US Patent 10322587 Liquid discharge apparatus and cartridge

A liquid discharge apparatus includes a case receiving a cartridge having a first chamber, a tank having a second chamber, a head, and a controller to: calculate outflow amount Qa flowed from the second chamber for a time period Δt based on discharge amount Dh; calculate outflow amount Qc flowed from the first chamber toward the second chamber for the time period Δt based on the outflow amount Qa and flow path resistances; read liquid amounts Vc and Vs of the first and second chambers from a memory; subtract the outflow amount Qc from the read liquid amount Vc to calculate new liquid amount Vc; subtract the outflow amount Qa from the read liquid amount Vs and add the outflow amount Qc to calculate new liquid amount Vs; and store the calculated liquid amounts Vc and Vs in the memory.