摘要 |
PROBLEM TO BE SOLVED: To predict occurrence of the failure of a piezoelectric element jetting ink in consideration of not only humidity but also other failure causes, thereby prompting replacement of a component before failure of the element and preventing a fatal defect such as a failure in jetting ink.SOLUTION: An inkjet head includes an ink-jetting piezoelectric element 2, and a monitoring piezoelectric element 3 for monitoring a failure of the ink-jetting piezoelectric element 2. The monitoring piezoelectric element 3 has tolerance against electrical and mechanical breakdown in repeated driving lower than the ink-jetting piezoelectric element 2 does. |