New processes enable weight savings in BMW components

Johnson Controls is using new production processes to produce the door panels and seat structures for the new BMW 3 Series.

The door panels are made through a combination of wood fibres and plastics that are claimed to be 20 per cent lighter than conventional components.

Geritt Fluess, sales director at Johnson Controls, told The Engineer that the company is taking a combination of existing, well-known and approved processes to produce the panels.

A process known as groove lamination will be used to attach the fabric or leather trim to the door panel, which involves the trim being joined in the recesses, eliminating the need for an additional component and further reducing weight.

Fluess claimed that the door panel reduces the overall weight of the car, while providing reinforcement to its entire structure. He also said that the door panels would allow different degrees of stiffness to be achieved within the same carrier, making the vehicle more flexible and improving its crash performance.

Meanwhile, the new seat structures for the front two seats save 3–4kg, depending on the model.

The use of high-strength steel in the seats means they are both stable and lightweight, while the low seat-back pivot point is said to offer comfort by fitting to the passenger’s body.

Weight savings also come from the four in-built seat-reclining motors that use rare-earth magnets over conventional ferrite magnets to reduce the weight of each motor by 200g. 

Ulrich Andree, communications manager at Johnson Controls, said: ‘As one of the leading automotive suppliers it is important for us to deliver technologies that enable the OEM to differentiate on the market. This also includes sustainability and efficiency topics such as, for instance, natural fibres and weight saving.

‘If you take just one component from a car its weight-saving potential at first glance might not look like a lot but if you add up various components and systems you end up with a reasonable amount.’