Winch (2) is provided with means for preventing an overload comprising a relief valve (23), which in response to an overturning load in excess of a permissible value connects a hydraulic accumulator (16) to a hydraulic cylinder (4) for lifting the brake (3) of the hoisting mechanism and to the suction side (8) of the hydraulic motor (1) of the hoisting mechanism for a compensation of oil leakage so that the hoisting rope can be unwound from the hoisting drum (2). Characterisingly a second hydraulic motor (30) is provided, which is coupled to a hydraulic pump (31). Valves (24, 29) are provided, which are actuated by the hydraulic accumulator (16) and adapted to connect said hydraulic motor (30) to the pressure side of the hydraulic motor (1) of the hoisting mechanism, which latter hydraulic motor (1) operates as a pump during safety operation to feed motor 30 to cause pump 31 to feed oil to the circuit of the safety system even when accumulator 16 is empty. Said valves (24, 29) are also adapted to connect said hydraulic pump (31) to the hydraulic cylinder (4) for lifting the brake (3) and to the suction side (8) of the hydraulic motor (1) of the hoisting mechanism. IMAGE
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