A new Pallet Handling System (PHS) automates part handling for machining centers when parts are mounted to fixtures, whether for a single machine or for a cell of machining centers. Liebherr says its PHS can be installed new or retrofitted onto existing machine tools, including different brands of machines to be tended by the same PHS for untended lights-out operations.
The modular pallet handling systems come in three platforms with payloads ranging from 500 to 6,500 kg. The PHS type 750 can accommodate workpieces with a maximum diameter of 1,000 mm, weighing up to 1,200 kg. PHS 1500 can handle workpieces up to 1,700 mm diameter, weighing up to 2,500 kg, and the PHS 3500 system can handle workpieces up to 2,400 mm diameter, weighing up to 6,500 kg.
Part exchange and part setups are completed and fixtures tended while machining centers are running, increasing production capacity by extending available machining time. A PHS system exchanges a part/fixture in about 60 sec. fixture/pallet storage capacity is expandable via modular design, and rack storage height per part and fixture height are flexible to meet requirements. The system can be expanded by gradually integrating additional machining centers or other processes into the system.
Cell control is accomplished with Soflex PCS standard production and pallet-management software. Control is supplied by the Siemens S7-300 and a mobile operating panel. The user can start small with the simplest cell controller, and upgrade later when looking to add functionality to suit varying batches and increasing volumes of mixed or new parts. The cell controller looks ahead to plan production schedules. Tool data and NC programs are managed by the cell controller, which also flags missing tools or programs, giving the operator time to react before the machine stops.
Access to machining centers and manual loading is possible via an optional front access door. The front-access option allows the user to take a machine off-line and run in manual mode while the other machining centers remain in automatic running mode. Access by overhead cranes is possible, because the top support rail for the moving vehicle is also opened. This capability is useful during NC program development, when parts are required to be machined manually, or when it is necessary to maintain operations if there is a problem with the automation.
Filed Under: Components