Asahi Kogaku Kogyo Kabushiki Kaisha

Tsukasa Yanashima

Tomoyuki Nishikawa

Tsutomu Sato

Hiroyuki Saito

Masatoshi Takano

Kasumi Yamamoto

Hiroyuki Yamaguchi

Yutaka Ishikawa

Masakazu Hirano

Yoshio Monma

Tsutamu Sato

A printer has one or more fans in the vicinity of a fixing device to blow air directly onto a continuous form when printing is stopped and when rollers in the fixing device are separated. The fan or fans can be provided on a pressure roller side of the continuous form, in which case the continuous form shields a heat roller from the air flow of the fans. In the alternative, the fan or fans can be on the heat roller side, in which case a shield extending along the circumference of the heat roller, duct, or both is used to protect the heat roller from the air flow and/or the continuous form from direct heat radiation. A pair of rollers are disposed downstream of the fixing device and are rotated while the continuous form is stopped so as to maintain tension on the continuous form.

Sheet drying prevention device

A fixing unit, used for fixing images on a recording sheet, includes a heat roller accommodating a heater, and a press roller movable between a retracted position and an operating position. The heat roller is rotated by a driving mechanism. A moving mechanism opens and closes a gap between the press roller and the heat roller by moving the press roller between the retracted position and the operating position. An assist gear rotates the press roller in a predetermined direction when the opening/closing mechanism moves the press roller toward the operating position.

Fixing unit

In a continuous form printer, a passage of the leading edge of the sheet is detected by a top sensor located along a feeding path thereof. If the top sensor detects the leading edge of the sheet while the sheet is fed in a reverse direction, the control unit of the printer determines whether the detection of the leading edge by the top sensor is correct or not, by feeding the sheet once in the forward direction and then feeding the sheet in the reverse direction and by checking whether the top sensor again detects the leading edge of the sheet being fed in the reverse direction.

Sheet feeding system including leading edge detection

A fixing unit includes a heat roller accommodating a heater and a press roller movable toward and away from the heat roller. Both shaft members of the heat roller are supported by two receiving members, with a clearance provided between each shaft member and respective receiving member. A driven gear is provided to one of the shaft member, which engages a rotating mechanism for rotating the heat roller. The fixing unit further includes a biasing member which biases the other shaft of the heat roller away from the press roller within the clearance, in such a manner that the heat roller and the press roller become parallel when the above-described one shaft member is urged away from the press roller due to the meshing engagement of the driven gear and the rotating mechanism.

A fixing unit includes a heat roller accommodating a heater and a press roller movable between an operating position in which the recording sheet is nipped by the rollers and a retracted position. A driven gear is provided to one axial end of heat roller, which engages a rotating mechanism for rotating the heat roller. An opening/closing mechanism is arranged to move a first axial end (at the same side as the driven gear of the heat roller) of said press roller to said operating position before moving a second axial end of the press roller to the operating position.

Fixing unit having press roller opening/closing mechanisms

A temperature controlling device for an electrophotographic imaging device which has a fixing unit including a heat roller, the fixing unit performing a fixing operation in which toner is fixed on a recording sheet. The temperature controlling device includes a temperature sensing system, arranged about an outer surface of the heat roller such that, for the purpose of temperature measurement, the heat roller is divided into a plurality of areas along a rotational axis of the heat roller, and a temperature of each area is detected by the temperature sensing system; an air blowing system which blows air to each of the plurality of areas separately; and a controller which controls the air blowing system to blow air in accordance with temperatures of the plurality of areas in order to prevent overheating of any portions of the heat roller.

Temperature controlling device for fixing unit

A charge removing member is arranged just upstream of an image transfer area along a continuous form transport path, between the last guiding portion and the transfer area, to remove accumulated charge on the continuous form. The charge removing member is alternatively a brush contactable to the form, a non-contact conductive member, a brush movable toward and away from the form, or a brush that acts as a guide member. Further alternatively, the brush contacts the form only during reverse feeding of the form, and in this case, is alternatively movable toward and away from the form, movable toward and away from the form in association with a transfer unit, or positioned to contact a straight form while being out of contact with a form bent by a transfer unit.

Charge removing device for electrophotographic printer

A continuous form electrophotographic printer is provided with a guiding member upstream of a photoconductive drum. The electrophotographic printer retracts paper after it has once passed a fixing unit and been heated, and the guiding unit is provided with an urging member to smooth distorted or wrinkled paper.

Continuous form printer with paper guide mechanism

An electrophotographic printer includes a fixing unit having a movable pressure roller, movable toward and away from a heat roller. The heat roller of the fixing unit is above a plane formed between a pair of discharge rollers and a tractor, so that the paper path between the tractor and the discharge rollers is straight when the pressure roller is retracted, and the paper path is bent when the pressure roller is moved to contact the heat roller. The paper path is bent by a guide member upstream of the pressure roller so that the path is not bent around the pressure roller itself.

Growing community of inventors

Tokyo, Japan

Tsukasa Yanashima