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Currently, digital audio source such as a compact disk (CD) and a digital audio tape (DAT) has come to be mounted in cars to complement the sophisticated audio system . To mount these new functions in the limit set space, however, the conventional source such as the FM/AM tuner must be built more compact and lightweight. On the other hand, to view the FM/AM tuner perspective from the standpoints of set design and manufacture, there are various problems such as given below. Set variations are flung from those for the U.S.A. and Europe to those for Japan. It is difficult, if not impossible, to design the set designer for each of these set variations because of the limited designer availability. Also, amid the tendency for world production base to be spread and increasingly numerous, high quality level is of the utmost importance for audio sets no matter where are manufactured. This paper describes an effective solution to these problems.

The world’s first vehicle with a half-toroidal CVT POWERTOROS Unit has been manufactured since November 1999. This continuously variable transmission (CVT) has a torque capacity of 390 N-m and ratio coverage of 4.33. In recent years, demand for a next-generation half-toroidal CVT that provides better fuel economy and ease of assembly and mounting has been growing in response to global environmental issues. The authors developed a new halftoroidal CVT that offers a wider ratio range, a more compact size, higher torque capacity, and higher efficiency. Major features of this new half-toroidal CVT include a gearedneutral system and a power-split system. We successfully downscaled the current CVT by eliminating conventional launching devices, such as the torque converter, friction clutch, etc., and focused our energies on a geared-neutral system. In concert with such steps, we achieved higher efficiency in the mid- to high-speed ranges by using a power-split system.

Temperature rise in traction contact areas is one important factor that influences traction coefficient. For examining the influence of temperature rise on the traction coefficient, it is necessary to first clarify temperature rise in the traction contact area. In this article, temperature rise in the traction contact areas is discussed in three major parts. First, measured temperature distributions on the traction contact surface under conditions of high rolling speed and minute amounts of sliding and spinning, such as those which are found in a toroidal CVT, using a twin-disc test machine and thin-film platinum sensors are shown. Second, the above experimental results are compared with results from a traction analysis program (REIB99). Characteristics of calculated results were qualitatively in good agreement with measured results.

Maintaining stability in the variator control system after quick torque changes is an important factor in achieving smooth mode changes in a power-split CVT system. In this paper, the ratio-changing characteristics of a half-toroidal CVT variator with hydraulic and mechanical loading devices are analyzed using a newly developed analytical model under dynamic load transmission. The ratio-changing characteristics of a variator with a mechanical loading device show a large overshoot after quick torque changes. In the case of a hydraulic loading device under constant application of axial pressure, it has been demonstrated that the ratio-changing characteristics are stable both theoretically and experimentally.