JP2001109348A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device adopting a toner collection system and a recycle system with simple constitution. SOLUTION: Since an opening 27 is blocked in a state where a toner collection tank 15 is not mounted, toner discharged from a cleaning device 6 and transported through a toner transportation path 23 is not transported to the toner collection tank 15 but is transported to a developing device 5. When the toner collection tank 15 is mounted, the opening 27 is opened and the opening 27 is overlapped with the port 36 of the toner collection tank 15, then toner discharged from the cleaning device 6 and transported through the toner transportation path 23 is transported to the toner collection tank 15 and toner is accumulated in the toner collection tank 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic copying type image forming apparatus for recording an image on a sheet using toner.

[0002]

2. Description of the Related Art In an electrostatic copying type image forming apparatus, for example, an electrostatic latent image is formed on a drum-shaped photosensitive member, and this electrostatic latent image is developed into a toner image by a developing device. The image is formed by being transferred to the surface. The image forming apparatus further includes a cleaning device for removing residual toner on the surface of the photoconductor.

[0003] In this image forming apparatus, a toner recovery system is generally employed in which toner discharged from a cleaning device is collected in a toner recovery tank and collected and discarded. However, the toner discharged from the cleaning device is sent to a developing device. There is also known a recycle type image forming apparatus which conveys and reuses it for image formation. The image forming apparatus employing this recycling method can reduce the toner cost because the toner can be reused.However, since the recovered toner is often inferior in chargeability and contains fine paper powder, it is used. The image quality of the toner image is slightly deteriorated as compared with the image forming apparatus employing the toner collection method. As described above, the recycling method has advantages and disadvantages.
The image forming apparatus is selected according to the user's preference whether to give priority to cost. In recent years, user demands have been diversified, and it is preferable that one image forming apparatus can appropriately select a toner collection method or a recycling method.

Therefore, conventionally, there has been proposed an image forming apparatus in which a single image forming apparatus can appropriately select a toner collecting method or a recycling method. As this image forming apparatus, for example, there is one described in Japanese Patent Application Laid-Open No. Hei 10-326069. In this image forming apparatus, a toner conveying path for the toner collecting tank communicating with the toner collecting tank and a toner conveying path for recycling communicating with the developing device are arranged in parallel. A spiral for toner conveyance is attached to each toner conveyance path. Each toner conveying path is provided with a toner receiving portion provided with an opening at a part of the upper surface, and each toner receiving portion is partitioned by a partition wall having an opening.

[0005] The toner discharged from the toner discharge port of the cleaning device falls into the toner receiving portion of the toner conveying path for the toner collecting tank, and a part of the toner accumulated in the toner conveying path for the toner collecting tank is partially removed from the partition wall. The toner flows into the recycling toner transport path through the opening. By rotating the spiral on the toner collection tank side,
The toner stored in the toner recovery tank toner transport path is transported to the toner recovery tank, and when the spiral on the recycle side is rotated, the toner stored in the recycle toner transport path is transported to the developing device. Therefore,
It is possible to switch between the toner collection method and the toner recycling method depending on which spiral is rotated.

[0006]

However, in the conventional image forming apparatus, the toner does not move smoothly from the toner conveyance path for the toner collection tank to the toner conveyance path for recycling. In particular, when the humidity is high, the fluidity of the toner is poor, and the toner does not flow into the toner transport path for recycling. This problem can be solved by providing a mechanism for flattening the toner accumulated above the partition wall,
This complicates the configuration.

Further, since the toner flows through the space above the partition wall into the toner conveying path for recycling, the toner is accumulated in the toner conveying path for the toner collection tank, and the toner is collected. When the system is adopted, all of the toner discharged from the cleaning device cannot be effectively used. SUMMARY OF THE INVENTION It is an object of the present invention to provide an image forming apparatus having a simple configuration and capable of adopting both a toner collecting method and a recycling method.

[0008]

Means for Solving the Problems and Effects of the Invention (1)
An image forming apparatus according to the present invention includes a photoreceptor on which an electrostatic latent image is formed, a developing device for developing the electrostatic latent image on the photoreceptor surface into a toner image, and removing residual toner on the photoreceptor surface. Cleaning device, a toner conveying path communicating the cleaning device and the developing device, an opening formed in the middle of the toner conveying path, and a cleaning device provided in relation to the opening and removed by the cleaning device. An opening is opened when the toner collection tank is mounted on the toner collection tank mounting portion for mounting a toner collection tank for collecting toner, and the opening is opened when the toner recovery tank is not mounted on the toner collection tank. And an opening / closing mechanism for closing the image forming apparatus.

According to the present invention, when the toner collection tank is not mounted, the opening formed in the toner conveyance path is closed, and the toner discharged from the cleaning device is not conveyed to the toner collection tank, and is not developed. Conveyed to the device.
Further, when the toner collection tank is mounted, the toner discharged from the cleaning device is transported to the toner collection tank because the opening is opened. Therefore, depending on whether the toner collection tank is mounted or not, the toner recovery method and the recycling method can be appropriately selected.
Accordingly, it is possible to provide an image forming apparatus that can select both the toner collection method and the recycling method with a simple configuration. (2) The toner transport path has a rotary shaft extending in the same direction as the toner transport path and a spiral spiral blade protruding from the rotary axis. It is preferable that a toner transport unit that transports the residual toner to the toner recovery tank and transports the overflowed toner to the developing device be provided. In this case, the toner discharged from the cleaning device can be favorably conveyed to the toner collection tank or the developing device.

Further, it is preferable that the transport spiral be one which is linked to the rotation of the transport spiral provided in the cleaning device. In this case, the motor and the like can be shared, and an extra drive source is not required. (3) Further, it is preferable that the toner conveying path is inclined downward toward the developing device, and the toner collecting tank can be mounted below the opening (claim 3). In this case, the toner discharged from the cleaning device can be favorably conveyed to the toner collection tank or the developing device by gravity.

[0011]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a schematic longitudinal sectional view for explaining the internal structure of the image forming apparatus 1 according to the present invention. The image forming apparatus 1 is a multifunctional device that is basically used as a copying machine and can also be used as a printer or a facsimile.

The image forming apparatus 1 has a photosensitive drum 3 in a housing 2. Around the photosensitive drum 3,
A main charger 4 for keeping the surface of the photosensitive drum 3 at a constant potential; a developing device 5 for developing an electrostatic latent image formed on the surface of the photosensitive drum 3 into a toner image; A cleaning device 6 for removing toner remaining on the surface is provided. In this embodiment, the photosensitive drum 3, the main charger 4, the developing device 5, and the cleaning device 6 are integrated as an image forming unit 7, and are detachably mounted in the housing 2. Further, a toner cartridge 8 for supplying toner to the developing device 5 is detachably attached to the developing device 5 of the image forming unit 7.

A paper feed tray 9 is accommodated in the main body housing 2. The paper P put in the paper feed tray 9 is 1
Each sheet is taken out and transported between the photosensitive drum 3 of the image forming unit 7 and the transfer roller 10 in contact with the photosensitive drum 3. The toner image on the surface of the photoconductor drum 3 is transferred to the paper P by passing the paper P between the photoconductor drum 3 and the transfer roller 10.

The sheet P on which the toner image has been transferred is placed on a fixing device 1.
It is transported to 1. The fixing device 11 includes a pair of rollers 12, and the sheet P passes between the pair of rollers 12 so that the toner image transferred to the sheet P is fixed on the sheet P. The sheet P on which the toner image has been fixed is conveyed to the sheet discharge tray 13. FIG. 2 is a perspective view illustrating a configuration of the image forming unit 7.

On the bottom surface of the housing 14 on one end 7a side of the image forming unit 7, a toner collecting tank mounting portion 16 for mounting a toner collecting tank 15 for collecting the toner discharged from the cleaning device 6 is provided. . FIG. 2 shows a mounted state of the toner collection tank 15.
FIG. 3 is a cross-sectional view of a main part around the image forming unit 7 in a state where the main body is mounted in the housing 2 as viewed from above.

In the housing 55 of the developing device 5, a developing roller 17 which comes into contact with the photosensitive drum 3, an auxiliary roller 18 which comes into contact with the developing roller 17, and a supply for supplying toner to the developing roller 17 and the auxiliary roller 18 A part 53 is provided. The supply unit 53 includes the photosensitive drum 3
And two developing conveyance spirals 19 extending in parallel with each other.

A cleaning conveying spiral 22 is mounted in the housing 20 of the long cleaning device 6, and one end 22 b of a rotating shaft 22 a protrudes from one end 3 a of the photosensitive drum 3. A toner outlet 21 is formed on the bottom surface of the housing 20 of the cleaning device 6 on one end 20a side. On one end 7 a side of the image forming unit 7, a toner conveying path 23 that communicates the toner discharge port 21 of the cleaning device 6 with the developing device 5 is provided. A rotating shaft 25 extending in the same direction as the toner conveying path 23 extends in the toner conveying path 23.
And a transfer spiral 24 having a spiral spiral blade 26 projecting from the rotation shaft 25.

A branch path 50 (see FIG. 8) extending downward is formed at an intermediate portion of the toner conveying path 23, and an opening 27 is formed at a lower end of the branch path 50. When the toner collection tank 15 is mounted, the toner collection tank 15
Is disposed below the opening 27. On the other end 2 b side of the housing 2 of the image forming apparatus 1, there is a drive mechanism 56 for rotatingly driving the photosensitive drum 3, various rollers 17, 18, and various transport spirals 19, 22, 24. The drive mechanism 56 includes the motor 28 and a plurality of gears linearly combined along the housing 2.

The image forming unit 7 includes gears 30 and 3 connected to the developing roller 17, the auxiliary roller 18, and the rotating shafts of the two developing transport spirals 19 and 19, respectively.
1, 32, 33, and these gears 30,
Reference numerals 31, 32, and 33 are driven by the driving mechanism 56, and are linearly combined on the other end 7b side of the image forming unit 7. Further, a gear 34 driven by a driving mechanism 56 is provided on the other end 22c side of the rotating shaft 22a of the cleaning transport spiral 22.

Further, a gear 57 is provided on one end 22b side of the rotating shaft 22a of the cleaning transport spiral 22. The gear 57 is connected to the gear 35A through gears 58 and 59. These gears 57,
58 and 59 are linearly combined on one end 7a side of the image forming unit 7. The gear 35A
It engages with a gear 35B provided on the rotating shaft 25 of the transport spiral 24.

With the image forming unit 7 mounted in the housing 2 of the image forming apparatus 1, the gears of the drive mechanism 56 and the gears 30 and 34 are connected. By these,
The gear 29 connected to the motor 28 includes gears 30, 31,
32, 33 and the gear 34, and the gear 35B is geared with the gear 57.

When the motor 28 is driven, the developing conveying spiral 19 and the cleaning conveying spiral 22 rotate, and the toner supplied from the toner cartridge 8 into the developing device 5 is rotated by the rotating developing conveying spiral 19 in FIG. While being transported in the direction of arrow B, the residual toner on the photosensitive drum 3 removed by a cleaning blade or the like (not shown) is transferred to the toner discharge port 21 side by the cleaning transport spiral 22 of the cleaning device 6 as shown by arrow C. Conveyed.

The cleaning transport spiral 22
Of the transport spiral 2 in the toner transport path 23 with the rotation of
The rotation shaft 25 rotates, and the toner discharged from the toner discharge port 21 is conveyed to the developing device 5 in the direction of arrow E. As described above, the cleaning transport spiral 22 and the transport spiral 24 can be driven by the single motor 28, so that an extra drive source for rotating the transport spiral 24 is not required.

FIG. 4 is a perspective view of the toner recovery tank 15. The toner collection tank 15 has an opening 36 penetrating the upper surface thereof. FIG. 5 shows the toner collection tank mounting section 1.
6 is a bottom view of the image forming unit 7 for explaining the image forming unit 6. FIG. The toner collection tank mounting section 16 includes a shutter 38 that can be slid in the horizontal direction, and
And a spring 39 for urging rightward. Also,
A protrusion 40 is provided at the left end of the shutter 38 shown in FIG. Since the shutter 38 is biased, the opening 27 is covered by the shutter 38 when the toner collection tank 15 is not mounted, as shown in FIG. A substantially rectangular through hole 41 is formed in the shutter 38. When the shutter 38 is slid to the left as shown in FIG. 5B, the opening 27 and the through hole 41 of the shutter 38 are separated. It will overlap. Thereby, the opening 27
Is opened.

FIGS. 6 and 7 show the toner recovery tank 15.
FIG. 6 is a diagram illustrating a state in which is mounted on a toner collection tank mounting section 16. As shown in FIG.
Is mounted by sliding in the direction of arrow D. When mounted on the toner recovery tank mounting section 16, the toner recovery tank 15 is held by other components from below. For this reason, the toner collection tank 15
With the image forming unit 7 mounted in the housing 2, the image forming unit 7 can be mounted and fixed to the toner collection tank mounting portion 16.

An elastic claw 42 is provided at one end 16a of the toner collecting tank mounting portion 16. The elastic claw 42 includes an operation unit 51, and by operating the operation unit 51, the elastic claw 42 can be displaced upward / downward. With the elastic claws 42 positioned below,
The state in which the toner recovery tank 15 is mounted on the toner recovery tank mounting portion 16 can be maintained.

Next, a method of mounting the toner recovery tank 15 to the toner recovery tank mounting portion 16 will be described. First, the elastic claw 42 is displaced upward by the operation of the operation section 51 to position the toner collection tank 15 between the toner collection tank mounting section 16 and other parts, and then the arrow D shown in FIGS. Slide in the direction of. Then, one side surface of the toner collection tank 15 is engaged with the protrusion 40.
When the toner collection tank 15 is further slid, the shutter 38 slides in the direction of arrow D in conjunction with the slide of the toner collection tank 15. When the toner collection tank 15 is slid by a predetermined amount, as shown in FIG. 7, the attachment of the toner collection tank 15 to the image forming unit 7 is achieved, and the elastic claws 42 are displaced downward. When the toner collection tank 15 is mounted, the opening 27 is opened, and the opening 27 and the toner collection tank 15 are opened.
Overlaps with the opening 36.

FIG. 8 is a sectional view of an essential part taken along section line AA in FIG. In FIG. 8, the transport spiral 24 is omitted. The toner conveying path 23 is inclined downward toward the end in the direction of arrow E shown in FIG. For this reason, the toner discharged from the cleaning device 6 can be favorably conveyed to the toner collection tank 15 or the developing device 5.

The toner recovery tank 15 shown in FIG.
In the state where is not mounted, since the opening 27 is closed, all the toner discharged from the cleaning device 6 and transported through the toner transport path 23 is transported to the developing device 5 without being transported to the toner collection tank 15. Also, the toner collection tank 1
5 in the toner collection tank mounting section 16
Since the opening 27 is opened and the opening 27 overlaps the opening 36, the toner discharged from the cleaning device 6 and conveyed through the toner conveying path 23 is conveyed to the toner collecting tank 15, and the toner is collected in the toner collecting tank 15. Can be

With this configuration, the toner collected from the cleaning device 6 is collected in the toner collection tank 15, collected and discarded with a simple configuration by mounting / dismounting the toner collection tank 15, and a cleaning device. It is possible to provide an image forming apparatus that can select both a recycling method in which toner discharged from the printer 6 is transported to the developing device 5 and reused for image formation.

In addition, various design changes can be made within the scope of the matters described in the claims.

[Brief description of the drawings]

FIG. 1 is a schematic longitudinal sectional view for explaining an internal structure of an image forming apparatus according to the present invention.

FIG. 2 is a perspective view illustrating a configuration of an image forming unit.

FIG. 3 is a cross-sectional view of a main part around the image forming unit in a state where the main body is mounted in a housing, as viewed from above.

FIG. 4 is a perspective view of a toner collection tank.

FIG. 5 is a bottom view of the image forming unit for explaining a toner collection tank mounting portion.

FIG. 6 is a diagram illustrating a state in which a toner collection tank is mounted on a toner recovery tank mounting portion.

FIG. 7 is a diagram illustrating a state after the toner collection tank is mounted on the toner recovery tank mounting section.

FIG. 8 is a cross-sectional view of a main part taken along a cutting line AA in FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image forming apparatus 3 Photoreceptor drum 5 Developing device 6 Cleaning device 16 Toner collection tank mounting part 23 Toner conveying path 24 Conveying spiral 25 Rotating shaft 26 Spiral blade 27 Opening

Claims (3)

[Claims] 1. An image forming apparatus for recording an image on a sheet, comprising: a photoreceptor having an electrostatic latent image formed on a surface thereof; and an image forming apparatus for developing the electrostatic latent image on the photoreceptor surface into a toner image. A developing device, a cleaning device for removing residual toner on the surface of the photoreceptor, a toner conveying path communicating the cleaning device and the developing device, an opening formed in the middle of the toner conveying path, and an opening. A toner collection tank mounting section for mounting a toner recovery tank for recovering the toner removed by the cleaning device through the opening; and a state in which the toner recovery tank is mounted on the toner recovery tank mounting section. And an opening opening / closing mechanism that closes the opening when the toner collection tank is not attached to the toner collection tank. 2. The toner conveying path has a rotating shaft extending in the same direction as the toner conveying path and a spiral spiral blade projecting from the rotating shaft. 2. The image forming apparatus according to claim 1, further comprising a toner conveying unit that conveys the toner discharged from the cleaning device to the developing device. 3. The toner conveying path is inclined downward toward the developing device, and the toner collecting tank is mountable below the opening. The image forming apparatus as described in the above.