The fascination of the automotive differential has led to the idea to build a second differential unit around a first center unit. Both units have the same axes around which they rotate with different speeds. The potential of double differentials as ultrahigh reduction speed reducers is significant. Only the tooth-count of the gears in the outer differential unit must be changed in order to achieve ratios between 5 and 80 without a noticeable change of the transmission size.
There's never been a better time to put the spotlight on e-drive transmissions and electric vehicles. They're obviously not just coming: they're already here. Just check out any auto show or
showroom. That's why Gear Technology magazine is pleased to present the first installment in a series of chapters excerpted from Dr. Hermann J. Stadtfeld's newest book, "E-Drive Transmission
Guide - New solutions for electric- and hybrid transmission
The south-pointing chariot exhibited at the Smithsonian Institution, Washington, D.C., (circa 2600 BC)is shown in Fig. 1. Although the mechanism is ancient, it is by no means either primitive or simplistic. The pin-tooth gears drive a complex system, wherein the monk on the top of the chariot continues to point in a preset direction, no matter what direction the vehicle in moved, without a slip of the wheels.(1)