Abstract: A sheet supplying device for supplying an uppermost sheet of a stack of sheets in a sheet cassette used in an image forming apparatus includes suction cups movable into and out of contact with the uppermost sheet in the sheet cassette, an evacuator for developing a vacuum in the suction cups to enable the suction cups to attract the uppermost sheet, a moving member for upwardly and downwardly moving the suction cups to pick up the sheet from the sheet cassette, a sheet feeding member for feeding the sheet from the moving member along a sheet feed path, and a control system for judging on the basis of a detection signal from each sensor for detecting an image forming error provided in the image forming apparatus whether the error occurs during the sheet supplying operation, and when judging that the image forming error occurs during a sheet supplying operation, the control unit ceasing the sheet supplying operation and controlling the driving of at least one of the suction cups, the evacuator, moving member an

Abstract: A printing apparatus is disclosed. A toner image is formed on an image carrier. A solvent supply device supplies a solvent to the toner image in a direction toward such a side that the toner image makes contact with an image bearing medium, the solvent lowering the viscosity of the powder image. A transfer device presses the image bearing medium against the toner image of which viscosity is lowered by the solvent, thereby transferring the toner image to the image bearing medium.

Abstract: A copier having an automatic document feeder (ADF) and selectively operable in a one-side copy mode for reproducing a document image on only one side of a paper sheet and a two-sided copy mode for reproducing document images on both sides of a paper sheet. A reversing device reverses a paper sheet undergone a copying procedure. When a tray included in the ADF is loaded with a combined stack of one-sided and two-sided documents, the condition of the back of each document is sensed by a sensor while the document is transported toward an illuminating position. The copier is automatically conditioned for the two-sided copy mode if an image is present on the back of the document or for the one-sided copy mode if otherwise. The paper sheets with images are reversed only in one of the two different copy modes before driven out of the copier.

Abstract: A laser beam printer having a scanner unit and a sheet transport apparatus for use with the scanner unit. The printer includes a sheet feeding part, a photosensitive medium, a transfer part, an upper cover and a scanner unit, the transfer part being provided at an upper portion of the photosensitive medium. The sheet transport apparatus includes an upper transport path for transporting a record sheet from the sheet feeding part to the transfer part of the printer. The sheet transport apparatus further includes a transport path where the scanner unit is provided, the transport path being provided within the upper cover.

Abstract: The present invention discloses a monocomponent developing device which comprises an image carrying member having an electrostatic latent image formed on its surface, a rotatably disposed actuating roller confronting said image carrying member, a toner transporting member formed of flexible member having a peripheral length longer than that of said actuating roller and loosely mounted thereover, said toner transporting member being an endless thin film member constructed of anisotropic electrically conductive film alternatively comprising insulated portions and electrically conductive portions which are formed by a plurality of electrodes so as to be conductive in the film width direction, and positioning means for positioning said toner transporting member in order to form a slack in the toner transporting member at a location confronting said image carrying member and bringing the slack into contact with the image carrying member.

Abstract: The number of copied sheets of paper accommodated in a staple tray for stapling process are counted by a counter. A transport path changeover member is switched over from a guide position to convey copy paper to the staple tray to a guide position to convey the copy paper to another discharge tray where stapling process is not performed corresponding to the counter value reaching the limit of stapling process. The copied sheets are, thereafter, guided to the discharge tray to continue on copying operation.

Abstract: Improvements in a device for removing the electrostatic charge on a photoconductor in an image forming apparatus. The electrostatic charge-removing device has a plurality of light-emitting diodes (LEDs) incorporated in a case. The LEDs emit diffuse light to the photoconductor to remove the electrostatic charge. The LEDs are regularly spaced from each other in a orthogonal direction to a movement direction of the photoconductor in such a way that the successive diffuse light radiations emitted from the neighboring LEDs overlap with each other. The brightness is considerably higher in the locations where the diffuse light radiations overlap with each other than in the other locations. Light-blocking members are mounted upstream of their respective light radiations as viewed in the movement direction of the photoconductor, for uniforming the brightness of light in the orthogonal direction to the movement direction of the photoconductor. This evens out the image erasure line.

Abstract: An image forming apparatus provided with an image reading unit for reading an image of an original fed into an original path, wherein the original path is confluent with a first copy sheet path connecting an image forming unit with a common tray. The image reading unit is detachable from the body of the apparatus. A copy sheet is formed an image on a first side and ejected to the common tray with the first side down. An original inserted into the original path is ejected to the common tray with its first side having an image up. Further, the apparatus has a second copy sheet path diverging from the first copy sheet path at an upstream of the original path and a sub-tray for receiving a copy sheet ejected from the second copy sheet path, and a switch member is disposed at the diverging point.

Abstract: An image density control method for an image forming apparatus of the type forming a latent image of a document image on a photoconductive element and developing the latent image to form a toner image by an electrophotographic procedure. A background pattern is implemented as a light pattern having a low density and provided independently of a reference density pattern. The light pattern is illuminated to form a latent image thereof on the photoconductive element, and the latent image is developed by a toner. The density of the resultant toner image is sensed by an image density sensor. Such a procedure allows a change in background density ascribable to contamination, increase in background potential and so forth to be detected. The light pattern may be replaced with a leading edge portion of a document if the leading edge portion has a density corresponding to the background density.

Abstract: A copying system including an image forming device for forming an image on each of the sheets, a sheet refeeding device for successively accommodating the first copied sheets, and successively refeeding same, after the first image forming is finished, to the image forming device, to form a second image thereon, the copying system inputting the number of sheets to be copied, detecting a sheet size, determining the maximum copiable number of sheets corresponding to the detected sheet size, wherein the sheet refeeding device includes a first winding device, a second winding device and a web extended on the first and second winding device, wherein the web is wound around the first winding device while supporting the sheets thereon so as to accommodate the sheets on the first winding device, and wherein the web is unwound from the first winding device and wound around the second winding device so as to feed the sheets for the image forming process.

Abstract: An automatic document conveying device to be applied to an image processor with a transparent plate on which to place document to be processed being disposed on the upper surface of a housing. The automatic document conveying device comprises a document table, a document introduction passage extending from the document table to one end edge of the transparent plate, a first document receiving tray, a second document receiving tray and a document delivery passage. The document delivery passage includes a common passage extending from the other end edge of the transparent plate, a first branched passage extending from the downstream end of the common passage to the first document receiving tray, and a second branched passage extending from the downstream end of the common passage to the second document receiving tray.

Abstract: In a heat roll consisting of a mandrel and a surface layer, this invention comprises a fixing apparatus and a recording apparatus, wherein a thickness of the surface layer is formed not exceeding the thickness determined by a square root of the product of a heat diffusion rate of the surface material and a nip time required for a form to pass a nip zone, and a thickness of the mandrel is formed not less than the thickness determined by a square root of the product of a heat diffusion rate of the mandrel material and a one rotational period of the mandrel. Since the surface layer and the mandrel are so specified for the thickness as mentioned, a quantity of heat flowing from the mandrel into the surface layer multiplies, and thus a high fixing strength is obtainable. The fixing apparatus and the recording apparatus are provided further with a cleaning device high in cleaning capacity.

Abstract: A wet-type image formation apparatus comprising (i) a belt-shaped photoconductor prepared by depositing a photoconductive material on the outer surface of a belt-shaped substrate; (ii) a plurality of pulleys which support and drive the belt-shaped photoconductor; (iii) a charging unit; (iv) an exposure unit; (v) a development unit; (vi) an image transfer unit; (vii) a squeeze roller unit, comprising a pair of roller-supporting members and a co-axial roller; (viii) a cleaning means; (ix) a liquid developer removing unit which is provided inside the belt-shaped photoconductor, capable of removing the liquid developer dropping onto the inner surface of the belt-shaped photoconductor and recovering it in a liquid developer reservoir or a development unit.

Abstract: An electrophotographic copier or similar image forming apparatus having a photoconductive drum and a developing unit having a developing roller which is pressed against the drum. The developing unit is removably mounted on a body of the apparatus and arranged such that reaction forces exerted in the vertical direction by the copier body on the developing unit are directed upward at all times. When the pressing contact of the developing roller with the drum is cancelled, the developing unit is held in a retracted position where it is spaced apart from the drum.

Abstract: In a high speed electrophotographic printing apparatus and method wherein a charge of desired polarity and potential is applied uniformly to a photoconductive surface of a rapidly rotating drum, an improvement is provided which comprises an electrometer located adjacent the drum surface for sensing and measuring the charge imparted to the surface. The electrometer is operatively connected through a programmable logic controller to a variable power output that drives the corona array to impart the charge to the drum surface. Irregularities in charge potential imparted to the surface are thereby measured by the electrometer with appropriate adjustment being made in the charge applied to the drum by the corona array.

Abstract: An electrophotographic device includes a flexible belt-type charge retentive member, bearing a developed latent image and brings a sheet of paper or other transfer member into intimate contact with the charge retentive surface at a transfer station for electrostatic transfer of toner from the charge retentive surface to the sheet. At the transfer station, a resonator suitable for generating vibratory energy is arranged in line contact with the back side of the charge retentive, to uniformly apply vibratory energy to the charge retentive member surface at a position opposite the transfer coronode or peak transfer field, or slightly upstream therefrom. Toner is released from the electrostatic and mechanical forces adjering it to the charge retentive surface at the line contact position.

Abstract: A copying apparatus includes a housing in which are arranged an image carrier and an exposure unit both for emitting light to an original placed on the original stand to form an electrostatic latent image on the image carrier and for emitting light to the image carrier to erase the electrostatic latent image. The exposure unit includes a lamp having light emitting portions and non-light emitting portions which are alternately connected together. A reflector is located around the lamp and directs the light emitted from the lamp toward the original. The reflector has a plurality of openings formed to face the lamp, so that part of the light emitted from the lamp passes through the openings and is directed to the image carrier. The reflector has a plurality of connecting portions facing the non-light-emitting portions and located between adjacent ones of the openings.

Abstract: A sheet transporting apparatus comprising an outlet for sheets, a first path through which sheets ejected from a copying machine are transported in a first direction, to the outlet and in a second direction to be reversed from the outlet, a diverter for diverting the travel of sheets, which is disposed in the vicinity of the outlet and movable between a first position where sheets traveling in the first direction are guided to a handling apparatus attached at the outlet and a second position where sheets are guided to a space between respective outside frames of the transporting apparatus and the handling apparatus, a second path for receiving sheets traveling in the second direction along the first path and transporting the sheets, a storing unit wherein sheets transported through the second path are stored and a refeeding section for feeding sheets stored in the storing unit to the copying machine.

Abstract: Dry toner development of an electrostatic charge pattern on a recording surface is carried out with a dry toner layer formed on a donor member by electrostatic attraction resulting from a DC voltage applied across a gap between the surface of the donor member 22 and the surface of an upstream electrically conductive member 16 covered with a mixture of triboelectrically charged toner particles and magnetic carrier particles, the latter with adhering toner particles being attracted to the electrically conductive member surface by magnetic force and forming thereon a magnetic brush. The DC voltage in the gap causes selective attraction of the toner particles free of magnetic carrier particles and an AC voltage of lower peak magnitude can be superimposed on the DC voltage to set the particles in the gap in vibration and facilitate transfer across the gap.

Abstract: An improved developing system for an electrophotographic color imaging apparatus is disclosed which selectively moves multiple individual developing units from a plurality of first storage positions to the same working or operating position in a processing path to color develop the latent image. The developing system stores the individual developing units remotely from the processing path. The individual toner developing units move in both horizontal and vertical directions as they move from the first storage positions to the second working or operating position. The working position is the same distance and time from the charging and depressant coronas in the process path that is followed to produce a colored image.