According to one embodiment, an inkjet head includes a mask part which covers a periphery of an actuator part in a state where a nozzle hole is exposed to outside and a peripheral edge part of which is opposite to an opening peripheral edge part of a frame part at other end while a gap is kept, and the gap between the peripheral edge part of the mask part and the opening peripheral edge part of the frame part at the other end is sealed with a seal agent having thermal insulation properties.
1. An inkjet head comprising: a frame part, made of metal, including a side wall used also as a thermal radiation part; an ink supply pipe to supply ink into an inside from an opening of the frame part at one end; an actuator part which is provided at an opening of the frame part at the other end and includes a piezoelectric element to eject ink from a nozzle hole of an ink chamber facing outside in response to an external signal; a drive IC directly contacting an inner surface of the side wall of the frame part, said drive IC for driving the piezoelectric element; a mask part, made of metal. which covers a periphery of the actuator part in a state where the nozzle hole is exposed to the outside and a peripheral edge part of which is opposite to an opening peripheral edge part of the frame part at the other end while a gap is kept therebetween; and a seal agent which directly seals the gap between the mask part and the part and has thermal insulation properties.
2. The inkjet head of claim 1 , wherein a pressure releasing part capable of releasing inner pressure to outside atmosphere is provided in the side wall of the frame part.
3. The inkjet head of claim 2 , wherein the pressure releasing part is a screw unit including a screw hole and a screw threaded in the screw hole.
4. The inkjet head of claim 3 , wherein a protuberant wall is provided around the pressure releasing part.
5. The inkjet head of claim 4 , wherein the protuberant wall has an annular shape to surround the pressure releasing part.
6. The inkjet head of claim 5 , wherein a top part of the protuberant wall has a uniform height.
7. The inkjet head of claim 2 , wherein the pressure releasing part is a hole having a diameter of 1 mm or less.
8. The inkjet head of claim 7 , wherein a protuberant wall is provided around the pressure releasing part.
9. The inkjet head of claim 8 , wherein the protuberant wall has an annular shape to surround the pressure releasing part.
10. The inkjet head of claim 9 , wherein a top part of the protuberant wall has a uniform height.