JP2001134158A - Toner recycle type image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a toner consuming amount without the occurrence of a problem such as toner scattering, image density reduction, fogging or toner scattering in an image part by effectively preventing the mixture of reverse electrifying toner or paper powder, etc., into a developing device and recycling collected toner to the developing device in an image forming device by which an image is formed by a recycle system. SOLUTION: Toner left on the surface of a photoreceptor drum after toner image transfer is collected by a cleaning device and collected toner is recycled into the developing device through a toner supplying carrier pipe which incorporates a carrier spiral in the image forming device. The device is characterized in such a way that an opening/closing possible opening port communicating with a toner discarding container is arranged in the midst of the carrier pipe, the opening part is set to be opened by a fixed timing and toner passing through the pipe is caught into the toner discarding container when the opening part is opened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine, a printer,
Related to an image forming apparatus such as a facsimile,
More particularly, the present invention relates to a toner recycling type image forming apparatus in which toner collected by a cleaning device is recycled into a developing device and reused.

[0002]

2. Description of the Related Art In an image forming apparatus represented by a copying machine, the surface of a photosensitive drum is uniformly charged, and an electrostatic latent image corresponding to a document image is formed on the surface of the photosensitive drum by image exposure. The electrostatic latent image is developed to form a toner image on the surface of the photoconductor drum, and the toner image is transferred from the surface of the photoconductor drum onto a transfer material such as paper, and the transferred toner image is subjected to heat, pressure, or the like. By fixing, an image is formed.

In such an image forming apparatus, as a developer, a one-component magnetic developer composed of a magnetic toner,
A two-component magnetic developer composed of a toner and a magnetic carrier is widely used, and a developing device for performing development using such a magnetic developer usually includes a developing housing filled with a magnetic developer. The developer housing is accommodated in the developing housing so as to face the surface of the photosensitive drum. That is, the developer conveying sleeve (developing roller) has a structure in which a magnet having a plurality of magnetic poles is provided in a non-magnetic sleeve such as aluminum. A developer containing toner charged to a predetermined polarity is transported to a region (between the sleeve and the surface of the photosensitive drum), and development is performed using the charged toner.

Recently, in order to reduce toner consumption, after a toner image is transferred onto a predetermined transfer material, the toner removed from the surface of the photoreceptor by a cleaning device such as a cleaning blade is collected. Image forming apparatuses employing a system for recycling and reuse in the above-described developing apparatus are widely used.

However, in such a toner recycling type image forming apparatus, image quality such as toner scattering, reduction in image density, fogging and toner scattering in an image portion occurs during repeated image formation, resulting in high image quality. There is a problem that it is difficult to obtain an image. That is, a stirring and mixing member is accommodated in the developing device, and by stirring and mixing the developer, the toner in the developer is frictionally charged to a predetermined polarity, and the electrostatic latent toner is charged by the toner thus charged. An image is developed. In such a developer, a small amount of a reversely charged toner is contained. However, in the toner recycling type image forming apparatus described above, the amount of the oppositely charged toner in the developing device increases as the toner repeatedly circulates during the image forming process. By supplying such a reversely charged toner to the developing area, the above-described image quality deterioration occurs. Further, as the image forming process is repeated, paper dust generated from the transfer material (paper) is collected by the cleaning device, and the proportion of paper dust in the developer increases. Or the generation of the oppositely charged toner may be promoted.

In order to solve such a problem, a transport path for recycling the collected toner into the developing device is branched to a toner waste container, and a user collects the collected toner in the toner waste container by a predetermined switch. There is known an image forming apparatus configured so that the user can select whether to recycle the image forming apparatus or to recycle it in a developing apparatus (Japanese Patent Laid-Open No. 10-32).
No. 6069).

[0007]

However, in the recycle type image forming apparatus provided with the switching mechanism as described above, a user aims at high quality images.
When the discarding of the collected toner is selected, the toner consumption cannot be reduced, and when the recycling of the collected toner is selected to reduce the toner consumption, the image quality is inevitably deteriorated.

Accordingly, an object of the present invention is to provide an image forming apparatus for forming an image in a recycling system, in which the above-described mixing of the reversely charged toner and paper powder into the developing device is effectively prevented, and the collected toner is introduced into the developing device. By recycling
An object of the present invention is to provide an image forming apparatus capable of reducing toner consumption without causing problems such as toner scattering, reduction of image density, fog, and toner scattering of an image portion.

[0009]

According to the present invention, a toner image is formed by developing an electrostatic image formed on the surface of a photosensitive drum with a magnetic developer filled in a developing device. The image is transferred onto a predetermined transfer material, and the toner remaining on the surface of the photosensitive drum after the transfer of the toner image is collected by a cleaning device, and the collected toner is passed through a toner feeding transport tube having a built-in transport spiral. In the image forming apparatus that is recycled into the developing device, an openable and closable opening communicating with the toner waste container is provided in the middle of the toner feeding conveyance pipe, and the opening is opened at a predetermined timing. Wherein the toner passing through the toner feeding conveyance pipe is collected in a toner waste container when the opening is opened. It is.

According to the present invention, an opening which is opened at a predetermined timing is provided in a toner feeding and conveying pipe for recycling toner collected from the surface of a photosensitive drum by a cleaning device including a cleaning blade into a developing device. Is a remarkable feature. That is, when the opening is opened, the collected toner passing through the toner feeding conveyance pipe is introduced into the toner waste container through the opening, and when the opening is closed, the toner feeding conveyance is performed. The collected toner passing through the tube is recycled as it is into the developing device.

When the photosensitive drum is being driven and rotated during non-image formation, for example, the main switch of the image forming apparatus is set to O
When set to N, or when the preheating of the fixing device is released after auto-shut-off, the running-in operation (aging)
For this, the photosensitive drum is driven and rotated. There is a certain time lag between the end of the image formation and the end of the drive rotation of the photoconductor drum, and the photoconductor drum rotates for a certain time after the end of the image formation. Further, when image formation is repeatedly performed to form images on a plurality of transfer papers, respectively, from when an image is formed on a predetermined transfer paper to when image formation is performed on the next transfer paper (image formation). Even during the cycle), the photosensitive drum is driven and rotated. As described above, when the photosensitive drum is being driven and rotated during non-image formation, the oppositely charged toner charged to the polarity opposite to the normal charging polarity is collected by the cleaning device. That is, at the time of non-image formation, such as at the end of image formation or during an image forming cycle, the normally charged toner is less likely to transfer onto the photosensitive drum surface relative to the developing roller in the developing device. Is maintained at such a potential that the easily oppositely charged toner easily migrates to the surface of the photosensitive drum. For example, when development is performed using positively charged toner, the surface of the photosensitive drum is maintained at a potential higher by about 200 V than the developing roller. For this reason,
At the end of image formation, the oppositely charged toner easily adheres to the surface of the photoconductor drum. As a result, during the above-mentioned smoothing operation (during aging), during rotation of the drum after completion of image formation, or during continuous operation. The toner collected by the cleaning device during the image forming cycle when the image is formed is mainly of the oppositely charged toner.

Accordingly, in the present invention, the opening of the toner feeding and conveying pipe is opened at the same time that the toner collected from the photosensitive drum during the non-image formation passes through the conveying pipe, so that the oppositely charged toner is removed. The toner can be selectively collected in the toner waste container. Further, since the paper powder is generally negatively charged, when a positively charged toner is used as the toner in the developer, the paper dust is collected together with the oppositely charged toner in a toner waste container. On the other hand, when a negatively charged toner is used as the toner in the developer, the paper dust is supplied into the developing device together with the regular charged toner. In this case, the paper dust is mixed with the regular toner. Since they are charged to the same polarity, the influence on the image is extremely small, and there is almost no problem.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to specific examples shown in the accompanying drawings. FIG. 1 shows an outline of the overall arrangement of the image forming apparatus of the present invention, and FIGS. 2 and 3 are views showing the structure of a toner feeding transport tube configured according to the present invention.

In FIG. 1, in this image forming apparatus, a main charging device 2, an exposure mechanism 3, a developing device 4, a transfer device are provided around a photosensitive drum 1 rotatably provided in the direction of the arrow in FIG. 5, the static elimination device 6, the cleaning device 7
The photosensitive drum 1 is arranged in this order along the rotation direction of the photosensitive drum 1, and paper or O 2 is placed between the photosensitive drum 1 and the transfer device 5.
A transfer material 10 such as an HP film is passed through, and a fixing device 11 is provided on a discharge path of the transfer material 10.

As the photosensitive drum 1, an inorganic photosensitive drum in which a photosensitive layer such as selenium or amorphous silicon is provided on a conductive base roller such as aluminum, or a charge generating agent or a charge transporting agent in a binder resin. An organic photosensitive drum provided with an organic photosensitive layer in which is dispersed is used. As the main charging device 2, there is a roller-type contact charging device, but generally, a corona charger is used, and the main charging device 2 causes the surface (photosensitive layer) of the photosensitive drum 1 to change the type of the photosensitive layer. , And is uniformly charged to a predetermined polarity. At this time, the main charging potential of the photoreceptor surface is usually 200 to 1000 V (absolute value). Next, the image exposure mechanism 3 irradiates the surface of the photoreceptor drum with dot light such as a laser beam corresponding to the original by reflected light of the original or an electric signal from a computer or the like. A latent image is formed, the electrostatic latent image is developed by the developing device 4, and a toner image 15 is formed on the surface of the photosensitive drum 1. The transfer device 5 generally includes a transfer charger 5a and a separating charger 5b, and the back surface of the transfer material 10 introduced between the transfer device 5 and the photosensitive drum 1 is transferred to the toner by the transfer charger 5a. The toner image 15 is transferred onto the transfer material 10 by an electrostatic attraction between the charge and the toner image 15 to form a transfer toner image 16. At the same time as the toner image 16 is formed, the transfer material 1 is charged with an alternating current by the separation charger 5b.
0 is quickly separated from the surface of the photosensitive drum 1. Note that a transfer roller can be used as the transfer device 5, and in this case, a transfer material separating device such as the separating charger 5b is not required.

The transfer material 10 having the transfer toner image 16 is
The transfer toner image 16 is conveyed to the fixing device 11 and is fixed on the surface of the transfer material 10 by heat, pressure or the like. On the other hand, after the toner image 15 is transferred onto the transfer material 10, the surface charge of the photosensitive drum 1 is removed by light irradiation by the charge removing device 6. Further, the toner remaining on the surface of the photosensitive drum 1 is scraped and collected by the cleaning device 7 having a cleaning blade or the like, and the next image forming process is performed. The toner collected in the cleaning device 7 is
The toner is conveyed to the developing device 4 along the path indicated by reference numeral 25 by the toner feeding conveyance pipe 20, and is reused.

In the above-described image forming apparatus, the developing device 4 includes a developing housing 30 filled with a magnetic developer, and a developer conveying sleeve (developing roller) 31 is provided so as to face the photosensitive drum 1. (The distance between the developing roller 31 and the drum 1 is generally 0.3 to 1.
About 0 mm). The developing roller 31 has a magnet having a plurality of magnetic poles fixed inside, and conveys the developer in the form of a magnetic brush by rotation of a sleeve. For example, as shown in FIG. 1, the developing roller 31 rotates in the opposite direction to the photosensitive drum 1 (in the region facing the drum 1, the developing roller 31 moves in the same direction as the drum 1, that is, moves downward from above. The charged toner is conveyed to a region (developing region) facing the photoreceptor drum 1 in the form of a magnetic brush 33 adjusted to a predetermined spike length by the spike blade 32,
The electrostatic latent image is developed by the charged toner.

As the developer, any of a two-component developer composed of a magnetic carrier and an insulating toner and a one-component developer composed of a magnetic toner can be used. Further, a plurality of spirals or paddles 35 are provided in the developing housing 30 at an interval from the developing roller 31 so as to circulate and agitate the developer along the axis of the developing roller 31. It has become. By such circulating feeding and stirring, the toner uniformly mixed and frictionally charged to a predetermined polarity is conveyed in the form of a magnetic brush 33, and the toner causes the electrostatic latent image formed on the surface of the photosensitive drum 1 to be transferred. After the development, the toner image 15 is formed on the surface of the photosensitive drum 1.
Is formed. Toner, ie, toner image 15
The charge polarity of the photosensitive drum 1 is opposite to the charge polarity of the surface of the photosensitive drum 1 when image formation is performed by so-called regular development, and is opposite to the charge polarity of the surface of the photosensitive drum 1 when image formation is performed by reverse development. It has the same polarity as the charging polarity. In developing, the photosensitive drum 1 and the developing roller 31 are generally used.
(Normally, about 100 to 300 V in absolute value in normal development, and about 300 to 700 V in absolute value in reverse development).

In the image forming apparatus of the present invention, a toner waste container 40 is provided below the toner feed / conveyance pipe 20 provided in the circulation path 25 of the collected toner. Through a predetermined opening (not shown in FIG. 1) provided in the transport pipe 20, the collected toner is introduced from the transport pipe 20 into the toner waste container 40. That is, the opening is provided so as to be openable and closable so as to be opened at a predetermined timing. As described above, when the photosensitive drum is being driven and rotated during non-image formation, for example, (1) When the main switch of the image forming apparatus is turned ON or when the preheating of the fixing apparatus is canceled after the automatic shut-off, the preparatory operation (aging) is performed. (2) The drive rotation of the photosensitive drum after the completion of image formation Until the end of (3)
In the case where image formation is repeatedly performed, from the time when an image is formed on a predetermined transfer paper to the time when an image is formed on the next transfer paper (between two successive image formation cycles) In (1), when the toner collected by the cleaning device passes through the opening provided in the toner feed / conveyance pipe 20, the timing is adjusted and the opening is opened, whereby the above (1) to (3) can be achieved. The sometimes collected toner is introduced into the toner waste container 40.

After completion of image formation or during an image formation cycle in which image formation is performed continuously, the surface of the photosensitive drum is held at a potential at which reversely charged toner is likely to adhere. The toner collected in the cases (1) to (3) is mainly composed of the oppositely charged toner. Therefore, by opening the opening at the timing as described above and closing the opening when toner collected during the image forming cycle is transported, the oppositely charged toner can be selectively discarded. It can be collected in the container 40. Therefore, according to the present invention, the consumption of the toner is minimized by recycling the collected toner, and at the same time, the reversely charged toner is selectively collected and prevented from being mixed into the developing device.
The image quality is effectively prevented from being degraded by the oppositely charged toner, and a high quality image can be obtained.

In the present invention, the opening of the opening of the toner feeding / conveying tube 20 is opened when any of the above (1) to (3) or all of the above (1) to (3) is used. It is performed at the timing of being collected in the toner waste container 40, but at least a smoothing operation (aging) as in (1).
It is preferable that the toner collected at the time of (1) is collected in the toner waste container 40. This is because the toner (reversely charged toner) collected at this time is the largest.

The opening timing of the opening of the toner feed / conveyance pipe 20 is such that the collected toner passes through the opening of the toner feed / conveyance pipe 20 from the time when a predetermined operation (for example, turning on a main switch) is performed. By measuring the time lag up to, it can be easily determined.

In the present invention described above, paper dust can be collected in the toner waste container 40 together with the oppositely charged toner, particularly when a positively charged toner is used as the developer. That is, since the paper dust generated from the transfer paper 10 is generally charged to a negative polarity, when a positively charged toner is used as a developer, it exhibits the same behavior as the oppositely charged toner. When a negatively charged toner is used, the paper dust is
Since the toner has the same behavior as the negatively charged toner, the toner is not collected in the toner waste container 40 but is recycled in the developing device 4. However, the paper dust forms an image together with the normally charged toner (negatively charged toner), and is embedded in the transfer toner image on the transfer paper by fixing. Therefore, the presence of paper dust is hardly observed from the outside, and when the negatively charged toner is used as the developer, there is almost no problem even if the paper dust is recycled into the developing device 4.

In the present invention, the structure of the opening provided in the toner feeding / conveying tube 20 is not particularly limited as long as it can be opened and closed at a predetermined timing, and various structures can be adopted. For example, an opening of an appropriate size can be provided in the lower wall of the toner feed / conveyance pipe 20, and this opening can be closed by an openable / closable shutter, and the toner feed / conveyance pipe 20 can be opened / closed as a double wall structure. A simple opening can also be formed. 2 and 3 show an example of the toner feed / conveyance pipe 20 in which such an opening is formed.

Referring to FIG.
Has a feed spiral 50 inside, and the toner collected from the photosensitive drum 1 is introduced into the toner feed / conveyance pipe 20 by a spiral 51 provided in the cleaning device 7, and the feed spiral 50 is provided. Feed spiral 52 for feeding toner into the developing device
To be introduced above. An opening 55 is formed in the lower side wall of the toner feed / conveyance pipe 20, and the toner waste container 40 is disposed below the opening 55.

The opening 55 can be opened and closed by a shutter 60, and the opening and closing of the shutter 60 is controlled by a solenoid 61. That is, the shutter 60 is provided with a spring 65
The shutter 60 is normally slidably attached to the projection 66 by a spring 65 so as to close the opening 55. The shutter 60 is provided with an engagement piece 68, and the solenoid 61 includes a rod 70 urged by a spring 66 into an extended state. One end of a plate 71 is rotatably attached to the tip of the rod 70. A long hole 71a is formed at the other end of the plate 71, and an engaging piece 68 provided on the shutter 60 is engaged with the long hole 71a.

Therefore, when the power supply of the solenoid 61 is turned on, the rod 70 contracts and the plate 71 rotates.
As a result, the elongated hole 71a and the engaging piece 6
2, the shutter 60 slides to the right in FIG. 2 to open the opening 55, and the collected toner is collected in the toner waste container 40 through the opening 55. on the other hand,
When the power of the solenoid 61 is turned off, the rod 70 returns to the extended state by the spring 66, and the shutter 60
Is slid to the left in FIG. 2 by the spring 65, and the opening 55 is closed again. In this state, the collected toner is recycled into the developing device 4 without being collected in the toner waste container 45. in this way,
In the toner feed / conveyance pipe 20 shown in FIG. 2, by controlling the solenoid 61 to be ON-OFF at a certain timing, the collected toner mainly composed of the oppositely charged toner can be selectively collected in the toner waste container 40. it can.

The toner feeding and conveying pipe 20 shown in FIG.
FIG. 3A shows a perspective view of the transfer tube 20, and FIG. 3B shows a side of a portion of the transfer tube 20 where an opening is formed. A cross section (AA cross section) is shown together with the toner waste container 40.

As is apparent from FIG. 3, the toner feed / conveyance pipe 20 is composed of an inner cylinder 80 provided with a feed spiral 50 therein and an outer cylinder 81 rotatably provided with respect to the inner cylinder 80. Is formed. That is, the toner collected from the surface of the photosensitive drum 1 is introduced into the inner cylinder 80 by the spiral 51 provided in the cleaning device 7 shown in FIG. By supplying the collected toner to a feeding spiral 52 for feeding the toner into the developing device 4 shown in FIG. 2, the collected toner is recycled into the developing device 4.

As shown in FIG. 3B, the inner cylinder 8
A first opening 85 is formed in a lower part of the outer cylinder 81, and a second opening 86 is formed in the outer cylinder 81. That is, as shown in FIG. 3B, the first opening 85 and the second opening
When the opening 86 does not overlap with the opening 86, the collected toner is fed through the inner cylinder 80 and is conveyed by the spiral 50. On the other hand, when the outer cylinder 81 rotates and the first opening 85 and the second opening 86 are overlapped with each other, the collected toner introduced into the inner cylinder 80 passes through these openings 85 and 8.
6 and the toner waste container 4 disposed on the lower side
It will be collected within 0.

In order to control the rotation of the outer cylinder 81 as described above, a drive gear 90 is provided outside the outer cylinder 81 as shown in FIG. On the outer surface of the outer cylinder 81, teeth 91 that mesh with the drive gear 90 are formed. That is, by rotating the drive gear 90, the outer cylinder 81 rotates, and as shown in FIG. 3B, the first opening 85 formed in the inner cylinder 80 and the outer cylinder 81 are connected to each other. The formed second opening 86 overlaps and the collected toner is collected in the toner waste container 40,
Next, when the drive gear 90 is inverted, the outer cylinder 8 is rotated.
1 is reversed, the first opening 85 is closed by the wall of the outer cylinder 81, and the collected toner is recycled into the developing device 4.

As described above, the toner feeding and conveying pipe 2 shown in FIG.
According to 0, the rotation of the drive gear 90 is controlled at a constant timing using a drive motor (not shown),
The collected toner mainly composed of the oppositely charged toner can be selectively collected in the toner waste container 40.

In the above-described present invention, the toner is developed in the aging operation performed when the main switch of the image forming apparatus is turned on or when the preheating of the fixing device is canceled after the automatic shutoff. A bias voltage in a direction opposite to the direction can be applied between the photosensitive drum 1 and the developing roller 31, whereby adhesion of the charged toner to the photosensitive drum 1 in the aging mode is effectively suppressed. Thus, unnecessary toner consumption can be effectively suppressed. That is, in the aging mode, the oppositely charged toner easily adheres to the surface of the photosensitive drum 1, and when the above bias voltage is applied,
This tendency becomes more remarkable. However, according to the present invention, the oppositely charged toner adhered to the surface of the photosensitive drum 1 at this time is collected in the toner waste container 40, so that the oppositely charged toner may be introduced into the developing device 4. Therefore, it is possible to effectively avoid the deterioration of the image quality due to the execution of the aging mode.

[0034]

According to the present invention, by collecting the collected toner in the toner waste container at a certain timing, the oppositely charged toner and paper powder can be selectively collected in the toner container. As a result, it is possible to effectively prevent the reversely charged toner and paper powder from being mixed in the developing device. Therefore, in the image forming apparatus of the present invention, the toner consumption is reduced as much as possible by recycling the collected toner into the developing device, and at the same time, toner scattering, reduction of image density, fog,
Without lowering image quality such as toner scattering in the image area,
High-quality images can be stably obtained.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an outline of an overall arrangement of an image forming apparatus according to the present invention.

FIG. 2 is a diagram illustrating an example of a structure of a toner feeding conveyance tube configured according to the present invention.

FIG. 3 is a diagram showing another example of the structure of the toner feeding transport tube configured according to the present invention.

[Explanation of symbols]

1: photosensitive drum 4: developing device 10: transfer material 7: cleaning device 20: toner feeding / conveying tube 40: toner waste container 50: feeding spiral 55: opening 60: shutter 61: solenoid 80: inner cylinder 81: outer cylinder 85 : First opening 86: second opening 90: drive gear 91: tooth

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Masahiro Tsutsumi 1-2-28 Tamatsukuri, Chuo-ku, Osaka-shi Inside Mita Kogyo Co., Ltd. (72) Inventor Noriyuki Sakata 1-2-28 Tamatsukuri, Chuo-ku, Osaka-shi Inside Mita Kogyo Co., Ltd. (72) Inventor Eiji Tanmura 1-2-28 Tamatsukuri, Chuo-ku, Osaka-shi Inside Mita Kogyo Co., Ltd. (72) Inventor Jou Nanjo 1-2-28 Takuma-zo, Chuo-ku, Osaka Mita Muko F-term (reference) in 2K027 DA32 DD03 EE02 EF09 HB12 2H034 CA02 CA04 CB01 2H077 AA14 AA18 AA25 AA37 AB02 AC02 AD06 AD35 EA03 EA13 GA17

Claims (7)

[Claims] An electrostatic image formed on the surface of a photosensitive drum is developed with a magnetic developer filled in a developing device to form a toner image, and the toner image is transferred onto a predetermined transfer material. At the same time, in an image forming apparatus in which the toner remaining on the surface of the photosensitive drum after the transfer of the toner image is collected by a cleaning device, and the collected toner is recycled into the developing device through a toner feeding conveying pipe having a built-in conveying spiral. In the middle of the toner feeding conveyance pipe,
An openable and closable opening communicating with the toner waste container is provided, and the opening is set so as to be opened at a fixed timing. When the opening is opened, the toner feeding conveyance pipe is closed. An image forming apparatus, wherein the passing toner is collected in a toner waste container. 2. The image forming apparatus according to claim 1, wherein the opening is opened at a timing at which toner collected from the surface of the photosensitive drum during non-image formation is collected in the toner waste container. 3. The image forming apparatus according to claim 2, wherein the opening is opened at a timing when the toner collected by the cleaning device during the smoothing operation of the photosensitive drum is collected in the toner waste container. apparatus. 4. The opening portion is opened at a timing at which toner collected from the surface of the photosensitive drum after the completion of image formation and before the rotation of the photosensitive drum stops is collected in the toner waste container. The image forming apparatus according to claim 2, wherein 5. The image forming apparatus according to claim 1, wherein when the image forming cycle is repeatedly performed, the toner collected from the surface of the photosensitive drum during the image forming cycle is collected in the toner waste container. Claim 2 which is released
An image forming apparatus according to claim 1. 6. The image according to claim 1, wherein the opening is formed in a lower wall of the toner feeding conveyance tube, and the opening is closed by a shutter that is opened at a predetermined timing. Forming equipment. 7. The toner feeding / conveying pipe has an inner cylinder accommodating a conveying spiral and having a first opening on a lower side, and a second opening provided rotatably with respect to the inner cylinder. And having an outer cylinder having a double wall structure, wherein the outer cylinder rotates at a certain timing,
The image forming apparatus according to claim 1, wherein the second opening overlaps the first opening, and toner conveyed in the inner cylinder is collected in the toner waste container.