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Mitsubishi has developed the new, compact, water-cooled vertical type 2-cylinder diesel engine model K2AS and brought it to market in spring of '82. The K2AS is a small-sized engine of 451 cc total displacement and 10HP/3600 rpm maximum output. Its weight of 58 kg is light enough to use this diesel engine for various machines which have formerly been driven by gasoline engines. The well matched combustion chamber and injection system realize low fuel consumption, low noise and easy engine starting. High durability is also assured by various kinds of reliability evaluation. Features of K2AS are outlined below.

To date there is no universal agreement as to the interaction between fuel type, fuel-air mixture preparation and combustion chamber flow characteristics and their effect on soot formation. A propane fueled modified conical back-mixed steady flow reactor was built in which the fuel and air could be mixed together in varying degrees and reacted in at different mixing intensities. The onset of soot and soot loading were determined qualitatively by a photomultiplier focused on the volume inside the reactor. Increasing the degree of premix from a diffusion flame to a distribution of Φmax/Φavg = 5.0 resulted in increases of 3 to 17 percent of the soot-onset equivalence ratio and decreases in soot loading down to zero. Changes in the mixing intensity from 32.5 sec−1 to 75.7 sec−1 resulted in a change in the soot-onset equivalence ratio from 1.26 to 1.52. Soot loading was found to depend on both the mixing intensity, β, and the average number of mixes per mean residence time, β/α.

A new combustion system for a light duty D.I. diesel engine was developed, and a 3.5 ton payload truck (6.5 ton G.V.W.) equipped with this D.I. diesel engine and this combustion system realized good fuel economy and lower exhaust gas emission. Generally, light duty vehicles have to operate over a wide engine speed range. Therefore application of a D.I. diesel engine to light duty vehicles is difficult because of combustion tuning requirements over a wide engine speed range. Up to now, most of the diesel engines for light vehicles have been of the I.D.I. type. But the D.I. diesel engine has an evident advantage of lower fuel consumption. In these circumstances the authors developed a new combustion chamber shape for a small D.I. diesel engine with turbulence induced intake port and optimum fuel injection equipment. Various combustion chamber geometries were tested and evaluated.

A DI diesel engine with an air cell was developed as one of the combustion systems for reducing soot emission from diesel engines: The air is accumulated in the air cell during the compression stroke and is injected into the main chamber during a period after the end of injection. The air jet stirs the stagnant flame and promotes soot oxidation. A comparative experiments with the conventional system made it clear that the air-cell system effectively reduces soot emission at a medium and high load condition.

A new hydraulic cylinder has been designed and tested which improves the cylinder operating characteristics. This cylinder uses state of the art seals at pressures of up to 5000 psi that reduce friction by 10 to 25 percent and eliminate “stick-slip”. Application of this type cylinder can greatly reduce hydraulic system size and cost to the OEM, as well as reduce energy cost to the end user of the equipment.

This paper describes a method to determine control losses, i.e., losses solely due to regulation of velocity of the load, for various variable pump systems as compared to conventional fixed pump-open center, by-pass valve systems. The method is graphically illustrated in load pressure-flow diagrams where the different control losses are shown. Loci of comparative control losses are plotted in the load pressure-flow diagram and if the pressure-flow-time duty cycle is known, the total difference in control energy loss/duty cycle can be computed for a particular machine. This energy loss is then converted to the difference (gain or loss) in fuel consumption and cooling requirements. Finally, results from test runs with a backhoe-loader and three different operators are shown.

MEDIUM DUTY MOBILE EQUIPMENT CAN REALIZE PRODUCTIVITY GAINS THROUGH THE APPLICATION OF SERVO CONTROLLED HYDROSTATIC TRANSMISSIONS. TO ACHIEVE THESE GAINS, HYDROSTATIC TRANSMISSIONS FOR MEDIUM DUTY VEHICLES MUST POSSESS DESIGN FEATURES WHICH PROMOTE MANAGEMENT OF DRIVELINE EFFICIENCY. HOWEVER, TO ACHIEVE COMPATIBILITY WITH THE MEDIUM DUTY VEHICLE, THESE TRANSMISSIONS SHOULD BE DESIGNED WITH THE COST, LIFE, AND SIZE GOALS OF MEDIUM DUTY IN MIND. THIS PAPER PROVIDES DEFINITION OF THE MEDIUM DUTY CONCEPT AS IT PERTAINS TO HYDROSTATIC TRANSMISSION APPLICATION AND DESIGN. EXAMPLES OF THE POTENTIAL FOR PRODUCTIVITY ENHANCEMENT THROUGH THE USE OF MEDIUM DUTY HYDROSTATIC TRANSMISSIONS WITH INTEGRATED SERVO CONTROL ARE PRESENTED.

The John Deere cam lobe motor introduced two years ago has found primary usage as auxiliary drive systems on harvesting machines. The performance and reliability have been well received on John Deere combines and forage harvesters and in some OEM applications. The basic family is now being expanded to provide new features and flexibility for the OEM market. The expansion to include fixed as well as steerable mountings, shiftable operation (1, 2 or 3 speeds), greater axle capacity and an optional brake will be described. The challenge of extending motor capability and flexibility while minimizing total number of family components and maintaining reliability will be addressed.

To match the increasing demand of the market for high torque, low speed motors, Poclain Hydraulics applied its vast experience and know-how to develop a new range of small piston motors to fit the low horsepower applications. The modular concept, the high efficiency and the high pressure capability of this new product, we believe, will contribute to further develop the low speed motor market.

Predicting the trends which will impact agricultural technology in the next decade is surrounded by a degree of uncertainty. The broad long-term trends of population growth, food demand, developing technology and resource depletion can be predicted. Economic recessions and international crises are less predictable. All of these factors affect the generation and adoption of new agricultural technology. Other factors affecting agricultural technology include economics at the farm level, energy availability/cost and the types of crops grown. Computer technology and educated farm managers will have an influence on the adoption of still other technology. Taxes, cost of labor, cost of land, demand for agricultural products, electronic sensors and innovativeness in manufacturing and on the farm will all influence agricultural technology and its adoption.

During the next ten years the United States will experience a change in farm structure. A smaller number of farms will be producing more food. Both very small and very large farms will increase in numbers. They will change to be more diversified in production, utilize on-farm processing of consumer products, and apply advances in automation. These changes are needed to provide consumers food that is cost and quality competitive in worldwide markets. This paper is intended to instill the reader into becoming aware of the changes in technology, marketing, banking, labor and population interests. These trends will direct new farm mechanization towards intelligent machines capable of doing a multitude of tasks. Advances in vision systems, lasers, speech recognition, and bubble memory will be incorporated into mechanized robots and controlled traffic systems. In no way is this paper to be construde as a forecast because the direction of technology can not be forecasted.

The latest innovations in coordinate measuring machines and instrumentation have been combined with theoretical gear calculations to provide an objective quantitative method for inspecting bevel and hypoid gears. The measuring machine, its software, the gear software and the measuring procedure are described. Also included is an example of the use of the procedure in the development of a gear set.

Groundwater supplies throughout the United States are threatened by migration of contaminants from numerous sources including solid, chemical and hazardous waste sites. Complete isolation of these sources and their corresponding high concentration migrating plumes is a major step in mitigating the danger of groundwater contamination and is often a cost-effective step in the cleanup process. The “Block Displacement” technique has been developed for complete isolation of large tracks of contaminated ground. A full-scale demonstration was recently conducted on a 50,000 ft3 block of unconsolidated soil. The technique places an impermeable barrier around and beneath the contaminated zone. In the process, the ground is physically displaced upward by multiple well injection of a barrier material in a slurry state.

Over the past twenty years a number of companies have developed proprietary processes for forging net shape straight bevel gears. The inherent complexity of bevel gear geometry requires tight process control to forge gears which require no further machining on the teeth. Electrode design, die manufacture, scale control and finish machining are critical areas which require special attention to obtain functional gears with integrally forged teeth. Gears with integrally forged teeth have inherent advantages over conventionally manufactured gears. These advantages include improved strength, less raw material, design flexibility and cost savings. Examples of these benefits are discussed.

THE POWDER METALLURGY PROCESS for producing gears is one of the most flexible metal working techniques available today. By adding elemental powders to the base powdered material, the chemistry can be tailored to achieve mechanical properties ranging in strengths from 20,000 P.S.I. to 160,000 P.S.I. . The process is capable of producing close tolerance gears in high volume at extremely economical prices.

A computer-aided technique is being developed for planning, design, estimating, and scheduling of horizontal construction for facilities required to support military operations. This technique permits the user to quickly analyze possible sites and identify those which would require the least construction effort. Once the user selects the site for a facility, the system can design the earthwork, quantify estimates of each earthmoving function, and generate a construction schedule. The user can choose whether the schedule is to be equipment constrained or completion time constrained. This paper describes the technique, including discussions of site data acquisition, the procedures used for quantifying earthwork and estimating equipment productivity, and correlations of these with a required task sequence to generate a construction schedule.

The evolution of the modern large diameter rolling contact bearing is traced from early engineering concepts to today's modern bearings which are able to perform in multiple load situations. The benefits of the slewing bearing design concept are explored and applied to large lifting capacity applications. Several alternative slewing bearing options are discussed and compared.

The double drawbar dolly eliminates articulation of the conventional single drawbar converter dolly to improve the stability of multiple trailer truck combinations. It is usually provided with a self-steering axle to improve maneuverability. This paper describes double drawbar dolly types, factors in their design, and findings from tests of a specific dolly and computer simulation results pertaining to a range of dolly concepts. Performance topics investigated include low and high speed offtracking, stability characteristics and loads at the dolly hitch. The results showed vehicle performance is highly dependent upon friction and stiffness in the dolly self-steering system. Both test and simulation showed that compared with the single drawbar dolly, a double drawbar dolly having properties equivalent to that tested would significantly improve vehicle stability.

As a direct result of the Mining Industries need to improve efficiency and production in Open Pit type operations, the size of haulage units have increased dramatically. This trend has continued such, that the majority of dump trucks operating in Open Pit operations are in the 170 ton class. Continued mining in existing locations has meant that the increase in vertical lift and resultant grades, and increases in hauling distances are making electric drive systems unsuitable. This is largely due to the electric drive systems heat limitations on major propulsion components. With these mining requirements in view and the present limitations on electric drive systems in mind, Komatsu have been developing the Komatsu HD1600M. A diesel powered mechanical drive dump truck capable of operating in deep pit operations. This presentation introduces: Komatsu HD1600M Dump Truck

This paper highlights the installation requirements for textured spray control flaps fitted to heavy duty trucks. Tractor-trailer combinations operating on wet roads at highway speeds generate visibility impairing spray clouds. A key source of this fine droplet spray formation occurs when high velocity water thrown from truck tires impacts hard surfaces such as fuel tanks or conventional smooth surface flaps. Textured flaps absorb the tread throw impact returning the water to the road surface in large droplets. This paper addresses the placement of the flaps for optimizing spray control efficiency. Special focus is placed on the practical flap fitment behind the tractor steered and drive axles and the rear trailer axle. Moreover, the need for stronger flap support systems is addressed to accommodate the greater snow accumulations characteristic with textured spray control truck flaps.