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This paper details an analysis theory to simulate various dynamic characteristics of a windshield wiper system on a vehicle for the purposes of computer-aided virtual prototyping. The analytical model consists of three-dimensional (3D) mechanical models of the complete wiper system and arm & blade subsystem which carries out complex reversal behavior. The equations of motion are solved considering the vehicle's 3D windshield surface data. Thus, the dynamic reaction forces in the vertical and frictional directions can be calculated at any point within the wiping pattern.

As automobiles become quieter, wiper operation noise becomes more noticeable. Squeal noise is one type of wiper operation noise. It is a high-frequency self-excited vibration that is easily generated before and after the wiper reverses direction. In analyzing this vibration, squeal noise was observed using a rotary disk system. Then FEM was applied to deduce an equation of motion that reflects the observation results. The equation suggests material and configuration approaches toward reducing squeal noise. Potential measures include improvement in the blade damping coefficient, reduction in the coefficient of friction by surface treatment, and an increase in neck thickness, etc. Implementation of these measures reduced squeal noise.

The blade impact force at the top and bottom reversal points contributes significantly to wiper system noise. This paper describes a newly developed process to simulate blade reversal behavior. The results of this simulation can provide necessary insight into reducing blade reversal noise. As a result of simulation under various conditions, it is shown that the reversal impact force can be reduced by modifying the maximum rubber neck rotational angle and the rubber neck rotational spring constant. It is also shown that the reaction force at the top and bottom reversal points can be adjusted by modifying the arm head twist angle.

When a motorcycle runs with hands free riding, the change of the handle deflection angle is interlocked with the vehicle body (frame) bank angle, which is operated by the rider lean angle and caused by the disturbance of road surface. In this report, the motion of the rider who maintains the upright stability of a motorcycle in hands free and hold grips running at low speeds was studied from the experiment with measuring the vehicle frame bank angle, the rider's lean angle and the handle deflection angle, and the rider's feeling evaluation concerning the stability.

This paper will focus on fuel flow analysis in nozzles, in particular, in the injection hole, a key component of Fuel Injection Equipment(FIE). Optimum controlled flow in the hole improves flow efficiency and atomization. To meet the emission regulations which will be introduced from the end of '90's to the 21st century, Diesel Engines require FIE to produce higher injection pressure which creates better atomization and higher utilization of air. But higher injection pressure results in increased pump driving torque, larger pump size and higher cost. We have studied the improvement in fuel flow characteristics of the nozzle, using an enlarged flow model and the theoretical analysis method. As a result, we have found that the cavitation, which occurs at the inlet of the hole, is affected by the configuration of the sac hole and injection hole. And, furthermore, the cavitation has a direct effect on the contraction and its recovery flow.

This paper describes the self-excited brush vibrations which induce chirp noises in the permanent-magnet direct-current blower motors (150 W) used in automobile air-conditioners. Based on regeneration of the brush noises and analysis of the brush vibration measurements, we can distinguish two types of brush vibration: one is a high frequency mode, 10 - 20 kHz, which results from coupling the pitching mode and the radial-direction mode of brush; the other is a low frequency mode of the brush which vibrates together with the insulator disk holding the two brushes, 1 - 5 kHz, which results from coupling the yawing mode and the rolling mode. Dynamic models of these two types of vibration and the motion equations are constructed by analyzing the brush vibration measurements, and the mechanisms of generation are confirmed by the eigenvalues and eigenvectors obtained from the motion equations.

The purpose of this study is to make clear the relationship between flow characteristics in the nozzle and injected spray characteristics. In this paper, we discuss the effect of the sac volume in the standard hole type nozzle on fuel flow and spray. The main object of this paper is to analyze fuel flow characteristics in the nozzle by using the enlarged model nozzles. Spray investigations confirmed that reducing the sac volume causes changes in the fuel injection direction at the initial stage of injection and in the spray penetration over consecutive injection. Flow investigations in the injection hole clarified that meandering the flow in the hole causes changes in the fuel injection direction. Flow investigations in the sac chamber clarified that separating the flow from the sac wall causes meandering the flow in the hole. Furthermore, the methods to restrain the flow in the sac chamber from separating from the sac wall were discussed.

This paper reports on research conducted at Nippondenso Co., Ltd. and Meiji University on nozzles for heavy duty diesel engines. It focuses on fuel flow analysis in the nozzle, a key component of Fuel Injection Systems (FIS). The optimum design nozzle improves fuel flow and spray characteristics. A newer and tougher emission regulation from the EPA for heavy duty diesel engines will be inevitable from 1998 onward. The goal of every company is to design new FIS in advance which meet the regulations of the future rather than paying for expensive developing costs after new laws have come into effect. To meet the regulation, requirements for FIS are higher injection pressure and injection rate control which create better fuel spray atomization and higher utilization of air. In particular, the nozzle must ensure that high injection pressure is effectively converted to fuel spray without pressure losses.