies the rails and covers the gap while permitting relative movement between the slabs. A series of turnbars are pivotally coupled to the underside of the cover plate using ball and socket joints so that lateral loads imposed on the cover plate are transmitted directly into the turnbars, minimizing the risk of shear failure between the cover plate and the turnbars. At the same time, the ball and socket joints allow the cover plate and turnbars to tip with respect to one another. The turnbars have spherical end portions that are received in complimentary channels in the respective rails so that the turnbars maintain the cover plate centered over the gap.

Abstract: A pressure relief panel assembly for buildings in which explosions may occur includes a panel pivotally coupled to a frame for movement between a normal closed position and an open position and a calibrated magnet and striker set for holding the panel in its closed position. The magnet has a maximum holding force substantially in excess of a known force to which it is subjected at a predetermined blow-out pressure and a striker has secured thereto at least one non-magnetic shim defining a face for contact with the magnet. The shim thickness is selected to reduce the effective holding force exerted on the striker by the magnet, to the said known force.

Abstract: A panel laying machine for use as a "power assist" in installing access flooring. The machine includes a self-propelled chassis, a mast extending upwardly from the chassis and a jib turnably mounted on the mast. A panel gripper head is suspended from the mast by a cable coupled to a winch on the jib and the gripper head includes controls manually operable by an operator to raise and lower the panel, release the panel from the gripper head and move the chassis. A safety interlock is provided so that the panel cannot be released by the gripper head while the suspension cable is supporting a load above a predetermined limit.