New Concept Modular Manual Transmission Clutch and Flywheel Assembly

<div class="htmlview paragraph">The most common driveline configurations in cars are the standard drive with front longitudinal engine and rear wheel drive and the front-transverse drive with east west installed powertrain as well as all-wheel drive variants derived from these. These driveline configurations are used in different vehicle segments. The transmission systems mainly used today are automatic transmissions with 4 or 5 speeds and manual transmissions with 4, 5 or 6 speeds. A small number of automated manual transmissions (AMT) and continuously variable transmissions (CVT) are in production. Various systems of automated manual transmissions, powershift transmissions designed as double clutch transmissions and toroidal transmissions are currently being developed.</div> <div class="htmlview paragraph">A brief explanation will be given about the structure of all different driveline configurations and the transmission systems will then be considered for specific applications in these different drivelines. The installation situation with transmission structure and space, potential for fuel savings with overall ratio and efficiency, reduction of emissions and noise levels, performance, drive comfort, transmission weight and manufacturing costs are considered as the main aspects within this paper. This leads to an assessment and recommendation for the use of certain transmission systems for the various driveline configurations.</div> <div class="htmlview paragraph">In the future, both 6-speed automatic transmissions and 6-speed manual transmissions will be used on a wider scale with standard drives. The use of continuously variable transmissions will increase for front transverse drive. In the field of manual transmissions the 5-speeds will dominate in front transverse drive applications. The degree of automation will increase in this segment. For torque levels of up to approximately 180 Nm, preference will be given to the use of automated manual transmissions. The range of up to 350 Nm will be predominantly covered by CVT's, five and six-speed automatic transmissions will subsist in the segment above 350 Nm for transverse installation.</div>

Examining drivers injury severity for manual and automatic transmission vehicles-involved crashes: Random parameter mixed logit model with heterogeneity in means and variances

<div class="section abstract"><div class="htmlview paragraph">Automatic transmission (AT) is a complex hydroelectromechanical system, since it consists of hydraulic, electrical and mechanical parts.</div><div class="htmlview paragraph">On cars produced by “UzAuto Motors” mainly AT of the 6T family, 6-speed AT family GM: 6T30, 6T40, 6T45, 6T50 “Hydra-Matic” are used.</div><div class="htmlview paragraph">Production of parts of these transmissions is carried out both at American GM plants and at GM plants in China and Korea.</div><div class="htmlview paragraph">The differences between AT 6T30/6T40/6T45/6T50 are in the thickness of the output chain and in the planetary gear, in the sizes of some other units and the housing itself. But the differences are much more influenced by the settings of the transmission unit, which select operating modes with different engines so as not to overload the thinnest places of the automatic transmission.</div><div class="htmlview paragraph">Automatic transmissions 6T30, 6T40, 6T45, 6T50 have the ability to manually shift gears and activate the “kickdown” mode (for quick acceleration of the car, when you sharply press the gas “all the way” it makes the automatic transmission downshift, and sometimes by two steps).</div><div class="htmlview paragraph">The operation of the transmission is controlled by various electronic systems that are responsible for the operability and structural integrity of the gearbox.</div><div class="htmlview paragraph">Failure of the automatic transmission can occur as a result of one or a combination of malfunctions of the following parts: in the torque converter; in the mechanical part of the gearbox; in the hydraulic part of the control system; one or more clutches of the gearbox; in the electrical part of the control system; in the electronic control unit.</div><div class="htmlview paragraph">The authors of the work investigated and determined the occurrence of malfunctions and failures depending on the temperature of the working fluid of the automatic transmission of a passenger car.</div><div class="htmlview paragraph">Also, the dependence of the resource of the automatic transmission on the temperature of the hydraulic fluid was obtained. High-quality diagnostics of the automatic transmission and its control system can in many cases save the car owner from expensive repairs: <ul class="list disc"><li class="list-item"><div class="htmlview paragraph">without thorough diagnostics, the automatic transmission cannot be subjected to routine or major repairs. Only on the basis of diagnostic information can a conclusion be made about the technical maintenance or repair of the automatic transmission;</div></li><li class="list-item"><div class="htmlview paragraph">based on real experience of operating passenger cars equipped with automatic transmission, we recommend changing the oil every 35000 miles under operating conditions in Tashkent. We also recommend conducting diagnostics of the automatic transmission every 12500 miles of the car's mileage.</div></li></ul></div></div>

<div class="section abstract"><div class="htmlview paragraph">This paper presents a methodology to represent automatic transmission clutch-to-clutch shift dynamics with a two degree of freedom, lumped inertia model. The method of reducing the automatic transmission to a lumped, two inertia model as a function of shift and input shaft acceleration is detailed using a full kinematic representation of the automatic transmission. For a given clutch-to-clutch shift maneuver there are two dependent equations that utilize the two lumped inertias and represent the response of the transmission system from input to output shaft. Applicability of the method is shown for planetary automatic and layshaft dual clutch transmissions. Typical clutch-to-clutch shift maneuvers are illustrated with the two inertia model for power on upshifts and downshifts. The simplification of automatic transmission shift dynamics using this method enables rapid synthesis of a given transmission powerflow for estimation of shift quality potential, required clutching torques, inertia phase engine torque intervention and output torque through all phases of a shift event.</div></div>

<div class="section abstract"><div class="htmlview paragraph">Today turbo-diesel powertrains offering low fuel consumption and good low-end torque comprise a significant fraction of the light-duty vehicle market in Europe. Global CO₂ regulation and customer fuel prices are expected to continue providing pressure for powertrain fuel efficiency. However, regulated emissions for NO</div><div class="htmlview paragraph"> and particulate matter have the potential to further expand the incremental cost of diesel powertrain applications. Vehicle segments with the most cost sensitivity like compacts under 1400 kg weight look for alternatives to meet the CO₂ challenge but maintain an attractive customer offering. In this paper the concepts of downsizing and downspeeding gasoline engines are explored while meeting performance needs through increased BMEP to maintain good driveability and vehicle launch dynamics. A critical enabler for the solution is adoption of gasoline direct injection (GDi) fuel systems. GDi provides the ability to utilize increased scavenging without sacrificing hydrocarbon emissions because fueling and air controls can be separated. In-cylinder injection with GDi also provides charge cooling benefit yielding the knock reduction necessary for turbocharged applications. Several options within GDi are explored including multi-hole and single pintle spray generators, as well as side-mount versus central-mount applications. Both 3-cylinder and 4-cylinder base engine configurations are explored for turbocharged engines downsized to 1.2 L. Improvements in hydrocarbon emissions, heat losses and scavenging favor fewer cylinders. This is re-enforced by packaging and cost considerations. The next system aspect considered is emissions aftertreatment. Stoichiometric turbocharged GDi provides the lowest cost using the established 3-way catalyst. Stratified GDi is expected to require a lean NO</div><div class="htmlview paragraph"> trap (LNT) and diesel Euro 6 systems require addition of a diesel particulate filter (DPF) and possibly NO</div><div class="htmlview paragraph"> aftertreatment. Although the aftertreatment system to meet Euro 6 NO</div><div class="htmlview paragraph"> requirement is not known today, addition of a DPF, DPF with LNT, or DPF with urea selective catalytic reduction (SCR) represent significant cost and packaging challenges. The analysis concludes by comparing the 3-cylinder turbocharged GDi to other offerings in the context of value tradeoff of CO₂ reduction to system on-cost. Stratified 3-cylinder turbocharged GDi systems offer up to 22% CO₂ reduction compared to a baseline port-fuel-injected 4-cylinder engine. CO₂ reduction of 18% is possible for a stoichiometric GDi mechanization that employs variable valve actuation (VVA) and a conventional 3-way catalytic converter. At Euro 6 emission levels, stoichiometric 3-cylinder turbocharged GDi powertrains offer excellent value. The 3-cylinder turbo-diesel offers similar value if it is capable of meeting the NO</div><div class="htmlview paragraph"> emissions standard without lean aftertreatment. Powertrains with higher engine-out NO</div><div class="htmlview paragraph"> levels that require lean aftertreatment are significantly disadvantaged. Based on the price sensitivity of the compact car segment, the value analysis predicts the 3-cylinder turbocharged GDi engine as the powertrain of choice.</div></div>

<div class="htmlview paragraph">Numerical models are described which simulate the wide-open throttle performance of vehicles equipped with either automatic or manual transmissions. Special consideration is given to the initial stages of the simulation including the buildup of engine speed and torque from the idle condition for automatic transmission vehicles and the clutch engagement process for manual transmission vehicles. Tire slip and wheel spin are treated by utilizing a semi-analytical tire model which relates tire slip to tractive force. Lateral weight shifts and effects of tractive effort on road load are also considered.</div>

<div class="section abstract"><div class="htmlview paragraph">The worldwide increasing acceptance and success of modern automatic transmissions in passenger cars is based on innovative technology, driving comfort, shifting dynamic and - most important - fuel consumption reduction.</div><div class="htmlview paragraph">New concepts are facing the challenge of further improvements in internal efficiency and very tough future goals on CO2 emissions in connection with more sophisticated gasoline and diesel engine technologies. Based on the competition and current diversity in automatic transmission concepts, high investments in production facilities must be taken also well into account when thinking about follow-up technologies of installed 8-speed and 9-speed technologies. This must also be considered for the different demands in regions and markets.</div><div class="htmlview paragraph">So, how may a successful automatic transmission system look like in 2020 and beyond? Do we have even more gears than the current 8-speed and 9-speed? Does it make sense to increase the total gear ratio any further? Are there measures to improve the overall mechanical efficiency by several percent? What is the prevailing transmission system: torque converter planetary, dual-clutch countershaft or belt-type stepless transmission? How does the electrification and hybridization of the powertrain in the next years effect the system?</div><div class="htmlview paragraph">This article will give some brief answers on how ZF is planning the future of automatic transmissions and how successful systems should look like.</div></div>

<div class="htmlview paragraph">In undertaking any experimental work the first step is to plan carefully each successive step. Literature bearing on the subject should be examined to learn what work others have done on the problem and avoid needless duplication of effort. If the testing of only a simple accessory is involved, the results the device is intended to accomplish should be studied and an effort made to discover the designer's reason for believing that it will accomplish them. All conditions under which such a device must operate should be listed and the information needed from which to draw conclusions as to whether the device will meet them successfully should be determined. Before starting the actual work of testing, it is good policy to plan the necessary charts for presentation of the report.</div> <div class="htmlview paragraph">This preliminary work means that the investigator will start well prepared but not with his mind made up as to what the results will be. It is necessary to be very careful in all experimental or research work; otherwise preconceived ideas are likely to result in finding what one wants to find rather than the exact truth. Prejudice is not the result of careful thinking and planning but of lack of such forethought. If a problem involves the investigation of a device on an engine, as for example a manifold, it is well to remember that there are other functioning parts and to be on guard against the temptation to attribute a sudden falling off of engine-power to the manifold when it may, in fact, be due to improper functioning of one of the other parts. New problems are more than likely to arise within, the major one as the work progresses and must be solved before the original program can be continued. Each sub-problem should also be planned carefully.</div> <div class="htmlview paragraph">Methods to be followed in making an investigation are elucidated by examples of a study of adapting an existing carbureter to an existing engine and of a study of charge distribution by a manifold to the cylinders of a four-cylinder engine. It is necessary to do this with the use of numerical quantities taken from actual test results, but in the case of the carbureter tests the figures have no actual relation to one another and are not to be taken as representing achievements, as many were taken from experimental engines and other equipment. Before the effect of a given carbureter on the power and fuel economy of an engine can be studied, it is first necessary to learn what the engine is capable of doing when it is not influenced by the characteristics of the carbureter. After charts have been prepared from the ascertained data, the commercial-carbureter tests can be started. Each step for carrying these out is explained. All results are plotted in various ways for comparison and study.</div> <div class="htmlview paragraph">A method that is thought to be easiest and surest for studying charge distribution is by measurement of the maximum explosion-pressures in the several cylinders of a multiple-cylinder engine. The equipment used and the method of doing this are described and the results given. Curves produced from the study indicate that power loss due to poor distribution is incurred by reason of (<i>a</i>) too lean or too rich a mixture and (<i>b</i>) improper spark-advance.</div> <div class="htmlview paragraph">In planning the layout and equipment of a laboratory, a good way to begin is to make a study of the work that probably will have to be done in it and to realize that undoubtedly some problems will have to be undertaken that are not included in the survey, for which reason all equipment should be so designed that changes can be made easily, quickly and cheaply. Known essentials are that</div> <div class="htmlview paragraph"> <ol class="list nostyle"> <li class="list-item"> <span class="li-label">(1)</span> <div class="htmlview paragraph">Equipment must be bolted to the floor</div> </li> <li class="list-item"> <span class="li-label">(2)</span> <div class="htmlview paragraph">Water must be drained away</div> </li> <li class="list-item"> <span class="li-label">(3)</span> <div class="htmlview paragraph">Sufficient working space must be available</div> </li> <li class="list-item"> <span class="li-label">(4)</span> <div class="htmlview paragraph">The entire space must be well lighted</div> </li> <li class="list-item"> <span class="li-label">(5)</span> <div class="htmlview paragraph">The room should have a high ceiling</div> </li> <li class="list-item"> <span class="li-label">(6)</span> <div class="htmlview paragraph">Good crane-transportation should be provided</div> </li> <li class="list-item"> <span class="li-label">(7)</span> <div class="htmlview paragraph">Provision must be made for conducting away exhaust-gas</div> </li> </ol> </div> <div class="htmlview paragraph">A model laboratory that answers all of these requirements is illustrated and described in considerable detail.</div>

<div class="htmlview paragraph">An automatic transmission for heavy duty trucks and buses has been developed. Automatically controlled dry clutch and synchromeshed gear transmission make driving easier, while maintaining good fuel efficiency of a mechanical transmission.</div> <div class="htmlview paragraph">The system consideration and design philosophies of the electronic controller are described here, as well as the mechanical hardware for conversion of a manual transmission into a fully automatic transmission.</div> <div class="htmlview paragraph">This transmission control system has not only the functions of an automatic transmission but also driveability and efficiency same as that of a skilled driver by incorporating various kinds of control logics.</div> <div class="htmlview paragraph">It is our fair judgement that this transmission can well meet market requirements in new age.</div>

<div class="htmlview paragraph">This paper introduces mathematical equations for power loss calculations of major automatic transmission components.</div> <div class="htmlview paragraph">It also presents a theoretical investigation on contributions of each component's power loss to transmission total power losses.</div> <div class="htmlview paragraph">A computer program for automatic transmission efficiency calculation has been developed based on mathematical equations.</div> <div class="htmlview paragraph">Efficiency calculations for the Hyundai A4BF1 electronic 4 speed automatic transmission has been executed in order to validate the program.</div> <div class="htmlview paragraph">The calculated efficiency under various input and operating conditions - such as different input torque & RPM, transmission gear state, ATF temperature, torque converter clutch on/off - showed quite good agreement with the test results.</div>

<div class="htmlview paragraph">There are two major types of problem within the manual transmission system: <ol class="list nostyle"> <li class="list-item"> <span class="li-label">(i)</span> <div class="htmlview paragraph">Gear rattle. The current: solutions are either in the form of spring centre drive plates or twin mass sprung flywheels, both of which suffer from inherent frequency response problems due to their fixed spring torsion rate.</div></li> <li class="list-item"> <span class="li-label">(ii)</span> <div class="htmlview paragraph">Requirements of increased clutch system life when coupled with extended warranty periods and increased power in confined installations.</div></li></ol></div> <div class="htmlview paragraph">This paper outlines the technical advances achieved for a unique combination of products which mark a revolution within the clutch system.</div> <div class="htmlview paragraph">The products consist of a speed sensitive twin mass flywheel which has been designed on the centrifugal link type coupling principle together with a bonded driven plate which utilizes a special elastomer.</div>

<div class="htmlview paragraph">In recent years, progress has been made in reducing the viscosities of manual transmission fluids (MTFs) and automatic transmission fluids (ATFs). Lower viscosities of MTFs and ATFs are expected to improve the fuel economy of automobiles by reducing the viscous resistance. Examples of low-viscosity ATFs already commercially available include Toyota Auto Fluid WS and ZF Friedrichshafen AG's ZNF 13014. This paper first reports methods for measuring the torque transmission efficiency in manual and automatic transmissions. We explain a simple rig test that we developed using an IAE gear test machine, and we describe oil temperature increase tests and torque measurement tests using actual transmissions and fuel economy tests using actual vehicles. Next, we describe the effects of lower viscosities on the torque transfer efficiency as measured with these measurement methods. Because lower viscosities are likely to worsen the wear resistance, extreme-pressure performance, and fatigue resistance of MTFs and ATFs, we studied the effect of the base oil composition and the molecular structure of PMA-based viscosity index improvers (VIIs) on the oil film thickness. We were able to determine by three methods that the film thickness of low viscosity lubricant could be made greater than that of conventional lubricant. The oil film was made thicker in the first method by increasing the molecular weight distribution of the base oil, in the second method by reducing the molecular weight of the PMA-based VIIs, and in the third method by changing the alkyl groups of the polymethacrylate-based (PMA-based) VIIs. The results of our study showed that our optimized lower-viscosity MTF, when evaluated in terms of its wear prevention, extreme-pressure properties, and fatigue prevention, has equal or better performance in each area in comparison with MTFs with conventional viscosities.</div>

<div class="section abstract"><div class="htmlview paragraph">The parameters determining shift quality control in automatic transmissions are determined as part of the calibration of the transmission control. The resulting control system typically has three components: feedforward control, where the control output is determined before a gearshift; feedback control, where the control output is determined during the gearshift based on sensed feedback; and learning control (adaptation), where the feedforward or feedback controller parameters are modified after the current gearshift has ended and before the next similar gearshift begins. Gearshifts involving the same ratio change are referred to here as similar gearshifts, though such gearshifts may involve differences in other variables such as vehicle speed or engine torque. In most automatic transmissions, gearshifts are controlled by hydraulic clutches, and operating conditions for these clutches may vary widely, requiring a dedicated transmission controller involving significant calibration effort.</div><div class="htmlview paragraph">In the current work, novel model-based methods are used to accomplish feedforward control of gearshifts, involving offline calibration of fill and torque phase control parameters and learning control of the fill phase. Towards this end, a physics-based model of the oncoming clutch involved in an upshift of a production automatic transmission was developed and experimentally validated against test bench experiments for a wide variety of inputs and operating conditions. The resulting model is used to generate a feedforward controller, offline model-based calibration algorithm, and a learning controller that corrects for clutch under-fill and over-fill. The effectiveness of the resulting controller is validated by simulation studies using the experimentally validated transmission hydraulic system model, in conjunction with a powertrain model. In particular, it is demonstrated that the learning controller corrects for initial under- or over-fill error in two to three gearshifts. Convergence and robustness properties, and transient performance of the learning controller are also discussed.</div></div>

<div class="htmlview paragraph">The effects of engine operating conditions on the octane requirement and the resulting knock-limited output were studied on a single cylinder engine using production cylinder heads. A 4-valve cylinder head with port deactivation was used to study the effect of fuel octane, inlet air temperature, coolant temperature, air/fuel ratio, compression ratio and exhaust back pressure. The effect of the thermal environment was studied in more detail using separate cooling systems for the cylinder head and engine block on a 2-valve cylinder head.</div> <div class="htmlview paragraph">The results of this study compared closely with results found in the literature even though the engine and/or operating conditions were quite different in many cases. Guidelines on the effect of various parameters on the octane requirement of an engine can be summarized as follows:</div> <div class="htmlview paragraph"> <ul class="list disc"> <li class="list-item"><div class="htmlview paragraph">Spark Advance: 1 ON/1° SA</div></li> <li class="list-item"><div class="htmlview paragraph">Intake Air Temperature: 1 ON/7 K</div></li> <li class="list-item"><div class="htmlview paragraph">Air/Fuel Ratio: peaks at 5% rich of stoichiometric, decreases by around 2 ON / air/fule ratio around peak</div></li> <li class="list-item"><div class="htmlview paragraph">Intake Pressure: 3-4 ON/10 kPa</div></li> <li class="list-item"><div class="htmlview paragraph">Compression Ratio: 5 ON/CR</div></li> <li class="list-item"><div class="htmlview paragraph">Exhaust Back Pressure: 1 ON/30 kPa</div></li> <li class="list-item"><div class="htmlview paragraph">Coolant Temperature: 1 ON/10 K (Similar effect of head and block temperature., Larger effect at low speed.)</div></li> </ul> </div>

<div class="section abstract"><div class="htmlview paragraph">Authors were challenged with a task of developing a full vehicle simulation model, with a target to simulate the electrical system performance and perform digital tests like Battery Charge Balance, in addition to the fuel efficiency estimation. A vehicle is a complicated problem or domain to model, due to the complexities of subsystems. Even more difficult task is to have a control algorithm which controls the vehicle model with the required control signals to follow the test specification. Particularly, simulating the control of a vehicle with a manual transmission is complicated due to many associated control signals (Throttle, Brake and Clutch) and interruptions like gear changes.</div><div class="htmlview paragraph">In this paper, the development of a full vehicle model aimed at the assessment of electrical system performance of the vehicle is discussed in brief. Then, the detailed discussion on the control algorithm which simulates the "driver behavior" for controlling the vehicle model to follow the desired velocity profile as per the selected Drive Cycle. A complete model of a vehicle with manual transmission was developed with all the required subsystems. A feedback and feedforward control algorithm was developed to control the vehicle model. The model was validated by performing a charge balance test on the vehicle's charging system and model predictions were observed to be close to actual test results. The control system developed ensured that the desired speed of the vehicle model is maintained within the tolerance of ± 0.5 to ± 2 Km/hr and executed the gear shifts within 1 second.</div></div>