AFgatEST PRODUCTS LABORATORY h LIOREST SERVICE
U. S. 1D E PARTMENT OF AGRICULTURE
(13-0)
IMPROVED HARVESTING METHODSL,
EQUIPMENT SURVEY NOTES
AUTOMATIC TRIP STAKES
Log-truck stakes that are automatically tripped to dump the load
without the driver having to leave the truck cab have been developed by a
Lake States logger. He has fitted a standard
6 by 6 truck with a steel
side-dumping bed with 8-foot bunks made of 8-inch I-beams. A 2-inch by
2-foot hydraulic piston run by the truck's power take-off raises one side
of the bed 2 feet (fig. 1). This is sufficient to trip the stakes and
roll the load off the truck. Figure 2 illustrates how the stake-tripping
device works.
"A" is a stationary bunk, and "B" is the moving bunk. As the far
side of bunk "B" is raised by the piston, the near end moves downward.
The lug "C" engages the bottom of the stake and raises it, causing the
retaining lug "D" to be disengaged from its stocket "E".
This truck is being used around the mill yard exclusively, but
there is no technical reason why it could not be used for hauling. It is
also mechanically possible to adapt this same principle to a truck with a
logging trailer by using two hydraulic cylinders instead of one.
E. W. Fobes
May 1951
Information furnished by Leland W. Hooker, Timber Technologist,
Michigan College of Mining and Technology, Houghton, Mich., and
Upper Michigan and Wisconsin, Timber Producers' Association,
Ironwood, Mich. April 1951.
Rept.No. R1637-45
Agriculture-Mad'
\)le,
Maintained at Madison, Wisconsin in cooperation with the University of Wisconsin Z M 87195
OCT
A A)
9 1951
F
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Figure 1.--General view of logging truck and body raised.
Figure 2,--Details of trip stake.
Z 14 87196 11'