Minolta Camera Kabushiki Kaisha

Hirohisa Miyamoto

Kenzo Nagata

Keiji Kusumoto

Kazuhiro Araki

Naoyoshi Kinoshita

Kaoru Hashimoto

Hiroyuki Hanamoto

Takashi Onishi

Keiji Yoshida

Yasuyuki Matsuuchi

A copying machine with plural developing units being capable of performing at least one edition mode and a simultaneous multi-mode in which the developing unit is switched from one to another on the way through one copying action is disclosed. In the simultaneous multi-mode, the position at which the developing unit is to be switched is designated by a position designation device such as keys provided on an operation panel and/or an editor, if connected to the copying machine. In this case, only one coordinate of the designated position in the sub-scan direction is employed to designate the switching position for the developing unit.

Copying machine operable in simultaneous multi-color mode

A document size detection device comprising an illuminating unit for irradiating a first light on a document on a platen; a projecting unit for projecting the first light reflected on the document onto a photosensitive member; a document cover for covering the document on the platen, the cover having a reflecting area for reflecting the first light from the illuminating unit and a non-reflecting area for transmitting the above light; a document detection sensor provided at a position corresponding to the non-reflecting area and comprising a light emitting element and a light receiving element; and a filter for transmitting a second light from the light emitting element as well as guiding the first light from the illuminating unit to the projecting unit, the filter unit being opposed to a detecting surface of the sensor.

Document size detection device

A document detecting device for an image forming apparatus operates when a sensor supporting arm equipped with sensors is pivoted to a predetermined position below a document, the document size or the density of the image is detected by the combination of the detection results of the sensors. One of the combinations which is not used for the document size or density detection is used to detect that the sensor supporting arm is at its original position. This construction avoids such an error that the sensor supporting arm is misinterpreted as being at its original position when an irregular sized document is set. When a new document is set, the data indicating the previous document size is accurately updated by the combined use of two switches. The first switch detects whether a document holding cover is opened less than a predetermined angle. The second switch detects whether the cover is completely closed. Thus, any potential errors which may occur when a new document is set by opening the cover less than the predetermined angle can be avoided.

Document detecting device for an image forming apparatus

The image forming apparatus includes first developing unit, a unit mounting portion, a detecting apparatus, input apparatus and a mode controller. Either an outline forming unit or a second developing unit for developing a latent electrostatic image is mounted on the unit mounting portion. The detecting apparatus detects which of the outline forming unit and the second developing unit is mounted on the mounting portion. The input apparatus selects one of an outline forming mode, a first developing mode and a second developing mode. The mode controller controls the first and the second developing unit and the outline forming unit according to any of the modes based on the information from the detecting apparatus and the input apparatus. The mode controller can select either the outline forming mode or the first developing mode when the outline forming unit is detected by the detecting apparatus. The mode controller can select either the first developing mode or the second developing mode when the second developing unit is detected by the detecting apparatus.

Image forming apparatus for forming outline and normal images

An image forming apparatus which, when a trouble is detected, discriminates between a minor trouble and a serious one which may cause a high extent of damage and puts a copying operation in an inoperative state, so that in case of the minor trouble a first reset switch operable by an operator is operated to release the inoperative state and in case of the serious trouble a second reset switch operable by a maintenance staff is operated to release the inoperative state so as not to allow the operator to release the inoperative state caused by the serious trouble, thereby preventing aggravation of damage caused by the trouble.

Image forming apparatus with one reset switch for resetting one type of

A copying machine which includes several developing units adapted to accommodate respective masses of powdery developers of different colors; a specifying unit for specifying a position, which will constitute the boundary of a copying area, in a direction conforming to the direction of scan of a scanning system; a copying contorl unit for selectively switching and driving the developing units in correspondence with the position of the boundary of the copying area specified by the specifying unit, so as to accomplish a multi-color copying during one cycle of copying operation, and an eraser for erasing a predetermined range in the scanning direction in reference to the position of the boundary of the copying area specified by the specifying unit.

Multi-color copying machine

The apparatus includes a photosensitive drum, a charger for charging the drum, a plurality of developing devices, selecting switch for selecting one of the developing devices to be used and controller for controlling the output of the charger so as to elevate the surface potential of the drum by a predetermined potential corresponding to the selection by the selecting switch, said predetermined potential being equal to a decay potential occurring while the surface of the drum rotates from the position opposed to the charger to the portion opposed to the selected developing device.

Image forming apparatus having a plurality of developing devices

Three mounting portions are provided along a direction of rotation of a photoreceptor with an eraser lamp and a corona charger provided on the upstream side of the mounting portions. A first developing unit, an outline unit and a second developing unit, each of which can be attached to and detached from each of the mounting portions, are mounted in this order from the upstream side. When an outline mode is selected, colors of the developing units mounted on the downstream side of the outline unit are displayed on a display portion. When there is no developing unit on the downstream side, no color is displayed, and the copying operation in the outline mode is prohibited. If there is only one developing unit on the downstream side, the copying operation is started by pressing a copying key. If there are a plurality of developing units on the downstream side, a plurality of colors are displayed, and the copying operation is prohibited until one of those colors is designated.

Copying apparatus capable of forming various types of images

An image duplicating apparatus having optical scanning and image reproducing stages for reproducing images on a sheet medium, a plurality of sheet feeding stages each for feeding a sheet medium to the image reproducing stage, the sheet feeding stages being respectively operative to store sheet media of different sizes, a first size indicating device for indicating the size of the sheet media stored in each of the sheet feeding stages, a first controller for controlling the optical scanning and image reproducing stages so that the image reproducing stage reproduces images on one of the opposite faces of a sheet medium fed from one of the sheet feeding stages, a sheet recovery and supply stage for temporarily storing the sheet medium having images reproduced on one of its faces under the control of the first controller and thereafter supplying the sheet medium for a second time to the image reproducing stage, a second controller for controlling the optical scanning and image reproducing stages so that the image reproducing stage reproduces images on the other face of the sheet medium supplied from the sheet recovery and supply stage, a second size indicating device for indicating the size of the sheet media which can be stored in the sheet recovery and supply stage, and a sheet-feed selecting device for comparing the sizes of sheet media respectively indicated by the first and second size indicating device and automatically selecting the particular one of the sheet feeding stages that stores sheet media of the size identical with the size of sheet media indicated by the second size indicating device.

Image duplicating apparatus having plural copying modes and plural sheet

An illuminating device for image exposure in an electrophotographic copying machine, which employs a fluorescent lamp whose voltage is variable as an illumination source and has signals to indicate when the copying machine is ready to make copies and to tell when the light amount for illumination is insufficient after preliminary lighting being performed for a fixed amount of time. A temperature sensor to detect tube wall temperature of the fluorescent lamp and a light sensor to detect the amount of light emitted from the lamp installed in the device to permit the preliminary lighting of the fluorescent lamp to be carried out at an appropriate voltage. Therefore, clear copies are readily made soon after the power of the copying machine is turned on, and, electric power waste and/or serious troubles of the machine which may occur by further use as well as exhaustion of the lamp by unnecessary high voltages can be avoided.

Growing community of inventors

Osaka, Japan

Hirohisa Miyamoto