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We changed only our conception without changing the same level of function and quality as conventional production. We thought about increasing the thickness of the filler pipe face by folding up steel pipe on itself. Through dual pipe forming method, we have achieved our goal of reducing the plate thickness (weight reduction) and supplying the filler pipe without the welding procedure with low cost. Therefore, we applied this techniques to the vehicles of TOYOTA MOTOR Co.,. (refer to Fig.4)

As new component designs for cars become more and more demanding, new technologies or developments are required. Tube Hydroforming technology has been used for many years and new developments can offer potential solutions. The aim of this paper is to show some new developments of this technology for structural automotive components.

Current and future motor vehicle development demands improvement in the areas of economy, environmental acceptability and noise reduction. The performance and manufacture of bevel and hypoid gear sets will also be subject to the same improvement requirements. The above issues will be discussed from a viewpoint of an industrial mass production environment and highlight new developments in gear manufacturing with special emphasis on finish grinding of bevel gear sets. Additionally, new procedures and methods, permitting objective gear quality measurement and noise performance, as well as direct correlation to vehicle performance will be taken under consideration. The integration of manufacturing and test procedures in a closed loop production process will show the best approach to fulfill future OEM demands.

The surface quality of deck face is a major factor affecting the gasket sealing of an engine block. The deck surface quality is mainly governed by external loads (clamping preload and machining force) during machining process. In machining process development, it is highly desirable to predict the quality of a machined surface. The thrust of this study, then, is an attempt to simulate deck face distortion during fixturing and milling operations using finite element analysis. The compliance of fixture components and dynamic response of the fixture-workpiece system are taken into account in this study. Finally, a production v-type engine block is demonstrated.

The inflow of oil mist particles contained in blow-by gas into the intake system worsens emissions. A higher performance oil mist separator system is required to meet emission regulations which will inevitably become stricter in the future. In developing the oil mist separator, however, much of the development time in the past was spent in carrying out repeated tests and studying separator designs. We, therefore, have improved the separator development process by using Computational Fluid Dynamics (CFD) which added several new ideas to improve the analysis accuracy. The comparison of calculated results and experimental results has confirmed that a sufficient accuracy can be obtained to make this method applicable for practical use.

AISI-4140H steel has been used as articulated piston crown material in heavy-duty engines. With the driving force for reducing manufacturing cost, microalloyed steel (MAS) was identified as a low-cost material to replace 4140H steel. In order to determine the feasibility of using MAS to replace 4140H steel, a test program was initiated to fully evaluate the material properties of MAS and to compare them to those of the baseline 4140H steel. The physical and mechanical properties of both materials from room temperature to 550°C were evaluated. The effect of long term thermal exposure on the material properties was also studied. Some engine tests were also conducted to evaluate the performance of the articulated pistons made with both materials. The inherently lower strength of MAS as compared to 4140H steel, requires a total re-design of the piston for the utilization of MAS as a low-cost replacement material for 4140H steel.

Diesel engine operation under high load conditions (>45 hp/cyl) may result in piston “debond” in which the Ni-resist ring carrier separates from the aluminum piston matrix leading to destruction of the piston. Historically, engine loads have increased to achieve higher power densities which together with more stringent emissions requirements have resulted in greatly increased stress levels in the piston. The higher stresses have resulted in debond failure. The design of the ring carrier will affect debond failure. Deformation of the ring carrier will initiate debond at the back of the insert at the junction with the piston matrix. The ring carrier cross-section must be made robust enough through proper design to achieve expected reliability. Another factor influencing ring carrier retention is the quality of the AlFin bond layer. Casting defects which arise from the AlFin bonding process, degrade the strength of the joint leading to failure.

An all aluminum cylinder block with a Metal Matrix Composite (MMC) cylinder bore was developed which made it possible to re-design the base engine for high performance with a bore-to-bore distance as narrow as 5.5mm. The cylinder block is an open deck type and the MMC preform consists of alumina-silica fibers and mulite particles. A laminar flow die cast process was selected to ensure defect-free MMC bore quality. To insure good lubrication, electrochemical machining was applied to the bore surface. By use of radioisotope(RI) measurements, MMC reinforcement was optimized for wear characteristics. Particular attention was paid to use of fuels with high sulfur levels.

DaimlerChrysler and Mechadyne have undertaken a piece of work to investigate the opportunities for improving the operation of light duty diesel engines using variable valve timing. The very high compression ratios used in this type of engine make it essential to be able to alter the valve open periods to affect exhaust valve opening and intake valve closing, whilst leaving the valve motions largely unchanged around overlap top dead centre to avoid valve to piston contact. This paper presents an overview of the design solution, a description of the simulation model used, performance and economy data predicted by the model and a discussion of other areas of opportunity where improvements may be possible.

Commercial Heavy vehicles (CHVs) are an efficient and reliable link between marine, railroad, and air transportation nodes. The vehicle braking power imposes an important constraint in the allowable vehicle speed. The compression brake augments the vehicle retarding power and is currently typically used as an on-off device by experienced drivers. Hardware and software advances allow modulation of the compression brake power through variable valve timing, and thus, enable integration of the compression brake with service brakes. To analyze how much the compression brake affects vehicle speed during braking, we develop a crank angle engine model that describes the intrinsic transient interactions between individual cylinder intake and exhaust gas process, turbocharger dynamics, and vehicle dynamics during combustion and variable brake valve timing. The model is validated using experimental data.

The SI-engine has a disadvantage in fuel economy compared with a DI-Diesel engine. One of the major effects is the throttle-driven load control with its pumping losses. The main target is to reduce these losses in the thermodynamic process with a throttle-free load control. BMW has developed fully variable valve trains as a possible technical solution to realise a load control by regulating the valve lift and the closing time of the inlet valve. The essential variability can be achieved by fully variable mechanical valve trains or mechatronic systems both showing a robust running behavior in emissions and cyclic fluctuations. The camshaft driven mechanical system is based on the technology of the BMW Double-VANOS system. An additional variability makes it possible to shift the valve lift continuously in order to control the valve closing. The highest variability is given by a system with each valve being controlled seperatly.

The increasing complexity of automotive electronic systems can only be managed by a higher integration of the modules and a high reliability of the individual electronic devices. That means, the number of electronic components on board will decrease and their complexity will increase. This paper describes how to meet the requirements for the power supply of a 32-bit microcontroller based system in an automotive environment.

We have applied a non–linear control system to a hydraulically–operated continuous valve timing control (C–VTC) now in the mainstream of variable valve actuation systems. The system applied this time is a sliding mode control (SMC), which is found of late in a number of applications. Hydraulic pressure serving as the driving source of the C–VTC and the mechanism of the C–VTC have non–linear characteristics. We have investigated certain problems which occur, influenced by this non–linearity, when using a PID controller for C–VTC control. Typical issues include a large program memory size because of the large number of control parameters, a resultant considerable number of man–hours required for adaptation, and the low compatibility of response performance both for large step operations and for small step operations. Furthermore, high machining accuracy is required for the mechanical components.

Automotive manufacturers and Electronic Control Unit (ECU) vendors have been struggling with the challenges of providing calibration development capabilities in the mass production intent ECU's while keeping the cost of the mass production ECU's and associated tools to a minimum. Delphi Delco Electronics Systems has been working with Motorola Semiconductor and Infineon to add this capability into new microcontrollers to allow the ECU calibration variables to be monitored and calibration constants to be changed in real-time on the production intent ECU's. This technology has been successfully introduced to ECU customers and has demonstrated a significant savings in tool costs and assisted in improving the accuracy of calibration constant data values.

For basic research on the piston group a new simulation technique is developed using the contact algorithm of a commercial FE-code (MARC). Several improvements were made in order to adapt the MARC solver to the problem of sliding and dynamic contact. The first computations, a real transient analysis simulating the piston group, of both a two-stroke engine and a modern direct injected four-stroke Diesel engine for passenger cars, show that the new method is able to calculate the movements, velocities and accelerations of the piston. The quality of the results is mainly influenced by the hydrodynamic effects.

Today's requirements for engine management controllers are increasing in various aspects. Stronger emission standards and diagnosis requirements demand more complex control algorithms, faster system response times, better usage of sensor information throughout the system and higher accuracy of actuator stimuli. Despite that, new solutions are needed to answer the requirement for higher cost effectiveness, flexibility and reusability. The trade-off between cost and functionality is constantly being reviewed when choosing the right microcontroller to operate with an ECU. Integration of more complex and flexible functionality into the microcontroller helps to reduce the need for custom ASICs and thus reduce the overall system cost. In order to reduce the demands on CPU throughput within the microcontroller, manufacturers have introduced smart peripherals that off-load some of the work of the CPU into the peripherals.

The high temperature tribology issue for uncooled Low Heat Rejection (LHR) diesel engines where the cylinder liner piston ring interface exceeds temperatures of 225°C to 250°C has existed for decades. It is a problem that has persistently prohibited advances in non-watercooled LHR engine development. Though the problem is not specific to non-watercooled LHR diesel engines, it is the topic of this research study for the past two and one half years. In the late 1970s and throughout the 1980s, a tremendous amount of research had been placed upon the development of the LHR diesel engine. LHR engine finite element design and cycle simulation models had been generated. Many of these projected the cylinder liner piston ring top ring reversal (TRR) temperature to exceed 540°C[1]. In order for the LHR diesel to succeed, a tribological solution for these high TRR temperatures had to be developed.

It is estimated that in the United States, nearly one quarter of all fatal automobile accidents involve a vehicle rollover. [1] In order to reduce fatalities and serious injuries, it is desirable to develop a sensing system that can detect an imminent rollover condition with sufficient time to activate occupant safety protection devices. The goals of a Rollover Sensing Module (RSM) are; 1 To accurately estimate vehicle roll and pitch angles 2 To reliably predict in a timely manner an imminent rollover 3 To eliminate false activation of safety devices 4 To function properly during airborne conditions 5 To be as autonomous as possible, not requiring information from other vehicle subsystems.

Due to the increased flight envelope of GV aircraft and the industry-wide problems with crazing of structural acrylic transparencies, a re-design of the Gulfstream cabin windows was undertaken for the GV. The primary goals of this effort were to develop a cabin window that remained condensation free in all operating conditions, had improved service life, retained the size and shape of the classic Gulfstream cabin windows, and met all current FAA and JAA certification requirements. Cost and weight, as well as structural interchangeability with earlier Gulfstream aircraft, were also important issues. These goals were met during a significant design and testing effort undertaken both at Gulfstream and with the vendor, PPG Industries Inc. Aircraft Products. The resulting design, currently installed in all GV aircraft, retains the large field of view that is synonymous with all Gulfstream models while incorporating a number of newer technologies and improvements.

An analysis of vehicle tip stability in NHTSA Side Impact New Car Assessment Program (SINCAP) tests was conducted in order to better understand the causes of possible tip-over in such a test, and the potential relationship to occupant safety. Analyses were conducted of accident data involving light passenger vehicle rollovers. SINCAP tests conducted at several facilities with SUV-type vehicles were reviewed. A computer simulation model of the SINCAP test was developed and used to analyze the effects on vehicle tip-over of variations in vehicle and test facility parameters. It was found that fatal accidents involving “multi-vehicle rollover” (ie, SINCAP like conditions) were the least frequent among four accident types examined; and that SUV’s had the lowest fatality rate in such accidents, among the four vehicle types examined.