JP2022175411A - Image forming apparatus - Google Patents

Abstract

To collect waste toner with a simple and low-cost configuration.SOLUTION: An image forming apparatus comprises: an intermediate transfer belt 15B that revolves while holding toner; a blade 31 that is in contact with the intermediate transfer belt 15B; a waste toner container 33; and a guide member 34 that guides waste toner to the waste toner container 33. The guide member 34 includes: a receiving port 34A that receives waste toner scraped off from the intermediate transfer belt 15B by the blade 31; a discharge port 34B that is provided below the receiving port 34A, is smaller than the receiving port 34A, and is connected with the waste toner container 33; and a hollow part 34H that has a tapered shape from the receiving port 34A toward the discharge port 34B. The waste toner received in the receiving port 34A falls into the waste toner container 33 only by the gravity.SELECTED DRAWING: Figure 7

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 includes an intermediate transfer member that holds toner and rotates, a blade that contacts the intermediate transfer member, a waste toner container, and a waste toner container. a guide member that guides the waste toner from the intermediate transfer member by the blade; and the guide member is provided below the inlet to receive the waste toner scraped off from the intermediate transfer member by the blade. The waste toner container has a small discharge port connected to the waste toner container, and a hollow portion tapering from the reception port toward the discharge port. and drops into the waste toner container.

The hollow portion may have an inclined portion, and an inclination angle of the inclined portion may be larger than an angle of repose of the toner.

The waste toner container is provided below one end of the blade in a direction intersecting the circumferential direction of the intermediate transfer member, and the inclined portion extends from the other end of the blade toward the outlet. can be slanted.

The intermediate transfer member may be an endless intermediate transfer belt wound around a plurality of rollers.

The blade contacts the intermediate transfer belt in a contact area where one of the plurality of rollers and the intermediate transfer belt contact, and the guide member has an enclosing portion surrounding the contact area and the blade. may be provided.

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. 4 is a perspective view showing how a guide member and a waste toner container are arranged in an intermediate transfer unit according to one embodiment of the present invention; FIG. 4 is a cross-sectional view of a guide member and a waste toner container according to one embodiment of the present invention; FIG. 4 is a cross-sectional view of a guide member and a waste toner container according to one embodiment of the present invention; FIG. FIG. 11 is a perspective view showing how a guide member and a waste toner container according to a modification of the embodiment of the present invention are arranged in an intermediate transfer unit; FIG. 10 is a cross-sectional view of a guide member and a waste toner container according to a modification of one embodiment of the present invention; 1 is a front view schematically showing an internal configuration of an image forming apparatus of a type different from one embodiment of the present invention; FIG.

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 drive roller 15D and a driven roller 15N, and faces the inner peripheral surface of the intermediate transfer belt 15B at a position corresponding to the photosensitive drum 11, and applies a primary transfer bias. A primary transfer roller 151 that generates a secondary transfer bias and a secondary transfer roller 152 that generates a secondary transfer bias are provided, facing the outer peripheral surface of the intermediate transfer belt 15B at a position corresponding to the drive roller 15D. 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 realized 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 guide member 34 and the waste toner container 33 are arranged in the intermediate transfer unit 15. As shown in FIG. 6 and 7 are sectional views of the guide member 34 and the waste toner container 33. FIG.

The image forming apparatus 100 includes an intermediate transfer belt 15B (an example of an intermediate transfer body) that rotates while holding toner, a blade 31 that contacts the intermediate transfer belt 15B, a waste toner container 33, and a waste toner container 33 that stores waste toner. The guide member 34 is provided with a receiving port 34A for receiving the waste toner scraped off from the intermediate transfer belt 15B by the blade 31 and below the receiving port 34A. It has a discharge port 34B connected to the waste toner container 33 and a hollow portion 34H tapered from the reception port 34A toward the discharge port 34B. It falls into the waste toner container 33 only by gravity.

[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 driving 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. 3 and 4) is an elongated plate-like member whose longitudinal direction is the left-right direction, and is attached to the outer peripheral surface of the intermediate transfer belt 15B in the contact area 15C where the driven roller 15N and the intermediate transfer belt 15B contact each other. in contact. The contact area 15C is an area in front of the center of the shaft of the driven roller 15N. 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. The blade 31 is arranged in an upright posture with the base portion 31B downward and the tip portion 31E upward. A tip portion 31E of the blade 31 is in contact with the intermediate transfer belt 15B at a position slightly lower than the center of the shaft of the driven roller 15N (see FIG. 4).

[Waste Toner Container]
The waste toner container 33 (see FIGS. 5-7) is a bottle having a receiving port 33A at the top. The waste toner container 33 is provided below the right end of the blade 31 (an example of one end of the blade 31 in the direction intersecting the winding direction A of the intermediate transfer belt 15B). 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.

[Guide member]
The guide member 34 (see FIGS. 5 to 7) includes an enclosing portion 34E, a receiving port 34A, a hollow portion 34H, an inclined portion 34S, and a discharge port 34B.

Surrounding portion 34E surrounds contact area 15C and blade 31 . Specifically, the enclosing part 34E is positioned at the top of the guide member 34 and has a receiving port 34A at its rear part. The receiving opening 34A has a size that allows the contact area 15C to be inserted therein. In the example of FIG. 6, the portion of the contact area 15C on the front side of the center of the shaft of the driven roller 15N is inserted into the receiving opening 34A. A part of the intermediate transfer belt 15B on the other side may be inserted into the receiving port 34A.

The hollow portion 34H is provided below the enclosing portion 34E, and its internal space penetrates in the vertical direction. The internal space of the hollow portion 34H communicates with the internal space of the enclosing portion 34E. A lower end portion of the hollow portion 34</b>H has a discharge port 34</b>B and is connected to the receiving port 33</b>A of the waste toner container 33 . The hollow portion 34H is composed of integrated front, rear, left, and right side plates. The front, rear, and right side plates are upright, while the left side plate is slanted. That is, the hollow portion 34H has an inclined portion 34S that is inclined from the left end side of the blade 31 toward the discharge port 34B. The inclination angle θ of the inclined portion 34S is larger than the angle of repose of the toner.

The guide member 34 may be provided with the receiving port 34A at the uppermost portion of the hollow portion 34H without the enclosing portion 34E. It is desirable that

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, waste toner remaining on the intermediate transfer belt 15B is conveyed by the intermediate transfer belt 15B (direction A in FIGS. 5 and 6), scraped off by the blade 31 in the contact area 15C (direction B in FIGS. 6 and 7), It falls on the inclined portion 34S of the hollow portion 34H. Since the inclination angle θ of the inclined portion 34S is larger than the angle of repose of the toner, the waste toner does not accumulate on the inclined portion 34S but slides down along the inclined portion 34S due to the action of gravity (see C in FIGS. 6 and 7). direction), and drops into the waste toner container 33 via the discharge port 34B and the receiving port 33A.

According to the image forming apparatus 100 according to the present embodiment described above, the intermediate transfer belt 15B (an example of the intermediate transfer body) that holds and rotates the toner, the blade 31 that contacts the intermediate transfer belt 15B, and the waste toner container. 33 and a guide member 34 for guiding the waste toner to the waste toner container 33. The guide member 34 receives the waste toner scraped from the intermediate transfer belt 15B by the blade 31, and the reception port 34A. and a discharge port 34B which is smaller than the reception port 34A and is connected to the waste toner container 33; The waste toner received in the receiving port 34A drops into the waste toner container 33 only by gravity. According to this configuration, the waste toner can be collected with a low-cost and simple configuration.

Further, according to the image forming apparatus 100 according to the present embodiment, the hollow portion 34H has the inclined portion 34S, and the inclination angle θ of the inclined portion 34S is larger than the angle of repose of the toner. can be prevented from accumulating.

Further, according to the image forming apparatus 100 according to the present embodiment, the waste toner container 33 is provided below one end of the blade 31 in the direction intersecting with the rotation direction A of the intermediate transfer belt 15B. Since 34S is inclined from the other end side of blade 31 toward discharge port 34B, waste toner container 33 and guide member 34 are other components (paper feed cassette 4, manual feed path 10T, etc.). can avoid interfering with

Further, according to the image forming apparatus 100 according to the present embodiment, the intermediate transfer member is the endless intermediate transfer belt 15B wound around the driving roller 15D and the driven roller 15N (an example of a plurality of rollers). In the image forming apparatus 100 that uses the intermediate transfer belt 15B as a transfer member, waste toner can be collected at low cost and with a simple configuration.

Further, according to the image forming apparatus 100 according to the present embodiment, the blade 31 contacts the intermediate transfer belt 15B in the contact area 15C where the driven roller 15N (one example of a plurality of rollers) contacts the intermediate transfer belt 15B. Since the guide member 34 includes the enclosing portion 34E that encloses the contact area 15C and the blade 31, scattering of waste toner can be prevented.

The above embodiment may be modified as follows.

FIG. 8 is a perspective view showing how the guide member 34 and the waste toner container 33 are arranged in the intermediate transfer unit 15. As shown in FIG. FIG. 9 is a cross-sectional view of the guide member 34 and the waste toner container 33. As shown in FIG. In this example, the waste toner container 33 is provided below the center in the left-right direction of the blade 31, and the left and right side plates of the hollow portion 34H are inclined. That is, the hollow portion 34H includes a pair of inclined portions 34S that are inclined from both end sides of the blade 31 toward the discharge port 34B. The inclination angle θ of the inclined portion 34S is larger than the angle of repose of the toner.

The waste toner is scraped off by the blade 31 in the contact area 15C (direction B in FIG. 9) and falls onto the inclined portion 34S of the hollow portion 34H. Since the inclination angle θ of the inclined portion 34S is larger than the angle of repose of the toner, the waste toner does not accumulate on the inclined portion 34S but slides down along the inclined portion 34S due to the action of gravity (D, E in FIG. 9). direction), and drops into the waste toner container 33 via the discharge port 34B and the receiving port 33A.

This modification has the advantage that the inclination angle θ of the inclined portion 34S can be increased compared to the above-described embodiment when the vertical size of the guide member 34 is the same. On the other hand, if the inclination angle θ of the inclined portion 34S is the same as in the above embodiment, the size of the guide member 34 in the vertical direction can be made smaller than in the above embodiment.

FIG. 10 is a front view schematically showing the internal configuration of an image forming apparatus 100 of a type different from the above embodiment. In the above embodiment, the paper feed cassette 4 is pulled out to the right side of the paper surface, but in the example 10, the paper feed cassette 4 is pulled out to the front side of the paper surface. In the above embodiment, the waste toner container 33 is provided closer to the paper surface than the paper feed cassette 4 so as not to interfere with the paper feed cassette 4 when the paper feed cassette 4 is pulled out. , interference between the waste toner container 33 and the paper feed cassette 4 can be avoided at any position on the left side of the paper feed cassette 4 . Therefore, this modification is suitable for the image forming apparatus 100 having the configuration shown in FIG.

In the above embodiments, an example in which the intermediate transfer member is an endless belt has been shown, but the present invention may be applied to an image forming apparatus using a drum-type intermediate transfer member.

1 image forming device 15B intermediate transfer belt (intermediate transfer body)
15D drive roller (roller)
15N driven roller (roller)
15C contact area 31 blade 33 waste toner container 34 guide member 34E enclosing portion 34A reception port 34H hollow portion 34S inclined portion 34B discharge port

Claims (5)

an intermediate transfer member rotating while holding toner;
a blade that contacts the intermediate transfer member;
a waste toner container;
a guide member for guiding waste toner to the waste toner container;
The guide member is
a receiving port for receiving the waste toner scraped off from the intermediate transfer member by the blade;
a discharge port provided below the receiving port, smaller than the receiving port, and connected to the waste toner container;
a hollow portion tapered from the inlet toward the discharge port,
An image forming apparatus, wherein the waste toner received in the receiving port drops into the waste toner container only by gravity. The hollow portion has an inclined portion,
2. The image forming apparatus according to claim 1, wherein an inclination angle of said inclined portion is larger than an angle of repose of said toner. The waste toner container is provided below one end of the blade in a direction intersecting the circumferential direction of the intermediate transfer member,
3. The image forming apparatus according to claim 2, wherein the inclined portion is inclined from the other end side of the blade toward the discharge port. 4. The image forming apparatus according to claim 1, wherein the intermediate transfer member is an endless intermediate transfer belt wound around a plurality of rollers. the blade is in contact with the intermediate transfer belt in a contact area where one of the plurality of rollers and the intermediate transfer belt contact;
5. The image forming apparatus according to claim 4, wherein the guide member includes an enclosing portion that encloses the contact area and the blade.

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