JP5818829B2 - Image forming apparatus - Google Patents

Description

  The embodiment described in this specification relates to a technique for detecting a remaining amount of toner in a toner bottle.

  An image forming apparatus that forms an image on a sheet using toner is known (for example, Patent Document 1). An image forming apparatus includes a photosensitive member that carries an electrostatic latent image on a photosensitive surface, a developing unit that develops the electrostatic latent image on the photosensitive member using toner, and a replaceable toner that supplies toner to the developing unit. With a bottle. The photoreceptor transfers the toner image directly or indirectly to the sheet.

  In the image forming apparatus, the toner in the toner bottle is discharged out of the bottle by driving the auger screw in the bottle. The toner discharged out of the bottle falls freely in the toner conveyance path and reaches the developing device. In the image forming apparatus, the remaining amount of toner in the toner bottle is calculated based on the integrated value of the driving time of the auger screw.

JP 2009-301045 A

  However, the toner supply amount when the auger screw is driven is not always constant. Therefore, a large error may occur in the calculated value of the remaining toner amount calculated based on the integrated value of the driving time of the auger screw.

  This specification aims to provide a technique capable of improving the accuracy of the calculated value of the remaining amount of toner in the toner bottle.

In general, according to the embodiment, the image forming apparatus includes a photoconductor, a developing device, a toner bottle, and a measuring unit. The photoreceptor carries an electrostatic latent image on the photosensitive surface. The developing device develops the electrostatic latent image using toner. The toner bottle supplies toner to the developing device. The measuring unit stores a predetermined amount of toner discharged from the toner bottle, measures the predetermined amount of toner, and discharges the predetermined amount of toner to the developing device. The measurement unit includes a first storage unit that can store a predetermined amount of toner, a sensor that detects whether or not the toner in the first storage unit has reached a predetermined amount, and supply of toner from the toner bottle side to the first storage unit A first shutter that opens and closes the path, and when the sensor detects that the toner in the first container has reached a predetermined amount, the first shutter that closes the supply path from the toner bottle side, and development from within the first container A second shutter that opens and closes a toner supply path to the developer side, and that opens a supply path to the developer side when the sensor detects that the toner in the first storage portion reaches a predetermined amount; .

1 is a functional block diagram of an image forming apparatus according to a first embodiment. FIG. 3 is a schematic diagram illustrating a toner conveyance path and a measurement unit. It is a perspective view which shows the outline of a measurement part. It is a flowchart which shows preparatory operation control of a measurement part. 6 is a flowchart illustrating toner supply processing. It is a perspective view which shows the outline of the measurement part of 2nd Embodiment. FIG. 6 is a schematic diagram illustrating a toner measurement operation by a measurement unit. FIG. 6 is a schematic diagram illustrating a toner measurement operation by a measurement unit. 6 is a flowchart illustrating toner supply processing. It is a schematic front view which shows the modification of the measurement part of 2nd Embodiment.

Hereinafter, embodiments will be described with reference to the drawings.
FIG. 1 is a functional block diagram of the image forming apparatus 1.
The image forming apparatus 1 includes first and second sheet stacking units 11 and 12, a sheet feeding unit 13, a sheet conveying path 14, an image forming unit 2, a fixing device 15, a display unit 16, an operation input unit 17, and a control unit 18 ( A remaining amount calculation unit).

The first sheet stacking unit 11 stacks sheets to be sent to the image forming unit.
The second sheet stacking unit 12 stacks sheets on which images are formed by the image forming unit.
The sheet feeding unit 13 feeds a sheet to the sheet conveyance path 14.
The sheet conveyance path 14 sends the sheet to the image forming unit 2 and discharges the sheet on which the image forming unit 2 has formed an image to the second sheet stacking unit 12.

The fixing device 15 heats and presses the sheet on which the image forming unit 2 has formed an image, and fixes the image on the sheet.
The display unit 16 is a touch panel or the like, and displays setting information, operation status, log information, and notification to the user of the image forming apparatus 1.
The operation input unit 17 is a touch panel or a hard key, and receives an instruction of a functional operation of the image forming apparatus 1 such as start of an image forming process by receiving a user's operation input.

  The control unit 18 includes a processor, an ASIC (Application Specific Integrated Circuit), a memory, and an HDD (Hard Disk Drive), and controls the entire image forming apparatus 1. The processor implements various functions by executing programs stored in the memory and the HDD. The ASIC is a dedicated circuit for realizing a specific function, and may have an appropriate function realized by the processor.

The image forming unit 2 forms an image on a sheet using toner. The image forming unit 2 includes a laser unit 21, a photosensitive member 22, a developing device 23, a transfer belt 24, a toner bottle 25, a toner conveyance path 26, an exchange detection sensor 27, and a measuring unit 3.
The laser unit 21 exposes the photosensitive surface on the photosensitive member 22 and forms an electrostatic latent image on the photosensitive surface.

  The outer peripheral surface of the photosensitive member 22 is a photosensitive surface such as an OPC (Organic Photo Conductor). An electrostatic latent image is formed on the photosensitive surface by the laser unit 21. The electrostatic latent image is developed by the developing device 23 to become a toner image. The photoreceptor 22 carries the toner image on the photosensitive surface and transfers it onto the transfer belt 24.

The developing device 23 contains a two-component developer composed of toner and carrier. The developing device 23 develops the electrostatic latent image on the photoreceptor 22 using toner. The developing device 23 includes an auto toner sensor that detects the toner concentration in the developer. As the auto toner sensor, for example, a magnetic type that detects a change in magnetic permeability can be used.
The transfer belt 24 transfers the toner image to the sheet.

  The toner bottle 25 stores toner. When the toner concentration in the developing device 23 decreases, the toner bottle 25 supplies toner to the developing device 23 via the measuring unit 3 until the toner concentration exceeds a threshold value. Thereby, the toner density in the developing device 23 is kept constant.

The toner bottle 25 includes a bottle housing (not shown), a discharge opening, an auger screw, and a toner motor. The bottle housing has a longitudinal shape and accommodates toner therein. The discharge opening is on one end side in the longitudinal direction of the bottle housing, and discharges the toner to the developing unit 23 side. The toner motor rotates the auger screw. The auger screw is in the bottle housing and rotates to convey the toner to the discharge opening.
The replacement detection sensor 27 detects whether the toner bottle 25 is in a proper position, that is, detects replacement of the toner bottle 25.

FIG. 2 is a schematic diagram showing the toner conveyance path 26 and the measurement unit 3.
The toner conveyance path 26 is a path and sends the toner discharged from the toner bottle 25 to the developing unit 23.
The measuring unit 3 is in the middle of the toner conveyance path 26.

FIG. 3 is a perspective view showing an outline of the measuring unit 3.
The measuring unit 3 stores a predetermined amount of toner discharged from the toner bottle 25 when the toner is supplied from the toner bottle 25 to the developing device 23, measures the predetermined amount of toner, and discharges the predetermined amount of toner to the developing device 23. To do. That is, the measuring unit 3 discharges the toner to the developing unit 23 every time a predetermined amount of toner is stored from the toner bottle 25 when toner is supplied from the toner bottle 25 to the developing unit 23. Accordingly, in this embodiment, by adding up the number of discharges of the measuring unit 3, the amount of toner replenished by the toner bottle 25 can be calculated more accurately than in the past, and the remaining amount of toner in the toner bottle 25 can be calculated more accurately than in the past. Can be calculated.

The measurement unit 3 includes a storage unit 31 (first storage unit), first and second toner detection sensors 32 and 33, and first and second shutters 34 and 35.
The storage unit 31 can store a predetermined amount or more of toner. The container 31 includes a first wall surface 311 on the toner bottle 25 side and a second wall surface 312 on the developing device 23 side. The first wall surface 311 has a first opening 313 that is a supply path of toner from the toner bottle 25 side into the container 31. The second wall surface 312 has a second opening 314 that is a toner supply path from the inside of the container 31 to the developing device 23 side.

  The first toner detection sensor 32 detects whether or not there is a predetermined amount of toner in the storage unit 31. The first toner detection sensor 32 may have any configuration as long as the detection is possible. For example, the first toner detection sensor 32 detects whether the toner surface in the storage unit 31 is at a predetermined height. The first toner detection sensor 32 is of a transmissive type, a light emitting part that emits light horizontally at a predetermined height position, and a transmission window that is provided on the wall surface of the housing part 31 so as to face the light emitting part. And a light receiving part for receiving light from the light emitting part through the transmission window. The first toner detection sensor 32 detects that the toner surface is at a predetermined height when the light reception intensity of the light receiving unit is equal to or less than a threshold value.

  The second toner detection sensor 33 detects whether there is toner in the container 31. The second toner detection sensor 33 is below the first toner detection sensor 32 and is near the second wall surface 312. Similarly to the first toner detection sensor 32, the second toner detection sensor 33 may be a transmissive type.

  The first shutter 34 is slid by a drive mechanism (not shown), and opens and closes a first opening 313 that is a toner supply path from the toner bottle 25 side into the storage unit 31. The first shutter 34 closes the first opening 313 when the first toner detection sensor 32 detects that the toner in the storage unit 31 reaches a predetermined amount.

  The second shutter 35 slides by a drive mechanism (not shown), and opens and closes the second opening 314 that is a toner supply path from the inside of the storage unit 31 to the developing device 23 side. The second shutter 35 opens the second opening 314 when the first toner detection sensor 32 detects that the toner in the storage unit 31 reaches a predetermined amount when toner is supplied from the toner bottle 25 to the developing device 23.

FIG. 4 is a flowchart showing preparatory operation control of the measurement unit 3 by the control unit 18 when the toner bottle 25 is replaced with a new one.
When the replacement detection sensor 27 detects the replacement of the toner bottle 25, the control unit 18 uses the second toner detection sensor 33 to check whether there is toner in the storage unit 31 (Act 11). When there is toner in the storage unit 31 (Act 11: YES), the control unit 18 closes the first shutter 34 side, opens the second shutter 35 side, and discharges the toner in the storage unit 31 to the developing device 23. (Act12).

  When the toner in the storage unit 31 is not present when the replacement of the toner bottle 25 is detected (Act 11: NO), and the toner in the storage unit 31 is discharged, the control unit 18 runs out of toner in the storage unit 31. If it is confirmed that this is the case (Act 13: YES), the first shutter 34 on the toner bottle 25 side is opened and the second shutter 35 on the developing unit 23 side is closed. Then, the control unit 18 drives the toner motor to discharge the toner from the toner bottle 25 to the measuring unit 3 (Act 14).

  When the first toner detection sensor 32 detects that a predetermined amount of toner has been discharged to the measurement unit 3 (Act 15: YES), the control unit 18 stops driving the toner motor and transfers the toner from the toner bottle 25 to the measurement unit 3. Stops toner discharge. Further, the control unit 18 closes the first shutter 34 on the toner bottle 25 side, and puts the measurement unit 3 in a standby state in which a predetermined amount of toner is accommodated (Act 16).

FIG. 5 is a flowchart showing a toner replenishing process from the toner bottle 25 to the developing device 23 by the control unit 18.
Assume that the measuring unit 3 is in a standby state in which a predetermined amount of toner is accommodated as described above.
The control unit 18 is ready for the image forming apparatus 1 when the toner bottle 25 is replaced (after the measuring unit 3 is put into a standby state), during a print job of the image forming apparatus 1, or between print jobs. When the auto toner sensor detects that the toner density in the developing device 23 falls below the threshold value during the state (Act 21: Yes), the second shutter 35 on the developing device 23 side is opened, and the measuring unit 3 supplies toner to the developing device 23. A predetermined amount is discharged (Act 22).

  When the second toner detection sensor 33 detects that a predetermined amount of toner has been discharged from the measurement unit 3 (Act 23: YES), the control unit 18 increments the toner replenishment count by 1 (Act 24). The control unit 18 opens the first shutter 34 on the toner bottle 25 side again and closes the second shutter 35 on the developing unit 23 side. Then, the control unit 18 drives the toner motor to discharge the toner from the toner bottle 25 to the measuring unit 3 (Act 25).

  When the first toner detection sensor 32 detects that a predetermined amount of toner has been discharged to the measurement unit 3 (Act 26: YES), the control unit 18 stops driving the toner motor and transfers the toner from the toner bottle 25 to the measurement unit 3. Stops toner discharge. The control unit 18 closes the first shutter 34 on the toner bottle 25 side, and puts the measurement unit 3 in a standby state containing a predetermined amount of toner (Act 27).

  The control unit 18 repeats Act22 to Act28 until the toner density in the developing device 23 exceeds the threshold value and the toner density is restored to a specified state (Act28: NO). That is, the control unit 18 repeatedly measures the toner from the toner bottle 25 by a predetermined amount by the measuring unit 3 and supplies the predetermined amount of toner to the developing device 23 until the toner density is restored to a specified state. .

  The control unit 18 assumes that the toner storage amount of the toner bottle 25 is A, the predetermined amount of toner stored in the measurement unit 3 is B, and the number of times of replenishment of toner to the developing device 23 by the measurement unit 3 is N. The remaining amount of toner is calculated by A-NB. The control unit 18 displays the remaining toner amount on the display unit 16 based on the calculated remaining toner amount (Act 29).

Note that the method for displaying the remaining amount of toner may be appropriate. For example, when the near empty amount, which is a predetermined toner amount that causes the toner remaining amount in the toner bottle 25 to be small, is r, the control unit 18 satisfies the case where A−NB> r, that is, the toner remaining amount in the toner bottle 25. If the value does not decrease to the near empty amount, nothing needs to be displayed on the display unit 16. When A−NB <r, that is, when the remaining amount of toner in the toner bottle 25 is reduced to the near empty amount, the control unit 18 displays on the display unit 16 that the remaining amount of toner in the toner bottle 25 is small. May be.
The controller 18 may provide a plurality of threshold values for the remaining amount of toner and display the remaining amount of toner in detail.
Further, when the toner bottle 25 is replaced with a new one, the control unit 18 resets the toner replenishment count N to zero.

  When measuring the toner discharged from the toner bottle 25 (Act22 to Act28: NO), the control unit 18 cannot detect that the predetermined amount of toner is discharged to the measuring unit 3 by the first toner detection sensor 32 within a predetermined time. In the case (Act 30: YES), it is determined that the toner in the toner bottle 25 is empty. In this case, the control unit 18 displays on the display unit 16 that the toner bottle 25 is toner empty (Act 31). The predetermined time can be freely set.

  As described above, in this embodiment, when the toner is supplied from the toner bottle 25 to the developing device 23, the toner is supplied to the developing device 23 while the measuring unit 3 measures the toner by a predetermined amount. Therefore, in the present embodiment, the amount of toner replenished to the developing device 23 can be calculated more accurately than before, and the remaining amount of toner in the toner bottle 25 can be calculated more accurately than before.

(Second Embodiment)
FIG. 6 is a perspective view showing an outline of the measurement unit 3A, and FIGS. 7 and 8 are schematic views showing a toner measurement operation by the measurement unit 3A.
The measuring unit 3A includes a columnar portion 36 that is driven to rotate about a central axis by a drive mechanism (not shown), and a concave accommodating portion 31A that extends in the central axis direction and can accommodate a predetermined amount of toner on the outer peripheral surface of the cylindrical portion. 2nd accommodating part) and the wall surface part 37 (FIG. 7) which covers the outer peripheral surface of the cylindrical part 36 are provided.

  As shown in FIG. 7, the wall surface portion 37 includes first and second openings 371 and 372. The first opening 371 communicates with the inside of the toner bottle 25 and supplies the toner from the toner bottle 25 to the storage unit 31A. The second opening 372 communicates with the inside of the developing device 23 via the toner conveyance path 26, and is for sending the toner stored in the storage portion 31A to the developing device 23 side.

The control unit 18 positions the storage unit 31A at the position shown in FIG. 7 that communicates with the toner bottle 25 in a normal state, and puts the measurement unit 3A in a standby state.
When the controller 18 detects the replacement of the toner bottle 25, the cylindrical portion 36 is rotated, and the toner in the container 31A is developed by passing the container 31A through the position shown in FIG. It discharges to the container 23 side, and the inside of the accommodating part 31A is emptied. Thereafter, the controller 18 stops the rotation of the cylindrical portion 36 at the position of FIG. 7 where the accommodating portion 31A communicates with the toner bottle 25, and puts the measuring portion 3A in a standby state.

FIG. 9 is a flowchart showing toner supply processing from the toner bottle 25 to the developing unit 23 by the control unit 18.
When the toner density in the developing device 23 falls below the threshold (Act 41: Yes), the control unit 18 drives the toner motor to discharge the toner from the toner bottle 25 (Act 42).

At the same time, the controller 18 rotates the cylindrical portion 36 and replenishes the developing device 23 while measuring the toner by a predetermined amount by the accommodating portion 31A (Act 43).
The control unit 18 repeats Act 46: NO, Act 42, and Act 43 until the toner density in the developing device 23 recovers to a specified state (Act 44: NO).

  The control unit 18 calculates the number N of toner replenishment to the developing device 23 by the measurement unit 3 based on the number of rotations of the cylindrical unit 36. As in the first embodiment, the control unit 18 calculates the remaining amount of toner in the toner bottle 25 based on the number of times of toner replenishment N by the measuring unit 3, and displays the remaining toner amount on the display unit 16 based on the calculated remaining toner amount. Is displayed (Act 45). As in the first embodiment, the control unit 18 may display that the toner bottle 25 is empty when the remaining amount of toner in the toner bottle 25 becomes small (A−NB <r). It is.

  In addition, when the toner is supplied to the developing device 23 while measuring the toner by a predetermined amount (Act 42 to Act 44), the control unit 18 does not increase the toner density in the developing device 23 even after a predetermined time (Act 46: Yes). The display unit 16 displays that the toner bottle 25 is toner empty (Act 47).

  Also in this embodiment, since the toner from the toner bottle 25 is replenished to the developing unit 23 while measuring the predetermined amount by the measuring unit 3, the remaining amount of toner in the toner bottle 25 can be calculated more accurately than before.

FIG. 10 is a schematic front view showing a measurement unit 3B according to a modification.
As shown in FIG. 10, a plurality of accommodating portions 31 </ b> B may be provided on the outer peripheral surface of the cylindrical portion 36 at equal intervals in the circumferential direction.

(Modification)
The order of the processes in the embodiment may be different from the order exemplified in the embodiment.
The present invention can be implemented in various other forms without departing from the spirit or main features thereof. Therefore, the above-described embodiment is merely an example in all respects and should not be interpreted in a limited manner. The scope of the present invention is indicated by the scope of claims, and is not restricted by the text of the specification. Further, all modifications, various improvements, alternatives and modifications belonging to the equivalent scope of the claims are all within the scope of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 3 ... Measurement part, 14 ... Sheet conveyance path, 16 ... Display part, 18 ... Control part (remaining amount calculation part), 22 ... Photoconductor, 23 ... Developer, 25 ... Toner bottle, 31 ... Accommodating part (first accommodating part), 31A ... accommodating part (second accommodating part), 32 ... first toner detection sensor (sensor), 34 ... first shutter, 35 ... second shutter, 36 ... cylindrical part, 37 ... Wall surface part, 371 ... 1st opening part, 372 ... 2nd opening part.

Claims (3)

A photoreceptor carrying an electrostatic latent image on the photosensitive surface;
A developing unit for developing the electrostatic latent image using toner;
A toner bottle for supplying toner to the developing device;
The toner toner bottle discharges a predetermined amount containing toner to a predetermined amount measured, and a measuring portion for discharging the toner of the predetermined amount to the developing device,
The measuring unit is
A first accommodating portion capable of accommodating the predetermined amount of toner;
A sensor for detecting whether or not the toner in the first container has reached the predetermined amount;
A first shutter that opens and closes a toner supply path from the toner bottle side to the first storage unit, and the toner detects that the toner in the first storage unit reaches the predetermined amount. A first shutter that closes the supply path from the bottle side;
A second shutter that opens and closes a toner supply path from the inside of the first storage unit to the developing device, and when the sensor detects that the amount of toner in the first storage unit reaches the predetermined amount, the developing unit A second shutter that opens the supply path to the container side . The apparatus of claim 1.
A remaining amount calculation unit that calculates the remaining amount of toner in the toner bottle based on the number of times of replenishment of toner to the developer by the measurement unit;
A display unit for displaying a remaining toner amount based on the remaining toner amount calculated by the remaining amount calculating unit;
An image forming apparatus comprising: The apparatus of claim 2.
The remaining amount calculation unit is configured such that the toner storage amount of the toner bottle is A, the predetermined amount of toner stored in the measurement unit is B, the number of times of toner replenishment by the measurement unit is N, and the toner near the toner bottle An image forming apparatus that, when the empty amount is r, determines that near empty when A−NB <r, and the display unit displays that the toner bottle is near empty.

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