Image forming apparatus

Abstract

The invention provides an image forming apparatus which performs image formation at appropriate density in a case where a toner cartridge having black and a toner cartridge having a color different from the black are attached. An image forming apparatus includes a toner cartridge, a drum cartridge, an apparatus main body, a bias voltage applying circuit, and a control unit. The control unit controls the bias voltage applying circuit to apply a first developing bias voltage to the developing roller based on information of a first toner when an image is formed in a state in which a first toner cartridge is mounted, the first toner cartridge accommodating a black first toner in a toner accommodating chamber and storing the information of the first toner in a toner memory, and the first developing bias voltage applying circuit applying the first developing bias voltage to the developing roller based on the information of the first toner. When an image is formed in a state where a second toner cartridge is mounted, a second developing bias voltage different from the first developing bias voltage is applied to the developing roller based on information of a second toner, the second toner cartridge accommodates the second toner having a color different from black in a toner accommodating chamber, and the information of the second toner is stored in a toner memory.

Description

Technical Field

[0001] This invention relates to an image forming apparatus capable of mounting a toner cartridge. Background Technology

[0002] Previously, image forming apparatuses capable of housing toner cartridges were known (see Patent Document 1). In such apparatuses, toner cartridges containing black toner and toner cartridges containing red toner can be selectively installed. A magnet corresponding to the color of the toner is disposed on the top plate of the toner cartridge, and by detecting the magnet, the color of the toner in the installed toner cartridge can be determined.

[0003] Patent Document 1: Japanese Patent Application Publication No. 61-245177

[0004] However, in order to achieve proper image formation, it is necessary to apply a bias voltage suitable for the toner. Therefore, it is necessary to obtain information on applying appropriate bias voltages to the toners contained in the toner cartridges for black and colors other than black. Summary of the Invention

[0005] Therefore, the object of the present invention is to form an image at an appropriate concentration when a black toner cartridge and a toner cartridge of a different color than black are installed.

[0006] The image forming apparatus for achieving the above-mentioned objectives includes a toner cartridge, a drum cartridge, an apparatus body, a bias voltage application circuit, and a control unit.

[0007] The toner cartridge includes a toner receiving chamber, a developing roller, and a toner storage unit. The drum cartridge includes a photosensitive drum. The main body of the device can mount the toner cartridge and the drum cartridge. A bias voltage application circuit can apply a bias voltage.

[0008] The control unit controls the bias application circuit. When image formation is performed with a first toner cartridge installed as a toner cartridge, a first developing bias is applied to the developing roller based on the first toner information. The first toner cartridge contains black first toner in the toner storage chamber and stores the first toner information in the toner memory. The first toner information is the information of the first toner.

[0009] The control unit controls the bias application circuit. When image formation is performed with a second toner cartridge installed as a toner cartridge, a second developing bias voltage different from the first developing bias voltage is applied to the developing roller based on the second toner information. The second toner cartridge contains a second toner of a different color than black in the toner storage chamber and stores the second toner information in the toner memory. This second toner information is the information of the second toner.

[0010] When a first toner cartridge is installed, the control unit applies a first developing bias voltage to the developing roller based on the first toner information stored in the toner memory. When a second toner cartridge is installed, the control unit applies a second developing bias voltage to the developing roller based on the second toner information stored in the toner memory. Thus, when black and toner cartridges of different colors are installed, images can be formed at appropriate concentrations respectively.

[0011] Alternatively, the main body of the device can be equipped with either the first toner cartridge or the second toner cartridge.

[0012] In addition, the drum unit can also be fitted with a toner cartridge. Furthermore, the main body of the device can also be fitted with a toner cartridge mounted in the drum unit.

[0013] By installing the toner cartridge onto the main body of the device while it is mounted in the drum, it can be easily installed onto the main body of the device.

[0014] The drum unit can also include a charger for charging the photosensitive drum. Furthermore, the control unit can control the bias application circuit to apply a first charging bias voltage to the charger based on the first toner information when image formation is performed with the first toner cartridge installed. Moreover, the control unit can also control the bias application circuit to apply a second charging bias voltage, different from the first charging bias voltage, to the charger based on the second toner information when image formation is performed with the second toner cartridge installed.

[0015] When the first toner cartridge is installed, the control unit applies a first charging bias voltage to the charger. When the second toner cartridge is installed, the control unit applies a second charging bias voltage, thereby enabling image formation at appropriate concentrations for toner cartridges of black and colors other than black.

[0016] The first toner information may also include the value of the first developing bias voltage. Furthermore, the second toner information may also include the value of the second developing bias voltage.

[0017] The first toner information includes the value of a first developing bias voltage, and the second toner information includes the value of a second developing bias voltage, thereby enabling the application of an appropriate developing bias voltage corresponding to the first toner and the second toner.

[0018] It may also include a main memory that stores the value of the reference development bias voltage. Furthermore, the second toner information may also include the deviation value of the second development bias voltage relative to the reference development bias voltage.

[0019] The second toner information includes the deviation of the second developing bias from the reference developing bias, thereby enabling the application of appropriate developing bias values ​​corresponding to the first and second toners.

[0020] The main body of the device may also have a display unit for displaying information. Furthermore, the control unit may be a structure that displays the color of the toner contained in the installed toner cartridge on the display unit based on first toner information or second toner information read from the toner memory.

[0021] By displaying the color of the toner contained in the installed toner cartridge on the display unit, the color of the toner in the installed toner cartridge can be easily understood.

[0022] The drum cartridge may also have a cleaning roller that contacts and rotates with the outer peripheral surface of the photosensitive drum. Furthermore, both the first and second toners may be positive toners. Moreover, when image formation is performed with the first or second toner cartridge installed, the control unit may apply a positive cleaning bias voltage to the cleaning roller.

[0023] When a positive bias voltage is applied to the cleaning roller, paper dust that is charged with a negative polarity is recovered by the cleaning roller, while residual color powder that is charged with a positive polarity is not recovered by the cleaning roller.

[0024] The drum box may also have a secondary cleaning roller that contacts and rotates with the outer peripheral surface of the cleaning roller. Furthermore, the control unit can control the bias application circuit to apply a positive bias voltage to the secondary cleaning roller that is larger than that of the cleaning roller.

[0025] By applying a bias voltage with a larger positive polarity than that applied to the secondary cleaning roll, paper dust adhering to the cleaning roll can be effectively recovered.

[0026] The drum cartridge may also include a drum memory. Furthermore, the control unit may store the usage history of image formation using the first toner cartridge and the usage history of image formation using the second toner cartridge in the drum memory.

[0027] It is possible to confirm the usage history of the first and second toner cartridges to appropriately modify the image forming controls.

[0028] An image forming apparatus for achieving the above-mentioned objectives includes a processing box, an apparatus body, a bias voltage application circuit, and a control unit.

[0029] The processing cartridge includes a toner receiving chamber, a developing roller, a photosensitive drum, and a toner storage unit. The processing cartridge can be mounted on the main body of the device. A bias voltage application circuit can apply a bias voltage.

[0030] The control unit controls the bias application circuit. When image formation is performed with the first processing box installed as a processing box, a first developing bias is applied to the developing roller based on the first toner information. The first processing box contains black first toner in the toner storage chamber and stores the first toner information in the toner memory. The first toner information is the information of the first toner.

[0031] The control unit controls the bias application circuit. When image formation is performed with a second processing box installed as a processing box, a second developing bias voltage different from the first developing bias voltage is applied to the developing roller based on the second toner information. The second processing box contains a second toner of a different color than black in the toner storage chamber and stores the second toner information in the toner memory. This second toner information is the information of the second toner.

[0032] When a first processing cartridge is installed, the control unit applies a first developing bias voltage to the developing roller based on the first toner information stored in the toner memory. When a second processing cartridge is installed, the control unit applies a second developing bias voltage based on the second toner information stored in the toner memory. This allows for image formation at appropriate concentrations when processing cartridges of black and colors other than black are installed.

[0033] According to the present invention, it is possible to form images at appropriate concentrations when a toner cartridge containing black and a different color than black are installed. Attached Figure Description

[0034] Figure 1 This is a cross-sectional view of the image forming apparatus according to the embodiment.

[0035] Figure 2 It is a cross-sectional view showing the state of the drum and toner cartridges after they have been removed from the main body of the device.

[0036] Figure 3 This diagram illustrates the application of bias voltage by the bias voltage application circuit.

[0037] Figure 4 This is a flowchart illustrating the operation of the control unit in the first embodiment.

[0038] Figure 5 This is a flowchart illustrating the operation of the control unit in the second embodiment.

[0039] Figure 6 This is a table illustrating an example of image formation when the toner color and bias value are changed in a toner cartridge of type A.

[0040] Figure 7 This is a table illustrating an example of image formation when the toner color and bias value are changed in a type B toner cartridge. Detailed Implementation

[0041] The first embodiment of the present invention will now be described with reference to the accompanying drawings.

[0042] In the following description, the orientation of the image forming apparatus 1 will be... Figure 1Set the right side of the center as "front", the left side as "back", the front side as "left", and the inside side as "right". Additionally, set... Figure 1 The vertical direction in the text is set to "up and down".

[0043] like Figure 1 As shown, the image forming apparatus 1 is a laser printer. The image forming apparatus 1 is a monochrome printer capable of printing using only one color. The image forming apparatus 1 includes an apparatus body 2, a supply unit 3, an exposure unit 4, a drum cartridge 5, a toner cartridge 6, and a fixing unit 7.

[0044] The device body 2 has a front cover 21 and a display unit 22. The front cover 21 is disposed at the front of the device body 2. The front cover 21 is capable of... Figure 1 The closing position shown and Figure 2 The device body 2 is opened and closed by moving between the shown open and closed positions. When the cover 21 is in the closed position, it covers the opening 2A of the device body 2. When the cover 21 is in the open position, it opens the opening 2A of the device body 2. A display unit 22 is disposed on the upper surface of the device body 2. The display unit 22 displays information. The display unit 22 is, for example, a liquid crystal panel.

[0045] The supply unit 3 is located at the lower part of the main body 2 of the device. The supply unit 3 includes a supply tray 31, a pressure plate 32, and a paper feeding mechanism 33. The supply tray 31 holds the sheet S. The pressure plate 32 causes the sheet S held in the supply tray 31 to move upward. The paper feeding mechanism 33 supplies the sheet S, which is moved upward by the pressure plate 32, to the drum 5.

[0046] Exposure device 4 is disposed on the upper part of device body 2. Exposure device 4 includes a laser light-emitting part (not shown), a faceted mirror (omitted), a lens, a reflector, etc. In this exposure device 4, a laser beam (refer to the dotted line) based on image data emitted from the laser light-emitting part is scanned at high speed on the surface of the photosensitive drum 52, thereby exposing the surface of the photosensitive drum 52.

[0047] The drum box 5 is positioned below the exposure device 4. The drum box 5 is detachable from the main body 2 of the device. The drum box 5 includes a drum frame 51, a photosensitive drum 52, a charger 53, a transfer roller 54, a cleaning roller 55, a secondary cleaning roller 56, and a drum memory 57.

[0048] The photosensitive drum 52, transfer roller 54, cleaning roller 55, and secondary cleaning roller 56 are supported by the drum frame 51 and are rotatable. The charger 53 and drum memory 57 are supported by the drum frame 51.

[0049] The charger 53 is positioned opposite the photosensitive drum 52. The charger 53 charges the photosensitive drum 52.

[0050] The transfer roller 54 is positioned opposite to the photosensitive drum 52. The transfer roller 54 transfers the toner image formed on the photosensitive drum 52 onto the sheet S between itself and the photosensitive drum 52.

[0051] The cleaning roller 55 is disposed opposite to the photosensitive drum 52. The cleaning roller 55 contacts and rotates with the outer peripheral surface of the photosensitive drum 52. The cleaning roller 55 is used to remove debris and paper dust from the outer peripheral surface of the photosensitive drum 52.

[0052] The secondary cleaning roller 56 is arranged opposite to the cleaning roller 55. The secondary cleaning roller 56 contacts and rotates with the outer peripheral surface of the cleaning roller 55. The secondary cleaning roller 56 is used to recycle the waste and paper dust collected by the cleaning roller 55.

[0053] The drum memory 57 is a storage medium that stores information about the drum housing 5. The drum memory 57 is, for example, an IC chip with NVM (Non-Volatile Memory). Information related to the drum housing 5 includes, for example, the serial number, the cumulative number of printed sheets, and the cumulative number of rotations of the photosensitive drum 52.

[0054] The toner cartridge 6 is positioned below the exposure apparatus 4. The toner cartridge 6 is detachable from the apparatus body 2. The toner cartridge 6 can be installed in the drum cassette 5. In this embodiment, the toner cartridge 6 is positioned within the apparatus body 2 in a state of being installed in the drum cassette 5. The toner cartridge 6 includes a toner receiving chamber 61, a developing roller 62, a supply roller 63, a layer thickness limiting scraper 64, and a toner memory 65.

[0055] The toner receiving chamber 61 contains toner. In this embodiment, the toner is positively polar. The developing roller 62 supplies toner to the photosensitive drum 52. The supply roller 63 supplies toner from the toner receiving chamber 61 to the developing roller 62. The thickness limiting scraper 64 limits the toner supplied to the developing roller 62 to a certain thickness.

[0056] The toner memory 65 is a storage medium for storing toner cartridge information. The toner memory 65 may be, for example, an IC chip with NVM (Non-Volatile Memory). Toner cartridge information may include, for example, a serial number, the cumulative number of printed sheets, and the cumulative number of rotations of the developing roller 62.

[0057] In the drum cassette 5, the surface of the photosensitive drum 52 is uniformly positively charged by the charger 53 and then exposed by a high-speed scan of a laser from the exposure device 4. This causes a decrease in the potential of the exposed portion, forming an electrostatic latent image based on image data on the photosensitive drum 52. Meanwhile, toner in the toner storage chamber 61 is supplied to the developing roller 62 via the supply roller 63. The toner supplied to the developing roller 62 is then formed into a thin layer of a certain thickness and carried on the developing roller 62 by the layer thickness limiting scraper 64.

[0058] Toner carried on the developing roller 62 is supplied from the developing roller 62 to the electrostatic latent image formed on the photosensitive drum 52. Thus, the electrostatic latent image is visualized, forming a toner image on the photosensitive drum 52. Subsequently, by conveying the sheet S between the photosensitive drum 52 and the transfer roller 54, the toner image on the photosensitive drum 52 is transferred onto the sheet S.

[0059] The fixing unit 7 is located behind the drum cassette 5. The fixing unit 7 includes a heating unit 71 and a pressure roller 72. The heating unit 71 includes a halogen heater (not shown), a fixing belt, a clamping plate, etc. The pressure roller 72 clamps the fixing belt between itself and the clamping plate of the heating unit 71. In this fixing unit 7, the toner image transferred onto the sheet S is thermally fixed while the sheet S passes between the heating unit 71 and the pressure roller 72. The sheet S with the toner image thermally fixed is discharged by the discharge roller 23 onto the discharge tray 24.

[0060] Furthermore, in this image forming apparatus 1, a so-called "clean-free" method is employed, where residual toner that was not transferred to the film S and remains on the photosensitive drum 52 is recovered by the toner cartridge 6 and reused. Specifically, during the recovery of residual toner, the surface of the photosensitive drum 52 is charged once by the charger 53, making the surface potential of the photosensitive drum 52 higher than that of the developing roller 62. As a result, the positively charged residual toner on the photosensitive drum 52 moves towards the developing roller 62 and returns to the toner storage chamber 61.

[0061] like Figure 2 As shown, when the cover 21 is in the open position, the drum cartridge 5 and the toner cartridge 6 can be installed or removed from the exposed opening 2A. The main body 2 can be equipped with only either the first toner cartridge 6B or the second toner cartridge 6M.

[0062] The first toner cartridge 6B is a toner cartridge that houses a black first toner TB. When the first toner cartridge 6B is installed in the device body 2, an image is formed using the black first toner TB. The first toner information is stored in the toner memory 65B of the first toner cartridge 6B.

[0063] The first toner information includes the value of the first charging bias voltage Vg1 and the value of the first developing bias voltage Vb1.

[0064] The value of the first charging bias voltage Vg1 is the optimal charging bias voltage value when forming an image of the first black pigment TB. For example, the value of the first charging bias voltage Vg1 is 850V.

[0065] The value of the first development bias voltage Vb1 is the optimal development bias voltage value when forming an image of the first black toner TB. For example, the value of the first development bias voltage Vb1 is 300V.

[0066] The second toner cartridge 6M is a toner cartridge that houses a magenta second toner TM. Magenta is an example of a color different from black. When the second toner cartridge 6M is installed in the device body 2, an image is formed using the magenta second toner TM. The second toner information is stored in the toner memory 65M of the second toner cartridge 6M.

[0067] The second toner information includes the value of the second charging bias voltage Vg2 and the value of the second developing bias voltage Vb2.

[0068] The value of the second charging bias voltage Vg2 is the optimal charging bias voltage value when forming an image of the magenta second pigment TM. The optimal charging bias voltage value when forming an image of the magenta second pigment TM differs from the optimal charging bias voltage value when forming an image of the black second pigment TM. For example, the value of the second charging bias voltage Vg2 is 950V.

[0069] The second development bias voltage Vb2 is the optimal development bias voltage for image formation of the magenta second toner TM. The optimal development bias voltage for image formation of the magenta second toner TM differs from the optimal development bias voltage for image formation of the black second toner TM. For example, the value of the second development bias voltage Vb2 is 200V.

[0070] like Figure 3 As shown, the image forming apparatus 1 also includes a control unit 100, a main memory 110, and a bias voltage application circuit 120.

[0071] The control unit 100 includes a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), and input / output circuitry. It performs various calculations based on programs and data stored in the ROM and other memory to control the image forming apparatus 1. The control unit 100 can read and write data to the main memory 110, the drum memory 57, and the toner memory 65.

[0072] The main memory 110 is a memory configured within the main body 2 of the device.

[0073] The bias application circuit 120 can apply bias voltage to the charger 53, transfer roller 54, cleaning roller 55, secondary cleaning roller 56, and developing roller 62. In this embodiment, the charger 53 is a gate-controlled corona discharge (GCD) charger. The charger 53 has a charging cable 53A and a gate electrode 53B.

[0074] The bias application circuit 120 applies a positive bias voltage to the developing roller 62.

[0075] The bias application circuit 120 applies a charging bias voltage to the charger 53 by applying a voltage to the charging line 53A. The bias application circuit 120 controls the voltage applied to the charging line 53A so that the voltage of the gate electrode 53B becomes the target charging bias voltage.

[0076] During image formation, the bias voltage application circuit 120 applies a negative bias voltage to the transfer roller 54. Conversely, during residual toner recovery, the bias voltage application circuit 120 applies a positive bias voltage to the transfer roller 54.

[0077] During image formation, the bias application circuit 120 applies a positive cleaning bias voltage to the cleaning roller 55, the absolute value of which is smaller than the charging bias voltage. The surface potential of the cleaning roller 55 is higher than the voltage of the exposed portion of the photosensitive drum 52. Therefore, the cleaning roller 55 electrostatically attracts and recovers negatively charged paper dust attached to the photosensitive drum 52, but does not recover toner remaining in the exposed portion of the photosensitive drum 52.

[0078] The bias application circuit 120 applies a positive bias voltage to the secondary cleaning roller 56. The positive bias voltage applied to the secondary cleaning roller 56 has an absolute value greater than the bias voltage applied to the cleaning roller 55. As a result, the secondary cleaning roller 56 electrostatically recovers the paper dust recovered by the cleaning roller 55.

[0079] Next, the actions performed by the control unit 100 during image formation in the first embodiment will be described.

[0080] When image formation is performed with the first toner cartridge 6B installed in the device body 2, the control unit 100 controls the bias voltage application circuit 120 based on the first toner information read from the toner memory 65.

[0081] Specifically, when the first toner cartridge 6B is installed, the control unit 100 applies a first charging bias voltage Vg1 to the charger 53 and a first developing bias voltage Vb1 to the developing roller 62. Furthermore, the first charging bias voltage Vg1 and the first developing bias voltage Vb1 vary depending on the specifications of the image forming apparatus 1 and the type of toner, and are predetermined values ​​based on the results of printing tests.

[0082] Furthermore, when image formation is performed with the first toner cartridge 6B installed on the main body 2 of the device, the control unit 100 displays black, which is the color of the toner, on the display unit 22 based on the first toner information.

[0083] When image formation is performed with the second toner cartridge 6M installed on the main body 2, the control unit 100 controls the bias voltage application circuit 120 based on the second toner information read from the toner memory 65.

[0084] Specifically, with the second toner cartridge 6M installed, the control unit 100 applies a second charging bias voltage Vg2 to the charger 53 and a second developing bias voltage Vb2 to the developing roller 62. In this embodiment, the second charging bias voltage Vg2 is different from the first charging bias voltage Vg1, and the second developing bias voltage Vb2 is different from the first developing bias voltage Vb1. Furthermore, the second charging bias voltage Vg2 and the second developing bias voltage Vb2 vary depending on the specifications of the image forming apparatus 1 and the type of toner, and are predetermined values ​​based on the results of printing tests.

[0085] Furthermore, when image formation is performed with the second toner cartridge 6M installed on the main body 2 of the device, the control unit 100 displays magenta, which is the color of the toner, on the display unit 22 based on the second toner information.

[0086] When image formation is performed with the first toner cartridge 6B or the second toner cartridge 6M installed, the control unit 100 applies a positive cleaning bias to the cleaning roller 55.

[0087] When image formation is performed with the first toner cartridge 6B or the second toner cartridge 6M installed, the control unit 100 applies a bias voltage with a positive polarity greater than that of the cleaning roller 55 to the secondary cleaning roller 56.

[0088] The control unit 100 stores the usage history of image formation using the first toner cartridge 6B and the usage history of image formation using the second toner cartridge 6M in the drum memory 57. The image formation history includes, for example, the cumulative number of printed sheets and the cumulative number of rotations of the developing roller 62.

[0089] Next, according to Figure 4 The flowchart shown illustrates an example of the operation performed by the control unit 100 in the first embodiment.

[0090] like Figure 4 As shown, when the control unit 100 determines that the power supply of the image forming apparatus 1 is turned on or the front cover 21 is closed (S11, Yes), since there is a possibility of replacing the toner cartridge 6, it reads toner information from the toner memory 65 (S12).

[0091] After step S12, the control unit 100 applies a bias voltage with the charging bias voltage value contained in the toner information (S13).

[0092] For example, when a first toner cartridge 6B containing a first black toner TB is installed, 850V is stored in the first toner information as a first charging bias voltage Vg1. Therefore, the control unit 100 applies the first charging bias voltage Vg1 of 850V to the charger 53.

[0093] Furthermore, when a second toner cartridge 6M containing a magenta second toner TM is installed, 950V is stored in the second toner information as a second charging bias voltage Vg2. Therefore, the control unit 100 applies the second charging bias voltage Vg2 of 950V to the charger 53.

[0094] After step S13, the control unit 100 applies a bias voltage with the development bias voltage value contained in the toner information (S14).

[0095] For example, when a first toner cartridge 6B containing a first black toner TB is installed, 300V is stored in the first toner information as a first developing bias voltage Vb1. Therefore, the control unit 100 applies the first developing bias voltage Vb1 of 300V to the developing roller 62.

[0096] Furthermore, when a second toner cartridge 6M containing a magenta second toner TM is installed, 200V is stored in the second toner information as a second developing bias voltage Vb2. Therefore, the control unit 100 applies a second developing bias voltage Vb2 of 200V to the developing roller 62.

[0097] After step S14, the control unit 100 displays the color of the pigment on the display unit 22 based on the pigment information (S15).

[0098] For example, if a first toner cartridge 6B containing a black first toner TB is installed, and the toner information is stored as black, the control unit 100 displays the toner as black on the display unit 22.

[0099] Furthermore, when a second toner cartridge 6M containing a magenta second toner TM is installed, the second toner information stores the case where the toner is magenta. Therefore, the control unit 100 displays the case where the toner is magenta on the display unit 22.

[0100] The following effects can be obtained from the image forming apparatus 1.

[0101] When the first toner cartridge 6B is installed, the control unit 100 applies a first developing bias voltage Vb1 to the developing roller 62 based on the first toner information stored in the toner memory 65. Furthermore, when the second toner cartridge 6M is installed, the control unit 100 applies a second developing bias voltage Vb2 based on the second toner information stored in the toner memory 65. Therefore, when black and toner cartridges of different colors (e.g., black and different toners) are installed, images can be formed at appropriate concentrations, respectively.

[0102] Furthermore, in the image forming apparatus 1, the toner cartridge 6 is mounted on the apparatus body 2 in a state where it is mounted on the drum cartridge 5. Therefore, compared to the case where the drum cartridge 5 and the toner cartridge 6 are mounted separately on the apparatus body 2, it is easier to mount them on the apparatus body 2.

[0103] Furthermore, when the first toner cartridge 6B is installed, the control unit 100 applies a first charging bias voltage Vg1 to the charger 53. Furthermore, when the second toner cartridge 6M is installed, the control unit 100 applies a second charging bias voltage Vg2. Therefore, it is possible to form images at appropriate concentrations for toner cartridges 6 that are black and toner cartridges of colors different from black.

[0104] In addition, the first toner information includes the value of the first developing bias voltage Vb1, and the second toner information includes the value of the second developing bias voltage Vb2, thereby enabling the control unit 100 to apply an appropriate developing bias voltage corresponding to the first toner TB and the second toner TM.

[0105] Furthermore, the control unit 100 displays the color of the toner contained in the toner cartridge 6 installed in the device body 2 on the display unit 22. Therefore, the color of the toner in the toner cartridge 6 installed in the device body 2 is easy to understand.

[0106] Furthermore, when image formation is performed with the first toner cartridge 6B or the second toner cartridge 6M installed, the control unit 100 applies a positive cleaning bias to the cleaning roller 55. Therefore, paper dust with a negative charge is recovered by the cleaning roller 55, while residual toner with a positive charge is not recovered by the cleaning roller 55 and can thus be recycled back into the toner storage chamber 61.

[0107] Furthermore, the control unit 100 applies a positive bias voltage to the secondary cleaning roller 56 that is greater than that to the cleaning roller 55. Therefore, the paper dust adhering to the cleaning roller 55 can be effectively recovered using the secondary cleaning roller 56.

[0108] Furthermore, the control unit 100 stores the usage history of image formation using the first toner cartridge 6B and the usage history of image formation using the second toner cartridge 6M in the drum memory 57. Therefore, the control of image formation can be appropriately modified by referring to the usage history of the first toner cartridge 6B and the usage history of the second toner cartridge 6M. For example, when the second toner cartridge 6M is installed in the drum cassette 5, if there is a usage history of the first toner cartridge 6B being used recently, the control unit 100 extends the preparation rotation time of the photosensitive drum 52 and the developing roller 62 before printing, thereby enabling the recovery of the first toner TB remaining on the photosensitive drum 52 using the second toner cartridge 6M.

[0109] Next, the second embodiment will be described.

[0110] In the first embodiment, the first toner information and the second toner information include the value of the bias voltage. In contrast, the second embodiment differs from the first embodiment in that the first toner information and the second toner information include deviation values ​​relative to the reference bias voltage, rather than including the bias voltage value itself as the first toner information or the second toner information.

[0111] In the second embodiment, the values ​​of the reference charging bias voltage and the reference developing bias voltage during image formation are stored in the main memory 110. As an example, the reference charging bias voltage is 850V and the reference developing bias voltage is 300V.

[0112] The first toner information includes deviations from a reference charging bias voltage and deviations from a reference developing bias voltage. For example, the deviation of the first toner information from both the reference charging bias voltage and the reference developing bias voltage is 0V.

[0113] The second toner information includes deviations from the reference charging bias voltage and deviations from the reference developing bias voltage. For example, the deviation of the second toner information from the reference charging bias voltage is +100V, and the deviation from the reference developing bias voltage is -100V.

[0114] With the first toner cartridge 6B installed, the control unit 100 applies a first charging bias voltage Vg1 (=850V+0V) to the charger 53 by an amount that deviates from the reference charging bias voltage (850V) by a deviation value (0V). Additionally, with the first toner cartridge 6B installed, the control unit 100 applies a developing bias voltage Vb (=300V+0V) to the developing roller 62 by an amount that deviates from the reference developing bias voltage (300V) by a deviation value (0V). In this embodiment, since the deviation value between the charging bias voltage and the developing bias voltage of the first toner cartridge 6B is 0V, the reference charging bias voltage and the reference developing bias voltage are directly applied.

[0115] With the second toner cartridge 6M installed, the control unit 100 applies a charging bias voltage Vg (=850V+100V) to the charger 53 by an amount that deviates from the reference charging bias voltage (850V) by a deviation value (+100V). Additionally, with the second toner cartridge 6M installed, the control unit 100 applies a developing bias voltage Vb (=300V-100V) to the developing roller 62 by an amount that deviates from the reference developing bias voltage (300V) by a deviation value (-100V).

[0116] Next, according to Figure 5 The flowchart shown illustrates an example of the actions performed by the control unit 100 in the second embodiment. Only steps that differ from those in the first embodiment are described; steps identical to those in the first embodiment are omitted.

[0117] like Figure 5 As shown, after step S12, the control unit 100 calculates the charging bias voltage that deviates from the reference charging bias voltage based on the toner information, and applies the calculated charging bias voltage (S23).

[0118] After step S23, the control unit 100 calculates the developing bias Vb that deviates from the reference developing bias based on the toner information, and applies the calculated developing bias (S24).

[0119] In the second embodiment described above, the first toner information includes the deviation value of the first developing bias voltage Vb1 relative to the reference developing bias voltage, thereby enabling the application of an appropriate developing bias voltage Vb value corresponding to the first toner TB. Additionally, the second toner information includes the deviation value of the second developing bias voltage Vb2 relative to the reference developing bias voltage, thereby enabling the application of an appropriate developing bias voltage Vb value corresponding to the second toner TM.

[0120] The embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments. Appropriate modifications can be made to the specific structure without departing from the spirit of the present invention.

[0121] In the above embodiments, magenta is shown as an example of a color different from black, but there is no particular limitation on the color different from black, and it can also be yellow, cyan, red, blue, light blue, green, brown, gray, etc.

[0122] In the above embodiment, the pigment is positively polarized, but it can also be negatively polarized. When using negatively polarized pigment, the bias voltage application circuit 120 only needs to apply a bias voltage of the opposite polarity to that used when positively polarized pigment is used.

[0123] In the above embodiments, the toner cartridge 6 can be installed in the device body 2 in the state of being installed in the drum cartridge 5, but the toner cartridge 6 and the drum cartridge 5 can also be installed separately in the device body 2.

[0124] In the above embodiments, the toner cartridge 6 can be installed in the device body 2 in the state of being installed in the drum cartridge 5, but the processing cartridge having a toner receiving chamber, developing roller, photosensitive drum and toner memory can also be a structure that can be installed in the device body 2.

[0125] For example, the main body of the device can be equipped with only either the first processing box or the second processing box.

[0126] The first processing cartridge is a cartridge containing black first toner. When the first processing cartridge is mounted on the main body of the device, an image is formed using the black first toner. The first toner information is stored in the toner memory of the first processing cartridge.

[0127] The second processing cartridge is a cartridge that holds a second color toner of a color different from black. When the second processing cartridge is installed on the main body of the device, an image is formed using the second color toner of a color other than black. The second color toner information is stored in the toner memory of the second processing cartridge.

[0128] When image formation is performed with the first processing box installed, the control unit applies a first developing bias voltage to the developing roller based on the first toner information.

[0129] When image formation is performed with the second processing cartridge installed, the control unit applies a second developing bias to the developing roller based on the second toner information.

[0130] In this method, when a first processing cartridge is installed, the control unit applies a first developing bias voltage to the developing roller based on the first toner information stored in the toner memory. When a second processing cartridge is installed, the control unit applies a second developing bias voltage based on the second toner information stored in the toner memory. Therefore, when processing cartridges of black and colors different from black are installed, images can be formed at appropriate concentrations respectively.

[0131] In the above embodiments, an example is shown where the second charging bias voltage Vg2 is different from the first charging bias voltage Vg1, and the second developing bias voltage Vb2 is different from the first developing bias voltage Vb1. However, it is also possible that the second charging bias voltage Vg2 is the same as the first charging bias voltage Vg1, and the second developing bias voltage Vb2 is different from the first developing bias voltage Vb1. Alternatively, it is also possible that the second charging bias voltage Vg2 is different from the first charging bias voltage Vg1, and the second developing bias voltage Vb2 is the same as the first developing bias voltage Vb1.

[0132] In the above embodiment, the control unit 100 stores the usage history of image formation using the first toner cartridge 6B and the usage history of image formation using the second toner cartridge 6M in the drum memory 57, but it may also store the usage history of the first toner cartridge 6B and the usage history of the second toner cartridge 6M in the main memory 110.

[0133] In the above embodiments, the present invention is applied to image forming apparatus 1, but the present invention is not limited thereto, and can also be applied to other image forming apparatuses, such as copiers, multifunction printers, etc.

[0134] The elements described in the above embodiments and variations can also be combined in any way.

[0135] [Example]

[0136] Next, refer to Figure 6 , Figure 7The table describes different embodiments that demonstrate the image formation quality when the toner color, charging bias voltage Vg, and developing bias voltage Vb are changed in toner cartridge 6.

[0137] [Example 1]

[0138] In Example 1, in the Type A image forming apparatus, the charging bias voltage and developing bias voltage Vb of black and magenta toners were appropriately changed respectively to confirm the image formation quality. The Type A image forming apparatus is an apparatus that performs image formation at a standard speed.

[0139] like Figure 6 As shown, in the image forming apparatus of type A, image forming is performed under seven conditions from 1 to 7, and the "density" and "ghosting" are visually observed to determine whether it is suitable for practical use.

[0140] "Concentration" refers to the concentration of toners used in image formation, with those falling within the standard range considered "appropriate".

[0141] "Ghosting" refers to toner adhering to unintended areas. Set "A" to no ghosting at all, "B" to almost none, "C" to slightly ghosting, "D" to slightly noticeable ghosting, and "E" to quite noticeable ghosting.

[0142] Taking into account "concentration" and "ghosting", multiple judges will determine whether it is suitable for practical use.

[0143] Condition 1 (black, Vg = 850V, Vb = 300V) is the optimal condition for black in a type A toner cartridge.

[0144] As in condition 2, if magenta is imaged with the same bias voltage as the optimal condition for black, the density becomes too high and the ghosting is quite noticeable, so it is deemed unsuitable for use.

[0145] As in condition 3, if the developing bias voltage Vb is set to half the value (150V) from the optimal black condition, the density will be slightly higher, but there will be almost no ghosting, and it will be deemed suitable for use.

[0146] As in condition 4, if the developing bias Vb is set to slightly more than half (200V) from the optimal black condition, the concentration becomes appropriate, there is almost no ghosting, and it is determined to be suitable for use.

[0147] As in condition 5, if the charging bias voltage Vg is increased by 100V (950V) and the developing bias voltage Vb is decreased by 50V (250V) from the optimal black condition, the concentration is appropriate, but ghosting occurs, and it is determined that it is not suitable for use.

[0148] As in condition 6, if the charging bias voltage Vg is increased by 100V (950V) and the developing bias voltage Vb is decreased by 100V (200V) from the optimal black condition, the concentration is appropriate, there is no ghosting at all, and it is determined to be the most suitable for use.

[0149] As in condition 7, if the charging bias voltage Vg is increased by 150V (1000V) from the optimal condition of black, the concentration will be high and the ghosting will be prominent, so it is determined that it is not suitable for use.

[0150] Based on the above results, it was confirmed that in the type A image forming apparatus, when forming an image of magenta toner, the conditions of charging bias voltage Vg being +100V and developing bias voltage Vb being -100V are optimal compared to the conditions for forming an image of black toner.

[0151] [Example 2]

[0152] In Example 2, in the Type B image forming apparatus, the charging bias voltage and developing bias voltage Vb of the black and magenta toners were appropriately changed respectively, and the image formation quality was confirmed. The Type B image forming apparatus is an image forming apparatus that performs image formation at 1.5 times the speed of the Type A image forming apparatus.

[0153] like Figure 7 As shown, in the image forming apparatus of type B, image forming is performed under three conditions 8 to 10. As in Example 1, the "density" and "ghosting" are visually observed to determine whether it is suitable for practical use.

[0154] Condition 8 (black, Vg = 850V, Vb = 400V) is the optimal condition for black in a type B toner cartridge.

[0155] As in condition 9, if magenta is imaged with the same bias voltage as the optimal condition for black, the concentration becomes too light and it is deemed unsuitable for use.

[0156] As in condition 10, if the developing bias voltage Vb is increased by 100V (500V) from the optimal black condition, the concentration is appropriate, there is no ghosting at all, and it is determined to be the most suitable for use.

[0157] Based on the above results, it was confirmed that in the type B image forming apparatus, when forming an image of magenta toner, the developing bias voltage Vb of +100V is optimal compared to the conditions for forming an image of black toner.

Claims

1. An image forming apparatus, characterized in that, have: A toner cartridge having a toner receiving chamber, a developing roller, and a toner storage device; Drum box, which contains a photosensitive drum; The main body of the device is capable of housing the toner cartridge and the drum cartridge; A bias voltage application circuit that is capable of applying a bias voltage; as well as Control Department The control unit controls the bias voltage application circuit. When image formation is performed with the first toner cartridge installed (serving as the toner cartridge), a first developing bias is applied to the developing roller based on the first toner information. The first toner cartridge contains black first toner in the toner receiving chamber and stores the first toner information in the toner memory. This first toner information is information about the first toner. When image formation is performed with the second toner cartridge installed as the toner cartridge, a second developing bias voltage different from the first developing bias voltage is applied to the developing roller based on the second toner information. The second toner cartridge contains a second toner of a different color than black in the toner receiving chamber and stores the second toner information in the toner memory. This second toner information is the information of the second toner.

2. The image forming apparatus according to claim 1, characterized in that, The main body of the device can be equipped with either the first toner cartridge or the second toner cartridge.

3. The image forming apparatus according to claim 1, characterized in that, The drum housing can accommodate the toner cartridge. The main body of the device can be equipped with the toner cartridge installed in the drum box.

4. The image forming apparatus according to claim 1, characterized in that, The drum housing includes a charger for charging the photosensitive drum. The control unit controls the bias voltage application circuit. When image formation is performed with the first toner cartridge installed, a first charging bias voltage is applied to the charger based on the first toner information. When image formation is performed with the second toner cartridge installed, a second charging bias voltage, different from the first charging bias voltage, is applied to the charger based on the second toner information.

5. The image forming apparatus according to claim 1, characterized in that, The first toner information includes the value of the first development bias voltage. The second toner information includes the value of the second developing bias voltage.

6. The image forming apparatus according to claim 1, characterized in that, It also has a main memory that stores the value of the reference development bias voltage. The second toner information includes the deviation of the second developing bias relative to the reference developing bias.

7. The image forming apparatus according to claim 1, characterized in that, The main body of the device has a display unit for displaying information. The control unit displays the color of the toner contained in the installed toner cartridge on the display unit based on the first toner information or the second toner information read from the toner memory.

8. The image forming apparatus according to claim 1, characterized in that, The drum housing has a cleaning roller that contacts and rotates on the outer peripheral surface of the photosensitive drum. The first and second pigments are positively polar pigments. When image formation is performed with the first toner cartridge or the second toner cartridge installed, the control unit applies a positive cleaning bias to the cleaning roller.

9. The image forming apparatus according to claim 8, characterized in that, The drum housing has a secondary cleaning roller that contacts and rotates with the outer peripheral surface of the cleaning roller. The control unit controls the bias application circuit to apply a positive bias voltage to the secondary cleaning roller that is larger than that applied to the cleaning roller.

10. The image forming apparatus according to claim 1, characterized in that, The drum box also has a drum storage device. The control unit stores the usage history of image formation using the first toner cartridge and the usage history of image formation using the second toner cartridge in the drum memory.

11. An image forming apparatus, characterized in that, have: The processing cartridge includes a toner receiving chamber, a developing roller, a photosensitive drum, and a toner storage unit. The main body of the device is capable of housing the processing box; A bias voltage application circuit that is capable of applying a bias voltage; as well as Control Department The control unit controls the bias voltage application circuit. When image formation is performed with the first processing cartridge installed (serving as the processing cartridge), a first developing bias is applied to the developing roller based on first toner information. The first processing cartridge contains black first toner in the toner receiving chamber and stores the first toner information in the toner memory. This first toner information is information about the first toner. When image formation is performed with the second processing cartridge installed as the processing cartridge, a second developing bias voltage different from the first developing bias voltage is applied to the developing roller based on the second toner information. The second processing cartridge contains a second toner of a different color than black in the toner receiving chamber and stores the second toner information in the toner memory. The second toner information is the information of the second toner.

Images