摘要:
A developing apparatus includes a developer bearing member for bearing and carrying developer to a developing area. A developer is borne on the developer bearing member, wherein the developer has a weight average particle size not exceeding 6.5 &mgr;m and contains an external additive of a charging polarity opposite to that of the developer. A voltage application device applies a voltage to the developer bearing member, wherein the voltage including at least a first voltage V1 for acting on the developer in a direction from the developer bearing member toward an image bearing member and a second voltage V2 for acting on the developer in a direction from an image bearing member toward said developer bearing member, and a charged potential VL of the image bearing member, a latent image potential VD a distance H between the developer bearing member and an image bearing member, and wherein the voltages V1 and V2 satisfy a following relationships: |V1−VL|/H≦3.7×10−6 V/m; and |V2−VD|/H≦2.9×10−6 V/m.
摘要:
The present invention relates to a development density adjusting method in which development density is adjusted by varying ratio of application time of a voltage having the first voltage value to application time of a voltage having the second voltage value in one period, and difference between a potential of the developer bearing member and a potential of the electrostatic latent image, when the voltage having the first voltage value is applied to the developer bearing member.
摘要:
When a user changes a density adjusting value (developing contrast), and even when variations in the usage state of process characteristics (of the photosensitive body and the developing device) of the cartridge change, the amount of recording agent consumed can be suppressed to be low, and a sharp line image can be recorded. An image forming apparatus of this invention includes an edge detecting portion for detecting an edge of image data, an image data correcting portion for correcting image data inside the edge so as to decrease its density, a laser driving circuit for forming an electrostatic latent image on a photosensitive body, and a correction value determining table for acquiring an instruction value for giving an instruction to correct a density contrast, wherein a correction condition for image data changes in accordance with an instruction value.
摘要:
When a user changes a density adjusting value (developing contrast), and even when variations in the usage state of process characteristics (of the photosensitive body and the developing device) of the cartridge change, the amount of recording agent consumed can be suppressed to be low, and a sharp line image can be recorded. An image forming apparatus of this invention includes an edge detecting portion for detecting an edge of image data, an image data correcting portion for correcting image data inside the edge so as to decrease its density, a laser driving circuit for forming an electrostatic latent image on a photosensitive body, and a correction value determining table for acquiring an instruction value for giving an instruction to correct a density contrast, wherein a correction condition for image data changes in accordance with an instruction value.
摘要:
A process cartridge detachably mountable to an image forming apparatus, wherein the image forming apparatus light emitting means and light receiving means cooperative with the light emitting means to detect amount of toner in a part of the process cartridge, the process cartridge includes an electrophotographic photosensitive member; process means actable on the electrophotographic photosensitive member; a toner container, adapted for being mounted in the part, for containing the toner to be used for developing a latent image formed in the electrophotographic photosensitive member; a light transmitting member, provided in the toner container, for transmitting light emitted from the light emitting means to permit detection of the amount of the toner in the toner container when the process cartridge is mounted to a main assembly of the image forming apparatus; a cover member movable between a protecting position for protecting the electrophotographic photosensitive member and a retracted position wherein the cover is retracted from the covering position; wherein upon movement of the cover member from the protecting position to the retracted position when the process cartridge is mounted to the main assembly, the cover member is retracted toward the toner container beyond a position of the light transmitting member.
摘要:
A developing apparatus for developing a latent image formed on an electrophotographic photosensitive member include a toner container for containing toner to be used for developing the latent image, a light transmitting member for transmitting light for detecting that an amount of the toner in the toner container is smaller than a predetermined level, a cleaning member for cleaning the light transmitting member, a stirring member reciprocating device for reciprocating a stirring member, and a cleaning member reciprocation device for reciprocating the cleaning member with a degree of displacement larger than that of the stirring member.
摘要:
A developing unit including a developer container for accommodating a developer, a first window portion which is formed in an upper portion of the developer container and through which light passes, a second window portion which is formed in a lower portion of the developer container and through which light passes, a first wiping member for wiping the first window portion, a second wiping member for wiping the second window portion, and a holding member for holding the first wiping member and the second wiping member at opposite ends of said holding member, wherein the holding member performs a reciprocating operation with respect to a supporting point.
摘要:
A memory medium is provided to a cartridge detachably mountable to an image forming apparatus. Into the memory medium, as information for performing charge control, information on the amount of usage of an image-bearing member and information on a charging alternating voltage (a threshold value for selection control of a charging peak-to-peak voltage Vpp) are written. The image forming apparatus includes a charging-bias power-supply circuit, on its body side, including AC oscillation output circuit capable of outputting two or more species of alternating peak-to-peak voltages and an AC detector for detecting an alternating current passing through the image-bearing member. Charge control is performed on the basis of a detected value detected by the AC detector and memory information for the cartridge, whereby good charge control space saving, and cost reduction of the power-supply circuit are compatibly realized.
摘要:
A memory medium is provided to a cartridge detachably mountable to an image forming apparatus. Into the memory medium, as information for performing charge control, information on the amount of usage of an image-bearing member and information on a charging alternating voltage (a threshold value for selection control of a charging peak-to-peak voltage Vpp) are written. The image forming apparatus includes a charging-bias power-supply circuit, on its body side, including AC oscillation output circuit capable of outputting two or more species of alternating peak-to-peak voltages and an AC detector for detecting an alternating current passing through the image-bearing member. Charge control is performed on the basis of a detected value detected by the AC detector and memory information for the cartridge, whereby good charge control space saving, and cost reduction of the power-supply circuit are compatibly realized.
摘要:
A charging apparatus includes a charging member, contactably provided to a member to be charged, for charging the member to be charged; a voltage application device for applying alternating voltages having different peak-to-peak voltages to the charging member; and a determination device for determining a peak-to-peak voltage to be applied to the charging member with respect to a second area of the member to be charged, on the basis of a peak-to-peak voltage corresponding to a minimum current which is not less than a predetermined current of alternating currents through the member to be charged when the alternating voltages having the different peak-to-peak voltages are applied to the charging member with respect to a first area of the member to be charged.