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The automotive industry seeks for lighter components in every new project. Due to strict regulations in CO2 emission and fuel consumption, design engineers are always dealing with huge challenges to manage weight reduction without structural damage for the application and manufacturing processes improvements. The drum brake system is commonly used in compact cars. This system uses two pins and two flat plates to fasten the brake shoe in the drum. A new geometry of anchor pins may contribute to achieve strict targets such as weight reduction, enhance the structural performance and also bring benefits for manufacturing processes. This work presents a new design of a lightweight drum brake anchor pin, which may contribute to the mass reduction through structural, fatigue and metal forming process simulation.

The main characteristics required when fastening racing cars wheel are the resistance to self-loosening plus high-speed to assembling and disassembling of the wheel. To attend these two contradictory characteristics, it is necessary to develop differentiated fastening solutions. This work presents a new concept of fastening central wheel nuts for racing cars with improved fastening efficiency regard safety and assembly speed in comparison to the current fastening. The new wheel nut was designed and validated through analytical and FEM analysis as well as real tests.

The search for more technical and economical competitive automotive products motivates even more the engineers to research for solutions that reduce manufacturing costs and lead-time. Bevel gears are applied extensively in the automotive industry since the invention of the transmission differential, however; few changes of the design have been done on these components in the last decades. Currently, the planetary-bevel gear blanks are hot forged with posterior cutting of the teeth and broaching of the spline, eventually, some planetary-bevel gear blanks have the teeth warm forged. The process to cold forge the teeth and the splines results as much technically benefits for the product application as manufacturing costs and lead-time reductions. This paper presents a planetary-bevel gears manufacturing concept for passenger and light commercial vehicles, where the cold forged teeth and splines present technical and economic benefits to the automotive differential transmission system.

Engine downsizing is the use of a smaller engine in a vehicle that provides the power of a larger one. It is the result of car manufacturers attempting to provide more efficient vehicles by adding modern technologies, for instance, turbochargers, direct injection and variable camshaft. The smaller engine is also lighter and provides torque and power with similar performance to a much larger engine. However, the downsizing technique may lead to undesirable vibration effects on the driveline, such as structural damaging, vibration fatigue failure and extra noise. All these issues are related to natural frequencies investigation and they are often determined through the finite element method together with experimental tests during the product development phase. This work presents the finite element method limitation for natural frequencies determination of automotive components and a possible solution for the issue.

Wheel hubs typically are set in vehicles through nuts with self-locking feature to assure safety. That feature may be done by an external component like a cotter pin, a deformable element incorporated to the nut like polyamide or metallic insert or some controlled mechanical deformation applied right on nut body. Nuts with some self-locking elements are being used in order to eliminate cotter pins from the system. However, during the maintenance of vehicles, some disadvantages appear like damage in thread axle due disassembling, considering controlled mechanical deformation nuts or the replacement of nut with polyamide insert to assure self-lock featuring. This paper presents a solution to replace a fastening in a current front and rear wheel-hub for a passenger vehicle. The study is made comparing a current solution, a controlled mechanical deformed nut - stover type - from a polyamide insert nut and an innovative prevailing torque nut with incorporated washer.

The constant search for more efficient combustion engines with lower levels of CO₂ emissions has contributed to the development of new technologies that could reach severe global environment targets. Most of the new technologies are related to the lift and timing variation of the opening and closing of the intake valves, through variable camshafts. The controlled lift and timing variation allows the air-fuel mixture to be optimized for specific working conditions of the engine without the driver's perception. This paper presents a new design and a new operation concept for the lift variation of the intake valve. The technical and economical feasibility analysis of this new design is done through virtual studies and prototypes in the Alpha phase of the project. The valve lift control optimizes the fuel consumption, and consequently, it reduces the levels of CO₂ emissions.

Traditional propeller shafts using universal joints have been replaced by sophisticated and complex solutions that not only reduce weight, but also increase the performance of such systems in modern automotive vehicles. Due to its complexity that nowadays even may combine plastic and metallic components, traditional analytical models reach their limits to support engineers during their design phase. Particularly, in the case of their analysis under vibration, it becomes critical, as the life time of a propeller shaft and its components (bushes and joints) have to work far away from their natural frequency values. Analytical solutions seem not to be helpful anymore, when one need to reach a mostly precise value of a natural frequency of complex shafts. Although the FEM analysis nowadays is so far highly developed, they are still no responding to the increasingly demand for high accurate results in a short period of development time.

Frictional contact is a recurrent theme in engineering thanks to its ubiquity on several fields of study and the fact it can not be calculated ab initio. Furthermore, it gives rise to other complex phenomena that can only be predicted with the help of numerical methods, like the Finite Element Method (FEM). However, most FEM software still use Coulomb's local model of friction to estimate friction, which may not be reliable on predicting phenomena as complicated as the object of this paper. This work aims to simulate the stick-slip phenomenon in a press-fit and to compare this simulation with laboratory tests. The work was developed based on real cases such as the development of assembled camshafts using tubes. The structural simulations were performed using linear static analysis through the use of finite element method software. Tests were done on a digital torque tester machine used for bolts and nuts. At the end of the work the results obtained in the tests are presented.

CO₂ emission reduction through weight saving remains a huge challenge for all automotive components. When it comes to gears, the state of the art shows low potential of weight reduction due to the trade-off between mass optimization and manufacturing process. Gears are usually forged followed or not by teeth cutting operation. Current presses must operate with a minimum distance between punch and die, due to the elasticity of the equipment, in order to avoid tool failure when it operates with no working piece. Also, the press force is determined by this gap, in cases that some flash is formed during forging, and a minimum flash is required for a forgeable part using the available press. This issue constrains the minimum wall thickness of a final product, for instance, the body of an automotive gear.

This work presents the results of a simulation using the Finite Elements Method (FEM) to study the contact pressure between cams and followers in assembled camshafts. The geometry was chosen based on an iron casting camshaft from a commercial car in order to have a base to ensure that the assembled camshaft is a great solution to increase the performance and to reduce weight. Surfaces that are in contact with high levels of contact pressure can increase the wear and reduce the lifetime of the components. In contact stress analysis, the most critical modeling consideration is to choose the ideal meshing, so, as a preparatory step we summarized with some simulations, defined an acceptable model to run 3D finite elements analysis and calculated the contact pressure.

The guarantee of fastening on assembled joint is still a challenge for the designers, especially regarding the torque loss and consequent loosening of the fastening elements. Among the main reasons of accidents caused by the loosening of these elements, there is the incorrect way to apply the torque on the assembly line (too high or too low) and the possibility of jeopardizing the joint fastening due to vibration acting on the system. This paper presents a solution of fastening where the resistance of the joint loosening is given by the simultaneous application of tensile effort and prevailing torque on the elastic field of the component, which decreases the possibility of self-loosening.

The arrival of new competitors and the continuous growth of the customer requirements, lead the OEM's to reduce the product development time; thus, the simulation tools available on the market became mandatory to the new products development in the automotive industry. However, to simulate a full connecting rod set is very time consuming. The goal of this work is to present the main simplifications that can be set on a connecting rod simulation using the Finite Elements Method (FEM) without jeopardizing the results accuracy. The main contribution of this study is to provide time optimization to the engineers and to avoid a wrong interpretation of the results according to the boundary conditions adopted on the simplified model.

The finite element method (F.E.M.), often known as finite element analysis (F.E.A.) is a design tool based on a numerical process which offers an approximate solution with enough precision for engineering independently how complex the geometry or the actuating loads are. However, the precision is function of many variables and there are some possibilities to jeopardize the result. The most important of all is the stress singularity. The target of this work is to demonstrate the stress singularity problem on a real automotive part and the way to solve it. The main contribution of this theoretical engineering analysis is to avoid a wrong interpretation of the F.E. results during the product development process.

In light of the global trend to reduce CO₂ emissions, the pressure on the automotive industry to further reduce vehicle weights is increasing. Moreover, there is also a need to make more efficient use of the space available, in order to take account of new requirements relating to crash safety and increasing function integration (including dual-clutch transmissions and hybrid applications). When it comes to gears, the differential still offers great potential as regards the reduction of weight and size. This paper will present a new, housing- or cage-less differential that achieves the above-mentioned development goals while keeping to the familiar and tested design principle of the bevel gear set. Simultaneous product and process development and the use of high-precision forging technologies facilitate cost-effective production of this new differential.

The actual needs of weight and CO2 emissions reduction on vehicles stimulate the development of compact and lightweight solutions for new applications. In order to obtain lighter solutions, it is necessary to break some paradigms. The proposal of this work is to demonstrate a method of an effective weight reduction on components of automotive transmissions. The study will be based on the optimization. The goal of this study is to demonstrate clearly and objectively the weight reduction of transmission components without jeopardizing the capacity of the load and the life by fatigue of the component, in other words, without concerns on the functionality and the efficiency of the transmission system as a whole.

High axial loads applied on conical roller bearings can lock the wheel hub after the fastener assembling. This assembly can be made, nowadays, using a castle nut plus a cotter pin or by plastic deformation of the nut to prevent its release. This procedure involves many components for the assembling, restrict its reuse, add extra costs, and provide possible failures during the assembling line or during the future maintenance. This work proposes to demonstrate the development of an efficient and easy system to mount wheel hubs on lines and later to assure maintenance without jeopardizing the efficiency and the functionality of the tapered roller bearing.

The effective length of screwed fasteners, regarding its correlation between safety assembling and production issues, has always been an open question for designers of fastening system. This work presents a real case of dimensioning one wheel nut according to theoretical and practical tests in order to guarantee a safe assembling. The objective of this study is to validate the geometric dimensioning of metric threads and their applications under real conditions.