Ink drop writing system with nozzle drive frequency control

Claim 2

In an ink drop writing system of the type wherein ink under pressure is delivered to a nozzle, a transducer vibrates the nozzle as a function of drive signals supplied thereto, the nozzle emits an ink jet which breaks up into drops, a charging tunnel is positioned in the region at which the ink jet breaks up into the drops, the charging tunnel being adapted to respond to video signals to charge the drops passing therethrough as a function of said video signals, the improvement comprising: video pulse signal source means coupled to said charging tunnel for applying video signals thereto at a preselected first frequency; and nozzle drive means for applying drive signals to said transducer at a second frequency to vibrate said nozzle therewith, said second frequency being a function of said first frequency and the rise or fall time of said video pulse signals.

Claim 3

The arrangement as recited in claim 1 wherein said second frequency is higher than said first frequency.

Claim 4

In a ink drop writing system of the type wherein ink under pressure is delivered to a nozzle, a transducer vibrates the nozzle as a function of drive signals supplied thereto, the nozzle emits an ink jet which breaks up into drops, a charging tunnel is positioned in the region at which the ink jet breaks up into the drops, the charging tunnel being adapted to respond to video signals to charge the drops passing therethrough as a function of said video signals, the improvement comprising: video signal source means coupled to said charging tunnel for applying video signals thereto at a preselected first frequency; and nozzle drive means for applying drive signals to said transducer at a second frequency to vibrate said nozzle therewith, said second frequency being a function of said first frequency and the shape of said video signals, the duration of each video signal being characterized by a first time interval during which the level of the signal rises from a reference level to a selected level, a second time interval, following said first time interval, during which the signal level is at said selected level, and a third time interval, following said second time interval, during which said signal level falls from said selected level to said reference level, said first and third time intervals being definable as the rise and fall times of the signal, respectivEly, said second frequency being a function of at least said first frequency and said rise time.

Claim 5

In a ink drop writing system of the type wherein ink under pressure is delivered to a nozzle, a transducer vibrates the nozzle as a function of drive signals supplied thereto, the nozzle emits an ink jet which breaks up into drops, a charging tunnel is positioned in the region at which the ink jet breaks up into the drops, the charging tunnel being adapted to respond to video signals to charge the drops passing therethrough as a function of said video signals, the improvement comprising: video signal source means coupled to said charging tunnel for applying video signals thereto at a preselected first frequency; and nozzle drive means for applying drive signals to said transducer at a second frequency to vibrate said nozzle therewith, said second frequency being a function of said first frequency and the shape of said video signals, the duration of each video signal being characterized by a first time interval during which the level of the signal rises from a reference level to a selected level, a second time interval, following said first time interval, during which the signal level is at said selected level, and a third time interval, following said second time interval, during which said signal level falls from said selected level to said reference level, said first and third time intervals being definable as the rise and fall times of the signal, respectivEly, said second frequency being a function of at least said first frequency and said rise time.

Claim 6

The arrangement as recited in claim 3 wherein Fd Fv/1 - Fv Tr, where Fv and Fd are the first and second frequencies respectively, and Tr is said rise time.

Claim 7

The arrangement as recited in claim 3 wherein the second frequency, definable as Fd is higher than said first frequency, and Fd.Te is not less than 1, where Te represents said second time interval.

Claim 8

The arrangement as recited in claim 3 wherein Fd Fv/(1-Fv.Tx), where Fv and Fd are the first and second frequencies respectively, and Tx is the greater of said rise time and fall time.

Claim 9

The arrangement as recited in claim 6 wherein the second frequency, Fd is higher than said first frequency and Fd.Te is not less than 1, where Te is said second time interval.

Claim 10

The arrangement as recited in claim 3 wherein Fd Fv(1-Fv.Tx) where Fv and Fd are the first and second frequencies respectively, and Tx is the greater of said rise time and fall time.