The Flux chair is a foldable, lightweight designer chair produced by Dutch company Flux Furniture. It is an excellent example of Dutch design that has already been honoured with various design awards. HSV TMP made an important contribution to the engineering for this chair.
Challenge for our R&D team
The unusual thing about the Flux chair is that you construct it by folding a flat sheet of plastic. Although polypropylene-based folding hinges are not uncommon (think of bread bins, for example), the design of this chair takes things to a whole new level. Our R&D team team was faced with a considerable challenge, not only because of the number of folding hinges, but also the fact that these are curved and have to bear a load when the chair is in use.
Molten plastic does not flow easily through thin hinge walls
Limited flow of plastic
To achieve a strong hinge that can be folded hundreds of times, the plastic needs to be perpendicular to the direction of the hinges. We also had to take into account the fact that molten plastic does not flow easily through the thin hinge walls.
Solution: seequential injection
In this case simulating the flow of the plastic in the mould provided a solution. After performing countless simulations we opted for a sequential injection system. This means that the plastic is injected through one gate first and flows through an initial line of hinges, before four other gates take over the flow.
As plastics shrink while they are cooling in the mould, there is a risk of deformation in the finished product. This was also a real possibility in the case of the Flux chair. As well as flow simulations, we therefore also performed an extensive warpage analysis, which gave us a prior insight into the dimensional stability of the finished product.
Our simulations and analyses saved considerable time and costs
Time- and cost-saving
Our simulations and analyses during the engineering process enabled us to create an optimum mould concept before the mould was constructed. This helped our customer avoid time-consuming and costly changes during mould production. We are therefore proud to have played a part in making this award-winning chair a reality.