JPH11338265A - Transfer electrifier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely clean both of an electrifying wire and a discharge needle nearly at the same time by cleaning either the electrifying wire or the discharge needle interlocked with movement for cleaning the other. SOLUTION: The lower part of the discharge needle 62 is held and fixed by a fixing member 64. An L-shaped arm 68 is formed on an inner side part of the member 64 in a taking-in and taking-out direction. A cleaning pad part 70 for cleaning the electrifying wire is fixed at the edge of the arm 68. A cleaning pad 72 made of sponge-like material for cleaning the electrifying wire 54 is attached to the pad part 70. In the case of cleaning the needle 62, the member 64 where the needle 62 is fixed is pulled out, and the needle 62 is separated from a photoreceptor drum. When the member 64 is pulled out in order to clean the needle 62, the pad part 70 is also moved together with the arm 68 and the wire 54 is cleaned by the movement of the pad part 70.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer charger for charging a recording medium for transfer in an image forming apparatus for forming an image by transferring a developed image to the recording medium and thereafter removing the charge of the recording medium. About.

[0002]

2. Description of the Related Art As an output device of a computer or a workstation, an electrophotographic image forming apparatus for forming an image on a recording medium using a developer (toner) or the like is known. This electrophotographic image forming apparatus includes, for example,
An original mounting table on which the original is mounted is provided. The original mounted on the original mounting table is irradiated with light from below the original mounting table, and a drum-shaped image carrier (photosensitive drum) is moved to a predetermined position. While rotating at the process speed, the photosensitive drum is uniformly charged by a charger, and a light carrying information of an image recorded on a document is irradiated on the photosensitive drum to form an electrostatic latent image on the photosensitive drum. This is an apparatus that develops an electrostatic latent image using a developer to form a developed image, and transfers the developed image to a recording medium such as recording paper to obtain a print image (copy image).

[0003] Such an image forming apparatus is usually provided with a transfer charger for transferring a developed image to recording paper or the like. The transfer charger gives the recording paper a charge opposite to the toner charge from the back side of the recording paper, for example, and charges the recording paper.
This is to transfer the developed image to recording paper. The transfer charger is generally provided with a charging line for charging the recording paper. This charging line extends in the direction of the rotation axis of the photosensitive drum.

Further, the recording paper charged by the transfer charger is easily attracted to the photosensitive drum. Therefore, in order to easily separate the recording paper from the photosensitive drum, the transfer charger may be provided with a static elimination needle for removing charges from the charged recording paper and discharging the recording paper. . This static elimination needle also extends in the rotation axis direction of the photosensitive drum.

However, when the image forming apparatus is used for a long period of time, toner or paper dust adheres to the charged wire or the static elimination needle, and these become dirty. If the charged wire becomes dirty, the discharge from the charged wire may become uneven, resulting in poor transfer. Further, if the static elimination needle is stained, the static elimination capability of the static elimination needle is reduced, and the recording paper may not be separated from the photosensitive drum in some cases. Therefore, the charging wire and the static elimination needle are cleaned to prevent the occurrence of troubles such as transfer failure and separation failure. In cleaning the charged wire, the charged wire is cleaned with, for example, a dedicated cleaning pad. When cleaning the static elimination needle, the static elimination needle is cleaned with, for example, a brush.

[0006]

Conventionally, as described above, a charged pad is cleaned with a cleaning pad, and a static elimination needle is cleaned with a brush. For this reason, the cleaning of the charging wire and the cleaning of the static elimination needle must be performed separately. For example, although the charging wire is cleaned, the cleaning of the static elimination needle may be forgotten.

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a transfer charger capable of surely cleaning both a charging wire and a static elimination needle almost simultaneously.

[0008]

In order to achieve the above object, a transfer charger of the present invention forms an electrostatic latent image on an image carrier and supplies a developer to the electrostatic latent image to form a developed image. In an image forming apparatus for forming an image by transferring the developed image to a recording medium in a predetermined transfer area to form an image, a portion of the recording medium located in the transfer area is charged and the developed image is transferred to the portion. A transfer charger for discharging a portion of the recording medium on which the developed image has been transferred; (1) a charging line for charging a portion of the recording medium located in the transfer area; And a static elimination needle for static elimination of a portion where the developed image has been transferred, (3) the charging line and the static elimination needle
It is characterized in that the other is cleaned in conjunction with the movement for cleaning one of the charged wire and the static elimination needle.

The static elimination needle may be (4) integrally formed with or connected to a charging wire cleaner for cleaning the charging wire.

The charging wire may be (5) integrally formed with or connected to a cleaning member for a static elimination needle for cleaning the static elimination needle.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a transfer charger of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing the appearance of a copying machine in which the transfer charger of the present invention is incorporated.

A copy press (which is an example of an image forming apparatus according to the present invention) 10 has an original cover 12 that can be opened and closed on the top surface thereof. On the front side of the top surface, an operation panel display 14 for inputting the number of copies and the like is arranged.
The copying machine 10 is provided with a universal cassette 16 for accommodating a plurality of cut sheets so that the universal cassette 16 can be taken in and out from the front side of the copying machine 10. The right side wall of the copying machine 10 is provided with a rectangular manual tray 18 (see FIG. 2) capable of feeding small-size recording paper such as postcards.
As shown in FIG. 2, the manual feed tray 18 is
It rotates in the direction of arrow C around the center 8a, and opens to the position where the recording medium can be placed (the position indicated by the two-dot chain line). The left side wall of the copying machine 10 is provided with a paper discharge tray 20 on which recording paper on which an image is formed is stacked.

At the front of the copier 10, a rectangular front door 22 is provided.
However, it is fixed so that it may open to the near side with the lower side portion 22a as the center of rotation. By opening the front door 22, the inside of the copier 10 can be observed.

Referring to FIG. 2, a procedure for forming an image by the copying machine 10 of FIG. 1 will be described.

FIG. 2 is a schematic diagram showing an outline of the internal structure of the copying machine 10. As shown in FIG. 2, the same components as those of FIG. 1 are denoted by the same reference numerals.

An original platen glass 26 on which an original 24 is placed is arranged below the original cover 12. The original 24 is placed on the original platen glass 26 so that the image surface faces downward, and the original 24 is pressed and fixed by the original cover 12. The image recorded on the document 24 is read by a well-known optical system 28 having a light source lamp (not shown) or the like, and light (indicated by a broken line A) carrying information of the image recorded on the document is obtained. . This light is applied to the photosensitive drum 32 uniformly charged by the charging unit 30 to form an electrostatic latent image. This electrostatic latent image is developed with the developer (toner) supplied from the developing unit 34 to form a developed image. On the other hand, a recording medium such as recording paper sent from the universal cassette 16 is fed in the direction of arrow B, and the developed image is transferred to the recording medium by the transfer charger 36.

The recording medium on which the developed image has been transferred is conveyed to a fixing device 40 by a conveying device 38. The fixing device 40 is provided with a heat roller 42 and a press roller 44. The recording medium is conveyed while being sandwiched between these two rollers 42, 44, and the developed image is fixed on the recording medium. The recording medium on which the developed image has been fixed in this manner is discharged and stacked on the discharge tray 20. The toner remaining on the photosensitive drum 32 after the transfer is scraped off by the cleaning device 46. In addition, the recording medium can be fed from the manual feed tray 18, and the procedure for forming an image on the recording medium fed from the manual feed tray 18 is the same as described above.

The transfer charger 36 will be described with reference to FIGS.

FIG. 3 is an enlarged side view showing the transfer charger, and FIG. 4 is a perspective view showing a part of the transfer charger. In these drawings, the same components as those in FIG. 2 are denoted by the same reference numerals.

The overall shape of the transfer charger 36 is a shape extending in the direction of the rotation axis of the photosensitive drum 32 (the direction of arrow C).
The transfer charger 36 is disposed in a transfer area 52 where a developed image is transferred onto the recording paper P conveyed in the direction of arrow B. The transfer charger 36 includes a charging unit 50 that charges a portion of the recording medium P located in the transfer area 52, and a discharging unit 60 that discharges a portion of the recording medium P on which a developed image has been transferred.
They are roughly divided into

The charging section 50 has a shield plate 53 extending in the direction of arrow C, and a charging line 54 surrounded by the shield plate 53 and extending in the direction of arrow C. The shield plate 53 has a bottom wall 53a and a side wall 53a, and has an open upper surface. The charging wire 54 is located substantially at the center of the space surrounded by the shield plate 53. Both ends of the charging wire 54 are fixed to the front block 36a and the back block 36b to which electrodes and the like are attached by using a tension spring or the like. is there. The discharge from the charging line 54 causes the recording medium P
Is charged.

The static elimination section 60 is formed adjacent to the charging section 50 and includes a static elimination needle 62 extending in the direction of arrow C. The static elimination needle 62 is a plate having a thickness of about 0.1 mm, and a saw-tooth-shaped projection 62a is continuously formed on an upper portion thereof. The lower portion of the static elimination needle 62 is sandwiched and fixed by a fixing member 64. The fixing member 64 is configured to be freely put in and taken out in the arrow C direction, and is guided in the arrow C direction by a guide rail 66 extending in the arrow C direction.

An "L" -shaped arm 68 is formed at the back of the fixing member 64 in the direction of insertion and removal (in the direction of arrow C). A cleaning pad portion 70 (an example of a charging wire cleaner member according to the present invention) for cleaning the charging wire 54 is fixed to the tip of the arm 68. Further, a cleaning pad 72 made of a sponge-like material for cleaning the charged wire 54 is attached to the cleaning pad section 70. For this reason, the static elimination needle 62 and the cleaning pad part 70 are integrally formed.
As a result, when the fixing member 64 is moved in and out in the direction of arrow C, the cleaning pad unit 70 also moves in the direction of arrow C. The cleaning pad 70 has a ring shape, and an inner peripheral surface thereof is in contact with the charging wire 54. Therefore, the charging line 54 is cleaned by moving the cleaning pad unit 70 in the direction of arrow C.

The charging wire 54 and the discharging needle 62 are contaminated by paper dust of the recording medium P passing above them, toner of the photosensitive drum 32, and the like. For this reason, the charging wire 54 and the discharging needle 62 are cleaned. When cleaning the static elimination needle 62, the fixing member 64 fixing the static elimination needle 62 is pulled out in the direction of arrow C as shown by the two-dot chain line in FIG. 4 to separate the static elimination needle 62 from the photosensitive drum 32. As a result, a space for cleaning is formed above the static elimination needle 62, and the static elimination needle 62 is cleaned in this space with a brush (not shown) or the like.

A fixing member 64 for cleaning the static elimination needle 62
Is pulled out in the direction of arrow C, the cleaning pad unit 70 also moves in the direction of arrow C together with the arm 68, and this movement cleans the charged wire 54. Therefore, the charging line 54 is cleaned in conjunction with the movement for cleaning the charge removing needle 62. Therefore, both the charging wire 54 and the static elimination needle 62 can be surely cleaned almost at the same time, and there is no need to forget these cleanings. Even if you want to clean only the charged wire 54,
It is only necessary to pull out the static elimination needle 62, and it is not necessary to take out the charger unit outside the machine, and cleaning can be performed easily.

In the above-described example, the cleaning pad 70 for cleaning the charging wire 54 is formed integrally with the static elimination needle 62. Conversely, a cleaning member for the static elimination needle 62 for cleaning the static elimination needle 62 is connected to the charging wire 54. It may be configured integrally so that the static elimination needle 62 is also cleaned almost simultaneously with the cleaning of the charged wire 54. Further, the cleaning pad portion 70 and the cleaning member for the static elimination needle may be integrally configured so that when the charging wire 54 is cleaned, the static elimination needle 64 is also cleaned at the same time. The cleaning pad 70 is made of an elastic material such as resin. When the static elimination needle is set, the brim portion 72 of the cleaning pad 70 is opened by the cutouts 53c and 53d provided on the side wall of the shield plate. 70 is configured to open in a direction away from the charging wire 54 by its own elastic force. For this reason, the position of the charging line 54 returns to the normal position during copying. The cleaning pad section 70 shown by the two-dot chain line in FIG. 3 shows the open state.

[0028]

As described above, according to the transfer charger of the present invention, the other is cleaned in conjunction with the movement for cleaning one of the charging wire and the discharging needle. When either one of them is cleaned, both the charged wire and the static elimination needle are surely cleaned, and both the charged wire and the static elimination needle can be surely cleaned almost at the same time without forgetting to clean them.

Here, when the static elimination needle is formed integrally with the charging wire cleaner member for cleaning the charged wire, when the static elimination needle is moved to clean the static elimination needle, the charging wire is moved with this movement. Since the cleaner member moves to clean the charged wire, both the charged wire and the static elimination needle can be reliably cleaned.

When the charged wire is formed integrally with the charge removing needle cleaner member for cleaning the charge removing needle, when the charged wire is moved to clean the charged wire, the movement of the charge removing needle is caused by this movement. Since the cleaner member moves to clean the static elimination needle, both the charged wire and the static elimination needle can be reliably cleaned.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the appearance of a copying machine in which a transfer charger of the present invention is incorporated.

FIG. 2 is a schematic diagram showing an outline of an internal structure of the copying machine shown in FIG. 1;

FIG. 3 is an enlarged side view showing a transfer charger.

FIG. 4 is a perspective view showing a part of the transfer charger of FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Copier 36 Transfer charger 54 Charging wire 62 Static elimination needle 70 Cleaning pad part 72 Cleaning pad

Claims (3)

[Claims] An electrostatic latent image is formed on an image carrier, a developer is supplied to the electrostatic latent image to form a developed image, and the developed image is transferred to a recording medium in a predetermined transfer area. In an image forming apparatus for forming an image, a transfer charger for charging a portion of the recording medium located in the transfer area to transfer a developed image to the portion, and for removing a portion of the recording medium on which the developed image has been transferred, a transfer charger. A charge line for charging a portion of the recording medium located in the transfer area; and a charge elimination needle for discharging a portion of the recording medium on which a developed image is transferred, wherein the charge line and the charge elimination are provided. The transfer charger, wherein the needle is cleaned in conjunction with movement for cleaning one of the charging wire and the discharging needle. 2. The transfer charger according to claim 1, wherein the static elimination needle is integrally formed with or connected to a charging wire cleaner for cleaning the charging wire. 3. The transfer charger according to claim 1, wherein the charging wire is formed integrally with or connected to a charge elimination needle cleaner member for cleaning the charge elimination needle.