Abstract: In an optical detecting device, used for an image forming apparatus, for detecting an object to be detected, such as a paper, by an optical means including a light emitting means 20c, a photo sensing means 20d, a reflecting means 20b, and the like, there is provided at least one of a paper detecting devices in which conductive attracting means connected to a predetermined potential is disposed close to the optical means, the optical means is attached to a periodical replacing component of the image forming apparatus, a reflecting means 20b and a paper transporting path are oriented in different directions with respect to a photo sensing means 20d and a distance from the light emitting means 20c and the like to the reflecting means 20b is different from a distance from the light emitting means 20c and the like to the paper transporting path.

Abstract: An object of the present invention is to provide an image forming apparatus capable of preventing vibration of a transfer film caused from the operation of a separating device to prevent irregular density distribution and change in the hue. The image forming apparatus according to the present invention and having: a transfer-medium holding member having a transfer film for adsorbing and carrying a transfer medium and arranged such that an image is formed on the transfer medium; an internally and upwardly pushing member movably disposed on the surface of the transfer film opposite to the surface to which the transfer medium is adsorbed; a moving device for moving the internally and upwardly pushing member by a predetermined quantity so that the internally and upwardly pushing member upwardly pushes the transfer film to deform the transfer film to separate the transfer medium from the transfer film; and a preventing device for preventing vibration of the internally and upwardly pushing member.

Abstract: In an image forming apparatus wherein plural developing devices 3 have alternating electric field applying mechanisms 4, the alternating electric field applying mechanisms 4 have alternating electric field changing mechanisms 7 for reducing the degree of the action of the alternating electric field on at least one of the developing devices 3 which are later in development order, to a level which is lower than that in the preceding step. As required, at least one of the transferring devices 5 which are later in transfer order has a transfer force changing mechanism 8 for increasing the force of transfer to a transfer medium 6 applied to a color-component toner image on an image carrier 1, to a level which is higher than that in the preceding step. Furthermore, an operation condition judging mechanism 9 may judge whether preset transfer failure conditions are satisfied or not, or environmental conditions may be considered by an environmental condition adjusting device 10.

Abstract: A transfer device includes a photosensitive drum on the outer surface of which an image to be transferred is formed; a transfer drum arranged in parallel to the photosensitive drum and substantially in contact with the outer surface of the photosensitive drum, the transfer drum capable of adsorbing a sheet on its outer surface; and a sheet guide for guiding the sheet supplied toward the transfer drum to a transfer position between the photosensitive drum and the transfer drum. At an end of the sheet guide on the side of the transfer position, a hill-shaped guide is provided which flexes at a flexing point in a plane orthogonal to the rotary axis of each of both drums so as to be convex toward the photosensitive drum. The side of the hill-shaped guide from the flexing point toward, and closest to, the transfer position is inclined toward the photosensitive drum with respect to a tangent of the photosensitive drum passing the transfer position.

Abstract: An image forming apparatus includes an image carrying body on which a toner image is created. A sheet carrying/transporting rotational body adsorbs a recording sheet to which the toner image on the image carrying body is transferred, and transports the sheet. The recording sheet is detached after transfer from the sheet carrying/transporting rotating body, and an assisting device thrusts against the non-image area of the recording sheet to limit its detachment from the sheet carrying/transporting rotating body. The image forming device can prevent transportation failure and image smudging that is otherwise generated when a thick sheet provided with a curl before it is adsorbed to a sheet carrying/transporting rotational body is detached in the curved state from the rotational body and transported to a fusing means.

Abstract: A developing device which develops an electrostatic latent image formed on an image carrier by toner, thereby forming a toner image; a transferring device which transfers the toner image to a fed transfer material; a registration device which provides a timing of feeding the transfer material; a curling device which nips the transfer material so as to produce a curl which is curved in the same direction as the transferring device; a curling control device which controls a nip operation mechanism of the curling device; and mode setting means for instructing the curling control device to operate are disclosed. In accordance with a thick sheet mode set in the mode setting means, the nip operation of the curling device is executed and a dummy transfer period in which the transfer operation of the transferring device is stopped is set.

Abstract: An image forming apparatus includes a control unit for forming an adsorb-charging region having a length along a paper transporting direction from a rear end of an image region on the recording paper adsorbed on the recording paper carrying/transporting member toward a backward direction by controlling operation-OFF timing of the adsorb-transferring charging means in such a manner that this operation-OFF timing is delayed from operation-OFF timing of the latent image forming unit, and this length of the adsorb-charging region becomes longer than, or equal to 1.5 mm.

Abstract: An image forming apparatus capable of preventing a transfer material detecting unit from making any detection error when the surface of a transfer drum becomes opaque, and restraining transfer film replacement intervals from being shortened with a simple constitution. The image forming apparatus is provided with a transfer material detecting unit for detecting conditions in which a transfer material is conveyed on a transfer material carrier, and a transfer material peeling unit for peeling the transfer material off the transfer material carrier by contacting the surface of the transfer material carrier. At least part of the transfer material peeling unit is disposed so that it at least linearly contacts the axial surface of the transfer material carrier at the same position as that of the transfer material detecting unit in the axial direction of the transfer material carrier.

Abstract: A predetermined sheet retaining plane C for absorbing a record sheet is provided in the circumferential surface of a sheet carrier, and a low-reflectivity area which is to be partially covered with the record sheet is provided at a leading portion of the sheet retaining plane C. Reflection photosensors for detecting the reflectivity of the sheet carrier including the low-reflectivity area are disposed around the sheet carrier. Whether a record sheet is held in the sheet retaining plane C is judged on the basis of detection signals of the photosensors.

Abstract: An image forming apparatus wherein a plurality of toner images having different colors from each other are successively formed on an image carrier, and the plurality of toner images formed on the image carrier are transferred to a transfer member carried on a transfer member carrier in such a condition that the plural toner images are successively overlapped with each other to thereby form an image, characterized in that the image forming apparatus comprises a pawl-shaped stripping member for stripping the transfer member from the transfer member carrier while being made in contact with a surface of the transfer member carrier at a predetermined timing; a volume electric resistance value of at least a portion of the pawl-shaped stripping member, which is made in contact with the transfer member, is selected to be greater than, or equal to 10 .OMEGA..cm, and smaller than, or equal to 10.sup.7 .OMEGA..cm; otherwise a surface electric resistance value thereof is selected to be greater than, or equal to 10 .

Abstract: An image forming apparatus which prevents the toner image, which is transferred onto the recording sheet but not yet fixed thereto, from being scattered, by reducing the amount of the charge, which is generated by the pre-cleaning charge removal means and attaches to a recording sheet on a transfer-member supporting member after it passes the image transfer stage. In the image forming apparatus, a recording sheet is transported in a state that it is electrostatically attracted onto a drum sheet, a toner image is formed on a photoreceptor drum in accordance with image information, and the toner image is transferred from the photoreceptor drum onto the recording sheet by using a transfer corotron disposed on the rear side of the drum sheet.

Abstract: A rear end plate having openings is bonded to a rear end portion of a transfer film through urethane sponge. To attach the rear end portion of the transfer film to a coupling member of a frame of a transfer material carrying body, restricting portions of respective restricting members are fixed to the coupling member through the respective openings of the rear end plate. The restricting portions of the restricting members abut the top face of the rear end plate so as to restrict a radial movement of the rear end plate and allow its circumferential movement.

Abstract: In a recording sheet conveying device comprising: a dielectric sheet which moves at a predetermined speed while electrostatically retaining a recording sheet on the outer surface thereof; a charger positioned on the side of the inner surface of the dielectric sheet, to induce electrostatic attraction forces between the dielectric sheet and the recording sheet; and a deflector roll having an electrically conductive layer as an outer surface thereof, the deflector roll being confronted with the charger and adapted to push the recording sheet against the dielectric sheet, the number of electric charges provided by the charger is so adjusted that electrostatic attraction forces acting on the rear end portion of the recording sheet are weaker than those acting on the front end portion of the recording sheet, whereby the recording sheet is prevented from being wrinkled when electrostatically retained on the dielectric sheet.

Abstract: A developing method comprising disposing an electrostatic latent image holding body and a development electrode carrying a toner layer opposite to each other with a gap therebetween and transferring the toner from the development electrode to the electrostatic latent image holding body across the gap to develop the electrostatic latent image. A toner carrying layer of a resistive material having the specific resistance of 10.sup.6 to 10.sup.12 .OMEGA..cm is formed over the development electrode opposite to the electrostatic latent image holding body and a fringing field is formed in part of the electrostatic latent image holding body corresponding to the latent image formed over the electrostatic latent image holding body by applying a high-frequency alternating electric field to the development electrode and thereby causing the toner adhere to the electrostatic latent image holding body in the form of the electrostatic latent image.