Image formation device, and image formation device control method

Abstract

To prevent occurrence of a difference in an electrical characteristic of a surface of an image carrier in a rotating direction of the image carrier such as a photoreceptor drum and the like, when, after the image formation processing is performed, image formation processing has not been performed and an image formation device stays unattended.SOLUTION: According to an environmental measure operation of an image formation device (10) according to the present invention, when, after an ordinary operation such as image formation processing and the like is performed, the ordinary operation has not been performed during a period until a prescribed standby time Ta goes by since the ordinary operation is ended, and a temperature (θ) of outside air is equal to or less than a prescribed temperature threshold (θth), and absolute humidity (ρ) of the outside air is equal to or less than a prescribed humidity threshold (ρth), the photoreceptor drum 42 is rotatingly driven in such a way that a surface of a photoreceptor drum 42 moves a prescribed first distance La.SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present disclosure relates to an image forming apparatus and a control method for the image forming apparatus, and more particularly to an electrophotographic image forming apparatus and a control method for the image forming apparatus. [Background technology]

[0002] This type of image forming apparatus has a photoconductor drum as an image carrier. The electrical characteristics of the surface of the photoconductor drum, such as the charging characteristics, are affected by the temperature and humidity around the photoconductor drum, that is, they are temperature and humidity dependent. One example of a technique for dealing with this is disclosed in Patent Document 1. According to the technique disclosed in Patent Document 1, the conditions of the image forming process are controlled according to information about the temperature and humidity around the photoconductor drum. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-65035 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, a toner image is formed on the surface of the photosensitive drum, and this toner image is transferred to a sheet-like image recording medium such as paper, and then the surface of the photosensitive drum is cleaned by a cleaning device. The cleaning device is provided so as to contact the surface of the photosensitive drum, and has a cleaning blade as a cleaning member for removing deposits including residual toner adhering to the surface of the photosensitive drum, a storage chamber for storing the deposits removed by the cleaning blade, and a transport member for transporting the deposits stored in the storage chamber to a deposit collection container. In particular, the storage chamber is an elongated space extending along the rotation axis direction of the photosensitive drum, and has an opening extending along the rotation axis direction of the photosensitive drum. This opening faces the surface of the photosensitive drum, and the deposits removed by the cleaning blade are stored in the storage chamber through the opening. In addition, the opening is sealed by a sheet-like sealing member provided so as to contact the surface of the photosensitive drum and the cleaning blade in order to prevent the deposits in the storage chamber from scattering to the outside through the opening. Therefore, the containment chamber is in a simply (lightly) sealed state, and is, so to speak, a substantially sealed space.

[0005] Generally, outside air is naturally or forcibly taken into the in-machine space, which is the internal space of the image forming apparatus. For example, after the image forming process is performed by the image forming apparatus, the image forming apparatus is left for a while without performing the image forming process. In this case, the temperature and humidity of the in-machine space, strictly speaking, the temperature and humidity of the in-machine space excluding the storage chamber, becomes close to the temperature and humidity of the outside air in a relatively short time. In contrast, since the storage chamber is a substantially sealed space as described above, it takes a reasonable amount of time for the temperature and humidity of the storage chamber to become close to the temperature and humidity of the outside air. Therefore, after the image forming process is performed (ended), the temperature and humidity of the storage chamber and the temperature and humidity of the in-machine space excluding the storage chamber are in a state of being separated from each other for a while. Also, when the image forming process is not performed, the photosensitive drum does not rotate, so a part of the surface of the photosensitive drum faces the storage chamber, which is a substantially sealed space, and the other part faces (is exposed) to the in-machine space excluding the storage chamber. As a result, in the rotational (circumferential) direction of the photoconductor drum, differences occur in the seasoning (adaptation to the surrounding environment) state of the surface of the photoconductor drum, which in turn causes differences in the electrical characteristics of the surface of the photoconductor drum. If an image formation process is performed again in this state, density unevenness occurs in the toner image formed on the surface of the photoconductor drum, and this density unevenness naturally appears in the so-called output image that is finally formed by the image formation process. This problem is more likely to occur the lower the temperature and humidity of the outside air is.

[0006] Therefore, an object of the present disclosure is to provide a novel image forming apparatus and a control method for an image forming apparatus that can prevent differences in the electrical characteristics of the surface of an image carrier from occurring in the direction of rotation of the image carrier when, after an image formation process has been performed (strictly speaking, including the image formation process), a predetermined operation involving the rotational driving of an image carrier such as a photosensitive drum has been performed, and the image forming apparatus is left for a while without performing the predetermined operation. [Means for solving the problem]

[0007] To achieve this object, the present disclosure includes a first disclosure related to an image forming apparatus and a second disclosure related to a control method for the image forming apparatus.

[0008] The first disclosure of the image forming apparatus is based on the premise that the image forming apparatus is an electrophotographic apparatus, and includes an image forming means, a cleaning member, a storage chamber, an environment detection means, and a control means. The image forming means includes an image carrier that is driven to rotate in a predetermined direction, and forms a toner image on the surface of the image carrier, and transfers the toner image formed on the surface of the image carrier to a sheet-like image recording medium. The cleaning member contacts the surface of the image carrier and removes any deposits that remain on the surface of the image carrier after the toner image has been transferred to the image recording medium. The storage chamber is a space that stores the deposits removed by the cleaning member, and has an opening extending along the rotation axis direction of the image carrier. This opening faces the surface of the image carrier, and the deposits removed by the cleaning member are stored in the storage chamber through the opening. The opening is sealed by the cleaning member and a sheet-like sealing member that contacts the surface of the image carrier. Therefore, the storage chamber is simply sealed, and is, so to speak, a substantially sealed space. The environment detection means detects the temperature and relative humidity outside the storage chamber, for example, outside the image forming apparatus. Then, the control means performs a first control process when a predetermined operation involving the rotational driving of the image carrier is performed, in other words, when the detection result by the environment detection means satisfies a predetermined condition after the predetermined operation is completed, and the predetermined operation is not performed within a first predetermined time period from the time the predetermined operation is completed. In this first control process, the image carrier is rotationally driven so that the surface of the image carrier moves a first predetermined distance in the rotational direction of the image carrier.

[0009] In addition, if a specified operation is not performed between the time when the first control process is ended and the time when a specified second time has elapsed, the control means may repeat a re-control process in which the first control process is performed again a specified number of times unless the specified operation is performed.

[0010] The storage unit may also include a transport member. This transport member transports the deposits stored in the storage chamber to the deposit collection container. Then, if the predetermined operation is not performed even after a predetermined third time has elapsed after repeating the above-mentioned re-control process a predetermined number of times, the control means may perform a second control process. In this second control process, the deposits stored in the storage chamber are transported to the deposit collection container by the transport member.

[0011] Furthermore, the storage chamber may include a discharge port through which the deposit transported by the transport member is discharged into the deposit collection container, and an opening / closing member that opens and closes the discharge port. In this case, it is preferable that the control means keeps the opening / closing member in an open state until the second control process is performed, and closes the opening / closing member after the second control process is performed.

[0012] In addition, the control means may perform a third control process if the predetermined operation is not performed before a fourth predetermined time has elapsed since the opening / closing member was closed. In this third control process, the image carrier is rotationally driven so that the surface of the image carrier moves a second predetermined distance in the rotation direction of the image carrier.

[0013] The predetermined condition in this first disclosure includes, for example, that the absolute humidity derived from the temperature and relative humidity detected by the environment detection means is equal to or lower than a predetermined humidity threshold, and that the temperature is equal to or lower than a predetermined temperature threshold.

[0014] The temperature threshold here is, for example, 10°C, and the humidity threshold is, for example, 1g / m 3 It is.

[0015] The first distance is greater than the dimension of the opening of the storage chamber in at least the rotation direction of the image carrier.

[0016] The second disclosure of the present disclosure, which relates to a control method for an image forming apparatus, is premised on the image forming apparatus being an electrophotographic apparatus. Here, the image forming apparatus includes an image forming means, a cleaning member, a storage chamber, and an environment detection means. The image forming means includes an image carrier that is rotationally driven in a predetermined direction, and forms a toner image on the surface of the image carrier, and transfers the toner image formed on the surface of the image carrier to a sheet-like image recording medium. The cleaning member contacts the surface of the image carrier and removes any deposits that are attached to the surface of the image carrier after the toner image has been transferred to the image recording medium. The storage chamber is a space that stores the deposits removed by the cleaning member, and has an opening extending along the rotation axis direction of the image carrier. This opening faces the surface of the image carrier, and the deposits removed by the cleaning member are stored in the storage chamber through the opening. In addition, the opening is sealed by the cleaning member and a sheet-like sealing member that contacts the surface of the image carrier. Therefore, the storage chamber is simply sealed, and is, so to speak, a substantially sealed space. The environment detection means detects the temperature and relative humidity outside the storage chamber, for example, outside the image forming apparatus. In addition, the second disclosure includes a control step. In this control step, after a predetermined operation involving the rotational driving of the image carrier is performed, in other words, after the predetermined operation is completed, if the detection result by the environment detection means satisfies a predetermined condition and the predetermined operation is not performed within a predetermined first time period from the time the predetermined operation is completed, a first control process is performed. In this first control process, the image carrier is rotationally driven so that the surface of the image carrier moves a predetermined first distance in the rotational direction of the image carrier. Effect of the Invention

[0017] According to the present disclosure, when an image forming device is left for a while without performing a specified operation involving rotational driving of an image carrier after the specified operation involving rotational driving of an image carrier is performed, it is possible to prevent differences in the electrical characteristics of the surface of the image carrier from occurring in the direction of rotation of the image carrier. [Brief description of the drawings]

[0018] [Figure 1]FIG. 1 is a diagram illustrating an outline of the internal configuration of an image forming apparatus according to a first embodiment of the present disclosure. [Diagram 2] FIG. 2 is an enlarged view showing a part of the image forming unit of the image forming apparatus according to the first embodiment. [Diagram 3] FIG. 3 is a block diagram showing the electrical configuration of the image forming apparatus according to the first embodiment. [Figure 4] FIG. 4 is a perspective view of a portion including a photosensitive drum and a cleaning device in the image forming apparatus according to the first embodiment. [Diagram 5] FIG. 5 is a perspective view of the configuration shown in FIG. 4 with the photoconductor drum removed. [Figure 6] FIG. 6 is a diagram showing a schematic internal configuration of a portion including a photosensitive drum and a cleaning device in the image forming apparatus according to the first embodiment. [Figure 7] FIG. 7 is a diagram for explaining the problem to be solved in the first embodiment. [Figure 8] FIG. 8 is a diagram showing an absolute humidity table that serves as a reference when explaining the environmental countermeasure implementation conditions in the first embodiment. [Figure 9] FIG. 9 is a diagram for explaining the environmental countermeasure operation in the first embodiment. [Figure 10] FIG. 10 is a flow diagram showing the flow of environmental measure tasks in the first embodiment. [Figure 11] FIG. 11 is a diagram for explaining the environmental countermeasure operation in the second embodiment of the present disclosure. [Figure 12] FIG. 12 is a flow diagram showing the flow of a part of the environmental measure task in the second embodiment. [Figure 13] FIG. 13 is a block diagram showing the electrical configuration of an image forming apparatus according to the third embodiment of the present disclosure. [Figure 14] FIG. 14 is a flow diagram showing the flow of a part of the environmental measure task in the third embodiment. [Figure 15] FIG. 15 is a diagram for explaining the environmental countermeasure operation in the fourth embodiment of the present disclosure. [Figure 16]FIG. 16 is a flow diagram showing the flow of a part of the environmental measure task in the fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] [First Example] The first embodiment of the present disclosure will be described using an image forming apparatus 10 shown in FIG. 1 as an example.

[0020] The image forming apparatus 10 according to the first embodiment is a so-called multifunction peripheral (MFP) having multiple functions such as a copy function, a printer function, an image scanner function, and a fax function. FIG. 1 is a diagram showing the internal configuration of the image forming apparatus 10 installed in a usable state, as viewed from the front side of the image forming apparatus 10. That is, the up-down direction in FIG. 1 corresponds to the up-down direction of the image forming apparatus 10. And the left-right direction in FIG. 1 corresponds to the left-right direction of the image forming apparatus 10. Furthermore, the front side of the paper surface of FIG. 1 corresponds to the front of the image forming apparatus 10. And the back side of the paper surface of FIG. 1 corresponds to the rear of the image forming apparatus 10.

[0021] An image reading section 12 is provided at the top of the image forming apparatus 10 as an image reading means. The image reading section 12 performs image reading processing by reading an image of an original (not shown) and outputting two-dimensional read image data corresponding to the image of the original. For this purpose, the image reading section 12 has an original table 14 on which an original is placed. The original table 14 is formed of a transparent member such as glass having a roughly rectangular flat plate shape, and is provided so that both main surfaces are aligned in the horizontal direction. An image reading unit 16 is provided below the original table 14. Although detailed explanation is omitted, the image reading unit 16 has a light source, a mirror, a lens, a line sensor, etc., and forms a linear image reading section Pr extending along the front-rear direction of the image forming apparatus 10. Furthermore, a drive mechanism (not shown) for moving (scanning) the image reading section Pr of the image reading unit 16 along the left-right direction of the image forming apparatus 10 is provided below the original table 14. That is, with a document placed on document table 14, an image of the document is read by moving image reading section Pr of image reading unit 16 by a drive mechanism. Also, above document table 14, document pressing cover 18 for pressing down the document placed on document table 14 is provided. The front-to-rear direction of image forming device 10 is called the main scanning direction. And the left-to-right direction of image forming device 10 is called the sub-scanning direction.

[0022] An image forming unit 20, which is an example of an image forming means, is provided below the image reading unit 12. This image forming unit 20 performs image formation processing (printing processing) for forming an image based on appropriate image data, such as the above-mentioned read image data, on a sheet-like image recording medium (not shown), such as paper. This image formation processing is performed by a known electrophotographic method. Moreover, the image forming unit 20 employs a tandem method in order to perform color image formation processing.

[0023] Specifically, the image forming section 20 has four image forming stations (sometimes called "process units") 22, 22, ... as monochrome image forming means for individually forming monochrome toner images of a plurality of different colors, for example, four colors of yellow (Y), magenta (M), cyan (C), and black (K). In addition, the image forming section 20 has an exposure device 24 as an exposure means for performing exposure necessary for forming monochrome toner images by each image forming station 22, 22, .... Furthermore, the image forming section 20 has a transfer unit 26 as a transfer means for sequentially transferring each monochrome toner image formed by each image forming station 22, 22, ... onto an intermediate transfer belt 32 described later, and transferring the toner image transferred onto the intermediate transfer belt 32 onto a paper (sheet). In addition, the image forming section 20 has a fixing device 28 as a fixing means for fixing the toner image transferred onto the paper onto the paper.

[0024] First, a detailed description will be given of the transfer unit 26. The transfer unit 26 includes an intermediate transfer belt (sometimes called a "primary transfer belt") 32, a drive roller 34 that rotates the intermediate transfer belt 32, a driven roller 36 that stretches the intermediate transfer belt 32 together with the drive roller 34, four intermediate transfer rollers (sometimes called "primary transfer rollers") 38, 38, ... provided at positions corresponding to the image forming stations 22, 22, ... on the inside of the intermediate transfer belt 32, and a transfer roller 40 (sometimes called a "secondary transfer roller").

[0025] The intermediate transfer belt 32 is stretched by a driving roller 34 and a driven roller 36. The driving roller 34 rotates by receiving a driving force from a belt motor as a belt driving means (not shown), for example, counterclockwise in FIG. 1. Accordingly, the intermediate transfer belt 32 moves (runs) in a circular motion, and the driven roller 36 rotates. A lower region 32a of the intermediate transfer belt 32 between the driving roller 34 and the driven roller 36 is stretched along the horizontal direction, and the image forming stations 22, 22... are arranged so as to face the region 32a stretched along the horizontal direction. The region 32a of the intermediate transfer belt 32 where the image forming stations 22, 22... are arranged is called an intermediate transfer region. In the intermediate transfer region 32a, the intermediate transfer belt 32 moves from the left side to the right side of the image forming apparatus 10, that is, moves along the sub-scanning direction.

[0026] The intermediate transfer belt 32 is a flexible endless belt-like body made of synthetic resin (e.g., polyimide or polycarbonate) appropriately mixed with conductive materials such as carbon black. Although not described in detail, the driven roller 36 also has the function of preventing the intermediate transfer belt 32 from slackening by applying an appropriate tension to the intermediate transfer belt 32.

[0027] The image forming stations 22, 22, ... are provided at regular intervals below the intermediate transfer region 32a of the intermediate transfer belt 32 along the moving direction of the intermediate transfer belt 32 in the intermediate transfer region 32a, that is, along the sub-scanning direction. As described above, each of the image forming stations 22, 22, ... forms single-color toner images of four colors, yellow, magenta, cyan, and black, on the intermediate transfer belt 32 individually. Here, the image forming stations 22, 22, ... are provided in the order of yellow, magenta, cyan, and black from the upstream side to the downstream side of the moving direction of the intermediate transfer belt 32 in the intermediate transfer region 32a (from the left side to the right side in FIG. 1). The arrangement order of the image forming stations 22, 22, ... is not limited to this. The image forming stations 22, 22, ... have the same structure as each other except that they form single-color toner images of different colors on the intermediate transfer belt 32.

[0028] Referring also to Figure 2, each image forming station 22 (in Figure 2, image forming station 22(K) for black) has a photosensitive drum 42 as an example of an image carrier, a charging device 44 as a charging means, a developing device 46 as a developing means, a cleaning device 48 as a cleaning means, a static elimination device (not shown) as a static elimination means, and the like.

[0029] The photosensitive drum 42 has a base, which is a cylindrical conductive member made of a conductive material such as aluminum. A photosensitive layer is formed on the surface (outer circumferential surface) of this base. The photosensitive layer exhibits conductivity in the portion irradiated with light, and exhibits insulation in the portion not irradiated with light. The photosensitive drum 42 is provided so that the surface of the base is in contact with the outer surface of the intermediate transfer belt 32. The photosensitive drum 42 receives a driving force from a drum motor 43 (see FIG. 00) as a drum driving means and rotates, for example, clockwise in FIG. 2. The photosensitive drum 42 rotates at a speed that matches the moving speed of the intermediate transfer belt 32, and strictly speaking, the peripheral speed of the surface of the base rotates at a speed slightly slower than the moving speed of the intermediate transfer belt 32, for example, about 0.1% to 0.3%. This is to make it easier for the monochrome toner image formed (carried) on the surface of the photosensitive drum 42 to be transferred to the outer surface of the intermediate transfer belt 32; in other words, to prevent the phenomenon in which the monochrome toner image is not transferred from the surface of the photosensitive drum 42 to the outer surface of the intermediate transfer belt 32, such as the phenomenon of characters being hollowed out.

[0030] The charging device 44 has a charging roller 50, and charges the surface of the photosensitive drum 42 to a predetermined potential by a contact charging method using the charging roller 50. That is, the charging roller 50 is provided with its surface in contact with the surface of the photosensitive drum 42, and rotates by receiving a driving force from the drum motor 43 described above via an appropriate gear as a charging roller driving force transmission means (not shown), and more specifically, rotates in the opposite direction to the rotation direction of the photosensitive drum 42, that is, counterclockwise in FIG. 2. The charging roller 50 charges the surface of the photosensitive drum 42 to a predetermined potential by receiving a charging bias from a charging power source (not shown). The charging roller 50 may be configured to rotate by receiving a driving force by contacting the photosensitive drum 42, rather than by receiving a driving force via the charging roller driving force transmission means.

[0031] The surface of the photoconductor drum 42 charged by the charging device 44 is exposed by the exposure device 24. That is, the exposure device 24 irradiates the surface of the photoconductor drum 42 with light in a manner corresponding to the image data used in the image forming process. As a result, an electrostatic latent image in a manner corresponding to the image data used in the image forming process is formed on the surface of the photoconductor drum 42. The exposure device 24 is a laser scanning unit having a laser diode (not shown) as a light source and a polygon mirror as a deflection means, and is provided below the row of image forming stations 22, 22, .... The exposure device 24 irradiates the surface of the photoconductor drum 42 of each image forming station 22 with laser light, for example, from below. As the exposure device 24, instead of a laser scanning unit, an LED unit having an LED array in which LEDs are arranged as a light source may be adopted.

[0032] The surface of the photosensitive drum 42 on which the electrostatic latent image is formed in this manner is developed by the developing device 46. That is, the developing device 46 develops the electrostatic latent image formed on the surface of the photosensitive drum 42 by attaching toner (not shown) charged to the same polarity as the surface potential of the photosensitive drum 42 to the electrostatic latent image formed on the surface of the photosensitive drum 42, thereby visualizing the electrostatic latent image into a monochromatic toner image. For this purpose, the developing device 46 has a stirring and conveying member 52 that stirs and conveys the toner-containing developer (not shown) in the developing device 46 to charge the developer, and a developing roller 54 that conveys the charged developer to the vicinity of the surface of the photosensitive drum 42. The developing roller 54 receives a driving force from the drum motor 43 described above via an appropriate gear as a developing roller driving force transmission means (not shown) and rotates, specifically, in the opposite direction to the rotation direction of the photosensitive drum 42, that is, counterclockwise in FIG. 2. In addition, an appropriate developing bias is supplied to the developing roller 54 from a developing bias power source (not shown). The stirring and conveying member 52 is a so-called auger screw, and receives a driving force from the drum motor 43 via an appropriate gear as a stirring member driving force transmission means (not shown) to rotate in an appropriate direction. The developer referred to here is, for example, a two-component type, but may also be a one-component type.

[0033] The monochrome toner image visualized by development by this developing device 46 is intermediately transferred (primary transfer) from the surface of the photosensitive drum 42 to the outer surface of the intermediate transfer belt 32 by the intermediate transfer roller 38 at the position where the surface of the photosensitive drum 42 and the outer surface of the intermediate transfer belt 32 contact each other.

[0034] Each intermediate transfer roller 38, 38, ... is provided corresponding to each image forming station 22, 22, ..., and each intermediate transfer roller 38 is provided so as to face the photoconductor drum 42 of the image forming station 22 corresponding to it with the intermediate transfer belt 32 interposed therebetween in the intermediate transfer area 32a. Each intermediate transfer roller 38 is provided so as to abut its surface (outer circumferential surface) against the inner surface of the intermediate transfer belt 32. Each intermediate transfer roller 38 rotates by receiving a driving force caused by the circulating movement of the intermediate transfer belt 32, for example, rotating counterclockwise in FIG. 2. Then, a predetermined intermediate transfer bias is applied to each intermediate transfer roller 38 from an intermediate transfer power source (not shown). As a result, static electricity is applied from the intermediate transfer roller 38 to the intermediate transfer belt 32, and a transfer electric field is formed between the surface of the photoconductor drum 42 and the outer surface of the intermediate transfer belt 32. Due to the action of this transfer electric field, a single-color toner image is transferred from the surface of the photoconductor drum 42 to the outer surface of the intermediate transfer belt 32.

[0035] As a result, four single-color toner images of yellow, magenta, cyan, and black are formed individually on the intermediate transfer belt 32. These four single-color toner images are superimposed on one another to form a color toner image on the intermediate transfer belt 32.

[0036] After the single-color toner image is transferred from the surface of the photoconductor drum 42 of each image forming station 22 onto the intermediate transfer belt 32 in this manner, the surface of the photoconductor drum 42 is cleaned by the cleaning device 48. This cleaning device 48 will be described in detail later.

[0037] After being cleaned by the cleaning device 48, the surface of the photoconductor drum 42 is neutralized by a neutralization device (not shown) to erase the potential distribution formed on the surface of the photoconductor drum 42 during the formation of the electrostatic latent image. After that, the process following charging by the charging device 44 is repeated.

[0038] The color toner image formed on the intermediate transfer belt 32 is transferred to a sheet at a transfer nip portion, which is a contact portion between the intermediate transfer belt 32 and the transfer roller 40. Specifically, the transfer roller 40 is provided so as to contact the intermediate transfer belt 32 on the drive roller 34. The transfer roller 40 rotates by receiving a driving force caused by the rotation of the intermediate transfer belt 32, for example, clockwise in FIG. 2. Then, a predetermined transfer bias having a polarity opposite to the charge polarity of the toner is supplied to the transfer roller 40 from a transfer power source (not shown). This forms a transfer electric field between the intermediate transfer belt 32 and the transfer roller 40. In this state, when a sheet passes through the transfer nip portion between the intermediate transfer belt 32 and the transfer roller 40, the toner image formed on the intermediate transfer belt 32 is transferred to the sheet.

[0039] 1, inside the image forming apparatus 10, a paper (sheet) transport path 62 is provided that leads from a paper feed unit 56, which will be described later, to a paper discharge outlet 60 for a paper discharge tray 58 via the transfer nip portion described above. A plurality of transport rollers (strictly speaking, roller pairs) 64, 64, ... are provided at appropriate positions on the paper transport path 62 for transporting paper along the paper transport path 62 from the paper feed unit 56 toward the paper discharge outlet 60. Among the transport rollers 64, 64, ..., a transport roller 64a provided upstream of the transfer nip portion in the paper transport direction on the paper transport path 62 and closest to the transfer nip portion is a registration roller (sometimes called a "paper stop roller") that times the paper to enter the transfer nip portion. Furthermore, among the respective conveying rollers 64, 64, ..., the conveying roller 64b, which is provided at the most downstream side in the paper conveying direction in the paper conveying path 62, i.e., near the paper discharge outlet 60, is a paper discharge roller for discharging paper to the paper discharge tray 58 via the paper discharge outlet 60.

[0040] The fixing device 28 is provided at an appropriate position between the transfer nip portion and the paper discharge port 60 in the paper transport path 62, in other words, at a position downstream of the transfer nip portion in the paper transport path 62 in the paper transport direction. The fixing device 28 has a heat roller 66 and a pressure roller 68. The heat roller 66 and the pressure roller 68 are provided so that their surfaces (outer circumferential surfaces) are in close contact with each other. The heat roller 66 is heated to a predetermined temperature (fixing temperature). At the same time, the heat roller 66 rotates by receiving a driving force from a fixing motor as a fixing roller driving means (not shown), for example, counterclockwise in FIG. 1. Accordingly, the pressure roller 68 also rotates, that is, clockwise in FIG. 1. The paper that has passed through the transfer nip portion passes through the fixing nip portion, which is the contact portion between the heat roller 66 and the pressure roller 68. As a result, the toner image on the paper is fixed on the paper. With this, a series of image forming processes by the image forming unit 20 is completed.

[0041] The paper (printed matter) after the image forming process is discharged to a paper discharge tray 58 through a paper discharge port 60. The paper discharge tray 58 is provided between the image forming unit 20 and the image reading unit 12, and is provided in a so-called internal space of the image forming apparatus 10. The paper discharge tray 58 may also be provided outside the image forming apparatus 10.

[0042] Furthermore, a paper feed unit 56 serving as a paper feed means is provided at the bottom inside the image forming apparatus 10. The paper feed unit 56 has a paper feed cassette 70, and this paper feed cassette 70 can accommodate a plurality of papers (sheets) in a stacked state. In addition, the paper feed unit 56 has a pickup roller 72. The paper feed unit 56 picks up the papers accommodated in the paper feed cassette 70 one by one with the pickup roller 72, and supplies them to the paper transport path 62.

[0043] FIG. 3 is a block diagram showing the electrical configuration of the image forming apparatus 10. As shown in FIG. 3, the image forming apparatus 10 has a control unit 100. The image reading unit 12, the image forming unit 20, and the paper feed unit 56 are connected to the control unit 100 via a bus 102. The control unit 100 is also connected to an auxiliary storage unit 104, a communication unit 106, an environment detection unit 108, and the like via the bus 102. The image forming apparatus 10 also has various elements such as an operation unit (not shown) in addition to the above, but here, illustration and description of elements not directly related to the gist of the present disclosure, including the operation unit, are omitted. The image reading unit 12, the image forming unit 20, and the paper feed unit 56 are as described above. In particular, the image forming unit 20 has a drum motor 43. The drum motor 43 is, for example, a stepping motor, but is not limited thereto.

[0044] The control unit 100 is an example of a control means that controls the entire image forming apparatus 10. For this purpose, the control unit 100 has a computer, such as a CPU 100a, as a control execution means. In addition, the control unit 100 has a main memory unit 100b as a main memory means that can be directly accessed by the CPU 100a. The main memory unit 100b includes, for example, a ROM and a RAM (not shown). Of these, the ROM stores a control program (firmware) for controlling the operation of the CPU 100a. The RAM constitutes a working area and a buffer area when the CPU 100a executes processing according to the control program.

[0045] The auxiliary storage unit 104 is an example of an auxiliary storage means. In other words, various data such as the above-mentioned scanned image data are appropriately stored in the auxiliary storage unit 104. The auxiliary storage unit 104 has, for example, a hard disk drive (not shown). In addition, the auxiliary storage unit 104 may have a rewritable non-volatile memory such as a flash memory.

[0046] The communication unit 106 is an example of a communication means. That is, the communication unit 106 is responsible for two-way communication processing via a LAN line (not shown). The communication unit 106 may be connected to the LAN line by wire or wirelessly. The communication unit 106 is also responsible for two-way communication processing via a public switched telephone network (not shown).

[0047] The environment detection unit 108 is an example of an environment detection means for detecting an environmental element at the place where the image forming apparatus 10 is installed. The environment detection unit 108 has a temperature sensor 108a as a temperature detection means and a humidity sensor 108b as a relative humidity detection means. The temperature sensor 108a is provided, for example, outside the image forming apparatus 10, specifically, on a side surface of the housing of the image forming apparatus 10. The temperature sensor 108a detects an outside air temperature θ as one of the environmental elements. Similarly, the humidity sensor 108b is also provided, for example, outside the image forming apparatus 10, specifically, on a side surface of the housing of the image forming apparatus 10. The humidity sensor 108b detects an outside air relative humidity φ as another environmental element. The temperature sensor 108a may be provided at an appropriate position inside the image forming apparatus 10, not outside the image forming apparatus 10. Similarly, the humidity sensor 108b may be provided at an appropriate position inside the image forming apparatus 10. The temperature sensor 108a and the humidity sensor 108b are preferably provided in close (approximately the same) positions, but may be provided in positions distant from each other, or each may be provided in a plurality of positions.

[0048] Now, the cleaning device 48 that cleans the surface of the photosensitive drum 42 will be described in detail with reference to Figs. 4 to 6. Fig. 4 is a perspective view of a portion of the image forming station 22 that includes the photosensitive drum 42 and the cleaning device 48. Fig. 5 is a perspective view of a configuration in which the photosensitive drum 42 has been removed from the configuration shown in Fig. 4. Fig. 6 is a diagram that shows a schematic internal configuration of the portion that includes the photosensitive drum and the cleaning device, and more specifically, is a diagram (end view) showing a cross section taken along a plane perpendicular to the front-rear direction near the center in the front-rear direction of the configuration shown in Fig. 4.

[0049] The cleaning device 48 includes a cleaning blade 80 that contacts the surface of the photosensitive drum 42 and scrapes off residual toner remaining on the surface of the photosensitive drum 42, a storage chamber 82 for temporarily storing the toner (waste toner) scraped off by the cleaning blade 80, and a transport member 86 for transporting the waste toner temporarily stored in the storage chamber 82 to an outlet 88b to a waste toner box 84 provided in the image forming apparatus 10. The waste toner box 84 is simply shown in FIGS. 4 and 5, and the waste toner box 84 is detachable from an attachment portion (not shown) provided in the image forming apparatus 10. When the waste toner box 84 is attached to the attachment portion, the waste toner box 84 is coupled to an outlet 88b of an outlet portion 88 provided at the front end of the storage chamber 82. The outlet portion 88 is provided with a shutter 90 as an example of an opening / closing member for opening and closing the outlet 88b. The shutter 90 is mechanically configured to be in an open state when the waste toner box 84 is attached to the attachment portion, and to be in a closed state when the waste toner box 84 is removed from the attachment portion.

[0050] The cleaning blade 80 is a long and narrow plate-like body with a thickness of about 2 mm, made of a material having both appropriate elasticity and appropriate rigidity, such as urethane rubber. The cleaning blade 80 is provided so that its longitudinal direction is aligned with the rotation axis direction of the photoreceptor drum 42, and one side edge along the longitudinal direction is directed in a direction opposite to the rotation direction of the photoreceptor drum 42 (counter direction), and the one side edge is obliquely abutted against the surface of the photoreceptor drum 42, and the other side edge is fixed to the housing 48a of the cleaning device 48 via a metal support member 92. The cleaning blade 80, more precisely, one side edge of the cleaning blade 80 scrapes off the residual toner on the surface of the photoreceptor drum 42. That is, the cleaning blade 80 is an example of a cleaning member that comes into contact with the surface of the photoreceptor drum 42 and removes the deposits that are attached to the surface of the photoreceptor drum 42 after the single-color toner image formed on the surface of the photoreceptor drum 42 is transferred to the intermediate transfer belt 32.

[0051] The storage chamber 82 is an elongated space extending along the rotation axis direction of the photosensitive drum 42. The storage chamber 82 has an opening 82a extending along the rotation axis direction of the photosensitive drum 42, and the opening 82a faces the surface of the photosensitive drum 42. The deposits including waste toner scraped off from the surface of the photosensitive drum 42 by the cleaning blade 80 are stored in the storage chamber 82 through the opening 82a.

[0052] A sealing member 94 is provided to prevent the deposits contained in the storage chamber 82 from scattering outside the storage chamber 82 (cleaning device 48). The sealing member 94 is an elongated sheet-like member with a thickness of about 0.1 mm, made of a material having both moderate flexibility and moderate rigidity, such as PET. The sealing member 94 is provided so that its longitudinal direction is aligned with the rotation axis direction of the photosensitive drum 42, and one side edge along the longitudinal direction is directed in a direction following the rotation direction of the photosensitive drum 42 (follow direction), and the one side edge is obliquely abutted against the surface of the photosensitive drum 42, and the other side edge is fixed to the housing 48a of the cleaning device 48 by a suitable attachment means such as double-sided tape. An appropriate distance D is provided between one side edge of the sealing member 94 and one side edge of the cleaning blade 80, and the portion where the distance D is provided abuts against the opening 82a. That is, the opening 82a is in a sealed state by the cleaning blade 80 and the sealing member 94 (strictly speaking, by gap sealing sponges 96 and 98, which will be described later, in addition to the cleaning blade 80 and the sealing member 94).

[0053] Furthermore, at the front and rear ends of the opening 82a, gap sealing sponges 96 and 98 are provided as gap sealing members for sealing the gaps between these ends and the photoconductor drum 42. Therefore, the accommodation chamber 82 is a simply sealed space, or in other words, a substantially sealed space.

[0054] The diameter (outer diameter) of the photoconductor drum 42 is, for example, 30 mm. The dimension D of the opening 82a in the rotation direction of the photoconductor drum 42, in other words, the dimension D of the portion of the surface of the photoconductor drum 42 that covers the opening 82a in the rotation direction of the photoconductor drum 42, is, for example, about 5 mm.

[0055] The transport member 86 is an auger screw, and is provided so as to extend along the rotation axis direction of the photosensitive drum 42. The transport member 86 receives a driving force from the drum motor 43 described above via an appropriate gear serving as a drive force transmission means for the discharge member (not shown) and rotates, more specifically, rotates so as to transport the waste toner in the storage chamber 82 forward. The waste toner transported by the discharge member 86 is discharged into the waste toner box 84 through a discharge port 88a of the discharge section 88.

[0056] Here, an air vent (not shown) is provided at an appropriate position on the housing of the image forming apparatus 10, and outside air is naturally or forcibly drawn into the interior space 200, which is the internal space of the image forming apparatus 10, through this air vent by a fan (not shown).

[0057] Then, for example, after the image forming process is performed, the image forming apparatus 10 is left for a while without performing the image forming process. In this case, the temperature and humidity of the in-machine space 200, strictly speaking, the temperature and humidity of the in-machine space 200 excluding the storage chamber 82, becomes close to the temperature and humidity θ and φ of the outside air in a relatively short time. In contrast, since the storage chamber 82 is a substantially sealed space as described above, it takes a reasonable amount of time for the temperature and humidity of the storage chamber 82 to become close to the temperature and humidity θ and φ of the outside air. Therefore, for a while after the image forming process is performed (ended), the temperature and humidity of the storage chamber 82 and the temperature and humidity of the in-machine space 200 excluding the storage chamber 82 are in a state of being separated from each other. Also, when the image forming process is not performed, the photosensitive drum 42 does not rotate, so a part of the surface of the photosensitive drum 42 faces the storage chamber 82, which is a substantially sealed space, and the other part faces (is exposed to) the in-machine space 200 excluding the storage chamber 82. Therefore, in the rotational (circumferential) direction of the photoconductor drum 42, there is a risk that the seasoning state of the surface of the photoconductor drum 42 will differ, and thus the electrical characteristics of the surface of the photoconductor drum 42 will differ.

[0058] If an image forming process is performed again in this state, density unevenness occurs in the toner image formed on the surface of the photoconductor drum 42, and naturally, this density unevenness also appears in the output image that is finally formed by the image forming process. This problem may occur not only after the image forming process has been performed, but also after a process involving the rotational driving of the photoconductor drum 42, such as a known process control process (a process for adjusting image density) or a known registration adjustment process (a process for adjusting the timing of forming a single-color toner image by each image forming station 22, 22, ...) has been performed.

[0059] FIG. 7 shows an example of density unevenness occurring in a toner image, which is generated when a solid image is output. The up-down direction in FIG. 7 corresponds to the main scanning direction, and the left-right direction in FIG. 7 corresponds to the sub-scanning direction, i.e., the paper conveying direction. In the output image shown in FIG. 7, a low-density stripe 300 extends along the main scanning direction, and more specifically, two stripes 300 and 300 appear. The dimension of each stripe 300 in the sub-scanning direction, that is, the width dimension D', corresponds to the dimension D of the opening 82a in the rotation direction of the photosensitive drum 42. The distance between these two stripes 300 and 300 in the sub-scanning direction corresponds to the circumference of the photosensitive drum 42. FIG. 7 shows an example of an output image when the temperature and humidity θ and φ of the outside air are extremely lower than the temperature and humidity of the storage chamber 82. Depending on the relationship between the temperature and humidity θ and φ of the outside air and the temperature and humidity of the storage chamber 82, the relationship (high and low) of density between each streak 300 and the other parts (excluding the margins) changes.

[0060] Such inconveniences become more pronounced when the temperature and humidity θ and φ of the outside air are low, specifically when the temperature θ of the outside air is 10°C or lower and the absolute humidity of the outside air (volume absolute humidity: the amount of water vapor contained in the air) ρ is 1g / m 3 The temperature and humidity θ and φ and the absolute humidity ρ have a relationship as shown in Fig. 8, and when the temperature and humidity θ and φ and the absolute humidity ρ fall within the shaded area in Fig. 8, the inconvenience described here is likely to occur.

[0061] To address this inconvenience, according to the first embodiment, after a so-called normal operation involving the rotational driving of the photoconductor drum 42, such as an image forming process, a process control process, or a registration adjustment process, is performed, if the normal operation is not performed during a predetermined waiting time (first time) Ta from the time the normal operation ends, and if the outside air temperature θ is equal to or lower than a predetermined temperature threshold θth (θ≦θth) and the outside air absolute humidity ρ is equal to or lower than a predetermined humidity threshold ρth (ρ≦ρth), an environmental countermeasure operation is performed. The waiting time Ta is, for example, 3 minutes. The temperature threshold θth is, for example, 10° C., and the humidity threshold ρth is, for example, 17 g / m3 It is.

[0062] In this environmental countermeasure operation, as shown in FIG. 9, the photoconductor drum 42 is rotationally driven so that the surface of the photoconductor drum 42 moves a predetermined first distance La (first control process). Thereafter, if the normal operation is not performed before a predetermined re-waiting time (second time) Ta' has elapsed, the photoconductor drum 42 is rotationally driven so that the surface of the photoconductor drum 42 moves the first distance La again (re-control process). Such rotational driving of the photoconductor drum 42 is performed a predetermined number of times N, including the first rotational driving (immediately after the wait time Ta has elapsed), unless a command instructing the execution of the normal operation is accepted. The first distance La is larger than the dimension D of the opening 82a described above, in other words, larger than the dimension D of the portion of the surface of the photoconductor drum 42 that covers the opening 82a (La>D), and is, for example, 20 mm. The re-waiting time Ta' is, for example, equivalent to the wait time Ta described above (Ta=Ta'), that is, 3 minutes. The predetermined number of times N is, for example, 10.

[0063] That is, according to this environmental countermeasure operation, each time the photosensitive drum 42 is rotated once by the first distance La, the portion of the surface of the photosensitive drum 42 that covers the opening 82a is shifted more than the dimension D of the opening 82a. As described above, the diameter of the photosensitive drum 42 is 30 mm, that is, the outer circumference of the photosensitive drum 42 is about 94 mm (≒30×π). Therefore, by rotating the photosensitive drum 42 by the first distance La 10 (=N) times, the photosensitive drum 42 rotates two or more times (=(20 mm×10) / 94 mm). This greatly reduces the influence on the electrical characteristics of the surface of the photosensitive drum 42 caused by the temperature and humidity of the storage chamber 82 and the temperature and humidity of the interior space 200 excluding the storage chamber 82 being in a state of being separated from each other. Furthermore, this environmental countermeasure operation continues for about 30 minutes (≈3 minutes × 10) unless a command to execute a normal operation is received during the operation. After about 30 minutes has elapsed, the temperature and humidity in the storage chamber 82 and the temperature and humidity in the interior space 200 excluding the storage chamber 82 become relatively uniform, and the difference in the electrical characteristics of the surface of the photoconductor drum 42 is sufficiently eliminated.

[0064] If a command to execute the normal operation is received while the environmental countermeasure operation is in progress, the environmental countermeasure operation is forcibly terminated. After that, the normal operation is executed. In this case, the temperature and humidity of the storage chamber 82 are close to those of the interior space 200 excluding the storage chamber 82, or the portion of the surface of the photoconductor drum 42 that covers the opening 82a has moved sufficiently away from the position of the opening 82a, so that no uneven density occurs.

[0065] In order to realize the above-mentioned environmental protection operation, the CPU 100a executes an environmental protection task in accordance with the above-mentioned control program, more precisely, in accordance with the environmental protection program included in the control program. The flow of this environmental protection task is shown in Fig. 10. This environmental protection task is executed in response to the end of a normal operation that involves the rotational driving of the photoconductor drum 42, such as an image formation process, a process control process, or a registration adjustment process.

[0066] According to this environmental measure task, the CPU 100a first checks the temperature θ detected by the temperature sensor 108a and the relative humidity φ detected by the humidity sensor 108b in step S1, and then the CPU 100a advances the process to step S3.

[0067] In step S3, the CPU 100a derives the absolute humidity ρ based on the temperature θ and relative humidity φ confirmed in step S1, more specifically by applying the temperature θ and relative humidity φ to the following formula 1. For this formula 1, a general formula is used in which the amount of saturated water vapor is calculated from the temperature θ (air temperature), and the absolute humidity ρ is calculated using the water vapor partial pressure obtained by multiplying the amount of saturated water vapor by the relative humidity φ. Then, the CPU 100a advances the process to step S5.

[0068] 《Formula 1》 ρ = f(θ,φ)

[0069] In step S5, the CPU 100a judges whether or not a predetermined environmental condition is satisfied. The environmental condition here includes that the temperature θ of the outside air is equal to or lower than a predetermined temperature threshold θth, and that the absolute humidity ρ of the outside air is equal to or lower than a predetermined humidity threshold ρth. That is, the CPU 100a judges that the environmental condition is satisfied when the temperature θ of the outside air is equal to or lower than a predetermined temperature threshold θth and the absolute humidity ρ of the outside air is equal to or lower than a predetermined humidity threshold ρth. In step S5, if the CPU 100a judges that the environmental condition is satisfied (S5: YES), the CPU 100a advances the process to step S7. On the other hand, if the environmental condition is not satisfied (S5: NO), the CPU 100a ends the environmental measure task.

[0070] In step S7, the CPU 100a sets the count value n of a counter (not shown) for counting the number of rotations of the photoconductor drum 42 for the first distance La to an initial value of "1." The counter referred to here is a software counter configured by the CPU 100a, but may also be a hardware counter configured by appropriate hardware elements. After executing step S7, the CPU 100a advances the process to step S9.

[0071] In step S9, the CPU 100a resets and starts a timer for measuring the waiting time Ta. The timer for measuring the waiting time Ta is, for example, a software timer configured by the CPU 100a, but may be a hardware timer configured by appropriate hardware elements. The timer for measuring the waiting time Ta is also used as a timer for measuring the re-waiting time Ta'. After executing step S9, the CPU 300a advances the process to step S11.

[0072] In step S11, the CPU 100a judges whether or not a command to execute the normal operation has been received. If a command to execute the normal operation has not been received (S11: YES), the CPU 100a advances the process to step S13. On the other hand, if a command to execute the normal operation has been received (S11: NO), the CPU 100a ends the environmental countermeasure task. The normal operation is executed by a task other than the environmental countermeasure task.

[0073] In step S13, the CPU 100a judges whether the time measured by the timer for measuring the above-mentioned waiting time Ta has elapsed. If the waiting time Ta has not elapsed (S13: NO), the CPU 100a returns the process to step S11. On the other hand, if the waiting time Ta has elapsed (S13: YES), the CPU 100a advances the process to step S15.

[0074] In step S15, the CPU 100a drives the photosensitive drum 42 to rotate by the first distance La, and more precisely, controls the drum motor 43 to do so. Then, the CPU 100a advances the process to step S17.

[0075] In step S17, the CPU 100a increments the count value n of the counter described above, or more precisely, controls the counter to do so, and then the CPU 100a advances the process to step S19.

[0076] In step S19, the CPU 100a compares the count value n after increment in step S17 with the above-mentioned predetermined number of times N. Here, if the count value n is equal to or less than the predetermined number of times N (n≦N), that is, if the rotational driving of the photosensitive drum 42 for the first distance La has not yet been performed the predetermined number of times N (S19: NO), the CPU 100a returns the process to step S9. On the other hand, if the count value n is greater than the predetermined number of times N (n>N), that is, if the rotational driving of the photosensitive drum 42 for the first distance La has been performed the predetermined number of times N (S19: YES), the CPU 100a ends the environmental countermeasure task. Note that, if the environmental countermeasure task is ended by the rotational driving of the photosensitive drum 42 for the first distance La being performed the predetermined number of times N, the image forming apparatus 10 enters the energy saving mode, that is, the CPU 100a executes another task to achieve this.

[0077] Thus, according to the first embodiment, and particularly according to the environmental countermeasure operation, the photoconductor drum 42 is intermittently driven so that the surface of the photoconductor drum 42 moves intermittently by a predetermined first distance La. This significantly reduces the influence on the electrical characteristics of the surface of the photoconductor drum 42 caused by the temperature and humidity of the storage chamber 82 and the temperature and humidity of the interior space 200 excluding the storage chamber 82 being in a state of being different from each other. As a result, the inconvenience of the appearance of streaks 300 as shown in FIG. 7 is eliminated, and a good output image is obtained.

[0078] In addition, the values ​​of the dimension D of the opening 82a, the temperature threshold θth, the humidity threshold ρth, the waiting time Ta, the re-waiting time Ta', the first distance La, the specified number of times N, etc. in this first embodiment are merely examples and are determined appropriately depending on the specifications and properties of the image forming device 10.

[0079] Moreover, the absolute humidity ρ is derived based on the formula 1, but is not limited to this. For example, a lookup table in which an absolute humidity table as shown in Fig. 8 is digitized may be provided, and the absolute humidity Ha may be derived based on this lookup table, that is, by comparing the temperature θ detected by the temperature sensor 108a and the relative humidity φ detected by the humidity sensor 108b with the lookup table.

[0080] The normal operation in the first embodiment is an example of a predetermined operation according to the present disclosure. And the environmental conditions in the first embodiment are an example of a predetermined condition according to the present disclosure. Furthermore, the waiting time Ta in the first embodiment is an example of a first time according to the present disclosure, and the process of rotating the photoconductor drum 42 by the first distance La immediately after the waiting time Ta has elapsed is an example of a first control process according to the present disclosure. In addition, the re-waiting time Ta' in the first embodiment is an example of a second time according to the present disclosure, and the process of rotating the photoconductor drum 42 by the first distance La immediately after the re-waiting time Ta' has elapsed is an example of a re-control process according to the present disclosure. And the waste toner box 84 is an example of an attachment collection container according to the present disclosure.

[0081] [Second Example] Next, a second embodiment of the present disclosure will be described with further reference to FIGS.

[0082] As described above, the storage chamber 82 is a substantially sealed space, and the storage chamber 82, which is a substantially sealed space, stores deposits including waste toner removed from the surface of the photoconductor drum 42. The deposits stored in the storage chamber 82 tend to aggregate into lumps of a certain size, and therefore have a property that moisture does not easily enter or leave. For this reason, the deposits stored in the storage chamber 82 function as a moisturizing agent or a drying agent, and are a major factor in delaying the seasoning of the surface of the photoconductor drum 42 facing the storage chamber 82. In particular, the lower the absolute humidity ρ of the outside air becomes while the storage chamber 82 is left, the larger the difference between the absolute humidity ρ of the outside air and the absolute humidity of the storage chamber 82 becomes, and the more significant the effect becomes.

[0083] Therefore, in this second embodiment, particularly in the environmental protection operation, if a command to perform the aforementioned normal operation has not yet been received after intermittent driving has been performed a predetermined number of times N, similar to that in the first embodiment, an idling process (second control process) is performed to discharge all of the adhering matter contained in the storage chamber 82 into the waste toner box 84.

[0084] Specifically, as shown in FIG. 11, after the intermittent driving for a predetermined number of times N is completed, it is confirmed for a predetermined confirmation time Tb whether a command to perform a normal operation has been received, and if the command has not been received, the idling process is performed. In this idling process, the photosensitive drum 42 is rotated without an image forming process, so to speak, idling. As a result, the conveying member 86 is rotated, and the deposits in the storage chamber 82 are discharged to the waste toner box 84. This idling process is performed for a specified time R that is necessary and sufficient for all of the deposits in the storage chamber 82 to be discharged to the waste toner box 84. Then, when the idling process is completed, the environmental countermeasure operation is completed. The confirmation time Tb is, for example, several seconds to several tens of seconds, but is not limited thereto.

[0085] In the second embodiment, the CPU 100a also executes the environmental countermeasure task, but following step S19 described above (in FIG. 10), it executes steps S101 to S107 shown in FIG 12. That is, in step S19, if the count value n is greater than the judgment reference value (n>N+1), that is, if the intermittent driving has ended (S19: YES), the CPU 100a advances the process to step S101.

[0086] In step S101, the CPU 100a resets and starts a timer for measuring a confirmation time Tb. The timer for measuring the confirmation time Tb is, for example, a software timer configured by the CPU 100a, but may also be a hardware timer configured by appropriate hardware elements. The CPU 100a then advances the process to step S103.

[0087] In step S103, the CPU 100a determines whether or not a command to perform a normal operation has been received. If a command to perform a normal operation has not been received (S103: YES), the CPU 100a advances the process to step S105. On the other hand, if a command to perform a normal operation has been received (S103: NO), the CPU 100a ends the environmental countermeasure task.

[0088] In step S105, the CPU 100a judges whether the time measured by the timer for measuring the confirmation time Tb has elapsed. If the confirmation time Tb has not elapsed (S105: NO), the CPU 100a returns the process to step S103. On the other hand, if the confirmation time Tb has elapsed (S105: YES), the CPU 100a advances the process to step S107.

[0089] In step S107, the CPU 100a rotates the photoconductor drum 15 for a specified time R, and strictly speaking, controls the drum motor 43 to do so. By executing step S107, the CPU 100a ends the environmental protection task. Then, the image forming apparatus 10 enters the energy saving mode.

[0090] Thus, according to the second embodiment, if a command to execute normal operation has still not been received after the intermittent drive has been performed a predetermined number of times N, similar to the first embodiment, an idling process is performed to discharge all of the deposits contained in the storage chamber 82 into the waste toner box 84. This eliminates the delay in seasoning the surface of the photosensitive drum 42 caused by the deposits contained in the storage chamber 82 functioning as a moisturizer or desiccant, and a good output image can be obtained more reliably.

[0091] The idling process in the second embodiment is an example of a second control process according to the present disclosure, and the confirmation time Tb is an example of a third time according to the present disclosure.

[0092] [Third Example] Next, a third embodiment of the present disclosure will be described with further reference to FIGS.

[0093] According to the second embodiment described above, all of the adhering matter contained in the storage chamber 82 is discharged into the waste toner box 84. However, when the shutter 90 is in the open state, there is a concern that the adhering matter discharged into the waste toner box 84 may function as a moisturizer or desiccant.

[0094] Therefore, in the third embodiment, as shown in Fig. 13, a shutter motor 91 is provided as an opening / closing drive means for opening and closing the shutter 90. The shutter motor 91 is controlled so that the shutter 90 is in a closed state when the above-mentioned idling process is completed, that is, when the environmental countermeasure operation is completed. The shutter motor 91 is provided in the image forming unit 20. The shutter motor 91 is, for example, a DC motor, but is not limited to this.

[0095] In the third embodiment, the CPU 100a also executes the environmental countermeasure task, but executes step S201 shown in Fig. 14 following step S107 in the second embodiment (Fig. 12). That is, in step S107, after the photoconductor drum 15 is rotated for a specified time R, the CPU 100a advances the process to step S201.

[0096] In step S201, the CPU 100a closes the shutter 90, that is, controls the shutter motor 91 to close the shutter 90. By executing step S201, the CPU 100a ends the environmental protection task. Then, the image forming apparatus 10 goes into the energy saving mode.

[0097] In this way, according to the third embodiment, the shutter 90 is closed when the idling process is completed, that is, when the environmental protection operation is completed. This prevents the deposits discharged to the waste toner box 84 from acting as a moisturizer or desiccant, and ensures that a good output image is obtained.

[0098] It should be noted that the shutter 90 that has been set to the closed state is set to the open state when a command instructing the execution of a normal operation is received.

[0099] In the third embodiment, the shutter motor 91 is used as the opening / closing drive means, but instead of this, a suitable drive means other than a motor, such as a solenoid, may be used.

[0100] [Fourth Example] Next, a fourth embodiment of the present disclosure will be described with further reference to FIGS.

[0101] According to the third embodiment described above, after all of the adhering matter contained in the storage chamber 82 has been discharged into the waste toner box 84, the shutter 90 is closed. In the fourth embodiment, however, if a command to perform normal operation has not yet been received after the shutter 90 has been closed, intermittent driving is performed in the same manner as in the first embodiment, or in other words, re-intermittent driving is performed.

[0102] Specifically, as shown in FIG. 15, after the shutter 90 is closed, it is confirmed whether or not a command to perform a normal operation has been received for a predetermined reconfirmation time Tc, and if the command has not been received, re-intermittent driving is performed. In this re-intermittent driving, the photosensitive drum 42 is intermittently rotated so that the surface of the photosensitive drum 42 moves intermittently by a predetermined second distance Lb. Then, this intermittent rotation, that is, the rotation of the photosensitive drum 42 for the second distance Lb, is performed a predetermined number of times M. Note that the re-confirmation time Tc is equivalent to the above-mentioned waiting time Ta, for example, that is, 3 minutes. And the second distance Lb is equivalent to the first distance La, for example, that is, 20 mm. Also, the interval time Tc' of the re-intermittent driving is equivalent to the re-confirmation time Tc (Tc=Tc'), for example, that is, 3 minutes. Furthermore, the predetermined number of times M is equivalent to the predetermined number of times N related to the first intermittent driving, for example, that is, 10. Then, when the re-intermittent driving ends, the environmental protection operation ends.

[0103] In the fourth embodiment, the CPU 100a also executes an environmental countermeasure task, but following step S201 in the third embodiment (FIG. 14), it executes steps S301 to S313 shown in FIG 16. That is, after bringing the shutter 90 into a closed state in step S201, the CPU 100a advances the process to step S301.

[0104] In step S301, the CPU 100a sets the count value m of a counter (not shown) for counting the number of rotations of the photoconductor drum 42 for the second distance Lb to its initial value of "1." The counter here is a software counter configured by the CPU 100a, but may also be a hardware counter configured by appropriate hardware elements. After executing step S301, the CPU 100a advances the process to step S303.

[0105] In step S303, the CPU 100a resets and starts a timer for measuring the reconfirmation time Tc. The timer for measuring the reconfirmation time Tc is, for example, a software timer configured by the CPU 100a, but may be a hardware timer configured by appropriate hardware elements. The timer for measuring the reconfirmation time Tc is also used as a timer for measuring the interval time Tc' of re-intermittent driving. After executing step S303, the CPU 300a advances the process to step S305.

[0106] In step S305, the CPU 100a determines whether or not a command to perform a normal operation has been received. If a command to perform a normal operation has not been received (S305: YES), the CPU 100a advances the process to step S307. On the other hand, if a command to perform a normal operation has been received (S305: NO), the CPU 100a ends the environmental countermeasure task.

[0107] In step S307, the CPU 100a judges whether the time measured by the timer for measuring the above-mentioned reconfirmation time Tc has elapsed. If the reconfirmation time Tc has not elapsed (S307: NO), the CPU 100a returns the process to step S305. On the other hand, if the reconfirmation time Tc has elapsed (S307: YES), the CPU 100a advances the process to step S309.

[0108] In step S309, the CPU 100a drives the photoconductor drum 15 to rotate by the second distance Lb, and more precisely, controls the drum motor 43 to do so. Then, the CPU 100a advances the process to step S311.

[0109] In step S311, the CPU 100a increments the count value m of the counter described above, or more precisely, controls the counter to do so. Then, the CPU 100a advances the process to step S313.

[0110] In step S313, the CPU 100a compares the count value m after the increment in step S311 with the above-mentioned predetermined number of times M. Here, if the count value m is equal to or less than the predetermined number of times M (m≦M), that is, if the rotational driving of the photosensitive drum 42 for the second distance Lb has not yet been performed the predetermined number of times M (S313: NO), the CPU 100a returns the process to step S303. On the other hand, if the count value m is greater than the predetermined number of times M (m>M), that is, if the rotational driving of the photosensitive drum 42 for the second distance Lb has been performed the predetermined number of times M (S313: YES), the CPU 100a ends the environmental countermeasure task. Note that when the environmental countermeasure task is ended by the rotational driving of the photosensitive drum 42 for the second distance Lb being performed the predetermined number of times M, the image forming apparatus 10 enters the energy saving mode.

[0111] Thus, according to the fourth embodiment, if a command to execute normal operation has not yet been received after the shutter 90 has been closed, intermittent driving is performed again. This makes the electrical characteristics of the surface of the photoconductor drum 42 more uniform, resulting in a better output image.

[0112] The values ​​of the second distance Lb, the reconfirmation time Tc, the interval time Tc′, the predetermined number of times M, and the like in the fourth embodiment are merely examples, and are appropriately determined depending on the specifications and properties of the image forming apparatus 10, and the like.

[0113] The reconfirmation time Tc in the fourth embodiment is an example of the 43rd time according to the present disclosure. And the process for realizing the re-intermittent driving in the fourth embodiment is an example of the third control process according to the present disclosure.

[0114] [Other application examples] The above-mentioned embodiments are specific examples of the present invention, and do not limit the technical scope of the present invention. The present invention can be applied to aspects other than these embodiments.

[0115] For example, the discharge member 86 is configured to rotate by receiving a driving force from the drum motor 43, but is not limited to this. A motor may be provided as a rotation drive means dedicated to the discharge member 86, in addition to the drum motor 43. In this case, in the above-mentioned idling process, it is not necessary to rotate the photosensitive drum 42 idly, and it is sufficient that a process for driving only the discharge member 86 is performed for the specified time R instead of the idling process.

[0116] In addition, although the embodiments have been described taking the color image forming apparatus 10 as an example, the present invention can also be applied to a monochrome image forming apparatus. Furthermore, although the image forming apparatus 10 in each embodiment is a multifunction machine, the present invention can also be applied to image forming apparatuses other than the multifunction machine, such as a copier or printer.

[0117] In addition, the present invention is not limited to being provided in the form of an image forming apparatus, but can also be provided in the form of a method for controlling an image forming apparatus. [Explanation of symbols]

[0118] 10. Image forming device 20 … Image forming section 42 ... Photoconductor drum 43 ... Drum motor 48 … Cleaning device 80 … cleaning blade 82 … Containment Room 82a … opening 84 … Waste toner box (container for collecting attached matter) 88a … Discharge port 90 ... Shutter 91 ... Shutter motor 94 … Sealing member 100 ... Control section 100a...CPU 100b … Main memory section 108 ... Environment detection section 108a ... Temperature sensor 108b ... Humidity sensor La … 1st distance Lb…Second distance Ta … waiting time Tb … Confirmation time Tc … Reconfirmation time θ…Temperature θth … Temperature threshold φ … relative humidity ρ … absolute humidity ρth: Humidity threshold

Claims

1. An electrophotographic image forming apparatus, an image forming means including an image carrier that is rotationally driven in a predetermined direction, forming a toner image on the surface of the image carrier, and transferring the toner image formed on the surface of the image carrier onto a sheet-shaped image recording medium; a cleaning member that comes into contact with the surface of the image carrier and removes any deposits that remain on the surface of the image carrier after the toner image has been transferred to the image recording medium; the storage chamber being a space for accommodating the deposit removed by the cleaning member, the storage chamber extending along the rotation axis direction of the image carrier and having an opening facing the surface of the image carrier, the deposit being accommodated through the opening, the opening being in a state of being sealed by the cleaning member and a sheet-like sealing member in contact with the surface of the image carrier; an environmental sensing means for sensing the temperature and relative humidity outside the collection chamber; and an image forming apparatus comprising: a control means for performing a first control process to rotate the image carrier so as to move a surface of the image carrier a predetermined first distance in a rotational direction of the image carrier when, after a predetermined operation involving rotational driving of the image carrier is performed, a detection result by the environment detection means satisfies a predetermined condition and the predetermined operation is not performed within a predetermined first time period from the time the predetermined operation is completed.

2. 2. The image forming apparatus according to claim 1, wherein the control means repeats a re-control process for performing the first control process again a predetermined number of times unless the specified operation is performed if the specified operation is not performed between the time when the first control process is completed and a predetermined second time has elapsed.

3. the storage chamber includes a transport member that transports the deposits stored in the storage chamber to a deposit collection container, 3. The image forming apparatus according to claim 2, wherein the control means performs a second control process in which the adhering matter stored in the storage chamber is transported to the adhering matter collection container by the transport member if the specified operation is not performed even after a specified third time has elapsed after repeating the re-control process the specified number of times.

4. The storage chamber further includes a discharge port through which the deposit transported by the transport member is discharged into the deposit collection container, and an opening / closing member that opens and closes the discharge port, 4. The image forming apparatus according to claim 3, wherein the control unit keeps the opening / closing member in an open state until the second control process is performed, and keeps the opening / closing member in a closed state after the second control process is performed.

5. The image forming apparatus of claim 4, wherein the control means performs a third control process to rotate the image carrier so as to move the surface of the image carrier a predetermined second distance in the rotational direction of the image carrier if the specified operation is still not performed before a predetermined fourth time has elapsed from the time the opening / closing member is closed.

6. 2. The image forming apparatus according to claim 1, wherein the predetermined condition includes that the absolute humidity derived from the temperature and the relative humidity detected by the environment detection means is equal to or lower than a predetermined humidity threshold, and that the temperature is equal to or lower than a predetermined temperature threshold.

7. The humidity threshold is 1 g / m ３ 7. The image forming apparatus according to claim 6, wherein the temperature threshold value is 10 degrees Celsius.

8. The image forming apparatus according to claim 1 , wherein the first distance is greater than a dimension of the opening in at least a rotation direction of the image carrier.

9. A method for controlling an electrophotographic image forming apparatus, comprising: The image forming apparatus includes: an image forming means including an image carrier that is rotationally driven in a predetermined direction, forming a toner image on the surface of the image carrier, and transferring the toner image formed on the surface of the image carrier onto a sheet-shaped image recording medium; a cleaning member that comes into contact with the surface of the image carrier and removes any deposits that remain on the surface of the image carrier after the toner image has been transferred to the image recording medium; the storage chamber being a space for accommodating the deposit removed by the cleaning member, the storage chamber having an opening extending along the rotation axis direction of the image carrier and facing the surface of the image carrier, the deposit being accommodated through the opening, the opening being in a state of being sealed by the cleaning member and a sheet-like sealing member in contact with the surface of the image carrier; and An environment detection means for detecting the temperature and relative humidity outside the recovery chamber, The control method includes a control step of performing a first control process to rotate the image carrier so as to move a surface of the image carrier a predetermined first distance in the rotation direction of the image carrier when, after a predetermined operation involving rotational driving of the image carrier is performed, the detection result by the environment detection means satisfies a predetermined condition and the predetermined operation is not performed within a predetermined first time period from the time the predetermined operation is completed.

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