Patent application number | Description | Published |
20080219712 | Developing device and image forming apparatus - An image forming apparatus provided with an image carrying member to carry an electrostatic latent image, a toner carrying member to develop the electrostatic latent image on the image carrying member with toner; a first developer carrying member to carry developer containing toner, carrier, reverse polarity particles and to supply toner to the toner carrying member; and a second developer carrying member to carry developer and to recover toner on the toner carrying member, wherein an ability to move the reverse polarity particles from the toner carrying member to the first developer carrying member is larger than an ability to move the reverse polarity particles from the second developer carrying member to the toner carrying member. | 09-11-2008 |
20090067890 | Image forming apparatus - Provided are a developing device and an image forming apparatus, the developing device which employs a two-component developer wherein development hysteresis (ghost) is reduced and deterioration of a carrier is stably suppressed, and high-quality images are thus realized for a long period of time. The developing device, which uses a developer including toner, carrier and reverse polarity particles which are charged to have a polarity reverse to that of the toner, performs a collecting operation for collecting the reverse polarity particles at a timing in which image formation is not affected by a collecting operation, where the reverse polarity particles are accumulated in the area enclosed by a toner carrying member, a developer carrying member for toner supply and developer carrying member for collecting toner are collected into a developer container. | 03-12-2009 |
20090252513 | Developing device and image forming apparatus - A developing device and image forming apparatus are provided, wherein high quality images, in which generation of development hysteresis (ghost image) is alleviated, are obtained over a long period using a hybrid development method comprising a toner-supplying developer supporting member and a toner-collecting developer supporting member. Bias voltage is applied in the direction in which the toner is supplied to the toner supporting member in the toner supply region and the toner collection region of the toner-supplying developer supporting member and the toner-collecting developer supporting member respectively so that the toner collecting capability in the toner collection region is higher than the toner collecting capability in the toner supply region. | 10-08-2009 |
20100143002 | Development device and image forming apparatus using the same - In a hybrid development method using a plurality of toner carriers, a development device and image forming apparatus are provided, wherein high image quality in which toner density is not reduced even in the case of high speed printing and the occurrence of development hysteresis (ghost) is controlled is ensured by accelerating the collection of the post-development residual toner on the toner carrier. The counter-charge having occurred in the developer remains in the developer without decreasing to disappear until the developer moves to the second toner carrier on the downstream-side, wherein this counter-charge is caused by supplying toner to the first toner carrier upstream in the rotating direction of the developer carrier. | 06-10-2010 |
20100183343 | DEVELOPMENT DEVICE AND IMAGE FORMING APPARATUS - Provided is a development device and an image forming apparatus that realize high image quality with improved decrease in density at high speed development and with reduced occurrence of development hysteresis (ghost) in the hybrid developing method having a plurality of toner carriers, by reducing the decrease in the toner supplying ability to the downstream-side toner carrier, which decrease is caused by the supply of toner to the toner carrier on the upstream side in the rotating direction of the developer carrier. By providing a magnetic pole between main magnetic poles, of the developer carrier, facing the toner carriers, a magnetically raised bristle of developer is moved by a magnetic force, while the developer in which development hysteresis due to supplying toner to the upstream-side toner carrier occurred is conveyed to supply toner to the downstream-side toner carrier, whereby the developer layer is stirred. | 07-22-2010 |
20100232841 | Method for Developing an Electrostatic Latent Image - The purpose is to provide, in a development apparatus using a two-component developer, a compact development apparatus, image forming apparatus and development method that prevents carrier deterioration and that can carry out good image formation over a long time period. In a development apparatus using a developer in which are mixed a toner, a carrier, and opposite polarity particles that are charged to a polarity opposite to the charging polarity of the toner, the surface charge density of the opposite polarity particles should be in the range of 0.5 to 3.0 times the surface charge density of the carrier. | 09-16-2010 |
20100254725 | DEVELOPMENT APPARATUS AND IMAGE FORMING APPARATUS - Provided are a development apparatus and an image forming apparatus which, in a hybrid development apparatus provided with a plurality of toner carriers, a toner supply capability to supply toner to each toner carrier is controlled independent of development electric fields between the toner carriers and an image carrier, whereby each toner carrier is allowed to exhibit a desired development capability, and even in the case of high speed development, a high quality image is provided. The phases, the frequencies, and/or the duty ratios of the alternating current components of the voltages applied to the plurality of the toner carriers are made to be different, whereby the toner supply amount for each toner carrier from the developer carrier is controlled independently of the development electric fields between the toner carriers and the image carrier. | 10-07-2010 |
20100290820 | DEVELOPMENT DEVICE AND IMAGE FORMING APPARATUS USING THE SAME - Provided is a development device and an image forming apparatus both using a hybrid development method and capable of forming high quality images without occurrence of development hysteresis (ghost). The nip portion of the toner carrier and the developer carrier is configured as follows: the rotating direction of a toner carrier and a developer carrier are in counter directions; a magnetic pole facing the toner carrier is positioned on the upstream side in the developer carrier rotating direction; and a counter charge generated by the toner supply reaches a toner recovering portion without being considerably attenuated. | 11-18-2010 |
20110091248 | IMAGE FORMING APPARATUS - An image forming apparatus provided with a hybrid development apparatus having a plurality of toner carriers, the image forming apparatus having the following constitution: a magnet roller incorporated in a developer carrier is rotated and adjusted and fixed at an appropriate magnetic pole position with respect to one toner carrier; the other toner carrier is moved around the magnet roller shaft having a certain gap therebetween and adjusted and fixed at an appropriate magnetic pole position; and gap members are provided on each toner carrier, and the gap members are brought into contact with an image carrier by a guide member and an bias member provided on the image forming apparatus, thereby maintaining a specific development gap. | 04-21-2011 |
20110116816 | DEVELOPMENT APPARATUS AND IMAGE FORMING APPARATUS USING THE SAME - A development apparatus and an image forming apparatus wherein optical high-precision detection of the toner amount of a toner layer formed on a toner carrying member is ensured even when the great amount of the toner is deposited on the toner carrying member by transferring all or a part of the toner on the surface of the toner carrying member onto a detecting roller, and wherein stable images are provided at all times. | 05-19-2011 |
20110222884 | DEPOSITED TONER MEASURING APPARATUS, IMAGE FORMATION APPARATUS, AND METHOD FOR CONTROLLING IMAGE FORMATION APPARATUS - Provided is a deposited-toner measuring apparatus capable of accurate detection of the amount of toner deposited on the toner carrying member, and an image forming apparatus equipped with the aforementioned measuring apparatus and capable of controlling the amount of toner deposited on the toner carrying member to a desired level so as to provide stable image quality at all times. A deposited-toner measuring apparatus that removes a toner layer in a part of the surface of the toner carrying member, detects change in the capacitance at the portion with a toner layer and the portion without such a toner layer, and detects the amount of the deposited toner based on the detection result of the said change in the capacitance. | 09-15-2011 |
20120237264 | Wet-Type Image Forming Apparatus - An infiltration amount measuring unit is provided to measure the amount of carrier liquid infiltrated in recording paper. An output signal of the infiltration amount measuring unit is input to a control device to be used to calculate a voltage supplied to a heat source (heater) in a pre-fixing unit. A signal of a paper temperature measuring unit is input to the control device, which determines whether a target temperature is reached. The control device estimates the amount of carrier liquid in a toner layer based on the information from the infiltration amount measuring unit. Then, the pre-fixing unit is controlled such that the amount of carrier liquid in the toner layer falls within an appropriate range, based on the estimation result of the amount of carrier liquid. | 09-20-2012 |
20120237265 | Wet-Type Image Forming Apparatus - A wet-type image forming apparatus includes: a heating unit configured to heat a recording medium and to volatilize liquid carrier in a toner image; a fixing unit configured to fix the toner image on the recording medium and disposed at a downstream side of the heating unit in a conveyance direction of the recording medium; a conveyance unit configured to convey the recording medium from the heating unit to the fixing unit; and a housing disposed to cover the conveyance unit, wherein the recording medium is conveyed on the conveyance unit in the housing toward the fixing unit after heated by the heating unit, in the presence of gas containing the volatilized liquid carrier, and the volatilized liquid carrier is cooled and turned into fine mist liquid carrier and then the fine mist liquid carrier attaches to the recording medium before the recording medium reaches the fixing unit. | 09-20-2012 |