Abstract: A bifold door includes an upper panel including a top edge disposed proximate an anchor and a lower edge disposed distal of the anchor. The upper hinge, connecting the anchor to the top edge, permits rotation of the top edge of the upper panel but prevents elevation of the top edge of the upper panel. A first actuator, connected to the anchor and the upper panel, lifts the lower edge of the upper panel upwardly and outwardly, and effects lifting of the upper panel. A lower panel, separated from the upper panel, includes an upper edge disposed proximate the lower edge and a bottom edge disposed distal of the lower edge. A second actuator, connected to the upper panel and to the lower panel, lifts the upper edge of the lower panel upwardly and outwardly, and to effect lifting of the lower panel.

Abstract: A device. The device includes a shaft having a longitudinal axis, a first end, and a second end. The device also includes a connector attached to the first end of the shaft. The device also includes a rod connected to the shaft. The rod comprises a third end and a fourth end. The third end is connected to the second end of the shaft. The rod is about parallel to the longitudinal axis. The device also includes a spring surrounding the rod. The spring is compressible or extendable along the longitudinal axis. The device also includes a stop connected to the rod at a position distal to the spring. The stop resists longitudinal compression or extension of the spring.

Abstract: A device. The device includes a shaft having a longitudinal axis, a first end, and a second end. The device also includes a connector attached to the first end of the shaft. The device also includes a rod connected to the shaft. The rod comprises a third end and a fourth end. The third end is connected to the second end of the shaft. The rod is about parallel to the longitudinal axis. The device also includes a spring surrounding the rod. The spring is compressible or extendable along the longitudinal axis. The device also includes a stop connected to the rod at a position distal to the spring. The stop resists longitudinal compression or extension of the spring.

Abstract: A method including placing on a surface a first beam having a first end with a first clevis component opposing a second clevis component. A second beam, including a second end having a third clevis component opposing a fourth clevis component, is placed adjacent the first end on the surface. The first clevis component is connected to the third clevis component. A lifter is connected to the first end and the second end, which are lifted simultaneously from the surface while rotating the first beam and the second beam about the connector until the second clevis component engages the fourth clevis component. Connection between the second clevis component and the fourth clevis component then may be completed.

Abstract: A method including placing on a surface a first beam having a first end with a first clevis component opposing a second clevis component. A second beam, including a second end having a third clevis component opposing a fourth clevis component, is placed adjacent the first end on the surface. The first clevis component is connected to the third clevis component. A lifter is connected to the first end and the second end, which are lifted simultaneously from the surface while rotating the first beam and the second beam about the connector until the second clevis component engages the fourth clevis component. Connection between the second clevis component and the fourth clevis component then may be completed.