Abstract: An image forming apparatus includes a plurality of image forming stations forming images of different colors on a transfer material and is provided along a direction of conveyance of the transfer material by a conveying system, in which a toner replenishing system is operated on the basis of a result of a detected magnetic permeability a detecting device and the developer, which is not transferred to the transfer material but and, which remains on an image bearing member is collected by a developing system.

Abstract: A developing device comprises a developer bearing member for bearing and conveying a developer having a toner and a carrier, a first magnetic pole arranged in the developer bearing member, a second magnetic pole arranged in the developer bearing member, a polarity of the second magnetic pole being opposite to a polarity of the first magnetic pole, and the second magnetic pole being adjacent to the first magnetic pole and arranged on a downstream side of the first magnetic pole in a moving direction of the developer bearing member, a regulating member for regulating a layer thickness of the developer borne by the developer bearer, the regulating member being arranged in the vicinity of the second magnetic pole and a concentration detector for detecting a concentration of the toner in the developer.

Abstract: An image forming apparatus uses a toner wherein when a weight average diameter of the initial toner in a developing device is set to D1, and a weight average diameter of a toner forming an initial toner image on an image bearing member is D2, such that D1≧D2 is satisfied.

Abstract: An image forming method includes (i) a charging step of using a charging device including conductive magnetic particles, a rotatable conductive-magnetic-particle carrying member for carrying and conveying the conductive magnetic particles, and a plurality of magnetic-field generation means provided within the conductive-magnetic-particle carrying member, and charging a surface of an image bearing member by applying a voltage to the conductive-magnetic-particle carrying member and causing the conductive magnetic particles to contact the image bearing member, (ii) a latent-image forming step of forming an electrostatic latent image on the charged surface of the image bearing member, and (iii) a developing step of using a developing device facing the image bearing member and including a two-component developer including a toner and magnetic carrier particles, a developer carrying member for carrying the two-component developer, and a plurality of magnetic-field generation means provided within the developer carr

Abstract: An image forming apparatus includes an image bearing member for carrying an electrostatic image, a contact charger for electrically charging the image bearing member while contacting to a surface of the image bearing member, the contact charger forming an oscillating electric field having a frequency of 100-600 Hz; a developer for developing the electrostatic image on the image bearing member with a developer comprising toner and a carrier having a volume resistivity value of 106-1010 &OHgr;.

Abstract: An image forming apparatus comprises a charging member, an image bearing member and a developer bearing member. The charging member comprises a first magnetic field generating device, wherein a first magnetic field with a first magnetic pole closest to the image bearing member has a half-value width &agr;°. Measuring from a center of the charging member, an angle between a closest point of the image bearing member and a maximum magnetic flux density of the first magnetic pole is &thgr;c°. The developer bearing member comprises a second magnetic field generating device, wherein a second magnetic field with a second magnetic pole closest to the image bearing member has a half-value width &bgr;°. Measuring from a center of the developer bearing member, an angle between a closest point of the image bearing member and a maximum magnetic flux density of the second magnetic pole is &thgr;d°.

Abstract: A developing device having a developer bearing member for carrying thereon a developer having toner and carrier and conveying the developer to a developing area, an agitating member for agitating the developer, a rotation radius R (m) of the agitating member being 5.0.times.10.sup.-3 (m)<R<8.0.times.10.sup.-3 (m), and a density sensor for detecting a density of the toner in the developer, the density sensor detecting any change in the density of the toner as a change in a magnetic permeability of the developer, wherein when a shortest distance between an outermost surface of the agitating member and a detecting surface of the sensor is defined as Dmin (m) and a half length of the detecting surface of the sensor in a plane perpendicular to a rotary axis of the agitating member is defined as r, 0 (m)<Dmin<1.0.times.10.sup.31 3 (m) and 0.4<r/R<0.75.

Abstract: A developing apparatus has a developer bearing member disposed in opposed relationship with an image bearing member bearing an electrostatic image thereon with a gap of 6.times.10.sup.-4 m or less with respect to the image bearing member, and bearing and conveying a developer thereon. The developer bearing member is moved in a direction opposite to the direction of movement of the image bearing member in the portion opposed to the image bearing member, and the developer has a non-magnetic toner and a carrier of which the magnetization rate in a magnetic field of 1000 gauss is equal to or greater than 30 emu/cm.sup.3 and equal to or less than 200 emu/cm.sup.3 and the specific resistance at electric field intensity of 5.times.10.sup.4 V/m is 10.sup.12 .OMEGA.cm or greater. The developing apparatus further has applying means for applying a bias voltage having a vibration component to the developer bearing member.

Abstract: An image forming apparatus having an image bearing member for bearing an electrostatic image to be developed by toner, a transfer device for transferring a toner image formed on the image bearing member onto a transfer material, and developing and cleaning device for developing the electrostatic image with developer including toner and carrier and for cleaning residual toner remaining on the image bearing member after transferring, the developing and cleaning device having a developer bearing member for bearing the developer and serving to effect development and cleaning by causing a magnet brush formed by the carrier to contact with the image bearing member, and wherein the following relation is satisfied:.vertline.V.sub.s1 V.sub.dr .vertline./.vertline.V.sub.dr .vertline..times.L.times.m.times..alpha..gtoreq.7(where, V.sub.s1 is a moving speed (mm/sec.) of a surface of the developer bearing member, V.sub.dr is a moving speed (mm/sec.

Abstract: A developing method includes forming a magnetic field between an image bearing member bearing an electrostatic image and a developer carrying member carrying a developer comprising toner particles and carrier particles; and contacting chains of carrier particles formed on the developer carrying member to the image bearing member; wherein an absolute value of an intensity of a magnetic field in a movement direction of the developer carrying member over the entire portion of the developer carrying member at a position where the carrier is contacted to the image bearing member is positive.

Abstract: A developing method for developing an electrostatic image on an image bearing member with a two-component developer includes the steps of bearing a developer containing toner particles and carrier particles on a developer bearing member to a contact region formed between the developer bearing member and an image bearing member bearing an electrostatic image thereon, and rubbing the image bearing member with the magnetic brush with a contact pressure equal to 0.7 gf/cm.sup.2 or less.

Abstract: An image forming apparatus includes an image bearing member; a latent image forming device for forming on the image bearing member a dot distribution electrostatic latent image in accordance with image signals corresponding to an object image; a developing device for developing the latent image formed on the image bearing member by the latent image forming device, in a developing station and by a developer containing toner and magnetic carrier; wherein the developing device includes a developer carrying member for carrying and conveying the developer to the developing station, and a magnetic field generating device provided within the developer carrying member, for forming a magnetic brush of the developer and contacting the magnetic brush to the image bearing member; and wherein a degree .sigma.d (emu/cm.sup.

Abstract: An arrangement and structure for an oil pan system to permit mounting a vertical in-line engine in a vehicle in a horizontal or nearly horizontal attitude includes a cylinder block of the engine having an opening on the side wall thereof, a cover attached to the cylinder block where an ordinary oil pan is usually mounted, an adapter plate fastened to the lower side wall of the cylinder block and bottom of the cover, and an oil pan attached to the lower surface of the adapter plate. The adapter plate allows the oil pan to extend and always remain below the cylinder block, so that the return paths from the lubricated portions of the engine to the oil pan are shortened.

Abstract: An exhaust gas recirculation apparatus of the so-called exhaust gas pressure control type, including, in combination, a vacuum-operated pressure control valve adapted for controlling the pressure of the exhaust gas in the exhaust gas recirculation passageway connecting the exhaust manifold to the intake manifold, and a vacuum control valve adapted for controlling the level of the vacuum signal transmitted to the pressure control valve, for obtaining a predetermined constant pressure in the exhaust gas directed to the pressure control valve. A flow control valve is provided for controlling the amount of exhaust gas directed to the pressure control valve in accordance with the load of the engine. The flow control valve has an exhaust gas passageway with a constant flow area, and another exhaust gas passageway with a flow area that is varied in accordance with the load of the engine.

Abstract: A timing chain tensioner comprising a housing adapted to be mounted on an engine block and formed with cylinder bore and connecting passage for the escape of air from the cylinder bore to the atmosphere, a plunger slidably fitted in the cylinder, and a closure member for closing the passage. When the plunger is to be placed into the cylinder for the assembling of the tensioner the passage is kept open to facilitate the plunger insertion, and after the insertion the passage is closed by the closure member.