Image forming apparatus

Abstract

The present disclosure relates to an image forming apparatus capable of performing a supply operation for supplying toner from a supply container detachably mountable to the image forming apparatus, including an image bearing member, a developing member, a developing container, a detection portion, a notification portion, and a controller, the controller is configured to perform control to cause the notification portion to notify a timing at which the toner supply operation is performed when the toner amount detected by the detection portion is less than a threshold value. The controller performs control to set the threshold value as a first threshold value in a case where a print rate after a previous supply operation is equal to or greater than a predetermined print rate, and to set the threshold value as a second threshold value higher than the first threshold value in a case where the print rate is less than the predetermined print rate.

Description

Technical Field

[0001] The present invention relates to a toner container which can be mounted in an image forming apparatus for forming an image on a recording material. Background Art

[0002] Generally, an image forming apparatus of an electrophotographic method forms an image by transferring a toner image formed on the surface of a photosensitive drum to a transfer material as a transfer medium. In addition, as a developer supply (replenishment) method, for example, a process cartridge method or a toner container supply method is known. The process cartridge method is a method in which a photosensitive drum and a developer container are integrally assembled into a process cartridge and the process cartridge is replaced with a new process cartridge when the amount of developer in the developer container is less than a predetermined amount. On the other hand, the toner container supply method is a method in which toner is supplied from a toner container (e.g., a toner pack or a toner bottle) to a developer container when the amount of toner in the developer container is less than a predetermined amount.

[0003] Conventionally, as a toner container supply method, a toner pack method has been proposed in Japanese Patent Application Laid-Open No. 2020-154302. In this method, when the toner amount of the toner in the developing container becomes less than a predetermined amount, a display prompting the user to supply the toner is given, and the user is able to refill the toner by supplying the toner from a toner pack containing the toner therein for refilling to the developing container. At this time, the toner amount of the toner in the developing container is detected by detecting whether there is toner at a predetermined position in the developing container using a sensor or the like as a detection device provided on the image forming device side. The image forming device includes a controller (control device), and the controller (sequence) determines the toner amount of the toner in the developing container based on the result of the detection device.

[0004] However, as in the conventional configuration, when a cycle of using the toner to a predetermined amount of toner and then supplying the toner is repeated, fog due to the toner sometimes occurs. In the conventional toner supply, new (fresh) toner is supplied to the developing container in which the deteriorated toner remains. In the case of supplying the toner, the average number of times (hereinafter referred to as the number of frictions) that the individual toner particles of the toner remaining in the developing container are rubbed is naturally greater than the number of frictions of the toner in the new (fresh) product state.

[0005] Therefore, the number of frictions of the toner remaining in the developing container is greater than the number of frictions during the last supply, so that more degraded toner remains in the developing container. The degraded toner accumulates in the developing container, so as a result, there is a possibility of a large amount of fogging due to toner deterioration. Summary of the invention

[0006] The present invention has been accomplished under the above circumstances. A main object of the present invention is to suppress the occurrence of image defects due to toner degradation.

[0007] In order to solve this problem, the present invention provides the following configuration.

[0008] According to one aspect of the present invention, there is provided an image forming device capable of performing a supply operation for supplying toner from a supply container that can be detachably mounted to the image forming device, the image forming device comprising: an image bearing component configured to carry a toner image and to be rotatable; a developing component configured to supply toner to the image bearing component; a developing container configured to accommodate toner and provided with a supply opening through which toner is supplied; a detecting portion configured to detect the toner amount of the toner accommodated in the developing container; a notifying portion configured to notify the timing of performing the supply operation; and a controller configured to perform control so that the notifying portion notifies the timing of performing the supply operation when the toner amount detected by the detecting portion is less than a threshold value, wherein the controller performs control so that the threshold value is set to a first threshold value when the printing rate after the last supply operation is above a predetermined printing rate, and the threshold value is set to a second threshold value higher than the first threshold value when the printing rate is less than the predetermined printing rate.

[0009] According to another aspect of the present invention, there is provided an image forming apparatus capable of performing a supply operation for supplying toner from a supply container that can be detachably mounted to the image forming apparatus, the image forming apparatus comprising: an image bearing member configured to bear a toner image and capable of rotating; a developing member configured to supply toner to the image bearing member; a developing container configured to contain toner and provided with a supply opening through which toner is supplied; a detecting portion configured to detect a toner amount of the toner contained in the developing container; and a notifying portion. a controller configured to execute control so that the notification part notifies the timing of executing the supply operation when the toner amount detected by the detection part is less than a threshold value; and an environment detection part configured to detect the moisture content in the surrounding environment of the image forming device, wherein the controller executes control so that the threshold is set to a first threshold value when the moisture content detected by the environment detection part is above a predetermined moisture content, and sets the threshold to a fourth threshold value higher than the first threshold value when the moisture content is less than the predetermined moisture content.

[0010] Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 1 is a schematic diagram showing the entire image forming apparatus of Embodiments 1 to 3.

[0012] Figure 2 Parts (a) and (b) of FIG. 1 are a perspective view and a front view, respectively, showing a developing container and a toner package in Embodiments 1 to 3.

[0013] Figure 3 Parts (a) and (b) are respectively Figure 2 Cross-sectional views taken along line 40A-40A and line 40B-40B.

[0014] Figure 4 Part (a) is a perspective view showing the toner package in Embodiments 1 to 3, and Figure 4 Parts (b) to (d) of FIG. 1 are front views each showing a modification of the toner package in Embodiments 1 to 3.

[0015] Figure 5 is a cross-sectional view showing a first remaining toner amount sensor and a second remaining toner amount sensor in Embodiments 1 to 3.

[0016] Figure 6 : is a circuit diagram showing a first remaining toner amount sensor and a second remaining toner amount sensor in Embodiments 1 to 3.

[0017] Figure 7 Parts (a) and (b) are cross-sectional views showing the developing containers in Embodiments 1 to 3 in the case where the remaining toner amounts are different.

[0018] Figure 8 1 is a block diagram showing a control system of the image forming apparatus in Embodiments 1 to 3.

[0019] Fig. 9 Parts (a) to (c) of FIG. 1 are perspective views showing the remaining toner amount panels in Embodiments 1 to 3 in the case where the remaining toner amounts are different.

[0020] Fig.10 Parts (a) and (b) are flowcharts showing a toner supply process and an operation portion in Embodiments 1 to 3, respectively.

[0021] Fig.11 : is a flowchart showing the remaining toner amount detection processing in Embodiments 1 to 3.

[0022] Fig.12 Parts (a) to (c) are each a cross-sectional view showing a state during toner supply.

[0023] Fig.13 1 is a flowchart showing the remaining toner amount display processing in Embodiment 1.

[0024] Fig.14 1 is a flowchart showing the remaining toner amount display processing in the second embodiment.

[0025] Fig.15 1 is a flowchart showing the remaining toner amount display processing in the third embodiment. DETAILED DESCRIPTION

[0026] Hereinafter, the image forming device according to the present invention will be described in detail with reference to the accompanying drawings. However, the size, material, shape, relative arrangement, etc. of the constituent elements described in the following embodiments should be appropriately changed according to the construction and various conditions of the device to which the present invention is applied, and the scope of the present invention should not be limited to the following embodiments.

[0027] In addition, the recording materials used in the image forming apparatus include various sheet materials of different materials, including paper (such as ordinary paper and thick paper), plastic film (such as sheets used for overhead projectors), sheets of special shapes (such as envelopes and index paper), cloth, etc.

[0028] [Overall structure]

[0029] The image forming apparatus 100 of the first embodiment is a monochrome laser beam printer of an electrophotographic method. Figure 1 As shown, a process unit 9 of a direct transfer method is installed in a main assembly M of an image forming apparatus 100. The process unit 9 includes a photosensitive drum 1, and components arranged around the photosensitive drum 1, including a charging roller 2, a developing device 20, a discharging device, and a brush component 12. In addition, the main assembly M of the apparatus includes: a scanner unit 10 for forming an electrostatic latent image by irradiating the photosensitive drum 1 with laser light; and a transfer roller 13 for forming a transfer nip N1 between itself and the photosensitive drum 1 and for transferring a toner image to a recording material P in the transfer nip N1. The transfer roller 13 contacts the surface 1a of the photosensitive drum 1 and transfers the toner image from the photosensitive drum 1. Incidentally, in Embodiment 1, the process unit 9 is configured to be detachably mounted to the main assembly M of the apparatus, but is not limited thereto. For example, the process unit 9 may also be configured to be non-detachably mounted to the main assembly M of the apparatus.

[0030] The photosensitive drum 1 as an image bearing member is rotatable about a rotation axis CP extending in the axial direction J1 (see Figure 2) and is a photosensitive component molded into a cylindrical shape. The photosensitive drum 1 includes a photosensitive layer formed of a negatively chargeable organic photosensitive component on a substrate molded into a drum shape with aluminum. Specifically, the photosensitive drum 1 is a rigid component formed by sequentially applying a resistance layer, a primer layer and a photosensitive layer on the outer peripheral surface of an aluminum cylinder having a diameter of 24 mm by a dip coating method, and the photosensitive layer includes a charge generating layer and a charge transporting layer. The film thickness of the charge transporting layer is 22 μm. In addition, the photosensitive drum 1 is rotationally driven around the rotation axis CP at a predetermined circumferential speed in the direction of the arrow L. The circumferential speed of the photosensitive drum 1 defines the image forming speed of the image forming device 100, and is therefore also referred to as a processing speed.

[0031] The charging roller 2 as a charging component contacts the photosensitive drum 1 with a predetermined pressing force and forms a charging portion N2. In addition, a charging voltage as a DC voltage is applied to the charging roller 2 from a charging voltage applying circuit (not shown), so that the charging roller 2 uniformly charges the surface 1a of the photosensitive drum 1 to a predetermined potential. A charging voltage of -1400V is applied to the charging roller 2 in Example 1 so that the surface potential (pre-exposure potential VD) of the photosensitive drum 1 becomes -800V. That is, the photosensitive drum 1 is charged to the pre-exposure potential VD as the fourth potential in the negative polarity direction of the same polarity as the colorant polarity by the charging roller 2. The charging roller 2 includes a core metal with a diameter of 6 mm, a base layer of epichlorohydrin rubber, and a surface layer of polyurethane, and is constructed to have an outer diameter of 12 mm. In addition, the resistance of the charging roller 2 is 1×10 6 Ω or less, and the hardness of the charging roller 2 measured by the MD-1 rubber hardness meter is 70 degrees. Incidentally, a DC voltage is used as the charging voltage in Embodiment 1, but the charging voltage is not limited thereto. A voltage in the form of a DC voltage superimposed on an AC voltage may be used.

[0032] The scanner unit 10 irradiates the surface 1a of the photosensitive drum 1 with laser light corresponding to the image information input from the external device by using a rotating polygon mirror, thereby performing scanning exposure on the surface 1a of the photosensitive drum 1. Through this exposure, an electrostatic latent image depending on the image information is formed on the surface 1a of the photosensitive drum 1. The scanner unit 10 is a semiconductor laser, and not only irradiates the surface of the photosensitive drum with laser light having a wavelength of 800nm ​​from the laser, but also can change the light amount of the laser light. Incidentally, the scanner unit 10 is not limited to a laser scanner device, but may be, for example, an LED exposure device including an LED array in which a plurality of LEDs are arranged along the longitudinal direction of the photosensitive drum 1.

[0033] The developing device 20 includes a developing container 8 (which serves as a frame for the developing device 20), a developing roller 4, and a supply roller 5 for supplying a developer to the developing roller 4. Inside the developing container 8 as a accommodating portion, a accommodating chamber 8a for accommodating a toner (developer) and a developing chamber 8b including the developing roller 4 are formed. The developing roller 4 and the supply roller 5 are rotatably supported by the developing container 8. In addition, the developing roller 4 is disposed at an opening of the developing container 8 to be opposed to the photosensitive drum 1. The supply roller 5 rotatably contacts the developing roller 4, and the toner (which serves as the developer accommodated in the developing container 8) is applied to the surface of the developing roller 4 by the supply roller 5.

[0034] The developing device 20 uses a contact developing method as a developing method. That is, the toner layer carried on the developing roller 4 contacts the photosensitive drum 1 at the developing portion N3 where the photosensitive drum 1 and the developing roller 4 are opposite to each other. In other words, the developing roller 4, which is a rotatable developing component, forms a developing portion N2 between itself and the photosensitive drum 1. A developing voltage as a DC voltage is applied to the developing roller 4 from a developing voltage applying portion (not shown). When the developing voltage is applied, the toner carried on the developing roller 4 is transferred from the developing roller 4 to the surface 1a of the photosensitive drum 1 according to the potential distribution of the surface 1a of the photosensitive drum 1, so that the electrostatic latent image is developed into a toner image. Incidentally, in Example 1, a reversal developing method is adopted. That is, a toner image is formed by depositing toner on an area of ​​the surface 1a of the photosensitive drum 1 where the charge amount is attenuated by exposure in an exposure step after being charged in a charging step.

[0035] In addition, in Example 1, a toner having a particle size of 6 μm and a normal charged polarity of negative polarity is used. As the toner in Example 1, a polymerized toner formed by a polymerization method is used as an example. In addition, the toner in Example 1 is a so-called non-magnetic single-component developer, which does not contain a magnetic component and in which the toner is carried on the developing roller 4 mainly by intermolecular force or electrostatic force (mirror force). However, a single-component developer containing a magnetic component can also be used. In addition, in the single-component developer, in some cases, in addition to the toner particles, an additive (for example, wax or silica particles) for adjusting the fluidity and charging performance of the toner is also contained. In addition, as a developer, a two-component developer consisting of a non-magnetic toner and a magnetic carrier can also be used. In the case of using a developer having magnetic properties, as a developer carrying member, for example, a cylindrical developing sleeve having a magnet disposed therein is used. In addition, the developing device 20 can be a non-contact developing method, in which the developing device 20 is arranged to have a predetermined gap between itself and the photosensitive drum 1.

[0036] The developing roller 4 was prepared by coating a core metal having a diameter of 6 mm with a base layer of silicone rubber and a surface layer of polyurethane rubber to have an outer diameter of 15 mm. In addition, the resistance value of the developing roller 4 was 1×10 4 Up to 1×10 12 Ω. The supply roller 5 is a conductive elastic sponge roller prepared by forming a foam member on the outer peripheral surface of a core metal having a diameter of 6 mm. In addition, the resistance value of the supply roller 5 is 1×10 4 Up to 1×10 8 Ω and the hardness is 200 gf. The hardness of the supply roller 5 in Example 1 is a value obtained by measuring a load when a flat plate having a longitudinal width (length in the axial direction J1) of 50 mm is made to intrude 1 mm from the surface of the supply roller 5.

[0037] The stirring member 7 is provided inside the developing container 8. By being driven and rotated by the driving motor, the stirring member 7 not only stirs the toner in the developing container 8 but also sends the toner toward the developing roller 4 and the supply roller 5. In addition, the stirring member 7 has a function of circulating the toner that is not used for development and is peeled off from the developing roller 4 in the developing container 8 and making the toner in the developing container 8 uniform.

[0038] A developing blade 6 for controlling the amount of toner carried on the developing roller 4 is provided at the opening of the developing container 8 where the developing roller 4 is provided. As the developing roller 4 rotates, the toner supplied to the surface of the developing roller 4 passes through the portion opposite to the developing blade 6, so that the toner uniformly forms a thin layer and is charged to a negative polarity by friction charging.

[0039] The developing scraper 6 is a 0.1 mm thick SUS metal plate and is arranged to contact the developing roller 4 so that its free end is located on the downstream side of the developing roller 4 with respect to the rotation direction of the developing roller 4. As the developing scraper 6 used in Example 1, a scraper prepared by cutting and processing the end of the SUS metal plate from the contact surface side with the developing roller 4 is used. The free end of the developing scraper 6 is bent in the cutting direction by the cutting process.

[0040] The transfer roller 13 as the transfer portion includes an ion conductive sponge base layer, thereby having an outer diameter of 15 mm relative to a core metal having a diameter of 6 mm. In addition, the resistance value of the transfer roller 13 in a temperature environment of 22° C. is 4×10 7 Ω, and the hardness measured by an Asker-C rubber hardness meter (manufactured by Kobunshi Keiki Co., Ltd.) was 30 degrees.

[0041] [Image forming operation]

[0042] When an image forming instruction is output to the image forming apparatus 100, an image forming process is started based on image information input from an external computer or the like connected to the image forming apparatus 100. When the image forming process is started, the photosensitive drum 1 is driven by a driving source (not shown) and Figure 1 The photosensitive drum 1 is rotated at a predetermined process speed in the direction of arrow L. In Embodiment 1, the process speed of the photosensitive drum 1 is 140 rpm.

[0043] In the process unit 9, a discharge device 11 for discharging the photosensitive drum 1 is provided at the downstream side of the transfer nip N1 and the upstream side of the charging portion N2 with respect to the rotation direction (arrow L direction) of the photosensitive drum 1. Specifically, the discharge device 11 as the discharge portion is provided between the brush member 12 and the charging roller 2 with respect to the rotation direction of the photosensitive drum 1. In order to generate stable discharge at the charging portion N2, the discharge device 11 discharges (eliminates) the surface potential of the photosensitive drum 1 before the surface of the photosensitive drum reaches the charging portion N2.

[0044] Then, the charging roller 2 uniformly charges the surface of the photosensitive drum 1 so that the surface potential (pre-exposure potential VD) of the rotating photosensitive drum 1 becomes -800 V. The scanner unit 10 irradiates the photosensitive drum 1 with laser light based on the input image information. Thus, an electrostatic latent image is formed on the uniformly charged surface 1a of the photosensitive drum 1. In Embodiment 1, the scanner unit 10 uses a light amount of 0.45 J / cm 2 The laser beam irradiates the photosensitive drum surface so that the potential VL of the photosensitive drum 1 after exposure becomes -100V.

[0045] At this time, a toner layer charged to a predetermined polarity is formed on the surface of the developing roller 4. Then, a developing voltage is applied to the developing roller 4 from a developing voltage applying portion (not shown), whereby the electrostatic latent image on the photosensitive drum 1 is developed at the developing portion N3, so that a toner image is formed on the photosensitive drum 1. -400 V is applied to the developing roller 4 as the developing voltage in Embodiment 1.

[0046] In parallel with the above-described image forming process, the recording material P stored at the lower portion of the image forming apparatus 100 is fed. The recording material P is conveyed to the transfer nip N1 in synchronization with the timing at which the toner image formed on the photosensitive drum 1 reaches the transfer nip N1. Furthermore, in synchronization with the timing, a transfer voltage as a DC voltage is applied from a transfer voltage applying circuit (not shown) to the transfer roller 13. Thus, the toner image carried on the photosensitive drum 1 is transferred to the recording material P passing through the transfer nip N1. +1500 V is applied to the transfer roller 13 as the transfer voltage in Embodiment 1.

[0047] The recording material P on which the toner image is transferred is conveyed to the fixing device 14. The fixing device 14 is a thermal fixing method for fixing the image by heating and melting the unfixed toner on the recording material P. The fixing device 14 includes a fixing film 14a, a fixing heater (e.g., a ceramic heater) for heating the fixing film 14a, and a pressure roller 14b that is pressed against the fixing film 14a. When the recording material P passes through the nip between the fixing film 14a and the pressure roller 14b, the toner image is heated and pressurized. As a result, the toner particles melt and then adhere, thereby fixing the toner image on the recording material P. The recording material P that has passed through the fixing device 14 is discharged to the outside of the image forming device 100 by a discharge roller pair (not shown).

[0048] In addition, the image forming apparatus 100 includes an environment detection portion 54 as an environment detection device. The environment detection portion 54 is provided in the image forming apparatus 100 and detects the ambient temperature and humidity. Based on the detection result of the environment detection portion 54, the voltage applied to the charging roller 2 and the developing roller 4 and the control of the scanner unit 10, the transfer roller 13, the fixing device, etc. are corrected.

[0049] [Recovery of transfer residual toner]

[0050] The toner that is not transferred to the recording material P and remains on the photosensitive drum 1 (hereinafter, the toner is referred to as transfer residual toner) is removed in the following steps. After the transfer step, the photosensitive drum 1 reduces the surface potential due to the influence of the transfer voltage applied during the transfer nip N1. In Embodiment 1, the surface potential of the photosensitive drum 1 after the transfer step is -150V. After the transfer step, the photosensitive drum surface is discharged by the discharge device 11 so that the surface potential remaining on the photosensitive drum 1 becomes 0V and rotates toward the charging part N2. In the transfer residual toner, there are toners charged to the positive polarity and toners charged to the negative polarity but not having sufficient charge in the form of a mixture. The transferred photosensitive drum 1 is charged by the discharge device 11 to remove the charge, and the charging roller 2 is uniformly discharged, so that the transfer residual toner is charged to the negative polarity again. The transfer residual toner charged again to the negative polarity at the charging portion N2 reaches the developing portion N3 as the photosensitive drum 1 rotates. Then, the surface area of ​​the photosensitive drum 1 passing through the charging portion N2 is exposed by the scanner unit 10 while being in a state where the transfer residual toner is deposited on the surface, thereby writing (forming) an electrostatic latent image.

[0051] Here, the behavior of the transfer residual toner reaching the developing portion N3 is described by dividing the portion of the photosensitive drum 1 into the exposed portion and the non-exposed portion. The transfer residual toner deposited on the non-exposed portion of the photosensitive drum 1 is transferred to the developing roller 4 at the developing portion N3 by the potential difference between the pre-exposure potential VD of the non-exposed portion of the photosensitive drum 1 and the developing voltage, and is recovered in the developing container 8. This is because, assuming that the normal charging polarity of the toner is negative, the developing voltage applied to the developing roller 4 is positive with respect to the pre-exposure potential VD of the non-exposed portion. Incidentally, the toner recovered in the developing container 8 is stirred and dispersed together with the toner in the developing container 8 by the stirring member 7, and is carried on the developing roller 4, so that these toners are reused in the developing step.

[0052] On the other hand, the transfer residual toner deposited on the exposed portion of the photosensitive drum 1 is not transferred from the photosensitive drum 1 to the developing roller 4 at the developing portion N3, but remains on the surface 1a of the photosensitive drum 1. This is because, assuming that the normal charging polarity of the toner is negative, the developing voltage applied to the developing roller 4 becomes a potential more negative than the pre-exposure potential VD of the exposed portion. The transfer residual toner remaining on the surface 1a of the photosensitive drum 1 is carried on the photosensitive drum 1 together with other toner transferred from the developing roller 4 to the exposed portion, and moves to the transfer nip N1, so that these toners are transferred to the recording material P at the transfer nip N1.

[0053] Therefore, in Embodiment 1, the process unit 9 has a cleaner-less structure in which the transfer residual toner is recovered in the developing device 20 and reused. By making the process unit 9 have a cleaner-less structure, the installation space of the recovery container and the like for recovering the transfer residual toner becomes unnecessary, and further miniaturization of the image forming apparatus 100 becomes possible, and further, a reduction in printing cost can be achieved by reusing the transfer residual toner.

[0054] [Constitution of the developer container and toner pack]

[0055] Next, the configurations of the developing container 8 and the toner package 40 will be described. Figure 2 Part (a) is a perspective view showing the developing container 8 and the toner pack 40, and Figure 2 Part (b) of FIG. 1 is a front view showing the developing container 32 and the toner package 40 . Figure 3 Part (a) is Figure 2 40A-40A cross-sectional view of part (b), and Figure 3 Part (b) is Figure 2 40B-40B cross-sectional view of part (b).

[0056] like Figure 2 Part (a) to Figure 3 As shown in part (b) of the developing container 8, the developing container 8 includes a housing chamber 8a in which the stirring member 7 is provided, and the housing chamber 8a as a housing portion for housing the developer is extended in the longitudinal direction ( Figure 2 The developing container 8 includes a slanted portion 37 which is a protruding portion which protrudes obliquely upward from one end portion in the longitudinal direction of the accommodating chamber 8a and is communicated with the accommodating chamber 8a.

[0057] A mounting portion 57 capable of mounting the toner pack 40 is provided at the upper end portion (top end portion) of the inclined portion 37, and a supply opening 32a for allowing the developer to be supplied from the toner pack 40 to the accommodating chamber 8a is formed at the mounting portion 57. The toner pack 40 can be mounted to the mounting portion 57 in a state where the toner pack 40 is exposed to the outside of the device.

[0058] The developing container 8 is configured so that the toner supplied through the supply opening 32a reaches the stirring member 7 only by its own weight. Here, the term "only by its own weight" means that in the case where the toner is supplied in a state where the developing container 8 is mounted (assembled) in the main assembly, a stirring member (transporting member) that supplies the toner by rotating or swinging is not provided between the supply opening 32a of the developing container 8 and the stirring member 7, but the developing container 8 is configured so that the toner reaches the stirring member 7 only by its own weight. In addition, in the developing container 8, the stirring member 7 is a rotatable member closest to the supply opening 32a and is provided so that the toner in the accommodating chamber 8a reaches the developing roller 4 or the supply roller 5 by its rotation.

[0059] The gripping portion 39 including the tab portion 39a can be gripped by a user hooking the tab portion 39a with his (her) fingers, and the tab portion 39a is formed by protruding upward from the top surface of the gripping portion 39. The inclined portion 37 is formed in a hollow shape inside thereof, and a supply opening 32a is formed on the upper surface. The supply opening 32a is configured to be connectable to the toner pack 40.

[0060] The toner pack 40 is configured to be attachable to and detachable from the mounting portion 57 of the inclined portion 37. In addition, the toner pack 40 includes a shutter member 41 that is provided at the opening and can be opened and closed, and a plurality of (three in this embodiment) protrusions 42 formed corresponding to a plurality of (three in this embodiment) grooves 32b formed at the mounting portion 57. In a case where the user supplies toner to the developing container 8, the user performs alignment so that the protrusions 42 of the toner pack 40 pass through the grooves 32b of the mounting portion 57, so that the user connects the toner pack 40 with the mounting portion 57. Then, when the toner pack 40 is rotated 180 degrees in this state, the shutter member 41 of the toner pack 40 abuts against an abutment portion (not shown) of the mounting portion 57 and rotates relative to the main body of the toner pack 40, so that the shutter member 41 is opened. Thereby, the toner contained in the toner pack 40 leaks downward from the toner pack 40, and the toner leaked downward enters the hollow-shaped inclined portion 37. Incidentally, the shutter member 41 may also be provided on the supply opening 32a side.

[0061] The inclined portion 37 includes an inclined surface 37a at a position opposite to the opening of the supply opening 32a, and the inclined surface 37a is inclined downward toward the accommodation chamber 8a. Therefore, the toner supplied through the supply opening 32a is guided to the accommodation chamber 8 by the inclined surface 37a. Figure 3 As shown, the stirring member 7 includes a stirring shaft 7a extending in the longitudinal direction and a blade portion 7b fixed to the stirring shaft 7a and extending toward the outside in the radial direction compared with the stirring shaft 7a. The blade portion 7b is a flexible thin sheet. The stirring member 7 rotates around the stirring shaft 7a.

[0062] As the stirring member 7 rotates, the toner supplied through the supply opening 32a provided on the upstream side of the (recording material) conveying direction of the stirring member 7 is sent to the developing roller 4 and the supply roller 5. The conveying direction of the stirring member 7 is a direction parallel to the longitudinal direction of the developing container 8. The supply opening 32a and the inclined portion 37 are provided at one end portion in the longitudinal direction of the developing container 8, but the toner is spread over the entire length of the developing container 8 by the repeated rotation of the stirring member 7. Incidentally, in Embodiment 1, the stirring member 7 is composed of the stirring shaft 7a and the blade portion 7b, but as a structure for spreading the toner over the entire length of the developing container 8, a spiral stirring shaft may also be used.

[0063] In Embodiment 1, the toner pack 40 is composed of Figure 4 The toner pack 40 may be made of a plastic bag member that is easily deformed as shown in parts (a) and (b), but the present invention is not limited thereto. Figure 4 The substantially conical bottle container 40B shown in part (c) of the embodiment of the present invention is constituted by a bottle container 40B having a substantially conical shape and can be composed of Figure 4 The toner pack may be composed of a paper container 40C made of paper shown in part (d) of the drawing. In either case, the toner pack may be of any material and shape. In addition, regarding the method of discharging the toner from the toner pack, if the toner pack is the toner pack 40 or the paper container 40C, a method in which the user squeezes the toner pack with fingers is suitable; if the toner pack is the bottle container 40B, a method in which the user causes the toner to leak downward by tapping the container while vibrating the container, etc. is suitable. In addition, in order to discharge the toner from the bottle container 40B, a discharge mechanism may be provided in the bottle container 40B. In addition, the discharge mechanism may be a structure for receiving a driving force from the main component M of the device by engaging with the main component M of the device.

[0064] Furthermore, in any toner pack, the shutter member 41 may be omitted, or a shutter member of a sliding type may be applied instead of the shutter member 41. Furthermore, the shutter member 41 may be a configuration in which the shutter member 41 is broken by mounting the toner pack on the supply opening 32a or by rotating the toner pack in a mounted state, or the shutter member may be a detachable cap structure (e.g., a seal).

[0065] [Method for detecting the amount of residual toner]

[0066] Next, we will use Figures 5 to 7 A method of detecting the remaining toner amount of the developing container 8 is described. In the developing device 30 of Embodiment 1, the first remaining toner amount sensor 51 and the second remaining toner amount sensor 52 are provided, which are detecting means for detecting a state depending on the remaining toner amount in the developing container 8.

[0067] The first remaining toner amount sensor 51 includes a light emitting portion 51 a and a light receiving portion 51 b , and the second remaining toner amount sensor 52 includes a light emitting portion 52 a and a light receiving portion 52 b . Figure 6 : is a circuit diagram showing an example of the circuit structure of the first remaining toner amount sensor 51 and the second remaining toner amount sensor 52. Incidentally, in the following description, the circuit structure of the first remaining toner amount sensor 51 is described, and the description of the circuit structure of the second remaining toner amount sensor 52 will be omitted.

[0068] exist Figure 6In the present invention, an LED is used as the light-emitting part 51a, and a phototransistor placed in an ON state by light from the light-emitting part 51a is used as the light-receiving part 51b, but the present invention is not limited to this. For example, a halogen lamp or a fluorescent lamp can be used as the light-emitting part 51a, and a photodiode or an avalanche photodiode can be used as the light-receiving part 51b. Incidentally, a switch (not shown) is provided between the light-emitting part 51a and the power supply voltage (voltage source) Vcc, and by placing the switch in an ON state, a voltage from the power supply voltage Vcc is applied to the light-emitting part 51a, so that the light-emitting part 51a is in an ON state. On the other hand, the light-receiving part 51b is also provided with a switch (not shown) between itself and the power supply voltage (voltage source) Vcc, and by placing the switch in an ON state, the light-receiving part 51b is in an ON state by a current depending on the amount of light detected.

[0069] The power supply voltage Vcc and the current limiting resistor R1 are connected to the light emitting portion 51a, and the light emitting portion 51a emits light by the current determined by the current limiting resistor R1. The light emitted from the light emitting portion 51a passes through the optical path Q1 and is received by the light receiving portion 51b, as shown in FIG. Figure 5 As shown. The power supply voltage Vcc is connected to the collector terminal of the light receiving portion 51b, and the detection resistor R2 is connected to the emitter terminal. The light receiving portion 51b, which is a phototransistor, receives the light emitted from the light emitting portion 51a and outputs a signal (current) according to the amount of light received. The signal is converted into a voltage V1 by the detection resistor R2 and input to the A / D conversion portion 95 of the controller 90 (see Figure 8 ). Incidentally, the light receiving portion 52b of the second remaining toner amount sensor 52 receives light emitted from the light emitting portion 52a and passing through the optical path Q2, and outputs a voltage V2 according to the amount of received light and the voltage V2 is input to the A / D conversion portion 95 of the controller 90.

[0070] The controller 90 (CPU 91) determines whether the light receiving portions 51b and 52b receive the light from the light emitting portions 51a and 51b based on the input voltage level. The controller 90 calculates the amount of toner in the developing container 8 based on the time length of each light detected by the light receiving portion 51b or 52b and the intensity of the received light when the toner in the developing container 8 is stirred for a certain time by the stirring member 7. That is, the ROM 93 stores in advance a table capable of outputting the amount of remaining toner based on the light receiving time and the light intensity when the toner is fed by the stirring member 7, and the controller 90 predicts / calculates the amount of remaining toner based on the input of the A / D conversion portion 95 and the table.

[0071] More specifically, the optical path Q1 of the first remaining toner amount sensor 51 is set to intersect with the rotation trajectory Tr of the stirring member 7. In addition, the time during which the optical path Q1 is blocked by the toner jumping up by the stirring member 7 when the stirring member 7 rotates one circle (that is, the time during which the light receiving portion 51b cannot detect the light from the light emitting portion 51a) varies according to the remaining toner amount. In addition, the received light intensity at the light receiving portion 51b also varies according to the remaining toner amount.

[0072] That is, when the amount of residual colorant is large, the optical path Q1 is easily blocked by the colorant, and therefore, the time for the light receiving portion 51b to receive light becomes shorter, and the received light intensity of the light received by the light receiving portion 51b becomes smaller. On the other hand, when the amount of residual colorant is small, the time for the light receiving portion 51b to receive light becomes longer, and the received light intensity of the light received by the light receiving portion 51b becomes stronger. Accordingly, as described below, the controller 90 can thereby determine whether the amount of residual colorant is at a low (LOW) level or a medium (MID) level based on the light receiving time and the received light intensity of the light receiving portion 51b. For example, as Figure 7 As shown in part (a) of the figure, when the toner in the accommodating chamber 8a of the developing container 8 is a small amount, the remaining toner amount is judged to be at a low level. Incidentally, the state in which the remaining toner amount is at a low level refers to a state in which, for example, at a predetermined printing rate (for example, printing rate: 5%), there remains a residual toner amount that can allow further printing of several dozen sheets to several hundred sheets. Here, the printing rate is a numeral representing a percentage, which indicates how many pixels corresponding to the imageable area on the surface of the sheet correspond to pixels on which toner is deposited. The pixels mentioned herein are voltage elements constituting the electrostatic latent image formed on the photosensitive drum 1 by laser irradiation (light irradiation). Specifically, in the image forming area (letter size) on the recording material P, the case in which a full-face black image is formed is a printing rate of 100%, and the case in which no toner image is formed on the recording material P is a printing rate of 0%. In the above description, the second remaining toner amount sensor 52 is arranged not to intersect the rotation trajectory Tr of the stirring member 7 , but similar to the above-mentioned first remaining toner amount sensor 51 , the second remaining toner amount sensor 52 may also be arranged to intersect the rotation trajectory Tr of the stirring member 7 .

[0073] In addition, the optical path Q2 of the second remaining colorant amount sensor 52 is set above the rotation trajectory Tr of the stirring member 7 so as not to intersect with the rotation trajectory Tr of the stirring member 7. In addition, the light receiving portion 52b of the second remaining colorant amount sensor 52 cannot detect the light from the light emitting portion 52a when the optical path Q2 is blocked by the toner, but detects the light from the light emitting portion 52a when the optical path Q2 is not blocked by the toner. Therefore, regardless of the rotation operation of the stirring member 7, the controller 90 determines whether the remaining colorant amount is at a full load (FULL) level based on whether the light receiving portion 52b receives light, as described below. For example, Figure 7 As shown in part (b), if the toner in the accommodating chamber 8a of the developing container 8 is large, the remaining toner amount is judged to be at a full load level. Incidentally, in the above description, the second remaining toner amount sensor 52 is arranged not to intersect with the rotation trajectory Tr of the stirring member 7, but similar to the above-mentioned first remaining toner amount sensor 51, the second remaining toner amount sensor 52 may also be arranged to intersect with the rotation trajectory Tr of the stirring member 7.

[0074] Incidentally, the remaining toner amount detection / estimation method is not limited to Figure 5 Instead of the method (method) of optical residual colorant amount detection described in , various known methods of residual colorant amount detection / estimation methods can be used. For example, two or more metal plates or conductive resin sheets extending in the longitudinal direction of the developing roller are arranged on the inner wall of the developing container 8 as a frame, and the electrostatic capacity between the two metal plates or conductive resin sheets is measured, and the residual colorant amount can be detected / estimated. Alternatively, the load sensor is arranged in a form that allows the load sensor to support the developing device 30 from below, and the CPU 91 subtracts the weight of the developing device 30 when the toner is exhausted from the weight measured by the load sensor, so that the residual colorant amount can be calculated. In addition, the first residual colorant amount sensor 51 is omitted, and the controller 90 (CPU 91) can calculate the residual colorant amount based on the detection result of the second residual colorant amount sensor 52 and the light emission state of the laser.

[0075] [Print rate detection method]

[0076] In Embodiment 1, as a method of detecting the printing rate, pixel count detection sections 96 are used as measuring means, each of which is capable of counting the number of pixels to which the scanner unit 10 emits light. The pixel count detection section 96 may be configured as follows: Figure 8The controller 90 is shown as being constituted by the controller 90, but may be provided separately from the controller 90. The pixel count refers to the count of the individual image signals forming the image dots of the formed image. The controller 90 also serves as an acquisition device for acquiring the printing rate. The controller 90 estimates the amount of toner required to obtain a specific image by development as the toner consumption x [%] of the toner used for printing each (one) sheet, based on the number of pixels to which the scanner unit 10 emits light.

[0077] Incidentally, in Embodiment 1, a printing rate detection system of pixel counting is used as the printing rate detection means, but the present invention is not limited thereto. For example, the printing rate may be detected based on the detection result of the weight of the developing container during the last toner supply timing, the detection result of the weight of the current developing container, and the number of sheets subjected to image formation during the period therebetween.

[0078] [Control system of image forming apparatus]

[0079] Figure 8 1 is a block diagram showing a control system of the image forming apparatus 100. The controller 90 as a control device of the image forming apparatus 100 includes a CPU 91 as a calculation device, a RAM 92 used as an operation area of ​​the CPU 91, and a ROM 93 for storing various programs. In addition, the controller 90 includes an I / O interface 94 as an input / output port through which the controller 90 is connected to an external device, and an A / D conversion section 95 for converting an analog signal into a digital signal.

[0080] The first remaining toner amount sensor 51, the second remaining toner amount sensor 52, the installation sensor 53, and the environment detection portion 54 are connected to the input side of the controller 90. The installation sensor 53 detects the installation of the toner pack 40 on the supply opening 32a. For example, the installation sensor 53 is provided at the supply opening 32a and is composed of a pressure-sensitive switch for outputting a detection signal by being pressed by the protrusion 42 of the toner pack 40.

[0081] In addition, the operation part 300, the image forming part 60 and the remaining colorant amount panel 400 are connected to the controller 90, and the remaining colorant amount panel is a notification device capable of notifying information about the remaining colorant amount. The operation part 300 includes a display part 301 capable of displaying various setting screens, and includes physical keys, etc. The display part 301 is composed of, for example, a liquid crystal panel. The image forming part 60 includes a motor M1, which is a driving source for driving the photosensitive drum 1, the developing roller 4, the supply roller 5, the stirring member 7, etc. By the way, it is also possible to adopt a structure in which the photosensitive drum 1, the developing roller 4, the supply roller 5 and the stirring member 7 are each driven by a separate motor.

[0082] [Remaining Toner Amount Panel]

[0083] like Fig. 9 As shown, the remaining toner amount panel 400 is provided on the right side of the front surface of the casing of the apparatus main assembly M, that is, on the side opposite to the operating portion 300 provided on the left side, and displays information on the remaining toner amount in the developing container 8. In Embodiment 1, the remaining toner amount panel 400 is a panel member composed of a plurality of (three in this embodiment) scales arranged vertically in parallel, and the respective scales correspond to the low level, the middle level, and the full level as described above.

[0084] That is to say, Fig. 9 As shown in part (a) of FIG. 1 , when only the lower scale is lit, the remaining toner amount of the developing container 8 indicates a low level as the third state. Fig. 9 As shown in part (b) of FIG. 1 , when the lower scale and the center scale are lit and the upper scale is off, the remaining toner amount of the developing container 8 indicates a medium level as the second state. Fig. 9 As shown in part (c) of FIG. 8 , all three scales are lit, and the remaining toner amount of the developing container 8 indicates a full load level as a first state. Fig. 9 The display (notification) shown in part (a) corresponds to the display (low level display or toner empty (end) display) when the remaining toner amount is the smallest among the display forms (notification forms) that the remaining toner amount panel 400 can display. Fig. 9 The display shown in part (a) of the display can inform the user that toner needs to be supplied, thereby suppressing image blanking due to toner depletion.

[0085] Incidentally, in the following description, the controller 90 determines the execution timing of the supply operation based on the residual toner amount detected by the first residual toner amount sensor 51 and the second residual toner amount sensor 52 being lower than the judgment threshold, but the present invention is not limited thereto. For example, the residual toner amount may be detected without an optical sensor, and the supply operation timing may be determined based on the parameter for determining that the residual toner amount is small being higher than the judgment threshold.

[0086] [Toner supply process]

[0087] Next, a toner supply process (supply operation) for supplying the toner in the toner pack 40 to the developing container 9 will be described. Fig.10 As shown in FIG. 1 , when the toner supply process starts, the controller 90 executes the process of step (hereinafter referred to as “S”) 1 and thereafter. In S1, the controller 90 determines whether a supply operation start instruction is provided. In Embodiment 1, the supply operation start instruction is provided by the user through the following steps: Fig.10The operation performed by the operation part 300 shown in part (b) of the display part 301. Specifically, in a state where a message prompting the user to perform the operation of button 1 is displayed at the display part 301, the user operates the operation part 300 and performs the pressing operation of button 1, thereby outputting the supply operation start instruction. Incidentally, the supply operation start instruction is not limited to the pressing operation of button 1, but the supply operation start instruction can also be output by a touch operation in the display part 301 or in response to the detection by the installation sensor 53 that the colorant pack 40 is installed on the supply opening 32a. In addition, a sensor for detecting the opening of the shutter part 41 of the colorant pack 40 is provided, and the supply operation start instruction can be output based on the detection result of the sensor. In addition, the supply operation start instruction can also be output by an operation in an external device such as a personal computer.

[0088] In S1, if the controller 90 determines that the supply operation start instruction is not provided, the controller 90 returns the process to S1, and if the controller 90 determines that the supply operation start instruction is provided, the controller 90 proceeds to S2. In S2, the controller 90 initializes the parameters of the timer T1 described later to an initial value (for example, zero) and starts the timer T1. In S3, the controller 90 drives the motor M1 to rotate the stirring member 7.

[0089] In S4 , the controller 90 executes remaining toner amount detection processing. Fig.11 It is used to show Fig.10 1. The flowchart of the remaining toner amount detection process of S4 in part (c) of FIG. 1 is shown in FIG. 1. In S41, the controller 90 causes the light emitting portions 51a and 52a of the first remaining toner amount sensor 51 and the second remaining toner amount sensor 52 to emit light. In S42, the controller 90 causes the A / D conversion portion 95 to convert the voltages V1 and V2 outputted by the light emitting portions 51a and 52a of the first remaining toner amount sensor 51 and the second remaining toner amount sensor 52, respectively, into digital signals (hereinafter referred to as A / D conversion values).

[0090] In S43, the controller 90 determines whether the A / D conversion value of the voltage V2 indicates light blocking of the optical path Q2. Here, the controller 90 determines whether the optical path Q2 is blocked by determining whether the A / D conversion value exceeds a threshold value. In S43, in the case where the controller 90 determines that the value indicates that the optical path Q2 is blocked, the controller 90 causes the process to proceed to S44. In S44, the controller 90 causes the remaining toner amount panel 400 to display that the remaining toner amount is at a full load level, and causes the process to return to S45. Fig.10 That is, Fig. 9 As shown in part (c) of FIG. 4 , all three scales of the remaining toner amount panel 400 are lit.

[0091] In S43, in the case where the controller 90 determines that the A / D conversion value of the voltage V2 does not indicate that the optical path Q2 is blocked from light, the controller 90 causes the process to proceed to S45. In S45, the controller 90 calculates the remaining amount information of the toner in the developing container 8 based on the A / D conversion value of the voltage V1. In S46, based on the remaining amount information of the toner calculated in S45, the controller 90 causes the remaining toner amount panel 400 to display that the remaining toner amount is at a low level or at a medium level, and causes the process to return to S47. Fig.10 That is, the first remaining toner amount sensor 51 and the second remaining toner amount sensor 52 output remaining amount information according to the developer amount of the developer contained in the developing container 8 during the operation of the stirring member 7.

[0092] Here, an example of residual colorant amount detection will be described. For example, the time from the start to the end of the driving of the motor M1 (the threshold value α described later) is set to 30 seconds. During these 30 seconds, the supplied colorant is flattened in the longitudinal direction in the developing container 8. When the time required for the stirring member 7 to rotate a full circle by the motor M is, for example, 1.24 seconds, the residual colorant amount detection is performed by averaging the detection results obtained by the first residual colorant amount sensor 51 and the second residual colorant amount sensor 52 during 5 rotations, that is, during this period, 1.24 seconds (each full circle) × 5 circles = 6.2 seconds are required. By the way, during the above-mentioned 30 seconds, the residual colorant amount can be detected continuously or at the timing when the colorant becomes flat. For example, the controller 90 can cause the residual colorant amount panel 400 to display based on the detection results obtained by the last 5 rotations within the above-mentioned 30 seconds. In this case, more specifically, the controller 90 causes the first remaining toner amount sensor 51 and the second remaining toner amount sensor 52 to start remaining toner amount detection 23.8 seconds after the start of the driving of the motor M, and then causes the remaining toner amount panel 400 to display the remaining toner amount level based on one detection result (corresponding to 5 rotations). Even in the result obtained based on the average value during the last 5 rotations, the accuracy is improved because the detection is performed after the toner is flattened in the longitudinal direction.

[0093] Processing returns to Fig.10 processing of part (a).

[0094] In S5, the controller 90 determines whether the timer T1 is greater than the threshold value α. The threshold value α is a preset value as described above and corresponds to the driving time of the motor M1 and the stirring member 7 in the toner supply operation. In the case where the controller 90 determines in S5 that the timer T1 is less than the threshold value α, the process returns to S4. In the case where the controller 90 determines in S5 that the timer T1 is greater than the threshold value α, the controller 90 causes the process to proceed to S6. In S6, the controller 90 stops the driving of the motor M1, so that the toner supply operation ends. For example, in the case where the threshold value α is set to 30 seconds, the time from starting to drive the motor M1 in S3 to stopping the driving of the motor M1 in S6 is 30 seconds.

[0095] In the above-mentioned toner supply process, as Fig.12 As shown in part (a), when the toner falls from the toner pack 40 into the developing container 8, the toner passes through the inclined portion 37 and enters the accommodating chamber 8a. The supply opening 32a and the inclined portion 37 are provided at one end portion in the longitudinal direction of the developing container 8, and thus the toner is supplied to the accommodating chamber 8a all together toward this end side.

[0096] Here, a case where the stirring member 7 does not rotate when the toner is supplied to the accommodation chamber 8a will be considered. In the case where the toner falls from the toner pack 40 into the developing container 8, when the stirring member 7 does not rotate in the accommodation chamber 8a for accommodating the toner, it takes time for the fallen toner to be spread over the entire area with respect to the longitudinal direction of the photosensitive drum 1. When this time becomes long, it takes time for the user who performs the toner supply operation to complete the confirmation that the toner has been supplied to the accommodation chamber 8a, so that the usability is reduced.

[0097] Therefore, in Embodiment 1, the stirring member 7 is driven for a predetermined time (threshold value α) from the time when the (toner) supply starts in the toner supply process. Fig.12 As shown in parts (b) and (c) of the drawing, the toner supplied from the toner pack 40 to one end of the developing container 8 is arranged uniformly in advance over the entire length of the accommodating chamber 8a of the developing container 8 in the longitudinal direction by the stirring member 34. Therefore, the time required for the user to confirm that the toner supply has been completed is shortened, thereby improving usability. In addition, the toner accommodated in the developing container 8 is arranged uniformly, so that the detection accuracy of the remaining amount information of the toner by the first remaining toner amount sensor 51 and the second remaining toner amount sensor 52 can be improved.

[0098] Furthermore, during the toner supply process, the remaining amount information of the toner in the developing container 8 is detected by the first remaining toner amount sensor 51 and the second remaining toner amount sensor 52 at predetermined intervals (for example, 6.2 seconds described later). Fig. 9As shown in part (a) of FIG. 1 , in a state where the remaining toner amount panel 400 shows that the remaining toner amount is at a low level, the user supplies toner from the toner pack 40 to the developing container 8. Then, the remaining toner amount panel 400 shows that the remaining toner amount is at a medium level, as shown in FIG. Fig. 9 As shown in part (b) of , and thereafter, the remaining toner amount is shown to be at a full load level, as shown in FIG. Fig. 9 As shown in part (c) of FIG. 8 , the user can reliably recognize the toner supplied from the toner pack 40 to the developing container 8, thereby improving usability.

[0099] here, Fig.12 The cross-sectional views of parts (a) to (c) show Figure 3 The 16A-16A cross section. Fig.12 In parts (a) and (b) of FIG. 1 , the arrangement of the light emitting portion 51a toward one end of the developing container 8 relative to the longitudinal direction (axial direction J1) of the photosensitive drum 21 is shown. More specifically, in FIG. Fig.12 , the light emitting portion 52a is disposed on the side opposite to the side where the supply opening 32a is disposed with respect to the axial direction J1. In addition, the light emitting portion 51a and the light receiving portions 51b and 52b are also disposed at the same / substantially the same longitudinal position of the photosensitive drum 1. Due to the limitation of the arrangement of the sensors in the main assembly M of the apparatus, there is an arrangement of the sensors as shown in FIG. Fig.12 The case shown in parts (a) and (b) of FIG. 2 . Moreover, even in such a case, by the rotation of the stirring member 7 during the toner supply, the improvement of the usability as described above can be achieved.

[0100] In addition, depending on the situation, the sensor is provided near the supply opening 32a in some cases. Fig.12 As shown in part (b) of the figure, the position of the supplied toner is biased to the left, and in some cases it takes time to even out the toner surface in the entire area relative to the longitudinal direction of the photosensitive drum 1. In order to detect an accurate toner supply state, it is necessary to even out the toner surface in the entire area relative to the longitudinal direction of the photosensitive drum 1. However, even in such a case, in Embodiment 1, by the rotation of the stirring member 7 during toner supply, the toner surface can be evened out in a short time in the entire area relative to the longitudinal direction of the photosensitive drum 1.

[0101] Hereinafter, a configuration for switching the toner supply timing according to information on the usage status of the image forming apparatus (usage status history information) will be described. In Embodiment 1, an example of changing the toner supply timing according to the printing rate and thus suppressing toner fogging due to toner deterioration is described. That is, in Embodiment 1, the information on the usage status corresponds to the printing rate. Fig.13 Specifically, the low-level display process in Embodiment 1 will be described. In S50, the image forming apparatus 100 is in the "ready" state. In S51, the controller 90 receives a print signal. In S52, the controller 90 starts an image forming operation (printing operation). The controller 90 starts the printing operation, including rotating the developing roller 4 at an appropriate timing and forming an electrostatic latent image on the photosensitive drum 1, etc. In S53, the controller 90 performs a residual toner amount detection by the first residual toner amount sensor 51 and the second residual toner amount sensor 52, and then updates the residual toner amount T [g].

[0102] In S54, the controller 90 updates the supply count "N" (N is an integer greater than or equal to 1) (when there is no history of toner supply, N = 1). Incidentally, the controller 90 controls the supply count "N" through, for example, a counter.

[0103] In S55, the controller 90 determines whether the supply count is N = 1 (that is, there is no supply history even once). When the controller 90 determines in S55 that the supply count is N = 1, the controller 90 advances the process to S56. In S56, the controller 90 updates the print rate w% starting from the installation of the image forming apparatus 100 (that is, from the initial state). In S57, the controller 90 determines whether the print rate w% updated in S56 is less than the threshold x% as a predetermined print rate. When the controller 90 determines in S57 that the print rate w% is less than the threshold x% (less than the predetermined print rate), the controller 90 advances the process to S58.

[0104] In S58, the controller 90 determines whether the residual toner amount T [g] updated in S53 is less than the amount A [g] as a second threshold (residual amount threshold). When the controller 90 determines in S58 that the residual toner amount T [g] is less than the amount A [g], the controller 90 advances the process to S59. In S59, the controller 90 determines that the residual toner amount is at a low level, and causes the residual toner amount panel 400 to give a low-level display as shown in part (a) of Fig. 9 the following.

[0105] When the controller 90 determines in S57 that the print rate w% is equal to or greater than the threshold x% (equal to or greater than the predetermined print rate), the controller 90 advances the process to S60. In S60, the controller 90 determines whether the residual toner amount T [g] is less than the amount B [g] (<A [g]) as a first threshold (residual amount threshold). When the controller 90 determines in S60 that the residual toner amount T [g] is less than the amount B [g], the controller 90 advances the process to S59. In this case, a display as shown in Fig. 9Incidentally, the amount B[g] is a value for judging a normal low-level display.

[0106] Therefore, in the case where the printing rate w% is less than the threshold value x%, when the remaining toner amount T[g] becomes less than the amount A[g] (which is greater than the amount B[g]), the controller 90 causes the remaining toner amount panel 400 to display a low level. On the other hand, in the case where the printing rate w% is above the threshold value x%, when the remaining toner amount [g] becomes less than the amount B[g] (which is less than the amount A[g]), the controller 90 causes the remaining toner amount panel 400 to give a low level display. That is, the controller 90 switches the timing of giving a low level display according to the printing rate w%, and causes the remaining toner amount panel 400 to display a low level at a timing earlier than the timing when the printing rate w% is low.

[0107] When the controller 90 determines in S55 that the supply number "N" is not N=1 (i.e., there is a supply history), the controller 90 causes the process to proceed to S61. In S61, the controller 90 updates the print rate v% based on the pixel count immediately after the last supply of the toner. Here, the term "immediately after the last supply of the toner" means, for example, in the case where the current supply number is N=2, this means immediately after the first supply of the toner is performed, and the print rate v% is a value obtained based on the pixel count from after the first supply of the toner to the current time.

[0108] In S62, the controller 90 determines whether the printing rate v% is less than the threshold value x%. If the controller 90 determines in S62 that the printing rate v% is less than the threshold value x%, the controller 90 proceeds to S58. If the controller 90 determines in S62 that the printing rate v% is greater than the threshold value x%, the controller 90 proceeds to S60.

[0109] In the case where the controller 90 determines in S58 that the remaining toner amount T[g] is the amount A[g] or more and in the case where the controller 90 determines in S60 that the remaining toner amount T[g] is the amount B[g] or more, the controller 90 returns the process to S50. In the case where the controller 90 determines in S58 that the remaining toner amount T[g] is less than the amount A[g] and in the case where the controller 90 determines in S60 that the remaining toner amount T[g] is less than the amount B[g], the controller 90 proceeds with the process to S59 and causes the remaining toner amount panel 400 to display a low level.

[0110] Therefore, even when the supply number N=2 and after the supply number N=2, when the printing rate v% is less than the threshold value x%, when the remaining toner amount T[g] becomes less than the amount A[g] (which is greater than the amount B[g]), the controller 90 causes the remaining toner amount panel 400 to display a low level. On the other hand, when the printing rate v% is above the threshold value x%, when the remaining toner amount [g] becomes less than the amount B[g] (which is less than the amount A[g]), the controller 90 causes the remaining toner amount panel 400 to give a low level display. That is, even when the supply number N=2 and after the supply number N=2, the controller 90 switches the timing of giving a low level display according to the printing rate v%, and causes the remaining toner amount panel 400 to display a low level at a timing earlier than the timing at which the printing rate v% is low.

[0111] Here, in the case of outputting a high-printing rate image, most of the toner on the developing roller 4 is consumed and replaced with the toner inside the developing container 8. On the other hand, in the case of outputting a low-printing rate image, most of the toner on the developing roller 4 is not consumed and remains on the developing roller 4 as it is, and is therefore continuously subjected to the sliding load of the developing scraper 6 and the supply roller 5. As a result, in the case of outputting a low-printing rate image, the deterioration of the toner is aggravated compared to the case of outputting a high-printing rate image. Therefore, in the case of low-printing rate printing, the amount of toner in the developing container 8 is reduced, so that the state in which the toner deteriorates the most is formed just before the new (fresh) toner is supplied.

[0112] In Embodiment 1, under a usage condition of a low printing rate where toner degradation is aggravated, new toner is supplied (replenished) in a state where the residual toner amount of the toner in the developing container 8 is large (that is, in a state before the degree of toner degradation becomes too large). Therefore, by performing control so that the degree of degradation of the toner in the developing container 8 does not exceed a certain level, toner fogging can be suppressed. Incidentally, the residual toner amount panel 400 is not limited to a liquid crystal panel, but may also be composed of a light source such as an LED or an incandescent lamp and a diffusion lens. Incidentally, in Fig. 9 In the illustrated example, the remaining toner amount panel 400 is described as a notification device, but is not limited thereto. Fig. 9 The display of part (a) may be a display indicating that toner supply is required, Fig. 9 The display of part (b) may be a display indicating that toner supply is not required, and Fig. 9 The display of part (c) may be a display indicating that the toner supply has been sufficiently performed. Incidentally, the remaining toner amount panel 400 is merely a notification device and does not restrict the operation of the device main component M. In response to this display, the user can freely select either toner supply or continued use without toner supply.

[0113] [Experiment 1]

[0114] Here, an experiment using a comparative example will be described to verify the effects of Example 1.

[0115] In the experiment, it is evaluated whether toner fogging occurs when printing an image with a 1% printing rate until the end of the service life of the main unit in an environment where the temperature is 23°C and the relative humidity is 50% RH. Conventionally, before the end of the service life of the main unit is reached, it is necessary to supply toner 5 times with a toner pack.

[0116] When the remaining toner amount of the toner in the developing container 8 becomes the smallest, toner fogging is disadvantageous. Therefore, the determination of toner fogging is performed by measuring the fogging concentration at a timing just before supplying toner from the toner pack, and the evaluation is performed according to three levels: "○" (less than 1%: no problem with image quality), "△" (1% or more and less than 5%: some influence but no problem), and "×" (5% or more: there is a problem). To measure toner fogging, a reflection densitometer ("Model TC-MOR-45", manufactured by Tokyo Denshoku Co., Ltd., using a green filter) is used, and the reflectance (%) is measured. To perform fogging measurement, a label or the like is pasted on a part of the sheet, then a pure white image is formed on the sheet, and then the sheet is output. The reflectance at the part where the label is removed from the output sheet is used as the reference reflectance, and fogging measurement is performed. The reflectance varies depending on the measurement part, and the difference between the measurement value at the part where the measurement value becomes the smallest and the measurement value (reference reflectance) at the part where the label is pasted on the sheet and then removed from the output sheet is measured as the fogging value. The smaller the numerical value of the measured fogging value, the better the image quality indicating a small amount of fogging.

[0117] In this experiment, two conditions consisting of Condition 1 and Condition 2 are set to show a low level of remaining toner amount, and in each of Condition 1 and Condition 2, the above-described evaluation of toner fogging is performed. Condition 1 is a configuration that shows a low level (shows a low level at an earlier timing) according to the amount A [g] in the remaining toner amount, and Condition 2 is a configuration that shows a low level according to the amount B [g] (<A [g]) in the remaining toner amount. The configurations and experimental results of Condition 1 and Condition 2 are shown in Table 1.

[0118] Table 1

[0119]

[0120] *1: "CD" is the condition.

[0121] *2: "EV" is the environment. "23 / 50" is 23°C / 50% RH.

[0122] *3: "LL" is the residual toner amount [g] during low-level display.

[0123] *4: "LT" is the service life of the main component.

[0124] In the case of the configuration of Condition 2, before supplying toner, the residual toner amount is reduced to B [g] (<A), so new toner is supplied in a state where the degree of deterioration of the toner in the developing container 8 is aggravated. In addition, every time the level of the residual toner amount reaches the low level, more deteriorated toner accumulates. Therefore, at the end of the service life of the main component, the toner fogging phenomenon caused by toner deterioration becomes obvious.

[0125] On the other hand, in the configuration of Condition 1, when the residual toner amount reaches an amount A [g] greater than the amount B [g] (that is, in a state before the degree of toner deterioration becomes a certain level or more), new toner is supplied. Therefore, a state with a slight degree of toner deterioration can be maintained. Compared with Condition 2, in Condition 1, the toner is supplied earlier, so six more toner supplies can be performed before the service life reaches the end of the service life of the main component compared to the conventional configuration. In Condition 1, when six toner supplies are performed, even when toner is supplied in an amount corresponding to the amount in Condition 2, good results can be obtained. Therefore, toner fogging caused by toner deterioration can be suppressed.

[0126] As described above, according to Embodiment 1, in an image forming apparatus with a toner supply method, the occurrence of image defects caused by toner deterioration can be suppressed.

[0127] Hereinafter, a configuration for switching the toner supply timing according to information on the usage status of the image forming apparatus 100 according to Embodiment 2 will be described. In Embodiment 2, the information on the usage status corresponds to the environmental temperature and humidity, specifically to the moisture content. Embodiment 2 changes the display process of the residual toner amount panel 400 in Embodiment 1. Therefore, a configuration similar to that of Embodiment 1 will be omitted from the illustration or described by labeling the same reference numerals or signs in the figure.

[0128] [Low-level display process]

[0129] Refer to Fig.14 , the low-level display process in Embodiment 2 will be specifically described. Incidentally, the processes of S61 to S64 are respectively similar to Fig.13The processes of S50 to S53 in 3 will thus be omitted from the description. In S65, the controller 90 detects the surrounding environment through the environment detection section 54 and updates the absolute water content y [g / m 3 of the surrounding environment. In S66, the controller 90 determines whether the absolute water content y [g / m 3 is less than the threshold value z [g / m 3 which is the predetermined water content. When the controller 90 determines in S66 that the absolute water content y [g / m 3 is less than the threshold value z [g / m

[0130] (less than the predetermined water content), the controller 90 advances the process to S67. Fig. 9 In S67, the controller 90 determines whether the remaining toner amount T [g] is less than the amount C (>A) [g] which is the fourth threshold value. When the controller 90 determines in S67 that the remaining toner amount T [g] is less than the amount C [g], the controller 90 advances the process to S68. In S68, the controller 90 determines that the remaining toner amount is at a low level and causes the remaining toner amount panel 400 to give a low-level display as shown in

[0131] part (a) of 3 . When the controller 90 determines in S66 that the absolute water content y [g / m 3 is above the threshold value z [g / m Fig. 9 (above the predetermined water content), the controller 90 advances the process to S69. In S69, the controller 90 determines whether the remaining toner amount is less than the amount B [g] (<A [g]) which is the first threshold value. When the controller 90 determines in S69 that the remaining toner amount T [g] is less than the amount B [g], the controller 90 advances the process to S68 and gives a low-level display as shown in

[0132] part (a) of 2 . When the controller 90 determines in S67 that the remaining toner amount T [g] is above the amount C [g] and when the controller 90 determines in S69 that the remaining toner amount T [g] is above the amount B [g], the controller 90 returns the process to S61. 3] is equal to or greater than the threshold value z%, when the remaining toner amount [g] becomes less than the amount B [g] (which is less than the amount A [g]), the controller 90 causes the remaining toner amount panel 400 to give a low level display. That is, in Embodiment 2, the controller 90 displays the remaining toner amount panel 400 according to the absolute water content y [g / m 3 ] switches the timing of giving a low level display, and makes the remaining toner amount panel 400 at a value lower than the absolute water content y[g / m 3 ]Low timing and earlier timing (i.e., earlier timing in low temperature / low humidity environment) indicate low levels.

[0133] Here, in a low temperature / low humidity environment, the charge of the charged toner is not easily removed, so that a portion of the toner carried on the developing roller 4 is excessively charged. The excessively charged toner is firmly fixed by the image force acting between itself and the developing roller 4, and its force exceeds the control force of the developing blade 6, so that improper control (that is, disorder of the toner layer on the developing roller 4) occurs. In addition, when improper control occurs, too much developer is used for development, and therefore, the amount of toner developed from the electrostatic latent image increases on the white background portion of the image.

[0134] In Embodiment 2, under the use condition of a low temperature / low humidity environment where toner fogging is unfavorable due to inappropriate control, new toner is supplied (replenished) in a state where the amount of residual toner in the developing container 8 is large (that is, in a state before the degree of toner deterioration becomes too large). Therefore, by performing control so that the degree of deterioration of the toner in the developing container 8 does not become more than a certain degree, toner fogging can be suppressed as a result. Incidentally, in Embodiment 2, C>A holds, but the relationship may also be C=A or B. <C<A。

[0135] Furthermore, Embodiment 2 may be combined with Embodiment 1. In this case, in the case of a low printing rate and a low temperature / low humidity environment, toner is supplied in a state where the remaining toner amount is maximum.

[0136] [Experiment 2]

[0137] Here, an experiment conducted using a comparative example in order to verify the effect of Example 2 will be described.

[0138] In the experiment, it was evaluated whether toner fog occurred when an image with a printing rate of 1% was printed until the end of the service life of the main assembly in an environment with a temperature of 15° C. and a relative humidity of 10% RH.

[0139] In this experiment, a low level of residual toner dose is set among three conditions consisting of Condition 3, Condition 4, and Condition 5, and in each of these Conditions 3 to 5, the above-described evaluation of toner fog is performed. Condition 3 is a configuration that shows a low level according to the amount C [g] in the residual toner dose. Condition 4 is a configuration similar to Condition 1 in Experiment 1 that shows a low level according to the amount A [g] (< C [g]) in the residual toner dose, and Condition 5 is a configuration similar to Condition 2 in Experiment 1 that shows a low level according to the amount B [g] (< A [g]) in the residual toner dose. The configurations and experimental results of Conditions 3, 4, and 5 are shown in Table 2.

[0140] Table 2

[0141]

[0142] *1: “CD” is the condition.

[0143] *2: “EV” is the environment. “23 / 50” is 23°C / 50% RH.

[0144] *3: “LL” is the residual toner dose [g] during low level display.

[0145] *4: “LT” is the service life of the main component.

[0146] In particular, in the case of the configuration of Condition 5, the increase in the mirror force due to the low temperature / low humidity environment and the increase in the deposition force due to toner deterioration are superimposed, so toner fog appears at a timing earlier than that in Experiment 1. On the other hand, in the case of Condition 3, although an increase in the mirror force due to the low temperature / low humidity environment is observed, the degree of toner deterioration can be kept from becoming more than a certain level, so toner fog can be suppressed. Incidentally, compared with Condition 3, the evaluation result becomes “Δ” in Condition 4, but does not become “×” like Condition 5. Incidentally, compared with Condition 5, toner is supplied at an earlier timing in Condition 4, so better results are obtained compared with Condition 5.

[0147] As described above, according to Embodiment 2, in the image forming apparatus with a toner supply method, the occurrence of image defects due to toner deterioration can be suppressed.

[0148] Hereinafter, a configuration for switching the toner supply timing according to information on the use status of the image forming apparatus 100 according to Embodiment 3 will be described. In Embodiment 3, the information on the use status corresponds to the number of supplies. Embodiment 3 changes the display processing of the remaining toner amount panel 400 in Embodiment 1. Therefore, configurations similar to those in Embodiment 1 will be omitted from illustration or will be described by marking the same reference numerals or symbols in the drawings.

[0149] [Low level display processing]

[0150] Reference Fig.15 , the low-level display processing in Embodiment 3 will be described in detail. Incidentally, the processing of S70 to S74 is similar to Fig.13 , and thus will be omitted from the description. In S75, the controller 90 updates the threshold value of the remaining toner amount to the Nth amount (≤ the (N+1)th amount) which is the number of supply times. For example, when the number of supply times updated in S74 is N=2nd, the controller 90 updates the threshold value of the remaining toner amount to the second amount [g]. Incidentally, the ROM 93 stores a table or the like which associates the number of supply times N and the Nth amount with each other, and the controller 90 updates the Nth amount [g] by reading information from the ROM 93.

[0151] In S76, the controller 90 determines whether the remaining toner amount T[g] is less than the Nth amount. In the case where the controller 90 determines in S76 that the remaining toner amount T[g] is less than the Nth amount [g], the controller 90 causes the process to proceed to S77. In S77, the controller 90 determines that the remaining toner amount is at a low level, and causes the remaining toner amount panel 400 to give a low level display, that is, as shown in FIG. Fig. 9 When the controller 90 determines in S76 that the remaining toner amount T[g] is greater than or equal to the "Nth amount A[g]", the controller 90 returns the process to S70.

[0152] The "Nth amount [g]" as the threshold value of the remaining colorant amount is set to satisfy "Nth amount [g] ≤ (N+1)th amount [g]". For example, the first amount [g] is A (>B), the second amount [g] becomes D (>A), the third amount [g] becomes E (>D), the fourth amount [g] becomes F (>E), ... and so on. Therefore, in Embodiment 3, the controller 90 sets the remaining colorant amount threshold value to a higher value as the number of supplies increases, thereby making the timing of displaying the low level earlier as the number of supplies increases.

[0153] Here, in the toner pack method, toner is supplied to the developer container 8 in which deteriorated toner remains, and therefore, the number of frictions becomes greater than the number of frictions in the new (fresh) state. Thus, when the toner becomes the LOW state again, the toner remaining in the developer container 8 becomes a state in which the number of frictions is greater than the number of frictions during the last LOW state, that is, in a more deteriorated state. By repeating the LOW state and the toner supply, more deteriorated toner accumulates in the developer container 8, and therefore, as a result, the degree of occurrence of fogging due to toner deterioration increases.

[0154] In Embodiment 3, in a usage condition where the number of times of supply of unfavorable toner fog increases due to inappropriate control, new toner is supplied (replenished) in a state where the amount of residual toner is large, that is, before the degree of toner deterioration becomes too large. Therefore, by performing control so that the degree of deterioration of the toner in the developing container 8 does not become more than a certain degree, toner fog can be suppressed.

[0155] [Experiment 3]

[0156] Here, an experiment conducted using a comparative example in order to verify the effect of Example 3 will be described.

[0157] In this experiment, similarly to Experiment 1, it was evaluated whether toner fog occurred when an image with a 1% print rate was printed until the end of the service life of the main assembly in an environment of a temperature of 23° C. and a relative humidity of 50% RH.

[0158] In this experiment, the remaining toner amount showing a low level was set as Condition 6, and the evaluation of toner fog was performed. Condition 6 had the following constitution.

[0159] During the first supply, a low level is shown according to the remaining toner amount A [g].

[0160] During the second supply, a low level is shown according to the remaining toner amount D[g] (>A).

[0161] During the third supply, a low level is shown according to the remaining toner amount E[g] (>D).

[0162] During the fourth supply, a low level is shown according to the remaining toner amount F[g] (>E).

[0163] During the fifth supply, the remaining toner amount G[g] (>F) shows a low level, and

[0164] At the end of the service life of the main assembly, a low level is shown in terms of the remaining toner amount H[g] (>G).

[0165] In addition, as a comparative example for comparison effects, experiments were also conducted under Condition 1 and Condition 2, and the toner fog was evaluated.

[0166] The compositions and experimental results of Condition 6, Condition 1, and Condition 2 are shown in Table 3.

[0167] Table 3

[0168]

[0169]

[0170] *1: "CD" is the condition.

[0171] *2: "EV" is the environment. "23 / 50" is 23°C / 50%RH.

[0172] *3: "LL" is the remaining toner amount [g] during the low-level display period.

[0173] *4: "TF" is the toner fog.

[0174] *5: "LT" is the service life of the main component.

[0175] In the case of the composition of Condition 2, regardless of the number of supply times, the remaining toner amount is reduced to Amount B [g] (<A). Therefore, new toner is supplied in a state where the degree of deterioration of the toner in the developing container 8 is aggravated. In addition, every time the level of the remaining toner amount reaches the low level, more deteriorated toner accumulates. Therefore, at the end of the service life of the main component, the toner fog phenomenon caused by toner deterioration becomes obvious.

[0176] In the composition of Condition 1, when the remaining toner amount reaches Amount A [g] which is greater than Amount B [g], that is, before the degree of deterioration of the toner becomes a certain level or more, new toner is supplied. And therefore, compared with Condition 2, a state with a lighter degree of toner deterioration can be maintained.

[0177] On the other hand, in the case of the composition of Condition 6 in Example 3, as the number of supply times increases, new toner is supplied while a relatively large amount of toner is retained in the developing container 8. Therefore, a state with a lighter degree of toner deterioration in the developing container 8 can be maintained.

[0178] Therefore, the toner fogging due to toner deterioration can be suppressed. In the image forming apparatus of the toner container supply method, the occurrence of fogging due to toner deterioration can be suppressed. Incidentally, in Table 3, in either of Condition 1 and Condition 6, the evaluation result at the end of the service life of the main component is "○", but more specifically, with respect to toner fogging, the evaluation result in Condition 6 is better than the evaluation result in Condition 1.

[0179] As described above, according to Embodiment 3, in the image forming apparatus of the toner supply system, the occurrence of image defects due to toner deterioration can be suppressed.

[0180] The information (historical information) about the use status of the image forming device 100 may be, for example, the toner consumption. In this case, the controller 90 causes the RAM 2 as a storage device to store the number of revolutions of the developing roller 4. Incidentally, the number of revolutions of the developing roller 4 may also be converted into a travel distance, so that the travel distance may be used. Based on the toner consumption and the number of revolutions of the developing roller 4, the controller 90 calculates a unit consumption, which is the toner consumption per revolution (one turn) of the developing roller 4 since the last supply operation (or the toner consumption per (single-pass) travel distance). The controller 90 switches the threshold to a first threshold when the unit consumption is above a predetermined consumption, and switches the threshold to a third threshold higher than the first threshold when the unit consumption is less than a predetermined consumption. Even in this case, the state in which the toner in the developing container 8 is less deteriorated can be maintained. Therefore, the toner fogging caused by toner deterioration can be suppressed. Incidentally, the number of revolutions is used when acquiring the unit consumption, but, for example, the number of revolutions of the motor M1 or the number of printed sheets may also be used.

[0181] Furthermore, as information on the use status of the image forming apparatus 100, the number of revolutions of the developing roller 4 is used, and the controller 90 may set the threshold value according to the number of revolutions of the developing roller 4. The controller 90 sets the threshold value higher as the number of revolutions of the developing roller 4 increases. That is, when the number of revolutions of the developing roller 4 at a certain point in time is Rx, and the number of revolutions of the developing roller 4 at a time after the certain point in time is Ry (>Rx), the threshold value may be set to satisfy:

[0182] (Residual amount at rotation number Rx) ≤ (Residual amount at rotation number Ry). As the rotation number of the developing roller 4 increases, the controller 90 sets the residual amount threshold value to a higher value. Even in this case, in an image forming apparatus of a toner supply method, the occurrence of image defects due to toner degradation can be suppressed.

[0183] According to the present invention, in an image forming apparatus of a toner supply system, it is possible to suppress the occurrence of image defects due to toner degradation.

[0184] While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

Claims

1. An image forming apparatus capable of performing a supply operation for supplying toner from a supply container detachably mountable to the image forming apparatus, the image forming apparatus comprising: an image bearing member configured to bear a toner image and to be rotatable; a developing member configured to supply toner to the image bearing member; a developing container configured to contain toner and provided with a supply opening through which the toner is supplied; a detecting portion configured to detect a toner amount of the toner accommodated in the developing container; a notification section configured to notify a timing at which the supply operation is performed; as well as a controller configured to perform control so that the notification portion notifies a timing of performing the supply operation when the toner amount detected by the detection portion is smaller than a threshold value, The controller performs control to set the threshold to a first threshold when a printing rate after a previous supply operation is a predetermined printing rate or more, and to set the threshold to a second threshold higher than the first threshold when the printing rate is less than the predetermined printing rate.

2. The image forming apparatus according to claim 1, further comprising: a storage portion configured to store the number of rotations of the developing member, The controller obtains a unit consumption based on a toner consumption amount which is the amount of toner consumed after a last supply operation and the number of revolutions stored in the storage portion, wherein the unit consumption is the toner consumption per number of revolutions of the developing component after the last supply operation, and the controller performs control so as to set the threshold to the first threshold when the unit consumption is above a predetermined consumption, and to set the threshold to a third threshold which is higher than the first threshold when the unit consumption is less than the predetermined consumption.

3. The image forming apparatus according to claim 1, further comprising: an environment detection section configured to detect a moisture content in an environment surrounding the image forming apparatus, The controller performs control to set the threshold to the first threshold when the water content detected by the environment detection portion is above a predetermined water content, and to set the threshold to a fourth threshold higher than the first threshold when the water content is less than the predetermined water content. 4 . The image forming apparatus according to claim 1 , wherein the controller performs control so that the threshold value is set to a higher value as the number of supply times, that is, the number of times toner is supplied to the developing container, increases.

5. The image forming apparatus according to claim 1, further comprising: a storage portion configured to store the number of rotations of the developing member, wherein the controller performs control so as to set the threshold value to a higher value as the number of rotations becomes larger.

6. An image forming apparatus capable of performing a supply operation for supplying toner from a supply container detachably mountable to the image forming apparatus, the image forming apparatus comprising: an image bearing member configured to bear a toner image and to be rotatable; a developing member configured to supply toner to the image bearing member; a developing container configured to contain toner and provided with a supply opening through which the toner is supplied; a detecting portion configured to detect a toner amount of the toner accommodated in the developing container; a notification section configured to notify a timing at which the supply operation is performed; a controller configured to perform control so as to cause the notification portion to notify a timing of performing the supply operation when the toner amount detected by the detection portion is smaller than a threshold value; as well as an environment detection section configured to detect a moisture content in an environment surrounding the image forming apparatus, The controller performs control to set the threshold to a first threshold when the water content detected by the environment detection portion is above a predetermined water content, and to set the threshold to a fourth threshold higher than the first threshold when the water content is less than the predetermined water content.

7. The image forming apparatus according to claim 6, further comprising: a storage portion configured to store the number of rotations of the developing member, The controller obtains a unit consumption based on a toner consumption amount which is the amount of toner consumed after a last supply operation and the number of revolutions stored in the storage portion, wherein the unit consumption is the toner consumption per number of revolutions of the developing component after the last supply operation, and the controller performs control so as to set the threshold to the first threshold when the unit consumption is above a predetermined consumption, and to set the threshold to a third threshold which is higher than the first threshold when the unit consumption is less than the predetermined consumption.

8. The image forming apparatus according to claim 6, wherein the controller performs control so that the threshold value is set to a higher value as the number of supply times, that is, the number of times toner is supplied to the developing container, increases.

9. The image forming apparatus according to claim 6, further comprising: a storage portion configured to store the number of rotations of the developing member, wherein the controller performs control so as to set the threshold value to a higher value as the number of rotations becomes larger.

Images