Abstract: A color image forming apparatus of the present invention includes a deflector for deflecting a laser beam in order to form images of different colors. Pattern images for measurement are formed on sheet conveying means in the different colors. A sensor senses the positions of the pattern images. A counter and a computing circuit cooperate to determine the amount of shift of each pattern image from a particular reference position. To correct the shift of each pattern image, a write timing generator adjusts a write start timing while a beam shift driving circuit adjusts a writing position.

Abstract: A color image forming apparatus of the present invention includes a deflector for deflecting a laser beam in order to form images of different colors. Pattern images for measurement are formed on sheet conveying means in the different colors. A sensor senses the positions of the pattern images. A counter and a computing circuit cooperate to determine the amount of shift of each pattern image from a particular reference position. To correct the shift of each pattern image, a write timing generator adjusts a write start timing while a beam shift driving circuit adjusts a writing position.

Abstract: An optical scanning device including a housing, a first carriage carrying a light source and a first mirror, a second carriage carrying second and third mirrors, the second carriage configured to move in a sub-scanning direction at one-half of a speed of the first carriage, first and second timing pulleys spaced apart in the sub-scanning direction, a timing belt spanned around the first and second timing pulleys to reciprocate the first carriage in the sub-scanning direction, a drive device to drive the first timing pulley, flat pulleys supported by the second carriage and spaced apart in the sub-scanning direction by a moving distance of the second carriage, a flat belt spanned around the flat pulleys to reciprocate the second carriage in the sub-scanning direction, an engaging member engaging the timing and flat belts to the first carriage, and a fixing member fixing the flat belt to the housing.

Abstract: This recording-medium conveying device comprises a conveying belt, the conveying belt, a belt charging unit, and a pressing roller. The conveying belt is wound around a driving roller and a driven roller so as to convey a recording medium to an image recording part. The conveying belt includes an insulating layer formed at one side contacting the recording medium. The belt charging unit is provided in contact with the insulating layer so as to charge the insulating layer with a positive charge and a negative charge alternately in a moving direction of the conveying belt by applying an AC bias to the conveying belt. The pressing roller presses the conveying belt against the driving roller so as to prevent the conveying belt from slipping on the driving roller.

Abstract: A method for turning over a page of a book-type original using a belt as a device for turning over the page. The original is set with spread pages arranged upward. The method includes the steps of disposing the belt over spread pages of the original so that the belt comes in contact with a surface of the spread pages, attracting one of the spread pages of the original to the belt by an attracting devices, and deforming a part of the belt upward at a portion of the belt continuously along the surface of the spread pages while moving the portion from one end of the page to the other end thereof so that the page attracted to the belt is separated from a next page of the original.

Abstract: An image reading device capable of preventing, by increasing the quantity of light at the center or bound portion of a spread book document, the quantity of light from becoming short and preventing density from becoming irregular due to the deviation of a focus. At and around the center of a spread book document where the document is bound, the quantity of light for illumination or the amplification gain of image data read from the document is increased. A plurality of fluorescent lamps illuminate the surface of the document at the upstream side and downstream side with respect to an intended scanning direction. When the edge of the document is to be detected, only one of the lamps is turned on to enhance the stripe pattern representative of the stepped edge portion of the document.

Abstract: An image reading device capable of preventing, by increasing the quantity of light at the center or bound portion of a spread book document, the quantity of light from becoming short and preventing density from becoming irregular due to the deviation of a focus. At and around the center of a spread book document where the document is bound, the quantity of light for illumination or the amplification gain of image data read from the document is increased. A plurality of fluorescent lamps illuminate the surface of the document at the upstream side and downstream side with respect to an intended scanning direction. When the edge of the document is to be detected, only one of the lamps is turned on to enhance the stripe pattern representative of the stepped edge portion of the document.

Abstract: An image reader capable of determining whether or not a book document to be copied needs royalty by the recognition of a book document and counting operation of a copying system. When a book document to be copied needs royalty, the number of times that images of the document are scanned or the number of times that the resulting image data are outputted is counted. While the count is stored, the royalty of the book document copied is managed on the basis of the count. The image reader can also read a ID code formed on the book, and can control the counting operation based on the detected book ID.

Abstract: A miniature and reliable device capable of reading a book document while turning the pages thereof. A book document is laid on a document table in a spread position face up. The document table is pressed upward while a scanning unit is restricted in movement in the up-and-down direction. The scanning unit, therefore, receives the surface of the book document pressed upward.

Abstract: In a book document reading device having a page turning capability, a scanning and page turning device scans a spread book document and turns over a leaf by receiving and then sending it out from a receiving section. The device is capable of surely detecting the edges of the book document.

Abstract: In an image forming apparatus capable of reading a book document while turning over pages of the book, image data representative of two spread pages of a book document are stored in a frame memory. Among the image data, image data matching the front of a sheet are read out of the frame memory first and then output on the front of a fresh sheet. Then, an image is formed on the rear of a sheet refed from a duplex copy tray or refeed tray. Alternatively, an arrangement may be made such that, among two pages of image data, the image data read last are out of the frame memory first and then output on the front of a fresh sheet, and then an image is formed on the rear of a sheet refed from the refeed tray.

Abstract: In a book document reading device having a page turning capability, a turn belt has a flat portion at the underside thereof and is supported by a turn roller. The turn roller selectively moves the turn belt to a first position where the flat portion of the belt electrostatically attracts the uppermost leaf of a book document, which is spread on a table, in contact with the leaf, or to a second position where the belt is spaced apart from the book document while carrying the uppermost page therewith. When the turn belt is moved from the first position to the second position, a scanning unit is caused to stop moving. This allows the leaf of the document to surely adhere to the turn belt.

Abstract: A method for turning over a page of a book-type original using a belt as a device for turning over the page. The original is set with spread pages arranged upward. The method includes the steps of disposing the belt over spread pages of the original so that the belt comes in contact with a surface of the spread pages, attracting one of the spread pages of the original to the belt by an attracting devices, and deforming a part of the belt upward at a portion of the belt continuously along the surface of the spread pages while moving the portion from one end of the page to the other end thereof so that the page attracted to the belt is separated from a next page of the original.

Abstract: An image reader for reading a book document laid on a document table in a spread position by optically scanning the surface of the document. The edge of the document on the side where scanning for reading the document starts, the position of an image on the document, the size of the document, the edge of the document on the side where the leaf of the document begins to be turned over and so forth are detected on the basis of data derived from the optical scanning of the surface of the document.

Abstract: A sheet feeding and separting device incorporated in image forming equipment for feeding sheets one by one from a sheet stack while preventing two or more sheets from being fed together as far as possible and, when a plurality of sheets are accidentally fed together, surely separating one of them from the others. A pick-up member is implemented as an endless dielectric belt. An AC power source forms a charge pattern on the belt via an electrode. As a result, the belt retains a sheet by attraction and transports it due to the Maxwell stress generated in the sheet. When a plurality of sheets are fed together, an arresting member which faces the belt separates one of them from the others. Alternatively, a charge pattern may be formed on the surface of the arresting member.

Abstract: An electrophotographic copier, laser printer, facsimile transceiver or similar image forming apparatus of the type having a rotary polygonal mirror. The apparatus detects a position where a laser beam is incident on a photo-conductive element in both a main scanning direction and a subscanning direction. Based on the detected incident position of the laser beam on the photo-conductive element, the laser beam is deflected to produce high quality images free from banding, which can be caused by any one of an irregular configuration of the polygonal mirror, a variation in the moving speed of a photoconductive element, or a variation in the position where a laser beam is incident due to mechanical vibrations.

Abstract: A finisher operable with an image forming apparatus for discharging paper sheets coming out of the apparatus and each carrying an image thereon to a plurality of bins while sorting the paper sheets and, if desired, packaging the paper sheets in an envelope. When a pack mode is selected, the size of paper sheets and the sizes of envelopes which are to be fed from a paper cassette or a tray each are sensed by size sensors. Envelopes sizes capable of accommodating the paper sheets of the sensed size are determined and compared with the sensed envelope sizes. Among the determined envelope sizes, the envelope size capable of accommodating the paper sheets of the size sensed by the size sensor in a desired number inputted. When the desired number is too great to be packaged in the envelope, such an occurrence is displayed and/or the pack mode is cancelled.

Abstract: Image forming equipment having an image carrier and a developer carrier located face-to-face and forming an AC-superposed DC electric field between them to develop a latent image electrostatically formed on the image carrier. Sensors responsive to image forming conditions are provided and protected from noise ascribable to an AC component included in the electric field in the event when the sensors operate.

Abstract: A feeder of an image forming apparatus which includes a storing device for storing a stack of recording mediums and an endless belt to be used in the conveyance of a recording medium to an image forming section of the apparatus. A speed control device is provided for varying the speed of the endless belt driven by a driving device when a portion of the endless belt passes the storing device. Also provided are a plurality of pickup rollers which are disposed adjacent to the endless belt in correspondence with each respective storage device for moving the endless belt into engagement with a foremost recording medium in the storing device in order to convey the recording medium to the image forming section.

Abstract: An image forming apparatus having a developing device of the type using a two-component type developer and developing an electrostatic latent image by a bias electric field having an alternating electric field. A predetermined reference latent image is electrostatically formed on an image carrier by a reference latent image forming device and then developed by the developing device to become a reference toner image. An irregularity detecting circuit determines the degree of difference between the density of the edge and the density of the central portion of the reference toner image. A bias electric field control circuit controls the bias electric field in matching relation to the output of the irregularity detecting circuit, thereby preventing the image quality from being degraded by a change in the resistance of the carrier.