JPS60120385A - Supporting device for image carrier belt - Google Patents

Abstract

PURPOSE:To prevent toner from scattering by preventing oscillations of a beltlike photosensitive body by plural support rollers and a contat member. CONSTITUTION:A front cover 15, internal upper cover 16, internal rear cover 17, and internal lower cover 18 are arranged for a photosensitive body 8 between rollers 4 and 7 opposite the internal surface of a plane part. The internal front cover 15 covers the photosensitive body 8 to the overall width of the internal surface. The respective internal covers 15-18 are provided with a shield member 20 of ''Teflon'' felt, etc., which is flexible and constitutes the contact member having high wear resistance upon occasion by adhesion at positions facing both end parts of the internal surface of the image carrier belt 8, and this shield member 20 contacts the circumference of the internal side end part of the image carrier belt 8 lightly.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides image information converted into electrical signals that is output from a computer, image reading device, etc., or a latent image corresponding to an original image obtained using electrophotography. An image display device that carries an image as a toner image on an image carrier on an endless belt and reproduces it as it is, or an image forming device such as a copying machine that has the function of further transferring the image visualized on the belt to a transfer paper or the like. The present invention relates to an image carrying belt supporting device. Generally, an image display device or an image forming device having an endless image carrying belt as described above has a structure in which the image carrying belt is mounted on a plurality of rollers and rotated. Such an image carrying belt has toner attached to its surface and rotates within the main body of the apparatus, so that the toner on the image carrying belt is easily scattered inside the apparatus. When such scattering of toner occurs within the apparatus main body, various parts inside the apparatus are contaminated with toner, causing various problems.

For example, if toner adheres to optical parts such as lenses, it will have a fatal effect on the original functions of the device, and if toner is conductive, it will scatter onto electrical parts, causing accidents such as short circuits. occurs. Furthermore, if toner gets into the mechanical parts, it may no longer function normally. As described above, toner is a powder, and it penetrates deep into complex mechanical parts, and once it has penetrated deep, it is not easy to clean it.

Particularly in devices using an image bearing belt as described above,
If the toner adheres to the back surface of the belt, since the back surface of the belt is the surface that comes into contact with the roller, the toner will be caught between the roller and the belt and adhere to the roller surface or the back surface of the belt, damaging the image bearing belt. Furthermore, if the belt continues to rotate with toner adhered to the back surface of the image carrying belt, the toner will fly up in the space surrounded by the endless image carrying belt, causing the above-mentioned problems in various parts of this space. . Generally, the inner surface of the image bearing belt is difficult to clean unless the belt is removed from the apparatus, making cleaning work difficult.

Further, since the image carrying belt is suspended and supported by a plurality of rollers as described above, the portion stretched between the rollers is likely to vibrate. When the belt is used in a display device, this vibration not only makes it difficult to see images on the display unit, but also becomes one of the major causes of scattering the toner adhering to the belt.

In view of the above points, the main object of the present invention is to prevent toner from scattering in a space surrounded by an image carrying belt. Another object of the present invention is to provide an image bearing belt suspension and support device that prevents belt vibration and prevents toner from scattering.

The image bearing belt support device of the present invention that achieves the above object includes:
It has a plurality of support rollers that tension and support an endlessly moving image carrying belt carrying a toner image on its outer surface, and a contact member that is provided between the rollers and contacts both sides of the inner surface of the image carrying belt. .

Hereinafter, the present invention will be explained according to one embodiment.

FIG. 1 shows an external view of an image display device to which the present invention is applied, FIG. 2 is a partially perspective sectional view thereof, and FIG. 3 is a side sectional view thereof.

In the figure, 1 is an exterior cover, 2 is a transparent display glass provided on the front of the exterior cover, and 3 is an operation panel provided on the front protrusion of the cover, which performs image processing such as calling up image information and giving instructions to the display device. Do the following.

An image forming section is built inside the exterior cover 1.

This image forming section includes a drive roller 4, support rollers 5, 6 .
7 A belt-backed photoconductor 8 which is an image carrier stretched by these rollers, a semiconductor laser oscillator 9 provided inside the photoconductor 8, a scanner 10 which is a laser scanning device, an fθ lens 11, and a mirror. 12 for writing the latent image, and a developing device 13 provided outside the photoreceptor 8 in the exposure section.

A motor (not shown) is connected to the rear end shaft of the drive roller 4, and conveys the belt-covered photoreceptor 8.

Further, at least one of the support rows 25, 6.7 (the support row 25 is preferable in the illustrated example) is movable in the radial direction, and applies a predetermined tension to the photoreceptor 8 using a spring or the like to cause it to wave. It is configured to provide a tension of 4 to prevent sagging and slipping between the photoreceptor 8 and the drive roller 4.

The belt-backed photoreceptor 8 is, for example, one side of a transparent polyester sheet (in the configuration of this example, the outer side of the stretched track).
A conductive metal is deposited very thinly on the surface, and Cd is then deposited on the surface.
It is formed by applying a photosensitive material such as S.

Further, in the exposure area where a latent image is formed on the photoreceptor 8 by the laser beam irradiated onto the photoreceptor 8 through the mirror 12, a support roller 6 is placed in contact with the inner surface of the photoreceptor 8 in the non-light area. A protective glass 14 is provided at a position slightly protruding from the common tangent line of . This is to prevent the vertical vibration of the photoconductor 8 caused by the vibration, maintain the exposure position constant, and improve the resolution. When the laser beam is emitted, the laser beam passes through the scanner 10, the fθ lens 11, and the mirror 12, and is irradiated onto the photoreceptor 8 in the exposure section. It is visualized.

As the photoreceptor 8 moves in the direction of arrow A, the image formed on the outer peripheral surface of the belt-shaped photoreceptor 8 is carried to a position facing the display glass, and is temporarily stopped for display. . Thereafter, the image that has finished displaying is sent to the exposure section again by the movement of the photoreceptor 8, and immediately after being cleaned by a developing brush, a new image is formed through the processes of exposure and development.0 The above-mentioned image display device The image forming process in JP-A No. 58-98746 or JP-A-Sho 58 by the applicant of the present application is
Those disclosed in Japanese Patent Application No. 57-151278 and Japanese Patent Application No. 57-151278 can be used, and their explanation will be omitted here.

The image carrier used in the image carrier belt support device of the present invention applied to the apparatus having the above configuration will be explained with reference to FIGS. 4 and 5.

FIG. 4 is a cross-sectional side view of the vicinity of the photoreceptor 8, which is an image bearing belt, and FIG. 5 is a perspective view of the vicinity of the rollers 4 and 7. In the figure, each roller 4, 5, 6 .
A front inner cover 15. is located at a position facing the inner surface of the flat portion between 7 and 15. Upper inner cover 16. A rear inner cover 17 and a lower inner cover 18 are arranged. For example, the front inner cover 15 covers the entire inner width of the photoreceptor 8 as shown in FIG. 5, and its side portions are fixed to both side plates (not shown). The other inner covers 16, 17, and 18 are also fixed across the side plates in the same way as the front inner cover 15. In addition, the lower inner cover 18 has a fourth slit 19 on the optical path of the laser beam.
The opening is perpendicular to the plane of the figure. Furthermore, each of the inner covers 15, 16, 17, 18 is made of flexible material such as Teflon felt, and has high abrasion resistance as required. The shield member 20 is attached to a position opposite to both ends of the inner surface of the image carrying belt 8, and this shield member 20 is in light contact with the vicinity of the inner end of the image carrying belt 8. Photoreceptor 8
Most of the portions that are not in contact with the eyelets 4, 5, 6, and 7 are in contact with the shield portion 20. For this reason, each roller 4,
Vibration in the area between 5 and 6.7 almost no longer occurs, and toner scattering due to vibration of the photoreceptor 8 also almost no longer occurs. Further, since both sides of the inner surface of the photoconductor 8 are in contact with the shield member 20, and furthermore, there are inner covers on the outside of the photoconductor up to the position of the side plates (not shown), so that toner is transferred to the photoconductor 8.
The amount of toner that wraps around the back side of the photoreceptor 8 from the sides of the photoreceptor 8 is significantly reduced, and the amount of toner scattered into the internal space surrounded by the photoreceptor 8 is significantly reduced. As a result, the above scanner 10°fθ
Almost no toner adhered to the optical system such as the lens 11 and mirror 12. Further, since the photoreceptor 8 is in contact with the shield member 20, the flatness of the photoreceptor in the image displaying portion 21 is improved, resulting in the effect that the image is easier to see.

FIG. 6 is a partially cutaway perspective view of another embodiment of the shield member which is the contact member of the present invention.

In the above embodiment, felt was used as the shield member 20, but in addition, the shield member 20 shown in FIG.
A member having soft synthetic bristles 23 planted on the surface of the band film 22 such as & is used, and the inner surface of the photoreceptor 8 is brought into contact with the bristles 23.

FIG. 6(b) shows a flexible member such as felt or urethane, or an elastic member 2 such as rubber as the shield member 20b.
The same effect as described above was also obtained by adhering a protective member 25 having good abrasion resistance, such as Teflon tape, to the surface of photoreceptor 4 and bringing this protective member 25 into contact with the inner surface of photoreceptor 8.

FIG. 1 is a partially cutaway perspective view of a shield member 20c in still another embodiment of the contact member of the present invention.

In this embodiment, the shield member 20c is made of an elastic member such as urethane rubber or Moltoprene, or a low-friction member such as Teflon or polyacetal, and a plurality of grooves 27 are formed on the surface 26 that contacts the inner surface of the photoreceptor 8. It has been established. This groove 27 has the effect of stopping toner entering from the contact surface between the shield member 20c and the photoreceptor 8 at the protrusion of the surface 26, or scraping and capturing the toner. Therefore, the greater the number of grooves 27, the better the toner trapping effect.

By cleaning the toner captured in the groove 27 when the photoreceptor 8 is replaced, the trapping effect of the groove 27 is restored again.

In the embodiment shown in FIG. 7, the surface of the groove 27 is in surface contact with the photoreceptor, but the shape of the groove is a wave-shaped cross section or a triangular cross section parallel to the traveling direction of the photoreceptor 8, and the surface is in line contact with the photoreceptor. You can also get the same effect.

FIG. 8 is a partially cross-sectional perspective view showing still another embodiment of the contact member of the present invention, in which a surface 28 of the shield member 20d is provided with a positive polarity with respect to the traveling direction S, facing the end 8a of the photoreceptor 8. A groove 29 having an inclination is provided. One or both ends (not shown) of this groove 29 are closed. The primary role of grooves 29 is to trap toner that enters the inside of the photoreceptor. The second role is to apply a frictional force F along the inclination direction of the groove 29 to the mass point P of the photoconductor 8 that is in contact with the surface 28, and by the horizontal component F of this F, the photoconductor 8 is This improves flatness and at the same time prevents vibration of the photoreceptor.

Therefore, the characteristics of the groove 29 need only be to have a predetermined angle in the direction defined by the traveling direction of the photoreceptor, and the above effect can be achieved even if the groove has a round shape with both ends closed.

FIG. 9 is a perspective view showing a modification of the method of supporting the shield member 20, in which a left front inner cover 15a and a right front inner cover 15b are provided in place of the front inner cover 15 of FIG. 5, and both front inner covers 15a are provided. .

15b and each shield member 20 is bonded to the shield member 15b.

Even in this configuration, the shield member 20 and the front inner covers 15 m + 15 on both sides are provided on the outside of the side end of the photoreceptor 8.
Since b is provided, it is possible to prevent toner from entering the back surface of the photoreceptor 8.

In this way, each inner cover 15. t6. The members 17 and 18 do not need to cover the entire width of the photoreceptor 8, and may be members that cover at least both sides of the photoreceptor 8 to the side plates.

Although the present invention is extremely effective in the image display device as described above, the present invention can be directly applied to an image forming device such as a copying machine as described above. 1 shows a schematic configuration of an embodiment in which the present invention is applied to a copying machine.

To briefly explain the configuration of the illustrated copying machine, an original 41 placed on an original platen glass 40 is exposed to a flash light source 42.
The reflected image is projected through a lens 43 onto a belt-type photoreceptor 44 consisting of a conductive substrate and a photoconductive layer on the surface.

This belt type photoreceptor 44 is connected to a drive roller 47. Tension roller 45. To the transfer roller 46! It has been supported extensively.

On the other hand, the belt-type photoreceptor 44 before entering the exposure area is prepared to form a static latent image by a cleaning device 50 and a charger 51. Then, a static latent image is formed by projecting the original image in the exposure area, the latent image on the photoreceptor 44 is visualized by a developing device 52, and the toner image is transferred onto copy paper 53.

In the apparatus having the above configuration, the belt-folded photoreceptor 44
An inner cover 54 is provided on the flat portion between the rollers 45, 46, and 47 at a position facing the back surface of the image bearing surface.
A shield member 20 is adhered to the inner cover 54 as in the above embodiment, and a belt-type photoreceptor 4 is provided.
It is lightly touching the back side of 4.

The above configuration suppresses vibrations of the belt-laying photoreceptor 44, and furthermore, since the image exposure surface is supported flatly, toner scattering is prevented and the original image can be exposed with high accuracy, resulting in improved image quality. was also obtained.

As described above, the present invention is extremely effective in image forming apparatuses such as copying machines that use an image bearing belt such as a photoreceptor, and its usefulness is great. In addition to the photoreceptor, the image bearing belt may be a well-known insulating belt that forms a latent image using a multi-stylus.

[Brief explanation of the drawing]

FIG. 1 is an external perspective view of an image display device to which the present invention is applied;
Fig. 2 is a partial cross-sectional perspective view of the same device, Fig. 3 is a cross-sectional side view of the same device, Fig. 4 is a photoconductor view, and Fig. 7 is a perspective view of a modification of the supporting force type of the contact member. 8 shows the present invention, 4, 5, 6.7...roller, 8...photosensitive member which is an image bearing belt, 20.20a, 20b. 20c, 20d...shield member , 44... Indicates the photoreceptor belt. e81 7° 2° iZ6 -

Claims (2)

[Claims] (1) In a device for supporting an endlessly moving image carrying belt carrying a toner image on its outer surface, a plurality of support rollers that support the image carrying belt in tension, and an inner side of the image carrying belt provided between the rollers. An image carrying belt support device comprising: a contact member that contacts both end portions of a surface. (2) The image carrying belt support device according to claim 1, wherein the contact member has an uneven surface whose angle θ with the traveling direction of the image carrying belt is 0≦θ<900. .