Matsushita Electric Industrial Co., Ltd.

Masaya Shimada

Tadayuki Kajiwara

Yuzo Kawano

Seiichiro Hiratsuka

Naoki Yamaguchi

Tomoyuki Noguchi

Junichi Tanizaki

Yuji Toyomura

Yoshiaki Ijima

Kazuhiko Soeda

Kazuhiko Tajima

Jun-ichi Tanizaki

Yuhzou Kawano

Jun'ichi Tanizaki

Kohei Suyama

Naomi Uchida

Yuhzoh Kawano

Akira Sadamoto

In a toner image forming apparatus, a contact member for pressing a work piece at a pressing position against a toner image on a movable transfer member so that the toner image is transferred from the transfer member onto the work piece is pressed against the transfer member while a test pattern toner image which is prevented from being transferred onto the work piece moves from a transfer position at which the toner image and the test pattern toner image are transferred onto the transfer member and a detecting position at which the test pattern toner image is detected to obtain a difference between the test pattern toner image on the transfer member and a desired test pattern image.

Image forming apparatus having test pattern transfer prevention control

An image forming apparatus includes an image carrier, a driving unit for transmitting a driving force to the image carrier via a driving spline, and a plurality of members to be driven for driving the driving force transmitted from the driving unit via the image carrier. A shaft is disposed coaxially with a rotation shaft of the image carrier in one end of the image carrier. An involute spline-shaped follower spline to which the driving force is transmitted from the driving unit via the driving spline is formed on an inner peripheral surface of the flange, and a driving force transmitter for transmitting the driving force to at least one of the member to be driven is formed on an outer peripheral surface of the flange.

Image forming apparatus

A color-image forming apparatus minimizes displacement in toner images due to irregularities in the thickness of an inter-stage transfer belt. The pattern detector detects a registration reference pattern formed on the belt. Accepting information on displacement over one cycle of travel of the belt from the pattern detector, the displacement amount calculator detects information on displacement in a print range which the toner images formed in a plurality of image-forming stations are transferred thereto. The displacement amount calculator then calculates a mean value of displacement in the range. The central processing unit (CPU) controls the image-forming timing determined by a plurality of exposure units, according to the result calculated by the displacement amount calculator.

Color-image forming apparatus

An image formation apparatus comprises photosensitive drums for respectively forming toner images corresponding to specified colors of an original image, an intermediate transfer belt onto which the toner images are transferred from the photosensitive drums in superimposed relation to form a synthetic toner image, and transfer rollers each for pressing the intermediate transfer belt against the associated photosensitive drum. The photosensitive drum disposed more upstream in a direction of conveyance of the intermediate transfer belt has a lower speed. The intermediate transfer belt may be designed to move at a speed higher than those of the photosensitive drums. With this construction, a sag or dip of the intermediate transfer belt between any two adjacent photosensitive drums is eliminated, thereby preventing a color drift of the synthetic toner image.

Color image formation apparatus using plural photosensitive drums

A registering pattern having a predetermined configuration for each color is formed on a transfer material, and color misregistering is detected and corrected by laser beams and a photosensor.

Color image forming apparatus

An exposure apparatus is set to each color so that latent-image lines formed on photosensitive drums,to,have predetermined inclinations from rotation axes of the photosensitive drums,to,to form electrostatic latent images on the photosensitive drums,to,while performing curve correction on the photosensitive drums,to,. Peripheral speeds of the photosensitive drums,to,are controlled so that inclinations of toner images of a plurality of colors on an intermediate transfer belt become equal to each other. Thereby, each pixel is not shifted when light-scanning images are superimposed each other by the exposure apparatus,and it is possible to obtain a high-quality image free from image deterioration due to scanning irregularity caused by inclination shifts of scanning lines,K,,C,,M, and,Y.

Multiple-image forming apparatus capable of correcting color shifts

An image reader, which is capable of reading tone effects of a document precisely and can be miniaturized, includes a document glass, a light source for illuminating the document, an optical system for image formation of a reflected light from the document, an image reading section, a carriage, a driving motor for driving the carriage, a vertical scanning white reference board disposed outside an area, in which the document is mounted, within a range of reading and at least arranged apart from the carriage in a direction toward the document glass, a vertical scanning shading correction arrangement for correction to keep an image signal level at a constant level, and a locating section for locating a position in a horizontal scanning direction of the vertical scanning white reference board, whereby tone effects of the document can be read precisely and the image reader be miniaturized.

Image reader

In a color separating device, three reflection elements each formed by laminating a dichroic mirror and a total reflection mirror via a transparent layer interposed therebetween are used. The three reflection elements have mutually different spectral characteristics and are arranged to separate incident light reflected from a color original into three color lights without causing a difference in optical paths of the respective color lights. Two of the reflection elements may be used in combination with a condenser lens having principal points whose positions differ depending on wavelengths of light, so as to perform the three-color separation in a similar manner.

Growing community of inventors

Onojo, Japan

Masaya Shimada