JP2022182475A - Image forming apparatus - Google Patents

Abstract

To collect waste toner with a low-cost and simple configuration.SOLUTION: An image forming apparatus comprises: an intermediate transfer belt 15B that is wound over a drive roller 15D and a driven roller 15N and revolves while holding toner; a blade 31 that is in contact with a planar area 15P of the intermediate transfer belt 15B where the drive roller 15D and driven roller 15N and the intermediate transfer belt 15B are not in contact with each other; and a waste toner container 33 that stores waste toner scraped off by the blade 31 from the intermediate transfer belt 15B. A linear contact part of the blade 31 and the intermediate transfer belt 15B is inclined with respect to a revolving direction A of the intermediate transfer belt 15B.SELECTED DRAWING: Figure 5

Description

The present invention relates to an image forming apparatus having a function of removing toner adhering to an intermediate transfer belt.

An image forming apparatus that forms a color image by electrophotography forms a color toner image by superimposing and transferring toner images of each color onto an intermediate transfer body. Toner may remain. Therefore, conventionally, techniques for removing toner from the intermediate transfer body have been studied. For example, in Patent Document 1, toner collected in a belt cleaning unit is guided to the side of the apparatus main body via an intermediate box and a duct by the rotation of a conveying screw, discharged into a relay duct, dropped by its own weight, and fed. It has been proposed to secure a jam processing space by collecting waste toner in a waste toner storage box provided in a table.

JP-A-5-61385

However, the configuration proposed in Patent Literature 1 requires a conveying screw and a mechanism for driving it, resulting in an increase in cost. Moreover, there is a possibility that the waste toner melts and adheres due to the temperature rise in the image forming apparatus, and the conveying screw does not move.

SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus capable of recovering waste toner with a low cost and a simple structure.

In order to solve the above problems, an image forming apparatus according to the present invention provides an intermediate transfer belt that is wound around a plurality of rollers and rotates while holding toner; a blade contacting a planar region of an intermediate transfer belt; and a waste toner container for storing waste toner scraped off from the intermediate transfer belt by the blade, wherein the blade and the intermediate transfer belt form a linear shape. is inclined with respect to the rotation direction of the intermediate transfer belt.

The contact portion may be formed in a straight line in the longitudinal direction of the blade, and the waste toner container may be provided below an end located on the back side in the circumferential direction of both ends of the contact portion.

The contact portion may be V-shaped in which both ends of the blade in the longitudinal direction are located deeper than the central portion in the circumferential direction, and the waste toner container may be provided below both ends of the contact portion.

According to the present invention, waste toner can be collected at low cost and with a simple configuration.

1 is a perspective view showing the appearance of an image forming apparatus according to an embodiment of the invention; FIG. 1 is a front view schematically showing an internal configuration of an image forming apparatus according to an embodiment of the invention; FIG. 1 is a perspective view of an intermediate transfer unit according to one embodiment of the invention; FIG. 3 is a cross-sectional view of an intermediate transfer unit according to one embodiment of the invention; FIG. 3 is a perspective view showing how a blade and a waste toner container are arranged in an intermediate transfer unit according to one embodiment of the present invention; FIG. FIG. 2 is a side view showing how a blade and a waste toner container are arranged in an intermediate transfer unit according to one embodiment of the present invention; 2 is a plan view schematically showing a blade and an intermediate transfer belt according to one embodiment of the invention; FIG. FIG. 11 is a perspective view showing how a blade and a waste toner container are arranged in an intermediate transfer unit according to a modification of one embodiment of the present invention;

An image forming apparatus 100 according to an embodiment of the present invention will be described below with reference to the drawings.

First, the overall configuration of image forming apparatus 100 will be described. FIG. 1 is a perspective view showing the appearance of the image forming apparatus 100. As shown in FIG. FIG. 2 is a front view schematically showing the internal configuration of the image forming apparatus 100. As shown in FIG. 2 is the front side (front side) of the image forming apparatus 100, and the left and right directions are based on the direction when the image forming apparatus 100 is viewed from the front. In each figure, U, Lo, L, R, Fr, and Rr indicate up, down, left, right, front, and rear, respectively.

The image forming apparatus 100 includes a printer 1 , a scanner 110 and a document conveying device 120 . A scanner 110 is provided above the printer 1 , and a document conveying device 120 is provided above the scanner 110 . The document conveying device 120 conveys the document along a conveying path passing through the reading position of the scanner 110 . The scanner 110 is a flatbed image scanner that reads a document and generates image data. The printer 1 forms an image on a sheet S based on image data.

Printer 1 and scanner 110 are integrated by housing 3 . In the lower part inside the housing 3, a paper feed cassette 4 in which the sheets S are accommodated and a paper feed roller 5 for feeding the sheets S backward from the paper feed cassette 4 are provided. The paper feed cassette 4 can be pulled forward. An image forming device 6 that forms a toner image by electrophotography is provided above the paper feed cassette 4, and a fixing device 7 that fixes the toner image onto the sheet S is provided above and behind the image forming device 6. It is A paper discharge roller 8 for discharging the sheet S having the toner image fixed thereon and a paper discharge tray 9 for stacking the discharged sheet S are provided above and in front of the fixing device 7 .

Inside the housing 3 , a transport path 10 is provided from the paper supply roller 5 to the paper discharge roller 8 via the image forming device 6 and the fixing device 7 . The transport path 10 is mainly formed of plate-like members facing each other with a gap for allowing the sheet S to pass therethrough. there is A registration roller 18 is provided upstream of the imaging device 6 in the transport direction Y. As shown in FIG. Behind the fixing device 7, a transport path 10R is provided that branches from the transport path 10 downstream of the fixing device 7 in the transport direction Y and joins the transport path 10 upstream of the registration roller 18 in the transport direction Y. there is

The front side of the housing 3 is provided with an opening 3A and a door 3D that closes the opening 3A. The lower end of door 3D is coupled to housing 3 using hinge 3H. The door 3D is opened during maintenance of the imaging device 6 and the like. The door 3D also serves as a manual feed tray for manually feeding the sheet S. A paper feed roller 21 is provided above the hinge 3H, and a transport path 10T that joins the transport path 10 from the paper feed roller 21 through between the paper feed cassette 4 and the image forming device 6 is provided. there is

The image forming device 6 includes a photoreceptor drum 11 whose electric potential changes when irradiated with light, a charging device 12 that charges the photoreceptor drum 11, an exposure device 13 that emits a laser beam according to image data, and toner on the photoreceptor drum 11. , an intermediate transfer unit 15 for transferring a toner image from the photoreceptor drum 11 to the sheet S, and a cleaning device 16 for removing toner remaining on the photoreceptor drum 11 . The intermediate transfer unit 15 has an endless intermediate transfer belt 15B wound around a plurality of rollers, and faces the inner peripheral surface of the intermediate transfer belt 15B at a position corresponding to the photoreceptor drum 11. The primary transfer unit 15 generates a primary transfer bias. A roller 151 and a secondary transfer roller 152 facing the outer peripheral surface of the intermediate transfer belt 15B and generating a secondary transfer bias are provided. A toner container 20 that supplies toner to the developing device 14 is connected to the developing device 14 .

The control unit 2 includes an arithmetic unit and a storage unit. The calculation unit is, for example, a CPU (Central Processing Unit). The storage unit includes storage media such as ROM (Read Only Memory), RAM (Random Access Memory), and EEPROM (Electrically Erasable Programmable Read Only Memory). The calculation unit performs various processes by reading and executing the control program stored in the storage unit. Note that the control unit 2 may be implemented by an integrated circuit that does not use software.

An operation panel 19 is provided on the front side of the scanner 110 . The operation panel 19 includes a display panel, a touch panel overlaid on the display surface of the display panel, and a keypad adjacent to the display panel. The control unit 2 displays screens representing operation menus, statuses, etc. of the printer 1 and the scanner 110 on the display panel, and controls each unit of the printer 1 and the scanner 110 according to operations detected by the touch panel and the keypad.

A basic image forming operation of the image forming apparatus 100 is as follows. When a print job for single-sided printing is input to the printer 1 from an external computer or the like, the paper feed roller 5 feeds the sheet S from the paper feed cassette 4 to the transport path 10, and the registration roller 18 whose rotation is stopped moves the sheet S. The skew is corrected, and the registration rollers 18 feed the sheet S to the image forming device 6 at a predetermined timing. In the image forming device 6 , the charging device 12 charges the photosensitive drum 11 to a predetermined potential, the exposure device 13 writes a latent image on the photosensitive drum 11 , and the developing device 14 applies toner supplied from the toner container 20 . A toner image is formed by developing the latent image using the primary transfer roller 151 to transfer the toner image to the intermediate transfer belt 15B, and the secondary transfer roller 152 transfers the toner image to the sheet S. FIG. Subsequently, the fixing device 7 fuses the toner image while nipping and conveying the sheet S to fix the toner image on the sheet S, and the sheet discharge roller 8 discharges the sheet S to the sheet discharge tray 9 . The cleaning device 16 removes toner remaining on the photoreceptor drum 11 . In the case of double-sided printing, the toner image is transferred to the second surface by feeding the sheet S having the toner image fixed on the first surface thereof to the transport path 10 via the transport path 10R.

Next, a configuration for removing toner from the intermediate transfer belt 15B will be described. FIG. 3 is a perspective view of the intermediate transfer unit 15. FIG. FIG. 4 is a cross-sectional view of the intermediate transfer unit 15. As shown in FIG. FIG. 5 is a perspective view showing how the blade 31 and the waste toner container 33 are arranged in the intermediate transfer unit 15. As shown in FIG. FIG. 6 is a side view showing how the blade 31 and the waste toner container 33 are arranged in the intermediate transfer unit 15. As shown in FIG. FIG. 7 is a plan view schematically showing the blade 31 and the intermediate transfer belt 15B.

The image forming apparatus 100 includes an intermediate transfer belt 15B that is wound around a drive roller 15D and a driven roller 15N (an example of a plurality of rollers) and that holds toner and rotates, the drive roller 15D and the driven roller 15N, and the intermediate transfer belt 15B. and a waste toner container 33 for storing waste toner scraped from the intermediate transfer belt 15B by the blade 31. A linear contact portion with the intermediate transfer belt 15B is inclined with respect to the rotation direction A of the intermediate transfer belt 15B.

[Intermediate transfer belt]
The intermediate transfer unit 15 (see FIGS. 2 to 4) includes a drive roller 15D, a driven roller 15N, an intermediate transfer belt 15B and a primary transfer roller 151. As shown in FIG. A driving roller 15D is provided on the rear side and a driven roller 15N is provided on the front side, and an endless intermediate transfer belt 15B is wound around the driving roller 15D and the driven roller 15N. The drive roller 15D is driven counterclockwise in FIG. 4 to rotate the intermediate transfer belt 15B in the A direction. The four photoreceptor drums 11 are provided below the intermediate transfer belt 15B, and four primary transfer rollers 151 are provided at positions facing the photoreceptor drums 11 inside the intermediate transfer belt 15B. The secondary transfer roller 152 is in contact with the intermediate transfer belt 15B while holding the intermediate transfer belt 15B between itself and the drive roller 15D.

[blade]
The blade 31 (see FIGS. 5 to 7) is an elongated plate-like member. The intermediate transfer belt 15B has two upper and lower planar regions that do not contact the driving roller 15D and the driven roller 15N. Of these, the blade 31 is in contact with the outer surface of the planar region 15P (see FIG. 5) on the upper side, that is, the side on which the photosensitive drum 11 is not provided. A contact portion between the tip portion 31E of the blade 31 and the intermediate transfer belt 15B is linear. A base portion 31B of the blade 31 is a portion including an end portion opposite to the tip portion 31E. A holder 32 is coupled to the base portion 31B of the blade 31 . The blade 31 is provided via a holder 32 on a frame (not shown) that supports the intermediate transfer unit 15 . The blade 31 may be fixed or pressed against the intermediate transfer belt 15B by a spring.

A tip portion 31E of the blade 31 is formed in a straight line in the longitudinal direction of the blade 31. As shown in FIG. Therefore, the linear contact portion between the blade 31 and the intermediate transfer belt 15B is also straight. The tip 31E of the blade 31 crosses the rotation direction A of the intermediate transfer belt 15B at an angle of less than 90°. That is, the linear contact portion between the blade 31 and the intermediate transfer belt 15B is inclined with respect to the rotation direction A. As shown in FIG. The blade 31 is arranged in a posture in which the tip portion 31E is in contact with the intermediate transfer belt 15B and the base portion 31B is separated from the intermediate transfer belt 15B.

[Waste Toner Container]
The waste toner container 33 (see FIGS. 5 and 6) is a bottle having a receiving opening 33A at the top. The waste toner container 33 is provided below the right end of the blade 31 . Further, the waste toner container 33 is provided to the right of the paper feed cassette 4 so as not to interfere with the paper feed cassette 4 when the paper feed cassette 4 is pulled forward.

Next, the operation of the above configuration will be described. In the image forming device 6 (see FIG. 2), the charging device 12 charges the photoreceptor drum 11 to a predetermined potential, the exposure device 13 writes a latent image on the photoreceptor drum 11, and the developing device 14 charges the toner from the toner container 20 . A toner image is formed by developing the latent image using the supplied toner, the primary transfer roller 151 transfers the toner image to the intermediate transfer belt 15B, and the secondary transfer roller 152 transfers the toner image to the sheet S. . After that, the waste toner remaining on the intermediate transfer belt 15B is conveyed by the intermediate transfer belt 15B (direction A in FIGS. 5 to 7) and collides with the tip 31E of the blade 31. FIG.

At this time, the waste toner is acted upon by the driving force F of the intermediate transfer belt 15B and the vertical resistance N exerted by the blade 31, so that the waste toner moves in the direction of the resultant force R of the driving force F and the vertical resistance N ( See Figure 7). The direction of the resultant force R substantially coincides with the longitudinal direction (B direction) of the tip portion 31E of the blade 31 . Waste toner may run on the blade 31, but the blade 31 is inclined so that the base 31B is positioned higher than the tip 31E (see FIG. 6), so the waste toner slides off the blade 31. Conversely, although the waste toner may be bounced back by the blade 31, the waste toner collides with the blade 31 again because the intermediate transfer belt 15B is rotating in the A direction. As a whole, the waste toner continues to move in the direction B along the longitudinal direction of the tip 31E of the blade 31 and falls into the waste toner container 33 (direction C in FIG. 5).

According to the image forming apparatus 100 according to the present embodiment described above, the intermediate transfer belt 15B is entrained around the driving roller 15D and the driven roller 15N (an example of a plurality of rollers), holds the toner and rotates, and the driving roller. A blade 31 that contacts a planar region 15P of the intermediate transfer belt 15B that does not contact the intermediate transfer belt 15B with 15D and the driven roller 15N; A linear contact portion between the blade 31 and the intermediate transfer belt 15B is inclined with respect to the rotation direction A of the intermediate transfer belt 15B. According to this configuration, the waste toner moves along the contact portion and drops into the waste toner container 33, so that the waste toner can be recovered with a low-cost and simple configuration.

Further, according to the image forming apparatus 100 according to the present embodiment, the contact portion between the blade 31 and the intermediate transfer belt 15B is straight in the longitudinal direction of the blade 31, and the waste toner container is located at both ends of the contact portion. Since it is provided below the end located on the back side in the circumferential direction, the waste toner can be collected with the blade 31 having a simple shape.

The above embodiment may be modified as follows.

FIG. 8 is a perspective view showing how the blade 31 and the waste toner container 33 according to the modification are arranged in the intermediate transfer unit 15. As shown in FIG. The distal end portion 31E of the blade 31 is formed in a V shape in which both longitudinal ends of the blade 31 are positioned deeper in the circumferential direction A than the central portion. That is, in the linear contact portion between the blade 31 and the intermediate transfer belt 15B, both ends in the longitudinal direction of the blade 31 are located on the back side in the rotation direction A from the central portion. Waste toner containers 33 are provided below both ends of the blade 31 . According to this configuration, since the waste toner is divided and carried in two directions, retention of the waste toner at the tip 31E of the blade 31 is suppressed as compared with the case where the tip 31E of the blade 31 is straight in the longitudinal direction. can do.

1 Image forming device 15B Intermediate transfer belt 15D Drive roller (roller)
15N driven roller (roller)
15P planar area 31 blade 31E tip 33 waste toner container

Claims (3)

an intermediate transfer belt that is wrapped around a plurality of rollers and rotates while holding toner;
a blade that contacts a planar region of the intermediate transfer belt where the plurality of rollers and the intermediate transfer belt do not contact;
a waste toner container for containing waste toner scraped off from the intermediate transfer belt by the blade;
An image forming apparatus, wherein a linear contact portion between the blade and the intermediate transfer belt is inclined with respect to a rotation direction of the intermediate transfer belt. The contact portion is linear in the longitudinal direction of the blade,
2. The image forming apparatus according to claim 1, wherein the waste toner container is provided below one of both ends of the contact portion that is located on the back side in the rotation direction. The contact portion has a V shape in which both ends in the longitudinal direction of the blade are positioned deeper in the circumferential direction than the central portion;
2. The image forming apparatus according to claim 1, wherein the waste toner container is provided below both ends of the contact portion.

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