摘要:
An electrophotographic apparatus includes a photoconductor drum, also known as an electrostatic latent image holding member, with a magnet placed therein. An electrostatic latent image is formed on the magnetic drum. Then, the drum is brought into contact with a magnetic developer, or toner, in a developer reservoir to have the magnetic developer attached to the photoconductor drum surface by a magnetic force. A removing roller, having an AC voltage applied thereto, is passed in close vicinity of the magnetic drum with the resultant development of images because toner remains at image areas only. In the electrophotographic apparatus, the photoconductor drum, the removing roller or both include two magnetic poles. A device for increasing friction force of the surface of the photoconductor drum, of the removing roller or both may also be provided.
摘要:
A printing apparatus having almost the same scale and function as printing apparatuses the usable maximum paper size of which is equivalent to A-4 size can print an image on a paper the size of which is larger than A-4 as necessary. A printing mechanism section (101) and a paper feed mechanism section (180) print an image according to printing data on one side of a paper which can be an expansion printing paper folded once or more times and developable after printing. The paper feed mechanism section (180) reverses a paper and feeds the reversed paper to the printing mechanism section (101). By using a printing mode selecting function of a printer driver (410), a predetermined printing mode is selected from printing modes in which the image is printed in different printing forms on the paper. A printing controller (150) for printing the image on the paper controls the operation of the printing mechanism section (101) and the paper feed mechanism section (180) according to the instruction of the selected printing mode, divides the image in a paper expansion printing mode in which the image is printed on both sides of the expansion printing paper, and prints the divided images on both sides of the expansion printing paper.
摘要:
An electrophotographic method and an apparatus employed for effecting the method, in which a photoreceptor drum having a fixed magnet member in it is employed. After forming an electrostatic latent image on the surface of the photoreceptor drum, the photoreceptor surface is brought into contact with the magnetic developing material within a developing material hopper so as to attract the developing material onto the surface of the photoreceptor drum by magnetic force. When the photoreceptor surface further passes an electrode roller, the toner remains only at the image portion for development into a visible toner image. As a force for removing the magnetic developing material from the photoreceptor surface, a resultant force of a magnetic force connecting the photoreceptor drum and the electrode roller and an electrostatic force connecting the photoreceptor drum and the electrode roller, is employed. Thus, the present invention provides the novel electrophotographic method and the apparatus for executing the method, which is simple in construction and a compact in size, and capable of providing images with a high resolution.
摘要:
An image heating device comprises a cylindrical heating roller with a Curie temperature of 210° C., a magnetization coil for magnetizing the heating roller with an alternating magnetic field, which is arranged inside the heating roller, and a nip portion for heating a recording material that carriers a toner image with heat from the heating roller, while the recording material is being conveyed along said nip portion. The ratio between the amount of heat generated in said heat-generating member at Curie temperature or higher to the amount of heat generated at room temperature in said heat-generating member is not more than ½. With this configuration, the heating roller can regulate its own temperature to stabilize at a temperature that is suitable for fixing, and the problems of partial overheating or underheating, unstable heat generation, or damage of the device can be eliminated.
摘要:
In a color image forming apparatus, a plurality of image forming units 3Y, 3M, 3C and 3K, which correspond to a plurality of colors and with each unit including a developing device and a photosensitive drum, are retained so as to define a cylinder. The color image forming apparatus includes: a conveying apparatus for conveying the plurality of image forming units around the main axis of the cylinder between an image forming position and a waiting position by simultaneously rotating all image forming units; an exposing device 6 for exposure of the photosensitive drum of the image forming unit that is in the image forming position 10; a transfer apparatus 5, which contacts a transfer belt 50 with the photosensitive drum 30 of the image forming unit that is in the image forming position, and when the image forming unit that is in the image forming position is switched, successively transcribes the toner images of all colors formed on the photosensitive drums onto the transfer belt, superimposes the toner images of all colors and forms a colored toner image on the transfer belt; and a transfer belt driving apparatus for driving the transfer belt at a constant speed. When a second color image is formed after a first color image, the first toner image color of the second color image is formed on the transfer belt by using the image forming unit of the last color added to the first color image. The exposing device includes a light source accommodated by the inner portion of the cylinder defined by the image forming units.
摘要:
An electrophotographic method, and an apparatus for performing the method, which is simple in construction, compact in size, and capable of providing images with a high resolution employs the use of a photoreceptor drum having a fixed magnet member therein. After forming an electrostatic latent image on the surface of the photoreceptor drum, the photoreceptor surface is placed in contact with magnetic developing material within a developing material hopper so as to attract the developing material onto the surface of the photoreceptor drum by magnetic force. When the photoreceptor surface further passes an electrode roller, the toner remains only at the image portion for development into a visible toner image. To remove the magnetic developing material from the photoreceptor surface, a magnetic force connecting the photoreceptor drum and the electrode roller and an electrostatic force connecting the photoreceptor drum and the electrode roller are employed.
摘要:
A color electrophotographic apparatus employing a plurality of image forming units each including a photoreceptor and a corona charger, and using toner. In the apparatus, the image forming units are arranged to be displaceable, with an exposure position of an exposure device and a transfer position of a transfer paper holding member being fixed. During image formation, the image forming unit is moved to a predetermined position, and the obtained color image transferred onto paper sheet on a transfer paper holding member. Each of the image forming unit has a first image forming position confronting the transfer paper holding member, and a second image forming position different from the first image forming position.In the color electrophotographic method of the present invention, when a photoreceptor using time in each single color image forming process for the color image formation is represented by T, and time for electrostatically resting the photoreceptor until the next use of the photoreceptor is denoted by t, the process in the relation of T
摘要:
An image heating device comprises a cylindrical heating roller with a Curie temperature of 210.degree. C., a magnetization coil for magnetizing the heating roller with an alternating magnetic field, which is arranged inside the heating roller, and a nip portion for heating a recording material that carries a toner image with heat from the heating roller, while the recording material is being conveyed along said nip portion. The ratio between the amount of heat generated in said heat-generating member at Curie temperature or higher to the amount of heat generated at room temperature in said heat-generating member is not more than 1/2. With this configuration, the heating roller can regulate its own temperature to stabilize at a temperature that is suitable for fixing, and the problems of partial overheating or underheating, unstable heat generation, or damage of the device can be eliminated.
摘要:
A color electrophotographic apparatus for forming color images has advantages of compact and simple construction, easy positioning of an exposure position and easy inspection. The apparatus includes a plurality of rotatable image forming units corresponding to the number of colors, each of the units including a pivotable photosensitive member on which a toner image is formed and a developing device containing a color toner. The apparatus further includes an exposure device for exposing a toner image by emitting a signal light from outside of the image forming units and a mirror for reflecting the signal light to an exposure position, the mirror being placed in the neighbor of a rotation axis.
摘要:
A color electrophotographic apparatus arranged as follows is disclosed. A plurality of image forming units (1BK, 1C, 1M, 1Y) each including a developing device having an electrostatic latent image holding member and toner of a different color are employed. Each of the image forming units is arranged to be displaceable so as to be moved to the same image forming position for positioning. At the image forming position, the image forming unit is exposed to light image by an exposure device for image formation, with its toner image being transferred onto a transfer material through a confronting transfer transport device. The image forming unit at the image forming position is sequentially exchanged, and by the reciprocation of the transfer material through the transfer/transport device, toner images of respective colors are transferred as overlapped through positioning for coincidence, onto the same transfer material.