Single Axle Dump Truck

Dump Trucks, the Beginning

The dump truck as we know it today, had its beginnings at the turn of the century.  The first dump bodies were developed in England and Scotland, generally out of the need to transport and unload coal more easily.  The “Robertson Steam Wagon“, which was built in England in around 1905, is generally credited with being the first "hydraulic" hoisted dump truck. The power to raise the dump body came from either its engine or a separate steam engine.

Another early version of the dump truck was developed by a Scottish firm, the Alley & MacLellan Company, that used a "tipping cylinder" which ran along side the body of the truck.  Water was pumped into the cylinder, either backwards or forwards to operate the dump body up or down.  These new developments replaced the simple gravity operated dump bodies.
The "gravity dump" truck bodies pivoted off center, when the body was level it was secured in place, when the securing mechanism was released the body would tilt by gravity, and dump the contents.  When the contents were dumped, the body would then settle back into the level position, where it would once again be secured in place.

The forerunner of the modern coal hopper or bottom dump trucks featured a dump body that was split into two sections on the bottom.  These two sections were hinged and held in place by a ratchet driven chain .  When the operator wanted to dump the contents, he  would press down on a pedal which would release the ratchet holding the chain.  The two halves would split apart, and dump the contents out the bottom of the truck.  When the dump body was empty of its weight, it would settle back down into place.

Innovations, new technologies, and increased horsepower, allowed the dump truck to increase in size and hauling capacity to evolve into today’s behemoths like the Komatsu 930E-2, which measures 21 feet high, 46 feet long, has a capacity of 319 tons, and is powered by a 2,550 horsepower motor.  Now that’s a dump truck!