JP6332136B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus equipped with a collection container for collecting waste toner collected without being transferred to a sheet.

  Conventionally, there is an image forming apparatus that develops an electrostatic latent image formed on the surface of an image carrier into a toner image and transfers the toner image to a sheet. In such an image forming apparatus, of the toner supplied to the image carrier, waste toner that has not been transferred to the paper is removed from the image carrier and collected. The recovered waste toner is stored in a predetermined recovery container.

  Here, if the waste toner is continuously collected even after the amount of waste toner in the collection container becomes full (full state), inconvenience such as leakage of the waste toner occurs. Therefore, for example, the image forming apparatus is provided with a full detection sensor for detecting that the amount of waste toner in the collection container is full. When the collection container becomes full, printing is stopped to prevent leakage of waste toner.

  Conventionally, in addition to the full detection sensor, there is an image forming apparatus provided with a near full detection sensor for detecting that the amount of waste toner in the storage container has become a near full state that is smaller than the full state ( For example, see Patent Document 1). Thus, in the image forming apparatus provided with the near full detection sensor, it is possible to notify the user that the near full state has been reached before the container is full (when the near full state is reached).

JP 2007-264448 A

  In the configuration provided with the near full detection sensor and the full detection sensor, if the user is notified that the near full state has been reached, the storage container will be placed before the storage container becomes full (before printing cannot be performed). It is possible to make the user recognize that it is necessary to exchange Therefore, in this configuration, since a new container can be prepared before the user cannot perform printing, this configuration is convenient.

  Here, when the near full detection sensor and the full detection sensor are used, it is possible to accurately detect the near full state and the full state. However, when using a near full detection sensor and a full detection sensor, it is necessary to secure the installation space for two sensors. In addition, there is a disadvantage that the cost increases.

  For this reason, a full detection sensor may be abbreviate | omitted among a near full detection sensor and a full detection sensor, for example. However, in this case, it becomes impossible to detect that the collection container is full. Therefore, in order to prevent leakage of waste toner, printing must be stopped when the near full state is reached (before the collection container is full).

  The present invention has been made to solve the above-described problems, and can accurately detect whether or not the amount of waste toner in the container has become full without using a full detection sensor. An object is to provide an image forming apparatus.

  In order to achieve the above object, an image forming apparatus of the present invention is detachable from a developing device that develops an electrostatic latent image based on image data formed on an image carrier with toner, and the image forming device. A collection container for storing waste toner collected without being transferred to the paper out of the toner supplied to the image carrier from the apparatus, and a near-full amount of waste toner in the collection container being smaller by a predetermined amount than a predetermined full state A near full detection sensor for detecting whether or not a state has occurred, a storage container for storing toner for replenishment, and a storage container for supplementing the consumed toner when the toner in the developing device is consumed A replenishing member that replenishes the toner stored in the developing device, a transfer toner amount that is a toner amount transferred to the paper, a replenishing toner amount that is a toner amount replenished from the housing container to the developing device, and And a control unit for calculating a collected toner amount is the amount of toner recovered in the recovery container. Then, the control unit detects whether or not the near full state is reached based on the output value of the near full detection sensor, and subtracts the transfer toner amount after the near full state from the replenishment toner amount after the near full state is reached. The calculated value obtained by this is obtained as the amount of collected toner after reaching the near full state. When the amount of collected toner after reaching the near full state exceeds a predetermined amount, it is determined that the full state is reached.

  In the configuration of the present invention, when the toner in the developing device is consumed, the toner contained in the container is replenished to the developing device in order to supplement the reduced amount of toner. That is, the replenishment toner amount at the time of printing based on the predetermined image data corresponds to the toner amount (consumed toner amount) supplied from the developing device to the image carrier at the time of printing based on the predetermined image data. Of the toner supplied from the developing device to the image carrier at the time of printing based on predetermined image data, the toner corresponding to the transfer toner amount is transferred to the paper, and the remaining toner is collected in the collection container. Therefore, a calculated value obtained by subtracting the transfer toner amount after the near full state is obtained from the replenishment toner amount after the near full state is obtained and becomes the recovered toner amount after the near full state.

  Therefore, the control unit obtains a calculated value obtained by subtracting the transfer toner amount after becoming the near full state from the replenishment toner amount after becoming the near full state as the recovered toner amount after becoming the near full state. The near full state is a state in which the amount of waste toner is smaller than the full state by a predetermined amount. Therefore, when the collected toner amount after the near full state exceeds the predetermined amount, the amount of waste toner in the collection container Is determined to be full. Thereby, it is possible to accurately detect whether or not the amount of waste toner in the collection container is full without using a full detection sensor.

  As described above, in the configuration of the present invention, it is possible to accurately detect whether or not the amount of waste toner in the storage container is full without using a full detection sensor.

1 is a schematic diagram illustrating an example of a multifunction peripheral according to an embodiment of the present invention. Schematic which shows an example of the container with which the multifunctional device by one Embodiment of this invention is mounted | worn. 1 is a schematic diagram illustrating an example of a waste toner box mounted on a multifunction machine according to an embodiment of the present invention. 1 is a block diagram showing an example of a hardware configuration of a multifunction machine according to an embodiment of the present invention. 6 is a flowchart for explaining the flow of processing when detecting the amount of waste toner in the waste toner box in the multifunction machine according to the embodiment of the present invention.

  An embodiment of the present invention will be described with reference to a multi-function peripheral equipped with a plurality of functions such as a copy function.

<Overall configuration of MFP>
As illustrated in FIG. 1, the multifunction peripheral 100 (corresponding to an “image forming apparatus”) includes an image reading unit 1 and a printing unit 2. The image reading unit 1 reads a document and generates image data. The printing unit 2 transports the paper P along the paper transport path 20 and forms a toner image based on image data of an image to be printed on the paper P. Then, the printing unit 2 transfers (prints) the toner image onto the paper P being conveyed.

  The printing unit 2 includes a paper feeding unit 3, a paper transport unit 4, an image forming unit 5, and a fixing unit 6. The paper feed unit 3 includes a pickup roller 31 and a paper feed roller pair 32 and supplies the paper P stored in the paper cassette 21 to the paper transport path 20. The paper transport unit 4 includes a plurality of transport roller pairs 41 and transports the paper P along the paper transport path 20.

  The image forming unit 5 includes a photosensitive drum 51, a charging device 52, an exposure device 53, a developing device 54, a transfer roller 55, and a cleaning device 56. The photosensitive drum 51 corresponds to an “image carrier”.

  At the time of image formation, the photosensitive drum 51 rotates, and the charging device 52 charges the surface of the photosensitive drum 51. Further, the exposure device 53 exposes the surface of the photosensitive drum 51 and forms an electrostatic latent image on the surface of the photosensitive drum 51 based on image data of an image to be printed on the paper P. The developing device 54 supplies toner toward the surface of the photosensitive drum 51 to develop the electrostatic latent image into a toner image. The transfer roller 55 is in pressure contact with the surface of the photoconductive drum 51 and forms a transfer nip with the photoconductive drum 51. As the paper P enters the transfer nip, the toner image on the surface of the photosensitive drum 51 is transferred to the paper P.

  Here, the developing device 54 of the image forming unit 5 stores toner. However, since the toner in the developing device 54 is consumed by the execution of printing, it is necessary to supply toner to the developing device 54. For this reason, the multi-function device 100 is equipped with a container 200 that stores toner for supply. When the remaining amount of toner in the developing device 54 falls below a predetermined reference amount, toner supply from the container 200 to the developing device 54 is performed. The container 200 corresponds to a “container”.

  The container 200 is detachable (replaceable) with respect to the multifunction device 100. For example, a part of the exterior cover of the multifunction device 100 is an opening / closing cover (not shown), and the opening / closing cover is opened to expose a space for mounting the container 200. As a result, when the toner in the container 200 runs out, the container 200 can be replaced with a new container 200.

  In order to supply toner from the container 200 to the developing device 54, the container 200 is provided with a supply screw 71 as shown in FIG. Alternatively, the replenishing screw 71 is provided in the main body of the multifunction peripheral 100. The supply screw 71 corresponds to a “supply member”. Further, when the container 200 is mounted on the multifunction peripheral 100, the container 200 and the developing device 54 are connected by the supply pipe 72.

  The supply screw 71 has, for example, a structure in which blades are spirally wound around a rotation shaft, and rotates when a driving force is transmitted from the supply motor M1 (see FIG. 4). When toner is supplied from the container 200 to the developing device 54, the toner in the container 200 falls from the container 200 as the supply screw 71 rotates. The toner dropped from the container 200 is supplied to the developing device 54 via the supply pipe 72.

  Returning to FIG. 1, the cleaning device 56 of the image forming unit 5 is the toner remaining on the surface of the photosensitive drum 51 without being transferred to the paper P among the toner supplied from the developing device 54 to the surface of the photosensitive drum 51. And are accumulated in a waste toner box 300 (see FIG. 3) described later. That is, the toner remaining on the surface of the photosensitive drum 51 without being transferred to the paper P is collected in the waste toner box 300. The toner collected in the waste toner box 300 is a discarded toner, and is referred to as a waste toner in the following description.

  The cleaning device 56 is provided with a cleaning roller 57. The cleaning roller 57 is rotatable about a rotation shaft extending in parallel with the rotation axis direction of the photosensitive drum 51 and is in contact with the surface of the photosensitive drum 51. The cleaning roller 57 rotates in the same direction as the photosensitive drum 51 when the photosensitive drum 51 rotates (when a toner image is formed). As a result, the cleaning roller 57 rubs the surface of the photoconductive drum 51 when the photoconductive drum 51 rotates, so that waste toner remaining on the surface of the photoconductive drum 51 is scraped off. In addition, instead of the cleaning roller 57, a resin blade or brush is provided in the cleaning device 56, and the waste toner remaining on the surface of the photosensitive drum 51 is brought into contact with the surface of the photosensitive drum 51 by bringing the blade or brush into contact with the surface of the photosensitive drum 51. You may make it scrape.

  Further, the cleaning device 56 is provided with a toner conveying member 58 for conveying the waste toner scraped off by the cleaning roller 57. The toner conveying member 58 has, for example, a rotating shaft of the cleaning roller 57 and a rotating shaft extending in a change manner. A spiral blade wound spirally is integrally formed around the rotation shaft. The toner conveying member 58 rotates with the cleaning roller 57 and conveys the waste toner scraped off by the cleaning roller 57 to one side in the rotation axis direction. A discharge pipe (not shown) is provided on one side of the toner conveying member 58 in the rotation axis direction. For this reason, the waste toner scraped off by the cleaning roller 57 is discharged to the discharge pipe.

  The discharge pipe provided in the cleaning device 56 is connected to a waste toner box 300 as shown in FIG. Thereby, the waste toner discharged from the cleaning device 56 is guided to the waste toner box 300 via the discharge pipe. The waste toner box 300 corresponds to a “collection container”.

  The waste toner box 300 is provided with a pipe portion 300 a having a receiving port (opening) for receiving waste toner discharged from the cleaning device 56. Further, the waste toner box 300 (including the pipe portion 300a) detects the amount of waste toner in the waste toner box 300 by the near full detection sensor 130 (light sensor) disposed outside the waste toner box 300, and thus transmits light. Made of a conductive material (for example, a translucent resin).

  The waste toner box 300 is detachable (replaceable) with respect to the multifunction peripheral 100. For example, a part of the exterior cover of the multifunction peripheral 100 is an open / close cover (not shown), and when the open / close cover is opened, a space for mounting the waste toner box 300 is exposed. Accordingly, when the amount of waste toner accumulated in the waste toner box 300 becomes full, the waste toner box 300 can be replaced with a new waste toner box 300 (empty waste toner box 300).

  Returning to FIG. 1, the fixing unit 6 includes a heating roller 61 and a pressure roller 62. The heating roller 61 has a built-in heat source. The pressure roller 62 is in pressure contact with the heating roller 61 and forms a fixing nip with the heating roller 61. The paper P on which the toner image is transferred is heated and pressurized by passing through the fixing nip. As a result, the toner image is fixed on the paper P and printing is completed.

  The multifunction device 100 also includes an operation panel 7. The operation panel 7 includes a liquid crystal display panel 71 with a touch panel. The liquid crystal display panel 71 displays soft keys and messages for accepting various settings. Alternatively, the liquid crystal display panel 71 displays information indicating the device state. The operation panel 7 is also provided with hard keys 72 such as a start key and a numeric keypad.

  For example, when the amount of waste toner accumulated in the waste toner box 300 becomes a near full state that is a predetermined amount less than the full state, the operation panel 7 notifies the user that the waste toner box 300 is in the near full state ( A message for prompting replacement of the waste toner box 300).

<Hardware configuration of MFP>
As illustrated in FIG. 4, the multifunction peripheral 100 includes a control unit 110. The control unit 110 includes a CPU 111, an image processing unit 112, and a storage unit 113. The image processing unit 112 includes an ASIC dedicated to image processing, and performs various image processing (enlargement / reduction, density conversion, data format conversion, etc.) on the image data. The storage unit 113 includes a ROM and a RAM. The storage unit 113 stores a control program and data. The control unit 110 controls the operation of each unit of the multifunction peripheral 100 based on the control program and data stored in the storage unit 113.

  Specifically, the control unit 110 is connected to the image reading unit 1 and controls the reading operation of the image reading unit 1. The control unit 110 is connected to the printing unit 2 (the paper feeding unit 3, the paper transport unit 4, the image forming unit 5, and the fixing unit 6) and controls the printing operation of the printing unit 2. Furthermore, the control unit 110 is connected to the operation panel 7 and controls the display operation of the operation panel 7 or detects an operation performed on the operation panel 7.

  Here, the controller 110 is connected to a remaining amount detection sensor 120 for detecting the remaining amount of toner in the developing device 54. Although this remaining amount detection sensor 120 is not specifically limited, For example, it is an optical sensor which has a light emission part and a light-receiving part. Then, the control unit 110 detects the remaining amount of toner in the developing device 54 based on the output value of the remaining amount detection sensor 120, and determines whether or not toner replenishment from the container 200 to the developing device 54 is necessary. When the controller 110 determines that toner replenishment is necessary, the controller 110 drives the replenishment motor M1. As a result, the replenishing screw 71 rotates and the toner is replenished from the container 200 to the developing device 54 (the toner in the container 200 is dropped by the rotation of the replenishing screw 71).

  For example, the control unit 110 detects whether or not the remaining amount of toner in the developing device 54 is below a predetermined reference amount based on the output of the remaining amount detection sensor 120. Then, when the remaining amount of toner in the developing device 54 falls below the reference amount, the control unit 110 determines that toner supply is necessary, and drives the supply motor M1 (rotates the supply screw 71). That is, the control unit 110 causes the toner supply from the container 200 to the developing device 54 to be performed. Thereafter, when the remaining amount of toner in the developing device 54 exceeds the reference amount, the control unit 110 stops toner supply from the container 200 to the developing device 54.

  Further, a near full detection sensor 130 for detecting the amount of waste toner in the waste toner box 300 is connected to the control unit 110. The near full detection sensor 130 is an optical sensor having a light emitting unit 131 and a light receiving unit 132. The light receiving unit 131 and the light emitting unit 132 are arranged to face each other with the waste toner box 300 interposed therebetween (see FIG. 3). The light emitting unit 131 emits light toward the waste toner box 300. The light emitted from the light emitting unit 131 passes through the waste toner box 300. The light receiver 132 receives the light transmitted through the waste toner box 300 and changes the output value according to the amount of received light.

  For example, if the waste toner accumulated in the waste toner box 300 has not reached the detection position of the near-full detection sensor 130 (the position of the optical path between the light emitting unit 131 and the light receiving unit 132), the amount of light received by the light receiving unit 132 increases. . On the other hand, when the waste toner accumulated in the waste toner box 300 reaches the vicinity of the detection position of the near full detection sensor 130, the amount of light received by the light receiving unit 132 decreases.

  Then, the control unit 110 detects whether the amount of waste toner accumulated in the waste toner box 300 is in a near-full state based on the output value of the near-full detection sensor 130. For example, the output value of the near full detection sensor 130 when the waste toner accumulated in the waste toner box 300 reaches the detection position of the near full detection sensor 130 is obtained in advance, and the value is set as a threshold value. Then, based on whether the output value of the near-full detection sensor 130 exceeds (or falls below) the threshold value, the control unit 110 determines whether or not the amount of waste toner accumulated in the waste toner box 300 is in a near-full state. Is detected. The near full state is a state where the amount of waste toner accumulated in the waste toner box 300 is smaller by a predetermined amount than a predetermined full state (full state).

  Further, the control unit 110 calculates a replenishment toner amount that is a toner amount replenished from the container 200 to the developing device 54. Further, the control unit 110 calculates a transfer toner amount that is a toner amount transferred to the paper P during printing. As will be described in detail later, the replenishment toner amount and the transfer toner amount are used to detect whether or not the waste toner amount in the waste toner box 300 is full (full state).

  The controller 110 counts the number of rotations of the replenishment screw 71 during toner replenishment in order to calculate the replenishment toner amount. Then, the control unit 110 obtains a replenishment toner amount based on the number of rotations of the replenishment screw 71. Here, the replenishing screw 71 drops a substantially constant amount of toner from the container 200 to the developing device 54 per one rotation. In other words, a target value for the toner fall amount per rotation of the replenishing screw 71 (the amount of toner replenished to the developing device 54 when the replenishing screw 71 rotates once) is determined in advance, and the replenishing screw is set to the target value. The shape and installation position of 71 are designed. Therefore, the amount of toner to be supplied at the time of toner supply can be obtained based on the number of rotations of the supply screw 71 at the time of toner supply (the amount of toner fall per rotation of the supply screw 71 can be multiplied by the number of rotations of the supply screw 71. Just fine).

  The container 200 is provided with, for example, an IC tag 200a as a storage medium. Then, the control unit 110 causes the IC tag 200a to store replenishment amount data that is a cumulative value of the replenishment toner amount after the container 200 is mounted on the multifunction peripheral 100.

  Further, when obtaining the transfer toner amount, the control unit 110 counts the number of print dots (the number of dots on which toner is applied) based on the image data to be printed. Then, the control unit 110 obtains a value obtained by multiplying the number of print dots by a predetermined toner consumption amount per dot as the transfer toner amount.

<Detection of waste toner amount in waste toner box>
The control unit 110 detects whether the amount of waste toner in the waste toner box 300 is in a near full state based on the output value of the near full detection sensor 130. When it is detected that the waste toner box 300 is in the near full state, the control unit 110 causes the operation panel 7 to display a message or the like for prompting the user to replace the waste toner box 300. Accordingly, it is possible to prompt the user to replace the waste toner box 300 before the waste toner box 300 becomes full.

  However, even if the user is prompted to replace the waste toner box 300, the waste toner box 300 may not be replaced. In this case, if the waste toner is continuously collected, the waste toner box 300 becomes full, and the waste toner box 300 cannot store the waste toner. Therefore, after the waste toner box 300 becomes near full, the control unit 110 determines whether the waste toner box 300 becomes full, and if it determines that the waste toner box 300 becomes full, the control unit 110 is executing. Printing is stopped (print execution instruction is not accepted).

  Here, when printing based on predetermined image data is executed, toner in the developing device 54 is supplied to the photosensitive drum 51 (toner in the developing device 54 is consumed). For this reason, the remaining amount of toner in the developing device 54 decreases. When the toner in the developing device 54 is consumed and the remaining amount of toner in the developing device 54 decreases, the control unit 110 supplies toner from the container 200 to the developing device 54 in order to compensate for the decreased amount of toner ( The supply screw 71 is rotated). Accordingly, the amount of toner to be supplied at this time corresponds to the amount of toner reduced by printing (the amount of toner supplied to the photosensitive drum 51).

  Of the toner supplied to the photosensitive drum 51 when printing based on predetermined image data (toner for the replenishment toner amount), the toner for the transfer toner amount calculated based on the predetermined image data is the paper P Is transcribed. The toner that has not been transferred to the paper P is collected in the waste toner box 300 as waste toner. Therefore, by subtracting the transfer toner amount from the toner amount supplied to the photosensitive drum 51 (replenishment toner amount), the amount of toner collected in the waste toner box 300 (hereinafter referred to as “removal toner amount”) when printing based on predetermined image data is performed. (Referred to as “recovered toner amount”).

  Therefore, in the present embodiment, a full detection sensor for detecting whether or not the waste toner box 300 is full is not provided, and the amount of collected toner after the waste toner box 300 becomes near full is calculated. It is determined whether or not the waste toner box 300 is full based on the calculated value.

  That is, the control unit 110 calculates the replenishment toner amount (cumulative value) after the near full state and calculates the transfer toner amount (cumulative value) after the near full state. Further, the control unit 110 obtains a calculated value obtained by subtracting the transfer toner amount after becoming the near full state from the replenishment toner amount after becoming the near full state as the recovered toner amount after becoming the near full state. . Since the waste toner amount is smaller by a predetermined amount than the full state in the near full state, the control unit 110 causes the waste toner box 300 to be full when the collected toner amount after the near full state exceeds a predetermined amount. Judge that it is in a state.

  However, the amount of toner fall per rotation of the supply screw 71 varies depending on the rotation speed of the supply screw 71 (for example, the rotation speed of the supply screw 71 may be set to the normal speed or may be lower than the normal speed). May be set). Further, the amount of toner fall per rotation of the replenishing screw 71 also varies depending on the type of toner (for example, viscosity). Further, the amount of toner falling per rotation of the replenishing screw 71 also varies depending on the installation environment (temperature, humidity, etc.) of the multifunction machine 100.

  Therefore, the toner fall amount per rotation of the replenishing screw 71 increases or decreases with respect to the target toner fall amount targeted at the design stage. For this reason, when the replenishment toner amount is calculated based on the target toner fall amount, there is a difference between the calculated replenishment toner amount and the actual replenishment toner amount. That is, there is a difference between the calculated value of the collected toner amount and the actual collected toner amount. As a result, there is an inconvenience that the control unit 110 determines that it is full even though it is not full, or that the control unit 110 does not determine full when it is full. There is a case.

  Therefore, the control unit 110 performs a predetermined correction process when calculating the collected toner amount after the near full state is reached. For example, as the correction process, the control unit 110 performs a process of correcting the calculated value of the replenishment toner amount used when calculating the collected toner amount after the near full state.

  In order to perform this correction processing, the storage unit 113 stores in advance a theoretical value of the amount of waste toner stored in the waste toner box 300 until the waste toner box 300 changes from an empty state to a near full state. This theoretical value is obtained based on the shape (volume) of the waste toner box 300 and the like.

  In addition, the control unit 110 supplies toner for a predetermined period after the waste toner box 300 is attached to the multifunction peripheral 100 in an empty state (new state) and until the waste toner box 300 changes from an empty state to a near full state. An amount (cumulative value for a predetermined period) and a transfer toner amount (accumulated value for a predetermined period) are calculated. Then, when the waste toner box 300 is in a near full state, the control unit 110 obtains a calculated value obtained by subtracting the transfer toner amount for a predetermined period from the replenishment toner amount for a predetermined period as the collected toner amount for the predetermined period. . When the amount of collected toner for a predetermined period is obtained, the control unit 110 compares the calculated value of the collected toner amount for a predetermined period with a theoretical value.

  As a result of the comparison, if the calculated value of the collected toner amount in the predetermined period is larger than the theoretical value, it means that the recovered toner amount in the predetermined period is estimated to be larger than the actual collected toner amount. Therefore, the amount of collected toner after the near full state is estimated to be larger than the actual amount of collected toner. Further, when the calculated value of the collected toner amount for the predetermined period is smaller than the theoretical value, it means that the recovered toner amount for the predetermined period is estimated to be smaller than the actual collected toner amount. Therefore, the amount of collected toner is estimated to be smaller than the actual amount of collected toner.

  For this reason, the smaller the calculated value of the collected toner amount for the predetermined period than the theoretical value, the greater the calculated value of the collected toner amount after the near-full state becomes, when the correction processing is not performed. Correction processing is performed. In addition, the controller 110 increases the calculated value of the collected toner amount for a predetermined period from the theoretical value so that the calculated value of the collected toner amount after the near full state becomes smaller than when the correction processing is not performed. Perform correction processing.

  First, when the waste toner box 300 is in a near full state, the control unit 110 obtains a ratio between the calculated value of the collected toner amount for a predetermined period and a theoretical value, and performs correction processing for performing correction processing based on the obtained ratio. Set the coefficient.

  For example, the control unit 110 sets the ratio of the theoretical value to the calculated value of the collected toner amount for a predetermined period as the correction coefficient. That is, when the calculated value of the collected toner amount for a predetermined period is T1, and the theoretical value is T2, the correction coefficient is T2 / T1. As an example, when the calculated value of the collected toner amount for a predetermined period is 90% of the theoretical value, the correction coefficient is 1.1. When the calculated value of the collected toner amount for a predetermined period is 110% of the theoretical value, the correction coefficient is 0.9.

  When the correction coefficient is set, the control unit 110 obtains the corrected toner fall amount by multiplying the target toner fall amount per rotation of the replenishing screw 71 by the correction coefficient. Thereafter, when the amount of replenishing toner after the near full state is obtained, the toner fall amount per rotation multiplied by the number of rotations of the replenishment screw 71 is not the target toner fall amount but the target toner fall amount multiplied by the correction coefficient. Use the corrected toner fall amount.

  As a result, the smaller the calculated value of the collected toner amount for the predetermined period is, the larger the corrected toner fall value is than the target fall value. The calculated value of the toner amount becomes larger than that when the correction process is not performed. In addition, as the calculated value of the collected toner amount for a predetermined period is larger than the theoretical value, the corrected toner fall value becomes smaller than the target fall value, and as a result, the collected toner after becoming near full is collected. The calculated value of the amount is smaller than when the correction process is not performed.

  As the correction process, the calculated value of the recovered toner amount after the near full state may be corrected, or the transfer toner amount used when calculating the recovered toner amount after the near full state is corrected. May be performed. Alternatively, as the correction process, the calculated values of both the replenishment toner amount after the near full state and the transfer toner amount after the near full state may be corrected.

  When correcting the calculated value of the collected toner amount after the near full state is corrected, for example, the ratio of the theoretical value to the calculated value of the collected toner amount for a predetermined period is set as the correction coefficient. That is, the same correction coefficient as the correction coefficient used for correcting the calculated value of the replenishment toner amount after the near full state is used. As a result, the smaller the calculated value of the collected toner amount for the predetermined period is, the larger the calculated value of the collected toner amount after the near-full state is, when the correction process is not performed. Further, the larger the calculated value of the collected toner amount for the predetermined period is, the smaller the calculated value of the collected toner amount after the near-full state is obtained than when the correction process is not performed.

  When correcting the calculated value of the transfer toner amount after the near full state is corrected, for example, the smaller the calculated value of the collected toner amount for a predetermined period is, the smaller the theoretical value is, the smaller the transfer toner amount after the near full state is reached. When the calculated value is smaller than when correction processing is not performed and the calculated value of the collected toner amount for a predetermined period is larger than the theoretical value, the calculated value of the transferred toner amount after the near full state is corrected. The correction coefficient for correcting the transfer toner amount after the near full state is set so as to be larger than the case where the toner is not.

  Hereinafter, the flow of processing when detecting the amount of waste toner in the waste toner box 300 will be described with reference to the flowchart shown in FIG. The flowchart shown in FIG. 5 starts when the first printing is performed after the waste toner box 300 is installed in the multifunction device 100 in an empty state.

  In step S1, the control unit 110 calculates a replenishment toner amount and a transfer toner amount. The control unit 110 cumulatively adds the replenishment toner amount and cumulatively adds the transfer toner amount during a predetermined period until the waste toner box 300 changes from the empty state to the near full state.

  Here, when there is no toner in the developing device 54 (for example, when the multi-function device 100 is in a new state), the developing device from the container 200 until the toner amount in the developing device 54 reaches a predetermined reference amount. The toner is supplied to 54. After that, when printing is performed and the toner in the developing device 54 is consumed, toner supply from the container 200 to the developing device 54 is performed in order to supplement the consumed toner. Therefore, when toner is supplied to the developing device 54 from a state where there is no toner in the developing device 54, the amount of toner supplied to the developing device 54 until the toner amount in the developing device 54 reaches the reference amount is as follows. The controller 110 does not count the amount of replenished toner for a predetermined period.

  Next, in step S <b> 2, the control unit 110 determines whether the waste toner box 30 is in a near full state based on the output value of the near full detection sensor 130. If the result of this determination is that it is in the near full state, the process proceeds to step S3, and if it is not in the near full state, the process returns to step S1.

  In step S3, the control unit 110 calculates the recovered toner amount for a predetermined period by subtracting the transfer toner amount (cumulative value) for a predetermined period from the replenished toner amount (accumulated value) for a predetermined period. In step S4, the control unit 110 sets a correction coefficient for performing correction processing based on the ratio between the calculated value of the collected toner amount for a predetermined period and the theoretical value.

  The correction coefficient obtained here may be written in the IC tag 200a of the container 200. Then, when the toner is refilled in the used container 200 (container 200 in which the correction coefficient is written in the IC tag 200a) and the container 200 is attached to the multifunction device 100, the correction coefficient for performing the correction process. Alternatively, the correction coefficient written in the IC tag 200a may be used.

  Next, in step S5, the control unit 110 cumulatively adds the replenishment toner amount after the near full state is reached, and cumulatively adds the transfer toner amount after the near full state is reached. Further, at this time, the control unit 110 calculates a toner amount obtained by subtracting a transfer toner amount after becoming a near full state from a supply toner amount after becoming a near full state as a recovered toner amount after becoming a near full state. . The controller 110 uses the corrected toner fall amount obtained by multiplying the target toner fall amount per rotation of the replenishment screw 71 by the correction coefficient when calculating the replenishment toner amount after the near full state.

  Next, in step S6, the control unit 110 enters the near full state based on the calculated value of the collected toner amount after the near full state (the value obtained by correcting the calculated value of the replenished toner amount). Thereafter, it is determined whether or not the amount of collected toner after that exceeds a predetermined amount. If the result of this determination is that the amount of collected toner after reaching the near full state exceeds a predetermined amount (the amount of waste toner stored in the waste toner box 300 before the near full state becomes full), the process proceeds to step S7. If the collected toner amount after the near full state does not exceed the predetermined amount, the process returns to step S5.

  In step S7, the control unit 110 determines that the waste toner box 300 is full. In this case, the control unit 110 stops the printing being executed. The control unit 110 does not accept a print execution instruction until the waste toner box 300 is replaced.

  The multifunction peripheral 100 (image forming apparatus) according to this embodiment includes a developing device 54 that develops an electrostatic latent image based on image data formed on the photosensitive drum 51 (image carrier) with toner, and is attached to and detached from the multifunction peripheral 100. The waste toner box 300 (collection container) in which the waste toner collected without being transferred to the paper P among the toner supplied from the developing device 54 to the photosensitive drum 51 is collected, A near-full detection sensor 130 for detecting whether or not the amount of waste toner has reached a near-full state that is a predetermined amount less than a predetermined full state, a container 200 (container container) for storing replenishing toner, and a developing device When the toner in the toner supply 54 is consumed, a replenishing screw that replenishes the toner contained in the container 200 to the developing device 54 to supplement the consumed toner. (Replenishment member), transfer toner amount that is the amount of toner transferred to the paper P, replenishment toner amount that is the amount of toner replenished from the container 200 to the developing device 54, and the amount of toner collected in the waste toner box 300 And a control unit 110 that calculates the collected toner amount. Then, the control unit 110 detects whether or not the near full state has been reached based on the output value of the near full detection sensor 130, and changes the amount of transfer toner after the near full state from the replenishment toner amount after the near full state. The calculated value obtained by subtraction is obtained as the amount of collected toner after reaching the near full state, and when the amount of collected toner after reaching the near full state exceeds a predetermined amount, it is determined that the full state is reached.

  In the configuration of the present embodiment, when the toner in the developing device 54 is consumed, the toner contained in the container 200 is replenished to the developing device 54 in order to compensate for the reduced amount of toner. That is, the replenishment toner amount at the time of printing based on the predetermined image data corresponds to the toner amount (consumed toner amount) supplied from the developing device 54 to the photosensitive drum 51 at the time of printing based on the predetermined image data. Of the toner supplied from the developing device 54 to the photosensitive drum 51 during printing based on predetermined image data, the toner for the amount of transfer toner is transferred to the paper P, and the remaining toner is collected in the waste toner box 300. The Therefore, a calculated value obtained by subtracting the transfer toner amount after the near full state is obtained from the replenishment toner amount after the near full state is obtained and becomes the recovered toner amount after the near full state.

  Therefore, the control unit 110 obtains a calculated value obtained by subtracting the transfer toner amount after becoming the near full state from the replenishment toner amount after becoming the near full state as the recovered toner amount after becoming the near full state. . Since the near-full state is a state in which the amount of waste toner is smaller by a predetermined amount than in the full state, the control unit 110 causes the waste in the collection container when the amount of recovered toner after the near-full state exceeds a predetermined amount. It is determined that the toner amount is full. Accordingly, it is possible to accurately detect whether or not the amount of waste toner in the waste toner box 300 is full without using a full detection sensor.

  Further, in the present embodiment, as described above, the control unit 110 performs a predetermined period from when the waste toner box 300 is attached to the multifunction peripheral 100 in the empty state until the waste toner box 300 changes from the empty state to the near full state. During this period, the replenished toner amount and the transferred toner amount are calculated, and a calculated value obtained by subtracting the transferred toner amount for a predetermined period from the replenished toner amount for a predetermined period is obtained as a collected toner amount for a predetermined period, and the near full state When this happens, the calculated value of the collected toner amount for a predetermined period is compared with the theoretical value. Then, the controller 110 determines that the calculated value of the collected toner amount in the predetermined period is smaller than the theoretical value, and the calculated value of the collected toner amount after the near full state becomes larger than the case where the correction processing is not performed. The correction processing is performed so that the calculated value of the collected toner amount in the predetermined period becomes smaller than the theoretical value when the calculated value of the collected toner amount after the near-full state is larger than the theoretical value. By performing such correction processing, it is possible to accurately obtain the amount of collected toner after the near full state is reached. As a result, it is possible to more accurately detect whether or not the amount of waste toner in the waste toner box 300 is full.

  It should be thought that embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is shown not by the description of the above-described embodiment but by the scope of claims for patent, and further includes meanings equivalent to the scope of claims for patent and all modifications within the scope.

51 Photosensitive drum (image carrier)
54 Developing Device 71 Supply Screw (Supply Member)
110 Control unit 113 Storage unit 130 Near full detection sensor 200 Container (container)
300 Waste toner box (collection container)

Claims (5)

A developing device for developing an electrostatic latent image based on image data formed on the image carrier with toner;
A collection container that is detachable from the image forming apparatus and stores waste toner collected without being transferred to a sheet of toner supplied from the developing device to the image carrier;
A near full detection sensor for detecting whether or not the amount of waste toner in the recovery container has reached a near full state that is a predetermined amount less than a predetermined full state;
A storage container for storing toner for replenishment;
When the toner in the developing device is consumed, a replenishing member that replenishes the developing device with toner stored in the storage container in order to supplement the consumed toner.
Calculates the transfer toner amount that is the amount of toner transferred to the paper, the replenishment toner amount that is the amount of toner replenished from the storage container to the developing device, and the recovered toner amount that is the amount of toner collected in the recovery container A control unit,
A storage unit that stores a theoretical value of the amount of toner stored in the recovery container until the recovery container becomes empty from the empty state ;
The control unit detects whether or not the near full state has been reached based on an output value of the near full detection sensor, and the transfer after the near full state is changed to the near full state after the near full state is reached. A calculated value obtained by subtracting the toner amount is obtained as the collected toner amount after the near full state is reached, and when the collected toner amount after the near full state exceeds the predetermined amount, the full toner amount is obtained. Judge that it has become a state ,
The controller controls the replenishment toner amount and the transfer during a predetermined period after the collection container is attached to the image forming apparatus in the empty state until the collection container changes from the empty state to the near full state. The toner amount is calculated, and a calculated value obtained by subtracting the transfer toner amount for the predetermined period from the replenished toner amount for the predetermined period is obtained as the collected toner amount for the predetermined period, Based on the result of comparing the calculated value of the collected toner amount and the theoretical value, the calculated value of the replenished toner amount after the near-full state, the calculated value of the transfer toner amount after the near-full state, and, this performing a predetermined correction process is a process for correcting at least one calculated value of the collected toner amount after becoming the near full state An image forming apparatus comprising. The control unit is configured such that, as the calculated value of the collected toner amount for the predetermined period is smaller than the theoretical value, the calculated value of the collected toner amount after the near full state is not performing the correction process. As the calculated value of the collected toner amount for the predetermined period is larger than the theoretical value, the calculated value of the collected toner amount after the near-full state becomes smaller than when the correction process is not performed. as smaller, the image forming apparatus according to claim 1, characterized in that the correction process. When there is no toner in the developing device, toner is supplied from the container to the developing device until the toner amount in the developing device reaches a predetermined reference amount,
The control unit does not count the amount of toner replenished to the developing device from the state where there is no toner in the developing device until the amount of toner in the developing device reaches the reference amount as the replenished toner amount. the image forming apparatus according to claim 1 or 2, characterized in. The replenishing member includes a replenishing screw that replenishes toner in the container to the developing device by rotating,
A target value for the amount of toner to be replenished to the developing device when the replenishment screw makes one rotation is predetermined,
Wherein the control unit, the image forming apparatus according to any one of claims 1 to 3, characterized in that determining the replenishment toner amount by multiplying the target value to the rotation number of the supply screw. The control unit counts the number of dots on which toner is applied based on the image data, and calculates the transfer toner amount by multiplying the dot number by a predetermined toner consumption amount per dot. the image forming apparatus according to any one of claims 1-4.

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