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This paper presents a new electronic torque split four-wheel-drive system called All-Mode 4WD, which has been adopted in the latest generation of sport-utility vehicles (SUVs). As a torque split system designed specifically for SUV use, it provides stable driving performance matching the driver's intentions under all sorts of operating conditions, from a completely natural on-road driving feel to powerful traction for off-road travel.

Four forces act in rings for a metal pushing V-belt. These forces are: two kinds of intercepting forces which prevent blocks from going outside of pulleys (one caused by pulley thrust, the other caused by centrifugal force), frictional force acting between the rings and the blocks, and bending force in longitudinal direction. In the previous paper (1)(2)(3)(5), distribution of three forces, excluding centrifugal force, were presented at low belt speed. We successfully measured all four kinds of forces including centrifugal force continuously at practical operation conditions for layered rings. In this paper, distribution of these four forces on the innermost ring is described at steady states.

Continuously variable transmissions, commonly known as CVT's, have been shown to be feasible alternatives to the conventional multi-step gear transmissions (standard or automatic) typically used in automotive applications. Most CVT applications, however, rely on a shaft-to-shaft transmission arrangement, in which the belt-sheave action limits the load capacity of the transmission, particularly at the high power ranges (low speed, high torque). In this paper, a system based on a combined planetary gear train and a continuously variable pulley system is presented. The uniqueness of this arrangement is that the variable pulleys provide a power/torque split and recirculation function, which, when combined with the planetary gear train function, produces a continuously variable power split transmission system.

With the introduction of the 5HP24 in early 1996, ZF has completed their product line for 5-speed transmissions. This transmission was especially developed for 8 cylinder engines and has achieved important improvements in fuel consumption, performance, comfort and reliability. This report shows, that 5-speed automatic transmissions result in a reduced fuel consumption, even in countries with speed limits. For example the 5HP24 incorporates the latest developments such as: converter wirth controlled slip clutch (CSC) measures to allow engine speed between 600 and 7200 rpm modern closed loop control shifting strategy performance improved Transmission Control Unit (TCU)

Usage of CVTs in automotive applications has begun to increase, however because of their relative newness and previous usage in nonautomotive applications, a broad base of technical information on the various types of CVT's does not exist. Most importantly though, no comparison information exists on the different types of configurations. Currently, there are a number of CVT technologies that have been used in automotive, off-road and industrial applications. This paper will highlight the characteristics, design limitations and efficiencies of the following basic CVT types:

Life Cycle Assessment (LCA) tools are difficult to handle for designers, especially into the range of a short product development time (eg. from 6 months to 3 years) of complex products like electronic devices and cars: industrialists therefore need more simplified tools for Design for Environment (DFE). That is why Ecobilan, supported by a group of multinational electronic industries, is developing a tool for DFE of complex products, based on a life cycle approach called EIME, for Environmental IMpacts Evaluation. The main differences with a LCA are that an EIME integrates qualitative data into the analysis step and that end of life is tackled through product composition and assembly, but not through end of life modelling. This paper presents the EIME methodology and the EIME tool.

The effects of temperature, crack tip opening rate and rubber content on static fracture characteristics of CNBR (Cross-linked acryloNitrile Butadiene Rubber) modified epoxy adhesives were investigated under mode I loading. Loading-unloading tests were statically performed by using DCB (Double Cantilever Beam) specimens. The fracture toughness increased with increasing the rubber content. The fracture toughness of CNBR modified and unmodified epoxy adhesives was much influenced by temperature and crack tip opening rate. The surface topology of fractured surface was changed by temperature and type of adhesive.

Glass reinforced poly(ethylene terephthalate) polyester molding resins are currently used in various applications for automobiles. These include assemblies such as windshield wiper plenums. Expanding its use into new applications requires that the molded polyester part be able to withstand additional automotive fabrication steps and be tough and dimensionally stable in use. While PET based material is currently used for applications that are affixed to the car body after oven treatment, customers have specifically expressed the need to simplify the automobile assembly sequence by using materials that can withstand the 200°C ovens used to cure car body coatings. Existing commercial grades do not meet all of the additional specific dimensional requirements, although the heat deflection temperature at 1.8 MPa of these types of materials can be well above 200 °C.

Pigmented & mineral-filled PP (PF-PP) is marketed as a potential alternative to ABS for automotive interior applications. However, PF-PP is easily damaged by scratching its surface, thus limiting its acceptance for interior applications. This study investigates the test methods to quantify the extent of scratch & mar damage, and the effect of different mineral fillers towards improving the scratch & mar resistance of PF-PP.

Polyaryletherketones (PAEK) and Polyimides (PI) are increasingly used for demanding tribological applications, especially in automotive powertrains. The parameters that influence the wear rate of these materials are pressure (p), temperature, interfacial velocity (v), counterfacial roughness, component geometry and lubrication. Using the geometry and counterface defined in the testing standard ASTM D 3702, a high velocity comparative study of these high performance engineering polymers was conducted in an attempt to understand the effects of the pressure and velocity combination (pv) on wear rate.

An innovative robotic extrusion technology has been developed by Advanced Elastomer Systems NV/SA (AES) and Gepoc Verfahrenstechnik GmbH in Germany. This technology has proven ideal for producing a soft sealing member on a rigid substrate with a thermoplastic vulcanizate as the soft sealing member. This new robotic extrusion technology will open up a wide range of engineered applications for bonding a soft sealing member to a hard substrate in automotive, construction, appliance and other markets. Potential automotive applications include cowl seals, lighting lens gaskets, and belly pan seals.

Increased awareness of health effects caused by airborne contaminants that include natural and industrial aerosols, bioaerosols and gases, has led to increased usage of various kinds of filters. This trend is reflected in the automotive industry, where cabin air filters are increasingly offered as a means to reduce the likelihood of inhaling these contaminants while driving. Pleated filters, typically employing charge enhanced, thermoplastic base non woven media, have most commonly been applied in order to achieve the requisite level of particle capture, at minimum expense of additional burden to the vehicle HVAC system. The reliability of these filters, however, has been under scrutiny. This is particularly true for those derived from depth electrostatic media. In this study we have evaluated a newly developed depth media, as well as a split fiber electret media, under various simulated environmental and loading conditions.

Despite their high volume of usage, polymers are barely a century old and as such are still a relatively new class of engineering materials. However, plastics are increasingly being used for load-bearing components in demanding thermal, mechanical, and chemical environments. Therefore, the engineering community has a high need to be able to analyze and predict the performance of these materials in order to design parts faster and more accurately. But proper engineering design requires both accurate mechanical properties to define material behavior and effective analysis techniques to predict part performance based on those data. The purpose of this paper is to assess the current effectiveness of materials characterization technology to account for various loading conditions and processing/materials considerations as they relate to material modeling for use in structural analysis.

Between 10- and 11-million scrap vehicles are being recycled each year in the United States by the automotive shredder industry. Presently, they are able to recover 95%of the ferrous and non-ferrous metals in an automobile, which translates to roughly 75% of the total car weight. However, up to 3-million tons of waste, commonly known as fluff or automotive shredder residue (ASR), are generated and landfilled by automotive shredders every year. In order to increase the efficiency of recovery of both ferrous and non-ferrous metals from the shredded vehicles, many new developments have been made in separation technology in the last few years. This paper describes recent developments in shredder downstream separation processes and recycling options for automotive shredder residue.

During injection molding of thermoplastics the filling depends on the material's rheological properties, on the characteristics of the mold and also on the process parameters. Thanks to the elaboration of short shots, it is possible to reconstruct the main successive steps of the filling and to know the advancing melt flow. The choice of specific cavities and particular injection gates allow for filling to be studied in many different cases. The disposition of barriers inside the cavities gives opportunity to orient the flow. Experimental studies consider the injection of polyester and polyamide unfilled and reinforced with short glass fibres. Original results in terms of filling are shown on images. We compare experimental fillings with theoretical fillings obtained with a rheological simulation software. Good agreement is proved for unfilled materials.

In the design phase of aluminum wheels for passenger cars, the wheel's ability to withstand low speed side impacts with minimal damage inflicted to the wheel is of major concern. There are two side impact test standards available today. The one that appears to better simulate an actual wheel-curb impact situation is the SAE J175-88. Part of the test setup includes a deflection check of elastomeric shock absorbers under specified load. The authors have devised a technique to obtain the data for this calibration from a monotonic load/displacement curve. Curve fitting is followed by intercept calculation and a check against specifications. The specified elastomer deflection range under load dictates the expected dynamic response in the actual test. Therefore, in addition to the SAE recommended natural rubber, the authors also investigated the deflection characteristics of alternative polymeric materials, such as EPDM, neoprene and urethane.

Over the last ten years, the plastics industry has been under pressure by many industries, such as automotive, to resolve issues from an application point of view, such as value engineering, part quality, and time to market. Value engineering programs have been a major thrust for the last several years in many industries. These programs have taken the form of low cost materials, systems integration, part weight reduction, and lower fabrication costs. The automotive industry, forced by foreign competition during the 1980s, has also led the way in providing an emphasis toward improved part quality resulting in longer part life cycles. In addition, automotive producers are shortening their design engineering phase which has caused the plastics industry to find methods to more rapidly move technology from research and development to end-use applications.

The amount of carbon and the kind of fixing carbon to supporting structures influences the air permeability and adsorptive efficiencies, which are shown for n-butane, toluene, sulfur dioxide, nitrogen dioxide and ozone.

The performance of the air cleaning filter is important to the long-term performance and reliability of the engine and its components. In this study, the performances of cellulosic and foam filter media for engine air cleaning application are experimentally investigated. Phenolic and non-phenolic cellulose filters were studied. Both flat-sheet and pleated cellulose filters were included. The foams filters were reticulated polyurethane foam media from 20 to 110 pores-per-inch. We measured the initial air flow resistance, the collection efficiency as a function of particle size, and the behavior of dust loading. We also studied the effect of oil treatment on filter performance. The results show that the efficiencies and pressure drops of the cellulose filters increase rapidly with dust loading. Oil treated cellulose filter was found to exhibit slower increases in pressure drop and collection efficiency, resulting in higher dust holding capacity.

The problem of defining mathematical descriptions for instantaneous discharge coefficients of valves and ports for turbocharged engine has been solved. The developed procedure for identification is based on the simultaneous consideration of the mathematical model of the gas-exchange processes and the experimental ‘pressure-crank angle’ histories for the same process. As a result the instantaneous discharge coefficients can be defined by the valve / port geometry, valve lift and pressure ratio. An actual problem for a two-stroke uniflow-scavenged turbocharged engine has been solved. The obtained mathematical descriptions for the discharge coefficient can be used for other engines.