Winding cores for material rolls having high roll strain energy, and method for making same

US9212021B2 · kind B2 · utility

Assignee

• Sonoco Development, Inc. · US

Inventors

• David E. Rhodes · Hartsville, US
• John F. Auten · Hartsville, US
• Yiming Wang · Beijing, CN
• Wim van de Camp · Hartsville, US
• Terry Gerhardt · Madison, US
• Lawrence E. Renck · Hartsville, US

Key dates

• Filing date: Feb 4, 2008
• Grant date: Dec 15, 2015
• Expiry date: Dec 31, 2031

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B65H2701/5112
• WIPO field: Handling
• WIPO sector: Mechanical engineering

Abstract

Winding cores for elastically stretched or shrinkable materials are designed to significantly reduce the amount of roll strain energy developed during winding. This is accomplished by building into the core an energy-absorbing zone that can be collapsed by a substantial amount and in a relatively controlled fashion over a substantial period of time under the influence of a continued radially inward pressure exerted by the roll of wound material. The energy-absorbing zone is formed by one or more collapsible layers having repeated atomic regions projecting out of a plane of the sheet and each defining a plurality of normal vectors in different sub-regions of the atomic region, wherein the normal vectors, when projected onto the two-dimensional plane of the sheet, are in a plurality of different directions in the plane.