JP2001042735A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the wear of an image carrier by preventing the warping of a sheet-like guide member while securing a sealing property as a cleaning device. SOLUTION: This image forming device is provided with a cleaning means 15a to remove toner on the image carrier, the sheet-like guide member 15f arranged on the upstream side of the cleaning means in the moving direction of the image carrier and to guide the toner removed by the cleaning means to the inside of a cleaner case 15c and a sealing member 15g to seal both side surfaces of the cleaner case, and the entire surface of the upstream side end of the sheet-like guide member is fixed (F) at the aperture edge of the cleaner case, and only the top part Q1 of the sheet-like guide member is overlapped (P) with the sealing member.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine and a printer using an electrophotographic method.
The present invention relates to a cleaning unit for removing toner remaining on an image carrier such as a photoconductor or an intermediate transfer body.

[0002]

2. Description of the Related Art In the above-mentioned image forming apparatus, an electrostatic latent image is formed on an image carrier such as a photoreceptor, and the electrostatic latent image is developed into a toner image, and then the toner image is transferred to a transfer material. After the transfer, the toner remaining on the image carrier is removed by a cleaning device. Conventionally, as such a cleaning device, for example, Japanese Patent Publication No. 4-4135
In Japanese Patent Application Publication No. JP-A-2005-115, as shown in FIG. 8, a cleaning blade 15a which comes into contact with an image carrier to scrape off toner
And a sheet-like guide member 15 that is in contact with the image carrier at a position upstream of the cleaning blade 15a.
f is provided to guide the toner scraped off by the cleaning blade 15a into the cleaner case. In order to prevent the toner in the cleaner case from scattering to the outside, a seal member 15g is provided at the opening end of the cleaner case 15c, and the seal member 15g and the end of the sheet-like guide member 15f are overlapped by a P portion. Like that. In this case, the sheet-like guide member 15
f is a sheet of PET or the like, the sealing member 15g is a soft foam material such as urethane foam, and the lower end of the sheet-like guide member 15f is fixed to the fixing portion F at the lower edge of the opening of the cleaner case 15c, leaving both side ends thereof. The both ends of the sheet-shaped guide member 15f are adhered to the sealing member 15g with an adhesive portion S, and as shown in FIG. I have.

[0003]

However, in the above-described conventional cleaning device, as shown in FIG. 8 (C), the leading end portion Q1 of the sheet-like guide member 15f abuts against the image carrier H and is relatively small. Fixed part F
Since the side is not in contact with the image carrier H, the sheet is warped by "straining" of the sheet, and the elastic force of the sealing member 15g acts, so that the edge of the side end Q2 of the sheet-shaped guide member 15f is It comes into contact with the carrier H, and as a result, there is a problem that the surface pressure with the image carrier increases and the wear of the image carrier becomes remarkable. Sheet guide member 15
f is in contact with the image carrier substantially in parallel with the function of contacting the image carrier to such an extent that the toner is not scraped off.
The sheet-like guide member 15f bulged out by the elastic force of the seal member 15g is inevitably brought into contact with the image carrier over a considerably wide range from the sheet-like guide member 15f distal end Q1 to the fixed portion side Q2. The contact pressure will be high. This abrasion is a particularly significant problem when the image carrier is a belt such as a light-sensitive material belt or an intermediate transfer belt.

The present invention solves the above-mentioned conventional problem, and prevents wear of an image carrier by preventing warpage of a sheet-shaped guide member while ensuring sealing performance as a cleaning device. It is an object of the present invention to provide an image forming apparatus capable of performing the above.

[0005]

For this purpose, an image forming apparatus according to the present invention includes a cleaning unit for removing toner on an image carrier and an upstream side of the cleaning unit with respect to a moving direction of the image carrier. A sheet-like guide member for guiding the toner removed by the cleaning unit into the cleaner case, and a seal member for sealing both side surfaces of the cleaner case, wherein an upstream end of the sheet-like guide member is provided.
The entire surface is fixed to the opening edge of the cleaner case, and only the leading end of the sheet-like guide member overlaps with the seal member.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram showing an example of an image forming apparatus to which the present invention is applied. This image forming apparatus is a color electrophotographic printer capable of forming a full-color image with four color toners. However, the present invention is not limited to this, and is applicable to all image forming apparatuses using electrophotography. Applicable.

The photoreceptor 1 has a thin cylindrical conductive substrate and a photosensitive layer formed on the surface thereof, and is driven to rotate in a direction indicated by an arrow by driving means (not shown). Around the photosensitive member 1, along a rotating direction thereof, a charging roller 2 as a charging unit, an exposure unit 3 for forming an electrostatic latent image on the photosensitive member 1, and a developing unit for developing the electrostatic latent image. Developing unit 4, an intermediate transfer device 5 for transferring the toner image formed on the photoconductor 1 onto the intermediate transfer belt 7,
A photoreceptor cleaning device 6 for removing the toner remaining on the top is disposed. In this embodiment, the charging roller 2 and the photoconductor cleaning device 6 are connected to the unit 8.
Is housed inside.

The developing unit 4 includes a developing unit 4 for yellow.
Y, a developing device 4C for cyan, a developing device 4M for magenta, and a developing device 4K for black.
4C, 4M, and 4K are provided so as to be swingable with respect to the photoconductor 1, so that only the developing roller 4a of one developing unit can selectively contact the photoconductor 1 for each rotation of the photoconductor 1. Have been. Then, the electrostatic latent image on the photoreceptor 1 is
C, 4M, and 4K are sequentially developed, and the developed toner images are sequentially transferred to an intermediate transfer belt (intermediate transfer body) 7 of the intermediate transfer device 5. Photoconductor cleaning device 6
Is a cleaning blade 6a (which is always in contact with the photoreceptor 1) for scraping off the toner remaining on and adhering to the outer peripheral surface of the photoreceptor 1 after the transfer of each toner image, and the cleaning blade 6a A collection unit 6b for storing the scraped-off toner.

The intermediate transfer device 5 includes a driving roller 9 for running the intermediate transfer belt 7, a backup roller 10 for primary transfer, a pre-primary transfer roller 11 for preventing wrinkling of the belt, a backup roller 12 for cleaning,
It is composed of a secondary transfer backup roller 13 and a tension roller 14 for applying tension to the belt. An endless intermediate transfer belt 7 is stretched around these rollers. The drive roller 9 is configured to be driven in synchronization with the photoconductor 1, whereby the intermediate transfer belt 7 is rotated at substantially the same peripheral speed as the photoconductor 1 in the direction indicated by the arrow in the figure. . The intermediate transfer belt 7 is urged toward the photoconductor 1 by a primary transfer backup roller 10, where a primary transfer portion T1 is formed.

Further, an intermediate transfer member cleaning device 15 is disposed so as to be able to contact and separate from the intermediate transfer belt 7 so as to face the cleaning backup roller 12. The cleaning device 15 includes a cleaning blade 15a that comes into contact with the intermediate transfer belt 7 and scrapes off toner remaining on and attached to the outer peripheral surface of the intermediate transfer belt 7;
Collection unit 1 containing toner scraped off by 5a
5b.

A secondary transfer roller 16 is opposed to the secondary transfer backup roller 13 with the intermediate transfer belt 7 interposed therebetween, and a secondary transfer portion T2 is formed here. An auxiliary cleaning device 17 is arranged downstream of the secondary transfer portion T2 so as to face the backup roller 13 for secondary transfer. The auxiliary cleaning device 17 includes a cleaning blade 17a that comes into contact with both side edges (outside the toner image area) of the intermediate transfer belt 7 and scrapes off the toner remaining on and attached to the outer peripheral surface of the intermediate transfer belt 7, and the cleaning blade 17a. And a recovery unit 17b for storing the toner scraped off by the cleaning unit.

The operation of the image forming apparatus having the above configuration will be described. When an image forming signal is input from a computer (not shown), the photosensitive member 1, each developing roller 4a of the developing unit 4, and the intermediate transfer belt 7 are driven to rotate. First, the outer peripheral surface of the photoconductor 1 is uniformly charged by the charging roller 2, and the outer peripheral surface of the uniformly charged photoconductor 1 is
The exposure unit 3 performs selective exposure L in accordance with the image information of the first color (for example, yellow) to form a yellow electrostatic latent image.

Only the developing roller 4a of the yellow developing unit 4Y comes into contact with the photoreceptor 1, whereby a yellow electrostatic latent image toner image is formed on the photoreceptor 1. A primary transfer voltage having a polarity opposite to the charge polarity of the toner is applied to the intermediate transfer belt 7, and the toner image formed on the photoconductor 1 is
The image is transferred onto the intermediate transfer belt 7 in the primary transfer section T1. At this time, the cleaning blade 15a of the secondary transfer roller 16 and the intermediate transfer body cleaning device 15 is
It is separated from the intermediate transfer belt 7. After the toner remaining on the photoreceptor 1 is removed by the photoreceptor cleaning device 6, the outer peripheral surface of the photoreceptor 1 is discharged by a discharger (not shown).

The above operation corresponds to the second, third, and fourth colors of the image forming signal, and the latent image formation and development by one rotation of the photosensitive member 1 and the intermediate transfer belt 7 are repeated. Four color toner images corresponding to the contents of the formation signal are superimposed and transferred on the intermediate transfer belt 7. Then, at the timing when this full-color image reaches the secondary transfer portion T2, the sheet S is supplied to the secondary transfer portion T2 from the direction of the arrow.
And a secondary transfer voltage is applied to transfer the full-color toner image on the intermediate transfer belt 7 onto the sheet S. At the same time, the cleaning blade 15a of the intermediate transfer body cleaning device 15 comes into contact with the intermediate transfer belt 7, and the toner remaining on the intermediate transfer belt 7 after the secondary transfer is removed and collected.

FIG. 2 shows the intermediate transfer member cleaning device 15 of FIG. 1, FIG. 2 (A) is a front view, and FIG. 2 (B) is a sectional view taken along line BB of FIG. 2 (A). is there. The intermediate transfer body cleaning device 15 is fixed to a cleaner case 15c having a toner collecting unit 15b therein, a toner conveying auger 15d disposed in the toner collecting unit 15b, and a holding case 15e to the cleaner case 15c. A cleaning blade 15a, a sheet-like guide member 15f having an upstream end fixed to a lower portion of the cleaner case 15c with respect to the moving direction of the intermediate transfer member, and a downstream end disposed close to the cleaning blade 15a; Case 15c
Is made of a sealing member 15g for sealing both side surfaces of the sealing member. As the sheet-like guide member 15f, urethane, P
It is a sheet material such as ET and the thickness is generally about 50 to 300 μm. On the other hand, the sealing member 15g is formed by forming a film having a relatively low coefficient of friction such as a fluororesin or high-density polyethylene on the surface of a flexible foam material such as urethane foam, or by forming a brush, and the thickness is determined by the amount of displacement It is set to about 1 to 5 mm in consideration of the weight.

FIG. 3 shows an embodiment of the present invention.
(A) is a partial plan view, and FIG. 3 (B) is BB in FIG. 3 (A).
It is sectional drawing seen in the arrow direction along the line. This embodiment is applied to the intermediate transfer body cleaning device 15 shown in FIG.

In this embodiment, the upstream end of the sheet-like guide member 15f is entirely covered with the cleaner case 15f.
c at the opening edge of the sheet-like guide member 15f.
The notch K is formed in the sealing member 15g so as not to contact with 5g.
Is provided so that only the leading end portion Q1 of the sheet-like guide member 15f overlaps the P portion. As a result, the fixed portion side Q2 of the sheet-shaped guide member 15f does not warp and contact the image carrier, and thus the wear of the image carrier can be prevented.

FIG. 4 shows another embodiment of the present invention. FIG. 4 (A) is a partial plan view, and FIG.
It is sectional drawing seen in the arrow direction along the B line. In the present embodiment, the upstream end of the sheet-like guide member 15f is
The entire surface is fixed to the opening edge of the cleaner case 15c by the fixing portion F, and the fixing portion side Q2 of the side end portion of the sheet-like guide member 15f is notched in the sheet-like guide member 15f so as not to contact the seal member 15g. K is provided so that only the leading end Q1 of the sheet-shaped guide member 15f overlaps the P portion.

FIG. 5 shows another embodiment of the present invention. FIG. 5 (A) is a partial plan view, and FIG.
It is sectional drawing seen in the arrow direction along the B line. In the present embodiment, the fixed portion side Q2 of the side end portion of the sheet-shaped guide member 15f is provided with a step D in the seal member 15g so as not to contact the seal member 15g.

FIG. 6 shows another embodiment of the present invention. FIG. 6 (A) is a partial plan view, and FIG.
It is sectional drawing seen in the arrow direction along the B line. In the present embodiment, an inclined surface G is formed on the sealing member 15g side from the fixed portion side Q2 of the side end portion of the sheet-shaped guide member 15f to the front end portion Q1, and the sheet-shaped guide member 15f is formed along the inclined surface G. I try to follow. In the present embodiment, it is not necessary to provide the overlap portion P as in the above embodiments.

FIG. 7 shows a preferred arrangement example in which the cleaning device according to the present invention is applied to belt cleaning. FIG. 7 (A) is an enlarged sectional view, and FIG. 7 (B) is a partial plan view. In this example, the cleaning means 15a is arranged so as to abut on the wrapping portion 12a of the belt 7 with the cleaning backup roller 12, and the wrapping portion 12a of the belt 7 is attached to the leading end Q of the sheet-like guide member 15f.
The sheet-like guide member 15f is arranged so that the sheet guide member 1 does not abut. As a result, the amount of deformation of the sheet-shaped guide member 15f is reduced, the force of rubbing the belt surface is reduced, and the belt has a smaller force than when the leading end portion Q1 of the sheet-shaped guide member 15f is in contact with the backup roller 12. Wear can be reduced.

Although the embodiment of the present invention has been described above, the present invention is not limited to this, and various modifications can be made. For example, in the above embodiment, the example of the cleaning device for the intermediate transfer belt is described. However, the present invention may be applied to the cleaning of the photosensitive material belt, or to the cleaning of the intermediate transfer drum and the photosensitive drum. May be. Further, in the above embodiment, the cleaning means of the cleaning device is a cleaning blade, but may be a cleaning brush.

[0023]

As is apparent from the above description (1), according to the present invention, the image bearing member is prevented from being worn by preventing the sheet-shaped guide member from warping while ensuring the sealing performance as a cleaning device. can do.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram illustrating an example of an image forming apparatus to which the present invention is applied.

2A and 2B show the intermediate transfer body cleaning device of FIG. 1; FIG. 2A is a front view, and FIG. 2B is BB of FIG. 2A;
It is sectional drawing which follows a line.

3A and 3B show one embodiment of the present invention, and FIG. 3A is a partial plan view, and FIG. 3B is a cross-sectional view taken along line BB of FIG. It is.

4A and 4B show another embodiment of the present invention, in which FIG. 4A is a partial plan view, and FIG. 4B is a cross section taken along line BB of FIG. FIG.

FIG. 5 shows another embodiment of the present invention, and FIG.
5A is a partial plan view, and FIG. 5B is a BB view of FIG.
It is sectional drawing seen in the arrow direction along the line.

6A and 6B show another embodiment of the present invention, in which FIG. 6A is a partial plan view, and FIG. 6B is a cross-sectional view taken along line BB of FIG. FIG.

FIG. 7 shows a preferred arrangement example when the cleaning device according to the present invention is applied to belt cleaning,
7A is an enlarged sectional view, and FIG. 7B is a partial plan view.

FIG. 8 illustrates a conventional cleaning device, and FIG.
8 is a partial plan view, FIG. 8B is a diagram viewed from a direction B in FIG. 8A, and FIG. 8C is a diagram for explaining a problem of the present invention.

[Explanation of symbols]

 7 ... Image carrier 12 ... Backup roller 12a ... Wrapping part 15a ... Cleaning means 15c ... Cleaner case 15f ... Sheet guide member 15g ... Seal member D ... Step part F ... Fixed part G ... Slope K ... Notch part P ... Overlapping part Q1 ... tip

Claims (6)

[Claims] A cleaning unit that removes toner on the image carrier; and a sheet that is disposed upstream of the cleaning unit with respect to a moving direction of the image carrier and guides the toner removed by the cleaning unit into a cleaner case. A guide member, and a seal member for sealing both side surfaces of the cleaner case, an upstream end of the sheet-like guide member,
An image forming apparatus, wherein the entire surface is fixed to an opening edge of a cleaner case, and only a leading end of a sheet-shaped guide member overlaps with a seal member. 2. The image forming apparatus according to claim 1, wherein a notch is provided in the seal member so that only the leading end of the sheet-shaped guide member overlaps the seal member. 3. The sheet-like guide member is provided with a notch so that only the leading end of the sheet-like guide member overlaps with the seal member.
The image forming apparatus as described in the above. 4. The image forming apparatus according to claim 1, wherein a step portion is provided on the seal member so that only the leading end of the sheet-shaped guide member overlaps with the seal member. 5. A cleaning device for removing toner on an image carrier, and a sheet disposed upstream of the cleaning device with respect to a moving direction of the image carrier, for guiding the toner removed by the cleaning device into a cleaner case. A guide member, and a seal member for sealing both side surfaces of the cleaner case, an upstream end of the sheet-like guide member,
The entire surface is fixed to the opening edge of the cleaner case, and the sealing member is formed with an inclined surface from the fixed portion side of the sheet-shaped guide member to the tip portion, and the sheet-shaped guide member is made to follow the inclined surface. An image forming apparatus comprising: 6. The image bearing member is a belt, and further includes a backup roller with which the cleaning unit comes into contact via the belt, and a leading end of the sheet-like guide member is provided at a portion where the belt is wound around the backup roller. The image forming apparatus according to claim 1, wherein a sheet-shaped guide member is arranged so that the portions do not abut.