Novel production process enables weight savings in new BMW 3 Series

The door panels, manufactured by Johnson Controls, are made using a combination of natural fibres and plastic, which are 20% lighter than conventional components. The seat structures for the driver's seat are said to save between 3 and 4kg depending on the model. "With our innovative products, we are helping BMW make the new 3 Series comfortable and sustainable. We offer high quality, lighter weight components that reduce fuel consumption," said Beda Bolzenius, president of Johnson Controls' Automotive Experience. "We also use renewable and environmentally sound raw materials in the interior components." The non-visible door panel elements for the new BMW 3 Series sedan and sports wagon models are largely made of wood fibre. The natural fibre carrier is directly moulded with plastic. This production method is said to make the door panel considerably lighter. A state of the art process known as groove lamination is used to apply the fabric or leather trim on the door panel. This process involves the trim being joined in recesses, eliminating the need for an additional component and further reducing weight. Four special features characterise the seat structure of the new BMW 3 Series. The use of high strength steel means it is both stable and lightweight, while the low seat back pivot point increases comfort. The structure also offers a very finely graduated recliner to ensure the best sitting position. Adjusting motors using four-pole technology, in some cases with rare-earth magnets that have a stronger magnetic field than conventional ferrite magnets, are used in the electrically adjustable seats. This means they need a smaller installation space and are approximately 200g lighter. With up to four motors per seat, this also enables a significant weight reduction. The seat structures are modular in design and are available with four and eight way functionality for four and five door models. There is also a version with an easy entry function for two door models.