Abstract: An electronic device includes a first electrode, a second electrode, a third electrode, a first resistor, a second resistor, and an attachment/detachment detecting portion. The first electrode and the second electrode are separated from each other upon an attachment of a detachable member. The third electrode comes into contact with the first electrode upon the attachment of the detachable member. The first resistor is arranged on a conduction path that extends from a power supply to the first electrode. The second resistor is arranged on either a first conduction path or a second conduction path, the first conduction path extending from the second electrode to a ground, the second conduction path extending from the third electrode to the ground. The attachment/detachment detecting portion detects attachment state of the detachable member based on a voltage applied to the first electrode.

Abstract: An electronic device includes a first electrode, a second electrode, a third electrode, a first resistor, a second resistor, and an attachment/detachment detecting portion. The first electrode and the second electrode are separated from each other upon an attachment of a detachable member. The third electrode comes into contact with the first electrode upon the attachment of the detachable member. The first resistor is arranged on a conduction path that extends from a power supply to the first electrode. The second resistor is arranged on either a first conduction path or a second conduction path, the first conduction path extending from the second electrode to a ground, the second conduction path extending from the third electrode to the ground. The attachment/detachment detecting portion detects attachment state of the detachable member based on a voltage applied to the first electrode.

Abstract: An image forming apparatus includes: an optical sensor which includes a light-emitting part and a light-receiving part opposed to the light-emitting part and is configured to detect an amount of waste toner accumulated in a waste toner container, the waste toner being produced with formation of an image and then accommodated in the waste toner container; a detecting section configured to detect a change in an output of the light-receiving part; a shielding member interposed between the light-emitting part and the light-receiving part and configured to create, between the light-emitting part and the light-receiving part, a light-transmitting environment equivalent to that when the waste toner container is filled with the waste toner; and an adjusting section configured to adjust a light intensity of the light-emitting part when the shielding member is interposed between the light-emitting part and the light-receiving part.

Abstract: An image forming apparatus includes: an optical sensor which includes a light-emitting part and a light-receiving part opposed to the light-emitting part and is configured to detect an amount of waste toner accumulated in a waste toner container, the waste toner being produced with formation of an image and then accommodated in the waste toner container; a detecting section configured to detect a change in an output of the light-receiving part; a shielding member interposed between the light-emitting part and the light-receiving part and configured to create, between the light-emitting part and the light-receiving part, a light-transmitting environment equivalent to that when the waste toner container is filled with the waste toner; and an adjusting section configured to adjust a light intensity of the light-emitting part when the shielding member is interposed between the light-emitting part and the light-receiving part.

Abstract: A developing device includes a developing roller, a magnetic roller, a capacitor, a transformer, and a switching portion. The magnetic roller supplies toner to the developing roller or takes off the toner from the same. The capacitor is connected to a primary of the transformer, and the developing roller is connected to a secondary of the same. During a period while the voltage between electrodes of the capacitor is changing, the switching portion changes the duty ratio in a predetermined second time slot in which current flowing in the switching portion is smaller than that flowing in a first time slot.

Abstract: A sheet transport device comprises a sheet feeding path through which a sheet is transported, first and second elements which are located face to face with a particular point in the sheet feeding path and have first and second surfaces, respectively, constituting part of the sheet feeding path and arranged therealong, an interposed element disposed insertably into and withdrawably from a space formed between the first and second elements, and a discharge arrester disposed in first and second surfaces for providing protection against a discharge of static electricity from the sheet, the discharge arrester having a projecting part extending in a direction intersecting the sheet feeding path.

Abstract: A sheet transport device comprises a sheet feeding path through which a sheet is transported, first and second elements which are located face to face with a particular point in the sheet feeding path and have first and second surfaces, respectively, constituting part of the sheet feeding path and arranged therealong, an interposed element disposed insertably into and withdrawably from a space formed between the first and second elements, and a discharge arrester disposed in first and second surfaces for providing protection against a discharge of static electricity from the sheet, the discharge arrester having a projecting part extending in a direction intersecting the sheet feeding path.

Abstract: In a cooling device of an image forming apparatus, a space is formed between a flat surface of a sheet metal attached on a circuit board attached part and a power source circuit board. A duct is formed by a shielding member formed in a U shape surrounding the space, and on the lower part of the flat surface of the sheet metal, a tubular part as an air outlet is formed so as to be elongated to the side of a main body. On the upper part of the sheet metal arranged in a vertical direction, a fan motor is mounted, which sends cooled air into the power source circuit board and the duct. The cooled air cools the power source circuit board and also cools a power source unit in the main body via the tubular member.

Abstract: An image forming apparatus includes: an image forming section; a discharger for discharging and guiding the copying paper to an outlet; and a controlling section for operating the image forming section, based on an image forming instruction from an operation section. A data fetching section fetches first image data on a plurality of pages and second image data on a plurality of pages. The operation section accepts, as the image forming instruction, a sheaf-unit sorting instruction which includes a predetermined number of copies of each of the first image data and second image data and sorting of the copies. The controlling section, based on the sheaf-unit sorting instruction executes, for the predetermined number of copies, an operation of guiding the first and second sheafs of copying paper, in sequence, to the outlet so that the first sheaf and second sheafs of copying paper are piled in order.

Abstract: In a cooling device of an image forming apparatus, a space is formed between a flat surface of a sheet metal attached on a circuit board attached part and a power source circuit board. A duct is formed by a shielding member formed in a U shape surrounding the space, and on the lower part of the flat surface of the sheet metal, a tubular part as an air outlet is formed so as to be elongated to the side of a main body. On the upper part of the sheet metal arranged in a vertical direction, a fan motor is mounted, which sends cooled air into the power source circuit board and the duct. The cooled air cools the power source circuit board and also cools a power source unit in the main body via the tubular member.

Abstract: An image forming apparatus includes: an image forming section; a discharger for discharging and guiding the copying paper to an outlet; and a controlling section for operating the image forming section, based on an image forming instruction from an operation section. A data fetching section fetches first image data on a plurality of pages and second image data on a plurality of pages. The operation section accepts, as the image forming instruction, a sheaf-unit sorting instruction which includes a predetermined number of copies of each of the first image data and second image data and sorting of the copies. The controlling section, based on the sheaf-unit sorting instruction executes, for the predetermined number of copies, an operation of guiding the first and second sheafs of copying paper, in sequence, to the outlet so that the first sheaf and second sheafs of copying paper are piled in order.

Abstract: An image forming apparatus includes a data fetching section that fetches first image data on a plurality of pages and second image data on a plurality of pages. An operation section accepts a sheaf-unit sorting instruction, which includes a predetermined number of copies of each of the first image data and second image data. A controlling section conducts finishing processing of each of a first sheaf of paper on which the first image data is copied and a second sheaf of paper on which the second image data is copied based on the sheaf-unit sorting instruction. The controlling section then guides the first sheaf of paper and the second sheaf of paper, in sequence, to the outlet so that the first sheaf of paper and the second sheaf of paper are piled in this order.

Abstract: An image forming apparatus includes a data fetching section that fetches first image data on a plurality of pages and second image data on a plurality of pages. An operation section accepts a sheaf-unit sorting instruction, which includes a predetermined number of copies of each of the first image data and second image data. A controlling section conducts finishing processing of each of a first sheaf of paper on which the first image data is copied and a second sheaf of paper on which the second image data is copied based on the sheaf-unit sorting instruction. The controlling section then guides the first sheaf of paper and the second sheaf of paper, in sequence, to the outlet so that the first sheaf of paper and the second sheaf of paper are piled in this order.

Abstract: In an image forming apparatus which uses a hollow space between an image reading section provided in an upper part of the apparatus and an image forming section provided in a lower part of the apparatus as a paper output space, the hollow space is used also as a space for temporarily holding a sheet of paper during a switchback operation. This arrangement helps prevent physical contact between the paper and the body of an operator or other objects and makes it easier to deal with a paper jam which is likely to occur during the switchback operation.

Abstract: Image forming apparatus including a paper return device for feeding a sheet of paper ejected from a paper output port opening in a main body of the apparatus to its outside back to a paper feeding port also opening in the main body to its outside. For double-sided copying operation, the sheet of paper ejected from the paper output port carrying an image on one side only is returned to the paper feeding port and fed again to an image former from the paper feeding port so that it is not necessary to provide a dedicated paper path for re-feeding the paper. The apparatus includes a paper sensor which senses the paper inserted into the paper feeding port and outputs a paper sensing signal, a discriminator for judging whether the paper return device is in an operating condition, and a paper feed controller which controls a driver for driving a paper feeder such that the paper feeder initiates a paper feed operation when the paper sensing signal is output while the paper return device is in its operating condition.

Abstract: A transfer roller is spaced away from the outer surface of a photosensitive drum by a specified distance to prevent the abrasion and damage of the photosensitive drum by the contact of the transfer roller and the photosensitive drum. The transfer roller not in contact with the photosensitive drum can be formed to have a sufficient hardness without damaging the outer surface of the photosensitive drum. Further, since the transfer roller has a sufficient hardness, cleaning blades can be held in without damaging the transfer roller with a sufficiently large force without damaging the transfer roller, thereby securely scraping off toner and the line adhered to the transfer roller and preventing the rear surface of a transfer sheet from being smeared.

Abstract: A document feeder to be mounted atop an image reading device having a stationary optical system disposed under a contact glass. The document feeder includes a document original plate for holding thereon document originals, a document original feeding mechanism for feeding a document original from the document original plate onto a contact glass, a document original transporting mechanism for transporting the document original fed by the document original feeding mechanism along the upper surface of the contact glass, a document original discharging mechanism for discharging the document original transported by the document original transporting mechanism, and a document original discharge plate for receiving the document original discharged by the document original discharging mechanism. The document original feeding mechanism, the document original transporting mechanism and the document original discharging mechanism are integrally supported in a unit body to constitute a single unit.

Abstract: A sheet feeding apparatus having a feeding roller for feeding a sheet, a support shaft forwardly and reversely rotatable integrally with the feeding roller and a stopper disposed upstream of the feeding roller in the sheet feeding direction for temporarily regulating the feed of a sheet to the feeding roller. When the rotation in one direction of the feeding roller is transmitted to a locking member through a one-way clutch, the locking member is rotated to lock the stopper. When the feeding roller is rotated in the opposite direction, the locked state of the stopper is released.

Abstract: In an image forming apparatus, a sheet that has been transported in a certain direction is selectively transported to one of first and second transport routes by a route changer mechanism. A first cover and a second cover are openably provided on a main body of the apparatus to respectively allow the first and second transport routes to be accessible to outside of the apparatus main body when set in an opened state. An operative mechanism is provided to open the first cover in association with opening of the second cover.

Abstract: An image forming apparatus has an optical system, an image forming section and a paper conveying section provided in its main body. The main body includes a first portion containing the optical system and a second portion containing the image forming section and the paper conveying section below the first portion. A paper discharging section opening toward the front is provided between the first portion and the second portion. The first portion is shifted by a predetermined amount backward with the position where it is lined up to a second portion as a basis. It is easy to visually confirm whether or not there is a paper sheet in the paper discharging section below the first portion.