Designing plastic parts with integrated hinges formed from the plastic itself is hardly a new idea. These so-called "living hinges" have been around for years on all sorts of packaging and consumer products. But now they show promise for automotive interiors. Engineers at Bayer Corp. have developed a concept for creating thermoplastic polyurethane (TPU) integrated hinges for armrest storage and other interior compartments.
TPU has a lot going for it in these applications. This elastomer family is well known for its high tear strength and dynamic flexural performance, particularly at low temperatures. Bayer has test data from non-automotive applications showing TPU living hinges lasting past one million cycles. And recently, the company introduced a family of aliphatic TPUs whose improved resistance to UV light now makes these elastomers well suited for colored automotive interior parts—not just basic black and dark gray as in the past.
The armrest and integrated hinge would be created during a two-shot molding process. The bottom and the lid would be produced in the first shot from a rigid plastic, such as ABS, while the second shot would add the TPU hinge that joins the two. Depending on the design of the part, the hinge would typically measure between 50 and 100 mils thick. To produce an even bigger bang for the two-shot buck, the second shot could also simultaneously cover the armrest substrate with the same TPU, imparting a soft-touch skin that might otherwise require a separate manufacturing step.
The tooling to perform such a complex overmolding job
wouldn't come cheap, but Bayer engineers estimate that a 5-10% overall cost
reduction would result from living hinges, in part because high automotive
production volumes would minimize the impact of tool cost. The predicted savings
would then come from the elimination of manufacturing and assembly steps as well
as the cost of the mechanical hinges and their fasteners.
It's Alive: A living hinge, molded in a
two-shot process from thermoplastic polyurethane along with the rigid
armrest components, takes the place of a traditional mechanical hinge for
an automotive armrest.
Are they robots or androids? We're not exactly sure. Each talking, gesturing Geminoid looks exactly like a real individual, starting with their creator, professor Hiroshi Ishiguro of Osaka University in Japan.
Truchard will be presented the award at the 2014 Golden Mousetrap Awards ceremony during the co-located events Pacific Design & Manufacturing, MD&M West, WestPack, PLASTEC West, Electronics West, ATX West, and AeroCon.
For industrial control applications, or even a simple assembly line, that machine can go almost 24/7 without a break. But what happens when the task is a little more complex? That’s where the “smart” machine would come in. The smart machine is one that has some simple (or complex in some cases) processing capability to be able to adapt to changing conditions. Such machines are suited for a host of applications, including automotive, aerospace, defense, medical, computers and electronics, telecommunications, consumer goods, and so on. This discussion will examine what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.