Ricoh Company, Ltd.

Natsumi Matsue

Junichi Matsumoto

Hiroshi Kikuchi

Takashi Hashimoto

Akira Yoshida

Kayoko Tanaka

Hideo Yoshizawa

Tetsuo Watanabe

Takeshi Ogawa

Tomoya Ohmura

Yasuo Takuma

Kohta Fujimori

Yuuichiroh Uematsu

Koichi Kudo

Akio Kosuge

Fumihito Masubuchi

Jun Shiori

Keiko Matsumoto

Shingo Kuboki

Yoichi Sakurai

Daisuke Hamada

Kazuaki Kamihara

Yoshinobu Takeyama

Kohei Matsumoto

Keita Sone

Taku Kumiya

Kazufumi Kimura

An image forming apparatus includes an image forming device, an image density detector, and a processor. The processor controls the image forming device to form a first test toner image, and controls the image density detector to detect an image density at the plurality of positions of the first test toner image. The processor adjusts an image forming condition so that the image density detected at each of the plurality of positions becomes a target image density, controls the image forming device to form a second test toner image based on the adjusted image forming condition, controls the image density detector to detect an image density at the plurality of positions of the second test toner image, determines whether a streak exists in the second test toner image based on the detected image densities, and executes a countermeasure to prevent an occurrence of the streak.

Image forming apparatus and image forming method

A powder container for an image forming apparatus includes: a rotatable powder storage storing powder; an opening on one end of the powder storage, through which a nozzle can be inserted; and a scooping portion to scoop up powder on an opening side, and supply the powder to a powder receiving hole of the nozzle when the powder storage rotates. The scooping portion includes a scooping surface extending inwardly from an inner wall surface of the powder storage and an inner end portion extending in a rotation axis direction of the powder storage, with an edge approximately parallel to the rotation axis. In a cross-section perpendicular to the rotation axis, the scooping surface is inclined toward an upstream side in a rotation direction of the powder storage with respect to a virtual line that passes through the rotation axis and is tangent to the edge of the inner end portion.

Powder container and image forming apparatus

An image forming apparatus includes a rotatable image bearer, a toner image forming device, an image reader, and a control unit. The toner image forming device forms a test toner image on the image bearer. The image reader reads the test toner image and a predetermined reference member. The control unit calculates an amount of toner contained in the test toner image based on image data from the test toner image. Based on image data from the reference member, the control unit selects a position of a pixel to be used for calculation of the amount of toner contained in the test toner image from pixels included in the image data from the reference member, to calculate the amount of toner contained in the test toner image from data of a pixel located at the position thus selected among pixels included in the image data from the test toner image.

Image forming apparatus incorporating image reader

An image forming apparatus includes an image bearer, an image forming device to form a toner image on the image bearer, a transfer device to transfer the toner image to a recording medium, a line sensor as an image density sensor to detect image density of the toner image, and a controller operatively connected to the image density sensor. The image density sensor is disposed so as to be shorter in a rotational direction of the image bearer than in a width direction of the image bearer perpendicular to the rotational direction of the image bearer. The controller forms a shading pattern image including a plurality of patches on the image bearer, and detects image density of the plurality of patches, so as to control image density. The shading pattern image is shorter in the rotational direction of the image bearer than in the width direction of the image bearer.

Image forming apparatus incorporating line sensor

An image forming apparatus includes an image bearer that bears a toner image, a sensor, an adhesion amount calculator, and a wavelength determiner. The sensor includes a light source that emit light onto the image bearer, and an image element that detects reflected light that is emitted from the light source and reflected from the image bearer. The adhesion amount calculator calculates a toner adhesion amount of the toner image on the image bearer based on the reflected light having at least one wavelength among a plurality of wavelengths detected by the sensor. The wavelength determiner determines, based on color information of the image bearer detected by the sensor, a wavelength to be used in calculation of the toner adhesion amount by the adhesion amount calculator.

Image forming apparatus and control method for image forming apparatus

An image forming apparatus includes a developer bearer and a toner pattern bearer rotatable in a given direction of rotation to bear an adjustment toner pattern formed with the developer bearer. A toner pattern detector detects an amount of reflection light reflected by the adjustment toner pattern on the toner pattern bearer. A controller performs an adjustment mode to convert the detected amount of reflection light into a toner adhesion amount of toner of the adjustment toner pattern adhered to the toner pattern bearer. The controller forms an adhesion amount suppressing toner image on an upstream region on the toner pattern bearer that is upstream from the adjustment toner pattern in the direction of rotation of the toner pattern bearer. The upstream region is defined by a circumferential length of the developer bearer in the direction of rotation of the toner pattern bearer.

A process cartridge is detachably mounted on an apparatus main body of an image forming apparatus. An embodiment of the cartridge includes a developer bearer arranged to be opposed to an image bearer in a developing device and rotates; a positioning member that supports the image bearer and the developer bearer at respective ends thereof, and fixes a distance between rotating shafts of the image bearer and the developer bearer; a rotating shaft arranged on a rotating member arranged on the developing device, and having a part protruding from an outer surface of a housing frame of the process cartridge; a gear that is arranged at a distal end of the rotating shaft and transmits a rotational driving force transmitted from the apparatus main body; and a bearing that is arranged between the positioning member and the gear, is fixed to the housing frame, and supports the rotating shaft.

Process cartridge and image forming apparatus

An image forming apparatus includes an image forming unit to form an adhesive toner pattern in a predetermined bonding range of a sheet, outside a printable range in which an image according to image data is formed, a stacking unit to stack multiple sheets one on top of another, and a sheet binding device that includes a fusing device to fuse and fix the adhesive toner pattern formed on the multiple sheets to bind the multiple sheets together, and a bonding strength setting unit to determine, in accordance with a desired bonding strength, at least one of a number of color toners used for forming the adhesive toner pattern, a bonding manner, a number of pixels of the adhesive toner pattern, a toner area ratio of the adhesive toner pattern, and a layer thickness of the adhesive toner pattern.

Sheet binding device and image forming apparatus incorporating same

A development device having a development portion with a developer spout, to develop a latent image formed on an image carrier with developer including toner and carrier particles. The development unit also includes a circulation unit to convey developer collected from the development portion to the developer spout, a developer container, provided in the circulation unit, to contain the developer at a position upstream from the development portion in a developer circular direction, the developer container having a cylindrical upper portion and a funnel-shaped lower portion continuous with the cylindrical upper portion through a joint so that a level of the developer contained in the developer container at rest is positioned near the joint between the cylindrical upper portion and the funnel-shaped lower portion. An agitator is provided inside the developer container, to agitate and mix the collected developer and fresh toner supplied to the developer container.

Development device and image forming apparatus incorporating same

A bookbinding system includes an image forming unit to form a toner image on a sheet; a fixing device to fix the toner image onto the sheet; a sheet stacker to load sheets passing through the fixing device, to create a sheet bundle, in which the sheet bundle stacked on the sheet stacker is adhered to produce a complete book; an adhesive toner image forming unit to form an adhesive toner image on an area corresponding to a spine of the complete book; and a heater to heat the unfixed adhesive toner image formed on each sheet of the sheet bundle stacked on the sheet stacker, wherein the adhesive toner image on the sheet stacked on the sheet stacker is the unfixed toner image.

Bookbinding system using unfixed toner image as adhesive

In a disclosed developing device, a developing part includes a developer carrier for circulating a developer inside the developing part and for supplying the developer to an image carrier, a developer supply member for supplying the developer to the developer carrier, and a developer collection member for collecting the developer which is not used. A developer stirring part is arranged at a different position from a position of the developing part. A developer conveyance part carries the developer by an air conveyance in a developer conveyance path from the developer stirring part to the developing part. A developer detection part includes an opening which communicates between the developer supply member and the developer collection member, is arranged at a downstream side in a flow direction of the developer below and near the developer supply member, and detects whether the developer exists in a vicinity of the developer supply member.

Developing device and image forming apparatus

A development device includes a development portion, to develop a latent image formed on a latent image carrier with developer, disposed close to the latent image carrier; a developer agitation container to agitate the developer, provided separately from the development portion; a transport system connecting the development portion and the developer agitation container, through which the developer is transported from the developer agitation container to the development portion by air; and a developer retainer to temporarily retain the developer, disposed downstream from the transport system, to which the developer remaining in the transport system escapes.

A developing device in the embodiment includes: a developer carrier that carries a two-component developer, moves the surface, and supplies the toner to a latent image on a surface of a latent image carrier; a first conveying member that conveys the developer in a first conveying path; a second conveying member that conveys the developer in a second conveying path; and a developer passing unit that conveys upward the developer which has reached at a conveying-direction posterior end of the second conveying path and passes the developer to the first conveying path. The developer passing unit includes a plurality of pushing members that push up the developer. The developer can pass through from upper surfaces of the pushing members to lower surfaces of the pushing members.

A developing device includes a developer supply part and a developer collecting part, wherein the developer supply part has a developer inlet port for introducing a developer supplied from a reservoir into the developer supply part and a developer extraction port provided on the side of the developer inlet port to remove a portion of the developer so as to define a quantity of the developer to be introduced in the developer supply part, and wherein the developer extraction port and the developer collecting part are connected to the reservoir.

A development device includes a development portion to develop a latent image formed on a latent image carrying member with developer including toner and carrier particles, a circulation unit to convey the developer collected from the development portion to development portion, the circulation unit including a container to store the developer, disposed upstream from the development portion in a direction in which the developer is circulated, and a first agitator provided inside the container, to agitate and mix the collected developer and fresh toner supplied to the container, the first agitator formed by multiple linear members.

Growing community of inventors

Kanagawa, Japan

Natsumi Matsue