A Great Time for Gears
The proliferation of hybrid vehicles and step-gear transmissions are on a roll now and will continue to be for the foreseeable future.
Well over 2 million Toyota and Lexus hybrid vehicles have been sold in the United States since the first Prius appeared in July 2000. Presently, Toyota Motor Corp. offers 12 different hybrid models in the U.S. Of all of the hybrid sales in the U.S., models from Toyota and Lexus account for about 70 percent. Word from Toyota HQ in Japan is that by the end of 2015 it will add 18 additional hybrid models to the 20 it presently offers around various parts of the globe. When that happens, it expects that it will sell 1 million hybrids per year on a global basis, of which about a third will be sold in the U.S.
That goal is by no means a stretch, because in 2012, 236,659 Prius models were sold in the U.S. Bob Carter, senior vice president, Automotive Operations, Toyota Motor Sales USA, once told me that he expects that Prius will become, in the not-too-distant future, more important to Toyota than the perennially best selling (11 years running) Camry.
Meanwhile, Ford is rolling out with a number of hybrid variants of its products, as well as electric vehicles (EVs). You can buy hybrids from Honda and Hyundai. And there are more full EVs and plug-in hybrids on the way.
If you’ve ever taken a look at the “Hybrid Synergy Drive,” which is the powertrain setup used for Toyota hybrids, you’ve probably noticed something that isn’t there: a lot of gears. There are some sun gears and planetary gears. But comparatively few.
Nissan, which offers hybrids and the LEAF EV, has almost completely forgone step-gear transmissions for its passenger cars, choosing to go to continuously variable transmissions (CVTs) instead. Again, a reduction in the number of gears in the powertrain setup.
All of which may lead people to think that conventional transmissions are going the way of the carburetor.
But nothing could be further from what’s really going to happen—from what’s really happening.
Consider this: Chrysler’s Ram brand is offering an eight-speed transmission standard in the Ram 1500. Given that plenty of contemporary sedans have six speeds and are considered to be with the times, eight in a light-duty pickup truck is a remarkable thing, indeed. It is all the more remarkable when you consider that in the not-too-distant past, the Ram 1500 had a standard four-speed transmission.
GM and Ford, which previously collaborated on a six-speed transmission, have announced co-development of nine- and 10-speed transmissions. Volkswagen is working on a 10-speed dual-clutch transmission.
The point is, while there are certainly challenges to the predominance of step-gear transmissions, they’re not going away. The forthcoming CAFE regulations make it mandatory that OEMs have highly fuel-efficient products, which means that not only will eight-, nine-, and possibly 10-speed transmissions become more the norm, but that the gears found within those transmissions need to be produced to even more exacting standards. Consumers will not stand for balky or noisy transmissions. More and better gears. A great time.
Over the years, this Indiana job shop/contract manufacturer developed a specialty in gear making. Now it is taking this specialty to a grander scale. Two large machines for high-precision internal gear grinding are the main anchors of the company’s new precision grinding room.
This manufacturer’s use of live-tool lathes overcomes labor cost in various ways. One of the latest sources of savings involves bringing another operation—hobbing—into these machines. INCLUDES VIDEO.
With so many advances being made in gear grinding technology, where does that leave processes such as hobbing, shaping and shaving? This shop explains its machining methodology.