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INVOLUTE SPLINES enjoy three major advantages over their straight-sided counterparts: 1. New design concepts have given a more rational approach to clearances and errors. 2. Manufacturing is cheaper and more accurate. 3. Gaging is simpler. Thus, the involute spline standard of SAE and ASA continue to take precedence over the older straight-sided standards.

Wind noise is the sound made as air rushes over a moving vehicle. As other vehicle sound sources are improved, the wind noise becomes the dominant source under certain conditions. The purpose of this paper is to examine the relationship between the properties of wind noise and the human perception of this sound.We find that a particular loudness measure (Zwicker loudness as defined in IS0532B) is the prime factor governing the customer perception of wind noise.

This paper describes an investigation into the sound quality of passenger car and light truck closure sounds. The closure sound events that were studied included side doors, hoods, trunklids, sliding doors, tailgates, liftgates, and fuel filler doors. Binaural recordings were made of the closure sounds and presented to evaluators. Both paired comparison of preference and semantic differential techniques were used to subjectively quantify the sound quality of the acoustic events. Major psychoacoustic characteristics were identified, and objective measures were then derived that were correlated to the subjective evaluation results. Regression analysis was used to formulate models which can quantify customers perceptions of the sounds based on the objectively derived parameters. Many times it was found that the peak loudness level was a primary factor affecting the subjective impression of component quality.

Intake and exhaust valve control has been combined with engine calibration control by an on-board computer to achieve a Variable Displacement Engine with improved BSFC during part throttle operation. The advent of the on-board computer, with its ability to provide integrated algorithms for the fast accurate flexible control of the entire powertrain, has allowed practical application of the valve disabler mechanism. The engine calibration basis and the displacement selection criteria are discussed, as are the fuel economy, emissions and behavior of a research vehicle on selected drive cycles ( Metro, Highway and Steady State ). Additionally, the impact upon vehicle driveability and other related subsystems ( e.g., transmission ) is addressed.

As part of a general EGR system model, an adiabatic thermodynamic vacuum EGR valve actuator model was developed and validated. The long term goal of the work is improved system operation by correctly specifying and allocating EGR system component requirements.

The feasibility of using experimentally determined flow fields at intake valve closing, IVC, as initial conditions for computing the in-cylinder flow dynamics during the compression stroke is demonstrated by means of a computer simulation of the overall approach. A commercial CFD code, STAR-CD, was used for this purpose. The study involved two steps. First, in order to establish a basis for comparison, the in-cylinder flow field throughout the intake and compression strokes, from intake valve opening, IVO, to top dead center, TDC, was computed for a simple engine geometry. Second, experimental initial conditions were simulated by randomly selecting and perturbing a set of velocity vectors from the computed flow field at IVC.

Because it is common to attach plastic parts to other plastic, metal, or ceramic assemblies with mechanical fasteners that are often stronger and stiffer than the plastic with which they are mated, it is important to be able to predict the retention of the fastener in the polymeric component. The ability to predict this information allows engineers to more accurately estimate length of part service life. A study was initiated to understand the behavior of threaded fasteners in bosses molded from engineering thermoplastic resins. The study examined fastening dynamics during and after insertion of the fastener and the effects of friction on the subsequent performance of the resin. Tests were conducted at ambient temperatures over a range of torques and loads using several fixtures that were specially designed for the study. Materials evaluated include modified-polyphenylene ether (M-PPE), polyetherimide (PEI), polybutylene terephthalate (PBT), and polycarbonate (PC).

According to the requirements of high transmission ratio and high load torque of high-speed electric drive axle planetary gear system, the design and analysis of fine-pitch planetary gear system with small modulus, small pressure angle and high full tooth height of are carried out. In order to improve the bearing capacity of gear and reduce gear meshing noise, the tooth profile modification parameters of gear system are optimized. In this paper, the tooth modification methods are analyzed and the gear train parameters are determined. The influence degree of different tooth modification methods on the transmission performance of the gear train is determined by orthogonal experiment method. The transmission error is reduced, the stress fluctuation is improved, and the gear meshing performance is greatly improved by adopting the appropriate modification scheme, which proves the effectiveness of the tooth modification scheme.

The recent development of TiAl-based alloys by the aerospace community has provided an excellent material alternative for hot components in automotive engines. The low density combined with an elevated temperature strength similar to that of Ni-base superalloys make TiAl-based alloys very attractive for exhaust valve applications. Lighter weight valvetrain components improve performance and permit the use of lower valve spring loads which reduce noise and friction and enhance fuel economy. However, difficult fabricability and a perception that TiAl alloys are high cost, low volume aerospace materials must be overcome in order to permit consideration for use in high-volume automotive applications. This paper provides a comparison of properties for several exhaust valve alternative materials. The density of TiAl alloys is lower than Ti alloys with creep and fatigue properties equivalent to IN-751, a current high performance exhaust valve material.

Glass lifter is a key part of automobile door system. Guide rail is the carrier of glass lifter, and it bears various load cases when glass lifer works. Mass, stiffness and natural frequencies are the factors that influence the performance of glass lifter. In order to design a lighter and reasonable glass lifter, topology optimization methods are studied in this paper. In a rope-wheel glass lifter, design domain is determined by the mechanical structure and working conditions. Firstly, the single target continuum structure topology optimization mathematic models of guide rail are built in this paper, and analysis of multi-stiffness topology optimization are carried out accordingly in which volume fraction is set as 0.4, 0.5 and 0.6. These models are based on SIMP (Solid Isotropic Material with Penalization) theory.

When vehicle traveling on the bumpy road or vehicle acceleration and deceleration, which will cause the body vibration of vehicle, at the same time, a large part of energy would be absorbed by the shock absorber transforms the mechanical energy into heat energy dissipated. In order to recycle the energy of vibration and keep the stability of running car, this paper provides the shock absorber of energy recovery that recycling the energy dissipated from the traditional absorber. The shock absorber includes rod and rodless chamber cavity, the two parts contain oil outlet and oil inlet, which connected to a bridge type loop of hydraulic to make pulsating oil pressure towards one direction, when the shock absorber vibration causes pulsating oil pressure, it drives hydraulic pump operation. Because the output shaft of the hydraulic pump fixedly attached to the input shaft of generator, so the generator produces electricity for recycling energy[1].

The salt spray test has been an industry wide standard corrosion test since its conception in 1914. A literary review of its history shows that it has· always been thought of as inconsistent and unreliable but, for a variety of reasons, has continued to be used. A study of more than 55 salt spray cabinets was performed using a controlled lot of parts and questionnaires on cabinet operation. Although the tested parts varied from mildly corroded to extremely rusted no factor could be found to account for the differences. Although the test has its uses it should be studied by an industry formed committee which should make recommendations as to further standardization and corrections to the test. A lengthy chronological bibliography aids the reader in further study and reference.

The Ford Motor Company Advanced Engineering Center contains 100,000 square feet of sound and vibration laboratories, induding full vehicle chassis dynamometers, powertrain dynamometers, and sound quality evaluation chambers. The facility houses the first U.S. All-Wheel-Drive NVH Chassis Dynamometer (4 independent motor drive), the first U.S. All-Wheel-Drive NVH Powertrain Dynamometer (4 independent motor drive) and other unique elements, such as innovative wedge construction for the acoustic chambers.

The evolution and development of the automobile radio antenna is perhaps one of the most neglected success stories in the automotive industry. Born in the twilight of the last century, it evolved from a simple wire wrapped around a tree branch, to the current heated rear screen or backlite antenna. Part One (SAE No. 870090) described seven types of antennas in detail, covering the period 1897-1937. It was shown how the early radio engineers, struggling to develop a viable car antenna, had displayed a great degree of creativity and flexibility, from the “firecracker” experiments of Guglielmo Marconi in 1897, to the ingenious systems developed to overcome the problems created by the all-metal Turret-Top vehicles introduced by General Motors in 1934. In those pioneering days, the United States public was having a love affair with both the automobile and radio broadcasting, so it was no surprise that their marriage did not take long to arrive.

The effect of port injected small fuel droplets was evaluated for several different modes of engine operation. The droplets were generated by an Air Forced Injector (AFI), Figure 1, which uses high velocity air through a nozzle to produce fuel droplets on the order of 10mm Sauter Mean Diameter (SMD). AFI results were compared to those from a standard production pintle injector. Steady state data, “motored cold start” data, and injector cut-out data were collected. All three data sets illustrate functional advantages of AFI over standard Electronic Fuel Injection (EFI). Steady state testing showed that the AFI delivers complete freedom for specifying injection timing with respect to HC emissions. This freedom is highly advantageous for transient conditions because open valve injection with small droplets causes much less port wall wetting. Therefore, less control system compensation is necessary, and more accurate air-fuel ratio control is achievable.

A cylindrical combustion bomb with dynamic charging system and electro-hydraulic sampling valve is used to study the effects of turbulence on hydrocarbon (HC) emissions from a quench layer and from artificial crevices. The turbulence level is varied by changing the delay time between induction of combustible charge and ignition. Propane-air mixtures were studied over an initial pressure range of 150 to 500 kPa and equivalence ratios of 0.7 to 1.4. Sampling valve experiments show that quench-layer fuel hydrocarbons are extensively oxidized within 5 ms of flame arrival under laminar conditions and that turbulence further reduces the already low level. Upper limit estimates of the residual wall layer HC concentration show that residual quench layer hydrocarbons are only a small fraction of the exhaust HC emission.

Based on the technology of the order tracking and extraction, a software for the modulation of sound quality of automotive order sound is developed in this paper. The order analysis, the amplitude modulation of order sound in specific speed range and the calculation of the functional expression of the order sound amplitude are integrated in this software. Furthermore, a side-valve interpolation correction algorithm (SV-ICA) is proposed to solve the problem that the smooth transition of the order sound curve at endpoints cannot be guaranteed, which would result in the appearance of abnormal noise in the modulated sounds. The application of built software in constructing the automobile sounds with the sound quality of sportiness is demonstrated.

This paper describes the major electrical characteristics of the automotive power supply system. It is a compilation of existing data and new information that will be helpful to both the electrical component and electronic assembly designers. Previously available battery/alternator data is organized to be useful to the designer. New dynamic information on battery impedance is displayed along with “cogging” transients, regulation limits and load dump characteristics.

At a time where customer preference is becoming an important product development criteria, measures which quantify subjectively perceived auditory sensations are becoming useful in developing meaningful sound quality criteria. One proposed measure which has not yet seen a great deal of application to automotive sounds is that which attempts to quantify the sensation of roughness. The applicability of such a proposed measure can be established through a series of subjective experiments. Typically, such experiments involve the presentation and evaluation of a group of sounds which vary in their degree of roughness. In order to generate test sounds, a system for the modeling and synthesis of pawertrain sound has been developed which isolates specific signal components which are known to affect the roughness of a sound.

Driveline plunge mechanism dynamics has a significant contribution to the driver's perceivable transient NVH error states and to the transmission shift quality. As it accounts for the pitch or roll movements of the front powerplant and rear drive unit, the plunging joints exhibit resisting force in the fore-aft direction under various driveline torque levels. This paper tackles the difficult task of quantifying the coefficient of static friction and the coefficient of dynamic friction in a simple to use metric as it performs in the vehicle. The comparison of the dynamic friction to the static friction allows for the detection of the occurrence of stick-slip in the slip mechanism; which enables for immediate determination of the performance of the design parameters such as spline geometry, mating parts fit and finish, and lubrication. It also provides a simple format to compare a variety of designs available to the automotive design engineer.