Shin-ichi Ishiyama

Backing plate for disc brake with different damping layers for brake squeal

A damping pad for preventing brake squeal includes: a first metal plate with a brake shoe fixed to one surface thereof; a second metal plate; a third metal plate; a first damping layer disposed between the other surface of the first metal plate and one surface of the second metal plate, and composed of viscoelastic material for high temperature use having a maximum loss factor at a temperature of 50° C. to 100° C.; and a second damping layer disposed between the other surface of the second metal plate and one surface of the third metal plate, and composed of viscoelastic material for low temperature use having a maximum loss factor at a temperature of 0° C. to 30° C. Since the first and second damping layers are formed of different damping materials having different temperature ranges for good damping efficiencies, the use of different kinds of damping materials are employed, so that vibrations which may cause the brake squeal are damped through a wide temperature range, thus preventing the brake squeal.

THE APPLICATIONS OF ACOUST/BOOM - A NOISE LEVEL PREDICTING AND REDUCING COMPUTER CODE

Noise level prediction computer code ACOUST/BOOM has been developed to analyze the sound pressure radiated by a vibrating structure and calculate the acoustic resonance of the field. The program is based on the numerical analysis computation of a sound wave equation in a three-dimensional field using the boundary element method. The boundary element method uses simplified input data, reduces computation time and cost, and produces highly accurate results. Applications have been performed on sound radiation analysis for engine oil pan, engine head cover and horn type speaker and also on the acoustic analysis for sedan compartment models, which confirmed the accuracy and the versatility of the program. (A) For the covering abstract see IRRD 863693.

Impact response of thin-walled frame structures

Abstract This paper describes a finite-element method which was developed to predict the impact response of three-dimensional thin-walled frame structures. The softening effect of the load-deformation characteristics for thin-walled beams under combined axial compression, bending and torsional loads during impact is simulated by making use of a nonlinear Maxwell model. The large deformation of a structure is calculated by using updated nodal coordinates and internal forces, and the flexibility matrix for a curved beam element. Crash tests against a flat barrier were made on three-dimensional frame models. Comparisons between the calculated and experimental force-time relations and the deformed shape of the frame are discussed.

Impact response of thin-walled plane frame structures

Abstract A numerical study of the impact response of plane frame structures with thin-walled members was performed to predict the deformation and absorbed energy of automobiles under crash loading. The collapse characteristics of thin-walled members under axial compression or bending loads are considered in the present analysis. The load-displacement relations are given for curved beam members, and the inelastic deformations of members are described in terms of equivalent internal loads and their histories. Crash tests on simplified plane frame models impacted against a flat barrier were performed to verify the proposed method. Numerical analyses were also made of an oblique barrier impact of an automobile underframe structure and a rear end collision of a vehicle structural system. The analytical predictions were compared with the corresponding test results.

Development of an Abdominal Deformation Measuring System for Hybrid III Dummy

In order to evaluate the abdominal injury by using the dummy, a new abdominal deformation measuring system for Hybrid III dummy has been developed. The abdominal compression velocity V, the compression ratio C, and the maximum value of the product VC, can be calculated from the dynamic abdominal deformation of the dummy. This abdominal deformation measuring system consists of an abdominal insert having the same compression characteristics as those of the human body, a dynamic deformation sensor, and an analysis program. This system makes it possible to obtain the abdominal deformation in the impact tests using a cylindrical bar or a lap belt within an error of 10%. SAE Tech Paper 942223 Language: en

Fundamental Study of Dynamic Analysis of Lumbar Vertebrae

This paper describes the results of fundamental study of dynamic analysis of the lumbar vertebrae for the accidental injury. A finite element model with linear brick elements and nonlinear truss elements is constructed for the study of dynamic responses of the fifth and fourth lumbar vertebrae. The results of the analyses show the folio wings: In case of the estimation of the global behavior of vertebrae, it is efficient method to treat the stiff parts of the bone as rigid elements and apply the 8-points integration to the other soft brick elements. To determine the stiffness of ligament for various modeling cases, response surface methodology using design of experiment is applied and the usefulness is verified. And this design of experiment is also applied to examine the influence of the disk properties on the lumbar vertebral stiffness. This bending stiffness of the lumbar vertebrae is rapidly increasing when Poisson’s ratio of nucleus pulposus is very close to 0.5. If Poisson’s ratio is close to 0.5, nucleus pulposus changes its characteristic from compressible to incompressible. In this case, the disk is expected to function as rotator in the extension or flexion of the lumbar vertebrae. To verify this function of rotator, the impact response analyses that dropped block comes into contact with the upper side of the lumbar vertebrae is performed and this function is verified quantitatively.