Patent ID: 9732863
Date: 2017-08-15
CPC Classifications: F15B,F16K,Y10T

Claim:
1. A fluid control valve comprising: a sleeve defining a spool hole; and a spool inserted into the spool hole and being slidable relative to the sleeve in an axial direction of the sleeve, wherein the sleeve includes an inlet port and an outlet port which are communicating with the spool hole, the spool includes a first land, a second land, and a shaft portion, the first land and the second land are slidable relative to an inner peripheral surface of the sleeve, the shaft portion is connected with both the first land and the second land in the axial direction, the inlet port has an inlet opening opened at the inner peripheral surface of the sleeve, the inlet opening having a width that corresponds to a fully open stroke, when the first land opens the inlet opening according to a movement of the spool, the inlet port communicates with the outlet port, an outer-peripheral corner of the first land opening and closing the inlet opening is an edge portion, the first land opposite to the second land via the shaft portion in the axial direction includes, a throttle portion having an approximately vertical surface distant, from the edge portion by a first predetermined distance in the axial direction, a start point is at a position of the first land distant from the edge portion by a second predetermined distance inward in a radial direction of the first land, the throttle portion has a curved surface that protrudes from the start point in both the axial direction and the radial direction and is smoothly connected with the approximately vertical surface, and the second predetermined distance is greater than or equal to 0.1 mm and is less than or equal to 60% of the fully open stroke, wherein the throttle portion has a start point that is set on the surface of the throttle portion inward of the start point of the curved surface, and the throttle portion includes a recess portion inwardly recessing from the start point of the throttle portion in the axial direction.