Reservoir height extender for lash adjuster assembly

Claim 1

An improved fluid operated lash adjuster assembly for preventing back lash in of an internal combustion engine valve member drive train, said assembly including a body member mounted on the engine, said body member having a bore therein having an open end and a closed end surrounded by a wall thereof having a first fluid passageway therethrough communicating between the body member bore and a source of fluid, a plunger member moveably disposed within said body member bore and having a fluid resevoir therewithin whose capacity is defined by the height of a second fluid passageway through a side wall thereof surrounding said chamber for receiving fluid from the first passageway, said assembly having a fluid pressurization chamber between said resevoir and said body member closed end and including one-way valve means beetween said resevoir and said pressurization chamber operable to cyclically pressurize fluid from the resevoir in response to reciprocating movment of the plunger member in response to rotation of a rotary cam member driven by the engine, wherein the improvement is characterized by said plunger member including an inverted hollow insert member disposed within said plunger member chamber, said insert member having an open-end thereof facing toward the closed end of the body member bore surrounded by a periphery of the insert member that is secured in fluid tight sealing engagement with the wall of the plunger member surrounding the chamber below the location of said second fluid passageway, said insert member having a generally closed upper-end above said second fluid passageway having at least one fluid entrance opening therethrough providing fluid communication between said plunger member chamber and said resevoir, and said insert member having a side wall thereof displaced from the plunger member wall surrounding the chamber sufficiently to provide a third fluid communicating passageway between the second fluid passageway and said insert opening enabling fluid to flow from the second passageway through the insert opening and into the resevoir enabling the resevoir to rise within said insert member above the location of the second fluid passageway thereby enlargening capacity of the resevoir and enhancing operation of the assembly.