| 主权项 |
1. A method of manufacturing an eccentric valve, comprising:
providing a valve body having a through hole disposed at center in an axial direction, and a first shaft hole disposed in a longitudinal direction to pass through the through hole, a centerline of the first shaft hole deviating from a center of the through hole, the axial direction being perpendicular to the longitudinal direction; providing a ring-shaped valve seat having an inner edge surface thereof consisting a part of a tapered face of an oblique cone, the valve seat having a thickness in the axial direction; accommodating the valve seat in the through hole and disposing the valve seat in the valve body, enabling a peak of the oblique cone to offset from a first axial centerline passing through the center of the through hole, and enabling the accommodated position of the valve seat to deviate from the position of the first shaft hole; providing a disc-shaped valve unit having an annular surface and a pair of second shaft holes provided in the longitudinal direction of the valve unit; providing a seal which is a centrosymmetric ring, an outer edge surface thereof being a cambered surface with a fixed curvature; disposing the seal on the annular surface of the valve unit, enabling the disposal position of the seal on the annular surface to deviate from the disposal position of the pair of second shaft holes; accommodating the valve unit in the through hole and aligning the pair of second shaft holes with the first shaft hole, enabling the outer edge surface of the seal to face against the inner edge surface of the valve seat; and providing a bar-like valve stem configured to penetrate the first shaft hole, pass through the through hole and penetrate the pair of second shaft holes, so as to control the rotation of the valve unit in the through hole; wherein the curvature of the outer edge surface of the seal on any radial cross-section is determined through the following steps: taking a radial cross-section passing through center of the valve seat such that the radial cross-section intersects the inner edge surface within the range of thickness of the valve seat to form a first line segment and a second line segment, the first line segment and the second line segment being respectively located on two opposite sides of the first axial centerline with a 180-degree difference, and absolute values of slopes for the first line segment and the second line segment being mutually different; using the first axial centerline as a mirror line to create a mirror line segment from the second line segment, the mirror line segment and the first line segment being located on the same side of the first axial centerline, the mirror line segment and the second line segment being symmetric about the first axial centerline; and determining an arc being tangent to the first line segment and the mirror line segment, and taking a radius of curvature of the arc as a radius of curvature for the outer edge surface of the seal on any radial cross-section. |
