| 摘要 |
PROBLEM TO BE SOLVED: To provide a small-sized fluid control valve which can suppress pulsation generated at the minute opening of an input port 7, and can obtain desired flow rate performance at a full-open stroke.SOLUTION: At one end side of a first land 11 in an axial direction, there is arranged a stepped throttle part 16 which has a step r1 in an inside-diameter direction rather than an edge part e, and has a curved face shape (protrusive R part) which becomes protrusive in the axial direction and a radial direction with an anti-edge part side of the step r1 as a starting point s1. At a minute opening for starting to open a flow-in port 7a, the port is throttled by the passage of a working fluid through a second gate which is opened between a corner part of a sleeve 4 and the protrusive R part, and thereby an abrupt increase of a flow rate and the instability of control can be suppressed. Furthermore, since an opening area of the second gate becomes large at a full-open stroke, the performance of a maximum flow rate is not impaired. Also, since an injection flow is changed to an inward flow in the radial direction along the protrusive R part at the full-open stroke after the minute opening, a fluid force generated in the axial direction becomes small. |
