Reinvented wheels support heavy loads

Versatile wheel blocks help engineers build better transfer cars. Area Manager Mannesmann Dematic Corp., The corrosion-resistant, die-cast aluminum housing, enclosed on five sides, protects the travel wheels. In this shuttle conveyor application, a box palletizer transfers pallets onto a conveyor then to a shuttle conveyor for final warehousing. Each shuttle conveyor consists of four wheel blocks in a central drive configuration: one motor driving two wheels with two idler wheels. A complete travel unit uses a special flywheel drive with cylindricalrotor motor for smooth starting. Sliding-rotor asynchronous motors for controlled-drive requirements are also available. Imagine hauling something that weighs as much as 15 SUVs. Nextgeneration wheel blocks that support 88,000 lb make such applications possible. In many automation systems, material moves horizontally from onearea to another by way of conveyors or travel systems supported on wheels. Wheels, used for scrap transfer, bulk handling, mold transfers, or general moving applications, are typically found on transfer cars, shuttle conveyors, scissors-lift tables, and turntables. When designing a wheel system for transfer cars, traditionally, the first step is to determine the wheel size, then design or select the proper axle. Engineers must then establish the correct pillowblock bearings for support based on the axle diameter, distance, load, and speed, and design the car's undercarriage to support the entire package. Finally, they must determine how to get power to the wheel. Typically, this is accomplished with a chain and sprocket connection to a gearbox and motor. Many companies still use this traditional approach, but improvements in wheel design may make for safer and more cost-effective production. One new design, for instance, the Demag Travel Wheel System from Mannesmann Dematic Corp., Cleveland, consists of what is called the "DRS Wheel Block," a preassembled wheel, bearings, and support in a compact, adaptable housing, along with a gearmotor and