Abstract: A developing apparatus includes a container for containing a developer including magnetic particles. A rotatable developer carrying member is disposed in the container and faced to an image bearing member, for carrying the developer to a developing zone. A magnet is provided in the developer carrying member, and a magnetic sealing member is disposed adjacent to and in a rotational direction of the developer carrying member in a region inside of the container adjacent a longitudinal end of the developer carrying member, wherein the magnetic sealing member cooperates with the magnet to form a magnetic field effective to form a magnetic brush of the developer between the magnetic sealing member and the developer carrying member, and wherein an outer end, with respect to the longitudinal direction of the developer carrying member, of the magnetic sealing member is disposed in a range between 2 mm outwardly away from an end of the magnet and 1 mm inwardly away therefrom.

Abstract: An electrophotographic printer 10 having a control system 51 for controlling a stepper motor 50. The control system 51 includes a motor speed drive circuit 52, a microprocessor 54, and a clock 58. The motor speed drive circuit 52 has a programmable driver 56 and a logic circuit 60. The microprocessor 54 outputs a speed change value each time a change in the stepper motor is desired. The programmable driver 56 stores the speed change value and incrementally counts down from the speed change value to zero in synchronization with a clock pulse from the clock 58. Upon reaching zero, the programmable divider 56 outputs a speed command signal to the logic circuit 60, which in turn outputs drive signal to control the operation of the stepper motor 50. The microprocessor 54 only outputs a new speed change value when a change in stepper motor operation is desired. If no change is desired, the programmable divider 56 uses the last input speed value to control the stepper motor.

Abstract: A sheet guiding apparatus and an image forming apparatus incorporating same. The copy sheet being transported to the transfer station by a pair of feed rollers is guided by a pair of guide panels arranged in one direction and an opposite direction. These guide panels are located in an extension state with a substantial intervening spacing at the moment transport starts, and are located in a contracted state with a narrow intervening spacing at the completion of sheet transport so as to prevent transport error and transfer dislocation. The timing by which the guide panels change form the extension state to the contraction state changing in accordance with the copy sheet size to assure guidability regardless of the size of the copy sheet.

Abstract: A process cartridge removably mounted with respect to the body of an image forming apparatus, which includes an image bearing member, a charging device for uniformly charging the surface of said image bearing member, with the charging device including a discharge electrode and a control electrode, a device for regulating the potential of the control electrode to a predetermined value, and an operation change-over device for rendering the regulating device operative or inoperative.

Abstract: An electrostatic recorder including an electrostatic latent image measuring instrument for measuring a state of an electrostatic latent image formed on a photosensitive substance, and executed a printing process until an electrostatic latent image formed on a surface of a photosensitive substance based on measured data is transferred onto a blank form as a visual image by a transfer device by adjusting control factors such as exposure, exposure time, electrostatic charge voltage, development bias, temperature and humidity. The electrostatic latent image measuring instrument is provided with distance sensors which, when a measuring electrode is disposed near to the photosensitive substance, maintains a constant distance therebetween. It is thus possible to measure an electrostatic latent image even if the photosensitive substance is eccentric.

Abstract: In an image forming apparatus according to the present invention, a plurality of image forming process units are aligned to face a horizontal transportation section of a paper transportation path. A transfer belt unit is provided to successfully transfer images formed on photoreceptor drums of the process units to a transfer medium. A flashlight device is interposed between each two adjacent process units. Developing agent images formed by means of the process units and transferred to the transfer medium are fixed to the medium by means of the flashlight devices. By doing this, a developing agent transferred to the transfer medium by means of a preceding process unit is fixed to the medium by means of its corresponding flashlight device. Thus, in an image forming process using a subsequent process unit, images can be securely superposed without causing the previously transferred developing agent to separate from the transfer medium.

Abstract: A developing device includes a device body which has a toner reception port and supplies toner stored therein to a photosensitive member, a toner cartridge, which is detachably mounted in the device body in coincidence with the toner reception port, has a toner discharge port opposed to the toner reception port, and supplies toner stored therein to the device body through the ports, a sealing member which is mounted on the device body to surround the toner reception port and seals between the device body and the toner cartridge mounted in the device body, and a pressing mechanism which is provided on the toner cartridge and presses the toner cartridge on the sealing member when the toner cartridge is mounted in the device body.

Abstract: A developing apparatus for developing an electrostatic latent image includes a movable developer carrying member for carrying a one component developer to a developing zone in which the developer is supplied to an electrostatic latent image bearing member; and a regulating member for regulating a thickness of a layer of the developer to be carried to the developing zone on the developer carrying member; wherein the developer carrying member comprises a coating layer comprising a resin material in which fine graphite particles are dispersed, and wherein an inclination of a work function measurement curve of a surface of the coating layer is not less than 10 (cps/eV).

Abstract: An image forming apparatus according to the present invention includes a photoreceptor, an image forming unit for forming a toner image on the photoreceptor, an intermediate transfer medium to which the toner image formed on the photoreceptor is transferred at a transfer position and from which the transferred toner image is transferred to a sheet, a cleaning unit for removing toner on the intermediate transfer medium, and a controller for providing control for the sequence of activating a preliminary cleaning of the transfer belt for a predetermined time period, starting image formation after the preliminary cleaning is terminated, actuating a subsequent cleaning after termination of the transfer process, and then starting image formation in response to an image formation start signal output during the subsequent cleaning.

Abstract: An image forming apparatus includes an image bearing member; a system for forming a latent image on the image bearing member; a developing device for developing the latent image formed on the image bearing member, the developing device including plural developing units, and each of the developing units including a developer carrying member movable to carry thereon the developer to supply the developer to the image bearing member and a developer scatter preventing member at a position adjacent the developer carrying member; a driver for moving a selected one of the developing units to a predetermined position faced to the image carrying member; a device for positioning the selected developing unit to an operating position for a developing operation; a member which is contacted to or close to the scatter preventing member when the selected developing unit is placed at the operating position.

Abstract: There is disclosed a system and method for assembling all of the parts of a xerographic system in a unitary housing. The unitary molded housing contains the xerographic optics, the modulator, the toner and developer cartridges as well as the printr drum. Using this unitary housing, the modulator can be aligned by using optical sensors in substitution for the printing drum during assembly.

Abstract: A rotary developing device for color image forming equipment has a plurality of developing units around a common rotary shaft and rotates the developing units about the common shaft to bring any one of them to a developing position. A drive connecting and disconnecting device in the form of a clutch is provided integrally with each developing unit and sets up and interrupts drive transmission from a drive source to only one of the developing units.

Abstract: An image forming apparatus for forming a toner image on a recording material applies a bias voltage having the same polarity as the toner to a core bar of a fixing roller. A fixing entrance guide is provided so that the recording material approaches or contacts the fixing roller when the recording material enters a contact-pressure region formed by the fixing roller and a pressing roller. Thus, offset of toner to the fixing roller is prevented.

Abstract: Disclosed is a fixing device where a copying medium carrying a non-fixed toner image thereon is passed between a pair of fixing rolls as being kept in direct contact with each other under pressure so as to fix the non-fixed toner image on the copying medium, the device being characterized in that a toner release at least containing, as an active ingredient, a functional group-containing organopolysiloxane of a general formula (I): ##STR1## the organopolysiloxane having a viscosity of from 10 to 100,000 cs at 25.degree. C., is supplied to at least the fixing roll of being brought into contact with the non-fixed toner image of the said pair of fixing rolls. Using the toner release, the copying medium releasability from the fixing roll to which the toner release is applied is good and the heat-resistance of the fixing roll is also good.

Abstract: The need for adjustment of the transfer and fusing subsystems of an electrostatographic machine is determined by adjusting the machine's process control parameters until density reading of an untransferred toner image of a test patch are within specification, or are otherwise acceptable. The toner image is transferred and fused to an image receiver sheet, and deficiencies in the images on the receiver sheet indicate the need for adjustment of the transfer and/or fusing subsystems.

Abstract: A dual augar development apparatus for use in an electrostatographic reproduction machine such as copier or printer, includes a pair of identical single piece auger devices mounted therein and each having a shaft and a plurality of integrally formed blade members so as to require no blade-member-to-shaft-assembly. A last blade member includes a cross-transfer member connected thereto and integrally formed therewith. The blade members are semi-elliptical and form a single straight row of such members on the shaft. The row is aligned circumferentially so as to result in intermittent augering of developer material in the development apparatus.

Abstract: An apparatus for storing marking particles is described which includes a container defining a chamber for storing the marking particles therein and having an opening defined therein for the discharge of the marking particles therefrom. The apparatus further includes a seal member secured to the container, the seal member having an opening defined therein which is at least partially coextensive with the opening of the container for the passage of marking particles therethrough. Moreover, the apparatus includes a cover positionable over the opening defined in the seal member, the cover being removably secured to the seal member with an adhesive material.

Abstract: An image forming apparatus for forming a toner image on a recording medium. The apparatus includes a photosensitive drum on which a latent image is formed, a developing/cleaning device for developing the latent image with a developing agent and for removing the developing agent remaining on the photosensitive drum therefrom while the latent image is developed, and a transfer device for transferring the developed image on the photosensitive drum to the sheet. The apparatus further includes a disordering device for disordering the developing agent remaining on the photosensitive drum, after transfer of the developed image by the transferring means, to render the developed image nonpatterned. The disordering device includes a contact member having projections and depressions formed with a prescribed inclined angle relative to the direction intersecting at right angles the rotating direction of the photosensitive drum at the contact portion with the photosensitive drum.

Abstract: A developer material mixing blender includes a shaft and self-locking segments. Each segment has a hollow hub, an inner ribbon for moving material towards one end, an outer ribbon for moving material in a second stream towards another and opposite end, and an interstream cross-mixing rib for moving material laterally from one to the other of the first and second streams in order to insure good mixing.

Abstract: An electrophotographic image forming apparatus for forming a color toner image by a developing device and fixing the toner image by a fixing device including top and bottom rollers. When OHP mode for forming images on transparency sheets is selected, the time required for fixing the toner image is prolonged so as to assure the transparency of the image fixed to a recording member. That is, if the size of the transparency sheet is larger than a predetermined value, the transparency sheet is sent to a returning path which returns the recording member discharged from the fixing device to the fixing device again, and if the size of the transparency sheet is smaller than the predetermined value, the fixing device is operated more slowly than a case of forming images on non-transparency sheets. Further, when the OHP mode is selected, heating power is supplied to both top and bottom fixing rollers, and when the OHP mode is not selected, the heating power is supplied to the top fixing roller only.