JPS62175783A - Optical scanning type electrophotographic recording device - Google Patents

Abstract

PURPOSE:To prevent an optical image formation system from being stained and to perform excellent recording stably for a long period by providing a developer removing means between the optical image formation system and a photosensitive body. CONSTITUTION:An image forming element 4 is put in an optical scanning unit 12 and the photosensitive body 2 is stored in an electrophotographic unit 13 while sandwiched between a developing device 5 and a cleaning device 8. Then, the optical scanning unit 12 and an electrophotographic unit 13 are covered with housings 14 and 15 respectively and an air flow is taken in or discharged from the part between the housings 14 and 15 as shown by an arrow to form an air curtain 11. Consequently, even if dust of a developer, etc., is scattered around the photosensitive body 2, the dust is cut off by the air curtain 11 and prevented from being stuck on the optical image formation system.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to an optical scanning electrophotographic recording device, and in particular, the present invention relates to an optical scanning type electrophotographic recording device, and in particular, an optical signal corresponding to image information emitted from minute light emitting segments is transferred onto a photoreceptor by an imaging optical system. The present invention relates to an optical scanning type electrophotographic recording apparatus that performs predetermined recording by forming and projecting an image on the image.

(Prior Art) In recent years, optical scanning electrophotographic recording devices have been developed to meet the demands for improved print quality, smaller size, lower cost, and the like. In this optical scanning type electrophotographic recording device, first, an exposure beam modulated based on image information is emitted from a light source, and this exposure beam is equipped with an imaging element such as a Selfoc lens array or a roof mirror lens array. A dot-shaped image is formed on the surface of the photoreceptor by the imaging optical system. As a light source, a laser, an LED array, an LSC array, a phosphor dot array, etc. are used. The image dots on the photoreceptor surface are then scanned in a predetermined direction to form an electrostatic latent image.
Predetermined recording is performed by developing this electrostatic latent image with a developer and making it visible.

However, when an imaging element such as a SELFOC lens array or a roof mirror lens array is employed as the imaging optical system as described above, the imaging optical system is installed extremely close to the photoreceptor. When the imaging optical system is installed close to the photoreceptor, dust such as particulate developer scattered near the photoreceptor may adhere to the imaging optical system. If such dust adheres, the imaging element etc. will be optically contaminated, leading to a reduction in light conduction efficiency and uneven exposure energy, resulting in problems such as uneven image density and background staining. Such defects become more noticeable as the device is used for a long period of time, so maintenance such as cleaning must be performed without fail, which is troublesome.

(Objective) An object of the present invention is to provide an optical scanning type electrophotographic recording apparatus that can prevent contamination of an imaging optical system and perform stable and good recording over a long period of time.

(Structure) In order to achieve the above object, the present invention includes a powder removal means that protects the imaging optical system from adhesion of dust such as developer, between the imaging optical system and the photoreceptor. This ensures that the imaging optical system is always kept optically clean.

Embodiments of the present invention will be described in detail below with reference to the drawings.

First, the general configuration of an optical printer using a phosphor dot array tube will be described as a specific example of an optical scanning electrophotographic recording apparatus to which the present invention is applied. In FIG. 8, reference numeral 1 indicates a phosphor dot array tube. The segment electrodes are arranged in a direction perpendicular to the drawing. A photoconductive photoreceptor indicated by reference numeral 2 is drum-shaped and is rotated and conveyed in the direction of the arrow, and surrounded by a charger 3, an image forming element 4, a developing device 5,
A transfer device 6, a fixing device 7, a cleaning device 8, and a static elimination lamp 9 are provided.

The printing process is as follows.

While rotating the photoconductor 2 at a constant speed in the direction of the arrow, the charge 17-3 first makes the circumferential surface uniform. ! Make it electric. Next, the phosphor dot array tube 1 is driven based on the image information, the image information is converted into an optical signal (phosphor screen emission), and this is transmitted to the imaging element 4 (e.g. Selfoc lens array or roof mirror lens array). The image is projected onto the photoreceptor 2 to form an electrostatic latent image. This electrostatic latent image is visualized by a developing device 5, the resulting visible image is electrostatically transferred onto a transfer paper S by a transfer device 6, and fixed by a fixing device 7. On the other hand, the photoreceptor 2 after the visible image has been fixed is cleaned by a cleaning device 8 and then discharged by a discharge lamp 9.

In the embodiment shown in FIG. 1, an air curtain 11 is formed between the imaging element 4 and the photoreceptor 2 as dust removal means. The imaging element 4 is housed in an optical scanning unit 12, and the photoreceptor 2 is housed in an electrophotographic unit 13 so as to be sandwiched between a developing device 5 and a cleaning device 8. The optical scanning unit 12 and the electrophotographic unit 13 are mounted in a housing 14.
and 15, and the above-mentioned air curtain 1 is
1 is formed. This air curtain 11
The air flow forming the photoreceptor 2 is passed over the surface of the photoreceptor 2 in the feeding direction.

The airflow can be formed by driving various fans and the like provided inside the machine.

As the fan, one for preventing the temperature inside the machine from rising or one for discharging 03 to the outside of the machine can be adopted.

In addition, the housing 14.1 of each unit 12.13 mentioned above
Each of the housings 5 is integrally made of a synthetic resin material or the like, and an air flow passage is easily formed by each of these housings 14 and 15.

In the apparatus having such a configuration, since the air curtain 11 is formed between the imaging element 4 in the optical scanning unit 12 and the photoreceptor 2 in the electrophotographic unit 13, the air around the photoreceptor 2 is Even if dust such as developer is scattered, the dust is blocked by the air curtain 11 from the imaging element 4 of the optical scanning unit 12 and will not reach the imaging optical system. As a result, dust is prevented from adhering to the imaging optical system. Then, the fine particles are carried away from the optical scanning unit 12 by the air flow of the air curtain 11.

In the embodiment shown in FIG. 2, an air curtain 22 is formed inside the optical scanning unit 21.

This air curtain 22 is formed by guiding airflow in the direction of the arrow into an air passage 24 provided along the inner wall of the housing 23.

In this way, if the air flow is made to flow inside the optical scanning unit 21, the air curtain 22 as a zero-removal means can be used.
In addition to forming a micro light emitting segment array, the air flow can also cool the IC for driving the micro light emitting segment array at the same time.

In this case, it is preferable to provide an independent fan to forcefully circulate the airflow.

In the embodiment shown in FIG. 3, an air curtain 32 is formed on the electrophotographic unit 31 side. This air curtain 32 is formed by guiding air flow in the direction of the arrow into an air passage 34 provided along the inner wall of the housing 33 of the electrophotographic unit 31.

In this case, the air flow forming the air curtain 32 can effectively prevent the temperature of the photoreceptor 2 from rising and prevent 03 from staying.

In each of the embodiments described above, reinforcing effects and rectifying effects can be obtained by providing partitions, folds, etc. at predetermined intervals at the inlet or outlet of the air flow forming the air curtain. Furthermore, the speed of the air flow does not need to be high; it is sufficient that an air curtain is substantially formed.

Further, in the embodiment shown in FIGS. 4 and 5, a cover body 41 is provided so as to be in sliding contact with the surface of the imaging element 4 facing the photoreceptor 2 side. This cover body 41 is installed so as to be moved back and forth in the feeding direction of the photoreceptor 2, and has an optical path 42 formed in its center.

By reciprocating the cover body 41, the exposure beam from the imaging element 4 passes through the optical path 42 during recording (Fig. 4), and is blocked by the main body of the cover body 41 during non-recording (Fig. 4). Figure 5). This prevents the powder layer around the photoreceptor 2 from adhering to the imaging element 4 side during non-recording.

Further, a cleaning member 43 that comes into contact with the imaging element 4 is provided on the main body portion of the cover body 41 . This cleaning member 43 is made of felt.

It is made of a flexible member such as a sponge or a brush, and the imaging element 4 is cleaned by moving this member while contacting the imaging element 4.

Even with such a configuration, the imaging element 4 can always be maintained in an optically clean state. Note that the cover body 41 in this embodiment can conveniently function as a light shielding member for preventing flare. Furthermore, the optical path 42 may be configured to be closed during non-recording.

In the embodiments shown in FIGS. 6 and 7, the entire imaging optical system including the imaging element 4 is rotated by a predetermined angle by an autorotation mechanism. During recording, the exposure beam from the imaging element 4 is irradiated onto the photoreceptor 2, and during non-recording, the imaging element 4 itself rotates and moves away from the photoreceptor 2.

This prevents dust around the photoreceptor 2 from adhering to the imaging element 4 side during non-recording.

In particular, if the force bar unit 51 is installed on the side of the imaging element 4 as in this embodiment, a sufficient dust blocking effect can be obtained.

Further, in this embodiment, as in the above embodiments, a cleaning member 52 is provided which comes into contact with the imaging element 4 and cleans it during non-recording. This cleaning member 52 allows the imaging element 4 to be maintained in an optically clean state at all times.

In the above-mentioned two embodiments, it is not necessary to always keep the imaging element 4 in a light-shielding state during non-recording, and it is sufficient to perform the light-shielding operation and cleaning operation only during a predetermined period of time before and after the power is turned on and off. It is.

(Effects) As described above, the optical scanning photographic recording device according to the present invention has an imaging optical system installed between a photoreceptor and an imaging optical system that exposes the photoreceptor to a developer, etc. Since a private removal means is installed to protect the camera from adhesion of private materials, the imaging optical system can always be kept in an optically clean state, resulting in good recording without uneven image density or background stains. I can make you do it.

[Brief explanation of drawings]

FIG. 1 is an explanatory longitudinal cross-sectional view of an apparatus in one embodiment of the present invention, FIGS. 2 to 7 are explanatory longitudinal cross-sectional views of an apparatus in other embodiments of the present invention, and FIG. 8 is an explanatory longitudinal cross-sectional view of an apparatus in another embodiment of the present invention. FIG. 3 is a vertical cross-sectional view showing main parts. 2... Photoreceptor, 4... Imaging element, 11, 22.32
... Air curtain, 12.21 ... Optical scanning unit, 13.31 ... Electrophotography unit, 14.15゜2
3.33... Housing, 41.51... Cover body, 42... Optical path, 43.52... Cleaning member.

Claims (1)

[Claims] 1. An electrostatic latent image is formed by projecting an optical signal corresponding to image information emitted from a minute light emitting segment onto a photoreceptor using an imaging optical system, and this electrostatic latent image is In an optical scanning type electrophotographic recording device that performs predetermined recording by developing and visualizing images with a developer, an imaging optical system is provided between the imaging optical system and the photoreceptor. What is claimed is: 1. An optical scanning type electrophotographic recording device, characterized in that it is equipped with a dust removal means for protecting the dust from adhering to agents, etc. 2. The optical scanning electrophotographic recording according to claim 1, wherein the developer removing means is constituted by an air curtain formed between the imaging optical system and the photoreceptor. Device. 3. The optical scanning electrophotographic recording according to claim 1, wherein the developer removing means is constituted by a cover body provided to cover the surface of the imaging optical system on the photoreceptor side. Device. 4. The optical scanning electrophotographic recording apparatus according to claim 1, wherein the developer removing means comprises a cleaning body for cleaning the surface of the imaging optical system on the photoreceptor side. 5. The scanning electrophotographic recording apparatus according to claim 1, wherein the developer removing means is constituted by an autorotation mechanism of an imaging optical system.