IMAGE FORMING DEVICE Russian patent published in 2016 - IPC G03G15/16 

FIELD: physics.

SUBSTANCE: present group of inventions includes image forming devices. An image forming device comprises an image bearing element for transferring a toner image, an intermediate transfer element for transferring the toner image transferred by the image bearing element in a primary transfer position, a transfer element for transferring the toner image from the intermediate transfer element to a recording material in a secondary transfer position, a DC voltage element configured for contact with the outer peripheral surface of the intermediate transfer element and electrically connected between the intermediate transfer element and the ground potential to maintain predetermined voltage by passing current through it; a power supply for generating both a secondary transfer electric field in the secondary transfer position and a primary transfer electric field in the primary transfer position by applying voltage on the transfer element for passing current through the DC voltage element, a detection session for detecting current flowing through the transfer element, an execution section for executing a test mode, wherein test voltage is applied to the transfer element by the power supply to detect current by the detection section, when there is no recording material in the secondary transfer position, and a controller for controlling voltage to be applied to the transfer element by the power supply, based on current detected by the detection section in the test mode, when there is a recording material in the secondary transfer position, wherein the controller controls the test voltage applied by the power supply such that the DC voltage element maintains the predetermined voltage during the test mode.

EFFECT: designing the structure wherein the predetermined voltage is generated in an intermediate transfer element by a DC voltage source, which enables to avoid the problem where the proper voltage cannot be obtained during the test mode in which test voltage is applied.

20 cl, 9 dwg