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In the engine management systems field, there is lack of sensors locally built and available for sale in Brazil. Therefore, many auto parts companies have to import them affecting directly the final products costs (technology know-how/development costs, import taxes and other material handling/custom related costs). This paper was motivated to study an alternative for a simple, cheaper and locally made throttle position sensor. The choose of this part was because the fact that it is one of the most expensive in the throttle body bill of. For developing this new alternative, it was used a tool called value analysis and value engineering. The outcome of this study was a throttle position sensor function integrated to the throttle body manufacturing line with the advantages that 100% components can be locally purchased, improved robustness against humidity and component quantity reduction by 40%. Therefore achieving more value added.

The penetration of rainwater through the heating ventilation and air conditioning system (HVAC) of a vehicle directly affects the provision of thermal comfort within the vehicle passenger compartment. Present vehicle designs restrict considerably the air-management processes due to reduced space and tighter packaging. The motivation for the study is to get an insight into factors affecting the water ingress phenomenon when a stationary vehicle is subjected to water loading such as heavy rain when parked or waiting in a traffic light or when in a car wash. The test programme made use of a compact closed circuit full-scale automotive climatic wind tunnel that is able to simulate wind, rain and road inclination. The tunnel was developed as part of the collaborative research between the Flow Diagnostics Laboratory (FDL) of the University of Nottingham and Visteon Climate Control Systems [1].

The drive to reduce weight, simplify assembly, and cut total system cost in today's vehicles is relentless. Replacing metal systems with thermoplastics has been of considerable interest in the engineering community. The current generations of engineering thermoplastic resins are enabling the use of plastic systems in demanding underhood applications. Technical data and discussion regarding the materials, design, molding, and assembly of lightweight composite throttle bodies will be presented in this paper. Comparisons with machined aluminum throttle housings are drawn to establish a baseline with the throttle body housing component that is most common in production today. Design flexibility and process simplification are some of the approaches highlighted. Much of the technical information provided in the paper applies to both cable driven mechanical throttle bodies as well as electronic throttle bodies under development.

For the past decade or so, automotive entertainment subsystem architectures have consisted of a simple Human Machine Interface (HMI), AM-FM tuner, a tape deck, an amplifier and a set of speakers. Over time, as customer demand for more entertainment features increased, automotive entertainment integrators made room for new features by allowing for the vertical integration of analog audio and adding a digital control. The new digital control came to entertainment subsystems via a low-speed multiplexing scheme embedded into the entertainment subsystem components, allowing remote control of these new features. New features were typically incorporated into the entertainment subsystem by independently packaging functional modules. Examples of these modules are cellular telephone, Compact Disc Jockey (CDJ), rear-seat entertainment, Satellite Digital Audio Radio System (S-DARS) receiver, voice and navigation with its associated display and hardware.

The established method of clearing a misted car windshield or of maintaining a clear view under misting conditions is through the application of an air supply via jet outlets in the instrument panel. The ability of such arrangements to perform adequately is a function of the prevailing environmental conditions, the vehicle speed, the condition of the demist air source and the geometry and arrangement of the jet outlets. This paper presents experimental data obtained in a purpose built environmental chamber designed to accommodate simple rectangular jets impinging on a misted glass surface. The facility consists of three conditioned air sources applied to a test chamber designed to represent the external, internal and demist air flows. Mist conditions on the glass surface are determined using a novel technique employing a CCD camera acquiring grey scale images which are digitally analysed to generate mist detection, grading and clearing contour data.

Environmental concerns have spawned renewed interest in naturally occurring refrigerants such as carbon dioxide. CO2 has attractive features such as high enthalpy of evaporation and low cost compared to halocarbons. However, the vapor pressure of CO2 is high at temperatures normally encountered in refrigeration and air conditioning systems when compared to traditional and alternative refrigerants such as CFC-12 and HFC-134a. Major research efforts are underway to investigate the transcritical CO2 cycle, in which a gas cooler instead of a condenser accomplishes heat rejection to ambient, since carbon dioxide in this cycle is above the critical point. The vapor pressure in the gas cooler may exceed 120 bar (1,740 lb/in2). In this paper a reduced pressure carbon dioxide system is revisited1, 2. The working fluid is a mixture of CO2 and a non-volatile liquid, referred to as a co-fluid, in which CO2 is highly soluble and readily absorbed and desorbed.

Desiccant materials are commonly used in the automotive industry to reduce the level of moisture in vehicle air conditioning systems. The primary purpose for removing moisture from these systems is to avoid corrosion of metals, compatibility problems with polymeric materials, and possible freeze-up associated with free water. In nonpolar R-12/mineral oil systems with low solubility for water, moisture levels are usually controlled to 25 ppm or less. However, R-134a and PAG are highly polar and have good solubility for moisture, thus presenting reduced risk of free water in the air-conditioning systems. This paper addresses the questions of whether desiccants are required in air conditioning systems using R- 134a/PAG, and if required, what is the optimum quantity of desiccant for system stability and long-term system reliability Tests were conducted in the laboratory (accelerated sealed tube aging according to ASHRAE standard 97- 1989) as well as in the field (vehicle fleet tests).

Pressures to increase the recyclable and recycled content of passenger vehicles are accelerating. In Europe, there is interest in eliminating halogenated polymers. Globally, more and more concern is focused on materials and methods that are ecologically friendly. Automakers and their suppliers are being encouraged to design and assemble components in new ways to facilitate separation, identification, and resource recovery at the end of the vehicle’s useful life - something that is not only good for the environment, but also the bottom line. One area of the vehicle that has proved challenging for applying such design for disassembly and recycling (DFD/R) principles has been the interior, owing to the sheer number of materials used there, and the great number of laminate structures that make disassembly nearly impossible. A good example is a door panel inner, which typically consists of a rigid plastic substrate, a foam pad, and a vinyl, leather, or cloth covering.

This paper will discuss the analysis of a high-heat, unfilled polyetherimide (PEI) thermoplastic in a complex reflector application with conventional aim (bubble-vial) beam pattern. The advantages and disadvantages of using PEI thermoplastic vs. bulk molding compound (BMC) in a complex reflector will be presented. Design features, testing methodology, and processing techniques for the use of PEI in such applications will also be highlighted.

Environmental concerns have spawned renewed interest in naturally occurring refrigerants such as carbon dioxide. CO2 has attractive features such as high enthalpy of evaporation and low cost compared to halocarbons. However, the vapor pressure of CO2 is high at temperatures normally encountered in refrigeration and air conditioning systems when compared to traditional and alternative refrigerants such as CFC-12 and HFC-134a. Major research efforts are underway to investigate the transcritical CO2 cycle, in which a gas cooler instead of a condenser accomplishes heat rejection to ambient, since carbon dioxide under these conditions is above the critical point. The vapor pressure in the gas cooler may exceed 120 bar (1,740 lb/in2). In this paper a reduced pressure carbon dioxide system is reported (Ref 1). Two companion papers will address properties of working fluids (Ref 2) and thermodynamic and cycle models (Ref 3) for the low pressure carbon dioxide cycle.

Damage to painted automotive plastics induced by Hertzian contact stresses continues to plague the material engineer involved in the design and selection of fascias, bumpers, body-side moldings, and the like. Studies conducted to determine the root cause of such failures have focused on the effects of paint and the role of friction in the compressive, tensile and shear failure of painted thermoplastic olefins (TPOs). The study described herein probes the effects of paint type on the compressive, tensile and shear damage resistance of painted TPO substrates. Coating variations, e.g., adhesion promoter and topcoat type, and their effect on damage type and damage sensitivity will be described. The apparatus utilized to impart the damage, SLIDO, and the variables studied affecting the damage, e.g., acceleration, velocity, temperature, and loading pressure, are also discussed.

Fuel Vapor Storage Systems (FVSS) on automobiles are susceptible to particle contamination. This is especially true for FVSS components mounted under the automobiles (undercarriage, chassis frame, etc.) and required to meet stringent EPA standards. Particle contamination significantly increases system restriction and reduces the effectiveness of FVSS. This paper describes a dust separator/filter developed to protect the FVSS. Accelerated field durability evaluations and measurement techniques were developed to identify clean locations, ingested contamination levels and ingested contaminant size distributions. Based on field evaluations, test methods were developed in the lab to evaluate effectiveness of several devices to control and reduce contamination. The dust separator design developed was a combination of baffle separators in series with an open cell foam filter. The dust separator was designed to meet and exceed several vehicle system design requirements.

A compact cassette and compact disc (CD) mechanism mounting bracket was developed for an automotive radio. The bracket, a single die cast magnesium component, offers a light weight, rigid platform for simultaneously attaching both mechanisms to create a simple modular subassembly.