The driving factors and actual market trends for construction machinery, their impact to driveline components, and how requirements can be addressed by innovative transmission and axle concepts reveal the challenges for future innovation.
Before concentrating on these demands, it might be helpful to have a glance back at the history of construction machinery drives.
Initially, robustness and reliability were the essential success criteria for construction machinery drives, and design engineers had to determine the specific loads of these applications. At the beginning of the 1980s, special emphasis was placed on the development of an improved driving/working performance match. Also, operator comfort became a factor for market success of working machines.
This led to improved shift quality, more ergonomic operating elements, and automated shift sequences. An additional achievement was the interaction between drive systems and working hydraulics, which has only become possible due to the use of first electronic control units.
Today’s challenges are closely related to the economic use of resources and the preservation of the environment, requiring efficient drive solutions with optimum fuel utilization and minimized environmental impact due to emissions.
Reduced consumption, improved efficiency, and yet highly productive driveline concepts will be the key to meet these demands. ZF encounters these challenges with new developments in the field of continuously variable and hybrid technology.
High loads at low speeds in combination with high dynamics are just some of the requirements for construction machinery, and those criteria are met with much improved efficiency by new ZF CVT transmission technology.
The fully powersplit, continuously variable technology benefits from the long-term experience gained on the agricultural machinery sector and offers significant consumption benefits and productivity increases for the vehicle owner.
A trend toward lower engine speeds and the demand for engine stabilization by a constant speed concept are the future challenges on the construction machinery market. The continuously variable cPOWER from ZF meets both requirements and surely is the beginning of a new technological era in construction machinery.
With the Efficiency Package, ZF is already setting benchmarks with up to 20% fuel savings and up to 40% productivity increase. The ZF hybrid component on the basis of the well-proven ERGOPOWER series is the logical evolutionary step toward an electric drive and is keeping pace with the trend toward more environmental protection and preservation of resources.
ZF offers hybrid technology covering electric machines and complete hybrid systems from one source. ZF ERGOPOWER hybrid stands for a considerable reduction of consumption, an increase of work output, and a significant reduction of exhaust emissions.
Construction machinery ranging from wheel loaders over diesel lift trucks to excavators can be equipped with the future oriented and environmentally friendly ZF technology.
An optimization of driveline components and their functional interaction can generate maximum results in terms of fuel consumption, emissions, and performance of the machine. This also means that ZF design engineers of future drive components have substantial overall vehicle system and application know-how and achieve optimum solutions by this. ZF has built up competence from wheel to exhaust pipe.
In conclusion, it can be said that although the major part of losses does not occur in the transmission and axle, an intelligent driveline design can provide an improvement of fuel efficiency of up to 30%, thus allowing a significant contribution to emissions reduction and in no way affecting productivity negatively.
Herman Beck, Vice President, Construction Machinery Systems, ZF, wrote this article for SAE Off-Highway Engineering.