Abstract: An image printing apparatus for forming an image on a printing medium includes: a printing head including two ink chambers and a shutter; a heater provided under the two ink chambers; a charging electrode provided between the printing medium and the two ink chambers; a back electrode provided on a side of the printing medium which is opposite a side on which the image is formed; a controller associated with the shutter, the heater and the charging electrode.

Abstract: The invention provides an ink sheet transfer control apparatus which can transfer an ink sheet stably without requiring any complex structure. A CPU drives and controls a grid motor so that recording paper can be transferred at a constant speed with the ink sheet and the recording paper pressed in contact with each other by a thermal head and a platen. Then, the CPU drives an ink motor with an arbitrarily determined voltage Vi, and measures a current Ig then flowing through the grid motor. The CPU determines such an optimum drive voltage Vir of the ink motor that a specified tension is developed to the ink sheet in printing operation, based on the measured current Ig, and drives the ink motor with the optimum drive voltage Vir. Characteristics of print drive system are detected by measuring the current Ig flowing through the grid motor, so that the print drive system can be controlled with simple construction.

Abstract: In response to a vertical synchronizing signal generated from a vertical synchronizing signal generator, a microcomputer forms a predetermined image on a print sheet using a printer head on the basis of image data applied from an image memory. The microcomputer controls the rotation of a motor so that the move position of the print sheet is set to a predetermined position with a vertical synchronizing signal as the reference after an edge of the print sheet is detected by a sheet sensor.