JP2014211527A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus which acquires a set value for a device without increasing the size of a storage area or the number of addresses, even if the number of kinds of toner to be used in future is indefinite.SOLUTION: A set value to be changed for each kind of toner is stored in an external storage device 20. In a device constituting an image forming apparatus and using different set values for each kind of toner, when an imaging unit is replaced and change in toner kind is recognized while an address to be referred is fixed, an appropriate set value for the current toner is extracted from the external storage device 20 and input to the storage area of the reference address of the device.

Description

  The present invention relates to an image forming apparatus such as a copying machine, a printer, a facsimile machine, a plotter, and a multifunction machine provided with at least one of them.

Some recent color laser printers and color laser complex machines can use toners other than yellow (Y), magenta (M), cyan (C), and black (K) process colors.
One of them is a clear toner called transparent toner, colorless toner, achromatic toner, or no-pigment toner.
A user can generate printed matter with high added value by using clear toner effectively.

For example, there has been proposed an image forming apparatus that performs gloss adjustment by overlaying clear toner on a color printed matter (full surface printing or partial printing) (overall coating or partial coating).
In the entire surface coat or partial coat using clear toner, glossiness can be given to the entire sheet surface or a part of the sheet by printing the clear toner on the sheet surface after color printing.
At the same time, it can be used for the purpose of preventing color transfer due to friction of the image surface and protecting the image.

In this type of image forming apparatus, an image forming unit is independent for each color of process colors (Y, M, C, K), and can be exchanged for each color.
The image forming unit of special color material (toner) such as clear toner can also be replaced. By preparing and replacing multiple types of image forming units of special color material, you can obtain images of various colors and image quality. Can do.

When toner other than process colors is used by replacing the image forming unit, the setting value (storage address) of a device such as a fixing device differs for each type of toner, and the device needs to switch the address to be referred to.
For example, as shown in FIG. 13, in the image forming unit of the toner type 1, the device 1 constituting the image forming apparatus refers to the address a1 and obtains a set value.
When the image forming unit is replaced and the toner type 3 image forming unit is set, it is necessary to switch to the address a1 of the storage area of the toner type 3 as indicated by the dotted line.

In the method of providing storage addresses corresponding to the number of toner types in the storage area of the image forming apparatus main body, it is necessary to add the number of addresses when the toner types are added.
If the number of addresses increases, a device reference error may occur, and it may not be possible to change to an appropriate setting value.
Further, when the number of types of toner in the future is undecided, the size of the storage area is unknown, and the number of steps for correction and confirmation is large.

  The present invention was devised in view of such a current situation, and even when the number of types of toner to be used in the future is not yet determined, image formation that can acquire setting values of a device without increasing the size of the storage area and the number of addresses The main purpose is to provide the device.

  In order to achieve the above object, the present invention provides a plurality of image forming units for each toner color that form an electrostatic latent image on an image carrier and visualize the electrostatic latent image as a toner image by a developing device. An image forming apparatus in which the image forming unit can be replaced, wherein a setting value that needs to be changed for each type of toner is stored in an external storage unit, and constitutes the image forming apparatus, and includes a toner In the device using different setting values for each type, when the address to be referred to is fixed and the image forming unit is replaced and the change of the toner type is recognized, the external storage unit applies the change to the replaced toner. An appropriate set value is extracted and input to the address.

  According to the present invention, in the configuration in which the type of toner is changed by exchanging the image forming unit, problems due to an increase in the size of the storage area and the number of addresses referred to by the device can be solved.

1 is a schematic configuration diagram of an image forming apparatus according to an embodiment of the present invention. It is a control block diagram. It is an enlarged view of an image forming unit. FIG. 10 is a diagram for describing rewriting of setting values when a toner type is changed in a state where addresses referred to by devices constituting the image forming apparatus are fixed. FIG. 6 is a characteristic diagram showing the relationship between the number of white spots as an abnormal image and the development potential. It is a characteristic view which shows the relationship between the number of vitiligo spots, and background potential. It is a characteristic view which shows the relationship between a charging failure stripe rank and a number of sheets. FIG. 6 is a characteristic diagram showing a relationship between a transferability rank and a primary transfer current. FIG. 6 is a characteristic diagram showing a relationship between a transferability rank and a secondary transfer current. It is a characteristic view showing the relationship between the photoreceptor foreign matter adhesion rank and the lubricant (lubricant) consumption. FIG. 6 is a characteristic diagram illustrating a relationship between an offset rank at which toner adheres to a fixing roller and a fixing temperature. FIG. 6 is a characteristic diagram showing a relationship between an offset rank and a linear velocity (image forming velocity). FIG. 10 is a diagram illustrating switching of a storage area and an address referred to by a device in a conventional image forming apparatus.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
First, the overall configuration of the image forming apparatus according to the present embodiment and the configuration of the control unit will be described with reference to FIGS. 1 and 2.
The image forming apparatus 1 forms an image by fixing a toner image on a sheet as an example of a recording medium.
As shown in FIG. 1, the image forming apparatus 1 includes a control unit 10, an image reading unit 11, an image forming unit 12, a paper feeding unit 13, a transfer unit 14, a fixing unit 15, a paper discharge unit 16, and a display / operation unit. 17 etc.

As illustrated in FIG. 2, the control unit 10 includes a CPU (Central Processing Unit) 1011, a main memory (MEM-P) 1012, and a north bridge (NB) 1013.
Further, the control unit 10 includes a south bridge (SB) 1014 and an AGP (Accelerated Graphics Port) bus 1015.
In addition, the control unit 10 includes an application specific integrated circuit (ASIC) 1016, a local memory (MEM-C) 1017, and a hard disk (HD) 1018.
The control unit 10 includes an HDD (Hard Disk Drive) 1019 and a network I / F 102.

The CPU 1011 processes and calculates data according to a program stored in the main memory 1012, and operates the image reading unit 11, the image forming unit 12, the paper feeding unit 13, the transfer unit 14, the fixing unit 15, and the paper discharging unit 16. Or to control.
The main memory 1012 is a storage area of the control unit 10, and includes a ROM (Read Only Memory) 1012a and a RAM (Random Access Memory) 1012b.
The ROM 1012a is a memory for storing programs and data for realizing the functions of the control unit 10.
The program stored in the ROM 1012a is recorded in a computer-readable recording medium such as a CD-ROM, FD, CD-R, or DVD as a file in an installable or executable format and provided. May be.
The RAM 1012b is used as a memory for drawing during development of programs and data and memory printing.

The NB 1013 is a bridge for connecting the CPU 1011, the MEM-P 1012, the SB 1014, and the AGP bus 1015.
The SB 1014 is a bridge for connecting the NB 1013 to a PCI device and peripheral devices.
The AGP bus 1015 is a bus interface for a graphics accelerator card that has been proposed to speed up graphic processing.
The ASIC 1016 includes a PCI target, an AGP master, and an arbiter (ARB) that forms the core of the ASIC 1016.
The ASIC 1016 includes a memory controller that controls the MEM-C 1017, and a plurality of DMACs (Direct Memory Access Controllers) that rotate image data using hardware logic.

The ASIC 1016 is connected to a USB (Universal Serial Bus) interface via a PCI bus.
The ASIC 1016 is connected to an interface of IEEE 1394 (Institut of Electrical and Electronics Engineers 1394).
The MEM-C 1017 is a local memory used as a copy image buffer and a code buffer.

The HD 1018 is a storage for accumulating image data, accumulating font data used during printing, and accumulating forms.
The HDD 1019 controls reading or writing of data with respect to the HD 1018 according to the control of the CPU 1011.
The network I / F 102 transmits / receives information to / from an external device such as an information processing apparatus via a communication network.

The image reading unit 11 generates image information by optically reading an image written on a sheet.
Specifically, the image information is read by applying light to a sheet and receiving the reflected light by a reading sensor such as a CCD (Charge Coupled Devices) or a CIS (Contact Image Sensor).
The image information is information representing an image to be formed on a recording medium such as paper, and uses electrical color separation image signals indicating red (R), green (G), and blue (B) colors. It is shown.
As shown in FIG. 1, the image reading unit 11 includes a contact glass 111, a reading sensor 112, and the like.

The contact glass 111 is for placing a sheet on which an image is written.
The reading sensor 112 reads image information of an image described on a sheet placed on the contact glass 111.

The image forming unit 12 attaches toner to the surface of the intermediate transfer belt 143 of the transfer unit 14 based on the image information read by the image reading unit 11 or the image information received by the network I / F 102 to generate an image (toner Image).
The image forming unit 12 includes an image forming unit 120C that forms a toner image using a developer having cyan (C) color toner, and an image forming unit 120M that forms a toner image using magenta (M) toner. An image forming unit 120Y that forms a toner image using yellow (Y) toner, an image forming unit 120K that forms a toner image using black (K) toner, and a clear (T) toner. And an image forming unit 120T that forms a toner image using the same.
That is, the image forming unit 12 includes a plurality of image forming units as image forming units for each toner color.

  As will be described later, the image forming apparatus 1 develops (visualizes) the electrostatic latent image formed on each photosensitive drum with a corresponding color toner, and finally converts the toner image of each color into a recording medium. The image is transferred in a superimposed state.

Hereinafter, one or more of the C color toner, the M color toner, the Y color toner, and the K color toner is referred to as a colored toner.
The image forming unit using the clear toner is arranged so as to be positioned at the top of the toner image transfer order of each image forming unit including the image forming unit using the color toner.
Each colored toner is a resin particle having a charging property containing a coloring material such as a pigment or a dye.
Further, the clear toner is a colorless and transparent toner, and is a resin particle configured so that the colored toner can be visually recognized when attached to the colored toner attached to the recording medium.

The clear toner is resin particles that can be visually recognized when attached to the recording medium.
The clear toner is produced, for example, by externally adding silicon dioxide (SiO ₂ ) or titanium dioxide (TiO ₂ ) to a low molecular weight polyester resin.
Note that the clear toner may contain a coloring material as long as the amount is such that the recording medium or the colored toner attached on the recording medium can be visually recognized.

Hereinafter, an arbitrary image forming unit among the image forming unit 120C, the image forming unit 120M, the image forming unit 120Y, the image forming unit 120K, and the image forming unit 120T is referred to as an “image forming unit 120”.
The image forming unit 120C includes a toner supply unit 121C, a photosensitive drum (hereinafter also simply referred to as “photosensitive member”) 122C, a charging unit 123C, an exposure unit 124C, a developing unit 125C, a charge eliminating unit 126C, and a cleaning unit 127C. Yes.
The toner supply unit 121C stores C-color toner, and supplies C-color toner to the development unit 125C.
The toner stored in the toner supply unit 121C is supplied to the developing unit 125C by a predetermined amount by driving the conveying screw in the toner supply unit 121C.
The surface of the photosensitive drum 122C is uniformly charged by the charging unit 123C, and an electrostatic latent image is formed on the surface by the exposure unit 124C based on the image information received from the control unit 10.

On the surface of the photosensitive drum 122C, a toner image is formed by the developing unit 125C attaching toner to the surface on which the electrostatic latent image is formed.
The photosensitive drum 122C is provided so as to be in contact with the intermediate transfer belt 143, and is provided to rotate in the same direction as the moving direction of the intermediate transfer belt 143 at a contact point with the intermediate transfer belt 143.
The charging unit 123C uniformly charges the surface of the photosensitive drum 122C.
The exposure unit 124C irradiates the surface of the photosensitive drum 122C charged by the charging unit 123C with light based on the C halftone dot area ratio determined by the control unit 10 to form an electrostatic latent image.
The developing unit 125C develops the toner image by attaching the C-color toner stored in the developer storage unit 121C to the electrostatic latent image formed on the surface of the photosensitive drum 122C by the exposure unit 124C. Form.

The neutralization unit 126C neutralizes the surface of the photosensitive drum 122C after the image is transferred to the intermediate transfer belt 143.
The cleaning unit 127C removes the transfer residual toner remaining on the surface of the photosensitive drum 122C that has been neutralized by the neutralization unit 126C.

The image forming unit 120M includes a developer storage unit 121M, a photosensitive drum 122M, a charging unit 123M, an exposure unit 124M, a developing unit 125M, a charge removal unit 126M, and a cleaning unit 127M.
The developer storage unit 121M stores M-color toner.
The photosensitive drum 122M, the charging unit 123M, the exposure unit 124M, the development unit 125M, the charge removal unit 126M, and the cleaning unit 127M are the photosensitive drum 122C, the charge unit 123C, the exposure unit 124C, the development unit 125C, the discharge unit 126C, and the cleaning unit, respectively. Since the function is the same as that of 127C, the description thereof is omitted (the same applies to Y, K, and T).

The image forming unit 120Y includes a developer container 121Y, a photosensitive drum 122Y, a charging unit 123Y, an exposure unit 124Y, a developing unit 125Y, a charge removal unit 126Y, and a cleaning unit 127Y.
The developer storage unit 121Y stores Y toner.
The image forming unit 120K includes a developer container 121K, a photosensitive drum 122K, a charging unit 123K, an exposure unit 124K, a developing unit 125K, a charge removal unit 126K, and a cleaning unit 127K.
The developer storage unit 121K stores K-color toner.

The image forming unit 120T includes a developer container 121T, a photosensitive drum 122T, a charging unit 123T, an exposure unit 124T, a developing unit (developing device) 125T, a charge eliminating unit 126T, and a cleaning unit 127T.
The developer storage unit 121T stores clear toner.
Hereinafter, any developer accommodating portion among the developer accommodating portion 121C, the developer accommodating portion 121M, the developer accommodating portion 121Y, the developer accommodating portion 121K, and the developer accommodating portion 121T is referred to as “developer accommodating portion 121”. It expresses.
An arbitrary photosensitive drum among the photosensitive drum 122C, the photosensitive drum 122M, the photosensitive drum 122Y, the photosensitive drum 122K, and the photosensitive drum 122T is represented as “photosensitive drum 122”.
Any charging unit among the charging unit 123C, the charging unit 123M, the charging unit 123Y, the charging unit 123K, and the charging unit 123T is referred to as a “charging unit 123”.

An arbitrary exposure unit among the exposure unit 124C, the exposure unit 124M, the exposure unit 124Y, the exposure unit 124K, and the exposure unit 124T is referred to as an “exposure unit 124”.
An arbitrary developing unit among the developing unit 125C, the developing unit 125M, the developing unit 125Y, the developing unit 125K, and the developing unit 125T is represented as “developing unit 125”.
Any static elimination part among the static elimination part 126C, the static elimination part 126M, the static elimination part 126Y, the static elimination part 126K, and the static elimination part 126T is represented as "the static elimination part 126".
An arbitrary cleaning unit among the cleaning unit 127C, the cleaning unit 127M, the cleaning unit 127Y, the cleaning unit 127K, and the cleaning unit 127T is referred to as a “cleaning unit 127”.

The paper supply unit 13 supplies paper to the transfer unit 14. The paper feed unit 13 includes a paper storage unit 131, a paper feed roller 132, a paper feed belt 133, and a registration roller pair 134.
The paper storage unit 131 stores paper that is an example of a recording medium. The paper feed roller 132 is provided to rotate in order to move the paper stored in the paper storage unit 131 toward the paper supply belt.
The paper feed roller 132 provided in this way takes out the uppermost one of the stored paper one by one and places it on the paper feed belt.
The paper feed belt 133 conveys the paper taken out by the paper feed roller 132 to the transfer unit 14.
The registration roller pair 134 feeds out the sheet conveyed by the sheet feeding belt 133 at a timing when a portion where a toner image is formed on the intermediate transfer belt 143 described later reaches the transfer unit 14.

The transfer unit 14 transfers the image formed on the photosensitive drum 122 by the image forming unit 12 to the intermediate transfer belt 143 (primary transfer), and transfers the image transferred to the intermediate transfer belt 143 to the sheet (secondary transfer). )
The transfer unit 14 includes a drive roller 141, a driven roller 142, an intermediate transfer belt 143, primary transfer rollers 144C, 144M, 144Y, 144K, and 144T, a secondary transfer roller 145, and a secondary transfer counter roller 146.
The driving roller 141 spans the intermediate transfer belt 143 together with the driven roller 142.
As the driving roller 141 is driven and rotated, the intermediate transfer belt 143 that is being moved moves.

The intermediate transfer belt 143 moves while contacting the photosensitive drum 122 as the drive roller 141 rotates.
As the intermediate transfer belt 143 moves while being in contact with the photosensitive drum 122, the image formed on the photosensitive drum 122 is transferred to the surface of the intermediate transfer belt 143.

The primary transfer rollers 144C, 144M, 144Y, 144K, and 144T are arranged to face the photosensitive drums 122C, 122M, 122Y, 122K, and 122T, respectively, with the intermediate transfer belt 143 interposed therebetween.
The secondary transfer roller 145 rotates with the intermediate transfer belt 143 and the paper sandwiched between the secondary transfer counter roller 146.

The fixing unit 15 fixes the toner transferred to the sheet by the transfer unit 14.
Fixing refers to fusing the resin component of the toner to the paper by simultaneously applying heat and pressure to the toner.
By fixing the toner transferred to the paper by the transfer unit 14, the state of the toner on the paper becomes stable.
The fixing unit 15 includes a conveyance belt 151, a fixing belt 152, a fixing roller 153, a fixing belt conveyance roller 154, a fixing counter roller 155, and a heat generation unit 156.
The conveyance belt 151 conveys the sheet on which the toner is transferred by the transfer unit 14 toward the fixing roller 153 and the fixing counter roller 155.

The fixing belt 152 is stretched between the fixing roller 153 and the fixing belt conveying roller 154, and moves as the rollers rotate.
The fixing roller 153 sandwiches the sheet transported to the transport belt 151 between the fixing facing roller 155 disposed opposite to the sheet, and heats and pressurizes the sheet.
The fixing belt conveyance roller 154 hangs the fixing belt 152 together with the fixing roller 153, and moves the fixing belt 152 when the fixing belt conveyance roller 154 rotates.
The fixing facing roller 155 is installed facing the fixing roller 153, and sandwiches the conveyed paper between the fixing roller 153.
The heat generating unit 156 is installed inside the fixing roller 153 and generates heat, and heats the sheet via the fixing roller 153.

The paper discharge unit 16 discharges the paper on which the toner is fixed by the fixing unit 15 from the image forming apparatus 1, and includes a paper discharge belt 161, a paper discharge roller 162, a paper discharge port 163, and a paper storage unit 164. doing.
The paper discharge belt 161 conveys the paper fixed by the fixing unit 15 toward the paper discharge port 163.
The paper discharge roller 162 discharges the paper conveyed by the paper discharge belt 161 from the paper discharge port 163 and stores it in the paper storage unit 164. The paper storage unit 164 stores the paper discharged by the paper discharge roller 162.

The display / operation unit 17 includes a panel display unit 171 and an operation unit 172.
The panel display unit 171 displays setting values and selection screens. The panel display unit 171 is a touch panel or the like that receives input from the operator.
The operation unit 172 is operated by a user for input such as a numeric keypad for receiving various conditions relating to image formation and a start key for receiving a copy start instruction.

FIG. 3 is a schematic view of the image forming unit (process cartridge) of FIG.
The process cartridge is a unit in which at least one of a cleaning unit (cleaning unit), a charging unit (charging unit), and a developing unit (developing unit) is integrated with the photosensitive member.
The charging unit 123 includes a charging roller 123a, a charging cleaner roller 123b, and a pressure spring that pressurizes them.

The surface of the photoconductor 122 is uniformly charged by the charging roller 123a.
As charging means, there are a scorotron system, a corotron system, a contact roller charging system using a medium resistance rubber roller, and a non-contact roller charging system, which are charging by a wire.
In this embodiment, a non-contact charging roller charging method is adopted.

The Scorotron method was previously used to charge the surface of a photoconductor to (-). However, ozone is generated during discharge, so from the viewpoint of placing importance on the environment, there are currently limited models. Used only in groups.
The corotron method charges the photosensitive member to (+) and generates less ozone, but is not commonly used.
Recently, since the unit price of a charging roller capable of suppressing the generation of ozone has been reduced, the roller charging method is the most common charging means.
For both the contact roller charging method and the non-contact roller charging method, there are a method of superimposing alternating current on direct current and a method of applying only direct current.

When alternating current is superimposed on direct current, high image quality can be obtained compared to direct current, but attention must be paid to the problem of photoconductor filming.
In addition, the constant current control of alternating current has the advantage that the surface potential is not affected by fluctuations in the resistance value of the charging roller due to environmental changes, but the cost of the high-voltage power supply increases and the sound of alternating high frequency is a problem. It is as.
When only a direct current is applied, a change in the resistance value of the charging roller due to the environmental change affects the surface potential with respect to the environmental change, and thus some means for correcting the applied voltage is required.

In the case of non-contact, if alternating current is controlled at a constant current, the image will be uneven due to the effect of gap fluctuation between the photoconductor and the charging roller. Therefore, the applied voltage is corrected in the same way as when only direct current is applied. Means are needed.
However, since it is non-contact, there is more room for contamination of the charging roller than the contact type.
As a correction method, there are a method of detecting the temperature in the vicinity of the charging roller and switching the applied voltage, a method of periodically detecting ground contamination on the photosensitive member and switching the applied voltage, and a method of determining the applied voltage based on a feedback current value. is there.
By taking these methods, the surface of the photoreceptor is charged to about -500V to -700V.

As a driving method, there are a method in which the photosensitive member is pressed against the photosensitive member and rotated by a frictional force, and a method in which a driving force is obtained from a photosensitive member gear or the like.
In the case of a low speed machine, the former method is often used, but in the machine that requires high speed and high image quality, the latter method is often used.

When the surface of the charging roller becomes dirty, the charging ability of the portion where the dirt is attached is reduced, and the photosensitive member cannot be charged to the target potential.
As a result, an abnormal image of defective charging appears.
In order to prevent this, a charging roller cleaner (cleaning roller) 123b is brought into contact.
The charging roller cleaner 123b includes a flocking roller in which fibers are electrostatically flocked on a metal shaft, and a melamine roller in which a melamine resin is disposed on the roller around the metal shaft. In most cases, a roller is used.
If slip occurs between the cleaning roller and the charging roller, the dirt is rubbed against the surface of the charging roller, and the generation of an abnormal image due to the dirt is accelerated.

With respect to the charging roller cleaner, the surface of the charging roller is removed by moving around the charging roller without being driven.
When the drive is applied, a slipping state is inevitably caused by the tolerance of the charging roller diameter and the diameter tolerance of the charging roller cleaner, and the life is shortened.
Ideally, it is desirable that the surface moving speed is the same at the contact portion between the charging roller and the cleaning roller without slipping.

In FIG. 3, symbol Lb indicates exposure light from the exposure unit 124.
In FIG. 3, the static elimination unit 126 is omitted.

The cleaning unit 127 includes a cleaning blade 127a, a waste toner collecting coil 127b, and the like.
The cleaning blade 127a is made of urethane rubber and is in contact with the surface of the photoreceptor in the counter direction.
The most commonly used method (cleaning blade method) is to scrape the residual toner after transfer at the edge of the cleaning blade 127a.
The toner scraped off by the cleaning blade is transported forward or rearward in the figure by a waste toner collecting coil and stored in a waste toner tank (not shown).
In color copiers, there is a problem of color mixing of waste toner, and generally it is not reused.

In order to protect the surface of the photosensitive member, a photosensitive member protective agent (lubricant) as an image carrier protecting agent may be applied to the photosensitive member surface.
This is performed to prevent photoconductor filming, to secure a cleaning function, to protect the photoconductor surface from charging AC, and to prevent wear of the photoconductor.
A protective agent coating device 128 as a protective agent supply device is provided downstream of the cleaning unit 127 in the moving direction of the photosensitive member (not shown in FIG. 1).
The protective agent application device 128 includes a lubricant 128a as an image carrier protective agent, a brush roller 128b as a lubricant supply means for applying the lubricant 128a on the photosensitive member, and a lubrication for pressing the lubricant 128a toward the brush roller 128b. A pressurizing spring 128c as an agent pressurizing member is provided.

The photoconductor protective agent is in pressure contact with the brush roller, and is gradually scraped by the rotation of the brush roller, and the shaved protective agent is applied to the surface of the photoconductor.
The lubricant applied on the photoreceptor is stretched into a thin layer by the application blade 129 disposed on the downstream side, and is fixed on the photoreceptor surface with a uniform thickness.

As the protective agent application means, a brush roller is most often used, and as the material, insulating PET, conductive PET, acrylic fiber, or the like is used.
In particular, conductive fibers are often used in order to avoid abnormal images due to the effect of frictional charging by the brush roller and the photoconductor.
Lubricant pressurization means include compression springs, weights, tension springs and cams, but compression springs are most often used in terms of balance of function, space, and cost. ing.
The photoconductor protective agent mainly contains a fatty acid metal salt and an inorganic lubricant. Depending on the amount of inorganic lubricant added, inorganic fine particles may be contained.

Hereinafter, application amount (supply amount) control by the protective agent application device 128 will be described.
Solid lubricants include a pressure molding type lubricant in which a powdery lubricant (= protective agent) is press-molded as it is, and a melting type lubricant formed by heating and melting once and then cooling.
The hardness of the lubricant differs depending on the molding method of the lubricant, and when the constituent materials of the lubricant are the same, the melt type lubricant tends to be harder to scrape the lubricant.
The ability to scrape the lubricant is determined by the hardness of the lubricant and the shaving ability of the application means.
For example, when a lubricant supply brush (brush roller) is used as the application means, the lubricant shaving capability is determined by the brush characteristic values such as the fiber length, thickness, density and material of the lubricant supply brush, and the lubricant supply brush. It depends on the number of rotations.

In the following, an example in which a pressure forming type lubricant and a lubricant supply brush are used as the lubricant supply means will be described.
As a method for controlling the application amount of the lubricant, there are a method for controlling the pressure applied by the pressure spring shown in FIG. 3, a method for changing the rotation speed of the brush roller, a method for changing the hardness of the lubricant, and the like.
When the application amount is controlled by the pressure applied by the pressure spring, the pressure can be controlled mechanically or magnetically by a solenoid magnet, although not shown.
In the case where the coating amount is controlled by the hardness of the lubricant, for example, at the time of pressure forming of the lubricant, if the pressing force is increased and the density of the lubricant is increased, the lubricant becomes hard and difficult to be scraped.
On the other hand, if the density of the lubricant is lowered, the lubricant becomes soft, and therefore it is easy to scrape.

When the application amount is controlled by the number of rotations of the brush roller, it is performed by changing the number of rotations of a motor (not shown).
When the number of rotations of the brush roller is decreased, the amount of lubricant applied decreases, and when the number of rotations is increased, the amount of application increases.

Based on FIG. 4, switching of setting values when the image forming unit is replaced (change of toner type) will be described. Hereinafter, the toner type is also referred to as “toner type”.
In this embodiment, in addition to the process colors Y, M, C, and K, four types of special color materials (toners) of toner type 1, toner type 2, toner type 3, and toner type 4 can be used. .
That is, the four types of special color material imaging units are prepared.
For example, a case will be described in which the toner of the image forming unit 120T is the toner type 1, and this is removed and replaced (replaced) with the image forming unit 120 using the special color toner of the toner type 3.

After the replacement, the user selects the toner type 3 on the setting screen of the panel display unit 171.
The main memory of the control unit 10 of the image forming apparatus 1 has one storage area, and the device 1 (here, referred to as a fixing unit) obtains a set value with reference to the address a1.
The device 2 (here, the developing unit) obtains the set value with reference to the address a2.
The device 3 (here, a charging unit) obtains the set value with reference to the address a3.

The image forming apparatus 1 includes an external storage device (SD card) 20 as an external storage unit, and the external storage device 20 stores all setting values for each toner type.
The reference numeral 1 indicates the setting value of the toner type 1, the reference numeral 2 indicates the setting value of the toner type 2, the reference numeral 3 indicates the setting value of the toner type 3, and the reference numeral 4 indicates the setting value of the toner type 4. .
When the set value differs for each toner type, for example, the value (set value) of the storage area referred to by the fixing device (fixing unit) with respect to the fixing temperature needs to be changed.

As described above, after replacing the image forming unit 120 using the special color toner of the toner type 3, the user selects the toner type 3 on the setting screen of the panel display unit 171.
When it is detected (recognized) that the image forming unit has been replaced by a unit detecting unit (not shown), the control unit 10 (substantially the CPU) accesses the external storage device 20 to access the main image forming apparatus. The set value data in the storage area of the memory is rewritten with toner type 3 data.
That is, the set value for the toner type 3 is extracted from the external storage device 20 and input to the storage area of each address.
The recording area of the main memory of the image forming apparatus is one, and a device using a different value (setting value) for each toner type has a fixed address to be referred to.

As described above, in the “method of changing the value from the outside” of the present embodiment, only one storage area is required, and it is not necessary to change the address referred to by the device. Can be changed.
Since only one storage area is required, it is not necessary to change the size of the storage area of the image forming apparatus even when the number of toner types to be used in the future is undetermined.
The external storage device 20 is a storage medium such as a hard disk drive or an SD card.
In the present embodiment, the set value data of the external storage device 20 can be rewritten from a PC (personal computer) 25.

As the external storage device 20, in addition to a storage medium such as a hard disk drive or an SD card, an ID chip attached to a toner cartridge for recording a toner lot or the like can also be used.
As an advantage, even if the operator forgets the setting when changing the toner type, the toner type of the ID chip information is automatically recognized and set (rewritten) to an appropriate value.
That is, it is possible to reduce the work at the time of toner switching and reduce setting errors.

Items to be set for each toner type will be described.
[Toner adhesion amount]
Since the intended use of the toner type is different, the target adhesion amount is also different.
For example, as a use of clear toner, there is glossing. In this case, it is necessary to set the adhesion amount so as to achieve a target gloss.
Further, the application of the white toner needs to be set to an adhesion amount for reproducing white, but the same adhesion amount setting is not always used.

Table 1 shows the relationship between the toner type and each optimum adhesion amount setting, but the results are different from each other, and it can be said that it is necessary to change the adhesion amount for each toner. In Table 1, the unit is [mg / cm ² ].
Instead of the toner adhesion amount, the toner coverage may be a value that changes for each toner type.
Further, as a value to be changed for each toner type, an adhesion amount conversion coefficient for converting the output of the toner adhesion amount detection unit to the adhesion amount may be used.

[Aim of line width (dot diameter)]
As in the case of the toner adhesion amount, the aim of the line width is not the same depending on the toner used and its purpose.
For example, when white toner is used, it is conceivable to reduce the target line width (dot diameter) in order to improve the reproducibility of small characters.

[Toner replenishment amount]
Although the fluidity varies depending on the toner type, as the replenishment operation from the replenishment unit (toner supply unit 121) to the developing unit, the drive time per unit time is controlled, and when this drive time is not changed for each toner, Density decreases and fluctuations increase.
Table 2 evaluates the change in image density when the supply amount is changed by changing the drive time of the supply unit. The unit of the replenishment amount is [mg / sec].
The optimum replenishment amount differs for each toner type, and it can be said that it is necessary to change the replenishment amount for each toner type.

[Development potential upper limit]
The potential setting range to be used varies depending on the charging performance depending on the toner type.
This is because the upper limit of the development potential is defined from a region where the carrier is developed and an abnormal image on a white spot is generated on the image.
That is, the area where the carrier is developed, that is, the area where the abnormal image is generated varies depending on the toner charge amount and the resistance of the carrier type to be combined.
FIG. 5 is an evaluation of the development potential region where white spots occur depending on the toner type.

As a result, the optimum development potential upper limit differs for each toner type, and it can be said that the development potential upper limit needs to be changed for each toner type. The same applies to the lower limit value.
For the same reason, it is desirable to change the upper limit value of the background potential for each toner type.
FIG. 6 is an evaluation of the area of the background potential where white spots occur.
As a result, the optimum background potential differs for each toner type, and it can be said that the background potential needs to be changed for each toner type.
The same applies to the lower limit of the background potential.

[Charging section cleaning cycle]
When transfer residual toner or the like passes through the photosensitive member cleaning portion, charging failure due to contamination of the charging portion occurs, resulting in an abnormal image.
In the present embodiment, as described above, the charging roller is always cleaned with the charging cleaner roller. However, the charging roller and the wire may be cleaned by periodically moving the cleaning unit.
In such a configuration, it is necessary to change the cleaning cycle from the generation cycle because the additive species and amount used differ depending on the toner type.
FIG. 7 shows the rank of the streak image resulting from the charging roller contamination, and the number of generated images varies depending on the toner type. It can be said that it is necessary to change the charging portion cleaning cycle for each toner type.

[Transfer current setting]
When the charge amount is different for each toner type, an appropriate transfer current setting value is different as shown in FIGS. Therefore, the optimum image quality can be obtained by changing the transfer current setting for each toner.
FIG. 8 is for primary transfer from the photosensitive drum 122 to the intermediate transfer belt 143, and FIG. 9 is for secondary transfer from the intermediate transfer belt 143 to the paper.

[Lubricant application amount setting]
When the additive type and amount differ for each toner type, as shown in FIG. 10, there is a difference in the likelihood of an abnormal image due to the adhesion of the additive to the photoreceptor. In FIG. 10, the lubricant is indicated as a lubricant.
In order to suppress this, it is necessary to set the lubricant coating amount to an optimum value for each toner.

[Fixing temperature setting]
When the material, additive type, and amount differ for each toner type, as shown in FIG. 11, the appropriate fixing temperature setting value that satisfies the fixing property is different.
Therefore, fixing property can be secured by changing the fixing temperature for each toner.

[Line speed setting]
If fixability cannot be obtained even if the fixing temperature is lowered, the linearity (driving speed) is lowered to ensure the fixability.
As shown in FIG. 12, it is possible to ensure the fixability by changing the setting for each linear velocity when the material, additive type and amount differ for each toner type.

As described above, in the present invention, the address referred to by the device is not divided for each toner, but one address is used.
The setting value for each toner is stored in the external storage device, and the address setting value is changed at the same time as the toner switching, whereby the number of storage areas required by the apparatus main body can be reduced.
In addition, it is possible to suppress the frequency of occurrence of problems due to different addresses referenced by the device for each toner.
In addition to the above, the external storage means may be a storage unit in the network accessible via the network I / F 102.
Further, in the above-described embodiment, the example in which the image forming units for the process colors Y, M, C, and K are fixed and the other special color materials are changed has been described. However, in the multicolor image forming apparatus that replaces the process colors Can be similarly implemented.

DESCRIPTION OF SYMBOLS 20 External storage device as an external storage means 120 Image forming unit as an image forming unit 122 Photosensitive drum as an image carrier 125 Developing unit as a developing device 128 Protective agent coating device as means for applying a lubricant

JP 2012-58466 A JP 2012-83707 A

Claims (10)

It is possible to replace the image forming unit with a plurality of image forming units for each toner color that form an electrostatic latent image on an image carrier and visualize the electrostatic latent image as a toner image by a developing device. In an image forming apparatus,
Save the setting values that need to be changed for each toner type in the external storage means,
A device that configures an image forming apparatus and uses a different setting value for each type of toner has a fixed address to be referenced,
When the image forming unit is replaced and a change in toner type is recognized, an appropriate setting value for the replaced toner is extracted from the external storage unit and input to the address. Forming equipment. The image forming apparatus according to claim 1.
An image forming apparatus characterized in that recognition of change in toner type is based on toner ID chip information. The image forming apparatus according to claim 1, wherein
An image forming apparatus, wherein the set value to be changed for each type of toner is for the toner adhesion amount. The image forming apparatus according to claim 1, wherein
An image forming apparatus according to claim 1, wherein the developing device has means for replenishing toner, and the setting value changed for each type of toner is for the amount of toner replenishment. The image forming apparatus according to claim 1, wherein
An image forming apparatus, wherein the setting value to be changed for each type of toner is for a development potential. The image forming apparatus according to claim 1, wherein
An image forming apparatus, wherein the setting value to be changed for each toner type is for the background potential. The image forming apparatus according to claim 1, wherein
The image forming apparatus according to claim 1, wherein the set value to be changed for each type of toner is for a transfer current when the toner image is transferred. The image forming apparatus according to claim 1, wherein
An image forming apparatus comprising: means for applying a lubricant to the image carrier; and a set value changed for each type of toner is for a lubricant application amount. The image forming apparatus according to claim 1, wherein
The image forming apparatus according to claim 1, wherein the set value to be changed for each type of toner is a fixing temperature at which the toner image is fixed on a recording medium. The image forming apparatus according to claim 1, wherein
An image forming apparatus, wherein the setting value changed for each type of toner is for the driving speed of the apparatus.

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