Abstract: A transfer device for use in an electrophotographic copying machine includes a charger and is disposed opposite to a surface of a photosensitive body where a toner image is formed. When a copy paper is passed through the gap between the transfer device and the photosensitive body surface, the charger discharges and at the same time screening plates are moved into screening positions in the gap to shield the edge sections of the copy paper. Talc particles falling off from these edge sections of the passing copy paper can be thereby prevented from becoming attached to the surface of the photosensitive body.

Abstract: An image forming apparatus including a main body and a processing unit detachably mounted in the main body. The processing unit includes at least one of an image bearing member and developing device. The number of image forming repetitions of the processing unit are counted by a counter in the main body. When the counted number for the processing unit reaches a reference value representing the effective life of the processing unit, an alarm device actuates to notify the user that the effective life of the processing unit has been reached.

Abstract: The present invention relates to an electrophotographic copying machine which is capable of producing positive copies from both positive and negative originals. According to the invention, two units of developing apparatuses, each containing a toner with a polarity opposite to each other, are selectively mounted in position on the main body of the copying machine according to whether the copying is from positive to positive or from negative to positive so as to apply to the transfer charger a voltage with a polarity opposite to that of the toner.

Abstract: This invention is a transfer means in a electrographic printing apparatus having a charge retaining member with a relatively high background potential of a first polarity, a transfer corotron having a relatively high potential of a second polarity and providing a transfer region for a transfer of toner to copy sheets, and a pretransfer baffle disposed adjacent to the transfer corotron, the pretransfer baffle being charged to a potential approximately the same as the charged retaining member and having said first polarity, the pretransfer baffle and the charge retaining member forming a gap for the passage of copy sheets to the transfer region, and the copy sheet being in contact with the charge retaining member before reaching the transfer region.

Abstract: An image forming apparatus including a developing unit for developing an electrostatic latent image formed on an image carrier, and an image forming unit. A mechanism is provided which permits the image forming unit and developing unit to be mounted on or dismounted from the image forming apparatus in the proper order. A developing unit-positioning guide 15 provided by first mounting the image forming unit on the image forming apparatus.

Abstract: An improved electrophotographic copier is proposed which includes a first static charger; an image exposure unit; a second charger provided with a grid; and a developer having a developing electrode, all being arranged around a photosensitive rotatable drum.The second charger is impressed selectively with an a.c. voltage or a d.c. voltage which has an opposite polarity to that applied to the first charger. The voltage impressed to the grid has same polarity with that which is applied to the first charger. The developing agent contained in the developer includes such statically charged toner as having an opposite polarity to that of static latent images formed on the drum surface. The copier operates selectively in standard copy mode or in marginal image outline formation mode. The developing service is nevertheless carried out in the normal manner, thus employing no reverse development mode.

Abstract: A sheet storing apparatus capable of discharging sheets supplied by an image forming apparatus either face-up or face-down.

Abstract: A system for displaying graphic or pictorial intelligence, including half tones and the like. The system includes an endless belt having an electrically insulating externally facing surface; an electrostatic charge writing head for depositing an electrostatic charge pattern on said belt in correspondence to a desired image to be formed thereupon; a developing station for depositing toner upon said electrostatic image to render same visible; means to move said belt past said imaging and development stations and to a viewing position whereat said display may be seen by a user; and a casing enclosing said belt, writing head, and developing station, one side of the casing being provided with a transparent wall to enable the developed image to be perceived by the user.

Abstract: A copying machine is disclosed which has a plurality of copying paper feeding means, means for detecting a document size to be copied, means for designating a copying magnification and means for designating one paper feeding means to be used preferentially.Further, the copying machine has calculation means for calculating the most suitable size based on the document size and the designated magnification.One paper feeding means is automatically selected referring to data corresponding about the document size, the most suitable paper size and the preferential paper feeding means and so on.

Abstract: A lamp system which erases selected portions of an electrically charged photoconductive member. The lamp has a transparent housing defining a chamber filled with a gaseous medium. A charge is induced across a selected region of the gaseous medium. This causes the gaseous medium to ionize in the selected region so as to emit light rays thereat. The light rays illuminate the electrically charged photoconductive member in the selected region to discharge the charge thereat.

Abstract: The specification discloses apparatus by which multiple reproductions can be produced from an original, all reproductions from the same original being of substantially identical quality. An electrographic machine substantially uniformly charges an electrographic recording member to a predetermined initial voltage and imagewise exposes the charged recording member at a nominal exposure level to produce a latent charge image. The initial voltage level and the exposure level are process control parameters of the machine, which also includes a biased electrode for controlling deposition of toner to the latent charge image. Signals are produced and stored having values characteristic of (1) the level of at least one of the parameters and (2) the bias voltage level which are associated with a desired reproduction quality of an original.

Abstract: A variable magnification copying machine for guiding light reflected from an original onto a photosensitive body through means of a plurality of mirrors and a lens system and for forming a latent image of the original upon the photosensitive body includes a variable magnification optical apparatus. The variable magnification optical apparatus selects one of at least two variable magnification modes based upon U variable and U fixed systems in each one of at least two regions obtained by dividing a variable magnification range and varies the magnification by a combination of the variable magnification modes. The variable magnification mode based upon the U variable system changes the optical path length from a surface of the original to the photosensitive body so as to vary the magnification while maintaining the focal length of the lens system constant.

Abstract: A copying machine, including a photosensitive drum; a corona charger; an exposure device for exposing the photosensitive drum to an optical image of an original; a developing unit for developing a toner image on the photosensitive drum; a transfer corona charger for transferring the developed toner image to copy paper; a device for mechanically separating the imaged copy paper from the photosensitive drum; and a system for cleaning the drum after the image transfer, which includes an eraser lamp disposed adjacent the copy paper delivery side of the transfer corona charger at a position for illuminating copy paper from the rear side thereof upon image transfer thereto, and a control unit for controlling the operation of the transfer corona charger and the eraser lamp, thereby assuring smooth separation of copy paper after image transfer and efficient transport of the paper.

Abstract: The invention is an electrophotographic imaging process comprising forming a first electrostatic latent image on an imaging surface of an electrophotographic imaging member comprising an electrophotographic insulating layer and an electrically conductive layer, developing said first electrostatic latent image with a conductive two-component developer having a conductivity between about 10.sup.-10 ohms-cm.sup.-1 and about 10.sup.-14 ohms-cm.sup.

Abstract: The present invention is a membrane switch having first and second contacts, a graphic overlay, and a bezel combination, the graphic overlay molded to the bezel, the graphic overlay supporting a tactile actuator, the actuator being molded to the overlay and disposed in relation to the contacts for engagement of the contacts upon application of pressure to said actuator. A plasma, solid area illuminator behind an LCD display is also provided as well as a scrolling device to layer information presented to an operator.

Abstract: In electrographic apparatus a latent image on a flexible photoconductor is developed with toner particles at a development station and subsequently transferred to a receiver sheet, such as a copy sheet, and then fused to the sheet. Sometimes unwanted particles also are on the photoconductor, including the area of a developed image on the photoconductor. Unless the unwanted particles are removed before the developed image is transferred to a copy sheet, the particles can create image voids or other defects in the image on the copy sheet. These particles are removed by a vacuum system including a plenum having an inlet opening located closely adjacent the surface of the photoconductor between the development station and the transfer station. It is important to precisely maintain the desired spacing between the vacuum plenum opening and the photoconductor.

Abstract: An image forming apparatus includes a rotatable photosensitive member and is adpated to form an image on a paper by steps of charging the photosensitive member with a main charger, exposing to form an electrostatic latent image, developing the latent image with a toner, transferring the toner image to a paper with transferring charger. Furthermore the apparatus includes a sensor to detect the amount of the toner adhering to the photosensitive member or to the paper so as to detect a malfunction in the main charger or in the transferring charger.

Abstract: A surface of a heated fixing roller is coated with a tetrafluoroethylene resin in which pin holes are present in the range of about 5-30 unit/cm.sup.2 and the diameter of the pin holes is in the range of about 5-20 .mu.m.

Abstract: An apparatus for detecting image density in an image forming machine includes a first sensor for receiving mainly a regular reflecting light reflected from a reference toner image, and a second sensor for receiving mainly scattered reflecting light reflected from the reference toner image. The output signals from each sensor are compared with each other so as to produce a differential signal. Upon presetting the difference signal to be nil for a predetermined image density, an increase or a decrease of the reference toner image will invite a change of plus/minus sign of the differential signal.

Abstract: A cut sheet feed apparatus in a recording system having recording means for performing recording at a recording position, includes first storing means for storing cut sheets to be fed to the recording position feeding means for feeding the cut sheets from the first storing means to the recording position second storing means for storing cut sheets passing through the recording position discharge means for discharging the cut sheets to the second storing means a reversible drive motor for operating the feeding means and the discharge means; and transmitting means for transmitting a forward rotational force of the drive motor to the feeding means and the discharge means to simultaneously perform feed and discharge operations, and for transmitting a reverse rotational force to the discharge means to release transmission of the rotational force to said feeding means, thereby allowing only the discharge operation.