Brother Kogyo Kabushiki-Kaisha

Terumasa Ito

Tomitake Aratachi

Yasuo Tamaru

Sakae Ito

Shusaku Tsusaka

Takahiro Ikeno

Masatoshi Shiraki

Fumitake Tajiri

Masaki Yasuda

In an image forming apparatus, a temperature of a heating member heated by a heat source to fix a developer image on a recording sheet is detected by a temperature sensor disposed apart from the heating member. A controller controls the heat source based upon a temperature determined mathematically by application of a specific function to the temperature detected by the temperature sensor. In the controller, the specific function is switched among a plurality of functions according to a control mode which is switchable among a plurality of modes and in which operation of the heat source is regulated.

Image forming apparatus with a temperature sensor  disposed apart from a heating member

In a printer, a scanner unit is formed into a taper shape having a thinner thickness on a side of a pick-up roller in a removing direction of a process unit, to allow the process unit to be removed from the printer. A part of a sheet feeding path is formed in an area between the process unit and a sheet cassette. An image forming position on the sheet feed path is set lower than an upper end of the pick-up roller. Thus, removal of the process unit can be readily performed. Further, the height of the printer at a position of the pick-up roller can be reduced as compared with a case where the scanner unit is not formed into a taper shape.

Image forming apparatus having lowered image forming position and recessed sheet stacking portion

A fixing unit of an image-forming device having a heating roller, a pressure roller disposed in confrontation with the heating roller, and a case that rotatably supports the heating roller on both longitudinal ends thereof and covers the heating roller from the side opposite the pressure roller, while leaving the pressure roller exposed. A pair of pressure roller support plates, one end of which is supported on the case, rotatably supports both ends of the pressure roller. With this construction, a more compact fixing unit can be achieved than when the case is configured to cover the heating roller and pressure roller entirely. The fixing unit includes a temperature fuse for restraining abnormal temperature rises in the heating roller, and a temperature fuse cover that extends from an inner wall of the case to provide insulation between the temperature fuse and the heating roller. By integrally forming the temperature fuse cover with the case, it is possible to reduce the manufacturing costs of the fixing unit. Support members may also be provided between a bottom surface of the case and the temperature fuse cover to restrain deformation of the temperature fuse cover.

Fixing unit having heater roller and pressure roller supports and image-forming device using the same

A fixing unit is disposed at a position closer to a rear side wall than to a front side wall of a casing. A top wall is formed with a depressed portion depressed toward inside the casing. The depressed portion serves as a sheet discharge tray for receiving a recording medium that has passed through the fixing unit. The sheet discharge tray includes a tray member detachably disposed at the top wall. The rear side wall is formed with an opening through which the fixing unit is removed. When the tray member is disposed at the top wall, the tray member is positioned above and adjacent to the fixing unit and overlaps the fixing unit when viewed through the opening, thereby preventing the fixing unit from being removed from the casing. The fixing unit is removable through the opening when the tray member is detached from the top wall.

Image forming device and fixing unit

An image forming apparatus includes a main casing; a photosensitive member; a process cartridge that can be installed or removed with respect to the main casing along a removal path; a pick-up roller located above a sheet accommodating portion; and a feed path along which a sheet can be conveyed from the sheet accommodating portion to a discharge port. At least a part of the feed path is substantially parallel to the removal path and located between the sheet accommodating portion and the process cartridge when the process cartridge is installed in the main casing; and an image forming position where an image is transferred from the photosensitive member to the sheet is located along the feed path at a position lower than an upper surface of the pick-up roller in a verticle direction.

A plurality of helical groove sections are provided on outer peripheral surfaces of press rollers provided in a curl elimination mechanism. Each of the groove sections assumes a shape extending in the circumferential direction of the respective press rollers; that is, a direction oblique to a transport direction of paper. Hence, when compared with a case where the groove sections are aligned in the transport direction of the paper, the paper is less susceptible to traces of the groove sections. Since the groove sections are provided on the press rollers, an attempt can be made to enhance dimensional accuracy of or reduce the weight of the press rollers.

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Ama-gun, Japan

Terumasa Ito