Piezoelectric ink jet nozzle and ink jet printer

The invention discloses a piezoelectric type ink jet nozzle and an ink jet printer, and belongs to the technical field of ink jet printers. The spray head comprises a plurality of ink jet cavities; at least one piezoelectric element is arranged in each ink jet cavity, a resistance strain gauge is arranged on at least one position of the inner wall, located in the ink jet cavity, of the piezoelectric element and the outer wall, back to the ink jet cavity, of the piezoelectric element, and the resistance strain gauge and the piezoelectric element are electrically insulated. The spray head provided by the invention solves the problem that the spray head fault cannot be rapidly and accurately determined, and then the fault cannot be rapidly and effectively processed, and the piezoelectric type ink-jet spray head is provided with a piezoelectric element deformation detection structure, so that the fault reason that the spray head does not jet ink can be determined by detecting the deformation of the piezoelectric