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Small components, great effect

Sonova, the global leader when it comes to innovative solutions to hearing issues, has now developed a world first in the shape of a new fast-charging batterypowered hearing aid with an extended battery life, which placed extreme demands on miniaturisation. SFS was brought on board for the connection of the battery contact to the housing. The project was realised thanks to a comprehensive pooling of experience and ideas in close collaboration.

Added Value


  • Development the world’s smallest thread forming screw
  • Fully capable insertion process increased productivity
  • Key technologies (miniature fastener solutions & micro injection moulding) from one source

Aesthetics and functionality in unison

Due to the limited available space, the fastener needed to be just 0.5 mm in diameter! What’s more, a secure process was needed which would enable the fastener to be inserted directly without damaging the delicate plastic housing.

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SFS REMFORM® Ø 0.5 × 2.0 mm

Tiny but tight: pushing back the physical barriers

The stainless steel REMFORM® Ø 0.5 × 2.0 mm realised by SFS is currently the world’s smallest thread forming screw manufactured by cold forming. The entire manufacturing process had to be revamped to create this component, with new demands on tooling, cold forming and thread rolling techniques. In addition to achieving a technological solution, pushing back the previous production limits, a fully capable insertion process was developed, enabling Sonova to considerably increase productivity.

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The fast-charging battery powered hearing aid combines aesthetics and functionality

Small plastic components as part of the overall solution

Stamm, a reliable partner for micro injection moulding, has been producing complex, miniature plastic solutions for Sonova for many years. Only close collaboration throughout and an extensive know-how interchange could enable the required design and functional requirements to be met.

Different technologies from a single source

SFS offers both miniature fastener solutions and micro injection moulding capabilities from one source, reducing the number of interfaces and producing system solutions with every part operating in unison.

Stamm is a member of the SFS Group.

Used technologies

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