Generation mechanism of in-plane squeal on disk brake (Investigation of squeal generation conditions using low-degree-of-freedom analysis model)

Abstract

A brake that presses a friction material against a rotating disk is called a disk brake. And it is widely used in industrial machines and automobiles. A noise called squeal may occur during braking. Squealing is generally unpleasant and can impair the performance of the machine on which the brake is mounted. When a machine squeal occurs, countermeasures such as provide dampening may be taken. However, it is difficult to take effective countermeasures unless the mechanism of squeal generation is clear. It has been clarified in previous studies that the natural vibration of the disk greatly affects the generation and frequency of the squeal. In particular, the generation mechanism of out-of-plane squeal, which has been extensively studied for a long time, has been elucidated and countermeasures have already been taken. On the other hand, when out-of-plane squeal was dealt with, in-plane squeal became a problem. In-plane squeal is characterized by large vibrations in the in-plane direction and small vibrations in the out-of-plane direction as if the disk were twisted. In this study, we clarified the generation mechanism of in-plane squeal using a low-degree-of-freedom analysis model. Since the conditions under which in-plane squeal occurs have also been investigated, it will be useful for eliminating in-plane squeal in the future.