| 摘要 |
<p>A shock absorber of the direct acting hydraulic type is disclosed as comprising a reciprocable piston having a piston body, the piston body being formed with first and second sets of spaced flow ports, the sets of flow ports being concentrically oriented with the first set being spaced radially inwardly from the second set; a first valve seat on one end of the piston body adjacent the first set of flow ports; a first valve member engageable with the first valve seat to block fluid flow through the first set of flow ports; second and third valve seats on the opposite end of the piston body and located radially inwardly and outwardly from the second set of flow ports; a second valve member in the form of a flat annular valve disc disposed adjacent the second and third valve seats and engageable therewith to block fluid flow through the second set of flow ports; an annular compression plate disposed on the axially opposite side of the valve disc from the piston body; the compression plate having axial movement relative to the piston body between a first position maintaining the second valve member adjacent the second and third valve seats but permitting a first magnitude of fluid flow through the second set of flow ports, and a second position wherein the second valve member is displaced predeterminately from the piston body to permit a second magnitude of fluid flow through the second set of flow ports, and at least one spring disc yieldably resisting axial movement of the plate and the valve disc.</p> |
