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Earlier works, coped with the problem of brake noise, described the dynamical behaviour of brake system components or excitation mechanisms, as the stick-slip effect. This work describes a pathway to simulate the dynamical behaviour of lumped mass system, excited by different mechanisms. One part of the paper focuses on the mechanical parameters of a lumped mass system, taking into account the geometry of the brake and mechanical properties of the friction material. This gives rise to the correct description of the energy dissipation into the boundary layer and the systems response resulting (e. g. pad end flutter). As a first step a FEM model of the entire brake is developed. By means of this model the sensitivity of systems eigenmodes regarding different mechanisms of excitation can be calculated. The eigenfrequencies with the highest sensibility of excitation are used for the assessment of the mechanical parameters of a simplified lumped mass system.

While braking cars as well as trucks, a large amount of energy is taken into the brake system in a short period of time. This leads to some problems e.g. cracking of the disc, non-uniform wear of pad and disc. The paper describes methodes to analyze the cracking problem of the disc. It is pointed out, how the pressure distribution between pad and disc can be measured before and after a special test procedure. With FEM-modelling the distribution of normal and friciton forces in the contact zone between pad and disc is calculated. The measurements and the calculations describe a pathway to simulate some reasons and remedys for the solution of the problem.

Clutches and brakes are important elements in automatic transmissions in terms of function, number of parts and design works involved. Among the many design options and variables involved in the clutch and brake design, selection of return and cushion spring types and their characteristics are important for positive disengagement and better shift quality. However, not much information is available on the advantages and disadvantages of various return and cushion spring types, such as Multiple Round Wire Coil Springs, Flat Wire Wave Coil Springs, Disk Springs and Wave Springs. In this paper, the functions and design requirements of return and cushion springs are reviewed. In order to provide some design guide lines for engineers, sample designs of return and cushion springs have been made using round wire coil, flat wire wave coil, disk and wave springs. A comparison of the results in terms of space, weight, cost and transmission performance is also provided.