The growth of the EV market is powering continued innovation at Oberg. The industry demands tools that can efficiently produce very high precision, interlocked motor lamination stacks of ultra-thin material (0.008”/0.20mm). Since the entire stack is built within the tool, high-precision manufacturing equipment is required to meet the tight tolerances that ensure each individual lamination successfully interlocks to the one below it. After a complete stack is built, it quickly needs to be ejected while the next stack is stamped—all without slowing the high-speed press.

Drawing on 70 years of tooling expertise, Oberg’s engineering team developed an innovative solution. The tolerances and design of traditional lamination stakes were modified to accommodate the thinner materials. A 3-D model of the tool helped us ensure excellent material utilization, ease of service and maintenance. Our automation team designed proprietary auxiliary equipment to provide upward pressure on the stacks in formation, layer by layer, in the stamping tool. They also created a method to remove each completed stack without interrupting the ongoing stamping operation. The new design utilized the capabilities of our ultra-precision wire cut EDM and jig grinding equipment.

The Results

Because the new stamping system stays up and running with little maintenance, it offers a smart solution to EV companies looking for high precision and low cost of ownership. With easy maintenance and long-life performance between servicing and rebuilds, the new tooling delivers great efficiency and effective material utilization while minimizing press downtime.

Project Overview

  • Processes: 3-D engineering modeling; Automation solutions; Ultra-accuracy wire EDM and jig grinding; MDP® proprietary surface grinding
  • Challenge: Efficiently produce high precision interlocked motor lamination stacks of ultra-thin material
  • Solution: Modified tolerances and design of traditional lamination stakes for thinner materials; Reviewed 3D design model of the tool to ensure efficiency and ease; Designed proprietary auxiliary equipment to create and expel stacks