Canon Kabushiki Kaisha

Kubota Corporation

Other

Takahiro Ishihara

Tomohisa Itagaki

Nobuhiko Zaima

Yasuhito Shirafuji

Toshio Toshima

Takashi Aoki

Takashi Yokomizo

Akira Ohtsuki

Kazuhiko Isoda

Toshiyuki Iwamoto

Shogo Kaneko

Kazuya Ito

Noriyuki Arakawa

Masayuki Ohkawa

Yuki Hieda

Atsushi Maki

Atsuichi Namariyama

Takashi Tazoh

Shota Yamada

Hideyuki Mano

A pipe joint includes: a sealing member, having an annular shape, which is provided between the outer circumferential surface of a spigot and an inner circumferential surface of a socket; a pushing ring to push the sealing member into the socket, the pushing ring being fitted onto the spigot; and a separation preventive member configured to engage with the spigot protrusion part in a pipe-axial direction to prevent a separation of the spigot from the socket. The separation preventive member is provided between an inner circumferential surface of the pushing ring and the outer circumferential surface of the spigot. The sealing member is provided along an outer circumferential surface of the spigot protrusion part and includes a compression part. The compression part is compressed in a pipe-radial and is located, in the socket, upstream of the spigot protrusion part in an insertion direction in which the spigot is inserted.

Pipe joint, separation prevention member, and method of connecting pipes

An image forming apparatus configures a normal transfer potential in a yellow primary transfer unit, and configures a transfer potential which does not cause any retransfer phenomenon of a yellow measurement image in image carriers located on the downstream side of the yellow primary transfer unit. When a color difference obtained from a reference density and a density of a measurement image on an intermediate transfer belt becomes equal to or larger than a prescribed value, the image forming apparatus determines that multinary-color density adjustment is required.

Adjustment of image density, using a density adjustment condition, in image forming apparatus

An image forming apparatus includes; an exposure unit configured to perform, based on the image data, first exposure for a photosensitive member and second exposure for the photosensitive member exposed by the first exposure; a determination unit configured to determine a type of the image to be formed based on image data; and a control unit configured to control the exposure unit such that a difference in an exposure amount between the first exposure and the second exposure performed based on the image data when the type of the image is a character is larger than the difference in the exposure amount between the first exposure and the second exposure performed based on the image data when the type of the image is a picture.

Image forming apparatus for performing exposure a plurality of times

An image forming apparatus capable of suppressing density unevenness of a toner image formed on a photosensitive member. A light amount of a light beam that exposes an end portion of the photosensitive member is made different from a light amount of a light beam that exposes a central portion thereof in order to suppress a density difference between a toner image density at the central portion of the photosensitive member and that at the end portion thereof in a scanning direction of the light beams.

Image forming apparatus having photosensitive member exposed to plural beams, and control apparatus for light source of image forming apparatus

An image forming apparatus includes an image forming unit having an exposure unit and a developing unit; a detection unit configured to detect a thickness and an area ratio of a toner layer of a pattern image formed by the image forming unit; a storage unit configured to store data indicating permissible ranges for the thickness and the area ratio of the toner layer; and a correction unit configured to change, when the thickness or the area ratio of the toner layer detected by the detection unit falls outside the corresponding permissible range indicated by the data stored in the storage unit, a spot diameter of the laser beam so that the thickness and the area ratio of the toner layer respectively fall within the permissible ranges.

Image forming apparatus for detecting and correcting thickness and area ratio of toner layer

An apparatus includes a forming unit; a reading unit; a conversion unit converting a signal corresponding to the image read by the reading unit into a signal indicating a density value; a correction unit performing tone correction on the density value of the signal output by the conversion unit; and a control unit controlling a tone correction setting in the tone correction unit by controlling the reading unit to read a tone correction image that was formed on a recording material by the forming unit. When controlling the tone correction setting, the control unit further changes a setting for image formation in the forming unit and a setting for conversion into a density value in the conversion unit according to the recording material used in the control of the tone correction setting.

Image forming apparatus in which tone correction setting is controlled

An image forming apparatus that is capable of reducing a sequential variation of graininess and keeping imaging quality. An exposure unit exposes the photoconductor to a light beam to form an electrostatic latent image. A development unit develops the electrostatic latent image with a toner. A change unit changes a height of toner image by changing an exposure spot area of the light beam on the photoconductor. A formation unit forms test patterns corresponding to different exposure spot areas on a recording sheet. A read unit reads the test patterns. A control unit detects graininess of each test pattern based on information about the test patterns read by the read unit, determines an exposure spot area where the graininess becomes good relatively, and controls the height of toner image on the photoconductor by setting the exposure spot area determined so as to be an exposure spot area for image formation.

Image forming apparatus and image forming method of electrophotography

Restricting a screen line number to prevent degradation in graininess depending on the type of recording paper causes a problem in which the image quality of output matter deteriorates. An image forming apparatus according to the present invention changes an exposure area for one pixel used in image formation in accordance with recording paper in consideration of differences in the influence of the height of toner on graininess depending on recording paper.

Image forming apparatus

A stress transmission device arranged between a pile head of a foundation pile and an upper structural portion for transmitting stress between the foundation pile and the upper structural portion, to a structure which employs such a stress transmission device, and to a method of constructing such a structure. In the figures, a pile head member is provided to the pile head of the foundation pile , a structure support member is fixed to an upper structural portion , and these mutually contact one another in the vertical direction via a first contacting surface which defines a portion of a first imaginary spherical surface Sv . And a prestressing steel rod is fitted to the pile head member and the structure support member for holding them together in contact while pressing them together via the first contacting surface

Stress transmission device, and structure and method of constructing the same

A pipe having a ridge on the spigot and a method of producing such ridge. A ring having a circumferentially disposed split or splits is fitted in an annular groove formed in the outer periphery of the spigot, with the diameter of said ring being adjusted according to the tolerance of the outer diameter of the pipe. A pair of thin-walled portions formed on the circumferentially opposite ends of the ring defining the split are connected together by a connector or connectors operated from the outer peripheral side of the ring.

Pipe having ridge on spigot and method of forming the ridge

A separation preventive pipe joint is provided. A locking ring provided on an inner periphery of a socket is engaged with a projection formed on an outer periphery of an end portion of a spigot to prevent the spigot from being separated from the socket. When the spigot is to move deeper in the socket, a sleeve provided inside the socket abuts the end of the spigot to prevent the movement of the spigot. The movement of the spigot may otherwise be prevented by locating a deeper end face of the socket adjacent to the projection of the spigot. The projection fills up a clearance between the outer periphery of the spigot and the inner periphery of an open end portion of the socket, thereby preventing the spigot and the socket from bending relative to each other. The clearance may otherwise be filled up by means of a ring disposed on the inner periphery of the socket and bolts to be screwed into the socket from the outer periphery thereof to press the ring against the outer periphery of the spigot.

Separation-preventive pipe joint

A separation preventive pipe joint is provided, in which a locking ring is held by an elastic ring with its axis centered in a locking ring receiving groove. An outer peripheral projection is formed on an end portion of the spigot, the outer peripheral projection being engageable with the locking ring from a location deeper than the locking ring. An inner peripheral projection is formed in an inner peripheral portion of the socket which is located deeper than the locking ring receiving groove for backing up the locking ring. A first inner peripheral surface having a larger diameter than the inner peripheral projection is formed in an inner peripheral portion of the socket which is located deeper than the inner peripheral projection. A second inner peripheral surface is formed between the first inner peripheral surface and the inner peripheral projection, the second inner peripheral surface being larger than the inner peripheral projection and smaller than the first inner peripheral surface in diameter.

Growing community of inventors

Maebashi, Japan

Takahiro Ishihara