Abstract: A cascade scanning optical system which includes a plurality of laser scanning optical systems each emitting a laser beam to scan a surface of a member, and a beam splitter positioned in an optical path between the plurality of laser scanning optical systems and the member such that a first laser beam which has passed through the beam splitter and a second laser beam which has been reflected by the beam splitter proceed to the surface on a common line thereon in respective ranges of the common line. Each of the plurality of laser scanning optical systems is desinged as a telecentric system.

Abstract: A fixing unit includes a heat roller accommodating a heater and a press roller movable toward and away from the heat roller. Both shaft members of the heat roller are supported by two receiving members, with a clearance provided between each shaft member and respective receiving member. A driven gear is provided to one of the shaft member, which engages a rotating mechanism for rotating the heat roller. The fixing unit further includes a biasing member which biases the other shaft of the heat roller away from the press roller within the clearance, in such a manner that the heat roller and the press roller become parallel when the above-described one shaft member is urged away from the press roller due to the meshing engagement of the driven gear and the rotating mechanism.

Abstract: A printer includes a tractor unit for feeding continuous form paper, encoders driven in synchronization with the tractor unit, and detecting sensors for detecting the encoders to generate feed pulses at a standard interval. The printer further includes a paper top sensor for detecting a leading edge of the continuous form paper to generate paper top signal and is arranged to control the feed of the paper based on the feed pulse generated after the paper top signal. In order to adjust the printing position on the paper in case where the scanning position is misaligned due to a manufacturing error, the position of the detecting sensors is adjustable with respect to the encoders to compensate for the error. Further, the position of the paper top sensor is adjustable with respect to the tractor unit in order to keep the relationship between the feed pulse and the paper top signal unchanged regardless of the adjustment of the detecting sensors.

Abstract: A fixing unit includes a heat roller accommodating a heater and a press roller movable between an operating position in which the recording sheet is nipped by the rollers and a retracted position. A driven gear is provided to one axial end of heat roller, which engages a rotating mechanism for rotating the heat roller. An opening/closing mechanism is arranged to move a first axial end (at the same side as the driven gear of the heat roller) of said press roller to said operating position before moving a second axial end of the press roller to the operating position.

Abstract: A cascade scanning optical system which includes: a pair of laser scanning optical systems each having a laser beam emitter and a laser beam deflector, wherein a laser beam emitted by the laser beam emitter enters the laser beam deflector so that the laser beam deflector deflects the laser beam to scan a surface of a member such that the laser beams proceed to the surface on a common line thereon in respective ranges of the common line; a pair of mirrors respectively provided in the pair of laser scanning optical systems, each of the pair of mirrors being positioned in a corresponding optical path between the laser beam deflector and the member to reflect a laser beam incident thereon toward the surface; a pair of cylindrical lenses having power in a sub-scanning direction, respectively provided in the pair of laser scanning optical systems, each of the pair of cylindrical lenses being positioned in a corresponding optical path between the laser beam emitter and the laser beam deflector; first means for adjus

Abstract: A cascade scanning optical system which includes a first laser scanning optical system for emitting a first laser beam to scan a surface of a member to generate a first scanning line, and a second laser scanning optical system for emitting a second laser beam to scan the surface to generate a second scanning line, wherein the first and second laser scanning optical systems are arranged so as to combine the first scanning line with the second scanning line at a point of contact therebetween in a main scanning direction to form a single scanning line, and wherein each of the first and second laser scanning optical systems is designed as a non-telecentric system through which the incident angle of a corresponding one of the first and second laser beams relative to the surface varies in accordance with a variation in the position of a scanning spot of the corresponding one of the first and second laser beams on the surface in the main scanning direction, and further wherein an incident angle of each of the first

Abstract: A sheet guide mechanism is provided with a guide path along which a sheet-like member is guided and which is defined between one and the other guide surfaces. A stationary guide member has a first surface defining the one guide surface, and a movable guide member having a second surface defines the other guide surface, which is shiftable relative to the stationary guide member. Protrusions are formed on one of the first and second surfaces, protruding toward the other of the first and second surfaces by a predetermined distance. A shiftable member is shiftable relative to the stationary guide member between a guide position and a remote position. A spring is provided between the shiftable member and the movable guide member allowing the elastic contact between the protrusions and the other of the first and second surfaces, when the shiftable member is located in the guide position.

Abstract: A color printer includes a single laser scanning unit which is controlled to emit a scanning laser in accordance with color image data on each of a plurality of separated colors to be printed. A plurality of photosensitive drums, whose number corresponds to the number of colors to be printed, a laser scanning unit driver which moves the laser scanning unit to transfer positions corresponding to the photosensitive drums, and a plurality of developing units corresponding to the photosensitive drums are provided, to develop latent images drawn on the photosensitive drums by the laser emitted from the laser scanning unit, using a toner of each color. An endless transfer belt has a transfer surface which is successively moved to the transfer positions, and a transfer device which successively transfers the toner images developed by the developing units on the photosensitive drums, onto the same transfer surface of the transfer belt are also provided.

Abstract: An electrophotographic apparatus is provided with an original separation mechanism which is disposed on a lower side of the inlet port of a feeding path. The original separation mechanism is pressed to an original pick-up roller, and is provided for separating one original, which contacts the original pick-up roller, from at least one following original. The original separation mechanism includes a unit body, and a friction member attached to the upper surface of a unit body, extending toward a downstream side of the feeding direction of the original so as to intersect the feed path at a predetermined angle, and having an upper surface with a prescribed friction coefficient. The original separation mechanism further includes a pair of supporting members attached to both sides of the unit body with respect to the friction member, and each formed of a spring material having an upper surface which extends so as to intersect the upper surface of the lower original guide member at a predetermined angle.

Abstract: An electrophotographic apparatus is provided with a photoconductive drum including an outer peripheral surface on which a latent image corresponding to an image to be transferred is formed, and a developing device for developing the latent image by a toner. The electrophotographic apparatus further includes a housing for rotatably supporting the photoconductive drum therein and having an opening on one side, a cover member for releasably closing the opening of the housing, and a transfer charger which is attached to one surface of the cover member opposing to the photoconductive drum, and which is provided for transferring the developed image onto a sheet-like member. A pre-roller is attached to an upstream end of a housing which houses the transfer charger. The pre-roller and the photoconductive drum are positioned relative to each other so that a gap of predetermined dimension is defined therebetween.

Abstract: In a sheet warp prevention mechanism adapted to be positioned in an imaging device for forming a visible image, the imaging device includes a pair of rollers adapted to be brought into and out of contact with each other in accordance with a rocking operation of one of the pair of rollers about a predetermined shaft member. The one of the pair of rollers which is arranged to be rotated in a predetermined direction for feeding the continuous sheet has a gear member coaxially provided therewith which is brought into engagement with another gear member coaxially provided with the shaft member about which the roller rotates. A driving source for driving both the one of the pair of rollers and a feeding member for feeding the continuous sheet toward the pair of rollers, and a transmitting mechanism for transmitting the driving force toward the pair of rollers is also included.

Abstract: A sheet holding mechanism is provided for receiving and stacking sheets, such as recording papers, ejected from a main apparatus such as, for instance, a printer. The mechanism comprises an ejected sheet tray provided with the main apparatus that is swingable in a predetermined range. The tray is lockable by locking means at every predetermined angle in the predetermined swingable range of the tray. Guide roller means are provided with the main apparatus for leading the sheets ejected from the main apparatus to the tray and are arranged to be swingable in response to a swinging movement of the tray.

Abstract: A paper feed mechanism is provided for individually supplying recording papers to an imaging apparatus. A plurality of papers are stacked on a tray member of a paper cassette. One end of the tray member is biased toward a feeding roller and presses the stacked papers toward the feeding roller. The papers are fed one by one upon rotation of the feeding roller. A swingable guide member is mounted on the paper cassette to cover the stacked papers. By swinging the guide member, the stacked papers, as well as the tray member, are downwardly moved away from the feeding roller, so that a spacing is formed between the feeding roller and the stacked papers. One or more other recording papers can be inserted into the spacing, to be fed by the feeding roller instead of the stacked papers.

Abstract: A detection mechanism for detecting an installation of a detachable member to a main body, includes a movable member provided on the detachable member and being movable between a first position and a second position. The movable member is set in the first position prior to a first installation of the detachable member to the main body. A detecting switch, provided on the main body, detects the movable member in the first position but is incapable of detecting the movable member in the second position. An actuating member, provided on the main body causes the movable member to move from the first position to the second position when the detachable member has been installed into the main body. A locking mechanism locks the movable member to the second position after the actuating member actuates the movable member to the second position. The detecting switch detects only a first installation of the detachable member.

Abstract: An electrophotographic apparatus is provided with a control device for controlling the heating temperature of the fixing unit in accordance with the detected result by use of a condition detection mechanism. The control device controls the fixing unit: (a) to set the heating temperature thereof to a fixing possible temperature when the condition detection device detects that the imaging operation of the imaging device is initiated or has been continuing, (b) to set the heating temperature to a stand-by temperature lower than the fixing possible temperature when the condition detection device detects that a stand-by condition, in which the imaging operation is interrupted, continues for a first predetermined time, and (c) to set the heating temperature to a save-energy temperature, lower that the stand-by temperature, when the condition detection device detects that the stand-by condition has been continuing for a second predetermined time.

Abstract: A printer, for printing on continuous recording paper, includes tractors disposed in the recording paper feed path of the printer, with each of the tractors circumferentially travelling in synchronism with movement of the continuous recording paper when the tractors engage feed holes of the continuous paper. When no printing operation is performed, travel of the tractors can be prevented by operation of an electromagnetic clutch, or a combination of one way clutches. Further, the printer uses an electrophotographic method wherein when no printing operation is performed, a transfer charger or fixing roller can be retracted from an operational position. A lever, associated with movement of the transfer charge or fixing roller, is pressed against and locked with the pulley fixed to the rotating shaft of each of the tractors to thereby prohibit the movement of the tractor.

Abstract: A doctor blade mounting structure for mounting a doctor blade to a main body of a development device is provided, which includes a development roller which is rotatably arranged in the main body and on the outer circumferential surface of which a magnetic brush is formed. The doctor blade is disposed in confrontation with the development roller with a predetermined gap defined between the distal end of the doctor blade and the outer periphery of the development roller, for setting the height of the magnetic brush to a uniform level. The mounting structure is provided with a rigid support plate to which the doctor blade is attached, and fixing screws for fixing the rigid support plate to the main body of the development device are provided. The doctor blade is mounted to the main body of the development device through the support plate.

Abstract: A gear arrangement for a development unit of an imaging device employing an electrophotographic process. The development unit is provided with a rotation member and swingably supported by the main body of the imaging device through a support shaft to be mounted on a predetermined position of the main body of the imaging device. An input gear is provided on the development unit and coupled with the rotation member thereof to be meshed with a drive gear provided with the imaging device. The rotational force of the drive gear is transmitted to the input gear to thereby rotate the rotation member. The drive gear and the input gear are disposed such that a line obtained by extending a line of action as a moving locus of the point at which the tooth of the drive gear is in contact with the tooth of the input gear is substantially directed to the direction of the support shaft through which the development unit is supported by the main body of the imaging device.

Abstract: A wrinkle prevention structure is employed in an electrophotographic imaging device using a continuous form recording sheet. The structure is provided with a guide member disposed on the upstream side of a pair of fixing rollers. The guide member has a guide surface extending substantially horizontally for guiding the recording sheet toward a nip between the pair of fixing rollers, and a tension surface arranged on downstream side of the guide surface. The upstream side end of the tension surface is connected with the downstream side end of the guide surface, the downstream side end of the tension surface is formed substantially arc-shaped, and the tension plane is upwardly inclined with respect to the guide surface.

Abstract: An electrophotographic facsimile apparatus is provided with a main body, a recording mechanism substantially arranged in the main body, for printing received image information onto a recording paper fed through a recording paper path by using electrophotography, and an upper structure is disposed on the main body. The electrophotographic facsimile apparatus further includes an image recording head disposed in the upper structure for reading image information of a document to be transmitted, and an operation unit for inputting operation information. The recording paper path is formed between the main body and the upper structure, and inclines obliquely downward along a direction in which the recording paper is fed. The upper structure has an inclined upper surface parallel with the recording paper path. The operation unit is disposed on the inclined upper surface of the upper structure.