Appeal No. 1999-1854
Application No. 08/633,616
The claimed invention relates to a method and apparatus
for suppressing residual ink vibration after ink droplet
ejection from an ink jet printing head. More particularly,
Appellants indicate at pages 3 and 4 of the specification that
the residual vibrations in the deformable diaphragms used to
expel ink from a nozzle are dampened by applying a secondary
driving signal at a preselected period of time after the
primary ejection drive signal has been transmitted.
Claim 1 is illustrative of the invention and reads as
follows:
1. An ink jet head, comprising:
an ink nozzle for ejecting ink drops;
an ink chamber having at least one wall and a
volume and extending into communication with said
ink nozzle for storing ink;
an elastic diaphragm formed in said at least
one wall of said ink chamber;
a diaphragam drive circuit connected to said
diaphragm to selectively deform said diaphragm
and alter the volume of said ink chamber;
a substantially stationary wall disposed
externally to said ink chamber opposing said diaphragm
and a gap separating said stationary wall from said
diaphragm when said diaphragm is not deformed;
a signal generator in communication with said
diaphragm drive circuit for applying a charge signal
and a first discharge signal to said diaphragm drive
circuit to eject an ink drop from said nozzle;
a timer in communication with said signal
generator for timing a predetermined interval after
application of said charge signal; and wherein
3
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 Next
Last modified: November 3, 2007