History of an idea: The seat lever

Helmut Kohake, managing director of Müller-Technik, tried to move his car seat backwards on a cold winter morning. He abruptly pulled back his hand as he touched the lever. The metal part was cold as ice. This would not have happened if it were made of plastic, he thought to himself.

After arriving at the offi ce, Helmut Kohake tasked the development department with the problem. The engineers worked meticulously to develop a lever from plastic and tested the construction in two different injection molding processes – with gas-assisted injection and water injection. The tests were so successful that Müller-Technik issued a patent for the concept.

Approximately ten years later the time had come. Serial production for the first seat lever from plastic began. Volkswagen realized the benefits of a plastic lever. From 2014 on, the levers have been installed in the family vans of the secondlargest automaker in the world ensuring that Helmut Kohake and many other drivers will not get cold hands in winter.

Sometimes it is the simple everyday things or situations that turn an idea into something better.

Helmut Kohake, Managing Director (technical area)

Advantages of the plastic seat lever

  • The car manufacturer can freely choose the design.
  • The seat adjustment lever does not require coating or painting.
  • Production in colors is easily possible.
  • Individual integration areas can be realized on the seat through direct molding (e.g. plug-in holder).
  • Exchanging metal with plastic lightens the weight by up to 33%.
  • Force requirements can be fulfilled according to the requirements specification.
  • No reworking is necessary due to the fabrication procedure (deburring, drilling).
  • Environmentally friendly, 100 % recyclable

Pleasant to touch, robust & inexpensive: 2C Handwheel

Müller-Technik reconciles opposites. A handwheel on a car seat must be able to withstand a lot. At the same time, it should feel good in the hand of the driver. It must be pleasant to touch. And, finally, it must not cost too much.

Our solution: 2C handwheels. Previously, an automaker had to assemble three injection molding parts – the abrasive ring, handwheel and ring – in a laborintensive process while the new component can be completed in one work step. Both components are molded and joined in one injection molding machine, which saves time and money.

The ring consists of a softer more pleasant material than the handwheel whose primary purpose is to withstand strong forces. Incidentally, 2 or 3-component parts have a significantly longer service life than products assembled from multiple components.

Advantages of multiple components

  • Optimal haptics
  • Inexpensive due to fewer components
  • Assembly not necessary
  • Secure manufacturing process
  • No stickiness in heat
  • Resilient surface

We print at all levels

Parents with children know about the practical safety system Isofix. Child seats can be attached especially securely at two hooks that have been integrated into the seat. Müller-Technik makes sure that mom and dad can easily find the Isofix connection in the Audi A3: by providing a printed cover cap. The lettering “Top Tether” (the name of the Isofix system) and a symbol are visible.

The component is rather inconspicuous and could be easily produced if not for the lettering and the symbol that are printed at various levels of the component – once on the profile and once on the inside. Our developers had to put their heads together until they constructed a suitable fully automatic pad print for this part.

Pad printing is an indirect printing process in which the color is transferred through an elastic pad made of silicone rubber from the print form to the plastic part.