Utility vehicle lightweight chassis with built-in wheel alignment mechanism
A novel, non-driven and rigid chassis for utility vehicles is presented, which offers a significant weight advantage and suspension properties. The chassis is designed especially for trucks, trailers and busses.
Rising energy costs demand improved transport sector efficiency, which can be achieved with lightweight construction technologies. As the maximum admissible total weight of utility vehicles is legally restricted, chassis weight savings directly allow an increased potential payload capacity. Wheel alignment is one key factor for driving stability and tire wear. However, the chassis construction design is tied to certain boundary conditions. Mechanical requirements, such as resilience to bending moments (especially at the trailing arms) have to be fulfilled. Geometrical aspects, such as the placement of suspension elements, have to be met to keep ride height at a miminum. Weight savings by use of modern materials (e. g. composites) often fail due to high costs and available chassis designs. Further cost saving can be achieved by minimizing production tolerances. However, production tolerances require post-production chassis adjustments that bare significant additional costs.
A scientist from the University of Applied Sciences Hildesheim/Holzminden/Goettingen (HAWK) has developed a rigid, non-driven chassis for utility vehicles (Fig. 1) that offers a significant weight advantage and improved suspension properties. It includes a built-in mechanism for cost-effective wheel alignment. The presented chassis, even when fabricated with standard steel components, offers a significant weight advantage compared to conventional chassis designs. One key advantage of this new design is that primarily pressure and tensile forces are being transmitted, while bending moments are mostly avoided. Thus, the chassis can also be produced from carbon fiber-reinforced materials, which would result in enormous weight savings. The ring-shaped upper braces allow the placement of suspension elements close or even directly above the axle, which leads to direct force transmission into the suspension, while the dropped lower brace keeps the overall height low. Altogether, this novel design significantly improves suspension properties and helps constructing weight-optimized trailing arms. Furthermore, the adjustable upper cross braces allow easy and cost-effective wheel alignment and compensation of production tolerances.
Fig. 1: Rigid, non-driven lightweight chassis for utility vehicles. (Source: Prof. Dr. Frey, HAWK)
- Energy/fuel savings due to lightweight advantage
- Cost savings due to cost effective wheel alignment
- Increased payload due to low height and tare weight
- Optimized suspension properties through direct force transmission into suspension
- Reduced wear due to minimized unsprung mass
- Axles of trucks, trailers and busses
- Suitable for electric vehicles (e-mobility) due to easy integration of electric motors close to wheel hubs
- Axles of vehicles with hydrogen drive conceivable
The mechanical stability was tested by experiment and simulations. CAD drawings of all parts are available. A demonstrator is available.
US patent granted: US1220663B2
European patent granted: EP3257691A1
Chinese patent granted: CN107521300A
Patent holder: University of Applied Sciences and Arts Hildesheim/Holzminden/Goettingen (HAWK)
Press release (in german) including video: "Light axle: less fuel consumption, lower production costs"
Direct link to the video (youtube): "Lightest 9to axle ever built"
Flyer IAA Commercial Vehicles 2018: "Lightest 9to Axle Ever Built"
World premiere at IAA Commercial Vehicles 2018: "HAWK presents lightest 9to truck axle of its kind"
Dr. Mirza Mackovic
Patent Manager Technology
Tel.: +49 (0) 551 30 724 153
Tags: Automotive engineering