Konica Minolta Business Technologies, Inc.

Konica Minolta, Inc.

Junji Murauchi

Tetsuya Kagawa

Hiroaki Takada

Megumi Minami

Kazuhiro Saito

Chikara Tsutsui

Tomohiro Kato

Takuya Okada

Yoshiki Nakane

Morio Osada

Hiroshi Goto

Noritoshi Hagimoto

Ken Nakano

Tomohisa Yoshida

Tomoyuki Imura

Masanori Kawada

Kazuki Kobori

Tomo Kitada

Takuya Sasaki

Eri Yoshida

Hokuto Hatano

Tetsuo Sano

An electrophotographic image forming apparatus includes: a replacement detector that detects that a toner bottle has been replaced; a developer that develops an electrostatic latent image by using a toner supplied from the toner bottle and stored; a fog detector that detects a fog amount; and a determiner that determines whether or not the detected fog amount continuously exceeds a predetermined threshold value in a state where a toner supplied from a toner bottle before replacement and a toner supplied from a toner bottle after replacement are mixed in the developer.

Image forming apparatus and determination method

An elastic member that comes into contact with a moving body that moves in a predetermined moving direction to scrape off a deposit on the moving body includes: a stress reducer that is provided at a contact end on a side to be in contact with the moving body and reduces vibration of internal stress generated due to contact between the moving body and the elastic member, wherein the stress reducer extends in a direction that is not perpendicular to the moving direction when the elastic member comes in contact with the moving body.

Elastic member, cleaning device, and image forming apparatus

A cleaning device scrapes off and removes toner that has adhered to a surface of a rotating photoreceptor, and includes: a cleaning member formed of an elastic body; a leaf spring member for pressing the cleaning member against the surface of the photoreceptor; and a support portion supporting the leaf spring member. The cleaning member is fixed to one end of the leaf spring member, and the other end of the leaf spring member is fixed to the support portion with a cushioning member formed of an elastic body interposed therebetween. The cushioning member is fixed to the other end of the leaf spring member by an adhesive.

Cleaning device and image forming apparatus including the same

A photo conductor cleaning device removes substances adhered to a surface of a photo conductor which moves around the axis of rotation. The photo conductor cleaning device is equipped with a device main body, a tip blade, and a flexible supporting sheet metal plate which holds the tip blade and makes the tip blade contact with the photo conductor. The supporting sheet metal plate is fixed to the device main body by two fixing portions which are places at different locations, as seen from a cross section perpendicular to the axis of rotation of the photo conductor. The supporting sheet metal plate is supported at the both ends by the two fixing portions support.

Cleaning device which removes adhered substances on image supporting body

A power supply applies a first charged voltage to a charging section disposed near an image carrier during a predetermined process and applies second charged voltages sequentially to the charging section in obtaining a predetermined peak-to-peak voltage value for an alternating-current voltage of the first charged voltage. Each of the second charged voltages includes an alternating-current voltage having a peak-to-peak voltage value varying between a forward discharge range and a back discharge range. A current sensing section senses the alternating-current running through the charging section upon application of each of the second charged voltages. A control section derives a first approximation function and a second approximation function on the basis of the alternating-current values sensed by the current sensing section and sets a peak-to-peak voltage value as the predetermined peak-to-peak voltage through a difference function representing a difference value between the first approximation function and the second approximation function.

Image forming apparatus with a power supply applying charged voltage to a charging section

An image forming apparatus includes photoconductors. Electrifiers uniformly electrify surfaces of the photoconductors. A power source applies an electrifying voltage to the electrifiers. A current measurer measures alternating current caused to flow by application of AC voltage by the power source. A controller calculates discharge starting voltage. Environment detectors detect an environment inside of the apparatus. The controller operates the current measurer at each predetermined timing to acquire the discharge starting voltage. When acquiring the discharge starting voltage, the controller changes peak-to-peak voltage at pre-discharge voltage and at post-discharge voltage. The current measurer measures alternating current at measurement points of each of the pre-discharge and post-discharge voltages. The controller calculates a voltage value at an intersection of a first line and a second line. After acquiring the discharge starting voltage, the controller calculates environment-correction discharge starting voltage, and sets electrification voltage based on the calculated voltage.

Image forming apparatus for setting an electrification voltage

An image forming apparatus includes a photoreceptor rotatable about an axis, and having a surface with a photosensitive layer abraded during use, a charging unit configured to charge the surface of the photoreceptor, an exposure unit configured to form an electrostatic latent image on the surface of the photoreceptor, a developing unit configured to form a toner image on the surface of the photoreceptor, and a control unit configured to obtain a film thickness of the photosensitive layer for each of a plurality of different positions in a direction of a rotation axis of the photoreceptor, and perform abrasion operation at a first or second position of the plurality of positions, when a difference in film thickness between the first position and the second position exceeds a predetermined reference value.

Image forming apparatus

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.

Development device

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.

Developing apparatus and image forming machine

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.

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.

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.

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.

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.

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.

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Toyokawa, Japan

Junji Murauchi