Abstract: An continuous ink jet printer projects a stream of evenly spaced ink drops toward a substrate and controls placement of the ink drops on the substrate by selectively charging the individual ink drops and passing the charged ink drops through an electric field to control placement of said charged ink drops on a substrate. The printer may be used to print either single or multiple lines of print in a single stroke. A stroke consists of a single column from all lines and can have adjacent drops printed in alternating lines to reduce drop interaction. Each line of print in the stroke having N virtual print positions, at least some of which are being divided into pairs of adjacent positions. Each pair of adjacent positions has a first print position and a second print position. The printer includes a controller having a plurality of first and second look-up tables, each of which is associated with a different one of said pairs of adjacent print positions.

Abstract: An continuous ink jet printer projects a stream of evenly spaced ink drops toward a substrate and controls placement of the ink drops on the substrate by selectively charging the individual ink drops and passing the charged ink drops through an electric field to control placement of said charged ink drops on a substrate. The printer may be used to print either single or multiple lines of print in a single stroke. A stroke consists of a single column from all lines and can have adjacent drops printed in alternating lines to reduce drop interaction. Each line of print in the stroke having N virtual print positions, at least some of which are being divided into pairs of adjacent positions. Each pair of adjacent positions has a first print position and a second print position. The printer includes a controller having a plurality of first and second look-up tables, each of which is associated with a different one of said pairs of adjacent print positions.

Abstract: A flow rate control system is disclosed for measurement of ink flow through an ink jet system. The flow rate control system receives an error signal indicative of deviation of flow rate from a set value. The system includes proportional (P), integral (I) and derivative (D) control to generate a control signal based on the magnitude and sign of the error signal. The control signal is used to control the on-time of an ink make-up valve which adds make-up ink to the system as ink is needed to maintain satisfactory operation. In a preferred embodiment, the PID controller has noise reduction capability through the use of clippers and low pass filters. In addition, conditional summation may be employed to minimize "hunting" at low error signal levels.