US Patent 11598429 Eclipse valve assembly

An eclipse valve includes at least two reciprocating obturator plates captured in a sealed housing. The obturator plates fill the width of a cavity within the housing and can be moved between aligned and unaligned positions. Each of the obturator plates have an opening through the plate, and when the obturator plates are aligned, the openings through the plates are aligned with each other, and with front and rear openings in the housing, allowing flow through the valve. The plates can be moved to reduce the overlap of the openings through the plates within the housing in an eclipse manner to adjust the rate or amount of flow, and to shut off flow by completely un-aligning the openings.