JP2021063914A - Image forming apparatus - Google Patents

Abstract

To provide an image forming apparatus that can maintain the image quality of an image to be formed without replacing a photoreceptor unit.SOLUTION: An image forming apparatus 1 comprises: a photoreceptor drum 413 on which a toner image is formed by an electrophotographic system; a lubricant application unit 82 that applies lubricant on a surface of the photoreceptor drum 413; a control unit 100 that controls the image forming apparatus 1; and a spring pressure detection unit 110 that detects a pressing force P of a spring used for the lubricant application unit 82. The control unit 100 executes predetermined processing according to the pressing force P of the spring detected by the spring pressure detection unit 110. When the pressing force P of the spring detected by the spring pressure detection unit 110 becomes equal to or less than a predetermined pressure (threshold), the control unit 100 executes a notification for prompting a user to replace the spring as the predetermined processing.SELECTED DRAWING: Figure 1

Description

This disclosure relates to an image forming apparatus that forms an image on a sheet.

An image forming apparatus that forms an image on a sheet may employ a lubricant coating portion that supplies a lubricant to a photoconductor unit in order to prevent image defects. When the lubricant-coated portion is adopted, it is necessary for the lubricant-coated portion to continue to supply a certain amount of lubricant to the photoconductor unit in order to maintain the image quality of the image formed by the image forming apparatus.

However, the lubricant-applied portion presses the solid lubricant against the lubricant-coated brush with a constant pressing force and rotates the lubricant-coated brush at a constant speed. Therefore, when the lubricant-coated brush deteriorates, a certain amount of lubricant is applied to the photoconductor unit. There is a problem that the image quality of the image formed by the image forming apparatus deteriorates.

Therefore, Patent Document 1 discloses an image forming apparatus that detects the scraping force when the lubricant-applied brush scrapes the solid lubricant and determines the replacement time of the lubricant-coated brush based on the detection result. In Patent Document 1, by displaying the replacement time of the lubricant coating brush on the image forming apparatus, the user is urged to replace the lubricant coating brush, and the lubricant supplied to the photoconductor unit is kept at a constant amount.

Japanese Unexamined Patent Publication No. 2013-130798

However, in the technique disclosed in Patent Document 1, if the lubricant supplied to the photoconductor unit cannot be kept at a constant amount even if the lubricant coating brush is replaced, the photoconductor unit itself needs to be replaced and is formed. High costs were required to maintain image quality.

The present disclosure has been made to solve the above-mentioned problems, and an object in a certain aspect is an image forming apparatus capable of maintaining the image quality of an image to be formed without exchanging a photoconductor unit. Is to provide.

According to a certain embodiment, an image forming apparatus for forming an image on a sheet, an image carrier on which a toner image is formed by an electrophotographic method, a lubricant coating portion for applying a lubricant on the surface of the image carrier, and an image. A control unit that controls the forming device and a spring pressure detection unit that detects the pressing force of the spring used for the lubricant coating unit are provided, and the control unit is predetermined according to the pressing force of the spring detected by the spring pressure detecting unit. Execute the process.

Preferably, the lubricant coating portion includes a lubricant coating brush arranged in sliding contact with the image carrier, a driving unit for driving the lubricant coating brush, and a lubricant disposed in sliding contact with the lubricant coating brush. The drive unit applies the lubricant to the surface of the image carrier by driving the lubricant application brush.

Preferably, the spring presses the lubricant against the lubricant-applied brush.
Preferably, the spring presses the lubricant-coated brush against the image carrier.

Preferably, the spring pressure detecting unit calculates the torque of the driving unit that drives the lubricant coating brush, and detects the pressing force of the spring based on the calculated torque.

Preferably, the spring pressure detecting unit calculates the sliding distance of the lubricant coating brush and detects the pressing force of the spring based on the calculated sliding distance.

Preferably, the spring pressure detecting unit calculates the sliding time of the lubricant coating brush and detects the pressing force of the spring based on the calculated sliding time.

Preferably, the spring pressure detecting unit calculates the number of sheets on which the image is formed by the image carrier, and detects the pressing force of the spring based on the calculated number of sheets.

Preferably, the spring pressure detecting unit is a pressure sensor that detects the pressing force of the spring.
Preferably, the spring pressure detecting unit calculates the amount of lubricant applied to the image carrier and detects the pressing force of the spring based on the calculated amount of lubricant.

Preferably, when the pressing force of the spring detected by the spring pressure detecting unit becomes equal to or less than the threshold value, the control unit notifies the spring to be replaced as a predetermined process.

Preferably, the control unit controls the drive of the image carrier and the drive of the lubricant coating unit, and when the pressing force of the spring detected by the spring pressure detection unit becomes equal to or less than the threshold value, the image carrier is driven as a predetermined process. And change the drive of at least one of the drives of the lubricant coating part.

Preferably, an environmental sensor capable of detecting at least one of the temperature and humidity of the environment in which the image forming apparatus is installed is further provided, and the spring pressure detecting unit presses the spring according to the result detected by the environmental sensor. Correct the pressure.

Preferably, an environment sensor capable of detecting at least one of the temperature and humidity of the environment in which the image forming apparatus is installed is further provided, and the threshold value is changed according to the result detected by the environment sensor.

Preferably, the spring pressure detecting unit clears a counter for counting a value required for calculation each time the pressing force of the spring is detected.

Preferably, the control unit prohibits image formation on the seat when the pressing force of the spring detected by the spring pressure detecting unit is equal to or less than a predetermined value.

An image forming apparatus according to an embodiment can maintain the image quality of the image to be formed without exchanging the photoconductor unit.

It is a figure which shows schematic the whole structure of the image forming apparatus in Embodiment 1. FIG. It is a block diagram which shows the outline of the structure of the image forming apparatus in Embodiment 1. FIG. It is a figure which shows the main part structure of the drum cleaning apparatus of the image forming apparatus in Embodiment 1. FIG. It is a flowchart for demonstrating the process in the lubricant coating part of the image forming apparatus in Embodiment 1. FIG. It is a block diagram which shows the outline of the structure of the image forming apparatus in Embodiment 2. FIG. It is a figure which shows the main part structure of the drum cleaning apparatus of the image forming apparatus in Embodiment 2. FIG.

<Embodiment 1>
The first embodiment will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are designated by the same reference numerals and the description thereof will not be repeated.

FIG. 1 is a diagram schematically showing the overall configuration of the image forming apparatus 1 according to the first embodiment. FIG. 2 is a block diagram showing an outline of the configuration of the image forming apparatus according to the first embodiment. The image forming apparatus 1 will be described with reference to FIGS. 1 and 2. The image forming apparatus 1 is an intermediate transfer type color image forming apparatus using electrophotographic process technology.

The image forming apparatus 1 transfers (primary transfer) each color toner image of C (cyan), M (magenta), Y (yellow), and K (black) formed on the photoconductor drum 413 to the intermediate transfer belt 421. An image is formed by superimposing toner images of four colors on the intermediate transfer belt 421 and then transferring (secondary transfer) to paper (sheet). Further, in the image forming apparatus 1, the photoconductor drums 413 corresponding to the four colors of CMYK are arranged in series in the traveling direction of the intermediate transfer belt 421, and the toner images of each color are sequentially transferred to the intermediate transfer belt 421 in one procedure. The tandem method is adopted.

As shown in FIGS. 1 and 2, the image forming apparatus 1 includes an image reading unit 10, an operation display unit 20, an image processing unit 30, an image forming unit 40, a paper conveying unit 50, a fixing unit 60, and a control unit 100. .. The control unit 100 includes a CPU (Central Processing Unit) 101, a ROM (Read Only Memory) 102, a RAM (Random Access Memory) 103, and the like. The CPU 101 reads a program according to the processing content from the ROM 102, develops it in the RAM 103, and centrally controls the operation of each block of the image forming apparatus 1 in cooperation with the expanded program. At this time, various data stored in the storage unit 72 are referred to. The storage unit 72 is composed of, for example, a non-volatile semiconductor memory (so-called flash memory) or a hard disk drive.

The control unit 100 transmits and receives various data to and from an external device (for example, a personal computer) connected to a communication network such as a LAN (Local Area Network) or WAN (Wide Area Network) via the communication unit 71. Do. The control unit 100 receives, for example, image data transmitted from an external device, and causes the paper to form an image based on the image data (input image data). The communication unit 71 is composed of a communication control card such as a LAN card.

The temperature / humidity sensor 73 is an environment sensor capable of detecting at least one of the temperature and humidity of the environment in which the image forming apparatus 1 is installed.

The image reading unit 10 includes an automatic document feeding device 11 called an ADF (Auto Document Feeder), a document image scanning device 12 (scanner), and the like. The automatic document feeding device 11 conveys the document D placed on the document tray by the conveying mechanism and sends it out to the document image scanning device 12. The automatic document feeding device 11 can continuously read a large number of images (including both sides) of the documents D placed on the document tray at once.

The document image scanning device 12 optically scans the document conveyed on the contact glass from the automatic document feeding device 11 or the document placed on the contact glass, and the reflected light from the document is a CCD (Charge Coupled Device). ) An image is formed on the light receiving surface of the sensor 12a, and the original image is read. The image scanning unit 10 generates input image data based on the scanning result by the document image scanning device 12. The image processing unit 30 performs predetermined image processing on the input image data.

The operation display unit 20 is composed of, for example, a liquid crystal display (LCD) with a touch panel, and functions as a display unit 21 and an operation unit 22. The display unit 21 displays various operation screens, an image status display, an operation status of each function, and the like according to a display control signal input from the control unit 100. The operation unit 22 includes various operation keys such as a numeric keypad and a start key, receives various input operations by the user, and outputs an operation signal to the control unit 100. In the present embodiment, the display unit 21 displays information related to the replacement of the spring of the lubricant pressing portion 823 or the unit including the spring of the lubricant pressing portion 823, and the print prohibition state due to the deterioration of the spring of the lubricant pressing portion 823.

The image processing unit 30 includes a circuit or the like that performs digital image processing according to initial settings or user settings on the input image data. For example, the image processing unit 30 performs gradation correction based on the gradation correction data (gradation correction table) under the control of the control unit 100. Further, the image processing unit 30 performs various correction processes such as color correction and shading correction, compression processing, and the like, in addition to gradation correction, on the input image data. The image forming unit 40 is controlled based on the image data subjected to these processes.

The image forming unit 40 is an image forming unit 41Y, 41M, 41C, 41K, and an intermediate transfer unit for forming an image with each colored toner of Y component, M component, C component, and K component based on the input image data. It is equipped with 42 and the like.

The image forming units 41Y, 41M, 41C, 41K for the Y component, the M component, the C component, and the K component have the same configuration. For convenience of illustration and description, common components are indicated by the same reference numerals, and when distinguishing them, they are indicated by adding Y, M, C, or K to the reference numerals. In FIG. 1, the reference numerals are given only to the components of the image forming unit 41Y for the Y component, and the reference numerals are omitted for the other components of the image forming units 41M, 41C, and 41K.

The image forming unit 41 includes an exposure device 411, a developing device 412, a photoconductor drum 413, a charging device 414, a drum cleaning device 415, and the like.

The photoconductor drum 413 has, for example, an undercoat layer (UCL: Under Coat Layer) and a charge generation layer (CGL: Charge Generation Layer) on the peripheral surface of a conductive cylinder (aluminum element tube) made of aluminum having a drum diameter of 80 mm. , A negatively charged organic photo-conductor (OPC) in which a charge transport layer (CTL) is sequentially laminated. The charge generation layer is made of an organic semiconductor in which a charge generation material (for example, a phthalocyanine pigment) is dispersed in a resin binder (for example, polycarbonate), and a pair of positive charges and negative charges are generated by exposure by an exposure apparatus 411. The charge transport layer is composed of a hole transport material (electron donating nitrogen-containing compound) dispersed in a resin binder (for example, polycarbonate resin), and transports positive charges generated in the charge generation layer to the surface of the charge transport layer. To do.

The photoconductor drum 413 rotates at a constant peripheral speed by controlling the drive current supplied to the drive motor (not shown) that rotates the photoconductor drum 413 by the control unit 100. Here, it is assumed that a photoconductor drum 413 having a drum diameter of 80 mm and a film thickness of a photoconductor layer composed of an undercoat layer, a charge generation layer, and a charge transport layer of 25 to 32 μm is used.

The charging device 414 uniformly charges the surface of the photoconductor drum 413 having photoconductivity to a negative electrode property. The exposure apparatus 411 is composed of, for example, a semiconductor laser, and irradiates the photoconductor drum 413 with a laser beam corresponding to an image of each color component. Positive charges are generated in the charge generation layer of the photoconductor drum 413 and transported to the surface of the charge transport layer, so that the surface charge (negative charge) of the photoconductor drum 413 is neutralized. An electrostatic latent image of each color component is formed on the surface of the photoconductor drum 413 due to a potential difference from the surroundings. The developing device 412 contains a developer for each color component (for example, a two-component developer composed of a toner having a small particle size and a magnetic material), and adheres the toner for each color component to the surface of the photoconductor drum 413. Visualizes the electrostatic latent image and forms a toner image.

The drum cleaning device 415 includes a cleaning unit and a lubricant coating unit 82. The cleaning unit removes the transfer residual toner remaining on the surface of the photoconductor drum 413 after the primary transfer. The lubricant application unit 82 applies a lubricant to the surface of the photoconductor drum 413. Details of the drum cleaning device 415 will be described later.

The intermediate transfer unit 42 includes an intermediate transfer belt 421 as an intermediate transfer body, a primary transfer roller 422, a secondary transfer roller 423, a drive roller 424, a driven roller 425, a belt cleaning device 426, and the like.

The intermediate transfer belt 421 is composed of an endless belt and is stretched on a drive roller 424 and a driven roller 425. The intermediate transfer belt 421 travels at a constant speed in the direction of arrow A due to the rotation of the drive roller 424. When the intermediate transfer belt 421 is pressed against the photoconductor drum 413 by the primary transfer roller 422, the toner images of each color are sequentially superimposed on the intermediate transfer belt 421 and the primary transfer is performed. Then, when the paper S passes through the transfer nip formed by the secondary transfer roller 423 being pressed against the intermediate transfer belt 421, the toner image primary transferred to the intermediate transfer belt 421 is secondarily transferred to the paper S. Toner.

The belt cleaning device 426 has a belt cleaning blade or the like that is slidably contacted with the surface of the intermediate transfer belt 421, and removes the transfer residual toner remaining on the surface of the intermediate transfer belt 421 after the secondary transfer.

The fixing unit 60 fixes the toner image on the paper S by heating and pressurizing the conveyed paper S with the fixing nip. The fixing unit 60 may be provided with an air separation unit that separates the paper S from the fixing surface side member (for example, the fixing belt) or the back surface side support member (for example, the pressure roller) by blowing air.

The paper transport unit 50 includes a paper feed unit 51, a paper discharge unit 52, a transport roller unit 53, and the like. The three paper feed tray units 51a to 51c constituting the paper feed unit 51 accommodate the paper S (standard paper, special paper) identified based on the basis weight, size, etc. for each preset type. ..

The transport roller unit 53 has a plurality of transport roller pairs such as a resist roller pair 53a. The paper S housed in the paper feed tray units 51a to 51c is sent out one by one from the uppermost portion, and is conveyed to the image forming unit 40 by the transfer roller unit 53. At this time, the resist roller portion in which the resist roller pair 53a is arranged corrects the inclination of the fed paper S and adjusts the transfer timing. Then, in the image forming unit 40, the toner image of the intermediate transfer belt 421 is collectively secondarily transferred to one surface of the paper S, and the fixing step is performed in the fixing unit 60. The image-formed paper S is discharged to the outside of the machine by the paper ejection unit 52 provided with the paper ejection roller 52a.

As described above, the image forming apparatus 1 includes a photoconductor drum 413 having photoconductivity, a charging device 414 that uniformly charges the surface of the photoconductor drum 413, and static electricity on the surface of the photoconductor drum 413 by irradiation with light. An exposure device 411 that forms a latent image, a developing device 412 that visualizes an electrostatic latent image by adhering toner to the surface of the photoconductor drum 413 to form a toner image, and a surface of the photoconductor drum 413 after primary transfer. It is provided with a drum cleaning device 415 for removing the transfer residual toner remaining in the.

FIG. 3 is a diagram showing a main configuration of the drum cleaning device 415 according to the first embodiment. As shown in FIG. 3, the drum cleaning device 415 includes a cleaning unit 81 and a lubricant coating unit 82.

Each component of the cleaning unit 81 and the lubricant coating unit 82 is attached to the storage case C, which is the frame of the drum cleaning device 415, by an appropriate method. The cleaning unit 81 includes a drum cleaning blade 811 and a toner recovery screw 812.

The drum cleaning blade 811 is an elastic member obtained by molding urethane rubber or the like into a flat plate shape, and has a width substantially equal to the width in the axial direction (main scanning direction) of the photoconductor drum 413. The drum cleaning blade 811 has a predetermined free length (for example, 9 mm), and has a predetermined contact with the photoconductor drum 413 from the counter direction (the direction in which the edge portion is stretched when the photoconductor drum 413 rotates). They are arranged so as to be in sliding contact with an angle (for example, 15 °) and a normal load (for example, 20N).

At the time of image formation, as the photoconductor drum 413 rotates, the transfer residual toner remaining on the surface of the photoconductor drum 413 is scraped off by the drum cleaning blade 811. The scraped transfer residual toner is sent to a waste toner recovery container (not shown) by the toner recovery screw 812.

The lubricant coating unit 82 includes a lubricant coating brush 821, a solid lubricant 822, a lubricant pressing unit 823, a leveling blade 824, a spring pressure detecting unit 825, and the like.

The lubricant coating brush 821 is a roller-shaped brush in which a base cloth in which fibers such as polyester are planted is wound around a core metal, and has a width substantially equal to the axial width of the photoconductor drum 413. Here, it is assumed that a lubricant coating brush 821 having an outer diameter of 14 mm is used. The lubricant application brush 821 is fixed so that the surface of the photoconductor drum 413 bites into the tip of the brush by a predetermined amount (for example, the bite amount: 0.5 to 1.5 mm), which is opposite to the rotation of the photoconductor drum 413. Rotate in the direction.

The rotation speed of the lubricant coating brush 821 is adjusted by the control unit 100 controlling the drive current supplied to the drive motor M that rotates the lubricant coating brush 821. Further, the drive current is input to the control unit 100 and used for calculating the drive torque and the like.

The solid lubricant 822 is a solidified lubricant (for example, pencil hardness: equivalent to F to HB) and is fixed to a holder (not shown) of the lubricant pressing portion 823. As the lubricant, for example, zinc stearate (ZnSt) is applied.

The lubricant pressing portion 823 has a biasing member such as a spring, and presses the solid lubricant 822 fixed to one end side of the biasing member with a predetermined pressing force P toward the lubricant coating brush 821. The pressing force P by the lubricant pressing portion 823 is changed according to the brush state of the lubricant applying brush 821 (for example, 1.5 to 4.0 N). The leveling blade 824 has the same configuration as the drum cleaning blade 811.

The leveling blade 824 has a predetermined contact angle (for example, 50 °) and penetration amount with respect to the photoconductor drum 413 from the trailing direction (the direction in which the edge portion is dragged when the photoconductor drum 413 rotates). It is arranged so that it slides in contact with.

The control unit 100 has a spring pressure detecting unit 110 that detects a pressing force P in which the spring of the lubricant pressing unit 823 presses the solid lubricant 822 against the lubricant application brush 821. The spring pressure detecting unit 110 detects the pressing pressure P of the spring based on the information (spring calculation information) from the lubricant applying unit 82 or the image forming unit 40. The spring pressure detection unit 110 is realized by a CPU 101 provided in the control unit 100 and software executed by the CPU 101. The details of the spring pressure detection unit 110 will be described later.

At the time of image formation, the lubricant application brush 821 rotates to scrape the lubricant from the surface of the solid lubricant 822, and the scraped lubricant is applied to the surface of the photoconductor drum 413 at the contact portion with the photoconductor drum 413. To. Then, the applied lubricant is leveled by the leveling blade 824 so as to have a uniform thickness.

In the present embodiment, not only the deterioration of the lubricant application brush 821 but also the deterioration of the spring which is the urging member of the lubricant pressing portion 823 has an influence on the cause that the lubricant supplied to the photoconductor drum 413 cannot be kept at a constant amount. The control unit 100 executes a predetermined process according to the pressing force of the spring detected by the spring pressure detecting unit 110 based on the fact that the control unit 100 has been found to be doing so.

Further, even if the lubricant application brush 821 is replaced, a certain amount of lubricant cannot be applied to the photoconductor drum 413, and when image formation is performed, noise is generated in the formed image. The photoconductor unit including at least the body drum 413 and the drum cleaning device 415 was replaced. However, since the life of the photoconductor drum 413 is longer than the life of the spring that is the urging member of the lubricant pressing portion 823, even if the photoconductor unit is replaced, a certain amount of lubricant is used before the life of the photoconductor drum 413 is reached. Can no longer be applied to the photoconductor drum 413, and even if the photoconductor unit is replaced, noise is generated in the formed image from the life of the spring to the life of the photoconductor drum 413.

Therefore, in the present embodiment, for example, the pressing force of the spring detected by the spring pressure detecting unit 110 prompts the user to replace the spring that has reached the end of its life, so that the image formed without replacing the photoconductor unit. It is possible to prevent the generation of noise.

A specific process in the lubricant coating unit 82 of the image forming apparatus 1 will be described in detail with reference to a flowchart. FIG. 4 is a flowchart for explaining the process in the lubricant coating unit 82 of the image forming apparatus 1 in the first embodiment.

First, the control unit 100 determines whether or not the print instruction given by the user is a print instruction for one page (step S1). Here, the print instruction given by the user is realized by, for example, the CPU 101 executing a predetermined program stored in the ROM 102 as the user performs a key operation for instructing image formation in the operation unit 22. To. The print instruction includes information such as the processing speed for executing the print and the color mode.

If it is not a print instruction for one page (NO in step S1), the control unit 100 ends the process. When the print instruction is for one page (YES in step S1), the control unit 100 acquires the sliding distance of the lubricant coating brush 821 (step S2). Here, the sliding distance of the lubricant coating brush 821 can be calculated from the processing speed information obtained by the print instruction, the drive time of the drive motor M for driving the lubricant coating brush 821, and the like.

Next, the control unit 100 acquires the drive torque of the drive motor M that drives the lubricant application brush 821 (step S3). Here, the drive torque of the lubricant coating brush 821 acquires the drive torque obtained by the drive torque detection mechanism of the drive motor M. For example, the drive torque detection mechanism monitors the drive current of the drive motor M and calculates the drive torque by detecting a change in the monitored current value.

In the control unit 100, the sliding distance of the lubricant coating brush 821 acquired in step S2 is equal to or more than a predetermined distance (for example, 250 km or more), or the drive torque acquired in step S3 is less than a predetermined value (for example, the drive current is less than 600 mA). ) Is determined (step S4).

When it is determined that the sliding distance of the lubricant application brush 821 acquired in step S2 is less than a predetermined distance and the drive torque acquired in step S3 is equal to or more than a predetermined value (NO in step S4), the control unit 100 presses the lubricant. The spring calculation information for calculating the pressing force P of the spring of the part 823 is acquired (step S5). Further, the control unit 100 calculates the pressing force P of the spring of the lubricant pressing unit 823 based on the acquired spring calculation information (step S6). The spring pressing force P calculated by the control unit 100 may be calculated as numerical data or as binary data of "normal" or "deteriorated".

Specifically, the pressing force P of the spring calculated by the control unit 100 will be described in detail below. In the first embodiment, the pressing force P of the spring is not provided, and the pressing force P of the spring is based on the information (spring calculation information) from the lubricant coating unit 82 or the image forming unit 40, without providing the pressure sensor that directly detects the pressing pressure P of the spring. Is detected. For example, the control unit 100 calculates the pressing force P of the spring from the sliding distance of the lubricant coating brush 821. Specifically, when the sliding distance of the lubricant coating brush 821 is less than 120 km, the control unit 100 detects that the pressing force P of the spring is "normal", and when the sliding distance of the lubricant coated brush 821 is 120 km or more, The pressing force P of the spring is detected as "deterioration".

Further, the control unit 100 may calculate the pressing force P of the spring from the sliding time of the lubricant coating brush 821. Here, the sliding time of the lubricant coating brush 821 can be obtained by dividing the sliding distance of the lubricant coating brush 821 by the speed of the drive motor M. Specifically, when the sliding time of the lubricant coating brush 821 is less than 100 hours, the control unit 100 detects that the pressing force P of the spring is "normal", and when the sliding time of the lubricant coating brush 821 is 100 km or more. , The pressing force P of the spring is detected as "deterioration".

Further, the control unit 100 may calculate the pressing force P of the spring from the driving torque of the driving motor M that drives the lubricant coating brush 821. Specifically, the control unit 100 detects that the pressing force P of the spring is "normal" when the driving torque of the lubricant coating brush 821 is 800 mA or more, and when the drive torque of the lubricant coating brush 821 is less than 800 mA, the spring The pressing force P is detected as "deterioration".

Further, the control unit 100 may calculate the pressing force P of the spring from the amount of the lubricant applied. In order to determine the amount of lubricant applied, for example, a detection sensor for detecting the lubricant of the powder scattered from the hairy member of the lubricant application brush 821 is provided, and the amount of the lubricant of the powder scattered from the lubricant application brush 821 is scratched by the lubricant. Since it has a linear relationship with the amount taken and consumed, the detection sensor accurately detects the amount of lubricant applied. As a method for determining the amount of lubricant applied, for example, the method disclosed in Japanese Patent Application Laid-Open No. 2013-101273 can be used. Specifically, when the lubricant application amount is less than 3.4 mg, the control unit 100 detects that the spring pressing force P is "normal", and when the lubricant application amount is 3.4 mg or more, the spring pressing force P is Detect as "deteriorated".

As described above, there are various methods for calculating the pressing force P of the spring, but even if one of these methods is selected to calculate the pressing force P of the spring, a plurality of methods can be combined to calculate the pressing force P of the spring. The pressing force P of may be calculated. Further, the calculation of the pressing force P of the spring may be corrected in consideration of the environment in which the image forming apparatus 1 is installed. For example, if the environment in which the image forming apparatus 1 is installed is a high temperature environment (environment of 35 degrees or higher) or a high humidity environment (environment of 80% or higher) (detection result of the temperature / humidity sensor 73), the lubricant application brush 821 The pressing force P of the spring may be calculated by multiplying the value such as the sliding distance of the spring by 1.1.

Further, the values of various counters (sliding distance of the lubricant coating brush 821, sliding time of the lubricant coating brush 821, number counter, etc.) required for calculating the pressing force P of the spring are cleared at a predetermined timing. .. For example, when the user operates a key to instruct image formation in the operation unit 22, the CPU 101 executes a predetermined program stored in the ROM 102 to clear the values of various counters.

The control unit 100 determines whether or not the pressing pressure P of the spring calculated in step S6 is equal to or lower than the predetermined pressure (step S7). When the spring pressing force P is calculated as binary data of "normal" or "deteriorated", the control unit 100 determines whether or not the spring pressing force P calculated in step S6 has become "deteriorated". To do. When the pressing pressure P of the spring is larger than the predetermined pressure (“normal”) (NO in step S7), the control unit 100 ends the process.

When the pressing pressure P of the spring is equal to or less than a predetermined pressure (“deterioration”) (YES in step S7), the control unit 100 prohibits the printing operation (step S8). Further, the control unit 100 displays on the display unit 21 a display prompting the user to replace the spring of the lubricant pressing unit 823.

Returning to step S4, when it is determined that the sliding distance of the lubricant application brush 821 acquired in step S2 is equal to or greater than a predetermined distance, or the drive torque acquired in step S3 is less than a predetermined value (YES in step S4), control is performed. The unit 100 displays on the display unit 21 a display prompting the user to replace the lubricant application unit 82. The lubricant coating portion 82 is a unit component including at least a lubricant coating brush 821, a solid lubricant 822, and a spring of the lubricant pressing portion 823.

As described above, the image forming apparatus 1 according to the first embodiment includes a photoconductor drum 413 on which a toner image is formed by an electrophotographic method, and a lubricant coating unit 82 for applying a lubricant to the surface of the photoconductor drum 413. The control unit 100 for controlling the image forming apparatus 1 and the spring pressure detecting unit 110 for detecting the pressing force P of the spring used for the lubricant coating unit 82 are provided. The control unit 100 executes a predetermined process according to the pressing force P of the spring detected by the spring pressure detecting unit 110. When the pressing force P of the spring detected by the spring pressure detecting unit 110 becomes equal to or less than a predetermined pressure (threshold value), the control unit 100 notifies the user to replace the spring as a predetermined process. As a result, the image forming apparatus 1 according to the first embodiment can detect the deterioration of the spring of the lubricant pressing portion 823, which is one of the factors that reduce the amount of the lubricant supplied to the photoconductor drum 413, and forms the image forming apparatus 1. It is possible to urge the user to replace the spring before the image to be imaged causes poor image quality, and the image quality of the formed image can be maintained without exchanging the photoconductor unit.

The control unit 100 controls the drive of the photoconductor drum 413 and the drive of the lubricant application unit 82, and the spring pressure detection unit 110 controls the drive of the photoconductor drum 413 and the lubricant application unit 82. When the detected pressing force P of the spring becomes a predetermined pressure (threshold value) or less, at least one of the drive of the photoconductor drum 413 and the drive of the lubricant coating unit 82 may be changed as a predetermined process. For example, when the control unit 100 determines that the spring of the lubricant pressing unit 823 has deteriorated, the drive of the photoconductor drum 413 or the drive of the lubricant application brush 821 is delayed, and the lubricant is supplied to the photoconductor drum 413. The drive may be controlled as follows. Further, when the spring of the lubricant pressing unit 823 deteriorates, the control unit 100 may notify the user to replace the spring.

The lubricant application portion 82 is arranged in a state of being in sliding contact with the lubricant application brush 821, a drive motor M for driving the lubricant application brush 821, and the lubricant application brush 821. It has a solid lubricant 822 and. The drive motor M applies the lubricant to the surface of the photoconductor drum 413 by driving the lubricant application brush 821.

As shown in FIG. 3, the spring of the lubricant pressing portion 823 presses the solid lubricant 822 against the lubricant coating brush 821 and presses the lubricant coating brush 821 against the photoconductor drum 413. That is, the springs of the photoconductor drum 413, the lubricant application brush 821, the solid lubricant 822, and the lubricant pressing portion 823 are arranged in a straight line. The spring that presses the solid lubricant 822 against the lubricant application brush 821 and the spring that presses the lubricant application brush 821 against the photoconductor drum 413 are not common springs, but may be separate springs. That is, the spring may press the lubricant coating brush 821 against the photoconductor drum 413.

The spring pressure detecting unit 110 may calculate the torque of the drive motor M for driving the lubricant coating brush 821, and detect the pressing force P of the spring based on the calculated torque. The spring pressure detecting unit 110 may calculate the sliding distance of the lubricant coating brush 821 and detect the pressing force P of the spring based on the calculated sliding distance. As a result, it is not necessary to newly install a pressure sensor or the like.

The spring pressure detecting unit 110 may calculate the sliding time of the lubricant coating brush 821 and detect the pressing force P of the spring based on the calculated sliding time. The spring pressure detecting unit 110 may calculate the number of sheets on which the image is formed by the photoconductor drum 413, and detect the pressing force P of the spring based on the calculated number of sheets. The spring pressure detection unit 110 may calculate the amount of lubricant applied to the lubricant application brush 821 and detect the pressing force P of the spring based on the calculated amount of lubricant. As a result, it is not necessary to newly install a pressure sensor or the like.

The image forming apparatus 1 may further include a temperature / humidity sensor 73 capable of detecting at least one of the temperature and humidity of the environment in which the image forming apparatus 1 is installed. The spring pressure detecting unit 110 may correct the pressing force P of the spring according to the result detected by the temperature / humidity sensor 73. Further, instead of correcting the pressing force P of the spring, the control unit 100 may change the predetermined pressure (threshold value) according to the result detected by the temperature / humidity sensor 73.

Further, the spring pressure detecting unit 110 may clear the counter for counting the value required for the calculation every time the pressing pressure P of the spring is detected. When the pressing force P of the spring detected by the spring pressure detecting unit 110 becomes equal to or less than a predetermined value (predetermined pressure), the control unit 100 may prohibit the formation of an image on the sheet.
<Embodiment 2>
In the image forming apparatus 1 according to the first embodiment, the pressing force P of the spring of the lubricant pressing unit 823 is calculated by the spring pressure detecting unit 110 based on the information (spring calculation information) from the lubricant applying unit 82 or the image forming unit 40. ing. However, in the image forming apparatus according to the second embodiment, a pressure sensor for detecting the pressing force P of the spring of the lubricant pressing portion is provided. Therefore, in the second embodiment, it is not necessary to indirectly calculate the pressing force P of the spring from the information (spring calculation information) from the lubricant coating unit 82 or the image forming unit 40, and the pressure sensor can directly detect it.

FIG. 5 is a block diagram showing an outline of the configuration of the image forming apparatus according to the second embodiment. FIG. 5 has the same configuration as that shown in FIG. 2 except that the lubricant pressing unit 823 is provided with the spring pressure detecting unit 825, which is a pressure sensor, and the control unit 100 is not provided with the spring pressure detecting unit 110. Therefore, among the configurations shown in FIG. 5, the same configurations as those shown in FIG. 2 are designated by the same reference numerals, and detailed description thereof will not be repeated. FIG. 6 is a diagram showing a main configuration of the drum cleaning device 415 of the image forming apparatus according to the second embodiment. FIG. 6 has the same configuration as that shown in FIG. 3 except that the lubricant pressing portion 823 is provided with a spring pressure detecting portion 825 which is a pressure sensor. Therefore, among the configurations shown in FIG. 6, the same configurations as those shown in FIG. 3 are designated by the same reference numerals, and detailed description thereof will not be repeated.

As shown in FIGS. 5 and 6, the drum cleaning device 415 has a spring pressure detecting unit 825 that directly detects the pressing force P of the spring, and the control unit 100 determines the result detected by the spring pressure detecting unit 825. Depending on the situation, the pressing force P of the spring may be determined to be "normal" or "deteriorated". Specifically, when the detection result of the spring pressure detection unit 825 is 2.0 N or more, the control unit 100 determines that the spring pressing pressure P is "normal", and the detection result of the spring pressure detection unit 825 is 2.0 N. If it is less than, the pressing force P of the spring is judged to be "deteriorated".

As described above, the spring pressure detecting unit 825 is a pressure sensor that detects the pressing force P of the spring. Therefore, the spring pressure detecting unit 825 can directly detect the pressing force P of the spring. The spring pressure detection unit 825 described in the second embodiment can be appropriately combined with the configuration described in the first embodiment.

It should be considered that the embodiments disclosed this time are exemplary in all respects and not restrictive. The scope of the present invention is shown by the scope of claims rather than the above description, and it is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1 image forming device, 10 image reading unit, 11 automatic document feeding device, 12 document image scanning device, 12a CCD sensor, 20 operation display unit, 21 display unit, 22 operation unit, 30 image processing unit, 40 image forming unit, 41 Image forming unit, 42 Intermediate transfer unit, 50 Paper transfer unit, 51 Paper feed unit, 51a, 51c Paper feed tray unit, 52 Paper discharge unit, 52a Paper discharge roller, 53 Transfer roller unit, 53a Resist roller pair, 60 Fixation Unit, 71 Communication unit, 72 Storage unit, 73 Temperature / humidity sensor, 81 Cleaning unit, 82 Lubricant coating unit, 100 Control unit, 102 ROM, 103 RAM, 110,825 Spring pressure detector, 411 Exposure device, 412 Developer, 413 Photoreceptor drum, 414 Charging device, 415 Drum cleaning device, 421 Intermediate transfer belt, 422 Primary transfer roller, 423 Secondary transfer roller, 424 Drive roller, 425 Driven roller, 426 Belt cleaning device, 811 Drum cleaning blade, 812 Toner Recovery screw, 821 lubricant coating brush, 822 solid lubricant, 823 lubricant press, 824 blade.

Claims (16)

An image forming device that forms an image on a sheet.
An image carrier on which a toner image is formed by electrophotographic method,
A lubricant coating portion for applying a lubricant to the surface of the image carrier, and a lubricant coating portion.
A control unit that controls the image forming apparatus and
A spring pressure detecting unit for detecting the pressing force of the spring used for the lubricant coating unit is provided.
The control unit is an image forming apparatus that executes a predetermined process according to a pressing force of the spring detected by the spring pressure detecting unit. The lubricant-coated part is
A lubricant-applied brush that is placed in sliding contact with the image carrier,
The drive unit that drives the lubricant application brush and
It has a lubricant that is placed in sliding contact with the lubricant application brush.
The image forming apparatus according to claim 1, wherein the driving unit applies a lubricant to the surface of the image carrier by driving the lubricant applying brush. The image forming apparatus according to claim 2, wherein the spring presses the lubricant against the lubricant application brush. The image forming apparatus according to claim 2 or 3, wherein the spring presses the lubricant coating brush against the image carrier. The spring pressure detecting unit calculates the torque of the driving unit that drives the lubricant coating brush, and detects the pressing force of the spring based on the calculated torque. Any one of claims 2 to 4. The image forming apparatus according to. The method according to any one of claims 2 to 5, wherein the spring pressure detecting unit calculates the sliding distance of the lubricant-applied brush and detects the pressing force of the spring based on the calculated sliding distance. Image forming device. The method according to any one of claims 2 to 6, wherein the spring pressure detecting unit calculates the sliding time of the lubricant-applied brush and detects the pressing force of the spring based on the calculated sliding time. Image forming device. The spring pressure detecting unit calculates the number of sheets on which an image is formed by the image carrier, and detects the pressing force of the spring based on the calculated number of sheets, according to any one of claims 1 to 7. The image forming apparatus according to item 1. The image forming apparatus according to any one of claims 1 to 4, wherein the spring pressure detecting unit is a pressure sensor that detects a pressing force of the spring. The spring pressure detecting unit calculates the amount of lubricant applied to the image carrier, and detects the pressing force of the spring based on the calculated amount of lubricant, according to any one of claims 1 to 7. The image forming apparatus according to. Any of claims 1 to 10, wherein the control unit notifies that the spring is replaced as the predetermined process when the pressing force of the spring detected by the spring pressure detection unit becomes equal to or less than a threshold value. The image forming apparatus according to item 1. The control unit controls the drive of the image carrier and the drive of the lubricant coating unit, and when the pressing force of the spring detected by the spring pressure detection unit becomes equal to or less than a threshold value, the image is processed as the predetermined process. The image forming apparatus according to any one of claims 1 to 10, wherein the drive of at least one of the drive of the carrier and the drive of the lubricant coating portion is changed. Further equipped with an environmental sensor capable of detecting at least one of the temperature and humidity of the environment in which the image forming apparatus is installed.
The image forming apparatus according to any one of claims 1 to 12, wherein the spring pressure detecting unit corrects the pressing force of the spring according to the result detected by the environmental sensor. 11. Claim 11 or claim, further comprising an environmental sensor capable of detecting at least one of the temperature and humidity of the environment in which the image forming apparatus is installed, and changing the threshold value according to the result detected by the environmental sensor. Item 12. The image forming apparatus according to item 12. The image forming according to any one of claims 5 to 7, wherein the spring pressure detecting unit clears a counter for counting a value required for calculation each time the pressing force of the spring is detected. apparatus. The control unit prohibits image formation on the seat when the pressing force of the spring detected by the spring pressure detection unit is equal to or less than a predetermined value, according to any one of claims 1 to 15. The image forming apparatus according to the description.

Images