Patent ID: 7637584
Filing Date: 2009-12-29
Classification: B41J

Abstract:
1. An image forming apparatus, comprising: a liquid ejection head including a plurality of nozzles arranged in a prescribed pattern in a first direction and a plurality of pressure generating elements provided to correspond with the plurality of nozzles respectively, wherein liquid is ejected toward a recording medium from the nozzles by supplying drive signals to the pressure generating elements; a plurality of drive waveform generating circuits which generate drive signal waveforms for driving the pressure generating elements; a circuit selection device which selectively switches the drive waveform generating circuits for applying the drive signal waveforms to the pressure generating elements, of the plurality of drive waveform generating circuits; a power source which supplies power to the pressure generating elements via the drive waveform generating circuits; a control device which selects a first drive waveform generating circuit used for driving each of the pressure generating elements, with respect to each of the pressure generating elements, of the plurality of drive waveform generating circuits, in such a manner that the liquid ejected from the nozzles is deposited substantially linearly in the first direction on the recording medium, and controls the circuit selection device in such a manner that the first drive waveform generating circuit is connected to each of the pressure generating elements; and a monitoring device which monitors whether an amount of momentary current consumption in each of the plurality of drive waveform generating circuits exceeds a prescribed tolerable level that is prescribed for each of the plurality of drive waveform generating circuits, wherein the control device selects a second drive waveform generating circuit which is different from the first drive waveform generating circuit, instead of the first drive waveform generating circuit, of the plurality of drive waveform generating circuits, in respect of at least a portion of the pressure generating elements, in such a manner that no drive waveform generating circuit in which the amount of momentary current consumption exceeds the prescribed tolerable value, of the plurality of drive waveform generating circuits, exists.