| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a priority valve that is hardly influenced by pressure fluctuation. <P>SOLUTION: In the priority valve, a sub spool 15 is incorporated in a main spool S. The sub spool is constructed to control an opening degree of a third control passage section 25 according to the movement position. One end of the sub spool is engaged in a first pilot chamber 16 and the other end thereof is engaged in a second pilot chamber 17. The sub spool is kept at a position where the action force of the first pilot chamber balances with that of the second pilot chamber. At the balancing position, the sub spool closes the third control passage section 25 or increases the opening degree of the third control passage section 25. Further, when the third control passage section is closed, a first control passage section 10 communicates with one pressure chamber 6 which keeps one end of the main spool engaged only via a damper orifice 22 formed in the sub spool. <P>COPYRIGHT: (C)2008,JPO&INPIT |
