Patent application number | Description | Published |
20090060534 | DEVELOPING DEVICE AND IMAGE FORMING APPARATUS - A developing device has stirring members for conveying and stirring a developer-tank-contained developer and a developer holder, and has a developer replenishing tank for replenishing a replenishment developer to a developer tank; a toner concentration detecting sensor; a discharging mechanism for discharging an excessive amount of the developer-tank-contained developer outside the developer tank when the amount of the developer-tank-contained developer inside the developer tank exceeds a predetermined amount; and a control unit for replenishing the developer-tank-contained developer when it is detected that the toner concentration inside the developer tank is lower than a first reference value and for forcibly consuming the toner inside the developer tank and replenishing the replenishment developer when it is detected that the toner concentration inside the developer tank is higher than a second reference value that is higher than the first reference value. | 03-05-2009 |
20090214232 | DEVELOPING DEVICE AND IMAGE FORMING APPARATUS - The present invention provides a developing device and an image forming apparatus capable of carrying out excellent image formation for a long period by making the fluctuations in the toner concentration and the volume level of the developer inside a trickle developing device that uses a two-component developer as small as possible. The developing device having stirring members for conveying and stirring a developer-tank-contained developer and a developer holder, comprises a developer replenishing tank for replenishing a replenishment developer to a developer tank; a toner concentration detecting sensor; a discharging mechanism for discharging an excessive amount of the developer-tank-contained developer outside the developer tank when the amount of the developer-tank-contained developer inside the developer tank exceeds a predetermined amount; and control unit having memory means for storing the current toner concentration inside the developer tank, the reference toner concentration inside the developer tank, a corrected reference toner concentration calculated according to the formula of (the current toner concentration—a correction value), a predetermined replenishment amount to the developer tank and an allowable value for the current toner concentration with respect to the reference toner concentration, and computing means for calculating the corrected reference toner concentration and comparing the current toner concentration with the reference toner concentration and the corrected reference toner concentration. | 08-27-2009 |
20090214233 | DEVELOPING DEVICE AND IMAGE FORMING APPARATUS - The present invention provides a developing device and an image forming apparatus capable of carrying out excellent image formation for a long period by making the fluctuations in the toner concentration and the volume level of the developer inside a trickle developing device that uses a two-component developer as small as possible. The developing device having stirring members for conveying and stirring a developer-tank-contained developer and a developer holder, comprises a developer replenishing tank; a toner concentration detecting sensor; a trickle discharging mechanism; developer amount detecting means; and control unit for controlling the replenishment operation of replenishment toner and carrier at the time when the toner concentration is lower than a predetermined reference toner concentration, wherein the control unit carries out forced consumption operation for the toner inside the developer tank and replenishment operation for the replenishment toner and carrier in the case that the amount of the developer-tank-contained developer inside the developer tank is judged to be low using the developer amount detecting means. | 08-27-2009 |
20090214266 | DEVELOPING DEVICE AND IMAGE FORMING APPARATUS - The present invention provides a developing device and an image forming apparatus capable of preventing a developer from being discharged excessively using simple configurations in the case that a trickle developing device that uses a two-component developer is in a tilted state. The developing device having stirring members for conveying and stirring a developer and a developer holder, comprises a developer replenishing tank for replenishing the developer to a developer tank and a trickle discharging mechanism, wherein the conveying passages thereof include an upper conveying passage, a lower conveying passage, a first communicating passage for connecting the downstream side of the upper conveying passage to the upstream side of the lower conveying passage, and a second communicating passage for connecting the downstream side of the lower conveying passage to the upstream side of the upper conveying passage, and also include a circulation passage through which the developer circulates using the upper conveying passage, the first communicating passage, the lower conveying passage and the second communicating passage; the discharging mechanism is disposed in the downstream end section of the upper conveying passage; the bottom face on the downstream side of the upper conveying passage is positioned above the bottom face on the upstream side of the lower conveying passage; and the first communicating passage is disposed obliquely downward with respect to the horizontal plane. | 08-27-2009 |
20090245879 | DEVELOPING DEVICE, IMAGE FORMING APPARATUS AND METHOD FOR FILLING DEVELOPER - In a trickle developing device that uses a two-component developer, a simple configuration is adopted to prevent carrier from being discharged without being used. The developing device having stirring members for conveying and stirring developer and a developer holder, comprises a developer replenishing tank for replenishing developer to a developer tank and a trickle discharging mechanism, wherein the initial filling amount of the developer-tank-contained developer to be filled initially into the developer tank is less than a full filling amount. | 10-01-2009 |
20090290886 | DEVELOPING APPARATUS AND IMAGE FORMING MACHINE - In the case that images having high coverage ratios are printed out continuously in a trickle developing apparatus that uses a two-component developer, the developing apparatus judges how much carrier is accumulated inside a developer tank beyond the discharge level of a trickle discharging mechanism and carries out appropriate processing before the developer overflows over a regulating gap. The developing apparatus, having stirring members for conveying and stirring a developer-tank-contained developer and a developer holder, comprises a developer replenishing tank; a discharging mechanism for discharging an excessive amount of the developer-tank-contained developer outside the developer tank when the amount of the developer-tank-contained developer inside the developer tank has exceeded a predetermined amount; and calculating device for calculating the amount of the carrier existing inside the developer tank, and carries out predetermined danger avoiding operation when it has been judged using the calculating device that the integrated value of carrier obtained by integrating the amount of the carrier existing inside the developer tank is likely to exceed a predetermined excessive accommodation amount of carrier. | 11-26-2009 |
20090290887 | DEVELOPING APPARATUS AND IMAGE FORMING MACHINE - The present invention provides a developing apparatus capable of predicting how much carrier is accumulated inside a developer tank beyond the discharge level of a trickle discharging mechanism in the case that images having high coverage ratios are printed out continuously in a trickle developing apparatus that uses a two-component developer. The developing apparatus, having stirring members for conveying and stirring a developer-tank-contained developer and a developer holder, comprises a developer replenishing tank; a discharging mechanism for discharging an excessive amount of the developer-tank-contained developer outside the developer tank when the amount of the developer-tank-contained developer inside the developer tank has exceeded a predetermined amount; and calculating device for calculating the amount of the carrier existing inside the developer tank, and judges using the calculating device that the integrated value of carrier obtained by integrating the amount of the carrier existing inside the developer tank is likely to exceed a predetermined excessive accommodation amount of carrier. | 11-26-2009 |
20090304415 | DEVELOPING DEVICE AND IMAGE FORMING APPARATUS - A developing device includes a housing in which nonmagnetic one-component toner is housed, a developing roller which horizontally extends in an opening of the housing, and a feed roller which is set in the housing in pressure contact with the developing roller so as to form a nip portion and which feeds toner to the developing roller. The developing device also includes a feed stabilizing member which is in contact with a lower portion of the feed roller so as to form a second nip portion, and which restricts toner feed quantity. The feed stabilizing member is provided so as to extend from a generally triangular-shaped first region below the first nip portion up to one side of the nip portion opposite to the first region side. The developing device further includes a toner circulation path for pushing back toner from the first region through below the feed stabilizing member to a second region on the one side opposite to the first region side with an aid of pressure of toner that tends to accumulate in the first region. | 12-10-2009 |
20100322671 | DEVELOPING APPARATUS AND IMAGE FORMING APPARATUS PROVIDED WITH THE SAME - A housing of a developing apparatus is provided with a conveying member in a developer supplying and recovering portion, and with two agitating members rotating from the below to the above in portions opposed to each other in a developer agitating portion. A guide is provided in an inner bottom surface of the housing between two agitating members. A braking portion suppressing a discharge of a developer is provided in a downstream side of the developer agitating portion in a developer conveying direction of the second agitating member, and a discharge portion is provided in a downstream side of a disc of the braking portion. | 12-23-2010 |
20100322672 | DEVELOPING APPARATUS AND IMAGE FORMING APPARATUS PROVIDED WITH THE SAME - A housing of a developing apparatus is provided with a conveying member and two agitating members. A guide is provided in an inner bottom surface of the housing between two agitating members. A guide is formed into a mountain shape with wide foot portion in a cross sectional shape which is orthogonal to an axial direction of rotating shafts of the agitating members. The guide is arranged in such a manner that a gap between respective outermost portions of two agitating members, and an inner bottom surface of the housing and the guide becomes equal to or more than 1.5 mm and less than 3 mm. Further, each of two agitating members rotates in a direction from the below to the above at a position of the guide. | 12-23-2010 |
20100322673 | DEVELOPING APPARATUS AND IMAGE FORMING APPARATUS PROVIDED WITH THE SAME - A housing of a developing apparatus is provided with a conveying member in a developer supplying and recovering portion, and with two agitating members rotating from the below to the above in portions opposed to each other in a developer agitating portion. A guide is provided in an inner bottom surface of the housing between two agitating members. A discharge portion provided with a developer discharge port is provided on a downstream side of the developer agitating portion in a developer conveying direction of the first agitating member. A suitable amount of developer can be circulated while conveying a part of an excess amount of developer in a circulating conveying path to the discharge portion and discharging from the developer discharge port. Packing and leaking of the developer within the developing apparatus and breakage of the developing apparatus can be prevented and also a good image can be obtained even if high printing images are continuously provided. | 12-23-2010 |
20100322674 | DEVELOPING APPARATUS AND IMAGE FORMING APPARATUS PROVIDED WITH THE SAME - A housing of a developing apparatus is provided with a conveying member in a developer supplying and recovering portion, and two agitating members rotating in the same direction respectively as viewing rotating shafts from a near side in an axial direction, in a developer agitating portion. A guide is provided in an inner bottom surface of the housing between two agitating members. A braking portion suppressing a discharge of a developer is provided in a downstream side of the developer agitating portion in a developer conveying direction of the first agitating member, and a discharge portion is provided in a downstream side of a disc of the braking portion. | 12-23-2010 |
20100322675 | DEVELOPING APPARATUS AND IMAGE FORMING APPARATUS PROVIDED WITH THE SAME - A housing of a developing apparatus is provided with a conveying member and two agitating members. A guide is provided in an inner bottom surface of the housing between the agitating members. The guide has a mountain shape with wide foot portion in a cross sectional shape which is orthogonal to an axial direction of rotating shafts of the agitating members. The agitating members are arranged in such a manner that gaps between respective outermost portions thereof and the inner bottom surface of the housing and the guide become equal to or more than 1.5 mm and less than 3 mm. The agitating members rotate from the below to the above in a portion in which they are opposed to each other. A discharge portion is provided on a downstream side of a developer agitating portion in a developer conveying direction of the first and second agitating members. | 12-23-2010 |
20110150533 | DEVELOPING APPARATUS AND IMAGE FORMING APPARATUS PROVIDED WITH THE SAME - A housing of a developing apparatus is provided with a conveying member in a developer supplying and recovering portion, and two agitating members rotating in the same direction respectively as viewing rotating shafts from a near side in an axial direction, in a developer agitating portion. A guide is provided in an inner bottom surface of the housing between two agitating members. A braking portion suppressing a discharge of a developer is provided in a downstream side of the developer agitating portion in a developer conveying direction of the second agitating member, and a discharge portion is provided in a downstream side of a disc of the braking portion. | 06-23-2011 |
20110150535 | DEVELOPING APPARATUS AND IMAGE FORMING APPARATUS PROVIDED WITH THE SAME - A housing of a developing apparatus is provided with a conveying member and two agitating members. A guide is provided in an inner bottom surface of the housing between the agitating members. The guide has a mountain shape with wide foot portion in a cross sectional shape which is orthogonal to an axial direction of rotating shafts of the agitating members. The agitating members are arranged in such a manner that gaps between respective outermost portions thereof and the inner bottom surface of the housing and the guide become equal to or more than 1.5 mm and less than 3 mm. The agitating members rotate in the same direction respectively as viewing the rotating shafts from a near side in an axial direction. A discharge portion is provided on a downstream side of the developer agitating portion in a developer conveying direction of the first and second agitating members. | 06-23-2011 |
20120321355 | DEVELOPMENT DEVICE - A development device having: a main unit having formed therein a first space and a second space extending in a first direction perpendicular to a vertical direction, a first communicating portion and a second communicating portion that allow the first space and the second space to communicate with each other at both ends in the first direction; a first stirring member that extends in the first direction within the first space; a second stirring member that is positioned within the first space between the first stirring member and the second space and extends in the first direction; a conveyance member that extends in the first direction within the second space; and a developer support member that extends in the first direction within the second space. | 12-20-2012 |