To modify the mode of ink suction while securing the fixed amount of ink to be sucked, according to the conditions of nozzles and ink passages in a recording head.

A suction pump means is operated with the aid of a cam member. At the time of ordinary purging in suction operation, a second piston member is moved without stopping the cam member, and suction is performed at a stretch with a great suction force as shown in Figure (a). In automatic maintenance, the cam member is rotated at 10 degrees at a time at every 50ms, 100ms, or 200ms, and suction is performed with a relatively great suction force as shown in Figures (b), (c) and (d). In the replacement of an ink cartridge, the cam member is rotated at 10 degrees at a time at every 300ms, and suction is performed gradually with a small suction force as shown in Figure (e).