Elliott Traffic Safety Service L60, Руководство оператора

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INTRODUCTION AND THEORY OF OPERATION
The 506W planetary winch design is composed of an input from a high torque, low speed geroler
motor or a high speed gear or piston motor, driving through a multiple disc brake, through a
planet set to the cable drum.
The multiple disc brake is spring applied and hydraulically released through a port in the brake
housing. 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.
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. The brake valve is modulated by sensing
pressure on the other main line, the line from the directional control valve to the motor. Also, any
time there is sufficient pressure to modulate the brake valve, this same pressure releases the
multiple disc brake.