| 摘要 |
PROBLEM TO BE SOLVED: To provide a crane hydraulic circuit which can perform a composite operation of a main hoist or an auxiliary hoist winch and an undulation winch without pressure interference.SOLUTION: A hydraulic circuit is equipped with an auxiliary hoist winch which is driven by a pressure oil which is supplied from a first hydraulic pump via a first auxiliary hoist control valve and/or a pressure oil which is supplied from a second hydraulic pump via a second auxiliary hoist control valve. An undulation control valve and the first auxiliary hoist control valve are connected to the first hydraulic pump in series, and a main hoist control valve and the second auxiliary hoist control valve are connected to the second hydraulic pump in series. The hydraulic circuit is equipped with a selection unit which selects either a first state in which the auxiliary hoist winch is driven by only the pressure oil supplied from the first hydraulic pump via the first auxiliary hoist control valve, or a second state in which the auxiliary hoist winch is driven by only the pressure oil supplied from the second hydraulic pump via the second auxiliary hoist control valve.SELECTED DRAWING: Figure 3 |
