JP7392504B2 - Image forming device - Google Patents

Description

The present invention relates to an image forming apparatus that includes a rotary bottle that stores waste developer.

Generally, an electrophotographic image forming apparatus includes a rotary bottle that stores powdered waste developer collected from a printing apparatus that forms an image on a sheet. The bottle is a container having an opening formed at one end in the longitudinal direction. Note that the bottle may be referred to as a waste toner bottle, for example.

The bottle has a helical convex portion that protrudes spirally along the longitudinal direction on the inner surface. The bottle is arranged with the longitudinal direction facing sideways, and is driven to rotate. The rotating bottle accommodates the waste developer conveyed to the opening and conveys the waste developer to the back of the bottle.

The image forming apparatus further includes a developer sensor that detects the amount of waste developer in the bottle. When the developer sensor detects that the amount of waste developer in the bottle has reached an upper limit amount, printing processing by the printing device is prohibited.

For example, it is known that the image forming apparatus includes a plurality of capacitance sensors that detect the amount of waste developer at each of a plurality of locations within the bottle (for example, see Patent Document 1).

Japanese Patent Application Publication No. 2018-66789

By the way, the bottle has a hollow small diameter part that occupies a part of the range from the opening, and a hollow large diameter part that is thicker than the small diameter part. The small diameter portion and the large diameter portion are continuous with each other via a step portion.

As the bottle rotates, the waste developer flows from the opening into the large diameter portion via the small diameter portion.

In order for the waste developer to smoothly flow into the large diameter part of the bottle, it is necessary to prevent the waste developer from staying in the small diameter part of the bottle. Further, it is desirable to be able to detect that the amount of waste developer in the bottle has reached the upper limit using as few sensors as possible.

SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus that prevents waste developer from remaining in a small diameter portion of a bottle and can detect when the amount of waste developer in the bottle reaches an upper limit using as few sensors as possible. It is in.

An image forming apparatus according to one aspect of the present invention includes a printing device, a bottle, a drive device, a developer sensor, and a control device. The printing device executes a printing process to form a toner image on a sheet, and discharges powdered waste developer. The bottle is a container having an opening formed at a first end in the longitudinal direction, and is arranged with the longitudinal direction facing sideways and is rotationally driven to collect the waste transported from the printing device to the opening. The developer is accommodated inside and the waste developer inside is conveyed to the second end side in the longitudinal direction. The drive device rotates the bottle. The developer sensor detects the amount of waste developer in the bottle. The control device controls the drive device. The bottle has a hollow small diameter section and a hollow large diameter section. The small diameter portion occupies a range from the first end in the longitudinal direction to a stepped portion formed at a position near the first end. The large diameter portion is formed to extend from the stepped portion toward the second end in the longitudinal direction, and is thicker than the small diameter portion. The developer sensor includes a first developer sensor that detects the amount of the waste developer present in the small diameter portion, and a second developer sensor that detects the amount of the waste developer that exists in the large diameter portion. ,including. In a first case where the first developer sensor and the second developer sensor each detect the waste developer exceeding a predetermined upper limit amount, the control device controls the print processing by the printing device. and in another second case, when operating the drive device in response to establishment of a predetermined operating condition, the rotational speed of the bottle is controlled at least in accordance with the amount detected by the first developer sensor. control.

According to the present invention, it is an object of the present invention to provide an image forming apparatus that can prevent waste developer from staying in a small diameter portion of a bottle and can detect that the amount of waste developer in the bottle has reached an upper limit amount using as few sensors as possible. becomes possible.

FIG. 1 is a configuration diagram of an image forming apparatus according to an embodiment. FIG. 2 is a configuration diagram of a bottle and its surroundings in the image forming apparatus according to the embodiment. FIG. 3 is a block diagram showing the configuration of control-related equipment in the image forming apparatus according to the embodiment. FIG. 4 is a diagram illustrating an example of the relationship between the amount detected by the developer sensor and the bottle driving speed in the image forming apparatus according to the embodiment.

Embodiments of the present invention will be described below with reference to the drawings. Note that the following embodiments are examples of embodying the present invention, and do not limit the technical scope of the present invention.

[Configuration of image forming apparatus 10]
The image forming apparatus 10 according to the embodiment is an apparatus that forms an image on a sheet using an electrophotographic method. The sheet is a sheet-like image forming medium such as paper or a resin film.

The image forming apparatus 10 includes a paper feeding section 30, a sheet conveying device 3, a printing device 4, one or more toner containers 400, a bottle 5, and a waste developer collecting device 6, which are arranged in the main body 1.

The paper feed section 30 is a device that accommodates a plurality of sheets and sends out the accommodated sheets one by one to the sheet conveyance path 300. The sheet conveyance device 3 conveys the sheet along a sheet conveyance path 300.

The printing device 4 executes a printing process of forming a toner image using an electrophotographic method on the sheet fed from the paper feeding section 30 through the sheet conveying device 3.

The printing device 4 includes a laser scanning unit 40, one or more image forming devices 4x, a transfer device 44, and a fixing device 46.

In the example shown in FIG. 1, the printing device 4 is a tandem type color image printing device. Therefore, the printing device 4 includes four toner containers 400 corresponding to four colors of toner and four image forming devices 4x. Each of the image forming devices 4x includes a drum-shaped photoreceptor 41, a charging device 42, a developing device 43, and a drum cleaning device 45.

In each of the image forming devices 4x, the photoreceptor 41 rotates, and the charging device 42 charges the outer peripheral surface of the photoreceptor 41. Further, in each of the image forming devices 4x, a developing device 43 develops the electrostatic latent image formed on the outer peripheral surface of the photoreceptor 41 by the laser scanning unit 40 into a toner image. The photoreceptor 41 is an example of an image carrier.

Furthermore, the transfer device 44 includes an intermediate transfer belt 440, four primary transfer devices 441, a secondary transfer device 442, and a belt cleaning device 443.

The intermediate transfer belt 440 rotates while contacting the four photoreceptors 41, and the four primary transfer devices 441 transfer the toner images from the four photoreceptors 41 to the intermediate transfer belt 440.

The secondary transfer device 442 transfers the toner image on the intermediate transfer belt 440 to the sheet being conveyed through the sheet conveyance path 300. Belt cleaning device 443 removes waste toner from intermediate transfer belt 440 . Further, in each of the image forming devices 4x, a drum cleaning device 45 removes waste toner remaining on the outer peripheral surface of the photoreceptor 41.

The fixing device 46 fixes the toner image on the sheet by heating and pressing the toner image on the sheet. The sheet conveyance device 3 discharges the sheet on which the image is formed from the sheet conveyance path 300.

Each toner container 400 supplies toner 9 to a corresponding developing device 43 in the printing device 4 .

In the printing device 4, the developing device 43 discharges granular waste developer 90 containing waste toner that has remained for a long period of time. Further, the drum cleaning device 45 and the belt cleaning device 443 discharge waste developer 90, which is a removed material. The waste developer collecting device 6 collects the waste developer 90 discharged from the printing device 4 into the bottle 5 .

Furthermore, when the developing device 43 performs development using a two-component developer containing toner 9 and carrier, the waste developer also includes waste carrier that has remained in the developing device 43 for a long period of time. Furthermore, the waste developer and the material removed by the drum cleaning device 45 and the belt cleaning device 443 may include the waste carrier.

As shown in FIG. 2, the bottle 5 is a container in which an opening 50 is formed at a first end 51 in the longitudinal direction. For example, the bottle 5 is a container made of synthetic resin. The bottle 5 has a cylindrical outer peripheral surface 53. A straight line along the longitudinal direction of the bottle 5 is the center line L0 of the outer peripheral surface 53.

The bottle 5 has a helical convex portion 54 that protrudes spirally along the longitudinal direction on the inner surface. Note that the spiral convex portion 54 is a spiral concave portion when viewed from the outside of the bottle 5.

The bottle 5 is arranged with the longitudinal direction facing sideways, and is driven to rotate. Thereby, the bottle 5 accommodates therein the waste developer 90 conveyed from the developing device 43 and the belt cleaning device 443 to the opening 50, and conveys the waste developer 90 inside toward the second end 52 side in the longitudinal direction. do.

Furthermore, the image forming apparatus 10 includes a control device 8, an operating device 8a, and a display device 8b. The operating device 8a is a touch panel, operating buttons, or the like that accepts human operations. The display device 8b is a liquid crystal panel unit or the like that displays information.

As shown in FIG. 3, the control device 8 includes a CPU (Central Processing Unit) 81, a RAM (Random Access Memory) 82, a secondary storage device 83, an image data processing device 84, and the like.

The CPU 81 is an example of a processor that controls electrical equipment in the image forming apparatus 10 and performs various data processing by executing programs stored in the secondary storage device 83 or the like.

It is also conceivable that another processor such as a DSP (Digital Signal Processor) executes various controls and data processing instead of the CPU 81.

The RAM 82 is a storage device that temporarily stores the program executed by the CPU 81 and data output and referenced during the process of the CPU 81 executing the program.

Secondary storage 83 is a computer readable non-volatile data storage. The secondary storage device 83 can store the program and various data. For example, one or a combination of a hard disk drive and an SSD (Solid State Drive) is employed as the secondary storage device 83.

The image data processing device 84 executes image processing such as processing or conversion processing on the image data used in the print processing. For example, the image data processing device 84 executes processing such as converting print job data into raster data for printing.

For example, the image data processing device 84 is realized by one or both of a processor such as a DSP and an integrated circuit such as an ASIC (Application Specific Integrated Circuit).

[Waste developer recovery device 6]

As shown in FIGS. 1 and 2, the waste developer recovery device 6 includes a waste developer transport mechanism 60, a bottle support section 61, a carry-in relay section 62, and a bottle drive mechanism 63.

The bottle support portion 61 supports the bottle 5 containing the waste developer 90. The bottle 5 is placed on the bottle support part 61 with the longitudinal direction facing sideways. The waste developer transport mechanism 60 transports the waste developer 90 discharged from the developing device 43 and the belt cleaning device 443 to the carry-in relay section 62 .

The carry-in relay section 62 is a member that forms a guide duct 62a. The carry-in relay section 62 guides the waste developer 90 transported into the guide duct 62 a by the waste developer transport mechanism 60 to the opening 50 of the bottle 5 supported by the bottle support section 61 .

The bottle drive mechanism 63 is connected to the first end 51 of the bottle 5 supported by the bottle support section 61 and drives the bottle 5 to rotate. The motor 6a, which is the drive source of the bottle drive mechanism 63, is controlled by the control device 8 (see FIG. 2).

In this embodiment, the motor 6a and the bottle drive mechanism 63 are an example of a drive device that rotationally drives the bottle 5.

The bottle drive mechanism 63 transmits the rotational force of the motor 6a to the first end 51 of the bottle 5. The bottle 5 receives power from the bottle drive mechanism 63 and rotates around the center line L0 in a predetermined rotation direction.

By rotating the bottle 5 in the predetermined rotation direction, the waste developer 90 in the bottle 5 is conveyed toward the second end 52 and is leveled along the longitudinal direction of the bottle 5. By rotating the bottle 5, the waste developer 90 is prevented from staying in the bottle 5 toward the opening 50 side.

The bottle 5 is removably attached to the bottle support section 61 and the bottle drive mechanism 63. When the amount of waste developer 90 in the bottle 5 reaches the upper limit amount, the bottle 5 is replaced.

By the way, the bottle 5 has a hollow small diameter part 5a that occupies a part of the range from the opening 50, and a hollow large diameter part 5b that is thicker than the small diameter part 5a. The small diameter portion 5a and the large diameter portion 5b are connected to each other via a stepped portion 5c.

The small diameter portion 5a occupies a range from the first end 51 of the bottle 5 in the longitudinal direction to the stepped portion 5c. The stepped portion 5c is formed at a position closer to the first end 51 in the longitudinal direction of the bottle 5. The large diameter portion 5b is formed to extend from the stepped portion 5c toward the second end 52 in the longitudinal direction.

As the bottle 5 rotates, the waste developer 90 flows from the opening 50 into the large diameter portion 5b via the small diameter portion 5a.

In order for the waste developer 90 to smoothly flow into the large diameter portion 5b of the bottle 5, it is necessary to prevent the waste developer 90 from remaining in the small diameter portion 5a of the bottle 5. Further, it is desirable to be able to detect that the amount of waste developer 90 in the bottle 5 has reached the upper limit using as few sensors as possible.

Hereinafter, the image forming apparatus 10 will be described to prevent the waste developer 90 from staying in the small diameter portion 5a of the bottle 5 and to detect when the waste developer 90 in the bottle 5 has reached the upper limit amount using as few sensors as possible. Explain the characteristics.

As shown in FIG. 3, the image forming apparatus 10 further includes a humidity sensor 70 and developer sensors 71 and 72. The developer sensors 71 and 72 include a first developer sensor 71 and a second developer sensor 72.

Humidity sensor 70 detects the humidity of the installation environment of image forming apparatus 10 . The first developer sensor 71 and the second developer sensor 72 detect the amount of waste developer 90 in the bottle 5 .

In this embodiment, the first developer sensor 71 and the second developer sensor 72 are each capacitance sensors.

The first developer sensor 71 is arranged to face the small diameter portion 5a of the bottle 5. Thereby, the first developer sensor 71 detects the amount of waste developer 90 present in the small diameter portion 5a.

On the other hand, the second developer sensor 72 is disposed facing the large diameter portion 5b of the bottle 5. Thereby, the second developer sensor 72 detects the amount of waste developer 90 present within the large diameter portion 5b.

In the example shown in FIG. 2, the second developer sensor 72 is arranged to face a portion of the large diameter portion 5b of the bottle 5 near the second end 52. In the example shown in FIG. In this case, the second developer sensor 72 detects the amount of waste developer 90 present in a portion of the large diameter portion 5b closer to the second end 52. Note that the second developer sensor 72 is disposed opposite to a portion of the large diameter portion 5b of the bottle 5 near the stepped portion 5c, and detects the amount of waste developer 90 present in the opposing portion. can also be considered.

The CPU 81 of the control device 8 operates the bottle drive mechanism 63 by operating the motor 6a when predetermined operating conditions are satisfied.

Specifically, the operating condition is a condition that is satisfied from the start to the end of the printing process. That is, the operating conditions of the bottle drive mechanism 63 in this embodiment are conditions under which the printing device 4 executes the printing process. For example, the operating condition is satisfied from when a print job that is a request for execution of the print process is generated until the print process corresponding to the print job is completed.

However, in the first case where the first developer sensor 71 and the second developer sensor 72 detect that the bottle 5 is full, the CPU 81 prohibits the printing device 4 from executing the printing process. In the first case, the CPU 81 does not cause the printing device 4 to execute the printing process even if the operating condition is satisfied.

The full state means that the first developer sensor 71 detects waste developer 90 exceeding a predetermined first upper limit amount, and the second developer sensor 72 detects waste developer 90 exceeding a predetermined second upper limit amount. This is a state in which the developer 90 is detected.

When the first developer sensor 71 and the second developer sensor 72 detect the full state, the CPU 81 notifies via the display device 8b that the bottle 5 needs to be replaced.

On the other hand, in the second case where the first developer sensor 71 and the second developer sensor 72 do not detect the full state, the CPU 81 operates the motor 6a when the operating condition is satisfied. The bottle drive mechanism 63 is activated.

Hereinafter, the control of the rotational speed of the bottle 5 when the CPU 81 operates the motor 6a in accordance with the establishment of the operating condition in the second case where the full state is not detected will be referred to as steady bottle drive control. . The CPU 81 controls the rotational speed of the bottle 5 by controlling the amount of power supplied to the motor 6a.

Further, the amount detected by the first developer sensor 71 is referred to as a first detected amount Q1, and the amount detected by the second developer sensor 72 is referred to as a second detected amount Q2 (see FIGS. 3 and 4).

In the steady bottle drive control, the CPU 81 controls the rotational speed of the bottle 5 according to at least the amount detected by the first developer sensor 71.

FIG. 4 shows an example of the relationship between the amounts detected by the developer sensors 71 and 72 and the bottle rotation speed V0 in the steady bottle drive control.

The broken line graph in FIG. 4 shows an example of the relationship between the second detected amount Q2 and the bottle rotation speed V0 when the first detected amount Q1 exceeds a predetermined first reference amount Q10.

Moreover, the solid line graph in FIG. 4 shows an example of the relationship between the second detected amount Q2 and the bottle rotation speed V0 when the first detected amount Q1 is less than or equal to the first reference amount Q10. Note that the first reference amount Q10 is an amount smaller than the first upper limit amount.

As shown in FIG. 4, in the steady bottle drive control, the CPU 81 sets the bottle rotation speed V0 to the first speed V1 when the first detected amount Q1 exceeds the first reference amount Q10, and otherwise sets the bottle rotation speed V0 to the first speed V1. Then, the bottle rotational speed V0 is set to a second speed V2 or a third speed V3, which are lower than the first speed V1, respectively.

That is, in the steady bottle drive control, the CPU 81 rotates the bottle 5 at a lower speed when the first detected amount Q1 is small than when the first detected amount Q1 is large. This prevents the waste developer 90 from remaining in the small diameter portion 5a of the bottle 5.

In the image forming apparatus 10, it is possible to detect that the amount of waste developer 90 in the bottle 5 has reached the upper limit using only the two developer sensors 71 and 72.

Further, in the example shown in FIG. 4, the CPU 81 determines that when the first detected amount Q1 does not exceed the first reference amount Q10, and the second detected amount Q2 exceeds the predetermined second reference amount Q20, The bottle rotation speed V0 is set to a second speed V2 when the second detection amount Q2 does not exceed the second reference amount Q20, and the bottle rotation speed V0 is set to a third speed V3 that is slower than the second speed V2. .

That is, when the first detected amount Q1 is less than the first reference amount Q10, the CPU 81 rotates the bottle 5 at a lower speed than when the second detected amount Q2 is small and when the second detected amount Q2 is large. In this case, in the steady bottle drive control, the CPU 81 selects the bottle rotational speed V0 from three predetermined speeds according to the combination of the first detected amount Q1 and the second detected amount Q2.

In addition, in the steady bottle drive control, the CPU 81 may select the bottle rotational speed V0 from four or more predetermined speeds according to the combination of the first detected amount Q1 and the second detected amount Q2.

By the steady bottle drive control as described above, the power consumption of the motor 6a can be suppressed when the amount of waste developer 90 in the large diameter portion 5b is relatively small and there is no problem even if the bottle 5 is rotated at a low speed. .

Further, in the steady bottle drive control, it is also considered that the CPU 81 corrects the bottle rotation speed V0, which is set according to the combination of the first detected amount Q1 and the second detected amount Q2, according to the humidity detected by the humidity sensor 70. It will be done.

For example, when the humidity detected by the humidity sensor 70 exceeds a predetermined reference humidity, the CPU 81 increases the bottle rotation speed V0 by one step, which is set according to the combination of the first detection amount Q1 and the second detection amount Q2. It is conceivable to correct the speed.

In this embodiment, the speed that is one step higher than the third speed V3 is the second speed V2, and the speed that is one step faster than the second speed V2 is the first speed V1.

Generally, when the humidity is high, the waste developer 90 tends to stay in the small diameter portion 5a. Therefore, when the humidity is high, the CPU 81 corrects the bottle rotational speed V0 to be increased, thereby more reliably preventing the waste developer 90 from accumulating in the small diameter portion 5a of the bottle 5.

1: Main body 3: Sheet conveying device 4: Printing device 4x: Image forming device 5: Bottle 5a: Small diameter section 5b: Large diameter section 5c: Step section 6: Waste developer collection device 6a: Motor 8: Control device 8a: Operation Device 8b: Display device 9: Toner 10: Image forming device 30: Paper feed section 40: Laser scanning unit 41: Photoreceptor 42: Charging device 43: Developing device 44: Transfer device 45: Drum cleaning device 46: Fixing device 50: Bottle opening 51 : First end 52 of the bottle : Second end 53 of the bottle : Outer peripheral surface 54 of the bottle : Spiral convex part 60 : Waste developer transport mechanism 61 : Bottle support part 62 : Carrying in relay part 62a : Guide duct 63 : Bottle drive mechanism 70 : Humidity sensor 71 : First developer sensor 72 : Second developer sensor 81 : CPU
82: RAM
83: Secondary storage device 84: Image data processing device 90: Waste developer 300: Sheet conveyance path 400: Toner container 440: Intermediate transfer belt 441: Primary transfer device 442: Secondary transfer device 443: Belt cleaning device

Claims (5)

a printing device that executes a printing process to form a toner image on a sheet and discharges powdered waste developer;
The container has an opening formed at a first end in the longitudinal direction, and is arranged with the longitudinal direction facing sideways, and is rotated so that the waste developer transported from the printing device to the opening is stored inside the container. a bottle that accommodates the waste developer inside and conveys the waste developer therein to the second end side in the longitudinal direction;
a drive device that rotationally drives the bottle;
a developer sensor that detects the amount of the waste developer in the bottle;
An image forming apparatus comprising: a control device that controls the printing device and the drive device;
The bottle is
a hollow small diameter portion that occupies a range from the first end in the longitudinal direction to a stepped portion formed at a position near the first end;
a hollow large-diameter portion extending from the step portion toward the second end in the longitudinal direction and thicker than the small-diameter portion;
The developer sensor is
a first developer sensor that detects the amount of the waste developer present in the small diameter portion;
a second developer sensor that detects the amount of the waste developer present in the large diameter portion,
In a first case where the first developer sensor and the second developer sensor each detect the waste developer exceeding a predetermined upper limit amount, the control device controls the print processing by the printing device. and in another second case, when operating the drive device in response to establishment of a predetermined operating condition, the rotational speed of the bottle is controlled at least in accordance with the amount detected by the first developer sensor. An image forming device that controls. In the second case, when operating the drive device in response to establishment of the operating condition, the control device controls a combination of the detection amount of the first developer sensor and the detection amount of the second developer sensor. The image forming apparatus according to claim 1, wherein the rotational speed of the bottle is selected from three or more predetermined speeds depending on the rotational speed of the bottle. further comprising a humidity sensor that detects humidity in an installation environment of the image forming apparatus,
When the control device operates the drive device in response to establishment of the operating condition, the control device is configured to set the control device according to a combination of the detection amount of the first developer sensor and the detection amount of the first developer sensor. The image forming apparatus according to claim 2, wherein the rotational speed of the bottle is corrected according to humidity detected by the humidity sensor. The image forming apparatus according to any one of claims 1 to 3, wherein the operating condition is a condition under which the printing apparatus executes the printing process. The image forming apparatus according to any one of claims 1 to 4, wherein the first developer sensor and the second developer sensor are each capacitance sensors.

Images