Stability and squeal analysis of an external shoe brake using complex eigenvalue method

Mechanical brakes play an essential role in operation of EOT (Electric Overhead Traveling) cranes; however, due to the complexity of these structures and instability of the system during braking period, failure occurs frequently in some cases. In this paper, the squeal phenomenon of an external drum brake which is considered as a dynamic instability phenomenon has been studied by using complex eigenvalue method in ANSYS Workbench environment. In order to validate our method and results, since the squeal analysis of an external drum brake has not been studied before, the squeal and mode coupling phenomenon in a disk brake was analyzed. The results demonstrate that at the time of operation of the mechanical brake system, self-excited vibrations due to mode coupling has caused a dynamic instability known as brake squeal. This phenomenon, in addition to generating a screak, has a destructive effect on the mechanical brake system. To optimize operation of the system and prevent above-mentioned effects, coefficient of friction was decreased while the brake force was increased, therefore it is recognized that a reduction of 30 percent in coefficient of friction has caused 65 percent increment in stability of the system.

Stability and squeal analysis of an external shoe brake using complex eigenvalue method Keywords:

External shoe (drum) brake , self-excited vibrations , mode coupling , brake squeal