Canon Kabushiki Kaisha

Yoritsugu Maeda

Jiro Shirakata

Dai Kanai

Jun Nakazato

Yukihiro Fujiwara

Eijiro Atarashi

Jun Nakagaki

Satoshi Atarashi

Takashi Fujimori

Satoru Kanno

Koji Doi

Hiromichi Tsujino

Junichi Noguchi

Kazuhisa Koizumi

Akira Morisawa

Tetsuya Nozaki

Manabu Koseki

An image forming apparatus includes a sheet feeding cassette configured to store a recording sheet, a conveyance unit configured to convey the recording sheet stored in the sheet feeding cassette, and an image forming unit configured to form an image on a photo sensitive member, and to transfer the image onto the recording sheet conveyed by the conveyance unit. A power supply unit is configured to convert an alternating current (AC) voltage of a commercial power supply into a direct current (DC) voltage, and is configured to supply the AC voltage and the DC voltage. A first heater heats the sheet feeding cassette, and generates heat with the AC voltage supplied by the commercial power supply, and a second heater heats the photosensitive member of the image forming unit, and generates heat with the DC voltage supplied by the power supply unit.

Image forming apparatus having a heater that generates heat using alternating current voltage and a heater that generates heat using a direct current voltage

An image forming apparatus includes a rotary member which transports a recording material; a first detecting unit which is provided upstream of the rotary member in a transport direction of the recording material and detects the recording material; a second detecting unit which is provided downstream of the rotary member in the transport direction of the recording material and detects the recording material; a driving unit which drives the rotary member; a control unit which controls the driving unit to rotate and stop the rotary member; and stopping units which operate independently of the control unit and forcibly stop the driving unit based on detection results of the first detecting unit and the second detecting unit.

Image-forming apparatus with forcible stopping of rotary member

When a detection signal indicates that a switch has switched off, a first relay cuts off the supply of alternating current from a commercial alternating-current source to a third DC power source and terminates a first load such as a motor and a high-voltage power source. When the detection signal indicates that the switch has switched off, a control circuit executes shutdown processing for safely terminating an operation of a second load such as a hard disk drive. When the shutdown processing is complete, the control circuit outputs a signal for terminating an operation of a second DC power source. When the shutdown signal is input, a second relay terminates the operation of the second load by cutting off the supply of the alternating current from the commercial alternating-current source to a second DC power source.

Power supply apparatus for safety load shutdown and image forming apparatus including the same

A rotary driving apparatus that is capable of controlling a rotational speed correctly even when an anomaly occurs. A drive unit rotates a rotating member. A rotating body is rotated with the rotating member. A detection unit detects scales formed on the rotating body. A calculation unit calculates rotation information about the rotating member based on the detection result by the detection unit. A control value setting unit sets a control value to a predetermined value when the rotation information falls outside a predetermined range and a count of determinations that the rotation information falls outside the predetermined range is smaller than a predetermined count, and sets the control value based on the rotation information when the rotation information falls outside the predetermined range and the count of determinations is larger than the predetermined count. A control unit controls the drive unit based on the set control value.

Rotary driving apparatus, control method therefor, storage medium storing control program therefor, and image forming apparatus

A motor control apparatus for controlling a DC motor includes a first detection unit configured to detect an angular velocity of the DC motor, a driven member configured to be driven by the DC motor, a control unit configured to perform, during start-up of the DC motor, feed forward control for changing a control value used for controlling drive of the DC motor from a first control value corresponding to an angular velocity smaller than a target angular velocity to a second control value corresponding to the target angular velocity, and to change the feed forward control to feedback control for controlling the control value based on a detection result by the first detection unit to keep the DC motor at the target angular velocity, and a second detection unit configured to detect whether the driven member has been replaced.

Motor control apparatus and image forming apparatus

A motor control apparatus that controls a DC motor includes a detection unit configured to detect angular speed of the DC motor, a driven member configured to be driven by the DC motor, and a control unit configured to increase, when starting to drive the DC motor, a control value for controlling driving of the DC motor from a first control value to a second control value at a predetermined increase rate, wherein the control unit detects a start-up characteristic of the DC motor based on a detection result of the detection unit, and corrects the first control value or the increase rate according to a result of comparing a detected start-up characteristic and a predetermined start-up characteristic such that the start-up characteristic of the DC motor becomes closer to the predetermined start-up characteristic.

A control unit sets a first feedback gain for suppressing an angular speed variation of a first frequency, which causes a misalignment of images to be overlaid with each other, to the first nd feedback unit in a first image forming mode in which images formed on the first and the second image carriers are overlaid, and sets a second feedback gain for suppressing an angular speed variation of a second frequency, which causes a periodic uneven density on an image that is to be formed with a uniform density, to the first feedback unit in a second image forming mode in which an image is formed using the first image carrier.

Image forming apparatus

A control unit sets a first feedback gain for suppressing an angular speed variation of a first frequency, which causes a misalignment of images to be overlaid with each other, to the first feedback unit in a first image forming mode in which images formed on the first and the second image carriers are overlaid, and sets a second feedback gain for suppressing an angular speed variation of a second frequency, which causes a periodic uneven density on an image that is to be formed with a uniform density, to the first feedback unit in a second image forming mode in which an image is formed using the first image carrier.

An image forming apparatus includes a rotatable belt member; a stretching roller for stretching the belt member; a plurality of line like marks which are arranged in a rotational direction of the belt member and are formed stepwisely on a surface of the belt member, the marks being tilted from a rotational axis direction of the belt member at least at end portions thereof on sides close to an end surface of the belt member; and control means for controlling rotation of the belt member on the basis of a result of detection of the marks.

Belt driving apparatus having belt with detection marks

A motor control apparatus for controlling a DC motor includes a detection unit configured to detect an angular speed of the DC motor, and a control unit configured to, when the DC motor is accelerated, increase a control value that controls a driving of the DC motor at a constant rate from a first control value corresponding to an angular speed lower than a target angular speed up to a second control value corresponding to an angular speed higher than the target angular speed, and switch the control value that controls the driving of the DC motor to a control value corresponding to the target angular speed in response to the detection result of the detection unit reaching the target angular speed.

An image-forming apparatus includes an image-bearing member configured to bear an image, a transfer belt to which the image on the image-bearing member is transferred and configured to transfer the image onto a sheet, a first drive unit configured to drive the image-bearing member to rotate, a second drive unit configured to drive the transfer belt to rotate via a speed reduction member interposed therebetween, a detection unit configured to detect a circumferential speed of the transfer belt, and a control unit configured to control the first drive unit in accordance with the circumferential speed of the transfer belt detected by the detection unit.

Image-forming apparatus

A rotary member apparatus includes a main drive unit configured to apply a driving torque to a photosensitive drum through a drive transfer unit, a torque limiter configured to limit the driving torque transmitted from the main drive unit to the photosensitive drum, a compensation drive unit configured to apply a torque for adjusting an angular velocity of the photosensitive drum, an encoder configured to detect the angular velocity of the photosensitive drum, and a compensation drive controller configured to control the torque applied by the compensation drive unit on the basis of a detection result obtained by the encoder.

Rotary member driving apparatus

Adjustment processing is suitably executed in accordance with the type of post processing. To accomplish this, an image forming apparatus includes, for example, an adjustment part, specifying part, and control part. The adjustment part performs at least one of adjustment operation for an image formation position and adjustment operation for an image formation density by forming adjustment patterns using a developing material on an image carrier and measuring the adjustment patterns. The specifying part specifies the size of an image to be formed on a sheet and the content of post processing in case of executing a job which requires post processing on the sheet. The control part controls, in accordance with the size of the image and the content of the post processing, whether to perform the adjustment operation by the adjustment part concurrently with the formation of an image made from a job requiring post processing.

Image forming apparatus including adjustment processing and control method therefor

An image heating roller for heating a toner image on a recording material. The image heating roller includes a heat generation layer for generating heat by a microwave introduced into a hollow portion of the image heating roller. The image heating roller further includes a blocking layer, provided on the heat generation layer, for substantially blocking passing of the microwave.

Image heating roller, image heating heater, with microwave blocking layer

An image forming apparatus capable of carrying out color misregistration correction at an appropriate time and providing a high-quality image free from color misregistration. A toner image is formed on the basis of an input image information signal. A width of the toner image is determined on the basis of the input image information signal, before forming the toner image in a predetermined area. The width of the toner image formed in the predetermined area is detected. The detected width of the toner image is compared with the determined width of the toner image. It is judged on the basis of the comparison result whether or not color misregistration is present.

Growing community of inventors

Moriya, Japan

Yoritsugu Maeda