JP3762235B2 - Static eliminator - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to a static eliminator for neutralizing a transfer material onto which a toner image formed on an image carrier is transferred.
[0002]
[Prior art]
For example, in an image forming apparatus using an electrophotographic photosensitive member as an image carrier, first, the surface of the image carrier is uniformly charged by a charging device, and an electrostatic latent image is formed on the surface by a writing device. Next, the electrostatic latent image is developed by the developing device, and the developed image is transferred onto the recording material conveyed by the transfer device, and then the developed image is fixed on the recording material by the fixing device. Provided to the user as an image formed product.
[0003]
In order to stably convey the recording material from the transfer process to the fixing process, a neutralization device is provided on the downstream side of the transfer device so that the recording material after transfer is neutralized and reliably separated from the image carrier. It is configured. The static eliminator is generally provided with a static eliminating member that is formed in a pointed shape such as a needle shape or a saw shape and extends in the paper width direction in order to discharge the recording material in a non-contact manner by discharge. The part faces the back surface of the recording material at a predetermined interval.
[0004]
[Problems to be solved by the invention]
However, since the static eliminator is usually disposed at a position (process part) close to the image carrier, toner or the like scattered around the image easily adheres to the static eliminator, and the static eliminating action tends to decrease. Therefore, regular cleaning by a service person or the like is required. However, the neutralization member is sufficiently protected around the insulation member to prevent accidental contact and deformation of its shape, so that it cannot be easily cleaned. Many. Therefore, the cleaning has not been easy.
[0005]
In consideration of such a special structure of the static eliminator, the service man is instructed to wipe toward the tooth tip (pointed portion) of the static eliminator during cleaning. However, it is difficult to wipe, so if you do it, the wiping work will be performed in the longitudinal direction (paper width direction), the tooth tip will be deformed, and in the case of severe cases, a trouble will occur that the service person cuts the finger. There was also.
[0006]
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a static eliminator that can sufficiently protect the discharge tip electrode and is easy to clean.
[0007]
[Means for Solving the Problems]
In the present invention, means for solving the above-described problems are configured as follows.
[0008]
(1) A static eliminator provided on the downstream side of a transfer device for neutralizing a transfer material onto which a toner image on an image carrier is transferred and separating the transfer material from the image carrier.
The static eliminator is
A charge removing member having a large number of discharge tip electrode formed continuously at an equal pitch over the width direction throughout the direction of the transfer material, while supporting the discharge tip electrode, on the surface side than the thickness of the discharge tip electrode A plurality of protrusions, which are protruding protrusions and are located in all or part of the space between adjacent discharge tip electrodes, and have insulating members formed at equal pitches over the entire area in the paper width direction. Features.
[0009]
According to this configuration, by disposing the protrusion between the adjacent discharge tip electrodes so as to protrude from the thickness of the electrode, during the wiping operation, the discharge tip electrode is protected by the protrusion, and deformation, damage, etc. In addition, it is possible to effectively prevent the occurrence of troubles such as injury by pinching a finger between the discharge tip electrodes.
[0010]
(2) between the projections adjoining neighbors, characterized in that at least one discharge tip electrodes are positioned.
[0011]
According to this configuration, by disposing the discharge tip electrode between the projections, the discharge tip electrode can be protected by the projections, and deformation or breakage thereof can be prevented.
[0012]
(3) The insulating member is positioned closer to the transfer means than the static eliminator having the discharge tip electrode, and the projection of the insulating member is detachably provided to cover the discharge tip electrode. It protrudes toward the member side.
[0013]
According to this configuration, if the protective member is removed, the discharge tip electrode can be easily cleaned, and the discharge tip electrode can be protected by the protrusion, and its deformation, breakage, etc. can be avoided. .
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a static eliminator of an image forming apparatus according to an embodiment of the present invention will be described with reference to the drawings.
[0015]
FIG. 1 shows the configuration of an image forming apparatus (hereinafter referred to as “apparatus”) 1. The apparatus 1 has a paper feeding unit 2 at the bottom, and prints on paper fed from the paper feeding unit 2. The printed paper is configured to be discharged to the paper discharge unit 3 provided in the upper portion of the apparatus 1 with the image forming surface facing down. For this reason, the paper conveyance path 4 connecting the paper supply unit 2 and the paper discharge unit 3 is provided. , Extending in a substantially vertical direction upward from the lower part of the apparatus 1, and passes through the image forming unit 5 on the way.
[0016]
In the image forming unit 5, a charging device 7, an exposure device (laser scanning unit) 8, a developing device 9, a transfer device 10, a cleaning device 11, and the like are disposed around the photoreceptor 6. When the paper passes between the photosensitive member 6 and the transfer device 10 (transfer portion), the toner image formed on the photosensitive member 6 is transferred, and the paper on which the toner image is transferred is transferred to the paper conveyance path 4. The toner image is fixed by passing through the fixing unit 12 disposed downstream of the transfer unit. Reference numeral 13 denotes an externally attached paper reversing path for double-sided printing. In addition, the paper feeding unit 2 described above can optionally include a multistage paper feeding cassette on the lower side of the apparatus 1.
[0017]
In such an apparatus 1, the above-described transfer device 10 is provided with a neutralization device 15 for neutralizing the paper on which the toner image formed on the photoconductor 6 is transferred and separating the paper from the photoconductor 6. ing. First, as shown in FIG. 2, a transfer roller 23 that is urged to the photosensitive member 6 by a spring 22 is provided in the casing 21 of the transfer device 10 that is disposed in the paper feed width direction (perpendicular to the paper surface). The casing 21 is supported by the spring 24 in a biased state on the photosensitive member 6 side, and the static eliminator 15 is provided on the downstream side of the casing 21 in the paper feeding direction.
[0018]
For example, as shown in FIG. 3, the static eliminator 15 has a plurality of discharge tip electrodes 16-corresponding to the back surface in the paper width direction on one side edge, and a voltage of -1.5 KV is received from a high voltage power source (not shown). The neutralizing member 17 made of a stainless steel strip-like electrode plate (thickness 0.1 to 0.2 mm) to be applied and the discharge tip electrode 16-are supported from the back side, and the adjacent discharge tip electrode 16, 16 and a protective cover (protective member) that is detachably provided on the front surface of the static elimination member 17 in order to protect the static elimination member 17 and an insulating member 19 in which a plurality of projections 18-protruding beyond the thickness of the electrode are formed. 25).
[0019]
The protective cover 25 is formed such that a portion corresponding to the protrusion 18 of the insulating member 19 protrudes slightly forward and bends in a stepped manner. Alternatively, it can be attached to the front surface of the static elimination member 17 by a detachable attachment means such as a screw, and can be easily removed when the static elimination member 17 is cleaned. The state where the protective cover 25 is attached is shown in FIG.
[0020]
The insulating member 19 uses one side portion of the casing 21 of the transfer device 10, specifically, the side portion on the downstream side in the paper feeding direction of the casing 21 formed in a U-shaped cross section is the static eliminating device 15. A plurality of inverted triangular protrusions 18 in the figure are formed on the upper edge of the insulating member 19. A paper feed guide 26 is attached to the upstream side surface of the casing 21.
[0021]
On the other hand, the strip-shaped charge removing member 17 is fixed to the front surface of the insulating member 19, and the projections 18 of the insulating member 19 are arranged between the discharge tip electrodes 16 formed in the shape of the tip. The surface of the protrusion 18 is formed in a state protruding from the surface of the discharge tip electrode 16 by about 0.1 to 1 mm (protrusion amount t) (refer to the circle in the two-dot chain line in FIG. 3). The protrusion 18 is formed thicker than the discharge tip electrode 16 by the protrusion amount t.
[0022]
And, between each discharge tip electrode 16-, the projection 18 is arranged in a state with a predetermined interval as shown in FIG. 4, for example. That is, the angle of the tip of each discharge tip electrode 16 is set to 30 °, for example, and the interval between the discharge tip electrodes 16 and 16 is set to a pitch of 3 mm. A distance of 1 mm is set between the tip of the discharge tip electrode 16 and the base of the projection 18, and a portion of 1 to 2 mm from the tip of the discharge tip electrode 16 is set between the projections 18. Has been. In other words, the lower end of the protrusion 18 is set lower by about 1 to 2 mm than the upper end of the discharge tip electrode 16.
[0023]
As described above, the surface of the protrusion 18 is slightly protruded from the surface of the discharge tip electrode 16, and the protrusions 18 are arranged at predetermined intervals between the discharge tip electrodes 16. Thus, when the static elimination member 17 is cleaned, the discharge tip electrode 16 can be effectively protected by the projection 18, and the shape is not deformed or damaged even if accidentally contacted. It is also possible to avoid the occurrence of trouble that the service person cuts his / her finger.
[0024]
By the way, the transfer roller 23 is formed by winding a conductive elastic member such as EPDM or urethane around a metal core, and has an outer diameter of 14 to 20 mmφ and a hardness of 30 to 50 degrees (Asker C). Generally used. At the time of transfer, by applying a high voltage of about +1 KV to the transfer roller 23 to the charge removal member 17 to which a voltage of −1.5 KV is applied, a good charge removal effect can be obtained. Even if it is not applied, the effect of static elimination can be obtained.
[0025]
With such a charge removal device 15, effective charge removal is performed in a non-contact state with respect to the image-formed sheet, and the sheet can be stably conveyed to the downstream side, but is scattered around. Periodic cleaning is required to prevent the static elimination action from being reduced due to adhesion of toner or the like.
[0026]
At the time of cleaning, as shown in FIG. 5B, first, the protective cover 26 is removed, and a cleaning tool (not shown) made of a cloth material, a brush, or the like is moved in the direction of the arrow a toward the tip side. The static eliminating member 17 is cleaned. At that time, since the protrusion 18− protrudes slightly, the discharge tip electrode 16− is sufficiently protected, the tip portion is not deformed or damaged, and the finger is not cut. Easy, safe and efficient cleaning work can be completed.
[0027]
During such cleaning, even if the cleaning tool is mistakenly moved in the direction of the arrow b, the discharge tip electrode 16-is protected by the protrusion 18-, so that the cleaning tool is suddenly hooked on the tip. It is possible to avoid the occurrence of troubles such as injury to the finger.
[0028]
FIG. 6 shows a different embodiment, in which the protrusions 18—are alternate with respect to the discharge tip electrode 16—that is, between the two discharge tip electrodes 16, 18 between adjacent protrusions 18,18. A protrusion 18-is formed so as to sandwich 16. Thus, when forming the protrusion 18 at intervals, the protrusion amount t of the protrusion 18 with respect to the discharge tip electrode 16 (see the circle in the two-dot chain line in FIG. 3) is larger, for example, about 1 to 2 mm. It is preferable to set to.
[0029]
In the above-described embodiment, the static eliminator 17 is fixed to the insulating member 19, but the present invention is not limited to this. For example, the detachable attachment means such as a screw (protective cover) It is good also as a structure attached to the insulating member 19 so that attachment or detachment is possible.
[0030]
In the above-described embodiment, the insulating member 19 is formed integrally with the casing 21, but the present invention is not limited to this, and the insulating member 19 is formed separately from the casing 21, and the insulating member 19 is formed. It is good also as a structure which attaches 19 to the casing 21 detachably (with the static elimination member 17).
[0031]
【The invention's effect】
As is clear from the above description, the present invention has the following effects.
[0032]
According to the first aspect, the protrusion tip is protruded between the adjacent discharge tip electrodes more than the thickness of the electrode, so that the discharge tip electrode can be protected during the wiping operation, and the deformation or breakage is prevented. It is possible to prevent the occurrence of troubles such as injury by pinching a finger between the discharge tip electrodes.
[0033]
According to the second aspect, by disposing the discharge tip electrode between the projections, the discharge tip electrode can be protected by the projections, and deformation or breakage thereof can be prevented.
[0034]
According to the third aspect, since the protrusion of the insulating member protrudes toward the removable protective member side, the discharge tip electrode can be immediately cleaned by removing the protective member, and the protrusion The discharge tip electrode can be protected, and deformation, breakage, etc. can be avoided.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an image forming apparatus according to an embodiment of the present invention.
FIG. 2 is a configuration diagram of the main part.
FIG. 3 is an exploded perspective view of the main part.
FIG. 4 is a front view of the static eliminator.
FIG. 5 is a perspective view of the static eliminator.
FIG. 6 is a front view of a static eliminator according to a different embodiment of the present invention.
[Explanation of symbols]
6-Image carrier 10-Transfer device 15-Charging device 16-Discharge tip electrode 17-Charging member 18-Protrusion 19-Insulating member 25-Protective member

Claims (3)

A static eliminator provided on the downstream side of the transfer device for neutralizing the transfer material onto which the toner image on the image carrier has been transferred and separating the transfer material from the image carrier,
The static eliminator is
A charge removing member having a large number of discharge tip electrode formed continuously at an equal pitch over the width direction throughout the direction of the transfer material, while supporting the discharge tip electrode, on the surface side than the thickness of the discharge tip electrode A plurality of protrusions, which are protruding protrusions and are located in all or part of the space between adjacent discharge tip electrodes, and have insulating members formed at equal pitches over the entire area in the paper width direction. Characterized static eliminator. Between the projections adjoining neighbors, neutralization apparatus according to claim 1, characterized in that at least one discharge tip electrodes are positioned.   The insulating member is located closer to the transfer means than the charge eliminating member having the discharge tip electrode, and the protrusion of the insulating member is disposed on the protective member side detachably provided to cover the discharge tip electrode. 3. The static eliminator according to claim 1, wherein the static eliminator is protruded toward the surface.

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