JPH01114869A - Image forming device - Google Patents

Abstract

PURPOSE:To prevent laser beams from leaking, which may affect the unloading of a laser leaking part or related operation, by providing a shutter member blocking laser beams from a laser scanning optical system by means of interlocking with the move of a movable member. CONSTITUTION:The laser scanning optical unit 2 is arranged in the innermost recess of a main body 1. The shutter 3 opening and closing a laser emitting port 2a is arranged at the front of the unit 2. When a main body front door 1a is opened in response to the opening and closing of the door 1a to handle jammed paper or replace parts, the laser emitting port 2a is closed. On the other hand, when the door 1a is closed, the emitting port 2a is opened. For the shutter 3, a scraping member 4 adheres to the surface facing a transparent resin plate 11, and when the shutter 3 is opened and closed, the scraping action is performed on the exposed surface of the resin plate 11. Thus, the leakage of laser beams can be surely prevented, and simultaneously losses of laser beams caused by toner, etc., can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image forming apparatus such as a laser beam printer.

[Conventional technology]

The photoconductive layer is charged around the photoreceptor having the photoconductive layer on its surface, and an electrostatic latent image is formed by exposing the photoconductive layer to light signals corresponding to an image. toner)
An image forming apparatus that supplies a latent image to make the latent image a focal point, brings a transfer material such as plain paper close to the image, transfers it, and repeats the process after cleaning the photoreceptor. It has been widely put into practical use.

In such image forming apparatuses that use a scanning optical system that uses a laser as the light source for exposure, when replacing paper jams or parts, it is necessary to open the microswitch by opening the main body cover. Safety devices that stop laser emission using electrical means are generally known. On the other hand, the laser scanning optical system prevents the toner particles and dust floating in the image forming apparatus from entering the optical system.
In order to prevent such adhesion, it is generally known that a dust-proof glass or an optical system that also serves as a dust-proof glass is disposed at the exit port of the laser beam.

[Problem that the invention seeks to solve]

However, with the above-mentioned safety devices, laser light is emitted even when the main body cover is opened and parts are replaced due to a malfunction or failure of a switch, and there is a risk that this laser light may leak out of the device. . On the other hand, in the scanning optical system described above, toner and dust may adhere to the surface exposed inside the dust-proof glass device, and if left unused for a long period of time, it may cause transmission loss of laser light and seriously affect print quality. was there. Additionally, in order to prevent this, cleaning means by the device user may be considered, but this increases maintenance work and increases complexity.

In view of the above-mentioned problems, the present invention blocks the optical path of the laser beam in response to attaching/detaching parts that may cause laser beam leakage, such as opening a cover, or a series of related operations. Provided is an image forming apparatus that can reliably prevent light from leaking to the outside and at the same time automatically clean the surface of a dust-proof optical member of a laser scanning optical system to prevent loss of laser light due to toner or the like. The purpose is to

[Means for solving problems]

The image forming apparatus according to the present invention includes a shutter member that shuts off the laser beam of the laser scanning optical system in conjunction with the movement of the movable member, and the image forming apparatus of the laser scanning optical system that is interlocked with or integrated with the shutter member. The device is characterized by having a wiping member that moves over the surface of the optical member exposed within the device.

[For production]

According to the present invention, the shutter member installed in front of the laser exit port of the laser scanning optical system shuts off the laser in conjunction with the opening of a movable member such as the front door of the image forming apparatus main body. , the wiping member that can prevent laser leakage to the outside of the device and that is interlocked with or integrated with the shutter member slides the surface of the optical member disposed at the laser exit port when the shutter member is opened and closed. By moving the optical member, it is possible to automatically prevent loss of laser light due to adhesion of toner or dust on the surface of the optical member.

〔Example〕

FIG. 1 shows a side view of a laser printer to which the present invention is applied. There is a polygon mirror 2 on the back side of the main body 1 (on the right side in the figure).
b, a laser scanning optical unit 2 including a lens 2c, a mirror 2d, etc. is arranged, and a laser beam exit 2 of the unit is arranged.
A has a transparent resin plate 11 (for example, polycarbonate, PM
MA, etc.) are placed to prevent toner, dust, etc. from entering the unit. On the front side of the optical unit 2,
A drum-shaped photoreceptor 5 is arranged, and a charger 6, a developer 7, a transfer device 8, a cleaning station 10, and the like are arranged around it.

Now, the image signal corresponding to the information from the scanning optical unit 2 is exposed to the surface of the photoreceptor 5 uniformly charged by the charger 6 through the transparent resin plate 11 of the laser exit port 2a of the unit 2, and the surface of the photoreceptor 5 is uniformly charged by the charger 6. An electrostatic latent image is formed, and then this latent image is visualized by a developing device 7 and is transferred by a transfer device 8 onto a transfer material (not shown) fed by a paper feed roller 15 in the direction of arrow A. The transfer material carrying this toner image is sent downward in the figure, and is moved to the fixing roller 9a.
The paper is fixed at a fixed volume by a head fixer 9 made of a sn paper roller 8b, etc., and then discharged to the outside of the main body 1. It is assumed that the toner that did not contribute to the transfer in the transfer process is removed from the photoreceptor 5 by the cleaning device 10, and then the above-described image forming process is repeated.

In this embodiment, a shutter 3 for opening and closing the laser exit port 2a is disposed on the front surface of the scanning optical unit 2, and the door is opened in response to opening and closing of the main body front door 1a when processing paper jams or replacing parts. When this happens, the laser exit port 2a is closed, and when the door is closed, the laser exit port 2a is opened. On the other hand, a wiping member 4 (for example, felt cloth material, etc.) is bonded to the shutter 3 on the surface facing the transparent resin plate 11, and wipes the exposed surface of the resin plate 11 when the shutter is opened and closed. perform an action.

FIG. 2 shows the configuration of the shutter 3 and the wiping member 4 and their operating states. As shown in FIG. 2(a), the front surface of the scanning optical unit 2 has a laser exit port 2a.
A long shaft 3 for opening and closing is engaged with guide paths 14 formed at both ends of the front surface of the unit, and is slidably disposed along the front surface. In addition, the other end of a spring 13 whose one end is attached to an immovable part such as the case of the optical unit 2 is locked to the shaft 3, and the spring 13 has a tendency to move in the direction of closing the laser exit port 2a as shown in FIG. 2(C). It is attached. Furthermore, the opposite side of the locking portion of the spring 13 of the shutter 3 is connected to the link mechanism 12 via the node portion 12a, and the other end of the link mechanism is connected to the optical unit 20 case via the node portion 12c. It has been stopped. Figure 2(b)
As shown in , when the front door 1a of the main body is closed, the node 12b is pushed by the claw 1b protruding from the door, and the shutter 3 is moved through the link mechanism 12 against the action of the spring 13. When pulled in the direction of arrow B, the laser emission port 2a becomes open and laser emission becomes possible. Now, the door 1a
When the person becomes open-deaf, the claw portion 1
b moves away from the node 12b, and the link machine t'1i12 is opened, so the shutter 3 closes the laser exit port 2a in the direction of arrow C by the action of the spring 13, thereby preventing leakage of the laser.

On the other hand, the wiping member 4 attached to the surface of the shutter 3 facing the transparent resin plate 11 slides on the exposed surface of the transparent resin plate 11 in conjunction with the opening and closing of the shutter 3, that is, the opening and closing of the front ffi 1a of the main body. automatically removes toner and dust attached to exposed surfaces. - When fishing on a boat, the front door 1a of the main body is opened and closed regularly for maintenance and inspection and troubleshooting, so the exposed surface of the transparent resin plate 11 is also cleaned regularly, which prevents loss of laser light. .

In this embodiment, a transparent resin plate is used as the dustproof member, but it goes without saying that an optical member that also serves as a dustproof member, such as a long cylindrical lens, may also be used. The material may also be glass, and in the case of resin, applying a hard coat treatment (such as a polyfunctional acrylate ultraviolet curing method) to the surface can prevent surface abrasion due to contact with the wiping member. can.

〔Effect of the invention〕

As described above, according to the present invention, the optical path of the laser beam is blocked in response to the attachment/detachment of parts where the laser beam may leak, such as opening the cover, or a series of related operations. leakage to the outside can be reliably prevented, thereby allowing the user to extremely safely replace paper jams and drums during printing. At the same time, the surface of the dust-proof optical member of the laser scanning optical unit is automatically cleaned to prevent loss of laser light due to toner, etc., thereby saving the user the trouble of periodic work and cleaning the surface uniformly. Since it can be wiped off, it was possible to provide an image forming apparatus that can produce uniform and good printed matter over a long period of time.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an embodiment of the image forming apparatus of the present invention. FIGS. 2(a) to 2(C) are diagrams that do not show a more detailed configuration and each operating state of the above embodiment of the present invention. 2...Laser scanning optical unit 3...Shutter 4...Wiping member 5...Photoreceptor 11...Transparent resin plate 12...Link mechanism 13...Spring Applicant: Seiko Epson Agent Co., Ltd. Patent attorney Tsutomu Mogami and 1 other person

Claims (3)

[Claims] (1) An image forming apparatus that uses a laser scanning optical unit as an optical signal generating device and uses an electrophotographic process, including a shutter member that shuts off the laser beam of the laser scanning optical unit in conjunction with the movement of a movable member. An image forming apparatus characterized by: (2) Image formation according to claim 1, further comprising a wiping member that moves on a surface of an optical member disposed at a laser exit of the laser scanning optical unit that is exposed to the outside of the unit. Device. (3) The wiping member is interlocked with or integrated with the shutter member.
The image forming apparatus described in .