摘要:
A cleaning device for a dry electrophotographic device includes a cleaning brush brought into resilient contact with an object to be cleaned such as a photosensitive drum. A cleaning roll rotates while constantly being brought into contact with the cleaning brush and a cleaning blade is pressed against the cleaning roll to clean the cleaning roll. A rotation direction switching mechanism switches the rotation direction of the cleaning brush such that the rotation direction of the cleaning brush when cleaning the object, for example, during the formation of an image, is different from that when the brush is not cleaning the object.
摘要:
Disclosed is a second toner developing apparatus for use in a two color electro-photographic recording apparatus in which a photosensitive drum is uniformly charged, subject to a first exposure, developed with a first toner, subject to a second exposure, and then developed with a second toner. The second developing apparatus is provided with a rotary sleeve for performing magnetic brush development and a fixed magnet disposed within the rotary sleeve. The fixed magnet includes a plurality of magnetic poles of the same polarity provided close to each other, so as to temporarily separate the second developer from the surface of the rotary sleeve at the position of these same polarity magnetic poles. An electrostatic attraction electrode attracts the first toner mixed in the thus separated second developer to thereby remove the first toner from the second developer.
摘要:
A laser beam printer comprises a single scanner deflecting a plurality of laser beams for the purpose of scanning, a laser beam position detector detecting the position of one of the deflected laser beams, and a plurality of delay circuits determining the recording starting timing of the plural laser beams in response to the output signal from the laser beam position detector. The surface of a photosensitive drum is scanned with the plural laser beams to sequentially form a plurality of electrostatic latent images corresponding to a plurality of predetermined colors respectively, and the latent images are sequentially developed with a plurality of color toners during one rotation of the photosensitive drum. The color toner images are simultaneously transferred onto a recording sheet to obtain a record printed in plural colors.
摘要:
A developer level sensor installed on the sidewall of a developer container in a developing apparatus consists of an oscillator circuit with multiple coils, the mutual inductance of which is adjusted by a moveable electric conductor. The lower limit level of developer sensed may be adjusted by the positioning of a control plate.
摘要:
In an image forming apparatus, the absolute value (.vertline.VBH-VM.vertline.) of the potential difference between a first development bias electric potential (VBH) and an intermediate electric potential (VM) is set to be smaller (.vertline.VBH-VM.vertline.
摘要:
The present invention provides a development apparatus capable of improving the development pole of a plurality of development rolls and the rotation speed thereof, thus obtaining stable printing quality. A first development roll rotatable in the opposite direction to the moving direction of photosensitive body is disposed in the upstream of it, whereas a group of second development rolls are disposed in the down stream, which development rolls are rotatable in the same direction as the moving direction of photoconductive body and have magnets of the same polarity. The first development roll and the photoconductive body define a peripheral speed ratio ranging from 0.5 to 1.5, while allowing the second development roll and the photoconductive body to define a peripheral speed ratio ranging from 0.6 to 1.5. A development control member is provided between the first development roll and the group of second development rolls. A toner density detector is provided in the downstream of the last one of the group of second development rolls which is disposed in the most significant downstream. A cross mixer and a carrier member are also provided under the first development roll and the group of second development rolls.
摘要:
In an electrophotograpic recording apparatus, a charge supply unit and a light erasing unit are disposed in the stated order when viewed in the direction in which a photoreceptor rotates, at a location between a transfer unit and a bias cleaning unit, and light from the light erasing unit is projected onto a photoreceptor surface area except the charge supplied area. A developing apparatus of the type in which a cleaner section for removing and collecting residual toner on a photoreceptor is coupled through a toner transport pipe with a toner hopper of a developing unit, wherein a meshed foreign material collector, which may be vibrated, is disposed at a location in a residual toner collecting path ranging from the cleaner section, the toner transport pipe, and the toner hopper.
摘要:
In a multi-stage roll magnetic brush type of developing device, at least two opposite direction rotation rolls which rotate in an opposite rotation direction to that of a photosensitive body are arranged adjacently and oppositely to a photosensitive body, and at least one same direction rotation developing roll which rotates in the same rotation direction as that of the photosensitive body is arranged adjacently, oppositely to the photosensitive body and upstream of the opposite direction rotation developing rolls in the rotation direction of the photosensitive body. Thus, the path of carrying the developer by the same direction rotation developing roll and the opposite direction rotation developing rolls can be optimized. In the wide area printing at high speed, an image with stabilized printing quality can be obtained without an increase in the production cost.
摘要:
A scanning recording type printing method, in which sampled image of tone data is printed by controlling the scanning length and position of a dot which may include a plurality of different colors in the interior of a pixel such that the dots in two adjacent pixels are paired such that no interruptions exist between the dots.
摘要:
In an electrophotographic recording method in which electric charge is uniformly applied to the surface of a photoconductive drum, the drum surface is then exposed to a first information light beam to form a first negative latent image, the first negative latent image is developed with a first two-component developer, the drum surface is further exposed to a second information light beam to form a second negative latent image, and the second negative latent image is developed with a second two-component developer to produce a two-color toner image, the toner content in the second two-component developer is larger than that in the first two-component developer.