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Viewing 163861 to 163890 of 188274
1972-02-01
Technical Paper
720786
Joseph Fox, Luft A. Alvi
This paper describes a hoist dynamometer capable of reproducing field conditions for the purpose of providing comparative data on friction materials used on band brakes and clutches by the crane and hoist industry. Performance qualities essential to the braking system are recorded for both automatic and manual operation. The dynamometer enables the testing to be performed under controlled conditions which can be both repetitive and reproducible.
1972-02-01
Technical Paper
720784
C. A. Brolin, H. E. Durscher, G. Serentha
A series of tests to ultimate failure was conducted on lattice type crane booms. The results of these tests, correlated to predicted mathematical values, demonstrated that ultimate load capacity can be predicted accurately and that SAE J987 “Crane Structures-Method of Test” results in proper but probably conservative ratings. The proposed SAE Recommended Practice, “Latticed Crane Booms-Analytical Determination of Stresses and Critical Loads,” appears to give reasonable ratings when compared to actual failure loads. This work and results presented suggest that the day may come when such structures can be rated based on ultimate or critical load rather than on critical stress.
1972-02-01
Technical Paper
720778
Leonard Reimer
A compensated hydraulic system is a system in which the pump automatically compensates or reacts, usually by a change in displacement, to some change in its operating condition or to some external signal. An almost endless variety of operating characteristics to provide many conveniences is possible. Pressure- and flow-compensated systems are familiar but still have new possibilities. In addition, torque compensation, speed compensation, and various hybrid systems are now feasible. The features of several existing and proposed systems are examined in this paper.
1972-02-01
Technical Paper
720780
John M. Karhnak
Over the past several years, the Army has become increasingly aware of the disastrous effect of solid particle contamination on the life and efficiency of fluid power system components. Something must be done to give a more reliable, quicker, and more accurate check on the system condition at any given time. In July 1971, the Army Mobility Equipment Command acquired a prototype portable automatic particle counter for use on fluid power systems. This battery-operated counter connects directly to the vehicle or test stand at a fixed, predetermined test point, eliminating the need for sample containers and simplifying the test procedures. Connection, analysis, and disconnection takes less than 5 min. The portable counter has been used on a number of vehicles with verification samples being taken and checked by Oklahoma State University. Results to date have encouraged the Mobility Equipment Command to continue with the field verification program.
1972-02-01
Technical Paper
720779
Kurt R. Lonnemo
This paper describes the design, steady-state and typical dynamic performance characteristics of a line of pressure and flow compensated pumps. Particularly, the influence of the application parameters on the dynamic characteristics is discussed and illustrated. Some installation considerations are also given and a few successful applications (to farm tractors, dozers, trucks, and jumbojets) are demonstrated.
1972-02-01
Technical Paper
720774
Rodney H. Anderson, George R. Heidenblut
The 528 wheel skidder represents a second-generation machine designed and tested to satisfy the requirements of the large wood areas of the world. Numerous unique features were incorporated in the design to meet the special needs of the logging customer; these are described, along with the development program that yielded the present vehicle.
1972-02-01
Technical Paper
720773
L. E. Miller
The forestry products manufacturers are being forced by economic pressures into producing wood handling equipment of larger capacity and more efficient operation. Consequently, four-wheel drive articulated skidders of larger sizes and increased horsepower are being designed and built. John Deere's JD740 Skidder is one of these units. This paper presents the design features of the JD740 and discusses aspects of these features important in their selection to meet the original design goals.
1972-02-01
Technical Paper
720776
N. Hay, P. L. Jones
A survey of spray literature has been carried out in order to find all those works containing a theoretical or experimental correlation of spray penetration variables. Twelve such works were found. Three hypothetical sets of conditions based on actual data from the Sulzer LVA24 diesel engine are used to test the correlations. The results obtained from applying the three sets of conditions are given as penetration-time curves. The effects of injection pressure, air density, and nozzle orifice diameter on the penetration predicted by each correlation, are also shown in penetration-time curves. An analysis of the results leads to several conclusions from which recommendations are made as to whether each correlation is suitable for use under conditions prevailing in modern diesel engines. Future trends in medium speed diesel engine conditions show that all but two of the twelve correlations will not give satisfactory predictions of penetration under these conditions.
1972-02-01
Technical Paper
720769
W. L. Sumpter
Many of the requirements for rotary power on farm, construction, and industrial machinery can be best satisfied by the use of hydraulic motors. Remote mounting capability, unlimited rotation, reversibility, good variable speed control, and small size and weight are some of the general advantages made possible by the use of hydraulic motors. More specifically, low-speed high-torque hydraulic motors offer even more advantages to the product designer. In many cases these motors eliminate the need for gearboxes and reduce the number of other mechanical components, thereby providing increased design flexibility in the end product.
1972-02-01
Technical Paper
720771
George D. Herbst
The Hyster C610A represents a unique concept in self-propelled vibratory compactors. A single trunnion mounted high flotation drive-steer tire was the basis for achieving major design objectives of improved traction and maneuverability. Hydrostatics has been employed throughout for transmission of engine power. Required for the new design concept was a rotary hydraulic union with capacity for 50 gpm and 4700 psi. Problems related to the hydrostatic transmission, drive tire, and controls were solved, resulting in a durable and efficient compaction tool.
1972-02-01
Technical Paper
720772
Ronald G. Rumpf
Twin-powered self-loading scrapers are relatively new in the construction equipment field. The high horsepower to weight ratios coupled with all-wheel drive give two axle scrapers excellent performance in the cut, on the haul road, and in the fill area. Self-loading is accomplished with heavy-duty elevator systems. Loading time and distance is less than that experienced with single engine elevating scrapers. This type of equipment, in the 20 and 30 yd3 class, is geared to handle a wide variety of construction and mining production jobs and has long since graduated from the “cleanup tool” and “potato dirt” type equipment.
1972-02-01
Technical Paper
720766
M. W. King
A rubber track has been developed for use on all-terrain vehicles (ATV). This track offers the advantages of low ground pressure, excellent climbing ability, long flex life, and puncture resistance. This track uses a series of internal lugs for propulsion and can be manufactured with any desirable tread pattern. This paper will present the advantages and some of the technical aspects of this track.
1972-02-01
Technical Paper
720765
M. L Pules, D. J. Eves
Flotation tires on all-terrain vehicles (ATV) are an essential component for good, overall off-the-road mobility. Water displacement by the large volume tires provide additional buoyancy for amphibious vehicles. The large contact area of the deflected tire provides low ground pressure for flotation on soft ground. ATV tires are a special breed of tires with design features for better mobility such as carcass flexibility, wide tire section, and special tread design.
1972-02-01
Technical Paper
720768
Richard A. Klimaszewski
Speed and pressure response of a hydraulic motor to changes in flow (stroking a directional valve) is predicted for typical mobile hydraulic circuits. A simplified approach was used to derive the equations for a system consisting of a pump, directional valve, and a motor with an inertia load. The speed and pressure response to increases in flow was studied by solving the equations on an analog computer. Expressions for the natural frequency, ωn, and the damping ratio, ζ, were written in terms of motor displacement, load inertia, system compliance, and system leakage coefficient. The response to increases in flow is presented in terms of the damping ratio. The response to decreases in flow is discussed for directional valves with both open and closed cylinder ports. The effects of the simplifying assumptions of the valve stroking rate and of the valve cylinder port configuration are discussed.
1972-02-01
Technical Paper
720759
Bernard B. Poore, Gordon Wright, Bernard E. Romig
A new power systems evaluation technique was developed to compare average fuel consumption and output power capability between different systems. Many combinations of engines, transmissions, and control systems could be represented by a modular general-purpose power train simulator. The torque and speed requirements of a vehicle were represented with a stochastic model. This technique was applied to the selection of a gas turbine transmission system for an off-road vehicle.
1972-02-01
Technical Paper
720761
George Edema
The solid waste disposal industry in the United States is confronted with a tremendous challenge. While being transformed, almost overnight, into a sophisticated organization of collectors and disposers, having to adhere to new and complex environmental laws, we are handling even greater demands for service. New laws and regulations are being enacted so rapidly that many of our present methods of operating, and our present equipment, are being made obsolete before we can develop suitable replacements. The energy and talents of the automotive and supporting industries are urgently needed to design and produce new types of collection equipment that will be economical, safe, and capable of meeting this ever growing challenge.
1972-02-01
Technical Paper
720762
Eugene J. Wingerter
Within the past 15 years, the solid wastes management field has experienced an extensive technological advancement. This advancement has brought the field into parity with other segments of the materials handling and construction industries. During the coming decade the solid wastes industry will experience a continual technological refinement and maturity in areas of waste collection, transfer systems, resource recovery, and disposal. The rapidly expanding demands for service combined with the constraints for economical systems for waste management will accelerate the automation of selected processes formerly based upon labor-intensive procedures. This paper highlights the current state-of-the-art for waste management and identifies areas where technological improvements could lead to significant manpower and productivity achievements in the field.
1972-02-01
Technical Paper
720751
James Giovanetto, Carl Kacynski
The noise levels of earthmoving equipment, in the operator's cab and outside the machine, are discussed. Ways and means of lowering the dB ratings for increased operator and by-stander comfort are taken into account. Suggestions are made for ways of mounting the cab itself and lessening vibratory reactions from the engine, including rubber engine and cab mounts, plus acoustical material for reducing inside the cab noise.
1972-02-01
Technical Paper
720752
Donald R. Hartdegen, Herbert G. Akins
Developing procedures for evaluating and reducing operator's noise levels is a common challenge for all machine manufacturers. Although individual approaches will vary with each individual, industry, or equipment type, the end result is a method to evaluate and develop the control of noise. One such approach used on large farm tractors with cabs is described in this paper. It describes the application of general sound control theory and some of the benefits obtained. Each modification made on the product has its own unique procedure for analysis. This paper does not assume these procedures will solve other noise problems, but they can be used as a guide.
1972-02-01
Technical Paper
720754
James M. Butler, Donald R. Buerschinger
The WABCO model 3200 3 axle, 200 ton mining truck was announced in the fall of 1971. It employs a 2000 HP electro-mechanical drive system to power tandem rear axles. The power train consists of an EMD 12-645-E4 900 RPM locomotive type engine, generator, controls and two (2) drive motors. Each tandem axle has one (1) motor, which drives the wheels through a reduction gear set, a differential and planetaries. This paper describes the features of the drive system and its unique contributions to vehicle design and performance.
1972-02-01
Technical Paper
720743
Masatoshi Satake, Tsuneo Mukai
The problems due to the soft soil often found at job sites in Japan call for a tire superior in traction and flotation to be used on wheel-type earthmovers. We have developed several types of experimental tires by applying various theories about such influences on the characteristics of tires as configuration of the tire, internal structure, and design of the tread. Tests on such experimental tires have been conducted with a new machine for evaluating the traction and flotation of earthmover tires. After careful experimentation and testing, we formulated a theory, which is a slight modification of Bekker's experimental formula, and this theory has been proved to be applicable to common practices in the field.
1972-02-01
Technical Paper
720744
Eugene Ring, Gil Kiefer
A relatively new technique for combining fiberglass reinforcements and polyester resins into reinforced plastic parts has given reinforced thermosets the capability of approximating metal finishes. This material is sheet molding compound, commonly called SMC. It has been used successfully in large quantities by automotive companies for the past four years. This paper covers the successful application of SMC from basic design to use in the field of some recreational and farm implement components. Several proven advantages are listed for the use of fiberglass-reinforced plastic and SMC in particular.
1972-02-01
Technical Paper
720745
Dan A. Nordstrom
An engineering development team approached a snowmobile track manufacturing project with an objective of creating a unique salable product. Keying off a new internal lug drive system, this report describes the analysis used in selecting polyurethane as the elastomer, the development of a suitable manufacturing method and some of the facets of tread design.
1972-02-01
Technical Paper
720747
Tetsuzo Fujikawa
This paper describes aspects of the Kawasaki two-stroke engines for snowmobiles. Generally speaking, in order to obtain good results in developing engines for snowmobiles, it is important not only to investigate the engines themselves, but also to match their performance with those of the snowmobile, including their power-transmitting system. Kawasaki has developed an ignition system for firing two plugs per cylinder, which prevents abnormal combustion and results in higher performance.
1972-02-01
Technical Paper
720914
John Carter
A review of the long-standing highway truck ride problem and conventional solutions emphasizes an increased usage of suspension seats to isolate the driver from predominant cab vibration. A novel new suspension seat (Hydra-Flex) features an articulated linkage which conforms to similar kinematics as natural motion of the human body. Further, this linkage inherently provides an action which cancels the characteristic back-slapping motion of truck cabs. Numerous inherent advantages over conventional designs of suspension seats are disclosed, and these features are attributed to the “bionics” principle which is involved.
1972-02-01
Technical Paper
720913
D. E. Runkle, U. Grinbergs
Improved power brake booster designs and systems with redundant capabilities are anticipated to be required as a result of the new safety regulations for improved stopping distances, and indirectly, as the result of the new emission controls because of the potential loss of vacuum availability and increased underhood temperatures. In early 1968 it was becoming obvious to certain brake engineering groups that a new brake booster system with reserve capabilities for truck hydraulic brakes would be a requirement in the near future. Bendix, as a major independent supplier of power brake boosters, had more than a casual interest in this trend appearing over the horizon. As the result of discussions with customers and our internal analysis of various power booster systems, hydraulics, in the form of the Bendix Hydro-Boost system with an integral electric motor pump backup, was settled upon as one major approach to best serve the industry.
1972-02-01
Technical Paper
720912
Bruce C. Brenner
Increasing underhood temperatures and decreasing availability of vacuum, indirectly caused by more stringent safety and emission control regulations, brings the possibility of central hydraulic systems closer. However, as the central system fully evolves, equipment manufacturers indicate that they expect a transition step, where the same fluid will be used in both the power steering and power braking systems. With the expected demands on fluids to be used in such systems increasing, Dow Corning has initiated the development of a silicone candidate, based on the most readily available silicone fluid, dimethylpolysiloxane. The recent advances in lubrication technology, information on compatibility with presently used materials, and the inherent physical and chemical properties which allow a silicone fluid to be a serious candidate for such usage, are presented.
1972-02-01
Technical Paper
720916
David L. Paul
The use of a computer-generated vehicle mission simulator has made it possible for truck operators and manufacturers to select a horsepower-to-weight ratio to fulfill the requirements for operation over a known terrain. This practical presentation shows several specific applications of the procedure and offers some conclusions drawn from those applications.
1972-02-01
Technical Paper
720915
Arthur Harder
A new and different seat suspension suitable and advantageous for off-the-road and highway vehicles is presented. Contributing to a comfortable ride for the operator are several proved features, to which have been added three new and unique features. The seat suspension is an air-oil cushioning system to which has been added a servo-linkage to operate a two port hydraulic valve; the servo-linkage being tied to the vertical seat motion. The new, unique features are: 1. Unlimited range of adjustment of seat vertical position to suit the individual operator, assuring him of easy access to the brake pedal, good vision, and comfort, regardles of his particular body dimensions. 2. At any vertical seat position the operator chooses, automatic adjustment for the weight of the operator. 3. Clearance between the front edge of the cushion and the rim of the steering wheel, once set to the operator's liking, is maintained, including the time while the operator is dismounting and remounting.
1972-02-01
Technical Paper
720904
A. A. Choma
The operation and application of the NoSPIN and Tandem-Lock differentials to power transmissions is described. The three types of NoSPIN-standard, silent, and silent-overrunning-and two of Tandem-Lock-conventional NoSPIN and inside-out design-are described, and the positive and negative features of each are considered. The paper points out the early design deficiencies and the corrective action taken to overcome them. The application guidelines of the NoSPIN and Tandem-Lock differentials are also covered so that proper application of the differentials can be carried out.

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