In purely electric vehicles and in numerous hybrid or plug-in hybrid vehicles, electric drive axles are used. For all-wheel drive applications often two drive axles are used. The main components of such a drive axle are the electric machine, transmission and power electronics. The transmissions have the main functions of speed adjustment and speed compensation between the two driven wheels of the axle, as with conventional drives.
The requirements of low costs, light and compact design and low weight are increasingly leading to highly integrated solutions. In the architecture of such axels, either axially parallel or concentric arrangements of the output shafts or wheel drives on both sides are pursued. Each with advantages and disadvantages in terms of complexity and installation space requirements. It has been the same up to now that first the speeds are reduced and then the power is split between the two drives (differential function).
With the objectives
a new type of structure for an electric drive axle was created at pi³ GmbH.
At the beginning of 2021, pi³ GmbH submitted an application for funding in the WIPANO program, funding focus "Companies - Patenting" of the German Federal Ministry for Economic Affairs and Energy. The grant notification was issued at the beginning of February and the starting signal for the work packages was given in the second half of February.
In the meantime, novelty and commercial exploitation by patent attorneys and external service providers have been rated positively. Advice on registering abroad has also taken place. Accordingly, a property right application was prepared and submitted to the European Patent Office.
However, industrialization by pi³ GmbH is not planned. The components of the new integrated drive axle are known from conventional drives and there is sufficient production capacity for this, be it with established vehicle manufacturers or with their suppliers. pi³ GmbH will issue licenses to interested manufacturers and will be happy to support and engage in their projects.
The compactness of the new integrated drive axle results from very good and even component loads, and improvements in the area of acoustics can be expected accordingly. The consistent use of identical parts compensates for the increased complexity compared to known solutions.
The function of a differential lock can be added easily. The electrical machine can also be separated from the wheel drives in an elegant manner.
Curious? pi³ GmbH looks forward to inquiries and will present the new integrated drive axis at upcoming conferences.
Burkhard Pollak, March 2021