| 摘要 |
PROBLEM TO BE SOLVED: To provide a hydraulic circuit having a circuit configuration capable of improving operability of an optional attachment fixed to a loader more than that of the prior art attachment.SOLUTION: An optional direction changing-over valve 6 in a hydraulic circuit 1 is arranged in an unload passage 21 at a more upstream side than a direction changing-over valve 7 for an arm and a direction changing-over valve 8 for a bucket. In addition, this circuit is constituted in such a way that to the optional direction changing-over valve 6 is supplied hydraulic oil from a hydraulic oil supplying passage 22 branched from the unload passage 21 at a more upstream side than the optional direction changing-over valve 6; to the direction changing-over valve 7 for an arm is supplied hydraulic oil from a hydraulic oil supply passage 23 branched from the unload passage 21 between the optional direction changing-over valve 6 and the direction changing-over valve 7 for an arm; and to the direction changing-over valve 8 for a bucket is supplied hydraulic oil from a hydraulic oil supply passage 24 branched from the unload passage 21 between the optional direction changing-over valve 6 and the direction changing-over valve 8 for a bucket. |
