Sharp Kabushiki Kaisha Corporation

Hiroshi Kida

Toshiaki Kagawa

Takashi Yamanaka

Tetsunori Mitsuoka

Yoshiaki Masuda

Hirokazu Yamauchi

Syoichiro Yoshiura

Takahiro Fukunaga

Tatsuya Inoue

Kiyohide Ochi

Norio Hontani

Masanori Takeda

Masanori Kato

Masanobu Deguchi

Toyoaki Nanba

Yoshiharu Yoneda

Koji Wakamoto

Yuji Okamoto

Kazuhiro Matsuyama

Masashi Hirai

Masaru Tsuji

Junya Masuda

Masahiko Fujita

Shoichiro Yoshiura

Kazuo Nakamura

Tadasu Taniguchi

Shinichi Takeda

Tatsuya Shinkawa

Hideki Ohnishi

Kimihito Yamasaki

Masanobu Yamamoto

Masao Matsui

Masaru Nishijima

Ken-ichi Iwamoto

Kouji Yamaji

Yukio Nakai

Tutomu Kato

Kouichi Matsumoto

An image recording system is configured in which a plurality of image recording apparatuses provided with a recording medium storage portion are disposed in a line, and a recording medium storage means shared by these image recording apparatuses is provided, and a recording medium that has been recorded by the plurality of image recording apparatuses is transported toward the recording medium storage means and stored in the recording medium storage means.

Image recording system

A control section () includes a first power control section () (a first power control mode) and a second power control section () (a second power control mode). The first power control section () is for controlling an setting value of electric power to be supplied to a heater lamp () based on the temperature of a heating roller (). The second power control section () is for controlling the setting value of electric power to be supplied to the heater lamp () in order to forced-drive the heater lamp () by an electric power that is higher than the setting value of electric power. Switching control means () performs switching between the first power control mode and the second power control mode depending on a status of operation of each of components forming an image forming apparatus ().

Power control method for controlling a setting value of electric power to be supplied to each of components of an apparatus by switching between power control modes depending on a status of operation of each of the components of the apparatus

The present invention is made to provide a pretransfer charging device, which allows (i) reduction of generation of discharge products such as ozone and nitroxide, (ii) excellent uniform charging, (iii) continuous stable charging for a long period of time, and (iv) restraint of distortion of a toner image. The pretransfer charging device includes (i) ion generation needles each provided face to face with an image carrier such as a photoconductor drum or an intermediating transfer belt, and (ii) a high-voltage power supply for applying a negative voltage to each of the ion generation needles. The voltage to be applied from the high-voltage power supply is not less than an ion production threshold voltage but is less than a corona discharge threshold voltage. With this, no corona discharge occurs but negative ions can be generated. This makes it possible to solve various problems caused due to the corona discharge.

Pretransfer charging device and image forming apparatus including same

An image forming device includes a first carriage path for carrying paper stored in a paper feeding tray to a printer, there is a second carriage path for carrying paper stored in a second paper feeding tray to the printer. The first carriage path and the second carriage path individually carry a paper to the printer.

Image forming device

A fixing device () of the present invention includes a fixing roller () contacting a toner image surface, and a pressure roller () contacting a surface opposite to the toner image surface. In the fixing device (), a printing sheet (P) on which unfixed toner image is formed passes through a fixing nip portion (Y) where the fixing roller () and the pressure roller () are in contact with each other, so that the above-described toner image is fixed on the printing sheet (P). The fixing device () further includes a control circuit () which controls heater lamps (to) so that a surface temperature of the pressure roller () is in a temperature range defined by a cold offset occurring boundary temperature (Thc) of the fixing roller () and/or a hot offset occurring boundary temperature (Thh) of the fixing roller (). With this, it is possible to suppress or prevent a transfer of toner to a pair of rollers (a transfer from the back of the printing sheet to the pressure roller, a transfer from the pressure roller to the fixing roller).

Fixing device and fixing method and image forming device

A fusing device () has heat reflectors () and () positioned in consideration of the fact that convective heat loss from respective outer surfaces of the heat reflectors () and () depends on orientation of the outer surfaces. More specifically, each of the heat reflectors () and () are positioned so as to have a convective heat transfer coefficient &#x3b7; of up to 0.9. The convective heat transfer coefficient &#x3b7; is given by the following expression:&#x3b7;=(0.770.54)/(),were Su is a projected area of an outer surface of each of the heat reflectors on an upper horizontal plane, Sh is a projected area of the same on a vertical plane, and Sd is a projected area of the same on a lower horizontal plane.

Heating device

A fixing device includes a fixing member in contact with an unfixed image constituted of developer T on one side of a recording material P; and a pressure member pressed against the fixing member. The fixing device fixes the unfixed image onto the recording material P by causing the recording material P, charged so as to have a same polarity as a polarity of the developer T, to pass through a gap between the fixing member and the pressure member. In the fixing device, an inflow current into the fixing member Ih is 0 when the recording material P passes through the gap between the fixing member and the pressure member. This securely restrains the developer on the recording material from electrostatically offset to the side of the fixing device, thereby maintaining the formation of high quality images.

Fixing method, fixing device, and image forming apparatus

A fixer (heater) includes a heat roller and a pressure roller pressing each other. The fixer heats a heated material by passing the heated material through a press region where the heat roller and the pressure roller meet. The fixer further includes an external heat roller heating the pressure roller from outside the pressure roller. A transit time taken for any given point on the heated material to pass through the press region is less than or equal to 2.3&#xd7;10sec. The surface temperature, T(&#xb0; C.), of the heat roller and the surface temperature, T(&#xb0; C.), of the pressure roller satisfy T-T&#x2266;100 (&#xb0; C.), and preferably satisfy T-T&#x2266;70 (&#xb0; C.). The load on the heat roller is reduced, and so is the power consumption.

Heater, and image forming apparatus, heating method incorporating same

A fixer (heater) includes a heat roller and a pressure roller pressing each other. The fixer heats a heated material by passing the heated material through a press region where the heat roller and the pressure roller meet. The fixer further includes an external heat roller heating the pressure roller from outside the pressure roller. A transit time taken for any given point on the heated material to pass through the press region is less than or equal to 2.3&#xd7;10sec. The surface temperature, T(&#xb0; C.), of the heat roller and the surface temperature, T(&#xb0; C.), of the pressure roller satisfy T&#x2212;T&#x2266;100 (&#xb0; C.), and preferably satisfy T&#x2212;T&#x2266;70 (&#xb0; C.). The load on the heat roller is reduced, and so is the power consumption.

A fixing device cleaning device, provided on a fixing device having a heating member and a pressing member pressed against the heating member at a predetermined contact pressure, comprises a cleaning member, formed in a scraper shape, which is pressed against the heating member, or the pressing member, so as to remove developer from a surface of the heating member or the pressing member. The cleaning member includes one or more opening sections in a vicinity of a contact point with respect to a cleaning target surface of the heating member or the pressing member.

Fixing device cleaning device and image forming device

The invention provides a fixing unit including a fixing roller and a pressure roller pressed against the fixing roller inside a housing, for holding and conveying a sheet carrying an image formed by a developer between the fixing roller and the pressure roller thus to fix the image onto the sheet, including a removal section that removes an unfixed developer adhered to the fixing roller or the pressure roller, and an air vent located close to the removal section.

System for collecting an unfixed developer with an airflow

An image forming apparatus includes an image recording device and a recording material supply device, and an external recording material supply device is connected to the recording material supply device in parallel. In a main body of the recording material supply device, a space is formed between the inner wall on a peripheral equipment connecting side and a longitudinal transport path so as to allow the longitudinal transport path to open from a front side of the recording material supply device. The longitudinal transport path is provided for transporting the recording material from the recording material supply device to the image recording device.

Image forming system and image forming apparatus being configured for easy removal of jammed recording material and for reducing installation space

An embodiment of a screw conveyor includes a rotating shaft and a conveying blade helically formed around and loosely coupled with the rotating shaft. One or both of two edges of the conveying blade is/are only fixed to the rotating shaft, and a gap is provided between the rotating shaft and the conveying blade. Thereby, the conveying blade can be vibrated in a center axis direction of the rotating shaft by rotation of the rotating shaft and conveyed waste developer.

Screw conveyor and developer conveying mechanism

Within a fixing roller () are disposed a main heater lamp () for heating a central portion of the fixing roller and a sub-heater lamp () for heating opposite end portions of the fixing roller. MRnh, SRnh and &#x3a3;Rnh satisfy the formula (1) or (2):&#x3a3;&#x2267;30.5&#xb7;()+382&#x2003;&#x2003;formula (1)&#x2266;&#x2212;21.9&#xb7;()&#x2212;198,&#x2003;&#x2003;formula (2)where MRnh is a mean value of heat distribution in a no-heat generating section of the main heater lamp; SRnh is a mean value of heat distribution in the a no-heat generating section of the sub-heater lamp; &#x3a3;Rnh is the sum total of these mean values; and Ht=vp/(Mh&#xb7;&#x3bb;) where vp is a fixing speed (m/s), Mh a heat capacity per unit length of the heating member (J/(&#xb0; C.&#xb7;m)) and &#x3bb; a heat conductivity of a material forming the heating member (W/(m&#xb7;&#xb0; C.)).

Heating device and image forming device

A fixing device comprising a fix member for touching an unfixed image on a recording medium, and a press member for being pressed against the fixing member, so as to fix the unfixed image on the recording medium by transporting the recording medium through a nip between the fix member and the press member, wherein (100&#xb7;K)&#x2266;(K)&#x2266;(320&#xb7;K) where Kis a heat transmission coefficient of the press member and Kis a heat transmission coefficient of the fix member. With this arrangement, it is possible to transmit heat to toner and the recording medium in a short time. Thus, it is possible to attain high-speed printing.

Growing community of inventors

Yamatokoriyama, Japan

Hiroshi Kida