JPH1184969A - Waste toner carrying device for image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a waste toner carrying device for image forming device capable of preventing the toner from blocking in a waste toner carrying pipe. SOLUTION: This waste toner carrying device for image forming device which carries waste toner produced in a cleaner to a waste toner container is constituted of the waste toner carrying pipe 5, a rotatable waste toner carrying screw 6 arranged in the pipe 5, and a driving means for driving and rotating the screw 6. Then, projecting parts 5a continued in a waste toner carrying direction are formed on the inner surface of the pipe 5. In the case of carrying the waste toner to the waste toner container by rotating the screw 6 in the pipe 5, the screw 6 comes in contact with the inner surface of the pipe 5 in such a minute range that only the projecting part 5a formed on the inner surface of the pipe 5 abuts thereon without abutting flat thereon, so that the waste toner is carried in a state where excessive stress is not applied, and the waste toner in the pipe 5 is prevented from blocking.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waste toner conveying device for an image forming apparatus such as a copying machine or a laser beam printer (LBP).

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus, after a toner image formed on an image carrier is transferred to a transfer material, the next image forming process is started so as not to hinder the next image formation. Previously, waste toner remaining on the image carrier was removed using a cleaner.

Incidentally, a waste toner conveying apparatus employing a configuration in which waste toner in a cleaner is conveyed in the longitudinal direction of the image carrier and the waste toner falls by its own weight from a discharge port at the end of the container is provided immediately below the discharge port. A waste toner container provided in the
There is a configuration in which the waste toner is further transported from the waste toner discharge port of the cleaner to the waste toner container by a screw or the like via a transport path such as a waste toner transport pipe from the configuration of the entire apparatus.

FIGS. 9 to 11 show cross sections of a conventional waste toner conveying device. 9 to 11, only the shape and position of the waste toner conveying pipe 305 are different, and the same members are denoted by the same reference numerals. FIG. 12 shows a cross section taken along line cc of FIG.

9 to 11, reference numeral 301 denotes a photosensitive drum as an image carrier; 302, a cleaner as cleaning means; 303, a screw for discharging waste toner accumulated in the cleaner 302 to the outside of the container; A cap 305 for covering the waste toner discharge port of the cleaner 302 and guiding the waste toner to the waste toner conveying path, and 305 is a cleaner 3
02 to a waste toner container 31 described later.
The waste toner transport pipe 305 is configured to be integrated with the cap 304 or detachably attached to the cap 304.

Reference numeral 306 denotes the waste toner conveying pipe 30.
5, a waste toner conveying screw as means for conveying the waste toner in 5, a bearing 307 for rotatably supporting the waste toner conveying screw 306, a gear train 308, and a driving source 309 for driving the waste toner conveying screw 306 A motor 310 is a waste toner container for storing waste toner.

[0007]

The outer diameter of the waste toner conveying screw 306 is determined by the size of the waste toner conveying pipe 30.
5 is smaller by several mm than the inner diameter of the waste toner conveying screw 30 as shown in the sectional view of FIG.
When the contact area 6 is offset and comes into contact with the inner peripheral wall of the waste toner transport pipe 306, and the contact area between them becomes large, the stress applied to the waste toner necessarily increases, and so-called toner blocking in which the waste toner is coagulated and solidified easily occurs.

Further, the location where the gap is formed between the waste toner conveying pipe 306 and the waste toner conveying screw 306 varies depending on the direction of the bias of the waste toner conveying screw 306. In any of the systems shown in FIGS. In the vicinity immediately below the waste toner discharge port, at least a gap was formed on the lower surface of the inner wall of the waste toner transport pipe 305.

Incidentally, in the conventional waste toner conveying device, the waste toner conveying screw in the waste toner conveying pipe 305 is so arranged that the amount of waste toner conveyed is larger than the amount of waste toner discharged from the outlet of the cleaner 302. 306
In particular, in a portion vertically below the cleaner discharge port, depending on the environment in which the apparatus is operated, waste toner may accumulate inside the waste toner transport pipe 305 to cause blocking. As one of the causes, since the outer diameter of the waste toner transport screw 306 is set smaller than the inner diameter of the waste toner transport pipe 305, a layer of waste toner is formed on the lower surface of the inner wall of the waste toner transport pipe 305, The waste toner conveying screw 306 is sandwiched between the waste toner accumulated on this layer and when the waste toner is solidified due to a temperature change or the like, the load of the driving torque is increased, and the defective conveyance of the waste toner occurs. It is possible.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an obsolete toner conveying device of an image forming apparatus capable of preventing occurrence of toner blocking in a waste toner conveying pipe.

FIGS. 13 to 16 show another conventional example of a waste toner conveying device. 13 to 15 are sectional views of a conventional waste toner conveying device, and FIG. 16 is a sectional view taken along line dd of FIG.

The waste toner conveying pipe 305 shown in FIG.
6 was also straight, and a hard type screw was used as the waste toner conveying screw 306.

However, in recent years, it has become difficult to arrange the waste toner conveying pipe 305 straight in accordance with the complexity of the internal structure of the image forming apparatus main body and space saving. Therefore, in some image forming apparatuses, the waste toner transport pipe 30 of a partially curved type as shown in FIG.
5 is used, and the waste toner conveying screw 306 disposed therein is a torsion coil spring that can rotate even if it is curved.

However, when the waste toner transport screw 306 is rotated in the direction of arrow A in FIG. 16, the waste toner transport screw 306 itself rotates due to the resistance of the curved wall surface of the waste toner transport pipe 305 and the waste toner to be transported. It contracts in the center direction C.

The waste toner conveying screw 306 receives a force in the direction J opposite to the waste toner conveying direction H, and its free end is compressed. As shown in FIG. 15, the waste toner conveying screw 306 is curved. Waste toner transport pipe 3
05, it draws the longest trajectory on the inner surface of the waste toner transport pipe 305 due to the characteristics of the spring. for that reason,
It is difficult to apply a conveying force to the waste toner ta near the wall surface of the waste toner transport pipe 305. In particular, as shown in FIG. 15, the waste toner tb in the curved portion 305a of the waste toner transport pipe 305 remains without being transported. And the waste toner tends to adhere to the wall surface of the waste toner transport pipe 305. If this state continues for a long time, the stuck waste toner t
Since the waste toner further adheres to b, the waste toner carrying capacity gradually decreases, the waste toner carrying pipe 305 is clogged, and the waste toner flows back to the cleaner, adversely affecting image formation.

Conventionally, when the waste toner transport pipe is clogged, it has been necessary to clean or replace the waste toner transport pipe. However, cleaning of the waste toner transport pipe has to be carried out after removing the pipe from the apparatus main body. In addition, the cleaning worker's hands and the like become dirty due to scattering of waste toner and the like, and replacement of the pipe is costly.

Further, particularly in a high-speed / network-compatible image forming apparatus, the downtime required for cleaning and replacing the pipe causes user dissatisfaction. In particular, to repair unexpected troubles, downtime increases due to serviceman calls, investigation of causes, preparation of replacement parts, and the like.
In recent years, the accumulation speed of waste toner tends to increase with the speeding up, high volume, and multicoloring of toner used in image forming apparatuses. It is becoming more important to extend the life.

Accordingly, an object of the present invention is to provide a waste toner conveying device of an image forming apparatus which can prevent the waste toner pipe from being clogged for a long period of time without having to clean and replace the waste toner pipe. is there.

[0019]

According to one aspect of the present invention, there is provided an apparatus for transporting waste toner generated in a cleaner to a waste toner container, comprising: a waste toner transport pipe; In a waste toner transport device of an image forming apparatus, comprising: a rotatable waste toner transport screw disposed in a toner transport pipe; and a driving unit that rotationally drives the waste toner transport screw. A convex portion continuous in the waste toner transport direction or a convex portion having a predetermined length is formed.

According to a second aspect of the present invention, there is provided an apparatus for transporting waste toner generated in a cleaner to a waste toner container, comprising: a waste toner transport pipe; and a rotatable waste toner disposed in the waste toner transport pipe. In a waste toner transport device of an image forming apparatus, comprising: a transport screw and a driving unit that rotationally drives the waste toner transport screw, a bending direction of the waste toner transport pipe substantially vertically below a waste toner discharge port of the cleaner. Is set to be convex in the direction of gravity.

According to a third aspect of the present invention, there is provided an apparatus for transporting waste toner generated in a cleaner to a waste toner container, comprising: a waste toner transport pipe; and a rotatable waste toner disposed in the waste toner transport pipe. In a waste toner transport device of an image forming apparatus including a transport screw and a driving unit that rotationally drives the waste toner transport screw, a weight detection unit that detects a weight of the waste toner stored in the waste toner container is provided, A waste toner conveying pipe blockage prevention sequence is executed based on the waste toner weight detected by the weight detecting means and the input video information.

According to a fourth aspect of the present invention, in the third aspect of the present invention, the difference between the waste toner weight detected by the weight detecting means and the waste toner weight estimated based on the input video information is provided. When the number exceeds a predetermined amount, the sequence for preventing clogging of the waste toner transport pipe is executed.

According to a fifth aspect of the present invention, in the third or fourth aspect of the present invention, the waste toner transport pipe blockage prevention sequence is such that the drive unit is driven while the image forming operation is stopped to transport the waste toner transport. The screw is driven to rotate for a predetermined time.

According to a sixth aspect of the present invention, in the invention of the third, fourth or fifth aspect, the driving means is constituted by a motor capable of normal rotation and reverse rotation, and the waste toner conveying pipe is prevented from being clogged when the sequence is prevented. The toner conveying screw is reversely rotated for a predetermined time.

According to a seventh aspect of the present invention, in the third aspect of the invention, the waste toner conveying pipe clogging prevention sequence is performed based on information reported to a service person from a main body status reporting means provided in the main body of the image forming apparatus. Is performed.

Therefore, according to the first aspect of the present invention, when the waste toner transport screw rotates in the waste toner transport pipe to transport the waste toner to the waste toner container, the waste toner transport screw rotates the waste toner transport screw. Without contacting the inner surface of the pipe, only a small area of the protrusion formed on the inner surface of the waste toner transport pipe comes into contact, so that the waste toner is transported without receiving excessive stress, and the waste toner transport pipe Blocking of waste toner at the same time is prevented.

According to the second aspect of the present invention, the shape of the waste toner transport pipe in the portion where waste toner is accumulated and blocking is likely to occur, such as in the vicinity immediately below the waste toner discharge port of the cleaner, is convex in the direction of gravity. By bending so that the waste toner conveying screw is urged into the waste toner conveying pipe to the lower surface of the inner wall of the pipe, the toner layer on the inner wall of the pipe can be reliably scraped off with a simple configuration, and the waste toner conveying can be performed. Blocking of waste toner in the pipe can be reliably prevented.

According to the third aspect of the present invention, the waste toner conveying pipe clogging prevention sequence is executed based on the waste toner weight detected by the weight detecting means and the input video information. The clogging of the waste toner pipe can be prevented for a long period of time without requiring cleaning and replacement of the waste toner transport pipe.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION

[First invention] An embodiment of the first invention will be described below with reference to the accompanying drawings.

FIG. 1 is a sectional view of the waste toner conveying device according to the first invention, FIG. 2 is a sectional view taken along line aa of FIG. 1, and FIG. 3 is a perspective view of a waste toner conveying pipe.

The waste toner conveying device shown in FIG.
And a waste toner transport pipe 5 and a waste toner transport screw 6 provided in the waste toner pipe 5.
And a motor 9 as a driving means for rotating the waste toner conveying screw 6.

As shown in FIGS. 2 and 3, four projections 5a are formed on the inner surface of the waste toner transport pipe 5 in a continuous manner in the axial direction. When the waste toner t is transported by the waste toner transport screw 6 inside the waste toner transport pipe 5 configured as described above, the waste toner transport pipe 5 is formed with a plurality of protrusions 5a. Toner conveying screw 6 and waste toner conveying pipe 5
Does not come into contact with the surface, but comes into contact only at the convex portion 5a. Therefore, the waste toner t is transported from the cleaner 2 to the waste toner container 10 without being subjected to stress such as being crushed by the waste toner transport screw 6. Therefore,
Damage to the waste toner t is reduced, and blocking due to fixation and dissolution of the waste toner t in the waste toner transport pipe 5 is prevented.

If the convex portion 5a formed on the waste toner transport pipe 5 is cut off in the axial direction so as to be discontinuous, the waste toner transport screw 6 gets caught at the cut of the convex portion 5a,
Since the waste toner t attached to the waste toner conveying screw 6 is dropped by the vibration generated when the waste toner is opened, the blocking of the waste toner t in the waste toner conveying pipe 5 is more reliably prevented.

The projection 5a in the waste toner transport pipe 5 does not need to be located in the entire area of the pipe 5, but in a bent portion of the pipe 5, particularly where the waste toner t is easily subjected to stress from the waste toner transport screw 6 or the like. Even if it is provided only in the case, the effect is sufficiently exhibited. [Second invention] An embodiment of the second invention will be described below with reference to the accompanying drawings.

FIG. 4 is a sectional view of the waste toner conveying device according to the second invention, and FIG. 5 is an enlarged sectional view of a main part of the waste toner conveying device.

In FIG. 4, reference numeral 1 denotes a photosensitive drum, 2 denotes a cleaner as cleaning means, 3 denotes a screw for discharging waste toner accumulated in the cleaner 2 to the outside of the container,
Is a cap for covering the waste toner discharge port of the cleaner 2 and guiding the waste toner to the waste toner conveying path, and 5 is disposed integrally or detachably with respect to the cap 4 to remove the waste toner discharged from the cleaner 2. A waste toner transport pipe for transporting to the waste toner container 10, a waste toner transport screw 6 for transporting waste toner in the waste toner transport pipe 5, a bearing 7, a gear train 8, and a waste toner transport 9 A motor that is a driving source for driving the screw 6 to rotate,
Reference numeral 10 denotes a waste toner container for storing waste toner.

In the above configuration, the waste toner remaining on the photosensitive drum 1 after transferring the toner image to the recording sheet is
It is removed by the cleaner 2. Then, the waste toner accumulated in the cleaner 2 is discharged from the discharge port to the outside of the cleaner container by a screw 3 rotatably supported in the cleaner container.

The waste toner that falls into the waste toner transport pipe 5 provided as a waste toner transport path from near the bottom of the outlet of the cleaner 2 to the waste toner container 10 has a spring property. Waste toner conveying pipe 5 by means of the coil spring shaped waste toner conveying screw 6 having
It is conveyed while rotating and rubbing the inner wall of.

Usually, the outer diameter of the waste toner conveying screw 6 is set to be smaller than the inner diameter of the waste toner conveying pipe 5 in consideration of the variation in component dimensional accuracy and the rotational load torque. A gap is formed in the opposite portion of the screw 6 depending on the direction in which the screw 6 is offset.

Therefore, in the present embodiment, the bending direction of the waste toner transport pipe 5 at a portion where the waste toner easily accumulates, such as immediately below the waste toner discharge port of the cleaner 2, is set to be convex in the direction of gravity. . For this reason, the spring-like waste toner conveying screw 6 is urged by the spring force to the lower surface side of the inner wall surface of the waste toner conveying pipe 5, and as a result, the waste toner on the lower surface of the inner diameter of the waste toner conveying pipe 5 is reliably scraped. This can be reliably transported.

In the present embodiment, the waste toner transport pipe 5 is provided only in the vicinity of a position immediately below the waste toner outlet of the cleaner 2.
For example, even if the entire pipe 5 is protruded downward like a banana, the same effect can be obtained as long as the screw 6 is urged to the lower surface of the inner wall of the pipe 5 near immediately below the outlet. It goes without saying that you can get it.

Therefore, according to the present embodiment, the waste toner transport pipe 5 in the waste toner transport pipe 5 is bent by bending the shape of the waste toner transport pipe 5 in a portion where the waste toner easily accumulates so as to be convex in the direction of gravity. The screw 6 can be urged to the lower surface of the pipe 5, and the toner layer on the inner wall of the waste toner transport pipe 5 can be reliably scraped and transported reliably with an inexpensive configuration. [Third invention] An embodiment of the third invention will be described below with reference to the accompanying drawings.

<Embodiment 1> FIG. 6 is a sectional view of a waste toner conveying device according to a third invention, FIG. 7 is a sectional view taken along line bb of FIG. 6, and FIG. It is a flowchart shown.

In FIG. 6, reference numeral 5 denotes a waste toner conveying pipe;
Reference numeral 6 denotes a waste toner conveying screw. The waste toner conveying screw 6 is formed into a torsion coil spring shape which can rotate even if it is curved, and discharges waste toner discharged from a waste toner discharge port 14 of a cleaner (not shown). A transport path for transporting to the waste toner container is configured. 8 is a gear train,
Reference numeral 9 denotes a motor as a driving unit for driving the waste toner conveying screw 6 to rotate.

When the motor 9 is driven to rotate the waste toner transport screw 6 in the waste toner transport rotation direction (the direction of the arrow A in FIG. 7), the waste toner receives the transport force of the waste toner transport screw 6. To a waste toner container (not shown).

In the present embodiment, as shown in the flowchart of FIG. 8, the toner accumulated in the toner container within a predetermined time t detected by a waste toner weight detecting means provided in a waste toner container (not shown). X represents the waste toner weight
The waste toner weight assumed to be accumulated in the waste toner container within a predetermined time t based on the video information is represented by Y, a predetermined time t.
When the limit staying waste toner weight that can stay in the waste toner transport pipe 5 and can be transported by the waste toner transport screw 6 is Z, if the relationship of YX> Z is satisfied, the image forming apparatus main body detects this. 7, the image forming operation is stopped, and only the waste toner conveying screw 6 is rotated in the direction of arrow A in FIG.

Therefore, the waste toner remaining in the waste toner transport pipe 5 is discharged to the waste toner container. At this time, since the image forming operation is stopped, the waste toner is discharged from the upstream cleaner side. Most of the waste toner remaining in the waste toner transport pipe 5 without being transported into the toner transport pipe 5 is discharged. Therefore, the resistance that the waste toner transport screw 6 receives from the waste toner decreases, and the contracted waste toner transport screw 6 expands toward the wall surface direction of the waste toner transport pipe 5 (the direction of arrow D in FIG. 7). The waste toner remaining on the wall of 5 is scraped off, and the inner wall of the waste toner transport pipe 5 is cleaned.

As described above, in this embodiment, by adding the cleaning sequence for a fixed time t during the stop of the image formation, the cleaning and replacement of the waste toner transport pipe 5 can be performed without using any special device. Without doing so, clogging of the waste toner transport pipe 5 can be prevented for a long period of time.

Second Embodiment Next, a second embodiment of the third invention will be described.

In this embodiment, as in the first embodiment, the toner is accumulated in the toner container within a predetermined time t detected by the waste toner weight detecting means provided in the waste toner container (not shown). The waste toner weight is X, the waste toner weight assumed to be accumulated in the waste toner container within a predetermined time t based on video information is Y, and the waste toner stays in the waste toner transport pipe 5 within a predetermined time t and is discarded. When the limit stay waste toner weight that can be transported by the toner transport screw 6 is Z, the image forming apparatus main body detects this and stops the image forming operation when the relationship of YX> Z is satisfied. In this case, the motor 9 is rotated in the reverse direction to rotate the waste toner conveying screw 6 in the waste toner pipe cleaning rotation direction (the direction of arrow B in FIG. 7).

Then, the waste toner conveying screw 6 is turned in the opposite direction to the wall surface of the waste toner conveying pipe 5 (in the direction of arrow D in FIG. 7) due to the curved wall surface of the waste toner conveying pipe 5 and the resistance received from the conveyed waste toner. The waste toner remaining on the wall surface is scraped off, and the inner wall of the waste toner transport pipe 5 is cleaned.

As described above, also in this embodiment,
By adding a cleaning sequence for a certain time period t while image formation is stopped, clogging of the waste toner transport pipe 5 can be prevented for a long period of time without cleaning and replacing the waste toner transport pipe 5.

Further, according to the present embodiment, since the cleaning action on the inner surface of the waste toner transport pipe 5 is stronger than that of the first embodiment, clogging of the waste toner transport pipe 5 can be prevented more effectively. .

Third Embodiment Next, a third embodiment of the third invention will be described.

In the present embodiment, a main body status reporting unit (not shown) is provided in the main body of the image forming apparatus, and a change in the status of the main body is periodically notified to a service person by the main body status reporting unit.

In the present embodiment, the waste toner weight X, which is accumulated in the toner container within a predetermined time t detected by the waste toner weight detecting means provided in the waste toner container (not shown), Based on the video information, the waste toner weight Y which is assumed to be accumulated in the waste toner container within the predetermined time t, stays in the waste toner transport pipe 5 within the predetermined time t, and can be transported by the waste toner transport screw 6 The critical remaining waste toner weight Z is periodically reported to the service person by the body status reporting means.

Then, the serviceman who has received the report can predict an appropriate replacement time of the waste toner transport pipe 5 based on this information, so that the waste toner transport pipe 5 is clogged and a sudden trouble occurs. The serviceman can replace the waste toner transport pipe 5 during regular maintenance beforehand, minimizing downtime of the main body, and using the waste toner clogging prevention sequence described in the first and second embodiments. It is possible to deal with waste toner that cannot be cleaned.

[0058]

As is apparent from the above description, claim 1
According to the first invention described above, when the waste toner transport screw rotates in the waste toner transport pipe to transport the waste toner to the waste toner container, the waste toner transport screw comes into contact with the inner surface of the waste toner transport pipe. Contact with only a small area of the convex portion formed on the inner surface of the waste toner transport pipe, the waste toner is transported without receiving excessive stress, and blocking of the waste toner in the waste toner transport pipe is prevented. The effect of peeling is obtained.

According to the second aspect of the present invention, the shape of the waste toner conveying pipe in a portion where waste toner is accumulated and blocking is likely to occur, such as in the vicinity immediately below the waste toner discharge port of the cleaner, is convex in the direction of gravity. Since the waste toner transport screw is urged to the lower surface of the inner wall of the waste toner transport pipe by bending the waste toner transport pipe, the toner layer on the inner wall of the pipe can be reliably scraped off with a simple configuration, and the waste toner transport can be performed. The effect is obtained that the blocking of waste toner in the pipe can be reliably prevented.

According to the third aspect of the present invention, the waste toner conveying pipe clogging prevention sequence is executed based on the waste toner weight detected by the weight detecting means and the input video information. The effect is obtained that the clogging of the waste toner pipe can be prevented for a long time without requiring cleaning and replacement of the waste toner transport pipe.

[Brief description of the drawings]

FIG. 1 is a sectional view of a waste toner conveying device according to a first invention.

FIG. 2 is a sectional view taken along line aa of FIG.

FIG. 3 is a perspective view of a waste toner transport pipe of the waste toner transport device according to the first invention.

FIG. 4 is a sectional view of a waste toner conveying device according to a second invention.

FIG. 5 is an enlarged sectional view of a main part of the waste toner conveying device according to the second invention.

FIG. 6 is a sectional view of a waste toner conveying device according to a third invention.

FIG. 7 is a sectional view taken along line bb of FIG. 6;

FIG. 8 is a flowchart showing a sequence for preventing clogging of a waste toner transport pipe in the waste toner transport device according to the third invention.

FIG. 9 is a sectional view of a conventional waste toner conveying device.

FIG. 10 is a sectional view of a conventional waste toner conveying device.

FIG. 11 is a sectional view of a conventional waste toner conveying device.

FIG. 12 is a sectional view taken along line cc of FIG. 9;

FIG. 13 is a sectional view of a conventional waste toner conveying device.

FIG. 14 is a sectional view of a conventional waste toner conveying device.

FIG. 15 is a sectional view of a conventional waste toner conveying device.

16 is a sectional view taken along line dd of FIG.

[Description of Signs] 2 Cleaner 5 Waste toner transport pipe 5a Convex portion 6 Waste toner transport screw 9 Motor (drive means) 10 Waste toner container

Claims (7)

[Claims] 1. An apparatus for transporting waste toner generated in a cleaner to a waste toner container, comprising: a waste toner transport pipe; a rotatable waste toner transport screw disposed in the waste toner transport pipe; and the waste toner. In the waste toner transport device of the image forming apparatus, comprising a driving unit that rotationally drives the transport screw, a convex portion having a continuous length or a predetermined length in a waste toner transport direction is provided on an inner surface of the waste toner transport pipe. A waste toner conveying device for an image forming apparatus, wherein the toner conveying device is formed. 2. An apparatus for transporting waste toner generated in a cleaner to a waste toner container, comprising: a waste toner transport pipe; a rotatable waste toner transport screw disposed in the waste toner transport pipe; A waste toner transport device of an image forming apparatus, comprising: a driving unit that rotationally drives a transport screw; wherein a bending direction of the waste toner transport pipe in a substantially vertically lower part of a waste toner discharge port of the cleaner is convex in a gravity direction. A waste toner conveying device for an image forming apparatus, wherein the conveying device is configured to be set as follows. 3. An apparatus for transporting waste toner generated in a cleaner to a waste toner container, comprising: a waste toner transport pipe; a rotatable waste toner transport screw disposed in the waste toner transport pipe; A waste toner conveying device of an image forming apparatus comprising: a driving unit configured to rotate a conveying screw; and a weight detecting unit configured to detect a weight of the waste toner stored in the waste toner container. A waste toner transport pipe clogging prevention sequence based on the received waste toner weight and input video information; and a waste toner transport device for the image forming apparatus. 4. The waste toner conveying pipe when a difference between a waste toner weight detected by the weight detecting means and a waste toner weight estimated based on the input video information exceeds a predetermined amount. The waste toner conveying device of an image forming apparatus according to claim 3, wherein a clogging prevention sequence is executed. 5. The waste toner transport pipe blockage prevention sequence according to claim 3, wherein the drive unit is driven to rotate the waste toner transport screw for a predetermined time while the image forming operation is stopped. Or a waste toner conveying device of the image forming apparatus according to 4. 6. The waste toner conveying screw is rotated by a predetermined time during execution of the waste toner conveying pipe clogging prevention sequence, wherein the driving means is constituted by a motor capable of normal rotation and reverse rotation. 6. A waste toner conveying device of the image forming apparatus according to 4 or 5. 7. The image forming apparatus according to claim 3, wherein the sequence for preventing the waste toner transport pipe from being clogged is executed based on information reported to a service person from a main body status reporting unit provided in the main body of the image forming apparatus. Waste toner conveying device of the forming device.