Yoshio Terauchi

Bio: Yoshio Terauchi is an academic researcher from Hiroshima University. The author has contributed to research in topics: Non-circular gear & Spiral bevel gear. The author has an hindex of 14, co-authored 61 publications receiving 592 citations.

Dynamic Behavior of Planetary Gear : 1st Report Load Distribution in Planetary Gear

Abstract: In the planetary gear, the inequality of load distribution arises on each planet gear because of random errors of manufacture and assembly. This phenomenon results in an increase of load to each part, the occurrence of vibration, and a drop in efficiency of planetary gear systems. Though there are a number of studies which are connected with load distribution, many of them are static studies. However, in fact, the dynamic behavior of load distribution in driving is complicated because of the influence of the deformation in each part, dynamic characteristic of the system. Therefore, to explain these relations, a systematic experimental work was carried out using Stoekicht planetary gear(Type 2K-H) with spur gears. Consequently, the following items are explained in this paper : (i) The mean values of load distribution among the planetary gears are nearly equality, but variations of dynamic tooth loads grow large in the high-speed range. (ii) Even if load distribution is equality, it happens that gear tooth dynamic loads largely.

Dynamic Behavior of Planetary Gear : 7th Report, Influence of the Thickness of the Ring Gear

Abstract: The authors studied experimentally the influences of the thickness of a ring gear on the fillet stress of the ring gear and the load distribution among each planet gear. The planetary gear used in this study is a single-stage Stoeckicht planetary gear (Type 2K-H) constructed with spur gears. The results are as follows : (i) The fillet stress of the tension side in the ring gear of a toothed thin-ring is smaller than that in the ring gear of a toothed thick-ring. But the fillet stress of the compression side in the former is larger than that in the latter. (ii) The influence of the eccentricity of the ring gear is sufficiently eliminated by using a ring gear floated with gear coupling, independently of the thickness of the ring gear. And the mean load distribution rates for each planet gear are nearly equal.

On the Relation between the Run-Out Errors and the Motion of the Center of Sun Gear In a Stoeckicht Planetary Gear

Abstract: The authors considered a single-stage Stoeckicht planetary gear (Type 2K-H) as a model which took the tooth stiffness and the run-out errors of each gear and so on. And the authors statically analyzed the relation between the run-out errors and the motion f the center of the sun gear, and further compared the calculated results with the measured ones. The conclusions are as follows : (i) The motion of the center of sun gear draws a trochoid curve. (ii) In the torque of higher-speed shaft, there is a variation whose frequencies coincide with the number of the relative revolutions of each gear for carrier, and also there may be a variation whose frequencies coincide with the number of the revolutions which can be obtained by adding or subtracting these numbers of the relative revolutions.

On the effect of the tooth profile modification on the dynamic load and the sound level of the spur gear

Abstract: Measurements of the gear noise and the dynamic load acting on the meshing teeth of the gears with profile modification and without profile modification which are shifted by different amounts of addendum modification were carried out using power-circulating gear test rigs until a surface failure caused by scoring was observed. According to the experimental results of the gear noise and the dynamic load it is clear that the dynamic load acting on the meshing teeth decreases due to profile modification and that the gear noise of the gears with profile modification is lower about 5 dB than that of the gears without tooth profile modification. Further, the sound pressure levels at all the pass frequencies, the mesh frequency and the 2nd harmonic of the mesh frequency of the gears decrease at the incipient stage of scoring.

Influence of Carrier and Gear Manufacturing Errors on the Static Load Sharing Behavior of Planetary Gear Sets

Abstract: In this paper, a state-of-the-art contact mechanics model of a planetary gear set is employed to study the effect of a number of manufacturing and assembly related carrier and gear errors on the load sharing amongst the planets Three different groups of errors are considered: (i) time-invariant, assembly-independent errors such as carrier planet pinhole position errors, (ii) time-invariant, assembly-dependent errors such as planet tooth thickness errors, and (iii) time-varying, assembly-dependent errors such as gear run-out errors With such errors present, planet load sharing characteristics of an n-planet system (n=3 to 6) is investigated for different piloting configurations under quasi-static conditions Load sharing behavior as a function of key manufacturing errors is quantified and design guidelines are proposed for better planet load sharing behavior