To transmit heat generated from a circuit element 27 to a radiator, and to efficiently diffuse it without giving unnecessary stress to a flexible wiring member 23 mounted with the circuit element 27.
The circuit element 27 arranged in the flexible wiring member 23 is stored in a recess 48 of a dissipation coupler 45 having turnable spindles 45a at both ends, and the dissipation coupler 45 is fixed to the wiring member 23. A pair of support pieces 45a of the radiator 44 having a dissipation part 44b, which is positioned outside the side wall 3a of a head holder 3 are made to face the inside of the head holder 3. Bearings 46 disposed in the pair of support pieces 45a support the turnable spindles 45a of the dissipation coupler 45 so as to be turnable. Since the dissipation coupler 45 is fitted along a pull angle of the flexible wiring member 23 extending from a discharge head 4 to a circuit board 30, unnecessary stress is not given to the flexible wiring member 23.
Tadashi Higashino
Hiroyuki Nishi