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First introduced in 1995, the concept of a temperature-responsive Variable Orifice Valve to control refrigerant flow (patent # 5,479,786) has been further developed for use in automotive refrigerant systems. This device is an alternative, to the expansion devices currently used in automotive refrigerant systems and offers the best features of a thermal expansion valve system (similar high ambient performance ) and of a fixed orifice tube system (low cost, high reliability & performance at lower ambients). Typical automotive refrigerant system operation includes wide variations in condenser air flow and refrigerant pressure. The resultant condenser exit refrigerant temperature is a very stable input parameter for the control of this variable orifice valve (VOV).

An extensive investigation was conducted to assess the influence of steel sheet surface finish (i.e. topography or “texture”) on painted surface appearance. Ten sets of steel panels representing a variety of shot blast, EDT, laser, and bright surface textures were painted simultaneously using advanced solvent-based luxury vehicle paint systems. Paint appearance was measured using a relatively new Autospect instrument and also in terms of conventional Distinctness of Reflected Image (DOI). The results are discussed in detail with respect to 1) the influence of different steel surface textures on paint appearance, 2) the evolution of surface topography during painting, and 3) the implications of this work.

More stringent Federal Regulations (FMVSS 201 & 208) have been established to limit injuries of car passengers in case of accidents. Materials with good energy management capability, such as Structural Thermoplastic Composites, are being given the first roles in instrument panel, kneebolster and seat applications.

The manufacturing analysis of molded plastic parts is described in detail. A PC based program is presented to analyze the material and capital cost. The program listing is included.

THIS STUDY WAS DEVELOPED in response to a component fatigue strength test which determined that if the current #3 engine bearing cap were used in the 2.5L Turbo application, it would be over stressed. Proposed solutions for solving this problem included: a redesigned grey iron cap with additional material in the highly stressed areas, or a cap made from either nodular iron or a free machining steel using current specifications. One of the manufacturing concerns about switching materials is the perceived difference in the machinability of nodular iron and steel. A single point turning evaluation was carried out by Chrysler Motors' Machinability Development Laboratory to compare the machinability of various materials proposed for use in engine bearing caps. Materials tested included: SAE G2500 grey cast iron, the current production material; SAE D45-12 nodular cast iron; and SAE steel grades 1117, 1137, 1215, 12L14, 1215, and 1215 modified (Incut 200).

Material properties of niobium (Nb)-treated SAE I 141 steel connecting rod produced by control cooling were evaluated in comparison with quenched and tempered connecting rod of the same steel. The microstructure of the control cooled connecting rod is predominantly bainitic compared with tempered martensite for the quenched and tempered rod. Tensile strengths are comparable, while yield strength and ductility are lower for the control cooled connecting rod. There are small variations in hardness of the control cooled connecting rod depending on the section thickness in contrast with the uniform hardness for the quenched and tempered rod. Component high-cycle fatigue resistance is lower for the control cooled connecting rod due to the lower yield strength. Both connecting rods meet the fatigue strength performance requirements for the rod design evaluated.

A new kind of four-speed automatic transaxle, engineered from concept specifically for real-time closed-loop electronic control, has been designed, developed, and put into production by Chrysler Motors Corporation. This overdrive transaxle combines two simple planetary gear sets with five disc-clutches, five hydraulic spool valves, and four direct-acting three-way solenoid valves to achieve all operating modes. It uses no bands and only the torque converter stator has a freewheel element. It provides both a fourth ratio and increased engine torque capacity in the same package space used by the previous three-speed transaxle. At the same time, fewer parts are required and manufacturing is more readily automated.

Process Driven Design yields proven benefits in automotive product design. The use of plastics is expanding in the automotive industry. The designer requires a knowledge of the methods of processing plastic parts. This work provides this information by giving a brief description of plastic processing techniques. Included in this is an extensive table of processing techniques and current parts fabricated by these methods. Extension of the process to future automotive products is included.