JPH09197790A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the duplicated replacement of toner container by ending the alarm for urging the operator to replace a toner container which is judged as the replaced one before the end of a recovery operation. SOLUTION: In this device the outputs of a toner container sensor 143 and a door switch input 144 are used to judge that the toner container is already replaced when the toner container is detached once in a door open state under the toner near end or the toner end, and then is set. Also there is the probability that the operator, replaces the same toner container again when the operator can not judge that the toner container is already replaced, although the toner container is already replaced. Then, in the case of judging that the toner container is already replaced, it is displayed that the toner container is already replaced. This display is executed by turning off the LED display showing the toner end based on the recognition of the replacement of the toner container, Next, a color being at a replacement position is recovered.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, a facsimile and a printer, and more particularly, to a toner container that contains toner supplied to a developing device and is detachably mounted. The present invention relates to a provided image forming apparatus.

[0002]

2. Description of the Related Art Conventionally, as this type of image forming apparatus,
For example, by disposing a plurality of developing devices at a predetermined position on a rotating body provided in the vicinity of a photosensitive drum as a latent image carrier, and sequentially moving each developing device to a developing position facing the photosensitive drum. There is known a rotary developing device (hereinafter referred to as a revolver) that develops an electrostatic latent image on a photosensitive drum with toner of each color. For example, in a color image forming apparatus, in general, black and three complementary colors, that is, black,
Each of the developing devices has a developing device for adhering cyan, magenta, and yellow toner onto the photosensitive drum.

In recent years, in order to reduce the size of the apparatus, it is required to reduce the space of the developing device. The revolver described above is also one of the solutions, but in order to further save the space, the toner replenishing pipe that connects the toner container for accommodating the toner of each color and the developing device of each color is omitted, and the toner container A revolver in which the developing device and the developing device are arranged close to each other is considered. In such a revolver, each time the developing color is switched, the developing device for that color stops at a predetermined developing position, and thus the other developing devices also stop at predetermined positions. Further, toner is supplied from the toner container to the developing device through a toner supply port provided at both joints, but the direction of the toner supply port is the direction in which toner does not spill when the toner container is replaced. Since there is only one position facing toward, the toner container can be replaced with only one color when replenishing the toner.

[0004]

By the way, when the toner container becomes empty, it is replaced with a new toner container. Immediately after the replacement of the toner container, a toner concentration recovery operation for recovering the toner concentration in the developing device (hereinafter, a recovery operation) after the toner container is replaced so that an image can be formed with a stable toner concentration. Is being considered. In this operation, for example, in order to form an electrostatic latent image on the photosensitive drum, the density measuring pattern is created by sequentially turning on the QL (static elimination lamp), the charger, the developing bias, etc. according to the layout position. The density measurement pattern is read by an optical sensor for density detection, and the toner replenishment operation from the toner container to the developing device is repeated until the proper density condition is reached. It consists of a series of operations in which the photosensitive drum is stopped and terminated while sequentially turning off the bias, QL and the like. Note that, here, the operation from the rotation of the photosensitive drum to the creation of the density pattern is called pre-rotation processing, the density measurement pattern is created, and the toner is read until the density of the read pattern becomes an appropriate density condition. The operation of repeating the supply operation is called recovery processing. Further, the operation from the end of the toner replenishing operation to the stop of the photosensitive drum is called post-rotation processing. The above-mentioned pre-rotation processing and post-rotation processing are executed until the state on the photosensitive member is stabilized, so that some time is required.

Further, toner presence / absence detecting means for directly or indirectly detecting the presence / absence of toner in each toner container, and notifying means for urging the replacement of each toner container based on the output of the toner presence / absence detecting means. It is under consideration to provide a replacement and to prompt replacement of the empty toner container.

[Problem 1] If the notification by the notification means is ended after the recovery operation is completed, it takes some time from the replacement of the toner container to the completion of the recovery operation. There is a possibility that the toner container for the same developing device may be mistakenly replaced again during the recovery operation after replacing the container. In particular, if the operator who replaced the toner container leaves the front of the apparatus, another operator may replace the toner container again during the subsequent recovery operation. Such replacement of the duplicate toner container is a wasteful work. Further, there is a possibility that the toner existing at the joint between the toner container and the revolver body may be scattered inside and outside the apparatus.

[Problem 2] If the revolver is rotated without the toner container attached, the toner adhering to the toner container joining portion of the revolver body may be scattered into the apparatus. For example, in the case of a device having a device cover member that is opened and closed by an operator to replace the toner container, the revolver rotation is stopped for safety when the cover member is opened. Then, when the cover member is closed, the revolver rotation for homing processing for the purpose of recognizing the revolver rotation position or the recovery operation when the toner container is replaced while the cover member is opened. It has been considered to perform a revolver rotation for. If there is a toner container that is not attached when the revolver rotates after opening and closing the cover member, the toner is scattered.

[Problem 3] Mounting detection means for detecting the toner container mounted on the revolver main body is provided at a predetermined position in the moving path of the toner container accompanying the rotation of the revolver, and the toner container When the control that stops the revolver rotation for safety is adopted when the device cover member that the operator opens and closes for replacement is opened,
There is a possibility that the mounting detection means may make an erroneous detection. That is, when the device cover member is opened during rotation of the revolver and the revolver rotation is stopped for safety, whichever of the toner containers is installed even though all of the plurality of toner containers are installed. It occurs that the object is a revolver rotation position that does not exist in the above-mentioned predetermined position. When stopped at such a revolver rotation position, the attached toner container cannot be detected by the attachment detecting means. Therefore, it is erroneously detected that the toner container is not installed but the toner container is not installed. Therefore,
For example, if it is assumed that the mounting of the toner container is detected by the mounting detection unit as a precondition for the operation of the apparatus, the apparatus may remain stopped due to the erroneous detection.

[Problem 4] The erroneous detection of the mounting detecting means of the problem 3 is accompanied by the interruption of the power switch of the apparatus even when the revolver rotation stop control when the apparatus cover member is opened is not adopted. It can also occur when the revolver rotation stops.

[Problem 5] The recovery operation is executed when it is determined that the toner container has been replaced based on a predetermined criterion. Depending on this criterion, the toner container may actually be replaced. However, there is a risk that the recovery operation will be unnecessarily executed because it is determined that the replacement has been made by mistake even though it has not been replaced. That is, if a criterion for determining that the toner container is replaced when the toner cover is opened or closed when the operator opens and closes the device cover member that is opened and closed to replace the toner container is adopted, only the device cover member is opened and closed. Therefore, the recovery operation is executed even when the toner container is not actually replaced.

[Object 1] The present invention has been made in view of the above problems, and an object of the present invention is to prevent the toner container for the same developing device from being replaced by mistake due to duplication. An object of the present invention is to provide an image forming apparatus capable of performing the same.

[Purpose 2] Another object of the present invention is to provide an image forming apparatus capable of preventing the toner container moving means from being operated while the toner container is not mounted.

[Purpose 3] Another object of the present invention is to cover the device cover during the movement of the toner container by the mounting detector for detecting the toner container at a predetermined position in the moving path of the toner container by the toner container moving means. An object of the present invention is to provide an image forming apparatus capable of preventing a defect due to erroneous detection caused by opening a member and stopping movement.

[Purpose 4] Another object is to attach the power supply to the apparatus while the toner container is being moved by the attachment detecting means for detecting the toner container at a predetermined position in the moving path of the toner container by the toner container moving means. An object of the present invention is to provide an image forming apparatus capable of preventing a malfunction due to an erroneous detection caused by the switch being cut off and the movement being stopped.

[Object 5] Another object of the present invention is to provide an image forming apparatus capable of accurately determining replacement of a toner container.

[0016]

In order to achieve the above-mentioned object, the invention of claim 1 is provided with a plurality of toner accommodating containers for accommodating toner to be replenished in a developing device and being detachably mounted. In an image forming apparatus, a toner presence / absence detecting unit for directly or indirectly detecting the presence / absence of toner in each toner container, and an informing unit for urging replacement of each toner container based on the output of the toner presence / absence detecting unit. And a judgment means for judging whether or not the toner container has been replaced based on a predetermined judgment standard, and a toner in the developing device when the judgment means judges that the toner container has been replaced. Recovery control means for performing a predetermined recovery operation for replenishment, each time it is determined that the replacement operation has been performed based on the determination result of the determination means, it is determined that the replacement operation is performed without waiting for the completion of the recovery operation And it is characterized in that provided the notification control means to terminate the notification of the notification unit for the toner container.

According to a second aspect of the present invention, there is provided a joint between a toner container that accommodates the toner to be replenished in the developing device and is detachably mounted, and a toner discharge port of the toner container. In the image forming apparatus including a moving unit that moves the toner container while holding the toner container, a mounting detection unit that detects whether or not the toner container is mounted, and the toner based on the output of the mounting detection unit. A movement prohibition control means for prohibiting the operation of the movement means when the container is not attached is provided.

According to a third aspect of the present invention, a joint portion between a plurality of toner containers that contain toner to be replenished in the developing device and is detachably mounted, and a toner discharge port of the toner container. In the image forming apparatus having a moving unit that moves the toner container while holding the toner container, whether the toner container is attached or not at a predetermined position on the moving path of the toner container by the moving unit. Mounting detection means for detecting, cover detection means for detecting opening / closing of a device cover member opened / closed by an operator at the time of replacement of the toner container, and movement of the toner container of the toner container based on an output of the cover detection means. A movement stop control means for stopping movement by the movement means when the cover member is opened during movement drive, and movement stop during the movement by the movement stop control means When it is detected that the cover member is closed based on the output of the storage means and the output of the cover detection means, in the state of being stopped during the movement based on the stored content of the storage means. When it is judged that the cover member is closed, the output of the mounting detecting means at the toner container moving position is ignored when it is detected that the cover member is closed.

Further, according to a fourth aspect of the present invention, a joint portion between a plurality of toner containers that contain the toner to be replenished in the developing device and is detachably mounted, and a toner discharge port of the toner container. In the image forming apparatus having a moving unit that moves the toner container while holding the toner container, whether the toner container is attached or not at a predetermined position on the moving path of the toner container by the moving unit. When the device power switch is cut off during the movement by the mounting detecting means and the moving means, the fact that the device was moving at the time of the cutoff is stored, and at least until the device power switch is turned on thereafter. When the storage means capable of holding the stored contents and the device power switch are turned on, it is determined that the device power switch is cut off during the movement based on the stored contents of the storage means. When you are those characterized by ignoring the output of the installation detection means while said toner container movement position of the condition.

Further, according to a fifth aspect of the present invention, in an image forming apparatus having a toner container that accommodates toner to be replenished in a developing device and is detachably mounted, it is determined whether or not the toner container is mounted. It is characterized in that mounting means for detecting and a replacement judging means for judging that the toner container has been replaced based on a change in the presence or absence of the toner container based on an output of the mounting detection means are provided. .

According to the first aspect of the invention, each time the judgment means for judging whether or not the toner container has been replaced determines that the toner container has been replaced, a predetermined amount for replenishing the toner in the developing device is determined. The notification of the toner container determined to be replaced is ended by the notification means for urging the replacement of the toner container without waiting for the completion of the recovery operation.

According to the second aspect of the invention, the toner container is moved while being held when the toner container is not mounted, based on the output of the mounting detection means for detecting the presence / absence of mounting of the toner container. The operation of transportation means is prohibited.

According to the third aspect of the present invention, the attachment detecting means detects whether or not the toner container is attached at a predetermined position on the moving path of the toner container by the moving means. Further, the cover detection means detects the opening / closing of the device cover member opened / closed by the operator when the toner container is replaced. Then, based on the output of the cover detection means, when it is detected that the cover member is opened during the movement drive of the toner container by the moving means that moves the toner container while holding it, the movement is stopped. The control means stops the movement by the moving means. Further, the storage means stores that the movement is stopped during the movement by the movement stop control means. Then, when it is detected that the cover member is closed based on the output of the cover detection means, when it is determined that the cover member is stopped during the movement based on the stored contents of the storage means, the cover is closed. The output of the mounting detection means at the toner container moving position at the time of detecting that the member is closed is ignored.

According to the fourth aspect of the present invention, the mounting detecting means detects whether or not the toner container is mounted at a predetermined position on the moving path of the toner container by the moving means. When the device power switch is shut off while the toner container is being moved and driven by the moving means for moving the toner container while holding it, the storage means indicates that the toner container was moving during the shutoff. The stored contents are stored, and the stored contents are held at least until the device power switch is turned on thereafter. When the device power switch is turned on and it is determined that the device power switch is shut off during the movement based on the stored contents of the storage unit, the toner container moving position in the state is maintained. The output of the mounting detection means is ignored.

According to the fifth aspect of the present invention, the mounting detecting means detects whether or not the toner container, which accommodates the toner supplied to the developing device and is detachably mounted, is mounted. Then, the replacement determining means determines whether or not the toner container has been replaced based on a change in the presence or absence of the toner container based on the output of the mounting detecting means. (Hereinafter, margin)

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment in which the present invention is applied to a color electrophotographic printer (hereinafter referred to as a printer) which is an image forming apparatus will be described below.

First, the basic configuration of the printer according to this embodiment will be described. FIG. 1 is a block diagram showing the basic configuration of the printer according to this embodiment. The printer 10 shown in FIG. 1 supplies a printer unit 1 that forms a color image by an electrophotographic process, a scanner unit 2 that transfers image data read from a document to the printer unit 1, and a transfer sheet to the printer unit 1. Bank unit 3 which is the supply device of
And a DF unit 4 which is a document feeding device for feeding a document to the scanner unit 2 and a sorter unit 5 which is a post-processing device for sorting transfer sheets discharged from the printer unit 1. There is. The basic configuration of the entire printer is almost the same as that of a conventional printer of the same type.

FIG. 2 is a block diagram showing the configuration of the control system of the printer 10 described above. In FIG. 2, a printer controller 100, a scanner controller 200, and a bank controller 3
00, DF control unit 400, and sorter control unit 500 correspond to the respective units shown in FIG.

The printer control unit 100 is a part for controlling the electrophotographic process sequence and the paper carrying process.
The printer control unit 100 is connected to the bank control unit 300 and the sorter control unit 500 by optical fiber serial communication, and performs control according to image forming timing by a predetermined command. The scanner control unit 200 is
This is a part that controls reading of image data of a document and image processing control. This scanner control unit 200 uses the DF
It is connected to the control unit 400 by optical fiber serial communication, and controls the document supply sequence by a predetermined command. The system control unit 800 is a unit that controls the entire system of the printer 10, and the operation control unit 900.
An image input condition is passed to the printer control unit 100 and the scanner control unit 200 according to an instruction input from the device, the state of the entire system is managed and controlled, and a display command is issued. The system control unit 800 is connected to each control unit by optical fiber serial communication. Operation control unit 900
Receives an instruction from the user, passes it to the system control unit 800, and displays the system status, messages, and the like in accordance with a display command from the system control unit 800.

Further, since the printer control unit 100 and the scanner control unit 200 are required to have strict accuracy in position alignment at the time of image superposition and in registration of the transfer sheet and the image, direct sequence control is required. It is connected by optical fiber serial communication. Further, a data bus for directly transferring image data from the scanner control unit 200 to the printer control unit 100 is also provided.

FIG. 3 is a block diagram showing a detailed circuit configuration of the printer control unit 100 described above. The functions of the printer control unit 100 are CPU (Central Processing Unit) 101, R
It is realized by the OM 102, the RAM 103, the serial communication controller 104, the write control IC 105, the I / O controller 107, and each sensor. Less than,
Each unit will be described in order centering on the CPU 101.

The CPU 101 is a circuit for calculating and executing program contents, and controls the entire printer controller 100. The CPU 101 controls the recovery operation according to the flowchart described later. RO
M102 is a memory including a control program, RAM1
A memory 03 stores and saves data. C
The PU 101 and each memory are connected by a data bus and an address bus. Serial communication controller 1
Reference numeral 04 denotes each control unit (scanner control unit 20 shown in FIG.
0, the bank control unit 300, the sorter control unit 500, and the system control unit 800), and is a circuit that transmits and receives commands, and is connected to the CPU 101 by a data bus and an address bus. The writing control IC 105 is a circuit that controls exposure of image data, and controls the LD control unit for exposure and the polygon motor 115. The write control IC 105 is connected to the CPU 101 via a data bus and an address bus. I
The I / O controller 107 sends CP from each section in the printer.
Input / output control is performed to the U 101 and from the CPU 101 to each unit.

The fixing unit (Fuser) 160 performs PWM output for controlling the fixing heater based on the input value of a fixing thermistor A / D (not shown). The power pack unit (PowerPack) 170 controls the output of the power pack by PWM based on the input value of the feedback A / D from the power pack (not shown).
The output of the power pack unit 170 includes a charging charger, a charging grid, a developing bias, and a developing D which will be described later.
It has outputs of a C bias, a developing AC bias, a belt transfer charger, and a paper transfer charger. An electrometer circuit (V-Sensor) 180 is a sensor that measures the surface potential of the photosensitive drum, which will be described later, and the output is the CPU 1.
01 A / D input. Optical sensor circuit 1
Reference numeral 81 denotes a circuit of an optical sensor, which will be described later, for measuring the amount of toner adhered to the photosensitive drum. The phototransistor output of this optical sensor is the A / D input of the CPU 101, and the PWM output from the CPU 101 is the LED of the optical sensor. Connected to the drive circuit.

The main motor 110 is a motor for driving the paper carrying system, and the drum motor 111 is a motor for driving the photosensitive drum and the intermediate transfer belt. The developing motor 112 is a motor for driving a developing sleeve described later. The CPU 101 outputs an ON signal and a half-speed signal for reducing the speed to half to each motor, and the rotation speed (speed) of the motor reaches the target rotation speed from each motor to the CPU 101. A steady motor rotation signal (Lok) for determining is input. The revolver motor 113 is a motor for rotating a revolver including a developing device described later. The revolver motor 113 is supplied with a four-phase output from the CPU 101, and performs control for stopping the designated development color at the development position. The replenishment motor 114 is a motor for replenishing the developing unit with toner from a toner container (not shown), and controls the on-time according to the toner adhesion amount.

The intermediate transfer belt mark sensor 150 is a sensor for detecting a reference mark which serves as a reference for alignment during color superposition. The signal from this sensor is connected to the interrupt input (Int) of the CPU 101 because it requires strict accuracy in terms of timing. The revolver home position sensor 151 is a revolver home position (hereinafter, revolver HP) that serves as a reference for the stop position of the revolver.
Is a sensor that detects The signal from this sensor is required to have strict timing accuracy of switching output pulses during rotation of the revolver.
Is connected to the interrupt input (Int).

FIG. 4 shows the I / O controller 10 described above.
7 is a block diagram showing a connection between the computer 7 and peripheral devices. FIG. Outputs from the I / O controller 107 include a registration clutch (CL) 130, a manual feed CL 131, a manual feed pickup solenoid 132, a discharge lamp 133, an intermediate transfer belt cleaning contact / separation solenoid 134, and a lubricant application solenoid 135. Further, as inputs, there are a registration sensor 140, a manual paper end sensor 141, a paper discharge sensor 142, a toner container sensor 143, a door switch input 144 for detecting an open / closed state of a door provided in the printer body, and the like.

FIG. 5 is a schematic configuration diagram showing a main part of the printer unit 1 shown in FIG. Printer unit 1 shown in FIG.
Is roughly divided into a photosensitive drum 1 as a latent image carrier.
1. Revolver 20 as developing device, intermediate transfer belt 3
0, a writing system unit 40 as a laser optical device.

Around the photosensitive drum 11, a charge eliminating lamp (hereinafter, QL) 18 for erasing the residual charge on the photosensitive drum 11, a charging charger (hereinafter, charging CH) 12 as a charging means, a photosensitive member. An electrometer 13 for measuring the surface potential of the drum 11, an optical sensor 14 for reading the image density on the photoconductor drum 11, a photoconductor drum 1 before transfer.
A pre-transfer charge erasing lamp (hereinafter, PTL) 15 for lowering the surface potential of No. 1, a belt transfer charger 16 for giving + charge, and a drum cleaning device 17 for removing toner remaining on the photosensitive drum 11 are provided. It is arranged. The photosensitive drum 11 and the intermediate transfer belt 30 are
Both are rotationally driven by the drum motor 111 shown in FIG.

Revolver 2 in contact with the photosensitive drum 11
The inside of 0 is divided into four, and developing devices 21K, C, M, and Y of four colors of yellow (Y), magenta (M), cyan (C), and black (K) are provided. . Cylindrical developing sleeves 22K, C, M, and Y as a developer carrying member are rotatably supported on the developing devices 21K, C, M, and Y, respectively. The developing sleeve 22 is rotationally driven by the developing motor 112 shown in FIG. Further, a toner container (not shown) as a toner container that contains toner corresponding to each color is detachably held in each of the developing devices 21K, C, M, and Y. This toner container is arranged close to the developing devices 21K, C, M and Y, and moves in conjunction with the developing devices 21K, C, M and Y. The developing position of the revolver 20 is located between the potential sensor 13 on the photoconductor drum 11 and the optical sensor 14. In FIG. 5, the developing device 21K is in the developing position. The revolver 20 is rotationally driven in the direction of arrow C by the revolver motor 113 shown in FIG. The CPU 101 shown in FIG. 3 is a revolver motor 1 with four-phase output.
13 is rotationally controlled to stop the development color of the designated color at the development position. The HP that serves as the stop position reference of the revolver 20 is
Revolver HP sensor 1 disposed below the revolver 20
Detected by 51.

The writing system unit 40 includes a polygon mirror 116 rotated by a polygon motor 115, and fθ.
It is composed of optical components such as a lens 117 and a mirror 118. The laser beam generated by an LD (laser diode) (not shown) is reflected by the polygon mirror 116.
It is rotated and scanned by the lens, the optical path is bent by the mirror 118 through the fθ lens 117, and it is exposed between the charge CH12 and the electrometer 13 on the photosensitive drum 11 uniformly charged by the charge CH12.

On the other hand, a belt mark sensor 15 which is provided inside the belt around the intermediate transfer belt 30 and which reads a mark (not shown) which serves as a reference for alignment during color superposition.
0, a lubricant application unit 32 for applying a lubricant on the intermediate transfer belt 30, a paper transfer charger 33 for transferring an image transferred on the intermediate transfer belt 30 to a transfer paper (not shown), an intermediate transfer belt 30 A belt cleaning unit 34 is provided for cleaning the untransferred toner and the residual toner. The intermediate transfer belt 30 and the photosensitive drum 11 are connected to the belt transfer charger 1 during image formation.
6 are in contact with each other, but two support rollers 119,
By moving 120, the intermediate transfer belt 30 can be separated from the photosensitive drum 11 as shown by the broken line in the figure. The peripheral length of the intermediate transfer belt 30 is set to be longer than the sum of the maximum image size and the pattern area of the optical sensor (including the distance from the image rear end and the pattern margin length). Further, the belt cleaning unit 34 is configured to be able to come into contact with and separate from the intermediate transfer belt 30 by an intermediate transfer belt cleaning solenoid (not shown). Further, the application of the lubricant is configured so that it can be brought into contact with and separated from the intermediate transfer belt 30 by a lubricant application solenoid (not shown), and it is possible to apply or not apply the application.

Further, upstream of the paper transfer charger 33,
A registration roller 50 and a registration sensor 140 are provided, and a transport belt 51 and a fixing unit (not shown) are provided downstream. Of these, the registration roller 50, the conveyor belt 51, and the fixing roller (not shown) are rotationally driven by the main motor 110 shown in FIG. Further, the registration roller 50 is turned on / off by the registration clutch 130 shown in FIG.

In the structure of FIG. 5 described above, the photosensitive drum 11 is charged in the charging CH1 while being rotationally driven in the direction of arrow A.
After being uniformly charged by 2, the writing system unit 40
Thus, scanning exposure is performed based on the image information, and an electrostatic latent image is formed on the surface. Here, the image information to be exposed is black image information if it is a single color, and if it is full color,
Select the desired full-color image from yellow, magenta, cyan,
And image information of a single color decomposed into black color information. Further, the electrostatic latent image formed on the photoconductor drum 11 is developed by the revolver 20 with yellow, magenta, cyan, and black toners as predetermined developers, respectively, so that each color image on the photoconductor drum 11 is developed. Is formed.

On the other hand, the respective color images formed on the photoconductor drum 11 are formed in yellow, magenta, cyan and black on the intermediate transfer belt 30 which rotates in the direction of arrow B in the figure in synchronization with the photoconductor drum 11. The belt transfer charger 16 sequentially and sequentially transfers each color. Yellow, magenta, cyan, superimposed on the intermediate transfer belt 30
The black image and the black image are collectively transferred by a paper transfer charger 33 onto a transfer paper (not shown) conveyed from a paper feed tray (not shown) through a paper feed roller (not shown) and a registration roller 50. After completion of the transfer, the transfer paper is sent to a fixing roller (not shown) by the transport belt 51, where the toner image is fixed and discharged outside the apparatus as a full-color print.

The toner on the photosensitive drum 11 that has not been transferred onto the intermediate transfer belt 30 is removed from the photosensitive drum 11 by the drum cleaning device 17, and is not transferred onto the transfer paper (not shown). The toner on the transfer belt 30 is removed by the belt cleaning unit 34.
Is removed from the intermediate transfer belt 30.

Next, the sequence of image formation will be described with reference to the timing charts of FIGS. 6 to 8 and a block diagram. In each timing chart described below, it is assumed that any one of the developing devices is at the developing position. Further, “FGATE” in the timing chart is a gate signal of image data, and the image data is written on the photosensitive drum 11 while it is on. Furthermore, in the following description, corresponding items in the timing chart are shown in parentheses. First, a sequence in the case of forming a monochromatic image will be described with reference to the timing chart of FIG. 6 and each block diagram. FIG. 6 shows an example in which two black and white images of A4 size (conveying paper in the short side direction) are output.

When the start instruction (a) arrives from the system control unit 800, the CPU 101 (FIG. 3) turns on the QL 18 and the drum motor 111 (g, b). Then, when the start position (charge-removed portion) on the photosensitive drum 11 reaches the charging position, the charging CH 12 is turned on (h). Further, when the charged portion on the photosensitive drum 11 reaches the developing position, the developing biases DC and AC and the developing motor 112 are turned on (i, j, k). Further, when the position where the developing bias on the photoconductor drum 11 is turned on reaches the belt transfer position, the belt transfer charger 16 is turned on (n). This is the front rotation. When the development color of the developing device at the development position when the revolver 20 is stopped is different from the designated development color, the development bias DC,
After the AC is turned on, the revolver 20 is rotated until the designated development color reaches the development position. In this case, up to this point is the pre-rotation.

If the exposure position on the photosensitive drum 11 is charged by the pre-rotation, the photosensitive drum 1
A latent image can be formed on 1. CPU 101
The scanner controller 200 (FIG. 3) is instructed to turn on the lamp and start the scanner so as to send the image data after the timing (d). When the image is scanned, the image data is transferred from the scan control unit 200 to the write control IC 105 (FIG. 3). Write control I
At C105, the image data is exchanged with the exposure data, and the LD control unit 106 and the polygon motor 115 are controlled to perform exposure so as to form an electrostatic latent image on the photosensitive drum 11 (e).

The electrostatic latent image formed on the photosensitive drum 11 is developed by the developing device 21, and the belt transfer charger 1
The image is transferred to the intermediate transfer belt 30 by 6. And C
The PU 101 turns on the paper transfer charger 33 before the transferred image reaches the paper transfer position (o), and transfers the image to the transfer paper. The transfer paper is fed in time for the paper transfer timing, and the registration roller 50
After the front end of the transfer paper is abutted against (FIG. 5) to enter the standby state, the registration clutch 130 (FIG. 4) is turned on (r) at the timing when the front end of the image and the front end of the transfer paper match at the paper transfer position. Further, the transfer sheet on which the image has been transferred is conveyed to a fixing unit (not shown) by the conveyor belt 51 (FIG. 5), heat-fixed by a fixing roller and discharged to a sheet discharge tray (not shown).

When the CPU 101 determines that there is no next image formation after the paper transfer is completed, the CPU 101 proceeds to the end sequence. Here, first, the belt transfer charger 16 is turned off (n), and when the position on the photosensitive belt 11 where the belt transfer charger 16 is turned off reaches the position of the charging CH12, the charging CH12 is turned off (h). Next, when the position reaches the developing position, the developing bias DC, AC
And the developing motor 112 is turned off (i, j, k). From this point, the mark sensor 150 (FIG. 5) is set in the reference mark detection standby state (c), and after the mark detection, the drum motor 111 is turned on until the reference mark is stopped at a predetermined position (b), and the drum motor 111 is turned on. QL at the same time of turning off
Turn off 18 (g).

The CPU 101 uses the photosensitive drum 11
After performing the upward exposure, the optical sensor 14 and the optical sensor LED (not shown) are turned on (f, l). Further, the PTL 15 is turned on before turning on the paper transfer charger 33 (m). However, the belt cleaning unit 34 maintains the contact state (p), and the revolver motor 113 (FIG. 3).
Is not turned on because it is a single color (q).

Next, a sequence for forming a full-color image will be described with reference to the timing chart of FIG. 7 and each block diagram. However, the description of the same parts as those in FIG. 6 will be omitted. FIG. 7 shows a timing chart in the case of outputting one full-color image of A4 size (paper conveyance in the short side direction). (Hereinafter, margin)

The control up to the pre-rotation is the same as the sequence for single color shown in FIG. 6, but in the full-color sequence, the colors are switched during image formation. That is, when the drum motor 111 is turned on, the intermediate transfer belt 3
When 0 rotates and the mark sensor 150 detects the reference mark (c), since the mark sensor 150 is connected to the interrupt terminal of the CPU 101, the interrupt process is executed on the program of the CPU 101. Among them, the scan start command for the first color (K) is issued to the scanner control unit 200.
To (d). Then, after developing the electrostatic latent image of the first color (K) on the photosensitive drum 11 by the developing device 21K,
When the transfer to the intermediate transfer belt 30 is completed, the revolver 20 is connected so that the developing device 21C for the second color (C) reaches the developing position (q). In addition, the intermediate transfer belt 3
When the transfer to 0 is completed, the intermediate transfer belt 30
The belt cleaning unit 34 that has been in contact with is released (p) so that the image on the intermediate transfer belt 30 is not erased.

After that, when the mark sensor 150 detects the reference mark again (c), a scan start command for the second color (C) is transmitted to the scanner controller 200 (d). After the electrostatic latent image of the second color (C) is developed by the developing device 21C, when the transfer to the intermediate transfer belt 30 is completed, the revolver is moved so that the developing device 21M of the third color (M) reaches the developing position. Rotate 20 (q). Below, the third color (M),
The fourth color (Y) is similarly developed and the image is superimposed on the intermediate transfer belt 30. The full-color image transferred to the intermediate transfer belt 30 in this way turns on the paper transfer charger 33 (o) immediately before reaching the paper transfer position in order to transfer the image onto the transfer paper, and transfers the image to the transfer paper. The transfer paper is transported in the same way as in the case of a single color.

Now, the intermediate transfer belt 30 for the fourth color (Y)
Upon completion of the transfer to (1), the revolver 20 is rotated (q) so that the developing device 21K for the first color (K) is set at the developing position to prepare for the next image formation. At the same time, the belt cleaning unit 34 is changed from the released state to the contact state,
The transfer residual toner after the paper transfer on the intermediate transfer belt 30 is cleaned to prepare for the next image formation (p). Note that the ending sequence is the same as that for a single color.

FIG. 8 shows A3 size (paper is conveyed in the long side direction)
7 is a timing chart when one full-color image is output. In FIG. 7, the image forming cycle for one color is one revolution of the intermediate transfer belt 30, but in FIG. 8, the image forming period for one color is two revolutions. This is because in the A3 size, there is no timing to switch to the next development color in one round of the intermediate transfer belt 30, and therefore the reference mark detection of the mark sensor 150 is skipped once for each color. Also,
The timing of the contact of the belt cleaning unit 34 and the timing of paper transfer are different between A4 and A3. However, in the case of A4, the entire image is inserted from the position of the belt transfer charger 16 to the position of the paper transfer charger 33. The belt cleaning unit 34 is contacted at an earlier timing. However, in A3, the contact is made after the paper is transferred, in order not to be entirely within the interval and in order to avoid the transfer failure due to the vibration of the contact during the transfer of the paper.

When outputting an image captured from the outside, without instructing the scanner control unit 200 to start the scanner, the image data is output at the reference mark detection timing of the mark sensor 150 even when the colors are overlapped. By writing, a desired transfer paper output can be obtained.

Next, the revolver 20 in the present embodiment.
The configuration of the toner container will be described. 9 is a conceptual cross-sectional view showing the internal structure of the revolver 20, and FIG.
FIG. 4 is a conceptual cross-sectional view showing a toner circulation path in the revolver 20. 9 is a sectional view when the front side plate 600 of FIG. 10 is removed and seen from the axial direction.
The elements in front of are shown. In addition, FIG.
Although a conceptual sectional view of an arbitrary developing device is shown, here,
The vertical conveying screw 606 of the developing device 21K shown in FIG.
612 shows a vertical cross-sectional view taken along a plane including the central axis of 612.

In FIG. 9, the revolver 20 includes a substantially disk-shaped front side plate 600 and a rear side plate 601 (see FIG. 10), and a developing casing portion 602. The inside of the developing casing portion 602 includes partition portions 602-1, 602-2,
It is divided into four parts by 602-3, 602-4, and each partition part has a developing device 21K corresponding to K, C, M, Y.
C, M and Y are arranged respectively. In the example of FIG.
At the developing position facing the photoconductor drum 11 is a black developing device 21K containing black toner and a carrier,
In the following, in the order of clockwise rotation in the drawing, a cyan developing device 21C containing cyan toner and carrier, a magenta developing device 21M containing magenta toner and carrier, and a yellow developing device 21Y containing yellow toner and carrier.
Are arranged.

Since the internal structures of the four developing units are exactly the same, the internal structure will be described below on behalf of the black developing unit 21K at the developing position in FIG. Developing device 21K
Is a small unit consisting of a cylindrical developing sleeve 22K and a doctor 603 provided between two small side plates 604 (one of which is omitted in FIG. 9) arranged to face each other on the front side and the other side in the figure. 605K, an upper conveying screw 606, a paddle 607, a lower conveying screw 612, and the like. A shaft 608 is arranged below the small unit 605K so as to pass through the two small side plates 604. This axis 60
8 is further supported by a front side plate 600 and a rear side plate 601, and the entire small unit 605K is configured to be rotatable about a shaft 608 as a fulcrum. Further, elongated holes 609 are formed at the upper ends of the two small side plates 604, and they are respectively fixed to the front side plate 600 and the rear side plate 601 by screws (not shown). According to this, by loosening the screw and rotating the small unit 605K around the shaft 608, the developing sleeve 22K is moved to the photosensitive drum 1.
Since it can be moved closer to or farther from 1, the developing gap between the developing sleeve 22K and the photoconductor drum 11 can be adjusted.

During development, as shown in FIG. 9, the revolver 20 is stopped so that the center of rotation of the developing sleeve 22 (22K in this case) is located horizontally from the center point 611 of the photosensitive drum 11. Is set. This position is called a developing position, and is a regular stop position of the revolver 20.

FIG. 11 is a conceptual side view showing the mounted state of the toner container, and FIG. 12 is a front view showing the internal structure of the toner container and the toner hopper. In addition, FIG.
FIG. 12 shows a state in which the revolver 20 is viewed from the side opposite to FIG. 10, and FIG.
The state when viewed from above is shown.

As shown in FIG. 11, the front side plate 600, the rear side plate 601 and the developing devices 21K, C, M and Y (in the figure,
(Only K and Y are shown) constitutes a cylindrical revolver 20 as a whole. Further, toner containers 621 to 624 for accommodating toners of respective colors K, C, M, and Y are arranged at the forefront portion (the left end portion in the drawing) of the revolver 20 (in the drawing, Only K and Y are shown). The toner containers 621 to 624 are arranged in the developing unit 21K shown in FIG.
It corresponds to the arrangement of C, M and Y. That is, as shown in FIG. 12, the toner of K is in the toner container 621 (omitted in the drawing), and the toner of C is in the toner container 622, M.
The toner is stored in the toner container 623, and the toner of Y is stored in the toner container 624.

As shown in FIG. 10, a toner hopper 610 is arranged at the frontmost part of the revolver 20 in proximity to the toner containers 621 to 624. Here, since the structure of the toner hopper 610 is the same for all four colors, the upper conveying screw 606 and the lower conveying screw 612 have the same reference numerals. As shown in FIG. 12, toner container 621-6
24 and the toner hopper 610 are assembled in a state in which the substantially concave portion of the toner container and the substantially convex portion of the toner hopper are fitted together. In this way, in the state where the toner container and the toner hopper are assembled, the frontmost part of the revolver 20 is shaped like a cylinder or a part of a cylinder as a whole.
Each toner hopper 610 constitutes a unit in a state of being fixed to a disc-shaped side plate (not shown), and is connected to the revolver 20 by a pipe-shaped guide 640 covering the lower conveying screw 612 as shown in FIG. ing. In FIG. 12, reference numeral 617 is a toner container 621.
8A to 8D show communication paths when toner is replenished into the toner hopper 610.

In FIG. 12, the toner container (621) (not shown) in the developing position is in the first quadrant, and the toner container 623, which will be described later, is in the third quadrant. Below the toner container 623 located in the third quadrant, a toner container sensor 143 for detecting the presence or absence of the cartridge at the replacement position is provided. The toner container sensor 143 is a reflection type photo sensor. When the toner container is in the third quadrant, the toner container sensor 143 detects the reflection and notifies the CPU 101 of FIG. 3 that the toner container is present. When it is not in the third quadrant, no reflection is detected, so the absence of a toner container is notified.

Next, the replenishment of toner from the toner container to the toner hopper will be described. FIG. 13 is an explanatory diagram showing how toner is moved from the toner container to the toner hopper, and corresponds to FIG. Here, since the toner in each of the toner containers 621 to 624 moves in the same manner, the black toner container 621 will be described as a representative. As shown in FIG. 13, when the toner container 621 for black is in the developing position, the toner container 621 and the toner hopper 61 are
The communication passage 617 formed commonly at the joint with 0 is oriented in a substantially vertical direction as indicated by an arrow 616. Further, since the side wall portion of the toner container 621 toward the communication passage 617 is formed in a funnel shape, the toner container 621 is formed.
The toner contained therein moves to the toner hopper 610 side by the action of gravity and is filled in the toner hopper 610. When the other toner container is set at the developing position, the toner is similarly moved to the corresponding toner hopper and filled. The inner wall contact surface of the toner container 621 with which the toner comes in contact is formed by the communication passage 6
Since it is connected to 17 with a smooth surface 618,
In addition to the action of gravity when the communication passage 617 is oriented in the vertical direction, the shape of the cartridge guides the toner to the entrance of the communication passage 617 by the rotation of the revolver 20, so that the toner stored in the toner container does not remain. Can be used up.

Next, the conveyance of toner from the toner hopper to the developing sleeve will be described. Since the toner is conveyed from each toner hopper to the developing sleeve by the same operation, the black developing device 21K will be described here as a representative. As shown in FIG. 10, a replenishing roller 613 is disposed below each toner hopper 610. The toner accumulated on the replenishing roller 613 passes through a plurality of toner discharge ports 626 formed in the lower part of the hopper according to the rotation of the replenishing roller 613, and then onto the lower conveying screw 612 extending to the lower part of the hopper. To fall. These toners are transported in the direction of the arrow in the figure as the lower transport screw 612 rotates. Then, it is discharged to the outside of the paddle 607 through an opening 627 formed in the paddle 607, and vertical stirring is performed by the paddle 607. The vertically stirred toner is pumped up to the developing sleeve 22K (see FIG. 9) and is used for development.

On the other hand, as shown in FIG. 9, during development, the photosensitive drum 11 is rotated counterclockwise and the developing sleeve 2 is rotated.
Each 2K rotates clockwise. Doctor 603
It is in contact with the developing sleeve 22K, and the developing sleeve 22K
The amount of toner carried on the paper is regulated. Further, in FIG. 9, reference numeral 614 indicates a screw guide that covers the upper conveying screw 606. A part of the surplus toner regulated by the doctor 603 is stored in the screw guide 6
14 and is conveyed to the front side of the drawing by the upper conveying screw 606. Then, as shown in FIG. 10, the toner carried by the upper carrying screw 606 is sent onto the lower carrying screw 612 through the toner discharge pipe 615 provided in the front, and passes through the toner hopper from the above-mentioned toner container. Mixed with replenished toner. In this way, the uneven density of the toner is eliminated by the horizontal stirring by the two screws 606 and 612 arranged vertically and the vertical stirring by the paddle 607.

The revolver 20 is provided with four developing units for circulating the toner every 90 degrees, whereby the revolver 20 having a four-color structure is constructed. When developing a color image, the revolver 20 rotates counterclockwise to switch colors in the order of K → C → M → Y. By the rotation of the revolver 20, the toner is loosened in the toner container, and the rotation direction is taken into consideration so that the toner is accumulated on the supply roller 613 shown in FIG.

Also, the revolver 20 according to this embodiment.
In the replacement position of the toner container, the replenishment port (not shown) of the toner container faces upward so that the toner does not scatter inside and outside the apparatus even if there is residual toner in the toner container. Limited to quadrant position. For example, in FIG. 12, since the toner container 623 is in the third quadrant, only the toner container 623 can be replaced at this position. The limitation of the exchange position is restricted by the inner cover 630 shown only by the outer edge in FIG. That is, the inner cover 630 has a notch formed only at the position of the toner container in the third quadrant, and the toner container cannot be taken out at any position other than this notch. The position in the third quadrant is called the exchange position with respect to the developing position.

FIG. 14 is a diagram in which a color at the current developing position is associated with a target moving color to be moved to the developing position. For example, if a black (K) toner container is present at the developing position, cyan (C) may be rotated 90 degrees to move to the developing position, and magenta (M) may be rotated 180 degrees. It will be good. FIG. 15 is a diagram in which the developing position color and the replacement position color are associated with each other. For example, if the developing position color is (M), then the replacement position color is (K). As described with reference to FIG. 5, the HP serving as the stop position reference of the revolver 20 is detected by the revolver HP sensor 151 disposed below the revolver 20. The CPU 101 (FIG. 3) causes the revolver HP sensor 151 to detect the HP of the revolver, thereby (K).
The developing device can be stopped at the developing position. Also,
By referring to the correspondence tables shown in FIGS. 14 and 15,
It is possible to know how much the target moving color should be rotated in order to move it to the developing position, or from the current developing position color, the exchange position color at that time.

By the way, in the printer according to this embodiment, a reference density pattern is formed on the photosensitive drum every time a predetermined number (for example, 10) of printing operations are performed, and the image density of this pattern is measured by the optical sensor ( 5) is read and toner is supplied to the developing device according to the value, so that the toner concentration of the toner in the developing device is controlled to a predetermined concentration. In such toner concentration control, when it is determined that the toner concentration of the toner in the developing device is continuously low a predetermined number of times (for example, 3 times), it is determined that the developing device is in the toner near end state, A toner near-end LED (not shown) corresponding to this developing device is turned on. After the toner near-end LED is turned on, a predetermined number of printing operations by the developing device are permitted. After that, it is determined that the developing device is in the toner end state, and the toner (not shown) corresponding to the developing device is determined. The end LED is lit. After the toner end LED lights up, for example, without permitting the printing operation,
It waits until the user replaces the toner container, or executes other preparation operations. When there is a toner container near the toner end or a toner container that is in the toner end at the time when the print operation is normally completed, and when the last print operation of the predetermined number of print operations in the toner end state is completed. In order to facilitate the operator's replacement of the toner container, the toner near-end or toner-end toner container is moved to the replacement position by the revolver rotation drive, and then put in the standby state. Also for this revolver rotation drive, by referring to the correspondence tables shown in FIG. 14 and FIG.
The predetermined toner container is moved to the replacement position. The toner container is replaced for a reason other than the toner end or the toner near end, but here, the toner container is replaced by the toner end or the toner near end.

The front cover (hereinafter referred to as a door) of the printer main body is opened by the user with respect to the printer in the standby state with at least one toner container near the toner end or the toner end being present. When the toner container is removed from the replacement position, a new toner container is attached to the predetermined developing device from the replacement position, and the door is closed, the toner container replacement work is completed. After this work, a recovery operation for restoring the toner density of the developing device is executed inside the printer, and when this is completed, the developing device equipped with a new toner container is ready for development.

As in this embodiment, when replenishing toner, only the toner container stopped at the predetermined replacement position can be replaced. In the revolver, one toner container can be replaced by one replacement operation. Can only be exchanged. Therefore, when replacing a plurality of toner containers, it is necessary to rotate the revolver every time one toner container is replaced. When the revolver rotation is automatically performed, the toner container replacement and the recovery operation and the revolver rotation are alternately performed for each toner container replacement, and the toner container replacement and the revolver rotation are performed. A method is conceivable in which the recovery operations for the replaced toner containers are collectively performed after all the replacements for the plurality of toner containers are completed by performing the replacement alternately. In any of the methods, even when the toner container replacement or the recovery operation is executed when there is only one toner container at the toner near end or the toner end, the toner near end or at least one toner container is When the door is opened and closed in the toner end state, it is conceivable that the toner container has been replaced and the recovery operation or the like is performed.
Specifically, the information of the toner near end or the toner end is stored together with the information of which toner container these are occurring, and in the state where this information is stored, the standby state is set, and It is conceivable to perform the recovery operation or the like when the door opening / closing is detected by using the signal of the door switch input 144 or the like. (Hereinafter, margin)

However, since the toner container is not actually replaced when the door is opened and closed, it is said that the toner container is replaced only by opening and closing the door when the toner near end or the toner end occurs. In the case of performing the control to be considered, there arises a problem that a wasteful operation such as a recovery operation is performed, or the device cannot be used during this operation.

Therefore, in the printer of this embodiment, when the change in the presence or absence of the toner container is detected by using the output of the toner container sensor 143 which detects the presence or absence of the toner container at the replacement position, the toner container is detected. The control is performed to consider that the replacement has been performed. Specifically, when the toner container sensor 143 and the output of the door switch input 144 are used, the toner container is once removed with the door opened under the toner near end or the toner end, and then set. In addition, control is performed to regard that the toner container has been replaced.

Even if the toner container has been replaced, the operator cannot judge that the toner container has been replaced.
There is a possibility that a person different from the operator who exchanged the toner may come and exchange the same toner container again. Therefore, in the printer according to the present embodiment, when it is determined that the toner container has been replaced, a message indicating that the toner container has been replaced is displayed. This display is performed by turning off the LED display of the toner end when the toner container replacement is recognized. This allows the operator to recognize that the toner container has been replaced.

Further, in the printer of this embodiment, when the door is opened and closed, the developing device is stopped at the regular position so that the next image formation can be immediately performed normally regardless of the stop condition. Further, the homing operation is executed so that the mark position of the intermediate transfer belt 30 is stopped at a predetermined position from the mark sensor 150. During this homing operation, if the revolver is rotated in order to stop the developing device at the normal position, the toner remaining at the joint between the revolver side revolver and the toner container may be scattered inside the device. . Therefore, in the printer according to the present embodiment, when it is determined that there is no toner container, the revolver is not moved, that is, the homing operation is not performed, and the recovery operation is not performed. Then, the mounting of the toner container is encouraged.

FIG. 16 is a flow chart of a control example when opening and closing the door in this embodiment. This processing is executed by the CPU 101 shown in FIG. It should be noted that lighting of the LED indicating the state of the printer, displaying a message prompting the user to operate, or inputting an instruction from the user is performed through a control panel (not shown) on the printer body.

First, the door switch 144 (FIG. 4) detects whether the door of the printer body is closed (step 201). Here, when the door is open, the state of the door open flag is determined (step 202),
If the door open flag is on, the process ends. If it is off, the door open flag is turned on (step 203) and the process ends. When the door is closed in step 201, the state of the door open flag is determined (step 204). If the door open flag is off, the process ends. If the door open flag is on, the door open flag is turned off (step 20
5) Whether the toner container is present at the replacement position is detected by the toner container sensor 143 (FIG. 12) (step 206). If there is no toner container, the control panel displays "no toner container" (step 207). If there is a toner container, it is determined whether the toner container is toner end or toner near end (step 208). When the toner container is at the toner end or the toner near end, the toner end (or near end) LED of that color on the control panel is turned on (lighted). If it is not the toner end or the toner near end, the homing process described later is executed (step 209) and the process is ended.

The homing process executed in step 209 will be described. The homing process is a process for specifying the color of the toner container at the developing position and the replacement position. FIG. 17A is a flowchart showing a processing procedure when executing the homing processing. This processing is executed by the CPU 101 shown in FIG.

In this example, first, the abnormality timer is set (reset & start) (step 301), and then the pulse pattern is output to the revolver motor (FIG. 3) to rotationally move the revolver (step 302). Then, before the abnormality timer times out (N in step 303), if the home position is not detected (N in step 304), the loop of steps 302 to 304 is repeated. When the home position is detected (Y in step 304) before the abnormality timer times out (N in step 303), a predetermined pulse is output to stop the K developing device at the developing position ( Step 305). Here, it is confirmed that there is K at the developing position and M at the exchange position (step 306, step 30).
7), end. On the other hand, if the abnormality timer times out in step 303, that is, if the home position is not detected even if the abnormality timer times out, the revolver motor 113 (FIG. 3) is stopped (step 308) and the revolver abnormality process is executed. (Step 309) is performed.

Next, returning to the flowchart of FIG. 16 again, when the toner container is at the toner end or the toner near end in step 208, the state of the replacement recognition flag is judged (step 211). The replacement recognition flag is an identifier indicating whether or not the toner container has been replaced, and when the presence or absence of the toner container is changed using the output of the toner container sensor 143 by the processing shown in FIG. 17B. Then, the exchange recognition flag is turned on. That is, in FIG. 17B, when it is determined in step 401 that there is no toner container, it is determined whether the toner container flag is on or off. If it is off, the process ends. If it is on, the toner container presence flag is turned off and the process ends (step 304). After that, as long as the toner container is still removed, it is determined in step 401 that there is no toner container, and in step 403 it is determined that the toner container flag is off, and the process ends. When the toner container is attached and it is determined in step 401 that the toner container is present, it is determined in step 402 that the toner container present flag is on, the toner container present flag is turned on, and the replacement recognition flag is turned on. Yes (steps 405, 40
6). After that, unless the toner container is removed,
In step 401, it is determined that the toner container is present, and the process proceeds to step 402. Here, it is determined that the toner container flag is ON, and the process ends.

Returning again to the flowchart of FIG. 16,
If the exchange recognition flag is turned on in step 210,
First, the toner end LED of the exchange position color displayed on the control panel is turned off (step 211), and then the recovery operation of the color at the exchange position (hereinafter, exchange position color) is performed (step 212). In step 211, the toner near-end LED is turned off when the toner container of the exchange position color is in the toner near-end. However, in the following description, only the toner end LED is shown. On the other hand, when the exchange recognition flag is off in step 211, the homing process is performed (step 209) and the process ends.

In this control example, as shown in FIG. 17A, when the presence or absence of the toner container is changed by using the output of the toner container sensor 143, the replacement recognition flag which is turned on is used to change the toner. Since it is determined that the toner container has been replaced when the presence or absence of the container has changed, the toner container is actually opened and closed without detaching and attaching the toner container. Do not erroneously determine that the vessel has been replaced.

Further, in this control, as shown in steps 210 to 212 of FIG. 16, when it is determined that the toner container is replaced, first, the LED indicating the toner end or toner near end of the replacement position color is turned off. Then
Since the recovery operation is started after that, unlike the case where the above LED is continuously turned on during the recovery operation and the LED is turned off after the recovery operation is completed, there is little possibility that the toner container replacement will be repeated.

Further, in this control example, when it is determined in step 206 of FIG. 16 that there is no toner container, the control panel displays "no toner container", and the process ends (step 207). The homing process of step 209 and the recovery operation of step 212 do not proceed. That is, when it is determined that there is no toner container, control is performed to prohibit rotation of the revolver.
Therefore, it is possible to prevent the toner existing in the toner container joining portion of the revolver main body from scattering in the apparatus by performing the homing process and the process involving the revolver rotation such as the recovery operation in a state where the toner container is not attached.

By the way, in the printer of the present embodiment, the toner container sensor 143, which is a reflection type photosensor having the presence or absence of the toner container at the replacement position of the toner container, is Since there is no reflection, it is possible to detect that there is no toner container.
When the door is suddenly opened during image formation to stop the operation of the apparatus, if the revolver is stopped at a position where the sensor 143 faces such a gap, there is no toner container when the door is closed. To judge. Therefore, as in the above control example, when it is determined in step 206 of FIG. 16 that there is no toner container, the control panel displays that there is no toner container and ends (step 207). If you do, the device may remain stuck.

In order to prevent such a problem, when the cover is closed, it is determined whether the revolver is stopped during movement or stopped at the proper position. Preferably ignores the detection output of the sensor 143 and does not perform the revolver rotation prohibition control based on the detection output of the sensor 143. In the printer according to the present embodiment, as described above, the position where the toner container can be replaced is limited to one by the front cover, and
When the revolver rotation stop position is slightly displaced from the replacement position, the inner cover 630 has a cutout shape that does not allow the toner container to be taken out. Therefore, when the revolver is stopped during rotation, the toner container cannot be taken out. As a result of not performing the revolver rotation prohibition control as described above, even if the revolver is rotated, the toner container remains unattached. There is no revolver rotation and no toner scattering.

FIG. 18 is a flow chart showing an example of the above-mentioned control for determining whether the revolver is stopped during movement or stopped at the regular position when the cover is closed. The flowchart of this control example is shown in FIG.
The difference from the flowchart of the control example of No. 6 is the judgment step 2 indicated by a chain double-dashed line for judging whether the vehicle is stopped during the movement of the revolver or stopped at the regular position.
05a is added, and when it is determined in this determination step 205a that the revolver has stopped at the normal position (when it is determined that the revolver movement flag is off in step 205a), the same step as in the control of FIG. 16 is performed. On the other hand, when it is judged in the judgment step 205a that the revolver is stopped while the revolver is moving (when it is judged that the revolver moving flag is turned on in step 205a), it is determined that the toner container is present and the above-mentioned step is performed. The only difference is that step 206 is passed and step 208 is directly performed. The other points are the same as those of the control in FIG. 16, and the corresponding steps are denoted by the same step numbers.

For the judgment in the judgment step 205a, the revolver movement flag which is turned on / off by the processing shown in FIG. 19 (a) is used. The process of FIG. 19A is performed by the CPU shown in FIG. 3 with the start of the revolver rotation drive.
It is being executed at 101. When the rotational drive of the revolver is started, the revolver movement flag is turned on (step 50
1), the drive pattern is output to the revolver motor 113 (FIG. 3) (step 502). After this, it is judged whether the movement of the revolver has ended normally (step 50).
3) When the process is completed normally, the revolver movement flag is turned off (step 504). The color at the normal end is stored in the nonvolatile RAM 103 (FIG. 3). When the revolver does not end normally, for example, when the cover is opened during the revolver rotation and the revolver rotation is stopped, the operation ends as it is. As a result, the revolver movement flag is kept on. Therefore, by determining whether the revolver movement flag is on or off when the cover is closed, whether the revolver at the time of closing is in a state in which its rotation has normally completed (the flag is off), or whether the revolver is rotating. It is possible to determine whether or not it is in the stopped state (the flag is off).

By the way, as described above, when the movement of the revolver is stopped during the movement of the revolver, the cover is opened during the image forming operation, and the power switch is turned off during the image forming operation. There is also. In this case as well, when the power switch is turned on thereafter, it may be determined that there is no toner container, and the apparatus may remain stopped.

FIG. 19B is a flow chart of a control example at the time of power-on to prevent such a problem. This control is performed by the CPU 101 shown in FIG. 3 when the power is turned on.
Running in. First, when the power is turned on,
The door switch 144 (FIG. 4) detects whether the printer body door is closed (step 60).
1). When the door is open, it ends. When the door is closed, the revolver movement flag is checked. In this control example, since the on / off state of the revolver movement flag is maintained even during power-off, data relating to this is stored in the nonvolatile RAM. If this flag is off, that is, if it is determined that the revolver has stopped at the normal position, the process proceeds to step 603 to determine the presence or absence of the toner container, while if this flag is on, that is, the revolver is stopped during movement. If it is determined that the toner storage container is present, the process proceeds to step 605 in which it is determined that the toner storage container is present and the color of the replacement position is toner end or toner near end.

Then, in step 603, the toner container sensor 143 (FIG. 12) detects whether or not there is a toner container in the replacement position (step 602).
Here, if there is no toner container, it is displayed on the control panel that there is no toner container (step 60).
4). If there is a toner container at the replacement position, it is determined whether the replacement position color is toner end or toner near end (step 605). In step 605, if it is not the toner end or the toner near end, homing processing is executed (step 60
On the other hand, when the replacement position color is toner end or toner near end in step 604, the toner end (or near end) LED of the replacement position color is turned off (step 607) and the replacement position color, that is, the power is turned off. The recovery operation is executed for the color that was in the replacement position before (step 608).

In the printer of this embodiment, when the power is turned on and the replacement position color is toner end or toner near end, it is assumed that the toner container is replaced while the power is off. However, if the replacement position color is toner end or toner near end when the power is turned on, the status of the replacement recognition flag (see FIG. 16) is set for the toner container of the replacement position color. Alternatively, the recovery operation may be performed only when the exchange recognition flag is on. In this case, like the revolver movement flag, the state data of the exchange recognition flag is stored in the nonvolatile RAM.

When the control shown in FIG. 18 or 19 (b) is adopted, the revolver movement flag that remains in the ON state is
The homing process or the recovery operation may be performed to turn off the revolver rotation when the revolver rotation is normally terminated.

[0097]

According to the first aspect of the present invention, when it is determined that the toner container has been replaced, the end of the notification of the notification means for urging the toner container, which is judged to be replaced, to be replaced, is replaced. Each time it is judged, it is performed without waiting for the completion of the recovery operation.Therefore, unlike the case where the notification to prompt the replacement of the toner container is continued during the recovery operation after the replacement for the replaced toner container, the same developer is duplicated. It is possible to prevent the replacement of the toner container.

According to the second aspect of the invention, since the operation of the moving means for moving the toner container is prohibited when the toner container is not mounted, the toner container is moved with the toner container not mounted. It is possible to prevent the toner existing in the joint portion of the toner container with the toner discharge port from scattering due to the operation of the means.

According to the third aspect of the invention, when it is detected that the cover member is closed, when it is determined that the cover member is stopped during the movement based on the stored content of the storage means, Since the output of the mounting detecting means at the toner container moving position remains when the cover member is detected to be closed, the output of the mounting detecting means is ignored. Even if the toner is attached, even if the toner detector is not erroneously detected because neither toner container is located at the predetermined position where the toner detector detects. , It is possible to prevent erroneous control based on the output.

According to the fourth aspect of the present invention, when the device power switch is turned on, when it is determined that the device power switch is cut off during the movement based on the stored contents of the storage means, the state of Since the output of the mounting detection means at the toner container moving position is ignored, the state in which the toner container is stopped during the movement does not affect which toner Since the container is also not in the predetermined position where the mounting detection means detects, the erroneous control based on the output can be prevented even when the mounting detection means makes an erroneous detection. . (Hereinafter, margin)

According to the invention of claim 5, the toner accommodating means for accommodating the toner to be replenished in the developing device and for detecting the presence or absence of the detachable mounting of the toner accommodating container is based on the output of the toner accommodating means. Since the replacement criterion is used to judge whether or not the toner container has been replaced by the change in the presence or absence of the container, only the opening / closing of the device cover member opened / closed by the operator when the toner container is replaced is used. Unlike the case of adopting the replacement judgment standard that has been used, or the replacement judgment standard that is used by combining it with the information as to whether it is the toner end or the toner near end, the above-mentioned apparatus is actually used without detaching the toner container. When only the cover member is opened / closed, it is not erroneously determined that the toner container has been replaced.

[Brief description of drawings]

FIG. 1 is a block diagram showing a basic configuration of a printer according to an embodiment.

FIG. 2 is a block diagram showing the basic configuration of the printer shown in FIG.

FIG. 3 is a block diagram showing a detailed circuit configuration of a printer control unit shown in FIG.

FIG. 4 is a block diagram showing a connection between the I / O controller shown in FIG. 3 and peripheral devices.

5 is a schematic configuration diagram showing a main part of the printer unit shown in FIG.

FIG. 6 is a timing chart when outputting two A4 size black and white images.

FIG. 7 is a timing chart when outputting one A4 size full-color image.

FIG. 8 is a timing chart when outputting one A3 size full-color image.

FIG. 9 is a conceptual cross-sectional view showing the internal structure of a revolver.

FIG. 10 is a conceptual cross-sectional view showing a toner circulation path in the revolver.

FIG. 11 is a conceptual side view showing a mounted state of the toner container.

FIG. 12 is a front view showing the internal structures of a toner container and a toner hopper.

FIG. 13 is an explanatory diagram showing a state where toner moves from a toner container to a toner hopper.

FIG. 14 is an explanatory diagram in which a color at the current developing position and a target moving color are associated with each other.

FIG. 15 is an explanatory diagram in which a development position color and an exchange position color are associated with each other.

FIG. 16 is a flowchart of a control example when opening and closing a door.

17 (a) is a flowchart of homing processing executed under the control of FIG. (B) A flowchart of the process of the exchange recognition flag used for the control of FIG. 16.

FIG. 18 is a flowchart of another control example when opening and closing the door.

19 (a) is a flowchart of processing of a revolver movement flag used for the control of FIG. (B) A flowchart of a control example when the power is turned on.

[Explanation of symbols]

 10 Printer 11 Photoreceptor Drum 16 Belt Transfer Charger 20 Revolver 21 Developing Device 22 Developing Sleeve 30 Intermediate Transfer Belt 33 Paper Transfer Charger 40 Writing System Unit 101 CPU 104 Serial Communication Controller 105 Writing System Control IC 107 I / O Controller 111 Drum Motor 112 Developing motor 113 Revolver motor 143 Toner container sensor 600 Front side plate 601 Rear side plate 606 Upper conveying screw 607 Paddle 610 Toner hopper 612 Lower conveying screw 621 to 624 Toner container

Claims (5)

[Claims] 1. An image forming apparatus comprising a plurality of toner containers which are removably mounted and which accommodates toner to be replenished to a developing device. Toner presence / absence detection means for indirectly detecting, notification means for urging the replacement of each toner container based on the output of the toner presence / absence detection means, and whether or not the toner container is replaced based on a predetermined criterion. And a recovery control means for performing a predetermined recovery operation for replenishing the toner in the developing device when the toner container is replaced by the judging means. Each time it is determined that the toner is replaced based on the determination result, a notification that terminates the notification of the notification unit for the toner container that is determined to be replaced without waiting for the completion of the recovery operation An image forming apparatus characterized by providing a control means. 2. A toner container, which accommodates toner supplied to a developing device and is detachably mounted, and a toner discharge port portion of the toner container, and holds the toner container. In the image forming apparatus including a moving unit that moves the toner container in the above state, the toner container is not mounted based on the output of the mounting detection unit that detects whether or not the toner container is mounted. An image forming apparatus comprising: a movement prohibition control means for prohibiting the operation of the movement means at times. 3. A toner container having a joint between a plurality of toner containers, which accommodates toner to be supplied to a developing device and is detachably mounted, and a toner discharge port of the toner container. An image forming apparatus having a moving unit that moves the holding unit, the mounting detecting unit detecting whether or not the toner container is mounted at a predetermined position on the moving path of the toner container by the moving unit; A cover detecting unit that detects opening / closing of a device cover member that is opened / closed by an operator when the toner container is replaced, and the cover member while the moving unit drives and moves the toner container based on the output of the cover detecting unit. A movement stop control means for stopping movement by the movement means when a door is opened, and a memory for storing movement stopped by the movement stop control means during the movement. A step, and when it is detected that the cover member is closed based on the output of the cover detection means, when it is determined that the cover member is stopped during the movement based on the stored content of the storage means, An image forming apparatus, which ignores an output of the mounting detecting means at the toner container moving position when it is detected that the cover member is closed. 4. A toner container having a joint between a plurality of toner containers, which accommodates toner to be supplied to a developing device and is detachably mounted, and a toner discharge port of the toner container. An image forming apparatus including a moving unit that moves the holding unit, a mounting detecting unit that detects whether the toner container is mounted at a predetermined position on a moving path of the toner container by the moving unit; When the device power switch is cut off during movement by the moving means,
Remembering that the vehicle was moving at the time of the interruption, and
At least the storage means that can retain the stored contents until the device power switch is turned on thereafter, and when the device power switch is turned on, the device power switch is cut off during the movement based on the stored contents of the storage means. When the determination is made, the image forming apparatus is characterized in that the output of the mounting detecting means is ignored while the toner container moving position in that state is maintained. 5. An image forming apparatus having a toner container which is removably mounted and which stores toner supplied to a developing device, and mounting detection means for detecting whether or not the toner container is mounted. An image forming apparatus, comprising: a replacement determining unit that determines that the toner container has been replaced based on a change in the presence or absence of the toner container based on an output of the mounting detecting unit.