Method for producing a stack of metal sheets

Simple SummaryContent extracted from patent full text and abstract with AI.

This patent describes a method for manufacturing stacks of metal sheets (such as those used in electrical machine rotors or stators) by creating individual insulated metal laminations with specifically shaped recesses. These sheets are stacked so that the recesses align to form a cavity with a varying cross-section along the stack. The cavity is then filled with a hardenable material (like thermoplastic or resin), which, once hardened, holds the sheets together securely by mechanical interlocking (form closure), without causing electrical short circuits between the laminations.

Use CasesContent extracted from patent full text and abstract with AI.

• Manufacturing rotor and stator cores for electric motors and generators
• Producing laminated magnetic cores for transformers and inductors
• Automated mass production of laminated metal sheet stacks for various electrical machines
• Applications requiring easily disassembled or repairable laminated stacks, such as maintenance or recycling of electric motor components

BenefitsContent extracted from patent full text and abstract with AI.

• Prevents unwanted electrical short circuits between stacked laminations, enhancing machine efficiency
• Eliminates the need for traditional bonding methods that can reduce tool life or are costly (e.g., gluing or mechanical crimping)
• Enables mass production integration due to compatibility with common stamping and assembly processes
• Allows for strong mechanical cohesion using cheap and widely available filler materials (thermoplastic/resin)
• Supports potential disassembly and repair by choosing filler materials that can be removed if needed (e.g., thermoplastic can be melted)
• Reduces manufacturing costs associated with adhesives and minimizes equipment wear by enabling continuous use of stamping oils

Technical Classifications (CPCs)

Inventors & Applicants

Patent Abstract

The method involves producing painted or phosphated individual laminations (3) with small and large recesses (6, 7) of a preset contour. The individual laminations are stacked on each other to form a stack such that a one-side opened cavity (9) is formed by the recesses along stacking direction (13). A lateral extension (14) of the cavity is varied along the stacking direction. The cavity is filled with hardenable filler material (12) e.g. thermoplastic or resin. The filler material is hardened, and the individual laminations are joined together by a form closure. An independent claim is also included for a laminated core.