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THEORY OF OPERATION
1. The Tulsa Planetary Winches are composed of an input from
either a high torque, low speed geroler motor or a high-
speed gear or piston motor. Input drives through a multiple
disc brake that is spring applied and hydraulically released,
and then through planet gear sets to the cable drum.
2. During inhaul, the brake is not released since the load is
driven through a one-way cam clutch, bypassing the brake.
When the load comes to a stop, the cam clutch locks up and
the load is prevented from moving by the brake.
3. During payout, a brake valve is used to prevent the load
from moving faster than desired. This brake valve partially
blocks the main line from the motor back to the directional
control valve, allowing only a limited amount of oil through
the motor. Also, any time there is sufficient pressure to
modulate the brake valve, this same pressure releases the
multiple disc brake.
USING A SNATCH BLOCK
By using a snatch block you have effectively cut the load on the
winch in half. A snatch block should be used any time you have
a concern about the ability of the winch or cable to move a load.
The following illustration shows one way to rig such a block.
