摘要:
An image forming apparatus includes: an image support medium; a charging member for charging the surface of the image support medium in contact with the surface of it; an exposure device for irradiating with light the surface of the image support medium charged by the charging member to form a static latent image; a developing device for supplying developer to the static latent image formed on the image support medium to develop the latent image and for removing the leftover developer on the image support medium; a transfer device for transferring the developer image, which has been developed on the image support medium by the developing device, to a member to be transferred; and a scraping member for scraping foreign matter such as dust and paper particles on the image support medium. The image forming apparatus is constructed such that the charging member causes the developer to adhere to the scraped foreign matter, and then the foreign matter is collected by the developing device through the image support medium. The scraping member is held by a holder which has an opening for allowing the foreign matter to pass through into the charging member housing.
摘要:
An image forming apparatus adopting a non-magnetic one component developing system is arranged such that a charge brush and a developing roller are aligned along the circumference of a photoreceptor drum, that is rotatably driven, in order from an upstream side in a rotating direction of the photoreceptor drum. A transfer roller is placed opposing the photoreceptor drum with a sheet transportation path in-between. The charge brush, the developing roller and the transfer roller are rotatably driven while contacting the photoreceptor drum respectively. A photoconductive layer of the photoreceptor drum is made of an organic photoconductive material, and a coefficient of friction of the photoreceptor drum and the developing roller is selected to be not more than 0.5. As this eliminates the irregularity in rotary movement of the photoreceptor, offers a quality image and reduces a driving force for the photoreceptor drum, an apparatus of a light weight and high cost can be achieved.
摘要:
A charger performs corona discharge by applying a voltage to a discharging electrode. The charger includes an electrode plate formed in the shape of a panel on the discharging electrode, a plurality of projecting portions disposed in an end portion of the electrode plate, and a plurality of projection groups formed in each of the projecting portions such that the projection groups are adjacent to each other in a thickness direction of the electrode plate.
摘要:
A charger charges a recording medium before irradiation of light to form an electrostatic latent image by irradiating light as an optical image onto a surface of the recording medium. The charger includes a discharging electrode having a plurality of projections for generating corona discharge to charge the recording medium surface, a conductive shield case having an opening face opposite to the recording medium and opposed to the discharging electrode, a holding member for holding the discharging electrode in the shield case in a state in which the discharging electrode is electrically insulated from the shield case, a conductive grid electrode electrically insulated and held between the discharging electrode and the recording medium, and a power supplying device for supplying a high voltage for discharge to the discharging electrode and setting a ratio of electric currents flowing through the grid electrode and the shield case such that these electric currents are approximately equal to each other. One form of the charger controllably moves the discharger electrode toward the recording medium for setting the value of the electric currents flowing through the grid electrode and the shield case until they are both equal to a predetermined reference value.
摘要:
A developer cartridge for image forming apparatuses which performs development to form images with non-magnetic, one-component type developer. The cartridge includes a developing roller for supplying developer to a photoconductor drum, a developer feed roller in non-contact with the developing roller for supply developer to the developing roller, and a developer-layer thickness control member for controlling the thickness of the developer layer on the developing roller. The developer feed roller is shaped as a regular polygonal prism. Since no recesses are formed in the surface of the regular polygonal prism, driving torque does not increase when developer is scrubbed from the prism, thus ensuring consistent operation and improved image quality. Non-magnetic, one-component type developer is compressed onto the developing roller by supplying the developer via the developer feed roller into a bottleneck between the developing roller and a developer applying member. The amount of developer which passes through the bottleneck onto the developing roller is controlled by a temporary reservoir, the pressurization thereof ensuring application of the developer to the developing roller. A control roller may be used against the developing roller to lower friction of developer, thereby preventing deposition of developer on the control roller while establishing a consistent amount of developer on the developing roller.
摘要:
An electrophotography developing apparatus has been developed which can protect a developer holder and a layer thickness control member from damage. The device also prevents internal scattering of the developer while preventing a surplus supply of the developer to both ends on the peripheral surface of the developer holder. The unique advantages of the invention are derived through the utilization of sealing members having different elastic properties, which assume both bulk removal of excess developer while providing the needed uniform developer thickness. Another embodiment of the invention has the width of the layer thickness control member in a longitudinal direction set wider than the width of the developer holder in a longitudinal direction, and both side edges of the layer thickness control member are positioned outside both side edges of the developer holder. Proper sealing is assured by having the inner side edges of the sealing member positioned inside the side edges of the developer holder and outside the side edges of the image area of the image holder.
摘要:
For input image data (`A`) before conversion, each pixel is converted into N (=3) parts. In this case, the three sub-pixels of data corresponding to a recording pixel (black pixel) are converted into recording sub-pixels on both sides of the three (`B`). This eliminates the density variation within a single pixel. Therefore, it is possible to reduce the dot spacing at slanted area, for example, and hence eliminate jaggies, providing a reproduced image easily recognized.
摘要:
A developing apparatus which is equipped with a developer control member for controlling the developer on a developer supporter to a prescribed thickness, and which uses a one-component developer, characterized in that recessed sections are formed at the surface of the developer supporter to receive the developer, and the density .alpha. of particles of the developer which enter the recessed sections and the nip width L1 between the developer control member and the developer supporter satisfy the relationship: 3
摘要:
A developing device attachable to and detachable from a printer using a non-magnetic monocomponent developer. Two different voltages are applied respectively to a developing roller and a toner layer thickness regulating device from a power source of the apparatus main body side through a terminal and a contacting spring. A voltage is applied directly to the developing roller from the contacting spring whereas a Zener diode is provided in a path connecting the contacting spring and toner layer thickness regulating device to apply another voltage to the toner layer thickness regulating device. The voltage applied to the toner layer thickness regulating device is dropped below the power supply voltage by the Zener voltage when a low-printing-ratio image is produced. Thus, the number of the terminals connecting the apparatus main body and developing device is reduced to one. Accordingly, defective connections at the contacting portions of the terminal can be prevented and the manufacturing costs can be reduced while a satisfactory image is produced.
摘要:
A blade cleaning jig includes a cleaning portion and a gripping portion. The cleaning portion includes a support body of stainless steel or the like and polishing tape provided on the upper face of this support body, and moreover a cushioning material is inserted between the support body and the polishing tape. A protective member for preventing damage to the surface of a developer roller is attached to the entire lower face of the support body. This protective member is attached bent at a circumferential end portion such that the protective member covers from the lower face of the support body via a circumferential edge portion to an upper face circumferential edge portion.