Pressure-regulating chamber comprising float valve biased towards closure by inlet ink pressure

摘要

A pressure-regulating chamber for maintaining ink contained in the chamber at a predetermined first level relative to a printhead. The chamber comprises: an inlet port for connection to an ink reservoir via an ink supply line; an outlet port for connection to an ink inlet of a printhead via an upstream ink line; an air vent open to atmosphere; and a float valve for maintaining the predetermined first level of ink by controlling a flow of ink into the inlet port. The float valve is biased towards a closed position by a positive ink pressure at the inlet port.