Method for applying a strap around a load
In one aspect, the present invention contemplates a strapping station that integrates with a machine for wrapping and clamping a strap around a load, particularly a palletized load. The strapping station includes a transfer conveyor and a compression conveyor that is supported to be lowered onto the upper surface of a load to apply pressure to or compress the load during the strapping operation. The compression conveyor is maintained in that position, continuously applying pressure to the load, even as the load is moved for the application of straps at different locations.
1. A method of applying a strap to a load comprising:
positioning a load in a first position on a transfer conveyor in a staging area, the staging area including a compression conveyor positioned over the load in the staging area, the compression conveyor including a compression conveyor frame having first movable conveyor elements supported in a leading portion of the conveyor frame relative to a travel direction and second movable conveyor elements supported in a trailing portion of the conveyor frame relative to the travel direction, the first and the second movable conveyor elements being spaced apart from each other to define a slot that extends across the conveyor frame in a direction transverse to the travel direction,
moving the compression conveyor frame toward the load until the first movable conveyor elements and the second moveable conveyor elements contact the upper surface of the load and apply a compressive force to the load,
applying a strap around the load through the slot while the first and the second movable conveyor elements are positioned against the upper surface of the load such that the strap extends across the upper surface of the load in the direction transverse to the travel direction, and
moving the load in a travel direction within the staging area while the first and the second movable conveyor elements are positioned against the upper surface and maintaining the compressive force on the load.
2. The method of claim 1 further comprising:
moving the load in the staging area to in a second position after applying the strap while the first and the second movable conveyor elements are positioned against the upper surface and maintaining the compressive force on the load, and
applying a second strap around the load through the slot while the first and the second movable conveyor elements are positioned against the upper surface of the load such that the second strap extends across the upper surface of the load in the direction transverse to the travel direction.
3. The method of claim 1 wherein:
the compression conveyor includes at least one belt, and
moving the load within the staging area is accomplished by moving the at least one belt on the compression conveyor.
4. The method of claim 1 wherein:
the transfer conveyor includes at least one belt, and
moving the load within the staging area is accomplished by moving the at least one belt on the transfer conveyor.
5. The method of claim 1 wherein the step of moving the compression conveyor frame toward the load includes powering the compression conveyor frame with a compression drive mechanism.
6. The method of claim 1 wherein the step of moving the compression conveyor frame toward the load includes moving the compression conveyor frame until the first and the second movable conveyor elements apply a compressive force to the load that is greater than the weight of the compression conveyor.