| 摘要 |
PROBLEM TO BE SOLVED: To provide a hydraulic control device with the number of part items reduced, reduced cost of the whole of a device and capable of restricting the energy loss. SOLUTION: A lowering speed control mechanism 30 assembled in a body 34 is provided with an assembling hole 39 provided on the way of a connecting flow passage 32 formed in the body, a spool 40 assembled in the assembling hole freely to slide, a first pilot chamber 11a facing to one end of the spool, a second pilot chamber 11b facing to the other end of the spool and assembled with a spring 11c, a communication hole 52 formed in the spool and communicated with a cylinder side at one end thereof and communicated with the first pilot chamber at the other end thereof, a check valve 25 assembled in the communication hole to allow the only oil flow from a cylinder side to the first pilot chamber, a damper orifice 24 provided in the periphery of the spool to always communicate the first pilot chamber with the cylinder side, and throttle flow passages 22, 49 and 50 formed in the spool to communicate the cylinder side with a selector valve side.
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