To control flow rate correctly by a simple constitution in a hydraulic control device capable of controlling pressure.
Tapered control parts are formed at both ends of a spool 10 of a three-way control valve 2. The tapered control parts are constituted such that they have sliding regions for making a P port 5 and a T port 4 always communicate with a C port 3 and that the communicating opening area between the P port 5 and the C port 3 which is reduced by the spool 10 and the communicating opening area between the C port 3 and the P port 5 are reversely determined in response to the sliding position of the spool 10. A correct flow control is performed by identifying the flow of the C port 3 in consideration of the bleeding flow rate from the C port 3 to the T port 4.
SHINOHARA HIDEAKI
MAEHATA KAZUHIDE
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