Patent ID: 8186819
Filing Date: 2012-05-29
Classification: B41J

Abstract:
1. An image forming apparatus comprising: an inkjet head capable of ejecting ink from a nozzle; a first tank and a second tank that are separately provided from the inkjet head and each of which stores ink therein and supplies the ink to the inkjet head; a first flow path that connects the inkjet head to the first tank; a second flow path that connects the inkjet head to the second tank; a third flow path that connects the first tank to the second tank; and a negative pressure control mechanism that controls negative pressure in the first tank and the second tank; wherein the negative pressure control mechanism has a pump mechanism that provides a negative pressure in the first tank and the second tank, and the pump mechanism is provided at a position off of the first to third flow paths, and wherein the negative pressure control mechanism alternately switches a first phase in which a negative pressure is provided in the second tank and the first tank is opened to atmosphere so that the ink is delivered from the first tank to the second tank via the first flow path, the inkjet head and the second flow path, and a second phase in which a negative pressure is provided in the first tank and the second tank is opened to atmosphere so that the ink is delivered from the second tank to the first tank via the third flow path.