Authors: K.H. Yoon, Y.W. Park, N.W. Wereley, Y.W. Park
Affilation: Chungnam National University, Korea
Pages: 220 - 223
Keywords: magnetostriction, leakage, dropet, frequency, back pressure
One of the challenges is to design a proper inkjet printhead for demanding trend. Current inkjet printheads are mostly based on either piezoelectricity or heat. This paper presents an inkjet printhead using a magnetostrictive principle. Even though successful ejection of a fluid was possible by using the 1st MagJet, some problems arise such as fluid leakage and low frequency operation. The redesign of the 1st MagJet is focused on overcoming those problems: one with structural redesign of printhead, and the other with usage of back pressure. The leakage can be prevented through the structural redesign, but the operational improvement is still limited. Air comes in and remains in the nozzle after one ejection of fluid is made. It is the reason why the 1st MagJet is operated at a frequency of upto 200 Hz. A back pressure is used with the redesigned MagJet, operated at a frequency of upto 1.5 kHz. Fig. 2 shows the detailed procedure for one droplet ejection. Fig. 3 shows the droplet sizes versus operational frequency (100~800 Hz). The flow rate from the back pressure controller ranges from 100 to 550 nL/s depending on the operational frequency.