Date of Award
This design report records the actions taken by the Spin to Win team to optimize and redesign a cutter assembly in a dual rotary sheeter, as well as design a gear reduction in the same assembly. The optimization and redesign of the cutter system focuses on two main factors, inertia and torsional stiffness. The sponsor for this project is MAXSON Automatic Machinery.
Wear and tear on a machine and its parts could be costly or even jeopardize the integrity of the system. Spin to Win came up with a redesign that can theoretically decrease the inertia by up to 40% and grant an increase of the torsional stiffness of the cutter assembly. The gear reduction will change the motor that can be used to propel the system, including a 1.8 : 1 reduction allowing for a smaller motor, thus lowering the cost of the entire assembly. By lowering the inertia and increasing the stiffness of the cutter system MAXSON could see longer part life and less wear as well as lower overall system costs.
The optimization and redesign solution incorporates a wheel and spoke design to add torsional stiffness and decrease inertia. The spokes are inserted along the cutter on an inner shaft and are connected to the outer shell to give the design the added stiffness in the direction of rotation. A prototype was created to show the ease of assembly of the redesign and the apparent decrease in inertia from the current cutter design. The prototype has design considerations to accommodate some of the existing hardware, so that the system integrates into the sheeter system seamlessly.
The design created by Spin to Win suffered in terms of manufacturability, and a simplified design was created for testing. The tests themselves encountered unexpected difficulties flowing to the design of the tests for the available equipment. In the end, the viability of the design was not definitively proved but was suggested, paving the way for further work.
Graziano, Joseph; King, Joshua; Kross, Nathan; and O'Connor, Tom, "Optimization and Redesign of a Dual Rotary Cutter" (2017). Mechanical Engineering Capstone Design Projects. Paper 25.