US 7,530,653 B2
Recording head and recorder comprising such recording head
Nobuyuki Hirayama, Fujisawa (Japan)
Assigned to Canon Kabushiki Kaisha, Tokyo (Japan)
Filed on May 23, 2005, as Appl. No. 11/134,418.
Application 11/134418 is a continuation of application No. PCT/JP03/15273, filed on Nov. 28, 2003.
Claims priority of application No. 2002-348725 (JP), filed on Nov. 29, 2002.
Prior Publication US 2005/0206685 A1, Sep. 22, 2005
Int. Cl. B41J 29/38 (2006.01)
U.S. Cl. 347—9  [347/12] 20 Claims
OG exemplary drawing
 
1. An inkjet recording head having a plurality of heaters configured to eject ink, a control circuit configured to supply print signals to time-divisionally drive respective heaters in accordance with an image signal, and a plurality of switching circuits, connected in series to the respective heaters, configured to control energization of the corresponding heaters in accordance with the print signals supplied from the control circuit, the ink jet recording head comprising:
a plurality of constant current sources, each being connected to one of plural groups of the heaters and the switching circuits in series, configured to supply a constant current to a heater belonging to a group, wherein in each group, plural sets of heaters and switching circuits connected in series to the respective heaters are connected in parallel, and a plurality of groups and the constant current sources connected to the respective groups are connected in parallel to a pair of power supply lines from an external power supply; and
a current control circuit configured to control the constant currents supplied from said constant current sources,
wherein each of the plurality of switching circuits has a MOS transistor to energize a corresponding heater in a group during the print signal being supplied from the control circuit, and each of said plurality of constant current sources includes a MOS transistor to supply the constant current that is adjusted by said current control circuit to the corresponding heater belonging to the group to which each of said plurality of constant current sources is connected.