Patent ID: 8870333
Filing Date: 2014-10-28
Classification: B41J

Abstract:
1. A printing apparatus comprising: a print head comprising (a) a printing element substrate having a printing element array in which a plurality of printing elements for generating heat energy are arranged in a predetermined direction, a first temperature sensor for detecting a temperature of printing elements positioned at a first position of the printing element array in the predetermined direction, and a second temperature sensor for detecting a temperature of printing elements positioned at a second position of the printing element array which is different from the first position in the predetermined direction, and (b) an electric line member which is electrically contacted with the printing element substrate, and is provided with a driving line for applying energy to drive the plurality of printing elements, a first output line for transmitting a signal from the first temperature sensor to the printing apparatus, and a second output line, being longer than the first output line, for transmitting a signal from the second temperature sensor to the printing apparatus; a first obtaining unit for obtaining information regarding a temperature of the printing element substrate by using at least one of the signals transmitted from the first temperature sensor and the second temperature sensor; a second obtaining unit for obtaining a value regarding an amount of ink ejection per unit time from the print head; and an ejection controlling unit for controlling ejection of ink by applying a driving pulse to the plurality of printing elements based on the temperature indicated by the information obtained by the first obtaining unit, wherein (i) in a case that the value obtained by the second obtaining unit is less than or equal to a predetermined threshold value, the first obtaining unit obtains the information regarding the temperature of the printing element substrate based on both of the signal transmitted by the first output line from the first temperature sensor and the signal transmitted by the second output line from the second temperature sensor, and (ii) in a case that the value obtained by the second obtaining unit is larger than the predetermined threshold value, the first obtaining unit obtains the information regarding the temperature of the printing element substrate based on the signal transmitted by the first output line from the first temperature sensor, without using the signal transmitted by the second output line from the second temperature sensor.