Canon Kabushiki Kaisha

Ryota Fujioka

Teppei Nagata

Takehiro Kojima

Shota Takami

Kenichiro Kitajima

Yoshiro Tsukada

Takahiro Suzuki

Shuichi Tamura

Naoyuki Yamamoto

Shohei Okumura

Koji Arimura

Tomohito Nakagawa

An image forming system includes an image forming apparatus including an image forming unit and a first control unit which controls the image forming unit, a varnish application apparatus provided downstream in a sheet conveyance direction with respect to the image forming apparatus and including a varnish application unit which applies varnish to a sheet and a second control unit which controls the varnish application unit, and a sheet conveyance apparatus provided between the image forming apparatus and the varnish application apparatus in the sheet conveyance direction and including a receiving roller which receives a sheet discharged from the image forming apparatus, a processing unit which performs predetermined processing on a sheet present in the sheet conveyance apparatus, and a third control unit which controls the processing unit, wherein the first control unit is capable of communicating with the second control unit and the third control unit.

Image forming system

An image forming system includes an image forming apparatus, a varnish application apparatus, and a controller. The varnish application apparatus includes a varnish application unit configured to apply varnish to a recording material, a first conveyance unit configured to convey a recording material in a first conveyance path that passes through the varnish application unit, and a second conveyance unit configured to convey a recording material in a second conveyance path that does not pass through the varnish application unit. When failure is occurred to one or both of the varnish application unit and the first conveyance unit and failure is not occurred to the second conveyance unit, the controller is configured to permit execution of the second image forming job and to convey a recording material by the second conveyance unit in the varnish application apparatus.

An image forming system includes an image forming apparatus, a varnish application apparatus, and a controller. When the image forming apparatus is in a standby state and preheating of varnish in a tank by a heater is completed, if an image forming job of forming a toner image on a first recording material and applying varnish thereto by a varnish coater is received, the controller controls a guide member to guide the first recording material to a first conveyance path. When the image forming apparatus is in a standby state and preheating of varnish in the tank by the heater is not completed, if an image forming job of forming a toner image on a second recording material and not applying varnish thereto by the varnish coater is received, the controller controls the guide member to guide the second recording material to a second conveyance path.

An image forming system includes an image forming unit for forming an image on a recording medium, a varnish applying unit for applying varnish to the image on the recording medium, and a control unit for controlling the image forming unit to form a first image and a second image and for controlling the varnish applying unit to apply varnish to the first image and the second image such that a first varnish application amount applied to the first image by the varnish applying unit is different from a second varnish application amount applied to the second image by the varnish applying unit.

A developing device includes a rotatable developer carrying member carrying a liquid developer on a carrying surface for developing an electrostatic latent image borne on an image bearing member, and an end portion restricting member, provided in contact with the developer carrying member at an end portion of the developer carrying member with respect its rotational axis direction, for restricting movement of the liquid developer in the rotational axis direction of the developer carrying member. A contact angle of the liquid developer to a side surface of the end portion restricting member on a side where the developer carrying member carries the liquid developer is larger than a contact angle of the liquid developer to the carrying surface of the developer carrying member, and the contact angle of the liquid developer to the side surface of the end portion restricting member is 45&#xb0; or more.

Developing device having liquid developer movement restriction

An image forming apparatus includes an outer roller configured to form a contact portion that is in contact with an outer circumferential surface of a belt member, an inner roller configured to abut against the outer roller via the belt member, a first roller adjacent to the outer roller and the inner roller on a downstream side in a direction of movement of the belt member, and a second roller adjacent to the outer roller and the inner roller on an upstream side. At least a portion of at least one of the first and second rollers is provided on a same side as the outer roller with respect to a tangent passing an intersection of the inner roller and a straight line connecting a center of rotation of the outer roller and a center of rotation of the inner roller.

Image forming apparatus with belt cleaning device

An image forming apparatus includes a control unit configured to execute a stop mode in which, after image forming operation is stopped, a developer bearing member is rotated for a predetermined time with a potential difference between a film forming electrode and a developer bearing member set to zero or smaller than that during image formation, and thereafter, the rotation of the developer bearing member is stopped.

Image forming apparatus

A developing apparatus includes a developer bearing member, a developer container, and a storage tank arranged within the developer container to store liquid developer to be supplied to the developer bearing member. The storage tank includes a first bottom surface including an inclined portion that is inclined downward with respect to a horizontal direction in a rotational axis direction of the developer bearing member, and a discharge port arranged on a lower end of the inclined portion of the first bottom surface. The developer container includes a second bottom surface including an inclined portion that is inclined downward with respect to the horizontal direction toward an opposite direction as the inclined portion of the first bottom surface in the rotational axis direction of the developer bearing member, and a discharge port arranged on a lower end of the inclined portion of the second bottom surface.

Developing apparatus

A developer container is capable of supplying a liquid developer to a portion, of a surface of a cleaning roller, between a cleaning position X and a contact position Y with respect to a rotational direction of the cleaning roller. A free end of a cleaning blade is positioned in a range of 65&#xb0; or more and less than 95&#xb0; as a positive angle of the rotational direction of the cleaning roller when a line passing through a center of the cleaning roller and an upper end portion of the cleaning roller with respect to a direction of gravitation is at 0&#xb0; (reference line G). In this case, the cleaning blade is disposed so that an angle &#x3b1; between a line F perpendicular to a line E connecting the center of the cleaning roller and the free end of the cleaning blade, and the cleaning blade is in a range of 35&#xb0; or more and less than 60&#xb0; .

Developing device with cleaning roller and cleaning blade

An image forming apparatus detects a current flowing between a developer carrying member and a cleaning member is detected for each of a plurality of toner images when a region on the developer carrying member passes through the cleaning member, and a potential difference to be used during image formation between the developing voltage and an image portion potential is set on the basis of a value of the detected current for each of the plurality of toner images. An absolute value of the potential difference to be used during image formation is larger than the potential difference between the developing voltage and the image portion potential whose absolute value is smallest among potential differences between the developing voltage and the image portion potential to be used for developing a toner image of which the value of the current detected is in a predetermined range among the plurality of toner images.

To provide an image forming apparatus that includes a plurality of image forming units and executes a mode for image formation by using a selected image forming unit, the image forming apparatus being able to restrict a decrease in productivity and restrict an image defect such as a lack of part of an image output during the execution of the mode. In a monochrome mode for forming an image only with a black toner, in the first image forming unit, a toner is caused to adhere to a region on a photosensitive body corresponding to a sheet interval and hence the toner is supplied to a cleaning blade by applying a development bias to a developing unit without applying a direct-current voltage to a charger of a color image forming unit not used for the image formation. Also, an alternating-current voltage is applied to the charger when the region on the photosensitive body from which the toner is removed by the cleaning blade passes through the charger.

An image forming apparatus includes an image bearing member on which an electrostatic image is to be formed; a developing device for accommodating a developer including toner and a carrier and for developing the electrostatic image with the developer; a developer supply container, detachably mountable to a main assembly of the image forming apparatus, for accommodating a supply developer including the toner; a detecting device for detecting a toner content of the developer in the developing device; a supply control device for controlling an operation of supplying the supply developer into the developing device on the basis of a detection result of the detecting device and a density target value; a memory element, provided on the developer supply container, for storing information relating to elapse time from a manufacturing date of the supply developer; and a controller for determining the density target value in accordance with the information, wherein the supply control device controls the supply operation on the basis of the detection result of the detecting device and the density target value determined by the controller.

A developing apparatus of this invention includes development units each including a developing powder accommodating unit for accommodating developing powder, a screw which agitates and conveys developing powder and a developing powder bearing member which bears developing powder to develop an image and a developing powder supply unit which supplies developing powder to the developing powder accommodating unit and develops an electrostatic latent image formed on an image bearing member at a development position. The developing powder supply unit supplies developing powder to a lower area than a screw in the vertical direction of the developing powder accommodating unit in the time the development unit has been in the developing position.

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Kashiwa, Japan

Ryota Fujioka