JP3849776B2 - Transfer device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a transfer device of an image forming apparatus having a member that neutralizes charged charges of a transfer material after transfer.
[0002]
[Prior art]
Conventionally, in an image forming apparatus such as a copying machine, a toner image formed by a developing process is applied to a transfer paper by applying a transfer electric field. At this time, if there is an electric charge on the transfer paper, the toner flies and transfers. In order to prevent image deterioration due to adhesion to paper, the transfer paper is neutralized by a neutralization brush (Patent Document 1), and a static elimination needle is disposed at a position immediately after transfer by a transfer roller. The transfer paper is also neutralized (Patent Document 2).
[0003]
[Patent Document 1]
Japanese Examined Patent Publication No. 6-77170 [0004]
[Patent Document 2]
Japanese Patent No. 2759487 (Fig. 7)
[0005]
[Problems to be solved by the invention]
By the way, when the transfer paper after transfer is conveyed through the guide member in a state where charge removal is insufficient, contact with the rib of the guide member causes streak-like image disturbance due to static electricity. Further, for example, in a color image forming apparatus using an intermediate transfer medium, paper conveyed while being pressed against the secondary transfer roller and the intermediate transfer medium generates paper dust due to friction at the nip. In particular, the transfer paper that has passed through the fixing device once is greatly damaged by the pressure and heat of the roller, so more paper dust is generated, which accumulates on the static elimination member such as the static elimination brush and static elimination needle, Since the static elimination capability is remarkably lowered, it causes image disturbance. In addition, in order to improve the charge removal capability, a reverse bias is applied to the charge removal member at the time of transfer, so that the charge removal member plays the role of a dust collector such as paper dust floating in the machine. As a result, dirt is attached to the charge removal member and it is difficult to remove it, which causes image disturbance. However, the above Patent Document 1 and Patent Document 2 do not disclose this point at all.
[0006]
[Means for Solving the Problems]
SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and it is an object of the present invention to effectively neutralize a transfer paper and to maintain a static elimination capability in a durable manner.
The present invention provides a transfer device of an image forming apparatus in which a neutralizing cloth is integrally attached to an attracting plate that peels off a transfer material after transfer, wherein the neutralizing cloth is provided so that two or more layers can be peeled off. .
Further, the present invention is characterized in that the resistance value of the neutralizing cloth of each layer is changed.
Further, the present invention is characterized in that the voltage applied to the neutralization cloth of each layer is changed.
In addition, the present invention is characterized in that the distance between the outermost static elimination cloth and the transfer material can be adjusted.
Further, the present invention is characterized in that a film is interposed between the respective layers of the static eliminating cloth.
Further, the present invention is characterized in that an electrical leak preventing member is provided between the transfer roller, the attracting plate, and the static eliminating cloth, and only the outermost static eliminating cloth is exposed by the leak preventing member.
Further, the present invention is characterized in that a guide member for guiding the transfer material after transfer is provided, and the guide member and the attracting plate to which the neutralizing cloth is attached can be separated.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below.
FIG. 1 is a diagram illustrating an example of an image forming apparatus to which this embodiment is applied.
The photoreceptor 40 is uniformly charged by a charger (not shown), and an electrostatic latent image is formed by image exposure from the exposure device 41. A rotary developing unit 19 that develops toner on an electrostatic latent image has developing units of four colors Y, M, C, and K, and a developing roller 19a of each unit is positioned on the photosensitive member position by intermittent rotation of the rotary developing unit. In this position, toner development is performed facing the photoreceptor 40 at that position. The intermediate transfer medium 1 stretched by the driving roller 11, the driven roller 12, the support roller 15, the tension roller 13 and the like is separated from and abutted on the photosensitive member 40 at the position of the primary transfer roller 14, and is formed on the photosensitive member. The toner image is transferred to the intermediate transfer medium 1 (primary transfer), and four colors are superimposed on the intermediate transfer medium.
[0008]
A secondary transfer roller 29 that is brought into contact with the intermediate transfer medium 1 by a separation / contact mechanism 20 is provided at a position facing the driving roller 11 (also serving as a secondary transfer backup roller). The four color toner images are collectively transferred (secondary transfer). That is, the paper fed from the paper tray 50 by the paper feed roller 51 is conveyed to the position of the secondary transfer roller 29 through the paper conveyance path 52. While the color transfer is being performed on the intermediate transfer medium (during the primary transfer), the secondary transfer roller 29 is separated from the intermediate transfer medium. When applied, a four-color toner image is collectively transferred from the intermediate transfer medium to the paper (secondary transfer). The sheet after the secondary transfer passes through a paper guide 53 and is introduced into a fixing device 60 including a heating roller 60a and a pressure roller 60b, and is discharged to a discharge tray 61 on the upper surface of the apparatus.
[0009]
2 is a perspective view of a transfer paper guide used in the transfer apparatus of the present embodiment, FIG. 3 is a plan view of the back side of the transfer paper guide, FIG. 4 is a diagram illustrating a configuration example of a static elimination cloth, and FIG. It is a figure explaining the state which peeled off the static elimination cloth.
The transfer paper guide 1 according to this embodiment is a guide member 2 that guides the paper before transfer and guides it to the transfer position, a guide rib 3 attached thereto, a guide member 4 that guides the paper after transfer, and the guide member 4 attached thereto. A secondary transfer roller (not shown) is disposed at a transfer roller position 8 between the guide member 2 and the guide member 4 so as to perform secondary transfer with an intermediate transfer medium (not shown). Done. A neutralizing cloth 7 is attached integrally with a double-sided conductive adhesive tape (metal tape) and attached to the attracting plate 6 for preventing the paper after the transfer to the intermediate transfer medium side from being wound. The plate 6 is configured to be separable from the guide member 4. Therefore, only the attracting plate and the neutralizing cloth can be exchanged.
[0010]
A voltage having a predetermined polarity is applied to the attracting plate 6 and the neutralizing cloth 7 from a power source (not shown). In order to prevent an electrical leak from occurring between the transfer roller and the anti-leakage member 9, a leak preventing member 9 is provided. The attracting plate 6 is spring-biased by a clasp 10 and is pressed and fixed to the leak preventing member 9 side.
[0011]
The neutralizing cloth 7 is a non-woven fabric made of conductive ultrafine fibers such as a conductive polymer, and has an infinite number of tip portions as compared with conventional neutralizing brushes and neutralizing needles. The neutralization cloth of the example shown in FIG. 4 has a two-layer structure, and two neutralization cloths are sequentially laminated on the attracting plate 6 with double-sided conductive adhesive tape, and the neutralization cloth 7b is covered with the neutralization cloth 7a. ing. At this time, the second static elimination cloth is prevented from being exposed to the outside by the first static elimination cloth and the leak prevention member 9.
[0012]
Since the neutralizing cloth is a non-woven fabric made of ultrafine fibers, the floating toner adheres to the fiber tip as it is durable, and the neutralizing ability decreases. Therefore, the degree of soiling of the neutralizing cloth is evaluated based on the number of rotations of the intermediate transfer medium, the number of printed sheets, the printing duty, and the like. To use. In this way, long-term use is possible. Of course, it is not limited to the two-layer configuration, and may be three or more layers.
[0013]
FIG. 5 shows a state in which the first static eliminating cloth is peeled off. When the first sheet is peeled off, the second sheet is exposed and can be used as a new sheet. In addition, since the distance between the first sheet and the second sheet is different from the transferred sheet, strictly speaking, there is a difference in the discharge capacity. For example, the resistance value of the first sheet is changed to the resistance value of the second sheet. It is desirable to make it larger or to change the neutralization bias value applied to the first and second neutralization cloths. Alternatively, although not shown in the drawings, the height of the top surface neutralization cloth can be adjusted by providing a spacer or the like so that the heights of the first and second neutralization cloths can be made uniform. Also good.
[0014]
In addition, if the static eliminator cloths are laminated and pasted as they are, for example, the first adhesive material adheres to the second static eliminator cloth, and the static eliminator ability decreases. It is desirable not to touch the fibers of the neutralizing cloth directly.
[0015]
【The invention's effect】
As described above, according to the present invention, since the neutralizing cloth is a non-woven fabric made of ultrafine fibers, the tip shape of the neutralizing electrode becomes extremely thin, and countless neutralizing electrodes are formed. It is so excellent that it cannot be compared. In addition, since there is a dust collecting effect, there is a defect that paper dust is easily accumulated, but it can be used for a long time by placing it flat as a multilayer structure.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating an example of an image forming apparatus to which an exemplary embodiment is applied.
FIG. 2 is a perspective view of a transfer paper guide used in the transfer apparatus of the present embodiment.
FIG. 3 is a plan view of the back surface of the transfer paper guide.
FIG. 4 is a diagram illustrating a configuration example of a neutralizing cloth.
FIG. 5 is a diagram illustrating a state in which a first sheet of static elimination cloth has been peeled off.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Transfer paper guide, 2 ... Guide member, 3 ... Guide rib, 3 ... Guide member, 5 ... Guide rib, 6 ... Attracting plate, 7 ... Static elimination cloth, 8 ... Transfer roller position, 9 ... Leak prevention member, 10 ... Clasp , 19: Rotary developing unit, 19a: Developing roller, 29 ... Secondary transfer roller, 40 ... Photoconductor, 41 ... Exposure unit, 50 ... Paper tray, 51 ... Paper feeding roller, 52 ... Paper conveying path, 53 ... Paper Guide, 60... Fixing device, 61.

Claims (7)

In the transfer device of the image forming apparatus in which the neutralizing cloth is integrally attached to the attracting plate that peels off the transfer material after transfer,
The neutralizing cloth is provided so that two or more layers can be peeled off . The transfer device of claim 1, wherein the changing the resistance value of the neutralizing cloth of each layer. The transfer device of claim 1, wherein varying the voltage applied to each layer of neutralizing cloth. The transfer device according to claim 1, characterized in that the adjustable distance between the transfer material and the neutralizing cloth of the outermost layer. Claims 1 to 4 or according transfer device is characterized in that by interposing a film for neutralizing cloth between layers.   6. An electrical leak prevention member is provided between the transfer roller, the attracting plate, and the static elimination cloth, and only the outermost static elimination cloth is exposed by the leak prevention member. Transfer device.   2. The transfer apparatus according to claim 1, wherein a guide member for guiding the transfer material after transfer is provided, and the guide member and the attracting plate to which the neutralizing cloth is attached are separable.

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