A Fundamental Study on Frictional Noise : 2nd Report, The Generating Mechanism of Squeal Noise of Higher Modes

Abstract

In this paper, we investigated a frictional noise produced when a long steel cantilever was pressed in the radial direction on a rotating thick disk. The results obtained are summarized as follows: (1) With a longer rod, both fundamental and higher mode squeal noises occur. These squeal frequencies are coincident with the lateral natural frequencies of the rod. The squeal frequencies of higher modes are equal to the lateral natural frequency near the longitudinal natural frequency of the rod. (2) Squeal noise of higher modes occurs in two cases. The first case is when contact surface between the rod and the disk is relatively large and the longitudinal vibration increases after a squeal noise of the fundamental mode damps. The second one is when the longitudinal vibration increases in rubbing noise. (3) however, a complete squeal noise of higher modes does not occur without damping of a squeal noise of fundamental mode, even if longitudinal vibration of the rod increases.