Patent ID: 7607750

Claim:
A pump control mechanism, comprising: a pump unit, comprising: a pump member, adapted to be cyclically moved to apply an air pressure to a liquid supply source to thereby supply liquid stored therein to a reservoir member; and a driving source, configured to be driven in accordance with control information to move the pump member; a position sensor, sensing a position of the pump member; a first storage, storing target information indicative of a target driving speed of the driving source; a first calculator, operable to obtain drive information indicative of an actual driving speed of the driving source based on the sensed position of the pump member; a second calculator, operable to obtain a difference between the target driving speed and the actual driving speed, and obtain first correction information for reducing the difference; and a corrector, operable to correct the control information with the first correction information, wherein: the driving source is driven by a voltage signal having a pulse waveform; and the control information includes a duty ratio of the voltage signal in connection with a pulse width modulation technique, and the first correction information includes data for varying the duty ratio.