Patent ID: 7887170

Claim:
A pressure-regulating chamber for maintaining ink contained therein at a predetermined first level relative to a printhead, said chamber comprising: 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, said air vent communicating with a headspace above said ink; and a float valve for maintaining said predetermined first level of ink by controlling a flow of ink into said inlet port, wherein said float valve is biased towards a closed position by a positive ink pressure at said inlet port, wherein said float valve comprises: an arm pivotally mounted about a pivot; a float mounted at one end of said arm; and a valve stem attached to said arm, said valve stem having a valve head for closure of a valve seat, said valve seat being positioned at the inlet port of said pressure-regulating chamber.