Abstract: An image-forming apparatus is provided which has a photosensitive member having improved temperature characteristics and improved electric properties and an ozoneless charging system in combination, and employs neither a heater nor a cleaning roller. In the apparatus, a charging member having a cylindrical multipolar magnetic body of 500 G or stronger and a magnetic brush layer formed from a magnetic powder on the peripheral surface of the magnetic body is allowed to rub the surface of a charging object in a reverse direction at a movement speed ratio of not less than 110% to charge the charging object. The charging object is a photosensitive member having a photoconductive layer composed of non-single-crystal silicon. The photoconductive layer contains hydrogen at a content ranging from 10 to 30 atomic %, and Si--H.sub.2 /Si--H at a ratio ranging from 0.2 to 0.5, having density of state ranging from 1.times.10.sup.14 cm.sup.-3 to 1.times.10.sup.16 cm.sup.

Abstract: A charging member contactable to a member to be charged and capable of being supplied with a voltage to charge the member to be charged, the charging member including a core member having a stepped portion to provide a smaller diameter portion at an end portion side than at a longitudinally central side; and an elastic member supported by the core member, the elastic member covering the stepped portion.

Abstract: A charging member includes a conductive substrate and a surface layer which is to be brought into contact with a member to be charged. On the surface layer a raised fiber entangled material is provided.

Abstract: An apparatus for applying an electrical charge to a charge retentive surface by transporting ions through an electrically biased ionically conductive liquid and transferring the ions to the member to be charged across the liquid/charge retentive surface interface. The electrically biased ionically conductive liquid medium is brought into contact with the photoreceptor by placing a hydrophilic material imbibed with the ionically conductive liquid in contact with the photoreceptor. The hydrophilic material is partially surrounded by a pair of elongated blade elements as well as a pair of end seal elements for providing a sealed structure for containing the hydrophilic material A voltage is applied to the ionically conductive liquid medium while translating or rotating the charge retentive surface past the ionically conductive medium, thereby enabling the transfer of ions to the charge retentive surface A support blade may be provided for urging the donor blade into contact with the photoreceptor.

Abstract: A charging device includes a charging member contactable to said member to be charged to charge a member to be charged. Wherein a voltage is applicable to said charging member; a resistor provided in a charging circuit for applying the voltage to said charging member; wherein said resistor has a resistance not less than 0.5 times a resistance of said charging member; wherein a combined resistance of said charging circuit and said charging member is not more than 10.sup.7 .OMEGA..

Abstract: A charging member for charging a member to be charged includes a base member: a surface elastic member supported by the base member, the elastic member comprises a foamed member and a coating layer covering the foamed member; wherein a surface of the charging member has an Asker-C hardness of not more than 55 degrees and an international rubber hardness (IRHD) of not more than 80 degrees.

Abstract: A charging member is provided comprising an electroconductive substrate having sequential overlying layers of an elastic material comprising an epichlorohydrin rubber and a surface layer comprising an aqueous polyurethane resin. The resulting composite charging member represses adhesion of toner particles and dirt to the surface thereof, exhibits improved durability, and prevents lowering of the charging potential in a low temperature, low humidity environment.

Abstract: In a charging device used in a cleanerless image forming apparatus and including a charging brush in contact with an image bearing member, a scraping member is provided which is in contact with the charging brush with a predetermined amount of indentation overlap on an upstream side of a contact portion between the charging brush and the image bearing member with respect to a rotational direction of the charging brush. With such an arrangement, the developer, which is scraped from the charging brush by the scraping member and then adheres onto the image bearing member, is recharged by the charging brush so as to be collected by a developing-cleaning device.

Abstract: The door (3) of a laser printer (1) is pivoted to the frame (1c) of the printer by a pin (21) of hinge (19). When the door is shut, link (33) is rotatably connected to the hinge at a location above the pin. Link 33 has an elongated slot (33a) at its end opposite the hinge in which a pin (51) does not encounter the edge of the slot when the door is closed. Spring (31) therefore rotates U shaped link 11 around its pivot point (15) to the frame to bring charge roller (9) into contact with photoconductor drum (5). When the door is manually opened, spring 31 provides an upward force, link 33 is moved forward where the slot engages pin 51, which pivots both link 13 and door 3 upward. Force of the charge roller against the drum is by the spring as the only active element, thereby providing a controlled force.

Abstract: A charging apparatus and method used in an image forming apparatus uses a charging apparatus to apply a charging potential to a photosensitive body, a voltage measuring device that measures the charging potential and outputs a measured charging potential signal, an environmental condition sensor which senses at least one environmental condition and outputs an environmental condition signal, and adjustable voltage application which applies an applied voltage to said charging member, and a controller, where the controller controls an amount of the applied voltage applied to the charging member in accordance with the charging potential signal and the environmental signal, where the applied voltage is adjusted to compensate for the sensed environmental condition.

Abstract: A cleaning device of an electrophotographic processor having a conductive cleaning blade for performing both charging and cleaning operations. The cleaning device of an electrophotographic processor includes a conductive cleaning blade installed at the cleaning device for removing residual toner remaining on an outer surface of a photosensitive drum, and a high pressure unit electrically connected to the conductive cleaning blade for applying voltage to the conductive cleaning blade to charge the surface of the photosensitive drum during charging operation and to subsequently clean the surface of the photosensitive drum from residue toner during cleaning operation.

Abstract: An image formation is conducted in such a manner that an image exposure is applied to a photosensitive member having a surface charged by the charger to form an electrostatic latent image, which is developed by a developing device into a visible image, and the visible image is transferred to a recording material. In this image formation, the above developing device is constructed to include a developer carrying member to which a developing bias voltage is applied. The developer carrying member has a surface, which carries one-component developer and is adapted to move while contacting the photosensitive member, and is operable to remove residual developer on the photosensitive member after the transferring.

Abstract: The present invention provides a charge apparatus comprising a charge member to which voltage is applied for charging a member to be charged, the charge member having a bearing member for bearing a magnetic particle layer contacted with the member to be charged. The bearing member includes therein a plurality of magnetic poles disposed in a circumferential direction thereof, and the magnetic poles are arranged in a spiral fashion.

Abstract: An image forming apparatus includes an image bearing device, a charger contactable to the image bearing device for effecting contact charging of the image bearing device, the charger being supplied with a voltage having a DC component and an AC component, and the charger being provided with an electrode for receiving the voltage; wherein the following is satisfied: when an electric field formed between the image bearing device and the electrode is not more than .vertline.E/d.sub.SD .vertline. (V/m), a resistance of the charger per unit area of contact between the image bearing device and the charger is larger than20E/(wCV.sub.DC) (.OMEGA.m.sup.2)and is larger than the resistance when the electric field is more than .vertline.(E+V.sub.DC)/d.sub.SD .vertline. (V/m)where E(V) is an amplitude of the AC component; w(rad) is an angular velocity of the AC component; d.sub.SD (m) is a minimum distance between the electrode and the image bearing device; C(F/m.sup.

Abstract: A charging apparatus or an electrophotographic apparatus includes an electrophotographic photosensitive member including a photosensitive layer provided on a conductive supporting member, and a charging member including magnetic particles, disposed to be in contact with the electrophotographic photosensitive member, for charging the electrophotographic photosensitive member when a voltage is applied to the charging member. The layer of the electrophotographic photosensitive member most separated from the conductive supporting member has a volume resistivity between 10.sup.8 .OMEGA..cm and 10.sup.15 .OMEGA..cm, and the magnetic particles have a hygroscopic property such that the ratio H/L of the maximum value H to the minimum value L of the amount of water contained within the particles is at least 1 and less than 4.

Abstract: An image forming apparatus includes an image bearing member; a charging member contactable the image bearing member to charge the image bearing member at a charging position; wherein an AC current applied to the charging member is constant-current-controlled when a region of the image bearing member which is going to be an image formation region is at the charging position, and wherein a current flowing through the charging member is detected when a region of the image bearing member which is going to be a non-image-formation region is at the charging position, and the AC current is determined on the basis of the detected current.

Abstract: An image forming apparatus includes an image bearing member; an image forming device for forming an image on the image bearing member, the image forming device being provided with a charging member which is disposed in contact or proximity with the image bearing member to electrically charge the image bearing member; wherein the charging member is supplied with an oscillating voltage, and there is provided a voltage set period in which a peak-to-peak voltage of the oscillating voltage is higher in a period in which the image is not formed on the image bearing member than in a period in which the image is formed on the image bearing member.

Abstract: An imaging member comprised of a supporting substrate with a coating thereover and wherein the coating is comprised of resin, electrically conductive metal oxide particles, and insulative metal oxide particles, wherein each electrically conductive particle is substantially electrically isolated and separated from any other of the electrically conductive particles by the insulative particles.

Abstract: Imaging forming apparatus includes an image bearing member, an image formation unit for forming an image on the image bearing member, and a detection unit for detecting a voltage-current characteristic between the image bearing member and the charging member. The image formation unit has a charging member contactable to the image bearing member to charge the image bearing member. An image formation condition for the image bearing member is determined on the basis of a plurality of detection operations of the detection unit.

Abstract: An image forming apparatus adopting a cleaningless process using contact-type charging means, includes developer scattering means which is located between the charging means and an exposure position in contact with the surface of an image carrier. For example, the developer scattering means is a conducting brush which scatters, catches and temporarily holds the residual toner on the image carrier. With this structure, even in an image forming apparatus adopting the cleaningless process using the contact-type charging means, the residual toner on the image carrier is scattered and caught by developer catching means before the residual toner reaches the exposure position. Thus, a lowering of the image quality which is caused if the residual toner is patterned by the charging means is prevented, thereby improving the image quality.

Abstract: A device for driving a charge roller, charge belt, image transfer roller, image transfer belt or similar contact type charging member used to charge an image carrier of an image forming apparatus in contact with the image carrier. The charging member is driven by an exclusive motor independent of a motor for driving the image carrier. A drive gear and a driven gear are formed of metal and resin, respectively. A flywheel is mounted on a drive roller for causing the charging member to rotate. The drive side has greater rotation energy than the driven roller side. A flywheel is also mounted on the drive gear.

Abstract: A contact charging system uniformly charges a photoconductive surface by the use of a resistive belt surrounding and moved by two rollers and in contact with the photoconductive surface. The roller at the pre-nip area is grounded while that at the post-nip area is kept at a desired high potential. Alternatively, a pair of shoes are used for contact charging a photoconductive surface with one of the shoes being grounded and the other being biased to a desired DC potential by a biasing source. A resistive film is in contact with the pair of shoes with both the film and shoes being in contact with the photoconductive surface. Also, a blade is used to uniformly charge a photoconductive surface with one portion of the blade being grounded and another portion being biased to a desired DC potential. The blade is in direct contact with the photoconductive surface. This charging system tailors the electric field so that air breakdown only occurs at the post-nip area.

Abstract: An image forming apparatus includes a charging rotary brush in contact with a photosensitive member, a laser beam irradiator to form an electrostatic latent image, a developing unit for developing the latent image into a visible image and collecting residual developer remaining on the surface of the photosensitive member after the visual image is transferred to a transfer material, and a power source unit for applying to the charging rotary brush an oscillating voltage fulfilling the requirement of:.DELTA.t<L/Vpc or .DELTA.t>3.times.L/Vpcwherein .DELTA.t is the time taken for the oscillating voltage to vary between .+-.300 V above and below the central oscillating voltage value between the peaks of the voltage, L is the printing pitch, and Vpc is the speed of movement of the surface of the photosensitive member.

Abstract: The present invention comprises a photosensitive member supported for rotation within a unit case and a charger for uniformly charging the photosensitive member. The charger includes a conductive member in the form of a sheet held in contact with the photosensitive member and a supporting member having a non-flat cross section for supporting the conductive member, in which the charger applies a voltage formed of a direct-current voltage with an alternating-current voltage added thereto to the conductive member to thereby uniformly charge the photosensitive member. The charger is kept in place by having the supporting member fixed to vertical planes of the unit case at positions off vertical planes crossing the photosensitive member.

Abstract: A charging member for electrophotography comprising a surface layer, wherein the surface layer comprises a resin and an alkali metal salt contained therein.

Abstract: 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.

Abstract: A charging member for charging a member to be charged, includes a magnet member and a surface electroconductive layer for supporting electroconductive magnetic particles, the layer being supported by the magnet member and rotating together with the magnet member in a region supporting the magnetic particles.

Abstract: The image forming method comprises, electrostatically charging an image bearing member using a contact charging assembly, forming an electrostatic latent image on the image bearing member thus charged, developing the electrostatic latent image with a magnetic toner to form a toner image and transferring the toner image to a transfer medium, wherein the charging assembly comprises a magnetic brush formed from conductive magnetic particles magnetically bound, and the charging assembly comes into contact with the image bearing member to charge the surface of the image bearing member by directly injecting charges into the electron level present on the surface of the image bearing member and the magnetic toner has a value of .sigma..D..delta. of 150 or less, where the value is obtained by multiplying i) a magnetization quantity .sigma. (Am.sup.2 /kg) in a magnetic field of 1K oersted as measured by a vibration magnetometer, ii) a weight average particle diameter (D.sub.4) D (.mu.

Abstract: A charging device includes a substantially cylindrical charging electrode formed by rolling a flexible, semiconductive film, an electrode support member inserted in the substantially cylindrical charging electrode to support the charging electrode so as to be in contact with the turning surface of a charge acceptor, and a voltage applying means for applying a charging voltage to the charging electrode. The electrode support member is held with a gap between the electrode support member and the charge acceptor so that the charging electrode can be turned by an electrostatic force acting between the charging electrode and the charge acceptor. When a charging voltage is applied to the charging electrode, the charging electrode is pulled toward the charge acceptor by an electrostatic force acting between the charging electrode and the charge acceptor.

Abstract: A charging device for charging a moving photoconductor. The charging device includes a charging member, an electric power supply for applying a voltage to the charging member, and a light exposing device, such as a LED for exposing surfaces of the charging member and the photoconductor in a closing region where the surfaces of the charging member and the photoconductor move closer to each other. The charging member is a blade having a transparent layer for guiding a light beam from the LED to the closing region and a shading layer for shading the light beam to a contacting region and a separating region. The contacting region is where the surfaces of the charging member and the photoconductor contact, and the separating region is where the surfaces of the charging member and the photoconductor gradually separate from each other.

Abstract: An image forming apparatus includes an image bearing member for bearing an image; a charging member contactable to the image bearing member to electrically charge the image bearing member, wherein a toner image is formed on the image bearing member using electric charge provided by the charging member; a transfer device for transferring the toner image from the image bearing member onto a transfer material; a controller for switching a potential applied to the charging member to form a blank area at a predetermined position of the transfer material; wherein the following is satisfied for formation of the blank area;X.ltoreq.t x VPS.ltoreq.10where VPS (mm/sec) is a moving speed of the image bearing member, t (sec) is a switching period of the controller, and X (mm) is a distance from a charge starting position to a charge ending position in a direction of movement of the image bearing member.

Abstract: An image forming apparatus includes image bearing member or members for bearing an image; charging member for sequentially charging a surface of the image bearing member or members to form an image thereon; a voltage source for applying an oscillating voltage to the charging member, the oscillating voltage including a first frequency and a second frequency which is different from the first frequency during charging by the charging member.

Abstract: In an electrophotographic system, an electrostatic latent image as formed on a photoreceptor is developed with a developing agent to form a toner image thereon, a transfer paper is laid over the toner image and pressure is applied to the photoreceptor and the transfer paper so as to transfer or simultaneously transfer and fix the toner image onto the transfer paper. The photoreceptor is one having a surface protecting layer and a light-sensitive layer made of a hydrogenated and/or fluorinated amorphous silicon. The light-sensitive layer and the surface protecting layer of the photoreceptor are uniformly heated to a constant temperature. A charging device or a discharging brush or blade is used as a device of discharging the charges of the photoreceptor after the transference.

Abstract: A contact charging device which charges the surface of an electrostatic latent image carrying member rotating at a high speed by contacting a charging member to the surface of the image carrying member. The charging member has a conductive substrate, a conductive elastic layer superimposed over the conductive substrate and having a JIS-A hardness of 30.degree. or greater, and a conductive resin layer superimposed over the conductive elastic layer and having a 10% elongation load of not more than 700 gf on a 1 cm wide section.