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Technical Paper

• Oxidation Stability • Shear Stability • Rubber Swell Properties of Automatic Transmission Fluids

1960-01-01
600048
A NEW TEST is described for studying the oxidation stability of automatic transmission fluids (ATF). The test shows an excellent correlation with transmission oxidation tests and points out the importance of time as a variable in such studies. Carefully controlled automobile dynamometer tests have been used to study the shear stability of ATF's. Data are presented showing a comparison of driving conditions, transmissions, and V.I. improvers on shear stability. Results are related to the 50-hr Hydra-Matic durability test. The poor reproducibility of rubber swell measurements on commercial transmission seals is due largely to differences in the rubber compounds. A great improvement in the reproducibility may be made by taking into account the specific gravity of the rubber sample.*
Technical Paper

“ZYTEL” NYLON RESIN AND “TEFLON” TETRAFLUOROETHYLENE RESIN AS BEARING MATERIALS

1956-01-01
560190
Both “Zytel” nylon resin and “Teflon” tetrafluoro-ethylene resin are being used extensively as bearing materials. Most of these applications have been developed independently and no attempt has been made to collect performance data in order to put future design on a firm basis. Typical data on dry or partially lubricated bearings have been collected from a variety of sources. Work in our laboratories on lubricated bearings made of “Zytel” are reported for the first time. In addition, physical properties of these materials are described. With these properties and the bearing work done to date, it is believed that the selection of the material and the design of bearings can be done with greater accuracy.
Technical Paper

“Virtual Engine/Powertrain/Vehicle” Simulation Tool Solves Complex Interacting System Issues

2003-03-03
2003-01-0372
An integrated simulation tool has been developed, which is applicable to a wide range of design issues. A key feature introduced for the first time by this new tool is that it is truly a single code, with identical handling of engine, powertrain, vehicle, hydraulics, electrical, thermal and control elements. Further, it contains multiple levels of engine models, so that the user can select the appropriate level for the time scale of the problem (e.g. real-time operation). One possible example of such a combined simulation is the present study of engine block vibration in the mounts. The simulation involved a fully coupled model of performance, thermodynamics and combustion, with the dynamics of the cranktrain, engine block and the driveline. It demonstrated the effect of combustion irregularity on engine shaking in the mounts.
Journal Article

“Verify-on-Demand” - A Practical and Scalable Approach for Broadcast Authentication in Vehicle-to-Vehicle Communication

2011-04-12
2011-01-0584
In general for Vehicle-to-Vehicle (V2V) communication, message authentication is performed on every received wireless message by conducting verification for a valid signature, and only messages that have been successfully verified are processed further. In V2V safety communication, there are a large number of vehicles and each vehicle transmits safety messages frequently; therefore the number of received messages per second would be large. Thus authentication of each and every received message, for example based on the IEEE 1609.2 standard, is computationally very expensive and can only be carried out with expensive dedicated cryptographic hardware. An interesting observation is that most of these routine safety messages do not result in driver warnings or control actions since we expect that the safety system would be designed to provide warnings or control actions only when the threat of collision is high.
Technical Paper

“U” Bolt Torque Influence over Leaf Springs

2014-05-07
2014-36-0024
”U” bolts are fixing elements and they are used to clamp an elastic joint. From the past, they still looking as an old design and unfortunately, suspension engineers are not specialists in fasteners and elastic joints. That is why we will show important assumptions and concepts to design and specifications this clamp element “U” bolt and its influence over leaf-springs. Currently, “U” bolt is used to clamp an elastic or elastic-plastic joint of heavy duty suspension, formed by leaf-spring, axle, spring pad, “U” bolt plate. This kind of suspension is typically used to trucks, buses and trailers. We are wondering, which one important assumption that an engineer must be careful when designs a new suspension changing from old designs to an updated technology. We provide a theoretical analysis and a FEA analysis to compare torque efficacy x leaf-spring reactions and what are effects this relationship can cause in a suspension.
Technical Paper

“Symbiose”: Technology Developments for Bioregeneration in Space

1994-06-01
941348
Dedicated technology has been developed to support long-term biological experiments on-board spacecraft. These developments include a microgravity compatible tubular photo bioreactor for the cultivation of micro algae at very high biomass concentrations and with very high gas exchange rates, a microgravity compatible gas / liquid phase separator which also works as a pneumatic low shear-stress pump, a microgravity compatible dehumidifier, and a maltose separating reverse osmosis unit. Integration of these technologies into a partially closed artificial ecosystem form the foundation of the SYMBIOSE concept (System for Microgravity Bioregenerative Support of Experiments).
Technical Paper

“Seizure-Delay” Method for Determining the Seizure Protection of EP Lubricants

1939-01-01
390146
IT does not yet seem to be recognized fully that it is the local temperature at the surface of contact and not the local specific pressure that chiefly determines the occurrence of seizure under extreme-pressure-lubrication conditions. This local temperature is the result of the temperature level of the parts lubricated, considered as a whole (“bulk” temperature) and of a superimposed instantaneous temperature rise (temperature “flash”) which is localized in the surface of contact. It appears typical for extreme-pressure-lubrication conditions, as met in gear practice, that the temperature flash is much higher than the bulk temperature. With existing conventional test methods for the determination of the protection against seizure afforded by EP lubricants, a considerable rise of the bulk temperature mostly occurs; as it cannot be controlled sufficiently; thus, leaving an unknown margin for the temperature flash, it renders impossible a reliable determination.
Technical Paper

“Second-Generation” SAE 5W-30 Passenger Car Engine Oils

1986-10-01
861515
High performance lubricant additive systems have been developed to formulate SAE 5W-30 passenger car engine oils which meet current and anticipated requirements of the North American original equipment manufacturers. The trend in North America is to recommend SAE 5W-30 oils that not only meet the API SF requirements for gasoline engines (“first-generation” oils), but also meet the stringent API CC requirement for light duty diesel engines (“second-generation” oils). Furthermore, the engine builders have issued “world specifications” for motor oils which incorporate additional “second-generation” SAE 5W-30 characteristics, such as enhanced API SF limits, improved fuel efficiency, an increased margin of bearing protection, and lower finished-oil phosphorus levels. The additive systems described herein exceed API SF and CC requirements as well as “second-generation” performance hurdles.
Technical Paper

“Rubber Coupling” at a 4×4 Transmition System

2003-11-18
2003-01-3684
There are many different vibration sources in a car. Engine, gears, road roughness, impacts against the wheels cause vibration and sound that can decrease the parts and the car durability as well as affect drivability, safety and passengers and community comfort. In 4×4 cars, some extra vibration sources are the parts responsible for transmitting the torque and power to the rear wheels. Each of them has their own vibration modes, excited mostly by its imbalance or by the second order engine vibration. The engine vibration is a very well known phenomena and the rear driveshaft is designed not to have any vibration mode in the range of frequencies that the engine works or its second order. The imbalance of a driveshaft is also a design requirement. That means, the acceptable imbalance of the driveshaft is limited to a maximum value.
Technical Paper

“Remanufacturing”: The Sustainable Service Solution for Past Model Automotive Electronics Support

2008-10-20
2008-21-0029
In this paper, remanufacturing will be explored as a feasible option to maintaining the serviceability of electronic modules fitted to vehicles entering their service life from year four (after warranty) and beyond. Understanding the makeup of each module (content, design, and complexity) determines the feasibility of remanufacturing along with its cost effectiveness. Problems exist storing components for many years and engaging in periodic manufacturing is not cost competitive for high content modules. Thus, if reverse capability is not an option, then remanufacturing is a viable solution that, for certain modules, is a cost effective and an environmentally responsible (sustainable) solution to the service parts dilemma.
Technical Paper

“Prediction of In-Cylinder Pressure, Temperature, and Loads Related to the Crank Slider Mechanism of I.C. Engines: A Computational Model”

2003-03-03
2003-01-0728
This paper describes the initial works related to the study of Internal Combustion Engines, as an object of mechanical design, at the Universidad Tecnológica de Pereira. It is reported a concise, complete methodology for simple model of internal combustion engine. The emphasis of the paper is placed on the use of the in-cylinder parameters (pressure and temperature) and inertial loads in the crank-slider mechanism to derive the loads that act on all the components of the crank-slider mechanism as well as the theoretical output torque for a given geometrical structure and inertial properties. These loads can then be used to estimate the preliminary dimensions of engine components in the initial stage of engine development. To obtain the pressure and temperature inside the cylinder, under different operation parameters, such as air fuel ratio and spark angle advance, a Zero dimensional model is applied. The heat transfer from the cylinder and friction are not taken into account.
Technical Paper

“Metallic Core Technology”…and the Production of One Piece, Hollow Composite Components Which Have Complex Internal Geometry

1992-02-01
920507
Engineers have long been restricted in designing and manufacturing one piece, hollow composite components with complex internal geometry. Complex core pulls in the plastic tool, major concessions made in the actual component design or components joined from several pieces were the early means of producing such components. Progressive thinking led to the use of matrix materials such as sand, salt and wax, which provided a measure of flexibility in allowing designed-in undercut areas. These materials, however, lacked the capability to meet the required demands of dimensional accuracy and internal surface, as well as proving themselves unsuitable for high volume production. The concerns for repetitive dimensional accuracy, quality internal surface and high volume production capability has now been satisfied with the use of low melting temperature metal alloys.
Technical Paper

“Mechanical Brake Assist - A Potential New Standard Safety Feature”

1999-03-01
1999-01-0480
This paper presents an innovative brake booster which permits the brake assist function of the electric brake assist system to be implemented with mechanical means. The resultant significant reduction of manufacturing costs enhances the chances for a wide-spread use of this feature in all vehicle classes, thereby making an important contribution to the general improvement of traffic safety. Based on an analysis of the mechanically detectable physical variables for recognizing a panic situation and an evaluation of possible methods of mechanical valve activation, the paper presents a mass production solution and describes its functional properties. In particular, it should be noted that the possibility of controlling the braking pressure within the brake assist function even represents a functional advantage
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