Abstract
Squeal often generates in car disc brakes. Brake squeal gives discomfort for driver. Also, it is misled abnormality of the system, therefore car maker has many troubles with claims from customers. Disc brake squeal is classified in terms of its generation mechanism. It has been found in previous studies that two types of squeal exist in disc brakes. One is called out-of-plane squeal, and the other is called in-plane squeal. There are many reports that treat the out-of-plane squeal caused by Coulomb friction. Recently, the occurrence of in-plane squeal has been increasing, and the mechanism of in-plane squeal is not yet fully understood. This paper clarifies the characteristic of the in-plane squeal by using an actual machine experimentally. The vibration mode of in-plane squeal is investigated. Additionally, the effect of brake pad thickness on squeal and the frictional characteristics of disc brakes are investigated. From these experiments, the generation mechanism of in-plane squeal is confirmed. A simple analytical model is also set up. The analysis model was consisted of disc and brake pads which are expressed as beams with a concentrated mass model. It is confirm that the characteristics of the unstable vibration agree well with those of the in-plane squeal generated in the floating type of car disc brake. And influence on in-plane squeal by additional mass to rotor using this linear analysis model is investigated.
