Lifting system for containers as an interface to the AGV

Details MTF Technik Hardy Schürfeld GmbH & Co. KG

Task: Buffering of containers as an interface to the driverless transport system

An existing automated guided vehicle (AGV) transports an empty container measuring 600x400x280mm to a plastic injection molding machine.

After the empty container is handed over, the AGV should pick up a filled container on a second level and transport it to the customer's warehouse or for further processing.

An interface system is intended to take over four empty containers from the AGV one after the other and temporarily store them. It is important to ensure that there is sufficient space between the individual container positions to compensate for tolerances in the AGV's container delivery.

If four empty containers are present in the intermediate buffer, they should be positioned in a defined manner and then transferred to a lifting station.

The lifting station is designed to provide the four empty containers at a height of 1,750 mm to a handling device for loading.

Cones of rubble should be avoided.

Once the four containers are filled, they should be simultaneously transported to a collection level at a height of 600mm and made available there for collection by the AGV.

Safety aspects must be taken into account during plant planning.

Solution: Buffer system on 3 levels with electric lift

Development of a buffer system with an electric lift with three levels.

On the empty container conveyor belt, pneumatic stoppers are first lowered from above, ensuring that each container picked up by the AGV travels to the stop in the conveying direction. The presence of empty containers is monitored by sensors.

The conveyor belt is 1,800 mm wide (usable width 1,755 mm) and thus offers a total of 155 mm of clearance for four longitudinally arranged containers, each 400 mm wide. This gives the AGV sufficient positioning tolerance to deliver the containers side by side.

If four empty containers are present on the conveyor belt, a pneumatic pusher presses sideways against the containers and positions them as a "package" on one side of the conveyor belt.

Once the "package" is positioned, the stoppers located in the conveying direction lift, and the four containers can be transferred parallel to the lift conveyor and from there moved into the filling position. The usable width on the lift conveyor is reduced to 1,605 mm.

The containers in the filling process are moved approximately 1/3 of their length after reaching 50% capacity in order to reduce the size of the debris cone.

During the filling process, the AGV places four more empty containers on the conveyor belt.

Once the filling process is complete, the boxes are transferred to the lower level of the conveyor belt – again as a “pack of 4”.

Since the AGV can only deliver/retrieve one box per docking operation, the filled boxes are individually stopped pneumatically on the conveyor belt. Only at the respective pickup position is the box released for handover to the AGV.

Details MTF Technik Hardy Schürfeld GmbH & Co. KG