Patent application number | Description | Published |
20080232880 | Sheet conveying device and image forming apparatus - A sheet conveying device includes a pair of upstream rollers and a pair of downstream rollers each including a drive roller and a driven roller, a calculating unit, and a control unit. The upstream rollers include a measuring unit that obtains speed information of the upstream rollers. The calculating unit calculates a target value based on the speed information. The control unit controls the speed of the drive roller of the downstream rollers based on the target value. | 09-25-2008 |
20080303202 | SHEET CONVEYING DEVICE AND IMAGE FORMING APPARATUS - A fluctuation detecting unit detects a fluctuation of an endless belt generated when a sheet is brought into contact with a predetermined position of the endless belt at an upstream side in a conveying direction from a nip portion based on fluctuation information acquired by a fluctuation information acquiring unit. An entry timing estimating unit estimates entry timing of the sheet into the nip portion based on a detection of the fluctuation. A correction control unit corrects a speed fluctuation of the endless belt generated when the sheet enters the nip portion by performing a feedforward control of a first driving unit based on the entry timing. | 12-11-2008 |
20090052912 | ABNORMALITY DETERMINING APPARATUS, IMAGE FORMING APPARATUS, COPYING MACHINE, AND INFORMATION OBTAINING METHOD - A time point at which a predetermined period elapses since the start of use of a copying machine as a detection subject after factory shipment or repair is obtained. Pieces of set information, which are combinations of various types of information until the time point is reached are sequentially stored to construct a normal set information group. After the time point is reached, presence of abnormality in the copying machine is determined based on the normal set information group and the various types of information obtained. | 02-26-2009 |
20090060613 | Image transfer apparatus, image fixing apparatus, and registration apparatus - A load torque variation upon entry or exit of a sheet into a nipping portion is reduced while a nipping force necessary for image formation is provided. An image transfer apparatus, an image fixing apparatus, or a registration apparatus comprises an opposite roller, a transfer roller, and a compression spring for pressing the opposite roller onto the transfer roller. A sheet of transfer material is transported into a nipping portion between the opposite roller and the transfer roller, where an image on the opposite roller is transferred to the transfer material. The apparatus includes a retaining unit configured to retain a certain distance between the first rotating body and the second rotating body as long as the thickness of the transfer material that passes through the nipping portion remains the same. | 03-05-2009 |
20090116860 | Image forming device - An image forming device is disclosed that is able to enlarge a gap of a nipping portion with a simple and inexpensive structure, and able to reduce impact when a front end of a recording sheet runs into or a back end of the recording sheet passes through the nipping portion. The image forming device includes an image carrying unit, an image forming unit, a transfer unit, a conveyance unit, a determination unit that determines whether a thickness of the recording sheet is greater than a threshold value, and a cam member that rotates to enlarge or reduce the gap of the nipping portion between the image carrying unit and the transfer unit according to rotational positions of the cam member. When the thickness of the recording sheet is greater than the threshold, the cam member rotates so that the gap of the nipping portion is enlarged. | 05-07-2009 |
20090162118 | Driving apparatus and image forming apparatus - A driving apparatus includes a driving unit, a driven unit driven by the driving unit, a driving control unit configured to control the driving unit by performing feed-forward control based on feed-forward target data determined in advance to reduce a speed change of the driven unit. The speed change of the driven unit is expressed substantially as a positive half cycle of a sinusoidal waveform having an amplitude and a time duration, and the feed-forward target data is calculated from the amplitude and the time duration to represent a rectangular waveform approximating the positive half cycle of the sinusoidal waveform. | 06-25-2009 |
20090207461 | Image forming apparatus - In an image forming apparatus, a distance adjusting unit adjusts an inter-unit distance between a contact unit and an image carrier by moving the image carrier or the contact unit by applying an opposing force to the image carrier or the contact unit against a biasing force applied by a biasing unit based on thickness information of a recording sheet acquired by a thickness-information acquiring unit and data indicating a relationship between the thickness information and an inter-unit distance change amount stored in a data storage unit. | 08-20-2009 |
20090212488 | Sheet conveying device and image forming apparatus - A sheet conveying device includes a torque estimation unit that, based upon a first load torque generated at a time that a sheet-like member passes through a first nip between a first driving roller and a first driven roller of an upstream sheet conveying unit, estimates a second load torque generated at a time that the sheet-like member passes through a second nip between a second driving roller and a second driven roller of a downstream sheet conveying unit; and a control unit that controls the driving torque such that the second load torque is counterbalanced by applying a counterbalancing torque in synchronization with a timing of entry of the sheet-like member into the second nip. | 08-27-2009 |
20090212491 | Sheet conveying device and image forming apparatus - A second rotary member is arranged opposite to a first rotary member to form a nip between them. A driving unit drives the first rotary member. A sheet-width measuring unit measures a width of a sheet to be fed into the nip. A speed compensating unit compensates a fluctuation of a rotation speed of the first rotary member occurring when the sheet is fed into the nip. The speed compensating unit adjusts a compensation target value for compensating the fluctuation of the rotation speed of the first rotary member based on the width of the sheet measured by the sheet-width measuring unit. | 08-27-2009 |
20090220277 | Image forming apparatus - An image-carrier driving unit drives an image carrier. An image forming unit forms an image on the image carrier. A moving-member driving unit drives a moving member that is movable towards and away from the image carrier. A detecting unit detects a position of the moving member at predetermined sampling times while the moving member is moving. A movement control unit performs a feedback control on the moving-member driving unit such that a detection result of the detecting unit follows a target value corresponding to each of the predetermined sampling times when the moving member moves while the image forming unit is forming the image on the image carrier. | 09-03-2009 |
20100046991 | Image forming apparatus - An image forming apparatus includes an image transfer belt, a first pressure member, a second pressure member, and an adjustable tension member. The image transfer belt is trained around multiple rollers for rotation along an endless belt travel path to convey an image for transfer to a recording sheet. The first pressure member is disposed on an outer surface of the image transfer belt. The second pressure member is disposed on an inner surface of the image transfer belt opposite the first pressure member. The first and second pressure members define an image transfer gap therebetween. The adjustable tension member is disposed on the image transfer belt adjacent the image transfer gap to adjust tension on the image transfer belt when the recording sheet enters and exits the image transfer gap. | 02-25-2010 |
20100054781 | Transfer device and image forming apparatus - A transfer roller lies opposite to a supporting roller across an image carrying belt and abuts against the outer surface of the image carrying belt to form a transfer nip. A driving force transmission unit transmits driving force from a driving source to a driving roller. A drive control unit performs drive control of the driving source. A feedforward control unit performs feedforward control on the driving source via the drive control unit. An entry detecting unit detects entry of a sheet in the transfer nip. The feedforward control unit considers an entry detection signal output by the entry sensor as a trigger for performing feedforward control after a predetermined time. | 03-04-2010 |
20100245460 | Image Forming Apparatus And Foam Application Device - A disclosed image forming apparatus is capable of solving the problems of deterioration of a foam application function and driving systems caused by the dried and fixed foam remaining without being applied. The image forming apparatus includes a foam forming section forming foam, a reservoir section supplying foam formed by the foam forming section to an application roller, a discharge channel through which extra foam is collected from the reservoir section, and a heating unit for heating the extra foam to return the extra foam to a liquid form. The discharged liquid prepared by defoaming the foam discharged through the discharge channel is returned to a container containing the defoamed liquid. | 09-30-2010 |
20120249627 | IMAGE FORMING APPARATUS - An image forming apparatus including an image forming device forming an image on a surface of a recording material; a recording material passage; a treatment liquid applicator including a tray containing a treatment liquid, a first roller applying the treatment liquid to the surface of the recording material, and a second roller drawing the treatment liquid from the tray to supply the treatment liquid to the first roller; a liquid level inclination detector detecting whether the surface of the treatment liquid is inclined; a treatment liquid supplying device supplying the treatment liquid to the tray; and a controller connected with liquid level detector and the treatment liquid supplying device. The controller stops the operation of the treatment liquid supplying device when determining according to the detection result of the liquid level detector that the surface of the treatment liquid is inclined in a predetermined amount or more. | 10-04-2012 |
20120262519 | TREATMENT LIQUID APPLICATION DEVICE AND IMAGE FORMING APPARATUS - A treatment-liquid application device includes a treatment-liquid container, a liquid supply unit, a liquid chamber unit, a treatment-liquid carrier, a transport unit, a treatment-liquid applicator, and a partition. The partition is disposed in an area of the chamber unit defined by an imaginary entry plane, an imaginary exit plane, a carrying surface of the carrier, and a bottom face of the chamber unit. The entry plane includes an entry line at which the carrying surface enters treatment liquid in the chamber unit, and vertically extends from the entry line. The exit plane includes an exit line at which the carrying surface exits from the liquid in the chamber unit, and vertically extends from the exit line. The partition extends in a longitudinal direction of the carrier and has an edge portion adjacent to the carrying surface. | 10-18-2012 |