Abstract: An ink jet recording apparatus wherein ink drops can be controlled individually to assure high quality printing and adjustment in registration of ink nozzles in a drum circumferential direction can be performed at a sufficiently high resolution. The ink jet recording apparatus includes a plurality of nozzles arranged such that drops of ink may impinge in an overlapping relationship at a location on a record medium supported on a rotary drum, and adjustment in registration of the nozzles in a drum circumferential direction is performed by a registration adjusting system by which such adjustment is performed using a registration adjusting clock signal having a frequency higher than a picture element recording signal. An optimum phase between disintegration of an ink jet and a recording pulse signal is determined in accordance with current values detected by a current detector connected to an electrically isolated conductive drop catcher.

Abstract: A continuous ink jet recording apparatus which can record an image always with an appropriate density on any of various record media. A vibrating element driver drives a piezoelectric vibrating element in response to a disintegrating frequency signal from an oscillator to disintegrate a jet of ink from a nozzle. A multiplier multiplies picture element data of a line buffer by a density coefficient, and a pulse width modulator converts the picture element data from the multiplier into a charging controlling signal of the pulse width which increases in proportion to the number of ink drops per picture element. The charging controlling signal is applied via a high voltage switch to a controlling electrode, by which the in drops are charged in accordance with the charging controlling signal. A deflecting electrode deflects the charged ink drops.

Abstract: An ink jet recording apparatus of the continuous jet type and an automatic ink jet jetting axis adjusting method of the same wherein the position of an ink jet jetting axis or nozzle axis can automatically be adjusted to an optimum position by a deflecting electric field are disclosed. When a carriage is at its home position, jetting of ink from a nozzle is started, and an MPU changes over a change-over switch to a test signal generator side. The test signal generator generates a test signal, which is a sum of an amplified recording signal and a bias potential outputted from a bias power source, and applies the test signal to a controlling electrode. The MPU checks an output of a current detector (jet current) based on charged ink drops caught by a conductive drop catcher to discriminate the positional relationship between an ink jet jetting axis and a knife edge. The MPU then changes the bias potential of the bias power source in accordance with a result of the discrimination.