| 摘要 |
FIELD: printing industry.SUBSTANCE: present invention refers to an imaging device, such as a copying machine and a laser-beam printer. The imaging device comprises a electrically conductive intermediate transfer ribbon and a power supply for application of voltage to a secondary transfer roller for passage of electrical current from the secondary transfer roller to a number of photosensitive drums through the intermediate transfer ribbon, thereby performing a primary transfer of toner images from the number of photosensitive drums onto the intermediate transfer ribbon. The imaging device comprises an image-carrying element configured to carry a toner image; a rotated infinite intermediate transfer element and power supply configured to apply voltage for transferring of the toner image from the image-carrying element onto a transfer material through the intermediate transfer element; the intermediate transfer element has an electrical conductance, and the power supply applies a voltage, which has a polarity opposite to a normal polarity of a toner charge to perform the primary transfer of the toner image from the image-carrying element onto the intermediate transfer element by passage of electrical current in the circular direction in relation to the intermediate transfer element, and applies the above voltage of the opposite polarity to perform the secondary transfer of the toner image, which has been transferred on the intermediate transfer element after the primary transfer, onto the transfer material.EFFECT: supplying electrical current in the circular direction of the intermediate transfer ribbon from the current supply element eliminates the necessity to prepare the power supply for each of the number of primary transfer elements, thereby enabling the primary and secondary transfers by means of the same current supply element and consequently reducing the price and dimensions of the imaging device.33 cl, 16 dwg, 2 tbl |
