JPH1184970A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To discharge toner in a toner carrying path in a state where the driving of a cleaning device is stopped and to prevent the solidification of toner so as to prevent the residual toner from being faultily carried by respectively driving the cleaning device and a toner recovering device by separate driving sources. SOLUTION: A magnet roller 13 and a doctor roller 14 in the cleaning device B are driven by the driving force of a cleaning motor 19. Meanwhile, the toner carrying screw 16 of the toner recovering device C is driven by the driving force of a recovering motor 20. The respective motors 19 and 20 can be driven independently. After image forming operation is finished, only the motor 20 is driven in a state where the motor 19 is stopped. Since only the motor 20 driving the device C is driven, the residual toner in the toner carrying path 15 is discharged to a recovery container 17 without rotating the roller 13 in the midst of stopping the image forming operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus for forming an image using toner, such as a copying machine or a printer, and more particularly to a method for collecting waste toner without coagulation in a transport path. The present invention relates to a possible image forming apparatus.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus, as shown in FIG. 5, after a toner image formed on a photosensitive drum 50 as an image carrier is transferred to a transfer material, an obstacle to the next image formation is obtained. Before the next image forming process is started, the toner remaining on the image carrier is removed using the cleaning device 51 before the next image forming process is started. FIG. 5A shows the overall configuration of the image forming apparatus, and FIG. 5B shows the configuration of the cleaning device and the toner collecting device.

[0003] A cleaning device 51 scrapes residual toner on the surface of the photosensitive drum 50 with a cleaning blade 52 pressed against the surface of the photosensitive drum 50, rotates a magnet roller 53 and a doctor roller 54, and conveys the toner to a conveying screw.
55, and then the toner collection device shown in FIG.
By rotating the conveying screw 55, the residual toner is collected in the toner collecting container 58 through the toner conveying path 57.

At this time, since the tip of the cleaning blade 52 receives a force in the rotating direction of the photosensitive drum 50, the cleaning blade 52 is easily deformed such as being turned up. To prevent this, the magnet roller 53 is rotated to apply the toner accumulated in the toner accumulation unit 59 onto the surface of the photosensitive drum 50 through the surface of the magnet roller 53, and the toner is used as a lubricant for the cleaning blade 52. The cleaning blade 52 is configured to scrape off the residual toner at the same time.

[0005]

The cleaning operation as described above is normally performed during the image forming operation, and the driving source is stopped when the image forming operation is stopped. Therefore, when the image forming operation is performed before the stop, the residual toner to be conveyed to the toner collecting container 58 in the toner collecting device 56 is stopped while remaining in the toner conveying path 57 while being conveyed. doing.

If the stopped state of the image forming apparatus continues for a long time, the toner in the transport path 57 starts to solidify with the lapse of time, and finally, the toner adheres to the toner transport path 57 and the transport screw 55, causing a toner transport failure. May cause some trouble.

Further, a fixing device 60 for fixing a transferred image includes:
Generally, the residual heat is applied even while the image forming operation is stopped, and when the image forming operation is restarted, the time required to reach the fixing temperature is shortened so that the image forming can be started immediately. The toner collecting device 56 is often arranged near the fixing device 60 on the arrangement inside the image forming apparatus main body, and is easily affected by the heat from the fixing device 60 even during the stop of the image forming operation. The inside of the toner collecting device 56 is under a condition in which the toner is easily solidified.

Further, in recent years, the toner tends to be reduced in particle size in order to improve the image quality of the formed image, so that the coagulation due to the elapse of the stop time and the rise in temperature is more likely to occur. In order to solve this, all the residual toner in the toner conveyance path 57 during the stop of the image forming operation is discharged into the toner collection container 58.

However, since the driving of the cleaning device 51 and the driving of the toner collecting device 56 are performed from the same driving source 61 via the gear train 62, if the transporting device is driven while the image forming operation is stopped, the cleaning is performed. The magnet roller 53 in the device 51 also rotates at the same time.

On the other hand, if the toner collecting device 56 is driven while the image forming operation is stopped, the magnet roller 53 in the cleaning device 51 also rotates. And
If the magnet roller 53 rotates while the image forming operation is stopped, the photosensitive drum 50 is stopped, so that the toner between the magnet roller 53 and the surface of the photosensitive drum 50 is removed.
The photoreceptor drum 50
The surface is easily damaged.

Further, since the toner on the magnet roller 53 is scraped off on the surface of the photosensitive drum 50, the toner drops on the transfer material conveying belt 63, and when the image forming operation is performed again, the belt 63 There is a possibility that the transfer material conveyed by the cleaning may become dirty.

Further, since the toner in the toner storage unit 59 is consumed, when the image forming operation is performed again, the toner as the lubricant cannot be sufficiently applied on the surface of the photosensitive drum 50, and The cleaning blade 52 may be deformed such as turning over the blade.

The present invention has been made to solve the above problems,
An object of the present invention is to provide an image forming apparatus capable of preventing toner from coagulating in a conveyance path of a toner collecting device.

[0014]

A typical configuration according to the present invention for achieving the above object is to form a toner image on an image carrier, and transfer the toner image to a recording medium to form an image. A cleaning device that removes toner remaining on the image carrier after the image transfer, and a toner collection device that collects the toner removed by the cleaning device into a collection container via a toner conveyance path. , And the cleaning device and the toner collecting device are configured to be driven by different driving sources.

In the above configuration, by driving the toner collecting device after the image forming operation is stopped, the toner in the toner conveying path can be discharged to the collecting container while the driving of the cleaning device is stopped. At this time, since the driving of the cleaning device is stopped, there is no possibility of damaging the surface of the image carrier.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a preferred embodiment according to the image forming apparatus of the present invention will be described with reference to the drawings.

[First Embodiment] A first embodiment will be described with reference to FIGS. 1 and 2. FIG. FIG. 1 is an explanatory view of the overall configuration of the image forming apparatus, and FIG. 2 is a schematic explanatory view of the configuration of a cleaning device and a toner collecting device.

Here, as an order of explanation, first, the overall configuration of the image forming apparatus will be described, and then the configurations of the cleaning device and the toner collecting device will be described.

<< Overall Configuration of Image Forming Apparatus >> As shown in FIG. 1, this image forming apparatus A irradiates a light image based on image information from an optical system 1 to a toner drum on an image carrier. Form an image. Then, in synchronization with the formation of the toner image, the transfer material 2 is transported from the cassette 3a by a transporting unit 3 including a pickup roller 3b and a pair of registration rollers 3c, and is formed on the photosensitive drum in an image forming unit described later. The applied toner image is transferred to the transfer material 2 by applying a voltage to a transfer roller 4 as a transfer unit.

Further, the transfer material 2 after image transfer is transferred to a guide plate 3d.
And is conveyed to the fixing means 5. This fixing means 5
Is composed of a fixing roller 5a having a built-in heater and a driving roller 5b, and applies heat and pressure to the passing transfer material 2 to fix the transferred toner image. The transfer material 2 is conveyed by a pair of discharge rollers 3e, and is discharged to a discharge section 6 through a reverse conveyance path 3f.

On the other hand, the image forming section rotates a photosensitive drum 7 having a photosensitive layer and uniformly charges the surface thereof by applying a voltage to a charging roller 8 serving as a charging means.
The latent image is formed by exposing the light image from the photosensitive drum 7 to the photosensitive drum 7 via the exposure unit 9, and the latent image is developed by the developing unit 10.

The developing means 10 sends out the toner T1 in the toner hopper 10a by a toner sending member (not shown), rotates a developing roller 10b containing a fixed magnet, and applies a triboelectric charge by a developing blade 10c. The formed toner layer is formed on the surface of the developing roller 10b, and the toner is transferred to the photosensitive drum 7 in accordance with the latent image, thereby forming a toner image and visualizing the toner image. Then, after a voltage having a polarity opposite to that of the toner image is applied to the transfer roller 4 to transfer the toner image to the transfer material 2, the toner remaining on the photosensitive drum 7 is removed by a cleaning device B to be described later. Collect by C.

{Cleaning device and toner collecting device}
The configuration of the cleaning device B is as shown in FIG.
A cleaning blade 11, a magnet roller 13, and a doctor roller 14 are incorporated in a cleaning container 11. On the other hand, as shown in FIG. 2, the toner collecting device C is provided with a transport screw 16 in a pipe forming a toner transport path 15 having one end communicating with the cleaning device B, and the other end of the transport path 15 It communicates with the toner collecting container 17.

The residual toner T 2 on the surface of the photosensitive drum 7 is scraped by a cleaning blade 12 pressed against the surface of the photosensitive drum 7, and the magnet roller 13 and the doctor roller 14 are rotated to convey the toner to the conveying screw 16. Then, the transport screw 16 of the toner recovery device C is rotated,
The toner remaining in the toner collecting container 17 is collected through the toner conveying path 15.

At this time, since the tip of the cleaning blade 12 receives a force in the rotation direction of the photosensitive drum 7, deformation such as turning up of the cleaning blade 12 easily occurs. To prevent this, as in the conventional case, the magnet roller 13 is rotated to apply the toner accumulated in the toner accumulating section 18 (see FIG. 1) onto the surface of the photosensitive drum 7 through the magnet roller 13 and the toner Is used as a lubricant for the cleaning blade 12, and the cleaning blade 12 scrapes off the residual toner at the same time.

In this embodiment, the driving of the magnet roller 13 and the doctor roller 14 in the cleaning device B is performed by transmitting the driving force of the cleaning motor 19 through a gear train 19a. On the other hand, the driving of the toner conveying screw 16 of the toner collecting device C is configured to be driven by transmitting the driving force of the collecting motor 20 via a gear train 20a, and the respective motors 19 and 20 are independently driven. It is possible.

In this embodiment, after the image forming operation is completed by the drive control means, the cleaning motor 19 is stopped and only the collection motor 20 is driven. As a result, since all the residual toner in the toner transport path 15 can be discharged to the collection container 17, it is possible to prevent the coagulation of the toner due to the elapse of the residence time and the influence of the temperature, and to prevent the residual toner transport failure. Can be.

Further, since only the collecting motor 20 for driving the toner collecting device C is driven, the residual toner in the toner conveying path 15 is discharged to the collecting container 17 without rotating the magnet roller 13 during the stop of the image forming operation. It is possible.
As a result, while the image forming operation is
Can prevent damage to the surface of the photosensitive drum 7, contamination of the transfer material, and deformation of the cleaning blade due to rotation of the cleaning drum.

Further, the above-described sequence is performed for a predetermined time after the image forming operation is completed.
It is possible to perform a stable image forming operation for a long period of time.

Second Embodiment Next, another embodiment of the cleaning device B and the toner collecting device C will be described with reference to FIG. 3A is a top view of the cleaning device and the toner collecting device, and FIG. 3B is a side view. Since the entire configuration of the image forming apparatus is the same as that of the above-described first embodiment, description thereof will be omitted here, and members having the same functions as those of the first embodiment will be denoted by the same reference numerals.

In this embodiment, the toner transport path
A temperature / humidity sensor 21 capable of detecting temperature and humidity is provided in 15, and the recovery motor 20 is driven in accordance with a signal from the sensor 21.

When the temperature and humidity in the toner transport path 15 approach the condition for solidifying the toner, the temperature and humidity are detected by the temperature and humidity sensor.
The detection is made by 21 and the drive control means drives only the collection motor 20 of the toner collection device C to rotate the toner conveying screw 16. This allows the residual toner in the toner transport path 15 to be discharged to the collection container 17 when the temperature and humidity approach the temperature at which toner coagulation starts. For this reason,
It is possible to prevent toner from sticking to the toner transport path 15 and the transport screw 16 due to the influence of temperature and humidity, and to prevent poor transport of residual toner.

[Third Embodiment] Next, another embodiment of the cleaning device B and the toner collecting device C will be described. FIGS. 4A and 4B are schematic diagrams illustrating the configuration of a cleaning device and a toner collecting device according to the third embodiment. FIG. 4A is a top view and FIG. 4B is a side view. Also in this embodiment, since the overall configuration of the image forming apparatus is the same as that of the above-described first embodiment, the description is omitted here, and members having the same functions as those of the first embodiment are denoted by the same reference numerals. Is attached.

In this embodiment, the toner transport path
A toner sensor 22 capable of detecting the amount of toner is provided in the sensor 15, the sensor 22 detects the amount of toner in the transport path 15, and drives the collection motor 20 in accordance with a signal from the sensor 22. It is configured.

After the image forming operation is stopped, only the collecting motor 20 of the toner collecting device C is driven for a predetermined time, and the toner conveying screw 16 is rotated. Alternatively, as shown in the second embodiment, only the recovery motor 20 is driven by the signal from the temperature and humidity sensor 21 to rotate the toner conveying screw 16. At this time, the toner sensor 22 is
The control means stops the collection motor 20 and stops the toner conveying screw 16 when the remaining toner amount becomes equal to or less than a predetermined amount.

Thus, the amount of toner in the toner transport path 15 is detected, and the collection motor 20 can be driven until the toner in the toner transport path 15 is completely discharged. Therefore, it is possible to more effectively prevent the solidification of the toner due to the elapse of the residence time, the influence of the temperature, and the like, and to prevent the conveyance failure of the residual toner.

[0037]

The present invention is constructed as described above.
By driving the toner collecting device after the image forming operation is stopped, the toner in the toner conveying path can be discharged to the collecting container while the driving of the cleaning device is stopped. For this reason, solidification of the toner and the like can be prevented, and defective conveyance of the residual toner can be prevented. In addition, when the toner is collected, stopping the driving of the cleaning device can prevent the surface of the image carrier from being damaged.

Further, by driving the recovery of the toner according to the state of temperature and humidity or the amount of toner in the toner conveying path, it is possible to more effectively prevent the solidification of the toner. .

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an overall configuration of an image forming apparatus.

FIGS. 2A and 2B are schematic explanatory diagrams of the configuration of a cleaning device and a toner recovery device, wherein FIG. 2A is a top view and FIG.

FIGS. 3A and 3B are schematic diagrams illustrating the configuration of a cleaning device and a toner collecting device according to a second embodiment, where FIG. 3A is a top view and FIG. 3B is a side view.

FIGS. 4A and 4B are schematic diagrams illustrating the configuration of a cleaning device and a toner collecting device according to a third embodiment, where FIG. 4A is a top view and FIG. 4B is a side view.

FIGS. 5A and 5B show a conventional image forming apparatus, in which FIG. 5A shows the overall configuration, and FIG. 5B is an explanatory diagram of the configuration of a cleaning device and a toner collecting device.

[Explanation of symbols]

 A: Image forming apparatus B: Cleaning device C: Toner collecting device T2: Waste toner 1 ... Optical system 2 ... Transfer material 3 ... Conveying means 3a ... Cassette 3b ... Pickup roller 3c ... Registration roller pair 3d ... Guide plate 3e ... Discharge roller Pair 3f: Reverse transport path 4: Transfer roller 5: Fixing means 5a: Fixing roller 5b: Drive roller 6: Ejector 7: Photoconductor drum 8: Charging roller 9: Exposure unit 10: Developing means 10a: Toner hopper 10b: Development Roller 10c Developing blade 11 Cleaning container 12 Cleaning blade 13 Magnet roller 14 Doctor roller 15 Toner transport path 16 Toner transport screw 17 Toner recovery container 18 Toner storage unit 19 Cleaning motor 19a Gear train 20 … Recovery motor 20a… Gear train 21… Heat and humidity sensor 22… Toner cell Support

Claims (5)

[Claims] 1. An image forming apparatus for forming a toner image on an image carrier and transferring the toner image to a recording medium to form an image, wherein the toner remaining on the image carrier after the image transfer is removed. A cleaning device, and a toner collection device that collects the toner removed by the cleaning device into a collection container via a toner conveyance path, wherein the cleaning device and the toner collection device are respectively driven by different driving sources. An image forming apparatus configured to be driven. 2. The image forming apparatus according to claim 1, wherein the toner collecting device is driven while the image forming operation is stopped. 3. The image forming apparatus according to claim 1, wherein the toner collecting device is driven for a predetermined time after the completion of the image forming operation. 4. The image forming apparatus according to claim 1, wherein the toner collecting device is driven in accordance with a detection result of a temperature and humidity sensor for detecting a temperature and a humidity inside the apparatus main body. 5. The image forming apparatus according to claim 1, wherein the toner recovery device is driven in accordance with a detection result of a toner sensor that detects toner in the toner transport path.