Canon Kabushiki Kaisha

Masaaki Moriya

Hidehiko Kinoshita

Atsushi Nakagawa

Jun Yamaguchi

Masayuki Hirano

Manabu Mizuno

Kenji Fukushi

Yousuke Hata

Mitsuhiro Sugeta

Norio Negishi

Fumitaka Sobue

Koichiro Ino

Noriaki Adachi

Satoshi Atarashi

Yosuke Hata

An image forming apparatus includes an optical sensor configured to measure reflected light from a test image on the image carrier. The optical sensor includes a printed circuit board, with a light-emitting element provided on a first surface of the printed circuit board, and with the light-emitting element being configured to irradiate the test image on the image carrier with light. The optical sensor also includes a light-receiving element provided on the first surface of the printed circuit board, with the light-receiving element being configured to receive the reflected light from the test image on the image carrier. A connector is provided on a second surface of the printed circuit board opposite to the first surface of the printed circuit board, with a cable for controlling the optical sensor being connected to the connector. A support member is configured to support the optical sensor so that the first surface of the printed circuit board faces a surface of the image carrier, and a controller is configured to control the image forming unit based on a result of the reflected light from the test image measured by the optical sensor. A direction in which the cable is inserted into the connector is orthogonal to the second surface of the printed circuit board.

Technique for attaching optical sensor to image forming apparatus

A developing device includes a developer carrying member configured to carry a developer, containing toner and a carrier, for developing an electrostatic latent image formed on an image bearing member, a developer container configured to accommodate the developer, and an oscillation circuit including a resonance circuit including a coil and a circuit portion containing a capacitor and configured to oscillate a signal for detecting a toner concentration of the developer accommodated in the developer container. The coil is formed integrally with the developer container by a metal film, and the coil is disposed on an inner wall surface of the developer container.

Developing device

A printed circuit board has a first mounting surface and a second mounting surface. A light-emitting element and a light-receiving element are mounted on the first mounting surface. An electronic component for driving the light-emitting element is mounted on the second mounting surface. A supporting member supports the printed circuit board. The supporting member has a through-hole in which the electronic component is inserted when the printed circuit board is supported by the supporting member.

An image forming apparatus that can detect a leading edge of a tabbed sheet after skew correction with high accuracy and without increasing a size of the apparatus. A transfer unit transfers a toner image to the sheet, the skew of which having been corrected based on a detection result of a first skew detection unit, while the toner image is controlled to be synchronized with the sheet based on the detection result of the first skew detection unit and a detection result of a second skew detection unit.

Image forming apparatus including skew correction mechanism, control method therefor, and storage medium

The present invention provides a sheet conveying apparatus and an image forming apparatus capable of preventing occurrence of skew feeding when correcting sheet lateral deviation. A pair of lateral-shift correcting rollersto correct positional deviation in the sheet width direction based on positional deviation quantity detected by a lateral-registration detection sensoris controlled after controlling a skew feeding correcting rollerso as to correct sheet skew feeding based on skew-feeding quantity at a sheet leading edge detected by skew-feeding detection sensorsand. Then, skew-feeding quantity of the sheet leading edge to be detected by the skew-feeding detection sensorsandfor correcting skew feeding of the next sheet is adjusted with skew-feeding quantity at the sheet trailing edge detected by the lateral-registration detection sensorafter positional deviation in the sheet width direction is corrected.

Image forming apparatus

An image forming apparatus includes an endless belt type transfer member configured to carry an image formed with developer of a plurality of colors, a drive roller configured to drive the transfer member by rotating while contacting the transfer member, a first detection unit configured to detect a mark provided on the transfer member, a second detection unit configured to detect the mark at a position different from the position of the first detection unit in a conveyance direction of the transfer member, and a correction unit configured to correct a conveyance speed of the transfer member using a difference between respective times at which the first and second detection units detect the mark. The first and second detection units are located such that an interval between respective positions at which the first and second detection units detect the mark is an integral multiple of a perimeter of the drive roller.

Image forming apparatus with intermediate transfer belt speed detection unit

An image forming apparatus which can reduce color shift and image blurring caused by increased temperature in the apparatus and form high-quality images without causing an increase in the cost and size of the apparatus. An image sensor unit reads surface patterns of an intermediate transfer belt. A digital signal processor (DSP) controls the movement of the belt in a transverse direction perpendicular to a moving direction thereof based on the surface patterns of the belt read by the image sensor unit.

A sheet conveying device for conveying a sheet includes a displacement-amount detector configured to detect an amount of displacement of a conveyed sheet from a conveyance reference in a width direction being substantially perpendicular to a sheet conveying direction and a plurality of sheet conveying roller portions configured to be shiftable in a direction substantially perpendicular to the sheet conveying direction while pinching the sheet having the amount of displacement detected by the displacement-amount detector. Before the sheet reaches the sheet conveying roller portions, the sheet conveying roller portions are shifted based on the amount of displacement detected by the displacement-amount detector from a conveyance-reference position in a direction in which the sheet is displaced. After the sheet reaches the sheet conveying roller portions, the sheet conveying roller portions are shifted while pinching the sheet so as to reduce the amount of displacement.

Sheet conveying device and image forming apparatus

A CMOS sensor scans an image that is either on a transfer material carrier or on a transfer material that is placed on the transfer material carrier. A sampling timing controller samples an image signal at a predetermined sampling rate and computes a position of a predetermined pattern contained within the sampled image signal. A speed computation processor computes a moving speed of either the transfer material carrier or the transfer material, based on the position of the predetermined pattern thus sampled at the predetermined sampling rate and computed, as well as the predetermined sampling rate. The image region that the CMOS sensor scans is determined in accordance with the rotational speed of the drive motor and the sampling rate.

Image forming apparatus employing an electrophotographic method

When an abnormality factor occurs in a second heating device, a sheet located upstream of a branch portion is discharged onto a discharge tray through a second conveying path. After the abnormality factor in the second heating device is removed and the sheet discharged to the discharge tray through the second conveying path is set in a paper refeeding tray, a sheet feeding portion feeds the sheet set in the paper refeeding tray to the second heating device.

Image forming apparatus and sheet heating apparatus

An inexpensive laser drive device which is capable of driving a laser for emission of an appropriate amount of light. Electric currents supplied from a supply current control device formed in an integrated circuit to a plurality of predetermined ports of the integrated circuit are turned on and off by switching devices in response to a signal from a signal output device of the supply current control device, and the on currents are supplied, as a driving current, from the supply current control device to a laser beam-emitting device through corresponding ones of the predetermined ports and resistors externally attached to these ports. A generator device formed in the integrated circuit generates a pulse signal for turning on and off a laser beam based on image data.

Laser drive device and image forming apparatus incorporating the same

A fixing apparatus includes a fixing rotary body; a rotary body provided with an interval from the fixing rotary body; an endless belt rotating in a condition in which it is wound around the fixing rotary body and the rotary body; a pressure rotary body which makes a pressure contact with the fixing roller across the endless belt; a heater for heating a recording material conveyed by the endless belt; a cooling unit for cooling a recording material conveyed by the endless belt and heated by the heater; and an error detecting member for detecting an error in conveyance of the recording material. When an error is detected in the downstream of the cooling unit by the error detecting member, the recording material is stopped after the recording material on the endless belt is conveyed to a position in which the cooling unit cools the recording material.

Fixing apparatus and image forming apparatus

A signal generating apparatus for generating a first pulse width modulation (PWM) signal and a second PWM signal synchronous with the first PWM signal, the first and second PWM signals controlling a switching power supply having a transformer with a plurality of secondary windings. The on-widths of the first and second PWM signals are adapted to be controlled independently, and the on-width of the second PWM signal is adapted to be increased or decreased without being affected by an increasing/decreasing state of the on-width of the first PWM signal. To this end, when the on-width of the second PWM signal is increased or decreased, the data used for increasing or decreasing the second PWM signal is corrected in accordance with the change state of the on-width of the first PWM signal.

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Moriya, Japan

Masaaki Moriya