Patent attributes
An object is to provide a head drive unit that prevents an increase in viscosity of inks in nozzles even when a head is present outside an image forming region and also provide an inkjet printer, and the head drive unit includes: a drive signal output device 31 that outputs either a discharge signal or a meniscus oscillation signal to each head; a cycle generator 326 that generates a cyclic oscillation timing signal for the meniscus oscillation signal; an input interruption detector 324 that detects that input of a print timing signal is interrupted; and a drive signal selector 32 that selects the meniscus oscillation signal as a drive signal output from the drive signal output device and continuously applies the meniscus oscillation signal to all nozzles of each head in synchronization with an oscillation timing signal when interruption of the input of the print timing signal is detected.