Variable area low speed orifice in a vehicle damper

Abstract

A vehicle damper includes a valve having of an imperforate, deflectable variable orifice disk with an outer periphery that is only partially clamped against a valve seat, during low velocity operation of the damper, by a variable orifice support disk having an outer periphery that is not coextensive with the outer periphery of the variable orifice disk. The portion of the outer periphery of the variable orifice disk that is not clamped against the valve seat deflects away from the valve seat during low velocity operation of the damper, in response to force on the variable orifice plate generated by pressure of fluid in flow apertures closed off by the variable orifice plate, to provide a variable orifice for fluid flow through the valve and digressive performance of the damper. The valve may take the form of a compression or rebound valve on the piston of the vehicle damper, or a base valve in a dual tube damper. The valve may take the form of a blow-off valve, a deflecting disk valve, a combination blow-off deflecting disk valve, or as part of other types of valves suited for use in vehicle dampers. A vehicle damper may include one or more variable orifice area low velocity valves in combination with other valves of conventional construction.