Canon Kabushiki Kaisha

Eiichiro Teshima

Seiji Yokoyama

Yoshiteru Kaida

Hiroaki Ogata

Eihiro Sakaki

Fumihiro Ueno

Yoshimi Ogasawara

Tetsuya Kobayashi

Kaoru Sato

Akihiro Nakamura

Yasuyuki Ishii

Hiroshi Sasame

Mitsugu Tanaka

Takashi Kawana

Yuki Nishizawa

Atsuya Takahashi

Tomoyuki Okada

Takuya Mukaibara

Ryuichi Yoshizawa

Takeo Shoji

Akira Torisawa

Tatsuto Tachibana

Norihisa Hoshika

Tadashi Okanishi

Takashi Hibi

Hidekazu Tominaga

Kazuhisa Maruyama

Tomohiro Hashimoto

Yasuo Ito

Masaki Ohtake

In a case in which an image forming apparatus determines that a replaceable unit is replaced in a first state, in which removal of the replaceable unit is inhibited, the image forming apparatus performs control to switch from the first state to a second state, in which removal of the replaceable unit is allowed.

Image forming apparatus

Image forming apparatus with control of replacement of process cartridge

An apparatus comprising a first control unit that executes density correction processing on image data and generates an image signal, an image forming unit that forms an image on a recording medium on the basis of the image signal, and a second control unit that controls the image forming unit. The first control unit includes a specifying unit that transmits specifying information relating to the density correction processing to the second control unit. The second control unit includes an acquisition unit that acquires a parameter relating to the image forming apparatus, and an estimation unit that estimates a plurality of image densities corresponding to tone levels identified by the specifying information transmitted from the first control unit on the basis of the parameter acquired by the acquisition unit and transmits the plurality of image densities to the first control unit.

Density acquisition assistance technique for image forming apparatus

Image forming apparatus selectively restricting removal of cartridge

A double-feed detection apparatus includes a sensor configured to detect double feed of transfer materials conveyed along a conveying path, and a control unit configured to execute detection of the transfer material under conveyance plural times with the sensor, and to determine the double feed of the transfer materials based on detection results. The control unit determines a detection timing based on both a distance along the conveying path from the sensor to an image forming unit which forms an image on the transfer material and a length of the transfer material in the feed direction.

Double-feed detection apparatus and image forming apparatus

An image forming apparatus is capable of more accurately detecting the relationship between an actual amount of color deviation and an estimated amount of color deviation. The image forming apparatus forms a color deviation detection mark at timing when the estimated amount of deviation reaches a threshold value. The timing is different from the timing when it is determined that it is necessary to perform normal calibration. The image forming apparatus determines the relationship between the actual amount of deviation of an image forming position from a reference and the estimated amount of deviation to set an estimating unit for estimating the amount of deviation.

Image forming apparatus calculating an amount of deviation of an image forming position from a reference

An image forming apparatus to which a paper handling unit is connected thereto is provided. The image forming apparatus detects the size of a sheet in a direction in which the sheet is conveyed for image formation. The image forming apparatus outputs sheet size mismatch information indicating that the size of the sheet does not match a predetermined size to the paper handling unit before a size detecting operation thereof has been completed detecting the trailing edge of the sheet is greater than the predetermined size.

An image forming apparatus includes a plurality of photosensitive drums, a plurality of developing devices, an intermediate transfer medium, primary transfer members, and a secondary transfer member for transferring toner images onto a transfer material. A full-color mode and a monocolor mode are selectively carried out. The image forming apparatus also includes a CPU for adjusting the length of a non-image forming region, and an intermediate-transfer-medium movement controller. The CPU brings about a switching state in which an image forming region lies between a primary transfer position on the most downstream one of the photosensitive drums and a secondary transfer position and in which non-image forming regions simultaneously lie at the primary transfer position and at the secondary transfer position. The intermediate-transfer-medium movement controller switches between the full-color mode and the monocolor mode during the switching state.

Image forming apparatus that has a full-color mode and a monocolor mode, and image forming apparatus that can adjust the length of a non-image forming region during mode switching state

In an image forming apparatus and an image forming method, a paper position aberration detecting sensor including a light emitting element and a light receiving element is disposed in the paper conveying path of the image forming apparatus. The amount of paper position aberration in paper conveyance is detected by a counter, and on the basis of the result of the detection, a CPU controls the writing start position of a printed image.

An image forming apparatus includes an image bearing member, a container for containing a developer removed from the image bearing member, a detector for detecting an amount of developer removed from the image bearing member and contained in the container, and a failure detector for detecting a failure of the developer amount detector on the basis of the degree of use of the image bearing member and a detection result of the developer amount detector.

Image forming apparatus having means for detecting amount of developer used and means for detecting failure of used developer amount detecting means

A life informing device for a charge body includes a body to be charged, and a charging member for charging the charge body. The charging member is adapted to receive an oscillating voltage and to be in contact with the charge body during the charging operation. Also provided is an informing device for visually or acoustically informing the user whether the charge body reaches the end of the life time thereof, based on an accumulated time of the application time during which the oscillating voltage is applied.

Service life informing device for charged member, informing method

While the electric power source is turned on, capacitor 1 is charged to a voltage EO by a direct current constant voltage supplier through transistor 4. When the electric power is disconnected, transistor 4 is switched off to discharge capacitor 1 through resistor R1. When the power source is turned on, the voltage of capacitor 1 is read by A/D converter to be produced and stored in CPU 12 memory. Then transistor 4 is switched on to charge capacitor 1 to the voltage EO. Then transistor 4 is switched off and transistor 5 is switched on to discharge capacitor 1 through resistor R2 and a counter stars. When the voltage of capacitor 1 reduces to the same voltage stored in the memory, transistor 5 is switched off to stop the counter and to obtain the counted value t2. Then transistor 4 is switched on to prepare for the next operation. The time lapse t1 after the power source being turned off is obtained by a formula (R1/R2).times.t2.

Device for measuring time lapse after turn off of power source and

A color image forming apparatus forms a color image by superposing images of plural colors in plane-sequential manner. In the color image forming apparatus, the amount of aberration between the detection signal for the recording medium for the first color and the horizontal synchronization signal is measured by a counter, and the start timing of image formation of the second and subsequent colors is controlled by a delay device, according to the measured amount of aberration.

Growing community of inventors

Ashigarakami-gun, Japan

Eiichiro Teshima