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Viewing 70801 to 70830 of 110612
1991-11-01
Technical Paper
911305
Z.D. Yan, X.L. Yu, Z.Q. Hu, H.F. Chang, H.Q. Sheng, Z.X. Yin
This paper will summarize the theoretical and experimental achivements in the thermal load studies which have been done, especially determination of the heat exchange boundary conditions, some new methods will be proposed. This made it possible to predict the distributions of the temperature and the heat flux in heated components, when the engine is still in the design stage. Using the aformentional achievements in the thermal load studies, several types of the engines have been designed and developed. Those high speed small air-cooled diesel engines have been successfully applied to the agricultural and industrial multipurpose utilities in the wide area.
1991-11-01
Technical Paper
911306
T. Akaogi, M. Ogura, S. Daidoji
When the exhaust gas turbine diesel engine step in the working range of low speed revolution, the air flow capacity of compressor rapidly reduces, and it become almost unworkable state compared with the ideal super charging condition. It is considered that the effect of gas turbine output power appears sensitively unsuitable condition with the full of gas temperature, pressure, flow volume produced in actual operating gas turbine. In order to correct the effective state produced in lower speed range, the development of movable turbine nozzle vanes equipped with in turbine scroll are being watched with many interests by the reason of requirement. This report mainly concerns itself with authors intend to develop the movable gas turbine nozzle vane and to state the property and actual merit in detail.
1991-11-01
Technical Paper
911303
Bai Jing Sheng, Wang Song Qin, Feng Fu Qiang, Chen Shao Hong, Zhang Dong Sen, Sun Hong, Zhao Jin Cheng, Shi Hong
The key point of reducing idling pollutants from two-stroke engine is to improve gas exchanging quality. This paper proposed a new construction of air-head scavenging project- labyrinth air-head scavenging project. Test results prove that this project together with delaying ignition timing, increasing idling delivery ratio and high-energy ignition can make the idling pollutants of 1E46FM engine reducing from HC> 8000ppm to 5800ppm and CO from 4.8% to <2.0%.
1991-11-01
Technical Paper
911304
Louis H. Browning
Two Computer models were used to study abnormal combustion in a crankcase-scavenged two-stroke engine fueled on methanol. Experimental studies had shown that the octane rating of methanol in this engine was lower than that of gasoline when compared to known reference fuels. Through computer modeling, the abnormal combustion was shown to be a combination of auto and surface ignition resulting from high intake charge temperatures and high residual fractions inherent in crankcase-scavenged two-stroke engines. Precursors of knock were also shown.
1991-11-01
Technical Paper
911309
Jae Cheon Lee
The acoustic attenuator is so highly nonlinear and of high order that the observer design using the linear observer theory can hardly guarantee the robustness against the modeling error and uncertainties. In this paper, a state-space representation of an acoustic attenuator utilizing the electrical analogy is presented first, and the time domain response analysis is performed. The state-space model developed was validated by comparing the simulation results with the experimental results. Then, a nonlinear observer of the attenuator was designed based on the optimization problem which bridges the gap between nonlinear observer theory and its application. The observer performance was evaluated when modeling error existed to verify that the observer designed is insensitive to modeling errors and uncertain parameters. Satisfactory robustness and convergence properties of the observer were found.
1991-11-01
Technical Paper
911310
Peng Jia-Zheng, Hu Ya-Ai
SUMMARY The thesis shows, in details, the study of mixed application of water-blended and idling fuel-saving on an automotive vehicle through the principle of water-blended and idling fuel-saving of an engine, the description of advantages and disadvantages about water-blended and the method for operation.
1991-11-01
Technical Paper
911308
Kiyoyuki Minato, Mieko Iwata
Much attention has been paid in recent years to the enhancement of automobile performance and the improvement of fuel consumption at high speeds. Accordingly, it has become necessary to acquire a precise grasp of automobiles aerodynamic characteristics [1, 2, 3, 4, 5]. Compared with automobiles, however, the general level of interest in the aerodynamic characteristics of snowmobiles has remained low. This relative lack of interest is attributable to the fact that, because the area of the front projection of a snowmobile is comparatively small and the vehicle itself is very light, little emphasis has been placed on fuel economy. Moreover, it is attributable to the facts that improvements in aerodynamic characteristics of snowmobiles do not produce the dramatic effects that they do in automobiles, and finally because of the lack of strong demands in society for such improvement.
1991-11-01
Technical Paper
911314
Toshio Tsutsumi, Makoto Ohtsu
Abstract Motocross (Motorcycle Cross Country), a sport of motorcycle racing held outdoors in rugged natural terrain, was grown in Europe 1960. Then in the later half of the decade, the sport was introduced in the United States as a off-road motor sport as well for leisure. Bringing this outdoor sport of Motocross into baseball stadium, introduced a new sport of indoor Motocross, which is called stadium cross race. This stadium cross the retains showing unmeasurable growth each year world wide and they commonly call a Supercross race. As for supercross racing machine requires high riding technique, which is constituted by durable and high performance racing machines. The engine which is constituted by 2-stroke single cylinder, must be in balance with high power and quick precise response. The suspension system is also a major importance for supercross racing. Landing stability for large jumps, and handling stability for the washboard portions is essential.
1991-11-01
Technical Paper
911311
A.M. Ibrahim, Y.M. Abdel-Rahim, I.G. Ibrahim
A comprehensive investigation of the chemical equilibrium thermodynamic properties (M, CP, h and s) of the products of combustion of ethanol-octane and methanol-octane blends in air is presented. Complete spectrums of fuel blends (ranging from pure octane C8H18 to pure ethanol C2H5 OH or methanol CH3OH), fuel-air mixtures (from very lean, ϕ = 0.15 to very rich, ϕ = 2.0) and combustion products temperature, T and pressure, P (in the ranges of 600-5000 K and .5-1000 ata) are examined. Mole fractions of the most important 16 product species are calculated and discussed. The extent of disscoiation and energy loss terms are defined, evaluated and discussed. The real gas effect on these properties in the low temperature range (600 - 2400 K) when evaluated by correlated equations of Ref. (1)* are found to be insignificant.
1991-11-01
Technical Paper
911312
Hans Holzleltner
Two-stroke racing engines are nowadays in a very high developed stage and are used specially in racing disciplines, where extremly high power to weight ratios are required. But the type of racing sometimes leads to a completely different demand in performance and power band. Two of this contrary applications are Kart and snowmobile racing. This investigation shows, why the demand is so different and what measures on the engines have to be taken, to accomplish this requirements.
1991-11-01
Technical Paper
911290
Katsuhiko Matsuo, Nobuyuki Tani
HST(Hydrostatic Transmission) of BANTAM DUTY series is newly developed compact and general purpose HST. This HST is constituted with axial piston pump & motor of maximum working pressure 14.7MPa has characteristics such as epochal compact, light weight, high efficiency, high reliability, and cost effective. The structure with 6 basic model series of 3 framesize enables it to be used as all kind of small vehicles. In this paper, we explain the basic design concept, technical characteristics of this BD series with applicable cases.
1991-11-01
Technical Paper
911289
Yutaka Furukawa, Eiichiro Ikeda
We have successfully developed a light-loading no-stage variable speed power transmission using V-belt for agricultual and general industrial machines enabling easier manipulation and faster transmission than conventional V-belt transmissions. This paper describes the fundamental operation principle of the transmission, and reports the results of the experimentl studies. The V-belt no-stage transmission is a power transmission which allows the ratio of the revolutions on the input axis to that on the output axis to be controlled with no stage by changeing the winding pitch diameter of a single V-belt put on a variable width (variable speed) pulley. The new transmission we have developed (called VSW-type transmission) is characterized by the linkage of the open/close of driving and driven pulleys with the fundament al principle to reduce operation load during ratio change.
1991-11-01
Technical Paper
911286
A.M. Ibrahim, Y.M. Abdel-Rahim, I.G. Ibrahim
The paper presents approximate formulations for the thermodynamic properties of combustion products of any specified hydrocarbon fuel (CcHhOoNn) in air as functions of fuel type, equivalence ratio, temperature and pressure. Real gas virial equations of state for product species are incorporated in the analysis and their effects are included in the formulations. Results of the paper are compared with other detailed chemical equilibrium calculations for three diverse fuels (octane C8H18, methanol CH3OH and coal CH.17O.05N.02) under different conditions with satisfactorily agreement.
1991-11-01
Technical Paper
911287
Domenico Laforgia
A mono-cylinder engine was built, because of its costs and the semplicity of designing, as flexible prototype. A scavenging system with four ports, two by two simmetrical, was chosen to respect the modern theory of scavenging optimization. The scavenging flow was supplied by a carter-pump; it has been used as first experimental solution. The prototype has been entirely realised and the following experimental measurements have been carried out: the pressure in combustion chamber, in carter pump, in pipes and injection system, as well as the fundamental parameters of engine functioning.
1991-11-01
Technical Paper
911294
Robert Craven, James E. Smith
Balancing to date, of the Stiller-Smith Mechanism, has been for a symmetric configuration. If two pistons are moved closer to the center of the engine to minimize spatial requirements and also reduce weight, then the mass center of the inner mechanism no longer travels in a circle about the center of the engine. It is shown how the overall balancing of the engine is not compromised using the example of a small 8-cylinder engine. The effects of the non-symmetry on the performance of the linear bearing is presented and the resulting additional engineering concerns are discussed.
1991-11-01
Technical Paper
911293
Kazuyuki Shiomi, Hiroshi Mizuguchi
This paper deals with a method of isolating vibration which can be applied to four - stroke, inline, two-cylinder engines with an even firing interval of 360°. This new method effectively isolates 1-st order vibration by positioning engine components and mountings in a way that provides the engine with an oscillation center without the use of additional balancer shafts. The conditions required for the existence of such an engine oscillation center, its movement and the effectiveness of this vibration isolation method are theoretically studied. This method will then be applied to a lawn tractor.
1991-11-01
Technical Paper
911292
Kenji Nishida, Hisao Fukunaga, Kiyoshi Kimura, Yoshimi Osanai
The centrifugal-weight-type V-belt automatic transmission is widely used for the light engines of scooters and agricultural machines, etc. for being compact, efficient and comparatively cheap. The operating section of this centrifugal weight, which contains the metal weight coated with thermoplastic resins in its movable pulley, is lubricated with grease to provide stability and life (reliability) for its operation. However, the grease filling work not only requires a substantial number of man-hours but also various seal parts to prevent, during running, the grease from being splashed about by the centrifugal force and dust particles from intruding. To overcome these restrictions, research has been conducted on how to free the centrifugal weight from the grease by experimenting with various self-lubricant resin compositions as the coating materials for this metal weight.
1991-11-01
Technical Paper
911291
Kichiji Misawa, Tomoaki Ishikawa
The first hydrostatic transmission (HST) installed on a walk - behind lawn mower was introduced 1989. The HST is tiny and efficient. The HST unit weighs 3.1 kg, has a pump displacement of 2 cm3 and a maximum overall efficiency of 72 percent. Since the driving direction is limited to forward, the hydraulic circuit can be simplified. The hydraulic circuit is integrated to the aluminum die-cast transmission case. Operation of both drive and shift levers are converted to the stroke of one single shift cable. This integral operation mechanism enhances such original HST's characteristics as starting with less shock and smooth shifting. Consequently, operational ease of the mower has been drastically upgraded in various locations, especially on inclined surfaces and narrow areas where this type of mower is frequently used.
1991-11-01
Technical Paper
911298
H. Ochiai, K. Hataura
Aluminum radiators using the Nocolok Brazing Process developed by Calsonic Corp. have been mounted on passenger cars since 1985 due to high performance, lightening, and high reliability compared with copper radiators. In this announcement, we will report about the development process of aluminum radiators to achieve weight reduction 30 percent compared with conventional copper radiators and better performance in actual use condition. In application of aluminum radiators by the Nocolok Brazing Process to agricultural machinery, we performed the followings; 1) Evaluation of corrosion resistance (inner, outer) in actual environment. 2) Evaluation of pressure resistance, and vibration resistance in actual working conditions and establishment of optimum mount system. 3) Evaluation of cooling system performance in actual working conditions by using dynamometer.
1991-11-01
Technical Paper
911297
Robert S. Freeland, Fred D. Tompkins, Luther R. Wilhelm, Joe R. Sarten
A tire impact test method was developed to measure the natural frequency of vibration for lawn and garden rear tractor tires. Data from the tests illustrate how a tractor chassis outfitted with a particular set of tires responded after its rear tires were impacted from free-fall. The vertical impact response of four different tire sets are presented. Two commercially-available tire sets vibrated primarily about 4.4 Hz, and to a lesser degree about 72.5 Hz. Two experimental tire sets had a lesser fundamental natural frequency of vibration (3.4 and 3.6 Hz), and also vibrated to a lesser degree about 72.5 Hz. The fundamental natural frequency of the commercial tires fell into the zone where human tolerance to vertical vibration is minimal. The fundamental natural frequency of the two experimental tire sets remained below this zone.
1991-11-01
Technical Paper
911296
Hiroe Nakagawa, Kenkichi Fujii, Mitsuo Yamane
A sealed nickel-zinc battery has been developed to replace the sealed lead-acid battery which was the only battery available for powering an electric undergrowth mower (or a shrub trimmer, or a shrub cutter). The sealed nickel-zinc battery weighs approximately 60% of the weight of the sealed lead-acid battery for a given energy stored, with battery discharge performance at a high current drain, particularly at a low temperature, coupled with a somewhat longer cycling life in a repeated use with a high current drain and charging with a charger exclusively designed for this battery. Unlike the other nickel-zinc battery, this sealed nickel-zinc battery does not use mercury as an additive to the zinc electrode, and so is environmentally benign.
1991-11-01
Technical Paper
911295
Manabu Furubayashi, Naoyuki Soma, Teruo Nakada, Mitsuo Iwahara
The authors developed a new method to calculate engine exciting forces by solving equations of motion using measured angular velocity fluctuation at the flywheel of the engine. Vibration response of a powerplant to the calculated engine exciting forces can be obtained by rigid body frequency response analysis with NASTRAN program using the measured value of the powerplant moment of inertia and the mount rubber characteristics. Calculated acceleration levels of a powerplant by this method were in close agreement with the measured ones. This method can be applied to estimate a powerplant vibration mode and levels when such parameters as engine mount locations are changed. As examples, the effect of reciprocating mass and cylinder-to-cylinder variation of fuel delivery were quantitatively discussed.
1991-11-01
Technical Paper
911302
Debra Sue Creasy, Yukio Ishiuchi, Masaru Fujisaki
There has been an on-going effort to localize Japanese-developed and -manufactured ATV parts in the U.S.A.. In order to achieve this goal, the differences between Japanese and American raw materials, quality control, and production methods were analyzed. The information acquired in each of these areas was utilized to solve the problems created by those differences. As a result, great steps have been taken in the local procurement of ATV parts. Initially, Japanese raw material was investigated. The results of this investigation, coupled with the technical requirements of the axle, were used in the selection of several potential U.S. raw materials. The adopted testing method, “Rotating Beam Bending Fatigue Testing,” was utilized to evaluate and determine which U.S. raw material was best qualified for this application.
1991-11-01
Technical Paper
911301
N. Takahashi, Y. Hiraguchi
Laser welding is frequently applied to process small precision parts since it has high power density and focuses beam spot size smaller. In an automobile industry, the laser welding has been put to practical use for welding of chassis because of its small weld distortion, the other hand, parts of motorcycle which are produced by laser welding are very few. Because most of the chassis and engine are made of aluminum alloys which are difficult to laser weld due to the low absorptivity of aluminum in the wavelength range of commercial laser welding system.(1)* However, the laser welding is applied for a part assembled with press-formed parts. Exhaust Ultimate Power Valve (EXUP), one of the exhaust system for 4-stroke motorcycles which has a precision valve system developed by Yamaha.(2)
1991-11-01
Technical Paper
911299
Kaoru Kito, Kenzo Kawakita, Hiroshi Furukawa
Conventional automotive batteries have been used in agricultural equipment. However, these batteries do not necessarily respond to what the user actually needs. The following complaints are often heard: * Engines do not start after long-term off-season storage. * Inconvenient services, such as recharging, are required. * These heavy batteries have no place to hold on to and is hard to carry. These problems occur simply because regular automotive batteries are applied. To create a truly appropriate battery for this application, some extensive study of actual use of batteries in agricultural equipment have been conducted. A sealed maintenance-free battery that is perfectly suited to this application, requires no service maintenance work, and results in no messy acid leakage was developed.
1991-11-01
Technical Paper
911270
Domenico Laforgia
A new and unique four-stroke i.c. engine without the conventional crankshaft is described. A lobe plate, which moves the piston according to predictable laws of motion, transforms reciprocating movements into rotative ones. The idea derives from the observation of the structure and functioning of pumps with axial plunger whose units plungerod, moving, holds closely to a plate whose angle of inclination determins the motion characteristics and the value of the stroke itself. The new solution introduces a more efficient method of transferring power from a piston to a driveshaft. A peculiar configuration of engine block has been designed, in which pistons, purposely designed, transmit power to a purposely shaped disk. Each piston follows the shape of this disk during the revolutions. The cam provides a broad range of engine displacements using only one block, varying only the piston laws of motion according to the different disks used.
1991-11-01
Technical Paper
911271
Swati Athavale, P.R. Sajanpawar
The paper describes some modelling aspects in finite element analysis of a small four stroke air cooled gasoline engine components subjected to thermal and mechanical loading. The authors have developed parametric model generator for connecting rod using isoparametric element. By discribing parameters numericaly the connecting rod finite element mesh is generated very quickly. It has a provision of inclusion of oil hole model also, which itself is parametric in nature. Authors have developed methodology based on ANSYS Finite element package to introduce inertia loading on connecting rod model. The concept of model generator has been extended for analysis of crankshaft for small gasoline engine. Based on results authors suggest that parametric software must have provision for local refining in finite element formulation so that using submodelling techniques stresses can be predicted accurately after convergence of results.
1991-11-01
Technical Paper
911273
Mutumi Iwasa, Toru Saito
Authors have developed a function that automatically judges the relation among the individual adjoining surfaces constituting the frame body and make a finite-element model of a motorcycle frame body by generating a mesh with all the surfaces together. By integrating this function with the three-dimensional CAD system, a high-speed and simple auto-mesh system has been materialized. This has made it possible to substantially shorten the time required for preparation of a finite-element model and apply CAE at an early stage of design of complicated-shaped constructions.
1991-11-01
Technical Paper
911272
Kunio Noda, Nobushige Anzai, Manabu Furubayashi
Several techniques have thus far been scrutinized for the estimation of machine vibration originated with the engine. Nevertheless, there has existed no other way available than to conduct experiments to know the vibration level quantitatively, since such techniques available today are not accurate enough. Authors have thus pursued research and succeeded in working out a simulation method that is capable of estimating, at design stage, the vibration attributable to engine exciting force on machine structure, especially on the low frequency vibration, that in consequence caused the oft-occurrence of problems such as noise through the vibroaction of panels, as the engine is mounted on the vehicle frame via mounting rubbers. Authors then applied such method to selective engine mounts and validated a good agreement with the results obtained from the simulation and the life-test, even with the use of mount rubbers of varying characteristics.
1991-11-01
Technical Paper
911274
Yoshihiko Kawazoe, Shiping Zhang
It is the aim of this presentation to deal with an improved transfer matrix method for three dimensional vibration analysis of a reciprocating engine crankshaft system, so as to provide an efficient and convenient method for complex crankshaft system dynamic analysis. For different type of crankshafts, only the numbers and relative direction angles of the cylinders are required as input data besides the structural data. The theoretically predicted frequencies and mode shape agree well with the experimental results. In the case of dealt with a four-cylinder two-stroke small engine, five times exciting forces are of the most important which induce the crankshaft resonance. An effective and convenient general computer program for disign engineer to operate has been developed.