Ink jet printer control for precise performance - has profile giving optimum geometry of ink jet nozzle to regulate droplet delivery

摘要

The nozzle element of an ink jet printer is designed to allow accurate control of droplet delivery without exhibiting undue sensitivity. The nozzle element is provided by a glass tube (2) with a profiled nozzle section on one end (6). The surface of the tube (10) is coated with an electrode deposition and this forms part of an electro-mechanical pulse generator together with an outer tube (11) also with an electrode coating. When the generator is activated by signals applied(12, 13) to the electrodes, a pressure pulse is produced in the fluid within the nozzle section. The consistency and sharp cut off of the droplets produced depends largely upon the nozzle geometry. The nozzle exit angle should lie between 0 and 45 degrees and the inlet angle 20 to 60 degrees for optimum performance.