The invention discloses a constant
tension control device of a hydraulic
winch, which is particularly applied to constant
tension control. An electro-
hydraulic control system comprises an
oil tank, a power pump group, an electromagnetic
reversing valve, hydraulic locks, pressure sensors, a motor
safety valve, a
hydraulic motor, a
winch, a cable arranger, a tension sensor, a load, a
programmable logic controller (PLC), a one-way throttling valve, an electric-hydraulic proportional overflow valve and a cooling valve, wherein the power pump group is connected with an oil inlet of the electromagnetic
reversing valve; oil outlets a and b of the electromagnetic
reversing valve are connected with the hydraulic locks and the one-way throttling valve, respectively; an oil return inlet of the electromagnetic reversing valve is connected with an oil inlet of the electric-hydraulic proportional overflow valve; an oil outlet of the electric-hydraulic proportional overflow valve is connected with the cooling valve; an oil return inlet of the cooling valve is connected with the
oil tank; the two symmetric hydraulic locks on oil paths corresponding to the two oil outlets of the electromagnetic reversing valve are connected with openings A and B of the
hydraulic motor, respectively; the motor
safety valve is arranged in parallel between two oil cavity openings A and B of the
hydraulic motor. The constant
tension control device of the hydraulic
winch has functions for setting and measuring the tension state of a cable and making the tension state constant under complicated sea conditions, and is high in response speed and high in anti-interference performance.