2K ear tips with filter assembly

2K precision injection moulding and automatic filter assembly

When one of the leading brands in hearing protection approached De Beer Plastics, we had already been producing millions of TPE ear tips for many years. The request to replace silicone was therefore nothing new to us. Two-component injection moulding and automated assembly had also been part of our expertise for quite some time.

It was precisely the combination of these three techniques that made this project so interesting: a challenge in which the machine, the mould, the materials and the automation all had to be perfectly coordinated.

  • Very soft medical-grade TPE – combined with a PC-ABS filter holder

  • Complex 2K moulds with anti-seizing slides

  • Automatic in-line assembly of micro filters

Results to be proud of

Simply a really lovely product

The moulding, the weld seams, the fins and even the colouring of the material: with parts this small, a perfect finish is a matter of the utmost precision and controlled processes.

100% quality control

During assembly, a 100% check is automatically carried out to ensure that the filter is correctly positioned. Using a special laser, we can detect even the smallest, transparent filter inserts.

Special production cell

Every component of this specialised production cell has been fully optimised for the manufacture of these 2K ear tips: from the injection moulding machine’s cylinder and the robot to the filter feed system and even the dosing unit for the colourants – everything works perfectly!

I want that too

How did we achieve this?

As specialists in the processing of thermoplastic elastomers, we are frequently asked about replacing silicone with TPE. We now have a wide range of compounds at our disposal, enabling us to offer high-quality alternatives to expensive and labour-intensive silicone products. So the choice of material was an easy one.

The real challenge here was combining this very soft TPE with a handle made of PC/ABS. As these two materials do not naturally bond together, the design had to incorporate an alternative solution: namely, a mechanical connection.

What made it even more challenging was that the handle weighs just a few tenths of a gram, meaning the injection volumes were too small for our standard 2K machines. For this project, we therefore used a special machine, which was configured entirely to suit this project.

Automatic filter installation

Our client used to have the handles and filters fitted manually by staff at a sheltered workshop. This involved two extra steps compared to the current process at De Beer Plastics. There was therefore significant potential to improve production efficiency.

The final step – fitting a filter – was no easy task. The filters, with a diameter of just 4 millimetres and weighing 0.03 grams, must be positioned precisely before being pressed into the base of the handles. The entire sorting and feeding mechanism that had to be developed for this was, above all, extremely miniature and precise. Various sensors and a laser ensure that the filter is always fitted correctly.

Partnership with De Beer

Our client really put us to the test with this project. They made it clear that they didn’t just want us to replace the silicone ear tips with a TPE version, but also to develop a 2K variant of them and handle the assembly as part of the same project.

And although we’ve had to scratch our heads over this project at times, we don’t shy away from challenges like this. It wasn’t a given that everything would go to plan as we’d envisaged. But by continuing to test, adapt and optimise, we’ve ultimately created a high-quality production cell for the finished product.

Do you have a challenge for us? We’d be happy to take it on and see it through to a successful conclusion.

Contact

How can we help you?

Business Development Manager

Laurence Warmenhoven

Call Laurence Email Laurence

Are you looking for a reliable and competent partner to manufacture your products?

  • In-house mould making and R&D for co-creation

  • Ample capacity across more than 100 machines in three factories

  • A proven track record in challenging projects

Moulding challenges into Reality

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