US 12,034,416 B2
Head unit and liquid discharge apparatus
Shunsuke Yamamichi, Nagano (JP); and Yusuke Matsumoto, Nagano (JP)
Assigned to Seiko Epson Corporation, Tokyo (JP)
Filed by SEIKO EPSON CORPORATION, Tokyo (JP)
Filed on Nov. 29, 2021, as Appl. No. 17/456,663.
Claims priority of application No. 2020-199485 (JP), filed on Dec. 1, 2020.
Prior Publication US 2022/0169018 A1, Jun. 2, 2022
Int. Cl. B41J 2/045 (2006.01); B41J 29/377 (2006.01); H03F 3/217 (2006.01)
CPC H03F 3/217 (2013.01) [B41J 2/04541 (2013.01); B41J 2/0455 (2013.01); B41J 2/04581 (2013.01); B41J 29/377 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A head unit having a first driving element group driven by a first driving signal and discharging a liquid in response to drive of the first driving element group, comprising:
a substrate that propagates the first driving signal;
a first driving circuit disposed on the substrate and outputting the first driving signal;
a heat sink fixed to the substrate; and
a plurality of heat conductive elastic bodies positioned between the substrate and the heat sink, wherein
the first driving circuit includes a first integrated circuit that outputs a first gate signal based on a first reference driving signal that is a reference of the first driving signal, a first amplifier circuit including a first transistor driven by the first gate signal, and a first smoothing circuit that has a first inductor element, smoothes output from the first amplifier circuit, and outputs the first driving signal,
a first heat conductive elastic body among the plurality of heat conductive elastic bodies is positioned between the heat sink and the first integrated circuit, and is in contact with the heat sink and the first integrated circuit,
a second heat conductive elastic body among the plurality of heat conductive elastic bodies is positioned between the heat sink and the first transistor, and is in contact with the heat sink and the first transistor,
the substrate has a first side and a second side which are positioned facing each other, and a third side and a fourth side which are shorter than the first side and positioned facing each other,
the first integrated circuit, the first transistor, and the first inductor element are positioned in order of the first integrated circuit, the first transistor, and the first inductor element along a direction from the first side toward the second side,
the heat sink has a fifth side and a sixth side which are positioned facing each other, and is positioned such that the fifth side and the sixth side extend along the first side and a shortest distance between the fifth side and the first side is shorter than a shortest distance between the sixth side and the first side, and
a shortest distance between the first integrated circuit and the fifth side is longer than a shortest distance between the first transistor and the sixth side in a plan view when viewed from a normal direction of the substrate.