Brother Kogyo Kabushiki-Kaisha

Hideaki Deguchi

Keita Hironaka

Fumikazu Sato

Naoya Kamimura

Mitsuru Horinoe

Yusuke Ozaki

Satoru Ishikawa

Masahiro Ishii

Soichiro Nishimura

Motoaki Mushika

Hikaru Yoshizumi

Shougo Sato

Makoto Hattori

Koji Abe

Katsumi Inukai

Tsutomu Suzuki

Makoto Ishii

Toshio Furukawa

Fumio Morita

Atsushi Miwa

Yoshiteru Hattori

Tsuyoshi Suzuki

Soichiro Mase

Hidenori Hisada

Hiroshi Tokuda

Junji Uehara

Takeshi Takami

Yusuke Yanagihara

An image forming apparatus including an image carrier, a transfer member, an application circuit and a controller configured to acquire a transfer resistance value, the transfer resistance value being a value of electric resistance between the image carrier and the transfer member, determine whether the acquired transfer resistance value is less than or equal to a reference resistance value, and control the application circuit, in response to determining that the acquired transfer resistance value is less than or equal to the reference resistance value, to perform a current control process to cause a value of a transfer current passing through the transfer member becomes a target current value.

Image forming apparatus and transfer power supply controlling method

A drum cartridge and a method are disclosed. An example drum cartridge includes a photosensitive drum, a first cleaning roller positioned to a side of the photosensitive drum. The drum cartridge includes a lever positioned at an outer surface of the drum cartridge. The outer surface of the drum cartridge is positioned toward the side of the photosensitive drum. The lever is extendable in a second direction different from the first direction, and the lever is pivotable with respect to the outer surface of the drum cartridge about a second axis extending in the first direction. The lever is pivotable between an extended position and a retracted position. The drum cartridge includes an engagement portion movable with pivoting of the lever between an engaged position when the lever is in the extended position and a disengaged position when the lever is in the retracted position.

Drum cartridge with movable cleaning roller

An image forming apparatus includes: a photosensitive drum; a transfer roller configured to form a nip portion; and a sheet guide that is configured to guide a recording sheet. The sheet guide comprises: a conductor configured to face the recording sheet, and insulating ribs that are arranged corresponding to a printing area of the recording sheet in a width direction and are configured to protrude from the conductor to guide the recording sheet. The conductor comprises: a central portion, and a pair of end portions and are configured to protrude towards the recording sheet from a virtual plane extending from the central portion in the width direction. Protrusion amounts of the end portions with respect to the central portion are smaller than a protrusion amount of each rib from the central portion of the conductor.

Image forming apparatus

In a transfer device, a flexible guide plate is disposed in a position upstream relative to a transfer position along a medium conveyance path, such that a first side of the guide plate faces to a recording medium being conveyed along the medium conveyance path. The guide plate has a downstream end portion that is angled by bending the guide plate. A support frame supports an upstream end portion of the guide plate and extends in a downstream direction beyond the downstream end portion to form an extension portion which is disposed opposite to a second side of the guide plate and toward which the downstream end portion extends obliquely downstream. The extension portion has a recess/hole formed in a position separated in an upstream direction from a first edge of the extension portion, to allow the downstream end portion to be moved without being blocked by the extension portion.

Transfer device

An image forming apparatus or cartridge is provided that includes an image carrier configured to be rotated while carrying a developer and transfer the developer onto a recording sheet at a transfer position. The image forming apparatus or cartridge may include a separating member disposed downstream from the transfer position in a rotating direction of the image carrier. The separating member may include a contact portion configured to contact the image carrier to separate the recording sheet from the image carrier, and an aperture configured to allow the developer to pass through the separating member from a first side of the separating member to a second side of the separating member opposite the first side, wherein the aperture is positioned farther away from the image carrier than the contact portion.

Image forming apparatus and cartridge

In a transfer device, a first side of a flexible guide plate faces to a recording medium being conveyed along a medium conveyance path to guide the recording medium toward an image carrying member. A support frame supports an upstream end portion of the guide plate, and includes an opposite portion disposed from and opposite to a second side (reverse to the first side) of the guide plate and a rib configured to protrude from the opposite portion toward the medium conveyance path. The rib has a first edge which is positioned at an upstream side and beyond which the guide plate protrudes downstream. The rib has an inclined surface extending from the first edge in a direction obliquely downstream toward the image carrying member. The guide plate includes an indentation to allow the guide plate to be deflected without being blocked by the rib.

A recording sheet guide structure configured to guide a recording sheet conveyed between an image carrier and a transfer part, including: a pair of first guide parts including first ridgeline parts which are configured to respectively slidingly contact with a transfer surface side of both end portions of a first recording sheet having a first width; and a pair of second guide parts including second ridgeline parts which are configured to respectively slidingly contact with a transfer surface side of both end portions of a second recording sheet having a second width narrower than the first width, wherein the pair of second guide parts is positioned at an inner side of the pair of first guide parts in a width direction and is arranged at a downstream side than the pair of first guide parts in a conveyance direction of the recording sheet.

Recording sheet guide structure and cartridge

A cartridge and an image forming apparatus including the cartridge are provided. The cartridge includes a casing, an image carrier disposed in the casing and configured to be rotated while carrying a developer and transfer the developer onto a recording sheet at a transfer position, and a separating member disposed in the casing and configured to contact the image carrier at a downstream side of a rotating direction of the image carrier with respect to the transfer position to separate the recording sheet from the image carrier. The separating member has a sheet shape including a first surface opposed to the image carrier and a second surface opposite to the first surface. The second surface is roughened by a roughening processing.

A transfer apparatus includes a transfer roller which transfers developer on an image carrier onto a recording medium conveyed along a conveyance path, a supporting frame which is provided at an upstream of a transferring portion where the image carrier and the transfer roller are closest, in the conveyance path, and is provided at a side of the transfer roller with respect to the conveyance path, a flexible guide member which has a thin plate shape, and is attached to the supporting frame at an upstream of the transferring portion in the conveyance path to guide the record medium to the transferring portion, and a inflexible protrusion supporting member which is provided on the supporting frame between the transferring portion and the guide member in the conveyance path, and which protrudes toward the conveyance path to support a trailing edge of the record medium after passing the guide member.

Transfer apparatus

A transfer apparatus includes a transfer roller which transfers developer on an image carrier onto a conveyed recording medium at a transferring portion, a supporting frame, a flexible guide member attached to the supporting frame to guide the record medium to the transferring portion, and a inflexible protrusion supporting member which is provided on the supporting frame between the transferring portion and the guide member and protrudes to support a trailing edge of the record medium after passing the guide member. The guide member includes a swing portion which is provided at one end side at a downstream thereof. The protrusion supporting member is provided to abut the guide member while the guide member does not protrude from the protrusion supporting member to a side of the transferring portion when the swing portion of the guide member swings by abutting the record medium.

An image forming apparatus including an image carrier; a transfer member, which is provided in a face-to-face relation to the image carrier and to which a transfer bias is applied; a first sensor that measures a resistance value of a section between the image carrier and the transfer member; and transfer bias controlling means. The transfer bias controlling means controls the transfer bias, which is applied to the transfer member based on a first resistance value measured by the first sensor before a recording sheet enters a nip between the image carrier and the transfer member and also based on a second resistance value measured by the first sensor when the recording sheet has entered the nip between the image carrier and the transfer member.

A photosensitive body for electro-photography includes an electrically conductive photosensitive drum, an electrically conductive shaft, and an electrically conductive contact member. The photosensitive drum is rotatable relative to the shaft. The shaft includes a cylindrical shaft body and a metal coating formed on the outer surface of the shaft body and made from an electrically conductive material having an ionization tendency lower than that of a substrate of the shaft body. The contact member has an engagement portion in fitting engagement with an inner peripheral surface of the drum body, and has a contact portion resiliently and slidingly contacting the shaft to provide an electrical contact between the photosensitive drum and the shaft. The contact portion is made of a material whose ionization tendency is higher than that of the metal coating.

Photosensitive body having electrical connection arrangement

A photosensitive body for electro-photography includes a photosensitive drum, a shaft aligned with a center axis of the photosensitive drum, and a contact member. The photosensitive drum is rotatable relative to the shaft, and the shaft includes a cylindrical shaft body made from an electrically conductive metal, and an electrically conductive metal coating formed on an outer surface of the shaft body. The contact member has an engagement portion in fitting engagement with an inner peripheral surface of the drum body, and a contact portion resiliently and slidingly contacting the shaft to provide an electrical contact between the photosensitive drum and the shaft. The metal coating and at least a surface of the contact portion in direct contact with the outer surface of the shaft body are made from a material identical to each other.

An image forming apparatus has a transfer unit, a power supply unit that takes a value of a current imparted to the transfer unit as a control target and that supplies power conforming to the value of the control target to the transfer unit; and a determination unit that acquires a detection value of a voltage detection unit and a detection value of a current detection unit and that determines, as a control target value for the power supply unit, an optimum value for the control target derived from a characteristic line showing a relationship between both detection values or a detection value of the voltage detection unit and an optimum value of the control target. The characteristic line is a line showing a relationship of a change in the absolute value of the optimum value for the control target shifting from an increasing tendency to a decreasing tendency with an increase in both detection values or the detection value of the voltage detection unit.

Control of a power supply for a transfer unit in an image forming apparatus

A drum unit includes a photoconductor drum, a charger, a cleaning brush, and a drum unit case. The charger and the cleaning brush are disposed in such a manner as to face the circumferential surface of the photoconductor drum. The charger and the cleaning brush are fixed to a charger support portion of the drum unit case. The charger support portion has a filler protrusion. The filler protrusion is provided so as to fill the space between the charger and the cleaning brush.

Growing community of inventors

Nagoya, Japan

Hideaki Deguchi