Effect of Weight/Power Ratio on Highway Transportation 520248

THE purpose of this presentation is to focus attention upon the need for improving commercial highway vehicles in order to keep pace with the new standards of comfort and operation now prevailing in passenger-car design. The tendency to reduce the number of motions and the physical effort required to perform a task has led to the use of automatic transmissions in automobiles.
Passenger-car manufacturers have designed higher-output engines without materially increasing weight, thereby providing a horsepower reserve which eliminates uneconomical operation of the engine at peak output at all times. Streetcars have been improved so that the operator need only apply foot-treadle pressure to start, accelerate, and stop the vehicle.
This appears to be in direct contrast to the trend in bus and truck design. An increasing number of motions on the part of the driver are required to get the commercial vehicle in motion, and to maneuver it in accordance with traffic, terrain, and safety dictates.
Many trucks and buses are powered with inadequate engines in combination with multi-speed transmissions and 2-speed axles for gear-splitting, in an effort to overcome engine deficiencies. The increasing traffic load on streets and highways, and the influx of new, inexperienced drivers in the trucking industry, has caused this situation to become more acute.
The writer suggests substituting certain engine, transmission, and axle combinations now in use, for similar available equipment selected so as to secure “matched ability” combinations.


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