摘要:
An image forming apparatus includes a image bearing member having a photosensitive layer, a surface protection layer having fluorine resin material; a charging member contactable to the image bearing member to electrically charge the image bearing member, the charging member is capable of being supplied with an oscillation voltage, and wherein a peak-to-peak voltage of the oscillating voltage applied across a gap between a surface of the charging member and the surface of the image bearing member, is not less than twice a charge starting voltage of the image bearing member in the gap and not more than 1600 volt.
摘要:
A developing apparatus includes a developer carrying sleeve, opposed to an electrostatic image bearing member for carrying a developer; a regulating member for regulating an amount of developer on the developer carrying sleeve, wherein the regulating member cooperates with the developer carrying member to form a nip, and includes a rubber blade having a wear index of 0.03-0.15, and wherein the rubber blade is contacted to the developer carrying member with a contact pressure P (g/cm), wherein 10.ltoreq.P.ltoreq.60.
摘要:
A process cartridge includes an electrophotographic photosensitive member, a developer for developing a latent image formed on the electrophotographic photosensitive member, a developer remaining amount detecting member for detecting a remaining amount of developer in the developer, and a non-volatile memory for memorizing information corresponding to at least the print number of sheets and the developer remaining amount in such a manner that such information can be read out and re-written by an image forming apparatus. The present invention also provides and electrophotographic image forming apparatus to which such a process cartridge can be detachably mounted.
摘要:
A developing device includes a developer container for accommodating one component magnetic toner; a rotatable toner carrying member, faced to an image bearing member for bearing an electrostatic image to form a developing zone therebetween, for carrying the toner in the container; a magnet member in the toner carrying member; a regulating member, elastically urged to the toner carrying member to form a nip therebetween, for regulating a toner layer thickness on the toner carrying member; wherein the magnet member has a magnetic pole, upstream of the nip with respect to a movement direction of the toner carrying member, for supplying the toner in the container to the toner carrying member, and wherein the magnet member does not generate a magnetic field effective for chain erection of the toner in a range from an upstream end of the nip to a downstream end of the developing zone.
摘要:
The present invention relates to a developing apparatus in which, assuming that a tangent which is in contact with said detecting member on an opening portion side of a developing container in a vertical direction is a first tangent, and a tangent which is in contact with a rotating locus of a first agitating member on an opposite side of the opening portion in a vertical direction is a second tangent, the first tangent is positioned nearer to the opening portion than the second tangent, and a lower end of said partition member is provided between the first tangent and the second tangent.
摘要:
A developing apparatus includes a developer containing portion containing a developer having a weight average particle diameter of not more than 7 &mgr;m, a developer bearing member for bearing a developer, and an agitating member that agitates the developer contained in the developer containing portion. The agitating member is intermittently driven with respect to rotation of a developing sleeve. The agitating member is driven to rotate for one page every time the image forming apparatus performs a predetermined number of printing operations. A rod member having a crank-like shape may be used as the agitating member and both of the end portions serve as the center of rotation. By controlling the drive of the agitating member, it is possible to effectively adjust the supply of toner to the developing sleeve and prevent the density lowering phenomena caused due to inflow of a large amount of the new toner presented at the rear of the developing container. The agitating member may be positioned closest to the developing sleeve and may be arranged below the toner container. Accordingly, to these arrangements, the image density after printing a low print pattern can be prevented from being lessened to obtain a uniform image density even though a one-component magnetic developer having the weight average particle sized diameter of not more than 7 &mgr;m is used.
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 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 including a developer carrying member for carrying a developer, a magnet disposed in the developer carrying member, and an elastic regulating member contacting the developer carrying member to regulate a thickness of a layer of the developer formed on the developer carrying member. The developer carrying member has a roughened surface over a width thereof larger than a width of the portion of the elastic regulating member contacting the developer carrying member while the magnet forms a magnetic field in a marginal region of the roughened surface of the developer carrying member not contacting the elastic regulating member to remove magnetic developer.
摘要:
A charging system includes a rotatable member to be charged, and a rotatable charging member provided with electroconductive particles thereon and forming a nip part with the member to be charged and disposed in the nip part to charge the member to be charged. When the diameter of the member to be charged is defined as LD (mm) and the diameter of the charging member is defined as LC (mm), LD≦25 and LD×LC≧350. As a result,, in the charging system, and a process cartridge and an image-forming apparatus including such a charging system, an image-bearing member can be made small in diameter.