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An increasing number of chain systems have used low cost blade tensioners. However, its functional mechanism had not been logically figured out. One reason for this is that a blade tensioner generates large transversal vibration. Consequently, in the case of the longitudinal model, the load prediction accuracy was inadequate. Accordingly, a link-by-link model was created, allowing transversal vibration to be taken into account. As a result, the features of a chain system using a blade tensioner were clarified, thus enabling the chain load and behavior to be predicted with a higher degree of accuracy than before.

The mechanism of noise production in engine accessory drive belts was discussed. Applying geometric considerations to the transversal vibration of the belt, which is one cause of belt noise, the research showed that vibration of the belt is affected by fluctuations in the rotational speed of the crankshaft, and that the amplitude of the vibrations fluctuates cyclically. The cycle of this amplitude fluctuation is synchronous with engine speed, and for a 3-cylinder gasoline engine, its frequency is the (1.5*n)th engine rotation order. The spectrum pattern of belt vibration therefore shows components of the natural frequency±(1.5*n)th orders. The research demonstrated that at engine speeds at which the natural frequency±(1.5*n)th orders and the (1.5*n)th order frequencies, the engine excitation orders, are identical, multiple engine orders excite resonance in the belt, producing a high degree of belt vibration.