US Patent 7866345 Non-clogging flow restriction for pressure based flow control devices

A flow metering device includes at least two stackable modular bodies including at least one set of adjacent modular bodies, each modular body having an orifice for modulating fluid flow therethrough. The modular bodies arranged such that the orifices between adjacent modular bodies are offset from each other. Adjacent stacked modular bodies define a chamber for trapping particulates entrained in fluid flow without obstructing fluid flow through the orifices.