Three-color drum printer with specific relationship between transmission ratio drum radius and information carrier thickness

摘要

A color printer for printing a color image of sequential lines of three different base colors, with a drum having a length of sheet-like information carrier wrapped around it and secured thereto. A transmission means having a gear ratio is connected between a motor shaft and the drum for rotating the drum. The gear ratio of the transmission means, the drum radius and the thickness of the information carrier are so selected that for a whole number of revolutions of the motor shaft the drum moves a location on the information carrier a distance equal to 2( pi R)+x from the position at which the location was when the motor started revolving wherein R is equal to the sum of the radius of the drum and the thickness of the information carrier and x is equal to the distance between two successive lines of different base colors in the printed color image.