ディスク・パッド間圧力の均一化によるディスクブレーキ鳴きの低減

摘要

The pressure between a disk and a pad become un-uniform when the pad inclines due to the moment of frictional force applied when braking. The pad stiffness also becomes un-uniform because the stiffness depends on the pressure. The influence of the un-uniformity of the stiffness between the disk and the pad on squeal generation is examined by using a surface-contact-analysis model. To facilitate the stability analysis, the model consisted of a minimum element that can reproduce the squeal vibration. Specifically, the model was composed of a disk with one degree of freedom (out-of-plane direction) and a pad-caliper with two degrees of freedom (rotational and translational). The disk and the pad-caliper are connected by a distributed spring. The analytical result clarified that the coupled vibration of the disk and the pad-caliper became unstable when the pad stiffness was un-uniform, and the self-excited vibration (squeal) was then generated. Additionally, the influence of the un-uniformity of the pressure between the disk and the pad on squeal generation was examined by executing squeal tests. The moment of the frictional force could be counterbalanced by enlarging the load added to the trailing side edge of the pad, which resulted in uniform pressure between the disk and the pad. The results of the squeal test clarified that squeal was not generated when the pressure between the disk and the pad was adjusted to become uniform.%ディスクブレーキの鳴きは，ディスクとパッド・キャリバの運動が達成して発生する自励振動である.鳴きの発生には，ディスクやパッド・キャリパ単体の振動特性だけではなく，ディスク・パッド間の摩擦接触部のばね特性が影響する（1）」4）.摩擦接触部のばね特性を考慮して鳴き発生メカニズムを解明しようとする試みは古くから行われている.その結果，摩擦接触部のばね剛他の分布が非対称になると鳴きが発生することが示されている（5）」刀.しかし，摩擦接触部の剛性が測定されていなかったため，従来の解析では，鳴き実験の結果を再現できるように剛性の大きさが調整されていた.精度のよい鳴き解析を行うためには，実際の摩擦陵触部の剛性分布を明らかにする必要がある.