JP2002207356A - Image forming device and control method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to accurately detect a remaining quantity of a developer even when a cartridge is left for a long time and tapping is caused, in a laser printer or the like using a cartridge accommodating a developer for developing a latent image on an image carrier. SOLUTION: A memory device 127 capable of reading and writing is arranged in a developer cartridge 100 having a developing machine 107 for developing an electrostatic latent image formed on a photoreceptor drum 101 with toner. Then, this device writes date and time data at the time of switching on a power source and a door switch in the memory device 127, calculates unused hours of the cartridge 100 by comparing the present data with the precedent data, and alters multiple pre-rotating time of a main motor before applying a developing bias, according to the hours.

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 laser printer, and more particularly to an image forming apparatus using toner as a developer and a control method thereof.

[0002]

2. Description of the Related Art In an image forming apparatus such as an electrophotographic laser printer, a latent image formed on a photoreceptor is developed with toner, and this is transferred to recording paper and fixed. Since this image recording is performed using the toner contained in the developing device cartridge, a toner remaining amount detecting unit is provided at the time of image formation, so that toner supply is promoted. Further, in this image forming apparatus, since the developing cartridge is formed as a process cartridge which is detachable from the apparatus main body, the presence or absence of the process cartridge is also determined.

FIG. 10 shows a schematic configuration of the above-described cartridge presence / absence and toner remaining amount detecting device. The device for detecting the presence / absence of a cartridge and the remaining amount of toner is a developer carrier 1 of a developing device.
And the antenna 2 as an electrode member, the change in the capacitance C1 generated between the antenna 2 and the developer carrier 1 is detected by the cartridge presence / absence and toner remaining amount detection circuit 3 so that the presence / absence of the cartridge and the remaining toner amount It is to judge.

That is, when a specified AC bias value is output from the developing bias circuit 4 as a developing bias applying means and is applied to the developer carrier 1, the developer carrier 1
An AC bias value V1 corresponding to the value is applied to the capacitor C1 generated between the antenna C1 and the antenna 2. Also, an AC bias V2 is similarly applied to the impedance element 5,
This is a reference value for detecting the presence or absence of the cartridge and the remaining amount of toner. Then, the values of V1 and V2 are input to the cartridge presence / absence and toner remaining amount detection circuit 3 to determine the presence / absence of the cartridge and the remaining amount of toner.

The presence or absence of the cartridge and the detection of the remaining amount of toner are determined by turning on the power or turning on the door switch (ON).
The detection is performed when the toner is being stirred by the multi-rotation operation before the time. FIG. 11 shows a series of timing operations.

When the power is turned on or the door switch is turned on (S
1), a main motor ON signal is output from the CPU of the apparatus main body, and the above-mentioned pre-multi-rotation is started (S2). Subsequently, by turning on the charging AC bias at the same time as the motor ON (S3), the cartridge (C
RG) is determined (S4). If there is a cartridge, the developing AC bias is turned on (S5), and it is determined whether there is a remaining amount of toner (S6). Then, if toner remains, after the transfer negative bias is applied (ON) (S7), the pre-multiple rotation is completed and the apparatus enters a standby state (S8).

If there is no cartridge and toner in S4 and S6, respectively, the pre-multi-rotation is completed at that point and the apparatus enters a standby state.

[0008]

In the above-described image forming apparatus, tapping occurs when the toner cartridge is left for a long period of time. However, the toner cannot be pulverized by a normal pre-multi-rotation operation. If the toner cannot be sufficiently crushed, there is a problem that the remaining amount of the toner cannot be accurately detected.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and it is possible to sufficiently pulverize the developer even if tapping occurs, and to accurately detect the remaining amount of the developer. It is an object of the present invention to provide an image forming apparatus and a control method therefor.

[0010]

According to the present invention, there is provided an image forming apparatus, comprising: a container for storing a developer for developing a latent image formed on an image carrier; and a residual amount of the developer in the container. The developing cartridge includes a remaining amount detecting unit for detecting, a date and time detecting unit for detecting a date and time, and the developing cartridge includes a storage unit for storing detection information of the date and time detecting unit.

The remaining amount detecting means has a pair of electrodes for a capacity measuring function, and a capacitance between the other electrode and the developer carrier when a developing bias is applied to one of the electrodes. And the capacitance between the pair of electrodes at that time are added, and the remaining amount of the developer is calculated from the added value.

Further, a memory device capable of reading and writing information is used as the storage means, and information of date and time when the image forming operation state is entered is updated and written into the memory device as needed, A date and time information when the power supply or the door switch is turned on is read from the memory device, and the read information is compared with the date and time information when the power supply or the door switch is turned on next. Is detected, and the multi-rotation operation before stirring the developer is changed based on the detection result.

A method for controlling an image forming apparatus according to the present invention comprises:
A method for controlling an image forming apparatus using a developing cartridge having a container for storing a developer for developing a latent image formed on an image carrier, comprising: a developer remaining amount and a date in the container; The time information is stored in a memory device provided in the developing cartridge.

Further, when detecting the remaining amount of the developer in the container, when a developing bias is applied to one of the pair of electrodes, an electrostatic force between the other electrode and the developer carrying member is detected. The capacitance and the capacitance between the pair of electrodes at that time are added, and the remaining amount of the developer is calculated from the added value.

Further, date and time information at the time of the image forming operation state is updated and written into the memory device as needed, and the date and time information at the time of turning on the power of the image forming apparatus main body or the door switch is turned on. Is read from the memory device, and the read information is compared with the date and time information when the power supply or the door switch is next turned on to detect a period in which the developing cartridge is left unattended, and based on the detection result, The multi-rotation operation is changed before stirring the developer.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram schematically showing the configuration of an image forming apparatus according to the present invention. Here, a cross-sectional configuration of the above-described laser printer is shown as an example.

In FIG. 1, reference numeral 101 denotes a photosensitive drum, which is an electrostatic image carrier having a photosensitive layer; 102, a semiconductor laser as a light source; 103, a rotating polygon mirror rotated by a scanner motor 104; Is a laser beam emitted from and scans the photosensitive drum 101.

Reference numeral 106 denotes a charging roller for uniformly charging the photosensitive drum 101, and 107 denotes a photosensitive drum 101.
The developing device develops the electrostatic latent image formed thereon with toner. The developing device is provided integrally with other components in a developing cartridge 100 detachable from the printer main body 200. Reference numeral 108 denotes a transfer roller for transferring the toner image developed by the developing device 107 onto a predetermined recording sheet, and reference numeral 109 denotes a fixing roller for fusing the toner transferred to the recording sheet by heat.

Reference numeral 110 denotes a cassette paper feed roller for feeding recording paper from a cassette having a function of identifying the size of the recording paper by one rotation and feeding the recording paper to a conveyance path;
Reference numeral 1 denotes a manual paper feed roller for feeding recording paper from a manual paper feed port which does not have a function for identifying the size of recording paper to a transport path. Reference numeral 112 denotes a function that is detachable from the printer main body 200 and identifies the size of recording paper. An optional cassette paper feed roller for feeding recording paper from a cassette provided to the conveyance path, an envelope feeder paper feed roller 113 for feeding recording paper one by one from an envelope feeder detachable to the printer main body 200 and capable of loading only envelopes, 114 and 115 are conveying rollers for conveying the recording paper fed from the cassette.

Reference numeral 116 denotes a pre-feed sensor for detecting the leading and trailing ends of recording paper fed from a source other than the envelope feeder; 117, a pre-transfer roller for feeding the transported recording paper to the photosensitive drum 101; A top sensor for synchronizing the image writing (recording / printing) on the photosensitive drum 101 with the fed recording paper and the conveyance of the paper, and measuring the length of the fed recording paper in the conveyance direction. Reference numeral 119 denotes a paper discharge sensor for detecting the presence or absence of fixed recording paper, and reference numeral 120 denotes a discharge roller for discharging the fixed recording paper outside the apparatus.

Reference numeral 121 denotes a flapper for switching a destination (a double-sided unit that can be ejected or detached) of printed recording paper, 122 a transport roller for transporting the paper transported to the duplex unit to a reversing unit, and 123 a reversing unit. Reversing sensor for detecting the front / rear end of the recording paper conveyed to
124 is a reversing roller for reversing the recording sheet by sequentially operating forward / reverse rotation and transporting the sheet to a re-feeding unit, 125 is a re-feeding sensor for detecting the presence or absence of a sheet in the re-feeding unit, and 126 is a re-feeding sensor. This is a re-feed roller that re-feeds the recording paper of the re-feed section to the transport path.

Reference numeral 127 denotes a memory device, which is a readable and writable storage unit provided in the developing cartridge 100, in which detection information of a remaining toner amount and detection information (date and time) of a date and time detection unit having a clock function (not shown) are written. And the information is read out.

The developing cartridge 100 includes:
A container for accommodating a toner as a developer, a remaining amount detecting means for detecting a remaining amount of the toner in the container;
1 and the like are arranged in a predetermined positional relationship. In other words, the developer carrying member that is arranged to face the photosensitive drum 101 and carries and transports the toner, the above-described container that stores the toner to be supplied to the developer carrying member, the toner remaining amount detecting device, etc. Printer body 20 as a cartridge
0 is detachably provided.

FIG. 2 is a block diagram showing a circuit configuration of a control system of the printer having the above configuration. Referring to FIG. 1, reference numeral 201 denotes a printer controller which expands image code data transmitted from an external device such as a host computer (not shown) into bit data necessary for printing by the printer, and reads and displays information inside the printer. Each part of the printer engine is controlled in accordance with an instruction from the printer controller 201, and the printer controller 20 is controlled.
1 is a printer engine control unit that reports printer internal information.

Reference numeral 203 denotes a paper transport control unit which drives / stops a motor and rollers for transporting recording paper in accordance with an instruction from the printer engine control unit 202; A high-voltage control unit that controls high-voltage output in accordance with instructions from the printer engine control unit 202; an optical system control unit 205 that controls driving / stopping of the scanner motor 104 and lighting of the laser beam 105 in accordance with instructions from the engine control unit 202; 2
Reference numeral 06 denotes a sensor input unit for inputting a signal from each sensor.

Reference numeral 207 denotes a fixing unit temperature control unit for adjusting the temperature of the fixing unit to a temperature designated by the printer engine control unit 202. Reference numeral 208 denotes a detachable optional cassette control unit.
The drive system is driven / stopped according to an instruction from the printer engine control unit 202, and a paper presence / absence state and paper size information are notified to the printer engine control unit 202.

Reference numeral 209 denotes a detachable double-sided unit control unit which performs a reversing operation and a re-feeding operation of a recording sheet in accordance with an instruction from the printer engine control unit 202, and notifies the engine control unit 202 of the operation state. Reference numeral 210 denotes a detachable envelope feeder control unit that drives / stops a drive system in accordance with an instruction from the printer engine control unit 202 and notifies the printer engine control unit 202 of a paper presence / absence state.

The printer engine control unit 202 also serves as a control unit for the memory device 127, and updates the date and time information in the print operation state (image formation operation state) to the memory device 127 as needed. At the same time, the date and time information when the power supply or the door switch of the printer main body 200 is turned on is read from the memory device 127, and the read information and the date and time when the power supply or the door switch is next turned on are read. The information is compared with the developing cartridge 100
Is detected, and the multi-rotation operation before stirring the toner is changed based on the detection result.

FIG. 3 is a diagram showing the configuration of the toner remaining amount detecting device of the present embodiment. FIG. 4 is a diagram showing a configuration of the detection circuit.

In FIGS. 3 and 4, reference numeral 301 denotes a developing bias circuit for applying a developing bias, and a developer carrier (developing sleeve) 302 and a pair of electrodes 303,
304 is connected to one electrode 304 and the other electrode 30
Control circuit 306 of the toner remaining amount detection circuit 305 via
It is connected to the. The developing bias circuit 301
Is also connected to the impedance element 307. The impedance element 307 is connected to the control circuit 306, and the current I3 flows. This current I3 is equal to the resistance R1
2 shunts currents I5 and I6. The reference voltage V4 is determined by the divided current I6 and the set voltage of the resistor R11.

As shown in FIG. 3, the pair of electrodes 303 and 304 are arranged at a predetermined interval in the cartridge.
The cartridge capacity between the 03-electrode 304 is connected to the control circuit 306. Therefore, the control circuit 30
The AC current I4 applied to 6 becomes I1 + I2, which is applied to the amplifier circuit 308, from which the detection value V6 (= V4−I4 × R10) of the remaining amount of toner is output.

In FIG. 4, reference numeral 309 denotes a rectifier (diode) 310 denotes an operational amplifier which is a comparison circuit, and C5 and C
6, C7 indicates a container (condenser), and R1, R2, R3, and R10 indicate resistors.

(Embodiment 1) This embodiment is provided with a system having a function of measuring a capacitance for detecting a toner amount, and a function of detecting a date / date and a non-contact type memory device function. It is characterized by having a configuration that is

FIG. 5 is a flowchart showing the main operation of this embodiment, and FIG. 6 is a flowchart showing the specific operation. FIG. 7 is a time chart showing the operation of each part of the present embodiment. The control processing of the flowcharts shown in FIGS. 5, 6, and FIG.
Is executed in accordance with a program stored in advance by the CPU.

In the standby state (S11), when a print ON signal is output from a CPU (not shown) (S1).
2) The communication with the memory device 127 is performed, and the date / time information is written in the memory device 127 (S13). The date / time information is updated as needed when printing is performed. When the printing is completed (S14), the process returns to the standby state.

Here, in the above-mentioned main operation, the power is turned on.
When the door switch is turned ON (S101), it is determined whether or not there is a cartridge (CRG) by communicating with the memory device 127 (S102) (S10).
3). If there is no cartridge, the user is notified that there is no cartridge (S110). If there is a cartridge, the communication with the memory device 127 is continued to read the date / time data (S104). Then, the main motor ON signal is output from the CPU (S
105), pre-multi-rotation is started.

At this time, the previous date / time data is compared with the date / time data when the power supply is turned on or the door switch is turned on, and the motor is rotated according to the resulting cartridge leaving time. The time from application until the application of the developing bias is varied. By varying this time, it is possible to detect the remaining amount of toner after the tapping is eliminated. This toner detection method is as described above. The maximum value, the minimum value or the average value of the detection value V6 is detected, and the remaining toner amount is calculated from the detected value. When this detection value V6 is output, the remaining amount of toner currently in the cartridge is calculated.

Next, the developing AC bias is turned on (S10).
6) It is determined whether there is a remaining amount of toner (S10).
7). If there is no toner, the absence of toner is displayed to the user (S111). If there is toner, after the transfer negative bias is applied (ON) (S108), the pre-multi-rotation is completed and the apparatus enters the standby state (S109).

In FIG. 7, the variable area (time) described above is the presence / absence detection of the cartridge, date / time data reading, toner remaining amount detection, transfer roller cleaning, and multi-rotation operation before (motor (During operation).

As described above, in this embodiment, in a system having a function of detecting the date and time and having a memory function in the toner cartridge, data (date and time) at the time of printing is stored in the memory. Means for writing the data (date / time) whenever printing is performed; means for reading the data (date / time) when the power supply and the door switch are turned on; Data (date and time)
, A comparing means for comparing the data (date and time), and a variable means for varying the pre-multiple rotation time according to a period during which the toner cartridge obtained from the comparison result is not used. I have.

Accordingly, even if tapping occurs, the toner can be sufficiently pulverized, and the remaining amount of the toner can be accurately detected.

(Embodiment 2) This embodiment also has a system having a function of measuring capacitance to detect the amount of toner, and a function of detecting date / date and a non-contact type memory device function. It is characterized by having a configuration that is

FIG. 5 is a flowchart showing the main operation of this embodiment, and FIG. 8 is a flowchart showing the specific operation. FIG. 9 is a time chart showing the operation of each part of the present embodiment.

Since the main operation of this embodiment is the same as that of the above-described embodiment, the description is omitted.
When N is reached (S201), the main motor is turned on (S201).
202), start multi-rotation before. By turning on the charging AC bias at the same time when the motor is turned on (S203), it is determined whether or not there is a cartridge (S204). If there is no cartridge, the user is informed that there is no cartridge (S211). If a cartridge is present, communication with the memory device 127 is performed (S205), and date / time data is read (S20).
6).

At this time, the previous date / time data is compared with the date / time data when the power is turned on or the door switch is turned on, and the memory device 127 is stored in the memory device 127 in accordance with the resulting cartridge leaving time. The time from the end of the communication to the application of the developing bias is varied. By varying this time, it is possible to detect the remaining amount of toner after the tapping is eliminated. Since the toner detection is the same as that in the above-described embodiment, the description is omitted.

Next, the developing AC bias is turned on (S20).
7) It is determined whether there is a remaining amount of toner (S20).
8). If there is no toner, the absence of toner is displayed to the user (S212). If there is toner, the transfer negative bias is applied (ON) (S209).

In FIG. 9, the variable area (time) described above indicates the presence / absence of the cartridge, indicates the date / time data, indicates the remaining amount of toner, indicates the transfer roller cleaning, and indicates the multi-rotation operation (the motor is (During operation).

In this embodiment, similarly to the above-described embodiment, even if tapping occurs when the toner cartridge is left for a long time, the toner can be sufficiently pulverized by changing the pre-multiple rotation time, and the remaining toner amount can be reduced. Can be accurately detected.

[0050]

As described above, according to the present invention,
Even if tapping occurs, the developer can be sufficiently pulverized, and the effect of accurately detecting the remaining amount of the developer can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a configuration of a printer according to the present invention.

FIG. 2 is a block diagram showing a circuit configuration of a control system of the printer in FIG.

FIG. 3 is a diagram illustrating a configuration of a toner remaining amount detection device according to an embodiment of the present invention.

FIG. 4 is a diagram showing a configuration of a detection circuit in FIG. 3;

FIG. 5 is a flowchart showing a main operation of the embodiment.

FIG. 6 is a flowchart showing the operation of the first embodiment.

FIG. 7 is a time chart showing the operation of each unit of the first embodiment.

FIG. 8 is a flowchart showing the operation of the second embodiment.

FIG. 9 is a time chart showing the operation of each part of the second embodiment.

FIG. 10 shows a conventional example.

FIG. 11 is a flowchart showing the operation of the conventional example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 developing cartridge 101 photosensitive drum (electrostatic image carrier) 107 developing machine 127 memory device 200 printer body 201 printer controller 202 printer engine controller 301 developing bias circuit 302 developer carrier 303 electrode 304 electrode 305 remaining toner detecting circuit 306 Control circuit 308 Amplification circuit 310 Operational amplifier (comparison circuit)

Claims (10)

[Claims] 1. A developing cartridge comprising: a container for storing a developer for developing a latent image formed on an image carrier; and a remaining amount detecting unit for detecting a remaining amount of the developer in the container; An image forming apparatus comprising: date and time detecting means for detecting date and time; and storage means for storing detection information of the date and time detecting means in the developing cartridge. 2. The image forming apparatus according to claim 1, wherein the remaining amount detecting means has a capacity measuring function for measuring a capacitance between the developer carrying member for carrying and transporting the developer. apparatus. 3. The image forming apparatus according to claim 1, wherein the date and time detecting means has a clock function. 4. The remaining amount detecting means has a pair of electrodes for a capacity measuring function, and detects a capacitance between the other electrode and the developer carrier when a developing bias is applied to one of the electrodes. ,
4. The image forming apparatus according to claim 2, wherein the electrostatic capacity between the pair of electrodes at that time is added, and the remaining amount of the developer is calculated from the added value. 5. The image forming apparatus according to claim 1, wherein said storage means is a memory device capable of reading and writing information. 6. A control unit for controlling the memory device, wherein the control unit updates and writes information on a date and time when the image forming operation state is entered into the memory device as needed, and controls the image forming apparatus main body. The date and time information when the power supply or door switch is turned on is read from the memory device, and the read information is compared with the date and time information when the power supply or door switch is next turned on to develop the image. 6. The image forming apparatus according to claim 5, wherein a period during which the cartridge is left is detected, and the multi-rotation operation before stirring the developer is changed based on a result of the detection. 7. A method for controlling an image forming apparatus using a developing cartridge having a container for storing a developer for developing a latent image formed on an image carrier, comprising: A method for controlling an image forming apparatus, wherein information on a remaining amount, date, and time is stored in a memory device provided in the developing cartridge. 8. The image according to claim 7, wherein the remaining amount of the developer is detected by measuring a capacitance between the developer carrying member that carries and transports the developer. A method for controlling a forming apparatus. 9. A capacitance between the other electrode and the developer carrier when a developing bias is applied to one of the pair of electrodes, and a capacitance between the pair of electrodes at that time. 9. The method according to claim 8, wherein the remaining amount of the developer is calculated from the added value. 10. The date and time information at the time of the image forming operation state is updated and written in the memory device as needed, and the date and time information at the time of turning on the power supply or the door switch of the image forming apparatus main body. Is read from the memory device, and the read information is compared with the date and time information when the power supply or the door switch is turned on next to detect a period in which the developing cartridge is left unattended, and based on the detection result, The method according to any one of claims 7 to 9, wherein the multi-rotation operation before stirring the developer is changed.