Cutting the weight of components by even a few percentage points can be a difficult task for suppliers and OEMs, but in Germany Johnson Controls, not satisfied with a 30% weight reduction in a rear-seat backframe, is now aiming to reach a 40%-plus target for a new seat design using fiber-reinforced materials.
The company is developing the advanced seat at its Burscheid headquarters together with industry partners and support from the German Government’s Ministry of Education and Research as the three-year CAMISMA (Carbon Fiber/Amid-/Metallic Structural Interior Component Multi-material Approach) project.
Referring to the earlier seatback-frame work (previously described by AEI at www.sae.org/mags/aei/9690), Dr. Andreas Eppinger, Vice President Technology Management, Johnson Controls’ Automotive Experience, said: “We will continue to develop additional alternative, even lighter-weight materials with our partners in CAMISMA.” The project is a salient part of the Ministry of Education and Research’s program, “Innovative Materials for Industry and Society,” which aims to accelerate technical solutions via partnerships between both economic and scientific stakeholders.
CAMISMA particularly aims to support the replacement in automotive applications of steel and light alloys by fiber-reinforced composites (FRC), particularly carbon fiber, to complement the auto industry’s aggressive fuel and exhaust emissions reduction R&D.
As always, the stumbling block for carbon-fiber use is both cost and the added complexity and resultant time involved in manufacturing components incorporating the material. CAMISMA is focusing on reducing these drawbacks.
Said Dr. Matthias Berghahn of CAMISMA partner Evonik Industries: “We are pursuing ways to make high-volume production economically possible.” The difficulty of making ever thinner, lighter weight steels is driving the need for new materials and design.
Eppinger and Berghahn regard the development of seat structures as exemplifying a solution for the auto industry’s use of economically priced FRC materials. It would also provide a path for the interfaces of FRC components and metal-based vehicles. With that aim, a concept seat is now being developed and tested potentially for manufacture.
The objective is to achieve more than a 40% weight reduction when compared to a conventional metal-based design.
As well as Johnson Controls, Evonik, and the German Ministry, other partners include Jacob Plastics, Toho Tenax Europe, and the Technical University of Aachen.
Separately from CAMISMA, Johnson Controls is working on improved seat packaging for some vehicles that also brings weight saving. If that design were allied to the FRC work, the opportunity for additional mass reduction might be furthered.
Eppinger stated: “Our Slim Stow Seat enables us to set new standards in foldable rear seats in pickups. When stowed it takes up 33% less space and is lighter weight compared to traditional rear truck seats. It also improves visibility when stowed since the seatback is lowered 100 mm.”
Weight savings comes from a 30% reduction in the use of materials.
The seat panel comprises two components: an upper part that is a tubular frame featuring the child seat attachment points and defined side bolsters, and the lower part with a stable arm that carries the seat pad, which features 50% more foam than usual in the relevant areas.