Kyocera Mita Corporation

Mita Industrial Co., Ltd.

Yutaka Aso

Masayuki Kakuta

Kuniaki Araishi

Hiroshi Kobayashi

Jun Kusakabe

Shigeo Kurando

Masahide Inoue

Masaki Deguchi

Mamoru Kato

Takeshi Arakawa

Ryo Fujisawa

Koji Murata

Hideki Kitagawa

Koichi Tsuyama

Masaki Degichi

Kazuyoshi Osawa

A projecting tab formed with a bulged portion and an indent on an upper side thereof is provided inwardly projecting in a transport path. A sheet being transported in the transport path is formed into a seemingly wavy configuration in the width direction of the transport path while in contact with the projecting tab. The sheet thus formed with the seemingly wavy configuration is given with a sufficient transport backup force in a transport direction, thereby being hard to bend in the transport direction. Thus, the sheet supplied with the sufficient transport backup force is free from a curled lead end, folded or bent corner lead end of the sheet in the transport direction, and sheet jam. The arrangement of the projecting tab securely accomplishes sheet transport in a desired transport direction without a possibility of sheet transport failure.

Sheet transport device

A sheet transport device is provided with a sheet inverting mechanism for retracting a sheet transported along a main transport route into a switchback route to invert the sheet transport direction and returning the sheet into the main transport route to turn the side of the sheet. The sheet transport device has a pair of sheet guides adapted in contact with respective opposite ends of the sheet set on a sheet setting portion to prevent a skew transport of the sheet. The sheet temporarily brought onto the sheet setting portion during a switchback operation from the switchback route is guided between of the sheet guides on the sheet setting portion. During the temporal appearance on the sheet setting portion, the opposite ends of the sheet are aligned by the respective sheet guides. Thereby, securely prevented is an occurrence of a skew transport state of the sheet during the switchback operation.

Sheet transport device and automatic document feeder

In a paper transport device, a first roller serving as a separation roller is situated underneath a second roller serving as a document feed roller, together forming a roller pair. A rotary shaft of the separation roller is biased upward toward the document feed roller by means of an elastic element. One end of the rotary shaft is connected to a drive shaft via a coupler while a connecting bar is joined to the other end of the rotary shaft obliquely from above. An extreme end of the connecting bar opposite to the rotary shaft is attached to a support plate fixed to a main body of the paper transport device in such a way that the connecting bar can swing about pivot pin fixed to the support plate. In the paper transport device thus constructed, one end of the rotary shaft fitted to the coupler acts as a point of support, allowing the other end of the rotary shaft to move downward overwhelming an upward-lifting force of the elastic element when forced downward by the connecting bar. In this construction, the separation roller can be separated from and brought into contact with the document feed roller.

Paper transport device with one roller pair

A sheet transport device is provided with a sheet inverting mechanism for performing a switchback operation in which a sheet transported along a main transport route enters a switchback route, and the sheet transport direction is inverted in the switchback route to return the sheet to the main transport route so as to turn the side of the sheet. A registration roller pair is disposed near the junction between the main transport route and the switchback route. The sheet inverting mechanism is operated in such a manner that the sheet transport is temporarily suspended until a skew correctable portion that enables correction of a skew transport state of the sheet is formed at a lead end of the sheet in the exiting direction from the switchback route after the lead end of the sheet comes into contact with the registration roller pair. Thus, the skew transport state of the sheet which is liable to occur during the switchback operation is corrected.

The present invention relates to a recycle developing process which comprises developing an electrostatic image formed on a photosensitive material with a starting developer filled in a developing vessel, transferring the toner image to a predetermined paper, recovering the toner remaining on the photosensitive material by a cleaning means, and repeating the developing procedure while replenishing a virgin toner and the toner recovered by the cleaning means into the developing vessel; wherein the virgin toner to be replenished into the developing vessel is that which is fulfilled in a container wherein a rotating roller is provided in an opening portion at a lower portion has a flowability, shown as a fallen amount of the toner at a time of falling via the rotating roller for a certain fixed time, of 50 to 70% based on the toner in the starting developer. According to this process, an abrupt decrease in the properties of the developer due to the mixing of the recovered toner can be relaxed. As a result, a stable image free from fogging or toner scattering can be formed by the recycle developing process.

Recycle developing process

A recycle developing method utilizes the steps of (1) providing a developing vessel containing a starting developer composed of an electroscopic toner and a magnetic carrier; (2) transferring toner from the developing vessel to a photosensitive material having an electrostatic latent image formed thereon; (3) transferring a portion of the toner on the photosensitive material to a paper to form a toner image on the paper; (4) recovering toner remaining on the photosensitive material after the aforementioned portion of toner is transferred to the paper to form a toner image thereon; and (5) repeating steps (2)-(4) while replenishing toner in the developing vessel by the sub-steps of: (5a) supplying toner recovered in step (4) to the developing vessel, and (5b) supplying a virgin toner, having a higher chargeability than the electroscopic toner in the starting developer, to the developing vessel, to form a mixed toner in the developing vessel. An absolute value of the average charge quantity of the mixed toner is greater than the absolute value of the average charge quantity of the electroscopic toner in the starting developer plus 10 .mu.C/g. Apparatus to effect the process is also disclosed.

Recycle developing method and apparatus

A developing method using a compact machine such as a copying machine for personal use, etc., employs a two component-type magnetic developing agent with small diameter photosensitive drum and small diameter developing sleeve. In order to eliminate toner falling from the drum and/or sleeve to increase toner transfer efficiency and reduce fogging, the developing agent conveying sleeve is provided with a curvature (mm.sup.-1) of from 0.2 to 0.05. The toner is specifically designed for use in the method and includes magnetic fine particles having a saturation magnetization of not smaller than 70 emu/g and hydrophobic fine silica particles added to fixing resin particles containing a coloring agent.

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Osaka, Japan

Yutaka Aso