SPEAR (Self Positioning Elevate And Release)
Time consuming tasks on construction sites generally revolve around crane operations and material handling. These operations also present risks to workers safety where moving or dropped objects can result in injuries to those working near the load.
So, can lifting and movement of loads by crane be made to be automatic, such that workers no longer need to be near moving loads? The answer is “YES”, with the SPEAR hook and catcher.
The SPEAR hook is an automatic mechanical catch and release hook which will both speed up lifting time, and increase safety on any lifting operation. The SPEAR can either be attached to the existing crane hook with a shackle or it could replace the crane hook altogether by attaching directly to the crane block. See below explanation of how it works and a video demonstration of a working model.
How does it work?
The SPEAR uses 3 studs in a cylindrical catcher (attached to the load) and a solid cylindrical SPEAR both made of steel. The SPEAR has a track (see below) built around the exterior which, when inserted into the catcher rotates around the studs to the first position. When lifted in this position the SPEAR then rotates to the second ‘lift’ position, where the studs act as lifting points for the load. When the load and catcher is landed, lowering the SPEAR causes it to rotate to the third position in the track, and when lifted the SPEAR is released out of the studs. This motion allows the load to be safely picked up, moved, and released all without any worker intervention.
See the video below showing how it works using a 3D printed model.