Image forming apparatus

Abstract

To provide a technique to prevent the occurrence of an adverse effect on an image caused by deterioration of toner, in an image forming apparatus of a toner container supply system.SOLUTION: An image forming apparatus comprises a developer storage chamber, a photoconductor drum on which an image is formed, and notification means that performs notification to a user by display on an indicator, and a developer supply container is removably attached to the storage chamber. The notification means performs first notification indicating that the amount of developer in the storage chamber is in a first state, second notification indicating that the amount of developer is in a second state smaller than the first state, and third notification indicating that the amount of developer is in a third state smaller than the second state. The image forming apparatus can operate in a first mode and a second mode. In the first mode, the notification means performs the notification in the order of the first notification, second notification, and third notification as the developer is consumed, and in the second mode, performs the notification in the order different from that in the first mode.SELECTED DRAWING: Figure 15

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus. [Background technology]

[0002] In general, electrophotographic image forming apparatuses form images by transferring a toner image formed on the surface of a photosensitive drum to a transfer material as a transfer medium. Known methods of replenishing developer include a process cartridge method and a toner container replenishing method. The process cartridge method is a method in which a photosensitive drum and a developer container are integrated into a process cartridge, and when the developer runs out, the process cartridge is replaced with a new one. On the other hand, the toner container replenishing method is a method in which when the toner runs out, toner is replenished from a toner container such as a toner pack or a toner bottle to the developer container.

[0003] Conventionally, a toner container refilling method has been proposed in which, when the amount of toner in a developing container falls below a predetermined remaining amount, a display is displayed to prompt the user to replenish toner, and the user can refill the toner by supplying toner from a toner pack that contains refill toner to the developing container (Patent Document 1). At this time, the predetermined remaining amount of toner in the developing container is detected by a sensor or the like, which is a detection means provided on the image forming apparatus side, and a control means (sequence) is used that determines when the predetermined amount of toner remains in the developing container based on the result. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-154302 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, when the cycle of using the toner until the amount of toner remaining in the developing container falls below a predetermined remaining amount and then replenishing the toner is repeated as in Patent Document 1, toner fogging may occur at the end of the life of the main body.

[0006] In Patent Document 1, toner is replenished to a developing container that contains deteriorated toner, so that the average number of times each toner particle in the developing container is rubbed after the toner is replenished (hereinafter, the number of rubs) is greater than that of new toner. Therefore, when the toner remaining in the developing container reaches a specified remaining amount again, the number of rubs is greater than when the toner remained in the previous specified remaining amount, and the toner remains in a deteriorated state. Repeatedly returning to the specified remaining amount and replenishing the toner causes deteriorated toner to accumulate in the developing container, which can result in worsening fogging caused by toner deterioration.

[0007] In the one-component contact development method, when the toner on the development roller passes through the development blade pressing part, the toner is rubbed, and this is the main time when the toner deteriorates. In particular, if a user continues to print many images with low print ratios, the number of prints until the toner amount reaches a specified amount increases, and the number of rubs increases accordingly, which causes the toner deterioration to progress, and for example, fogging due to toner deterioration is likely to occur.

[0008] The present invention has been made in view of the above problems, and has an object to provide a technique for suppressing image defects caused by toner deterioration in an image forming apparatus that uses a toner container for refilling. [Means for solving the problem]

[0009] The present invention employs the following configuration. A container for containing a developer; a photosensitive drum on whose surface an electrostatic latent image is formed and which receives the developer and develops the electrostatic latent image to form an image; a developing roller that supplies the developer from the developer chamber to the photosensitive drum; a notification means for notifying a user by displaying an indicator; an image forming apparatus including: a supply container for supplying the developer to the storage chamber; the notification means performs a first notification indicating that the amount of the developer in the storage chamber is in a first state, a second notification indicating that the amount of the developer in the storage chamber is in a second state in which the amount of the developer is less than that in the first state, and a third notification indicating that the amount of the developer in the storage chamber is in a third state in which the amount of the developer is less than that in the second state, the image forming apparatus is capable of operating in a first mode and a second mode different from the first mode; In the first mode, the notification means performs the first notification, the second notification, and the third notification in that order as the consumption of the developer progresses, and in the second mode, the notification means performs the notifications in an order different from that in the first mode. The image forming apparatus is characterized in that:

[0010] The present invention also employs the following configuration. A container for containing a developer; a photosensitive drum on whose surface an electrostatic latent image is formed and which receives the developer and develops the electrostatic latent image to form an image; a developing roller that supplies the developer from the developer chamber to the photosensitive drum; a notification means for notifying a user by displaying an indicator; an image forming apparatus including: a supply container for supplying the developer to the storage chamber; the notification means performs a first notification indicating that the amount of the developer in the storage chamber is in a first state, a second notification indicating that the amount of the developer in the storage chamber is in a second state in which the amount of the developer is less than that in the first state, and a third notification indicating that the amount of the developer in the storage chamber is in a third state in which the amount of the developer is less than that in the second state, the image forming apparatus is capable of operating in a first mode and a second mode different from the first mode; The notification means performs the second notification when the remaining amount of the developer becomes a first remaining amount in the first mode, and performs the second notification when the remaining amount of the developer becomes a second remaining amount that is greater than the first remaining amount in the second mode. The image forming apparatus is characterized in that: Effect of the Invention

[0011] According to the present invention, it is possible to provide a technique for suppressing image defects caused by toner deterioration in an image forming apparatus that uses a toner container for refilling toner. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a schematic view showing an image forming apparatus according to a first embodiment of the present invention; [Diagram 2] 1A and 1B are a perspective view and a front view showing a developer container and a toner pack, respectively. [Diagram 3] (a) and (b) are cross-sectional views of 40A and 40B in Fig. 2(b). [Figure 4] FIG. 1 is a perspective view showing a toner pack; [Diagram 5] 1A to 1C are front views showing an embodiment of a toner pack and first and second modified examples. [Figure 6] (a) and (b) are cross-sectional views showing the amount of toner remaining in the developing container. [Figure 7] (a) and (b) are a cross-sectional view and a circuit diagram of a toner remaining sensor. [Figure 8] Relationship between the light receiving time t of the toner remaining sensor and the amount of toner remaining T [Figure 9] Block diagram showing a control system of an image forming apparatus [Figure 10] (a)-(c) are perspective views showing the remaining toner level and the remaining toner panel. [Figure 11] Flowchart showing toner supply processing [Figure 12] Flowchart showing remaining toner amount detection process [Figure 13] FIG. [Figure 14](a)-(c) are cross-sectional views showing the supply of toner from a toner pack. [Figure 15] 1A and 1B are diagrams showing the relationship between the number of sheets P that can be printed and the amount of remaining toner T according to the first embodiment. [Figure 16] FIG. 2 is a flow chart showing a switching decision flow for each mode according to the second embodiment; [Figure 17] FIG. 10 is a diagram showing a modification of the second embodiment. [Figure 18] 13A and 13B are graphs showing the relationship between the number of sheets P and the amount of remaining toner T in the fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] A preferred embodiment of the present invention will be described in detail below with reference to the drawings. However, unless otherwise specified, the dimensions, materials, shapes, and relative positions of the components described in the embodiment are not intended to limit the scope of the present invention to those. Furthermore, the materials, shapes, and the like of the members once described in the following description are the same as those described initially, unless otherwise specified. Well-known or publicly known technologies in the relevant technical field can be applied to configurations and processes not specifically shown or described. Furthermore, duplicated descriptions may be omitted.

[0014] In addition, the recording materials used in image forming devices include various sheet materials of different materials, such as paper such as plain paper and cardboard, plastic films such as sheets for overhead projectors, sheets of special shapes such as envelopes and index paper, and cloth.

[0015] [Example 1] [Overall structure] First, a first embodiment of the present invention will be described. Fig. 1 is an overall schematic diagram of an electrophotographic monochrome laser beam printer as an image forming apparatus 100 according to the first embodiment. The paper width sizes supported by this printer are A4 and letter paper sizes. A direct transfer process unit 9 is mounted on a device body M of the image forming apparatus 100. The process unit 9 has a photosensitive drum 1, a charging roller 2 arranged around the photosensitive drum 1, a developing device 20, a static eliminator 11, and a brush member 12.

[0016] The apparatus main body M also has a scanner unit 10 that irradiates a laser onto the photosensitive drum 1 to form an electrostatic latent image. The apparatus main body M also has a transfer roller 13 that forms a transfer nip N1 between itself and the photosensitive drum 1 and transfers a toner image to a recording material P at the transfer nip N1. The transfer roller 13 comes into contact with the surface 1a of the photosensitive drum 1 and transfers the toner image on the photosensitive drum 1 to the recording material P.

[0017] In this embodiment, the process unit 9 is configured to be detachable from the apparatus main body M, but is not limited to this. For example, the process unit 9 may be configured to be non-detachable from the apparatus main body M. In addition, in the case of a full-color image forming apparatus 100, multiple process units 9 may be provided for each color (for example, four process units for yellow, magenta, cyan, and black).

[0018] The photosensitive drum 1 as an image carrier is a cylindrically shaped photosensitive member that can rotate around a rotation axis CP extending in the axial direction. The photosensitive drum 1 of this embodiment has a photosensitive layer formed of a negatively charged organic photosensitive material on a drum-shaped base body formed of aluminum. More specifically, the photosensitive drum 1 is a rigid body formed by successively applying a resistive layer, an undercoat layer, and a photosensitive layer to the outer peripheral surface of an aluminum cylinder having a diameter of 24 mm by a dip coating method, and the photosensitive layer has a charge generating layer and a charge transport layer. The charge transport layer has a film thickness of 22 μm. The photosensitive drum 1 is rotated by a drive motor around a rotation axis CP at a predetermined peripheral speed in the direction of an arrow L1. The peripheral speed of the photosensitive drum 1 determines the speed of image formation by the image forming apparatus 100, and is therefore also called the process speed.

[0019] The charging roller 2 as a charging member contacts the photosensitive drum 1 with a predetermined pressure contact force to form a charging portion N2. A charging voltage, which is a DC voltage, is applied from a charging voltage application circuit (not shown) to uniformly charge the surface 1a of the photosensitive drum 1 to a predetermined potential. In this embodiment, a charging voltage of −1400 V is applied to the charging roller 2 so that the surface potential (pre-exposure potential VD) of the photosensitive drum 1 becomes −800 V. That is, the photosensitive drum 1 is charged to the pre-exposure potential VD by the charging roller 2 in the negative polarity direction, which is the same as the polarity of the toner. The charging roller 2 has a core metal with a diameter of 6 mm, a base layer of hydrin rubber, and a surface layer of urethane, and is configured to have an outer diameter of 12 mm. The resistance of the charging roller 2 is 1×10 6 Ω or less, and the hardness is 70 degrees measured by an MD-1 rubber hardness tester. Note that, although a DC voltage is used as the charging voltage in this embodiment, the present invention is not limited to this, and may be a voltage in which an AC voltage is superimposed on a DC voltage.

[0020] The scanner unit 10 uses a polygon mirror to irradiate the photosensitive drum 1 with a laser corresponding to image data input from an external device, thereby scanning and exposing the surface 1a of the photosensitive drum 1. This exposure forms an electrostatic latent image corresponding to the image data on the surface 1a of the photosensitive drum 1. The scanner unit 10 is a semiconductor laser that irradiates a laser with a wavelength of 800 nm and can change the amount of light emitted by the laser. The scanner unit 10 is not limited to a laser scanner device, and may be, for example, an LED exposure device having an LED array in which a plurality of LEDs are arranged along the longitudinal direction of the photosensitive drum 1.

[0021] The developing device 20 has a developing container 8 which is a frame of the developing device 20, a developing roller 4, and a supply roller 5 which supplies toner to the developing roller 4. Inside the developing container 8 which serves as a storage section, a toner storage chamber 8a which stores toner (developer) and a developing chamber 8b which has the developing roller 4 are formed. The developing roller 4 and the supply roller 5 are rotatably supported by the developing container 8. The developing roller 4 is disposed at an opening of the developing container 8 so as to face the photosensitive drum 1. The supply roller 5 rotatably abuts against the developing roller 4, and scrapes off the toner remaining on the surface of the developing roller 4 which has not been developed on the photosensitive drum 1 in the developing section N3, and applies another toner stored in the developing container 8 to the surface of the developing roller 4.

[0022] Before use, the developer container 8 is filled with T0 [g] of toner, which is assumed to be enough to print 5,000 images with a print rate of 4% conforming to ISO 19752. In other words, for images with a print rate of 4% or less, it is required to print at least 5,000 images before the first toner replenishment.

[0023] The developing device 20 uses a contact development method as a developing method. That is, the toner layer carried by the developing roller 4 comes into contact with the photosensitive drum 1 at a developing portion N3 where the photosensitive drum 1 and the developing roller 4 face each other. In other words, the developing roller 4 as a developing member forms the developing portion N3 between itself and the photosensitive drum 1. A developing voltage, which is a direct current voltage, is applied to the developing roller 4 from a developing voltage application portion (not shown). Under the developing voltage, the toner carried by 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 on the surface 1a, thereby developing the electrostatic latent image into a toner image. Note that in this embodiment, a reversal development method is adopted. That is, after being charged in a charging process, the charge amount is attenuated by being exposed in an exposure process. The toner adheres to the surface area of ​​the photosensitive drum 1, forming a toner image.

[0024] In this embodiment, a toner having a particle size of 6 μm and a normal charging polarity of negative polarity is used. As an example, the toner in this embodiment is a polymerized toner produced by a polymerization method. The toner in this embodiment does not contain a magnetic component, and is a so-called non-magnetic one-component developer in which the toner is carried on the developing roller 4 mainly by intermolecular forces and electrostatic forces (image forces). However, a one-component developer containing a magnetic component may be used. In addition to toner particles, the one-component developer may contain additives (e.g., wax or silica particles) for adjusting the fluidity and charging performance of the toner. A two-component developer composed of a non-magnetic toner and a magnetic carrier may be used as the developer. When a magnetic developer is used, a cylindrical developing sleeve with a magnet arranged inside is used as the developer carrier. The developing device 20 may be a non-contact developing type in which a predetermined gap is provided between the developing device 20 and the photosensitive drum 1.

[0025] The developing roller 4 has a core metal with a diameter of 6 mm, and a surface layer of urethane rubber is applied to a base layer of silicone rubber so that the outer diameter of the developing roller 4 is 15 mm. The resistance value of the developing roller 4 is 1×10 4 ~1×10 12 The supply roller 5 is a conductive elastic sponge roller having a foam layer formed on the outer periphery of a core metal having a diameter of 6 mm. The resistance value of the supply roller 5 is 1×10 4 ~1×10 8 The hardness of the supply roller 5 can be measured by measuring the load when a flat plate having a longitudinal width of 50 mm is inserted 1 mm into the surface of the supply roller 5, and is 200 gf in this embodiment.

[0026] An agitating member 7 is provided inside the developing container 8. The agitating member 7 is driven by a drive motor to rotate, thereby agitating the toner in the developing container 8 and sending the toner toward the developing roller 4 and the supply roller 5. The agitating member 7 also circulates, within the developing container 8, the toner that has not been used in development and has been peeled off from the developing roller 4, and plays a role in making the toner in the developing container 8 uniform.

[0027] A developing blade 6 is disposed at the opening of the developing container 8 in which the developing roller 4 is disposed, and regulates the amount of toner carried by the developing roller 4. The toner supplied to the surface of the developing roller 4 is uniformly formed into a thin layer by passing the portion facing the developing blade 6 as the developing roller 4 rotates in the direction of the arrow L2, and is negatively charged by frictional charging.

[0028] The developing blade 6 is a 0.1 mm thick SUS sheet metal made of metal, and is disposed in contact with the developing roller 4 so that its free end is on the downstream side in the rotation direction of the developing roller 4. The developing blade 6 used in this embodiment is made by cutting the tip of the SUS sheet metal from the side of the surface that contacts the developing roller 4. The tip portion of the developing blade 6 is bent in the cutting direction by the cutting process.

[0029] The transfer roller 13 as a transfer section has a base layer of ion conductive sponge so that the outer diameter is 15 mm with respect to a core metal with a diameter of 6 mm. The resistance value of the transfer roller 13 is 4×10 7 The hardness is 30 degrees as measured by an Asker C rubber hardness tester manufactured by Kobunshi Keiki Co., Ltd. The width of the sponge portion of the transfer roller 13 is approximately equal to the width of a letter (8.5 inches = 215.9 mm).

[0030] When an image formation command is output to the image forming apparatus 100, an image formation process is started based on image data input from an external computer or the like connected to the image forming apparatus 100. When the image formation process is started, the photosensitive drum 1 is driven by a driving source (not shown) and rotated at a predetermined process speed in the direction of arrow L1 in Fig. 1. In this embodiment, the process speed of the photosensitive drum 1 is 140 rpm.

[0031] The process unit 9 is provided with a static eliminator 11 that eliminates static electricity from the photosensitive drum 1, downstream of the transfer nip N1 and upstream of the charging section N2 in the rotation direction (arrow L1 direction) of the photosensitive drum 1. More specifically, the static eliminator 11 as a static eliminator is disposed between the brush member 12 and the charging roller 2 in the rotation direction of the photosensitive drum 1. The static eliminator 11 eliminates the surface potential of the photosensitive drum 1 before it reaches the charging section N2 in order to generate a stable discharge at the charging section N2.

[0032] The brush member 12 is supported by a support member (not shown) and is disposed at a fixed position relative to the photosensitive drum 1, and rubs the surface of the photosensitive drum 1 as the photosensitive drum 1 rotates. The brush member 12 collects paper dust transferred from the recording material P onto the photosensitive drum 1 at the transfer nip N1, and reduces the amount of paper dust moving to the charging section N2 downstream of the brush member 12 in the moving direction of the photosensitive drum 1 and to the developing device 3. If the paper dust is not collected by the brush member 12, the paper dust will be present in the charging section N2 and hinder charging, lowering the charging potential after passing through the charging section N2 compared to the surroundings, and the part where the paper dust was attached may be unintentionally developed as black. This problem appears as black spots on a solid white image, for example. On the other hand, it is preferable to pass the brush member 12 with the transfer residual toner remaining on the photosensitive drum 1 after the transfer nip N1 still attached to the photosensitive drum 1. When toner adheres to and accumulates on the brush member 12, it remains on the brush member 12 as a toner clump, and there is a risk that the toner clump will be expelled from the brush member 12 onto the photosensitive drum 1 at an unintended time, causing a defective image. For these reasons, the ideal function of the brush member 12 is to collect as much paper dust as possible on the photosensitive drum 1, while allowing as much toner as possible to pass through.

[0033] The charging roller 2 uniformly charges the rotating photosensitive drum 1 so that the surface potential (pre-exposure potential VD) is -800 V. The scanner unit 10 irradiates a laser toward the photosensitive drum 1 based on input image data. As a result, an electrostatic latent image is formed on the uniformly charged surface 1a of the photosensitive drum 1. In this embodiment, the scanner unit 10 uses a light amount of 0.45 μJ / cm so that the post-exposure potential VL of the photosensitive drum 1 is -100 V. 2 The laser is irradiated with

[0034] 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 application unit (not shown), whereby the electrostatic latent image on the photosensitive drum 1 is developed in the developing unit N3 to form a toner image on the photosensitive drum 1. In this embodiment, a developing voltage of −400 V is applied to the developing roller 4.

[0035] In parallel with the above-mentioned image forming process, a recording material P stored in the lower part of the image forming apparatus 100 is fed. The recording material P is transported to the transfer nip N1 in accordance with the timing when the toner image formed on the photosensitive drum 1 reaches the transfer nip N1. Also, in accordance with the timing when the toner image formed on the photosensitive drum 1 reaches the transfer nip N1, a transfer voltage which is a DC voltage is applied to the transfer roller 13 from a transfer voltage application circuit (not shown). As a result, the toner image carried on the photosensitive drum 1 is transferred to the recording material P passing through the transfer nip N1. In this embodiment, a transfer voltage of +1500V is applied to the transfer roller 13.

[0036] The recording material P onto which the toner image has been transferred is transported to the fixing device 14. The fixing device 14 is of a thermal fixing type that heats and melts the toner on the recording material P to fix the image. The fixing device 14 is equipped with a fixing film 14a that includes a ceramic heater or the like for heating, and a pressure roller 14b that is in pressure contact with the fixing film 14a. When the recording material P passes between the fixing film 14a and the pressure roller 14b, the toner image is heated and pressurized. This melts the toner particles, which then become fixed, and the toner image is fixed to the recording material P. The fixing device The recording material P that has passed through the station 14 is discharged to the outside of the image forming apparatus 100 by a pair of discharge rollers (not shown).

[0037] The image forming apparatus 100 also has an environment detection unit (not shown). The environment detection unit is disposed inside the image forming apparatus 100 and detects the surrounding temperature and humidity. Based on the detection results, the biases applied to the charging roller 2 and the developing roller 4, the scanner unit 10, the transfer roller 13, the fixing device 14, and the like are corrected.

[0038] [Recovery of residual toner after transfer] The transfer residual toner remaining on the photosensitive drum 1 without being transferred to the recording material P is removed in the following process. The surface potential of the photosensitive drum 1 after the transfer process is reduced by receiving a transfer current when passing through the transfer nip N1. In this embodiment, the surface potential of the photosensitive drum 1 after the transfer process is -150V. After the transfer process, the photosensitive drum 1 is neutralized by the charge neutralizing device 11 so that the surface potential remaining on the photosensitive drum 1 becomes 0V, and the photosensitive drum 1 rotates toward the charging section N2. The transfer residual toner includes a mixture of positively charged toner and negatively charged toner that does not have sufficient charge. The charge neutralizing device 11 neutralizes the photosensitive drum 1 after transfer, and the charging roller 2 generates a uniform discharge, so that the transfer residual toner is charged negatively again. The transfer residual toner that has been negatively charged again in the charging section N2 reaches the developing section N3 as the photosensitive drum 1 rotates. Then, the surface area of ​​the photosensitive drum 1 that has passed the charging section N2 is exposed to light by the scanner unit 10 and an electrostatic latent image is written thereon, with the residual toner still adhering to the surface.

[0039] Here, the behavior of the transfer residual toner that has reached the development unit N3 will be described separately for the exposed and non-exposed parts of the photosensitive drum 1. The transfer residual toner adhering to the non-exposed part of the photosensitive drum 1 is transferred to the development roller 4 in the development unit N3 due to the potential difference between the pre-exposure potential VD of the non-exposed part of the photosensitive drum 1 and the development voltage, and is then collected in the development container 8. This is because the normal charging polarity of the toner is negative, and the development voltage applied to the development roller 4 is positive relative to the pre-exposure potential VD of the non-exposed part. The toner collected in the development container 8 is stirred and dispersed together with the toner in the development container 8 by the stirring member 7, and is carried by the development roller 4 for use again in the development process.

[0040] On the other hand, the transfer residual toner adhering to the exposed portion of the photosensitive drum 1 remains on the drum surface without being transferred from the photosensitive drum 1 to the developing roller 4 at the developing portion N3. This is because the normal charging polarity of the toner is negative, and the developing voltage applied to the developing roller 4 has a potential with a more negative polarity 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 by 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, where it is transferred to the recording material P.

[0041] In this manner, in this embodiment, the process unit 9 has a cleaner-less configuration in which the transfer residual toner is collected and reused in the developing device 20. By making the process unit 9 a cleaner-less configuration, there is no need for installation space for a collection container for collecting the transfer residual toner and the like, making it possible to further reduce the size of the image forming apparatus 100, and also reducing printing costs by reusing the transfer residual toner.

[0042] [Developer container and toner pack configuration] Next, the configurations of the developing container 8 and the toner pack 40 as a supply container will be described. Fig. 2(a) is a perspective view showing the developing container 8 and the toner pack 40, and Fig. 2(b) is a front view showing the developing container 8 and the toner pack 40. Fig. 3(a) is a cross-sectional view taken along line 40A-40A in Fig. 2(b), and Fig. 3(b) is a cross-sectional view taken along line 40B-40B in Fig. 2(b).

[0043] As shown in FIG. 2(a) to FIG. 3(b), the developing container 8 has a storage chamber 8a in which the stirring member 7 is disposed, and the storage chamber 8a as a storage section for storing the developer extends in the longitudinal direction of the developing container 8 (the left-right direction in FIG. 2(b)). The storage chamber 8a is integrally formed with a frame that rotatably supports the developing roller 4 and the supply roller 5, and stores the developer (toner) to be carried by the developing roller 4. The developing container 8 has a base 37 at one end in the longitudinal direction of the storage chamber 8a and provided with a mounting section 57. The mounting section 57, to which the toner pack 40 can be mounted, is provided at the upper end (tip) of the base 37, and a supply port 32a is formed in the mounting section 57 for supplying the developer from the toner pack 40 to the storage chamber 8a. The toner pack 40 can be mounted in the mounting section 57 in a state where it is exposed to the outside of the device.

[0044] The developing container 8 is configured so that the toner supplied from the supply port 32a reaches the stirring member 7 by its own weight alone. Here, "by its own weight alone" means that the developing container 8 is configured so that the toner reaches the stirring member 7 by its own weight, without including a rotating or swinging member (conveying member) for transporting the toner between the supply port 32a of the developing container 8 and the stirring member 7. In addition, in the developing container 8, the stirring member 7 is the rotating body closest to the supply port 32a, and is disposed so that the toner in the storage chamber 8a reaches the developing roller 4 or the supply roller 5 by rotating.

[0045] The handle 39 has a knob 39a that a user can grip by hooking his / her fingers, and the knob 39a is formed to protrude upward from the top surface of the handle 39. The base 37 is hollow inside, and a supply port 32a is formed on the top surface. The supply port 32a is configured to be connectable to a toner pack 40.

[0046] The toner pack 40 is configured to be detachably attached to the mounting portion 57 of the base 37. The toner pack 40 has a shutter member 41 provided at the opening and capable of opening and closing, and a plurality of (three in this embodiment) protrusions 42 formed corresponding to a plurality of (three in this embodiment) grooves 32b formed in the mounting portion 57. When replenishing toner to the developing container 8, the user aligns the toner pack 40 so that the protrusions 42 pass through the grooves 32b of the mounting portion 57, and connects the toner pack 40 to 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, rotating the toner pack 40 relative to the main body of the toner pack 40 and opening the shutter member 41. As a result, the toner contained in the toner pack 40 leaks out of the toner pack 40, and the leaked toner enters the hollow base 37 through the replenishing port 32a. The shutter member 41 may be provided on the supply port 32a side.

[0047] The base 37 has a slope 37a at a position facing the opening of the supply port 32a, and the slope 37a is inclined downward toward the storage chamber 8a. Therefore, the toner supplied from the supply port 32a is guided to the storage chamber 8a by the slope 37a. As shown in FIG. 3, the agitator 7 has an agitator shaft 7a extending in the longitudinal direction, and a blade portion 7b fixed to the agitator shaft 7a and extending radially outward from the agitator shaft 7a. The blade portion 7b is a flexible sheet. The agitator 7 rotates around the agitator shaft 7a.

[0048] The toner supplied from the supply port 32a located upstream in the conveying direction of the agitating member 7 is sent towards the developing roller 4 and the supply roller 5 as the agitating member 7 rotates. The conveying direction of the agitating member 7 is parallel to the longitudinal direction of the developing container 8. The supply port 32a and the base 37 are located at one end of the developing container 8 in the longitudinal direction, but repeated rotation of the agitating member 7 distributes the toner throughout the entire length of the developing container 8. In this embodiment, the agitating member 7 is composed of an agitating shaft 7a and a blade portion 7b, In order to distribute the toner over the entire length of the developing container 8, a spiral stirring shaft may be used.

[0049] In this embodiment, the supply container is configured by a toner pack 40 made of a plastic bag that is easily deformed as shown in FIG. 4 and FIG. 5(a), but is not limited thereto. For example, the toner pack may be configured by a bottle container 40B having a substantially conical shape as shown in a first modified example of FIG. 5(b), or may be configured by a paper container 40C made of paper as shown in a second modified example of FIG. 5(c). In any case, the toner pack may be of any material and shape. In addition, the method of discharging toner from the toner pack is preferably a method in which the user squeezes the toner pack 40 or the paper container 40C with the user's fingers, and in the case of the bottle container 40B, it is preferable that the user shakes the container by tapping it, etc., to cause the toner to leak out. In addition, a discharge mechanism may be provided in the bottle container 40B to discharge the toner from the bottle container 40B. Furthermore, the discharge mechanism may be configured to be engaged with the device main body M to receive a driving force.

[0050] Also, in any of the toner packs, the shutter member 41 may be omitted, or a sliding type shutter member may be applied instead of the rotating type shutter member 41. Also, the shutter member 41 may be configured to be destroyed when the toner pack is attached to the supply port 32a or when the toner pack is rotated in the attached state, or may have a removable lid structure such as a seal.

[0051] [How to detect remaining toner] Next, a method for detecting the remaining amount of toner in the developing container 8 will be described with reference to Figures 6 and 8. As shown in Figure 6, the developing container 8 of this embodiment is provided with a remaining toner amount sensor 51 (detection means) that detects remaining amount information corresponding to the remaining amount of toner in the developing container 8. Figure 6(a) is a cross-sectional view showing the developing container when the remaining amount of toner is low, and Figure 6(b) is a cross-sectional view showing the developing container when the remaining amount of toner is high.

[0052] The toner remaining amount sensor 51 has a light emitting portion 51a and a light receiving portion 51b. Fig. 7(a) is a cross-sectional view showing the toner remaining amount sensor 51, and is a schematic diagram of the toner remaining amount sensor as viewed from the direction of the arrow B in Fig. 6(a). Fig. 7(b) is a circuit diagram showing an example of the circuit configuration of the toner remaining amount sensor 51.

[0053] In FIG. 7, an LED is used for the light-emitting unit 51a, and a phototransistor that is turned on by the light from the LED is used for the light-receiving unit 52b, but this is not limited thereto. For example, a halogen lamp or a fluorescent lamp may be applied to the light-emitting unit 51a, and a photodiode or an avalanche photodiode may be applied to the light-receiving unit 51b. In FIG. 7(b), a switch (not shown) is provided between the light-emitting unit 51a and the power supply voltage Vcc, and by turning on the switch, a voltage from the power supply voltage Vcc is applied to the light-emitting unit 51a, and the light-emitting unit 51a is brought into a conductive state. On the other hand, a switch (not shown) is also provided between the light-receiving unit 51b and the power supply voltage Vcc, and by turning on the switch, the light-receiving unit 51b is brought into a conductive state by a current corresponding to the detected amount of light.

[0054] A power supply voltage Vcc and a current limiting resistor R1 are connected to the light emitting unit 51a, and the light emitting unit 51a emits light with a current determined by the current limiting resistor R1. The light emitted from the light emitting unit 51a passes through an optical path Q1 as shown in FIG. 7(a) and is received by the light receiving unit 51b. A power supply voltage Vcc is connected to the collector terminal of the light receiving unit 51b, and a detection resistor R2 is connected to the emitter terminal. The light receiving unit 51b, which is a phototransistor, receives the light emitted from the light emitting unit 51a and outputs a signal (current) according to the amount of light received. This signal is converted to a voltage V1 by the detection resistor R2 and input to an A / D conversion unit 95 of the control unit 90 (see FIG. 9(a)).

[0055] The control unit 90 (CPU 91) judges whether the light receiving unit 51b has received light from the light emitting unit 51a based on the input voltage level. The control unit 90 (CPU 91) calculates the amount of toner (amount of developer) in the developing container 8 based on the length of time that the light receiving unit 51b detects each light 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 that can output the remaining toner amount from the light receiving time and light intensity when the toner is transported by the stirring member 7, and the control unit 90 predicts / calculates the remaining toner amount based on the input to the A / D conversion unit 95 and the table.

[0056] More specifically, the optical path Q1 of the toner remaining amount sensor 51 is set so as to intersect with the rotation locus T of the agitating member 7 when viewed from the direction of the rotation axis of the agitating member 7 shown in Fig. 6. The time during which the optical path Q1 is blocked by the toner transported by the agitating member 7 during one rotation of the agitating member 7, i.e., the time during which the light receiving unit 51b does not detect the light from the light emitting unit 51a, varies depending on the amount of remaining toner. The intensity of the received light at the light receiving unit 51b also varies depending on the amount of remaining toner.

[0057] That is, when the remaining toner amount is low as shown in FIG. 6(a), the time that the light path Q1 is blocked by the toner is short, so the time that the light receiving portion 51b receives light is long, and the light receiving intensity of the light received by the light receiving portion 51b is high. On the other hand, when the remaining toner amount is high as shown in FIG. 6(b), the time that the light receiving portion 51b receives light is short, and the light receiving intensity of the light received by the light receiving portion 51b is low. Therefore, the control portion 90 can determine the remaining toner amount level based on the light receiving time or light receiving intensity of the light receiving portion 51b in this way. As an example, FIG. 8 shows the relationship between the light receiving time t [sec] and the remaining toner amount T [g]. In the "normal mode" (first mode) which is the mode used by normal users, if the remaining toner amount is detected to be B [g], the toner remaining amount status is determined to be Low, and Low is displayed on the toner remaining amount panel.

[0058] The method of detecting / estimating the remaining toner amount is not limited to the optical toner remaining amount detection method described in FIG. 6, and various well-known methods of detecting / estimating the remaining toner amount can be adopted. For example, two or more metal plates or conductive resin sheets extending in the longitudinal direction of the developing roller may be arranged on the inner wall of the developing container 8, which is a frame, and the electrostatic capacitance between the two metal plates or conductive resin sheets may be measured to detect / estimate the remaining toner amount. Alternatively, a load cell may be provided to support the developing device 30 from below, and the CPU 91 may calculate the remaining toner amount by subtracting the weight of the developing device 20 when the toner is empty from the weight measured by the load cell. In addition, although the remaining toner amount is detected by one sensor of the optical toner remaining amount detection method in this embodiment, the remaining toner amount may be detected by multiple sensors.

[0059] Although the method for detecting the remaining toner amount has been described above, the remaining toner amount can also be found by calculating the amount of toner consumption from the pixel count described below and subtracting the consumed amount. In particular, since the initial amount of remaining toner corresponds to the amount of toner filled at the time of shipment from the factory and the amount of remaining toner is clear, the method of estimating the remaining toner amount using the pixel count for the initial amount of remaining toner can be expected to be highly accurate at least until toner is replenished once.

[0060] [How to detect printing rate] In this embodiment, a measurement means (pixel count) capable of counting the number of light-emitting pixels of the scanner unit 10 is used as a method for detecting the printing rate. The printing rate detection means may be configured by the control unit 90, or may be provided separately from the control unit 90. Pixel counting refers to counting the individual image signals that form the image dots of the image to be formed. FIG. 9(b) shows an example in which the printing rate detection means is configured by the control unit 90. Each block shown in the control unit in FIG. 9(b) is configured by a program module, and performs its function according to the instructions of the program. Image data acquisition unit 9 8a acquires image data of the object to be printed. ) performs the above-mentioned pixel count. Then, the printing rate detection unit 98c detects the printing rate based on the pixel count value.

[0061] The amount of toner required to develop an image is estimated by the control unit 90 as the toner consumption x [%] used in printing on one sheet of paper from the number of pixels emitted by the scanner unit 10. Specifically, the printing rate is set to 100% when a solid black image is formed over the entire image forming area (Letter size) on the recording material P, and the printing rate is set to 0% when no toner image is formed on the recording material P.

[0062] In this embodiment, a printing rate detection system using pixel counts is used as a means for detecting the printing rate, but the invention is not limited to this. For example, the printing rate may be detected from the detection result of the weight of the developing container at the time of the previous toner supply timing, the detection result of the current weight of the developing container, and the number of sheets of paper passed between them.

[0063] [Image forming device control system] 9(a) is a block diagram showing a control system of the image forming apparatus 100. A control unit 90 as a control means of the image forming apparatus 100 has a CPU 91 as a calculation device, a RAM 92 used as a working area for the CPU 91, and a ROM 93 for storing various programs. The control unit 90 also has an I / O interface 94 as an input / output port connected to an external device, and an A / D conversion unit 95 for converting an analog signal into a digital signal.

[0064] A toner remaining amount sensor 51 and an attachment sensor 53 are connected to the input side of the control unit 90, and the attachment sensor 53 detects that the toner pack 40 is attached to the supply port 32a of the developing container 8. For example, the attachment sensor 53 is provided in the supply port 32a and is configured of a pressure-sensitive switch that outputs a detection signal when pressed by the protrusion 42 of the toner pack 40.

[0065] The control unit 90 is also connected to an operation unit 300, the image forming unit 60, and a toner remaining amount panel 400 as a notification means capable of notifying information regarding the remaining amount of toner. The operation unit 300 has a display unit 301 capable of displaying various setting screens and physical keys (buttons 302). Note that instead of physical keys, a button UI on a panel or the like may be used. The display unit 301 is, for example, configured as a liquid crystal panel. The image forming unit 60 has a motor M1 as a drive source for driving the photosensitive drum 1, the developing roller 4, the supply roller 5, the stirring member 7, and the like. Note that the photosensitive drum 1, the developing roller 4, the supply roller 5, and the stirring member 7 may be configured to be driven by separate motors, respectively.

[0066] As shown in FIG. 10, the toner remaining amount panel 400 is provided in a part of the housing of the device main body M of the image forming device 100. The toner remaining amount panel 400 displays information regarding the remaining amount of toner in the developing container 8. In this embodiment, the toner remaining amount panel 400 is a panel member including multiple (three in this case) scales 400a to 400c as indicators arranged vertically. The scale 400a corresponds to a Full level (a first state in which the remaining amount is large) regarding the remaining amount of toner. The scale 400b corresponds to a Mid level (a second state in which the remaining amount is medium). The scale 400c corresponds to a Low level (a third state in which the remaining amount is small). Figure 10(a) is an oblique view showing the toner remaining amount panel 400 (third notification) when the toner remaining amount is at a low level, Figure 10(b) is an oblique view of the toner remaining amount panel 400 (second notification) when the toner remaining amount is at a mid level, and Figure 10(c) is an oblique view of the toner remaining amount panel 400 (first notification) when the toner remaining amount is at a full level.

[0067] That is, as shown in FIG. 10(a), in normal mode, only the lower scale is lit. When the lower and center scales are lit and the upper scale is off, the toner remaining amount in the developer container 8 is at a low level. As shown in FIG. 10(b), when the lower and center scales are lit and the upper scale is off, the toner remaining amount in the developer container 8 is at a mid level. As shown in FIG. 10(c), when all three scales are lit, the toner remaining amount in the developer container 8 is at a full level. The display (notification) shown in FIG. 10(a) corresponds to the display (low level display or toner empty display) when the toner remaining amount is the lowest among the display forms (notification forms) that the toner remaining amount panel 400 can display. The display shown in FIG. 10(a) can inform the user that toner replenishment is necessary.

[0068] In addition, in the low consumption mode (second mode) which is assumed to be used by the user with less toner consumption, the scales 400a to 400c can be displayed in a different order from the normal mode (first mode). For example, as the consumption of the developer progresses, the Full level shown in FIG. 10(c) may be directly advanced to the Low level shown in FIG. 10(a) without passing through the state shown in FIG. 10(b). The remaining toner amount at the timing of switching from the Full level to the Low level in this low consumption mode is the same as the remaining toner amount at the timing of switching from the Full level to the Mid level in the normal mode. Therefore, in the low consumption mode, the Low level is displayed in a state where more toner remains than in the normal mode. That is, since the user is prompted to replenish toner earlier than in the normal mode, the ratio of newly replenished toner to the toner in the developing container 8 after replenishment (newly replenished developer ratio) becomes smaller than in the normal mode. Therefore, since the toner is replenished at an earlier timing, the progress of toner deterioration caused by repeated rubbing of the same toner can be slowed down. If the timing at which the low level display (remaining toner amount) is made in the low consumption mode is earlier than the timing at which the low level display is made in the normal mode, the effect of prompting early replenishment of toner can be obtained.

[0069] Also, other variations can be provided for the scales 400a to 400c as indicators in the low consumption mode. For example, as a variation, the initial state in the low consumption mode may be set to the Mid level shown in FIG. 10(b), and as the consumption of the developer progresses, the level may be shifted to the Low level shown in FIG. 10(c). As another variation, as the consumption of the developer progresses, the level may be shifted from the Full level shown in FIG. 10(c) to the Mid level shown in FIG. 10(b), and may not be shifted to the Low level shown in FIG. 10(c). In this case, in the low consumption mode, the user is prompted to replenish toner in the state shown in FIG. 10(b). In either case, the user is notified of the need for toner replenishment earlier in the low consumption mode than in the normal mode.

[0070] [Toner supply process] Next, a toner replenishment process when the user replenishes the toner in the toner pack 40 to the developing container 8 will be described. As shown in the flowchart of FIG. 11, when the toner replenishment process starts, the control unit 90 judges whether or not there has been an instruction to start the replenishment operation (step S1). In this embodiment, the instruction to start the replenishment operation is an operation by the user via the operation unit 300. Specifically, with a message prompting the user to operate the button 302 displayed on the display unit 301, the user operates the operation unit 300 to press the button 302, and the instruction to start the replenishment operation is output.

[0071] The instruction to start the replenishing operation is not limited to the pressing of the button 302, but may be output by a touch operation on the display unit 301 or in response to the mounting sensor 53 detecting that the toner pack 40 has been mounted in the replenishing port 32a. Also, a sensor may be provided that detects that the shutter member 41 of the toner pack 40 has been opened, and the instruction to start the replenishing operation may be output based on the detection result of this sensor. Also, the replenishing operation may be started in response to an operation input from an external device such as a PC or a workstation.

[0072] If it is determined that a replenishment operation start command has been issued (step S1: Yes), the control unit 90 initializes parameters of timers T1 and T2 (described later) to initial values ​​(e.g., zero) and starts the timers T1 and T2 (step S2). Then, the control unit 90 drives the motor M1 (step S3) to rotate the stirring member 7.

[0073] Next, the control unit 90 executes a toner remaining amount detection process (step S4). The toner remaining amount detection process will be described with reference to the flow of the subroutine in FIG. 12. First, the control unit 90 causes the light emitting unit 51a of the toner remaining amount sensor 51 to emit light (step S41). Then, the control unit 90 converts the voltage V1 output by the light receiving unit 51b of the toner remaining amount sensor 51 into a digital signal (hereinafter referred to as an A / D conversion value) by the A / D conversion unit 95 (step S42). Note that, in order to improve the calculation accuracy, it is also preferable to repeat the processes of steps S41 and S42 multiple times (for example, five times), calculate an average value, and output it as the A / D conversion value.

[0074] Next, the control unit 90 judges whether the A / D conversion value of the voltage V1 indicates that the optical path Q1 is blocked (step S43). Whether the optical path Q1 is blocked is judged based on whether the light receiving time t is below a threshold. The judgment of whether the optical path Q1 is blocked may also be based on whether the A / D conversion value exceeds a threshold. If the A / D conversion value indicates that the optical path Q1 is blocked (step S43: Yes), the control unit 90 causes the toner remaining panel 400 to display that the toner remaining amount is at the Full level (step S44). That is, as shown in FIG. 10(c), all three scales of the toner remaining panel 400 are lit.

[0075] On the other hand, if the A / D conversion value of the voltage V1 does not indicate that the optical path Q1 is blocked (step S43: No), the control unit 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 (step S45). Then, the control unit 90 causes the toner remaining amount panel 400 to display that the remaining amount of toner is at a low level or a mid level based on the calculated remaining amount information of the toner (step S46). When step S44 or step S46 is completed, the toner remaining amount detection process is terminated. That is, the toner remaining amount sensor 51 as a detection means outputs remaining amount information according to the amount of developer contained in the developing container 8 while the stirring member 7 is operating.

[0076] Returning to FIG. 11, the explanation will be continued. The control unit 90 judges whether the timer T1 is equal to or greater than the threshold value α (step S5). The threshold value α is a preset value, and corresponds to the driving time of the motor M1 and the stirring member 7 in the toner supply process. If the timer T1 is less than the threshold value α (step S5: No), the process returns to step S4 and the remaining amount detection process is executed again. If the timer T1 is equal to or greater than the threshold value α (step S5: Yes), the control unit 90 stops the driving of the motor M1 (step S6) and ends the toner supply process. For example, if the threshold value α is set to 60 seconds, it will be 60 seconds from when the motor M1 starts to drive in step S3 to when the motor M1 is stopped in step S8.

[0077] The movement of toner when toner is replenished is shown in Figures 14(a) to 14(c). The cross-sectional views of Figures 14(a) to 14(c) show the 16A-16A cross section of Figure 3. Figure 14(a) shows the state when toner pack 40 is attached to the replenishing port, Figure 14(b) shows the state when toner has started to leak from toner pack 40, and Figure 14(c) shows the state when all the toner in toner pack 40 has been replenished.

[0078] In the above-described toner supply process, when toner drops from the toner pack 40 into the developing container 8 as shown in Fig. 14(a), the toner passes through the base 37 and enters the storage chamber 8a. Since the supply port 32a and the base 37 are disposed at one end in the longitudinal direction of the developing container 8, the toner is supplied to the storage chamber 8a all at once on the one end side.

[0079] Here, consider a case where the agitator 7 is not rotating when the toner is supplied to the storage chamber 8a. When the toner is dropped from the toner pack 40 into the developing container 8, if the agitator 7 is not rotated in the storage chamber 8a that stores the toner, it takes time for the dropped toner to spread over the entire longitudinal area of ​​the photosensitive drum 1. If this time is long, it takes time for the user performing the toner supply operation to confirm that the toner has been supplied into the storage chamber 8a, which reduces usability.

[0080] Therefore, in this embodiment, the agitator 7 is driven for a predetermined time (threshold value α) from the start of toner supply in the toner supply process. As a result, as shown in Figs. 14(b) and 14(c), the toner supplied from the toner pack 40 to one end of the developer container 8 is quickly leveled over the entire length of the storage chamber 8a of the developer container 8 in the longitudinal direction by the agitator 7. This shortens the time it takes for the user to confirm that toner supply has been completed, thereby improving usability. In addition, since the toner contained in the developer container 8 is leveled, the accuracy of detection of remaining toner information by the toner remaining amount sensor 51 can be improved.

[0081] During the toner replenishment process, the toner remaining amount sensor 51 detects the remaining amount of toner in the developing container 8 at predetermined time intervals. For example, as shown in Fig. 10(a), when the toner remaining amount panel 400 indicates that the remaining amount of toner is at a low level, the user replenishes toner from the toner pack 40 to the developing container 8.

[0082] Then, the toner remaining amount panel 400 displays that the toner remaining amount is at the Mid level as shown in Fig. 10(b), and then displays that the toner remaining amount is at the Full level as shown in Fig. 10(c). This allows the user to reliably recognize that toner has been replenished from the toner pack 40 to the developing container 8, thereby improving usability.

[0083] In some cases, the sensor may be disposed immediately below the supply port 32a. In such a case, as shown in FIG. 14(b), the supplied toner may be biased to the left side, and it may take time for the toner surface to be leveled over the entire longitudinal area of ​​the photosensitive drum 1. In order to accurately detect the toner supply state, the toner surface needs to be leveled over the entire longitudinal area of ​​the photosensitive drum 1. However, even in such a case, in this embodiment, the rotation of the stirring member 7 during toner supply allows the toner surface to be leveled over the entire longitudinal area of ​​the photosensitive drum 1 in a short time, improving usability.

[0084] [Example 2] In this embodiment, in addition to the normal mode, the image forming apparatus 100 is also provided with a low-consumption mode, which is intended for users to use the apparatus in a manner that consumes less toner. In both the normal mode and the low-consumption mode, notifications are given in the order of the Full level display in FIG. 10(c), the Mid level display in FIG. 10(b), and the Low level display in FIG. 10(c). In the low-consumption mode, a Low state is displayed to prompt the user to replenish toner when the remaining toner amount is A[g], which is greater than that in the normal mode. On the other hand, in the normal mode, when the remaining toner amount reaches B[g], the display on the toner remaining amount panel 400 is switched to Low to prompt the user to replenish toner. Here, A>B. That is, if the remaining toner amount displayed at the Low level in the normal mode is the first remaining amount, and the remaining toner amount displayed at the Low level in the low-consumption mode is the second remaining amount, the second remaining amount is greater than the first remaining amount. Therefore, in the low-consumption mode, the user is prompted to replenish toner when there is more toner remaining than in the normal mode.

[0085] Figure 15(a) and Figure 15(b) show the normal and low power consumption modes, respectively. The graph shows the relationship between the number of prints P [sheets] and the remaining toner amount T [g]. The downward black triangles (Pn, Pw) indicate the timing for toner replenishment. A new developer container 8 contains T0 [g] of toner, and as more prints are made, the remaining toner amount gradually decreases.

[0086] In normal mode, when remaining toner reaches B [g], the display on toner remaining panel 400 switches to Low to prompt the user to replenish toner. When toner is replenished, the remaining toner increases again to T0 [g], then decreases again, and consumption and replenishment are repeated. On the other hand, in low consumption compatible mode, when remaining toner reaches A [g], the display on toner remaining panel 400 switches to Low to prompt the user to replenish toner. When toner is replenished, the remaining toner exceeds T0 [g], and consumption and replenishment are repeated from there.

[0087] As shown in Table 1, the relationship between the remaining toner amount and the toner remaining amount panel 400 changes in each mode. The user can select whether to use the low consumption mode or the normal mode immediately after installing the printer from the operation panel shown in Figure 13 or the printer setting screen on a personal computer connected to the printer.

[0088] Table 1 shows the relationship between the remaining toner amount T and the remaining toner amount panel in each mode (A>B in the table). [Table 1]

[0089] Usage that consumes less toner here means that toner consumption is low relative to the number of prints or the number of rotations of the developing roller 4. For example, a user who prints a lot on small-sized paper such as A5 size tends to consume less toner per page than a user who uses regular A4 paper, since the printing area of ​​the paper is smaller. Also, even among users of A4 paper, users who continue to print images with extremely low printing rates (such as the answer section of a test or questionnaire) are also considered to be users who consume less toner.

[0090] <Evaluation method> In this embodiment, durability tests were conducted in two modes, normal mode and low consumption mode, and the number of sheets on which image fog occurred due to toner deterioration was evaluated. In normal mode, durability tests were conducted on images on A4 paper with a print rate of 2.5%. Toner was replenished when the remaining toner was determined to be low, and durability was continued until the printer reached the specified life of the main unit, which was 50,000 (50k) sheets, and the occurrence of fog was confirmed.

[0091] In the low consumption mode, the durability test was conducted on an image with a print rate of 2.5% on A5 paper. The print rate converted to A4 paper is 1.25%. In this embodiment, the print rate converted to the standard A4 size is defined as the print rate. Since the paper size is half that of A4 paper, the toner consumption is half at the same print rate. Toner was replenished when the remaining toner was judged to be low, and the durability test was continued until the printer reached the specified life of 50,000 sheets, and the occurrence of fogging was confirmed. The evaluation environment was a temperature of 15°C and humidity of 10%.

[0092] To measure the fog, a reflection densitometer (Model TC-MOR-45, Tokyo Denshoku Co., Ltd.) was used. The reflectance (%) was measured using a green filter manufactured by Epson Corporation. The criteria for judging toner fog were as follows: if fog with a reflectance of 5% or more occurred on the paper during durability, it was judged as × (fog present), and otherwise it was judged as ○ (fog absent). When measuring fog, Post-it (registered trademark) or the like was attached to a part of the paper to be printed, a plain image was formed, and the paper was output. Then, the reflectance of the part of the output paper from which the attached Post-it was removed was used as the reference reflectance of the paper itself, and fog measurement was performed. Since the reflectance differs depending on the measurement part, measurements were performed on a sufficient number of multiple parts, and the difference between the measured value of the part with the smallest value and the measured value (reference reflectance) of the part to which the Post-it was attached was calculated as the fog value. The smaller the measured fog value, the less the fog amount, and the better the image quality.

[0093] The results are shown in Table 2. In this embodiment, both the A4 paper durability test in the normal durability mode and the A5 paper durability test in the low consumption mode reached the lifespan of the main unit of 50,000 sheets without fog with a reflectance of 5% or more. In addition, the number of prints until the first toner supply notification was 6,500 sheets for both the A4 paper durability test and the A5 paper durability test, which exceeds the expected number of prints of 5,000 sheets.

[0094] Table 2 shows the durability evaluation results for the examples and comparative examples. [Table 2]

[0095] [Comparative Example 1] In this comparative example, both the A4 paper durability test and the A5 paper durability test were performed in normal mode. All other conditions were the same as in Example 1. The results are added to Table 2.

[0096] In this comparative example, the A4 paper durability test reached the end of the printer's lifespan without fog occurring, but the A5 paper durability test showed fog with a reflectance of 5% or more at 12,000 sheets before the first toner replenishment. At this point, the durability test was terminated.

[0097] [Comparative Example 2] In this comparative example, both the A4 paper durability test and the A5 paper durability test were performed in low consumption mode. The results are added to Table 2. In both tests, the printer reached its lifespan of 50,000 sheets without generating fog with a reflectance of 5% or more. However, in the normal durability test with A4 paper, the number of prints until the first toner supply notification was 3,500 sheets, which was less than the expected number of prints of 5,000 sheets.

[0098] The above results will be considered. Let us consider the friction and deterioration of toner in the developing device 20. The toner on the developing roller 4 that has been rubbed by the developing blade 6 and not developed in the developing section N3 is once scraped off by the supply roller 5 and collected in the developing container 8. Meanwhile, toner is supplied onto the developing roller 4 by the supply roller 5 in exchange for it, and the toner is coated onto the developing roller 4 while being rubbed and charged by the developing blade 6.

[0099] In the case of A4 paper durability, the toner consumption per sheet is greater than that in the case of A5 paper durability, and the rate at which the toner that has been rubbed once by the developing blade 6 is developed on the photosensitive drum 1 and goes out of the developing device 20 is greater than that in the case of A5 paper durability. On the other hand, in the case of A5 paper durability, the toner consumption per sheet is smaller, so most of the toner that has been rubbed on the developing roller 4 is not consumed. Although it is peeled off from the developing roller 4 by the supply roller 5, it remains in the developing container 8. As the durability progresses, the toner that has been rubbed once is again supplied to the developing roller 4 by the supply roller 5, rubbed by the developing blade 6, and peeled off by the recovery roller... and this operation is repeated. As a result, compared to the normal durability of A4, toner deterioration progresses more quickly relative to the number of prints. In particular, the toner in the developing container 8 decreases, and the toner is in the most deteriorated state just before new toner is replenished, and the risk of fogging increases. Conversely, if the amount of toner in the developing container 8 is large, the probability that the toner that has been rubbed once will be coated on the developing roller 4 again and rubbed will decrease, which is advantageous in terms of delaying the progression of deterioration.

[0100] The toner deterioration referred to here refers to a state in which the toner loses its fluidity and charging performance and its adhesive force to various components increases due to the toner becoming deformed due to friction load or external additives becoming embedded in the toner matrix and losing their functions. As the toner deterioration progresses, the toner's charge amount decreases (or the charging polarity is reversed), weakening the ability to control the toner by the electric field. Furthermore, as the toner deterioration progresses, the toner's adhesive force to the photosensitive drum 1 increases, so the toner adheres to areas on the photosensitive drum where no latent image is drawn, making it easier for fogging to occur. Furthermore, toner with increased adhesive force also adheres to the charging roller 2, lowering the charging performance of the charging roller 2 and lowering the potential on the surface of the photosensitive drum 1, making fogging easier to occur on this surface as well.

[0101] In the second embodiment, the durability test was performed in the low consumption mode for A5 paper, which is prone to toner deterioration, so new toner is replenished when the remaining toner amount in the developing container 8 is large, that is, before the degree of toner deterioration becomes too large. In this way, by controlling the degree of toner deterioration in the developing container 8 so that it does not exceed a certain level, toner fogging can be suppressed. In addition, since the overall amount of toner is large after toner replenishment, the probability that the same toner is subjected to a continuous friction load on the developing roller 4 is reduced, and the progression of toner deterioration is gradual. In addition, since the amount of toner consumed is small, the number of prints until the first replenishment can be secured.

[0102] On the other hand, in the first embodiment, in the A4 paper durability test in which toner consumption is high, even with the remaining toner amount B [g] in the normal mode, toner deterioration is within the allowable range and the number of prints until the first replenishment can be secured.

[0103] In the A5 paper durability test in Comparative Example 1, the test was performed in normal mode, which increased the number of times the toner was rubbed, causing toner deterioration to progress, and fog due to toner deterioration occurred before the remaining toner amount reached B [g] (before the first replenishment).

[0104] In Comparative Example 2, both durability tests were performed in low consumption mode, so there was no fogging due to toner deterioration. However, because toner was replenished when the remaining toner amount was A [g], which was higher than in the normal mode, the number of sheets before the first toner replenishment was reduced to 3,500 sheets. One solution to this problem would be to increase the toner loading amount from the beginning beyond the current T0 [g], but this would increase the overall cost of the device.

[0105] From the above results, it can be said that the embodiment is superior because it can handle both A4 and A5 endurance with a necessary and sufficient amount of toner and print the same number of sheets for both. Therefore, it can be seen that only in the embodiment 1, which has two modes, the normal mode and the low consumption mode, and uses them depending on the endurance conditions, the desired number of prints can be achieved without the occurrence of fogging due to toner deterioration. That is, in the present invention, in the mode for printing at low printing speed, the display of the toner remaining panel 400 can be changed to prompt replenishment at an appropriate timing. As a result, it is possible to slow down toner deterioration and reduce the occurrence of image defects such as toner fogging caused by toner deterioration.

[0106] [Example 3] In the above embodiment, an example was described in which the user himself selected the normal mode or the low-power mode, but in this embodiment, an example will be described in which the device automatically determines whether the normal mode or the low-power mode is more appropriate and switches the mode. Note that a description of the configuration and operation common to the first embodiment will be omitted.

[0107] In this embodiment, the operating mode is determined by the average print rate of the images printed by the user from the beginning. The print rate is calculated based on A4 paper. In other words, if the print rate on A5 paper is 2.5%, the print rate on A4 paper is 1.25%.

[0108] FIG. 16 shows a judgment flow diagram. When a print operation is started (step S81) and a predetermined number of processed sheets has passed, the control unit 90 calculates the average print rate in the prints so far (step S82). The average print rate is typically calculated by calculating the average print rate at the time when a predetermined number of sheets have been printed. In addition, when toner is replenished after a series of printing with a high print rate, and images with a low print rate are printed successively thereafter, the possibility that the average print rate is determined to be below the threshold value is low. In such a case, control may be performed to enable the setting of the low consumption mode. For example, when the average print rate up to that point exceeds a predetermined value (for example, 10%), the average print rate is always reset, and a print rate exceeding the predetermined value is not used for calculating the average print rate, but is used when the print rate becomes small.

[0109] Here, from the start of use of the device to the determination process described later, the operation mode is controlled as the normal mode. Next, the control unit 90 detects the amount of remaining toner using the toner remaining sensor 51 in the same manner as in the first embodiment, inputs the output voltage V1 to the A / D conversion unit 95, and calculates the amount of remaining toner based on the input value and the table (step S83).

[0110] Next, the control unit 90 judges whether the remaining toner amount is equal to or less than A+α[g] (step S84). Here, the state where "the remaining toner amount is A+α[g]" indicates that the current remaining toner amount is slightly more than the remaining toner amount A[g], which is the judgment criterion in the low consumption compatible mode described above. α[g] may be determined appropriately, for example, a few grams (single digit grams). If the remaining toner amount is greater than A+α[g], the mode is not changed and the flow returns to the beginning (S84: Yes).

[0111] On the other hand, if the remaining toner amount is A+α[g] or less (S84: No), the control unit 90 judges whether the average print rate at the time the user printed was 2% or less (step S85). If the average print rate is 2% or less (S85: Yes), the control unit 90 selects the low consumption compatible mode (step S86). On the other hand, if the average print rate is greater than 2% (S85: No), the normal mode continues (step S87). Once the mode has been determined, the control unit 90 determines whether the mode is selected. This will continue for the life of the unit.

[0112] In this embodiment, it is possible to automatically switch to an appropriate mode without the user having to select a mode. When a durability test was performed in the same manner as in the first embodiment, the durability test continued in the normal mode in the A4 paper durability test, but switched to the low consumption mode after 6000 sheets in the A5 paper durability test, and the remaining amount panel 400 displayed "Low" at 6500 sheets as in the first embodiment, and toner was replenished. The durability test results were the same as in the first embodiment.

[0113] In this embodiment, the mode switching decision was made based on the average printing rate from the initial state until the remaining toner amount reached A+α, but it is also possible to divide the average printing rate into sections, for example by making the decision based on the average printing rate of the last 1,000 sheets leading up to A+α.

[0114] In addition, in this embodiment, the mode once determined is controlled in the same mode until the end of the life of the main body, but it is also possible to determine again which mode to use when A+α is reached again after toner replenishment and switch modes.

[0115] (Modification) As a modified example of the mode determination method of this embodiment, a method as shown in FIG. 17 may be used. FIG. 17 is a graph with the number of prints on the horizontal axis and the amount of remaining toner on the vertical axis, showing the transition of the remaining toner during printing. In this modified example, the control unit 90 continuously monitors the relationship between the number of prints and the amount of remaining toner. If the transition of the remaining toner according to the number of prints is in an area larger than the predetermined relationship shown by Cth in the figure (for example, Ca in the figure), it is determined that the user consumes less toner, and the operation mode is set to the low consumption corresponding mode. On the other hand, if the transition of the remaining toner is in an area lower than Cth (for example, Cb in the figure), the operation mode is set to the normal mode. The determination is made when the remaining toner is (A+α) [g] or more. In FIG. 17, the number of prints is shown on the horizontal axis, but the determination may be made based on the rotation distance of the developing roller 4. Furthermore, the remaining toner may be estimated based on the value of the remaining toner sensor 51, or may be calculated from pixel counts.

[0116] Although the average print rate is used as the mode determination method in this embodiment, a method may be used which detects whether more A4 paper or more A5 paper is printed, and switches to normal mode when more A4 paper is printed, and switches to low consumption mode when more paper smaller than A4 is printed. Detection methods include using media size information specified by the user, detecting the paper size from a paper width sensor or a register sensor provided on the paper transport path, detecting from the light emission time or light emission area of ​​the scanner unit 10, and determining from the image size after image processing.

[0117] In each embodiment, if a user who used to print a lot of A5 paper starts printing a lot of A4 paper midway through the process, it is also possible to switch from the low-power mode to the normal mode midway through the process.

[0118] Furthermore, in each embodiment, two modes, the normal mode and the low-consumption mode, are switched between, but a configuration may be adopted in which three or more modes are provided and switched between depending on the print rate and the usage conditions.

[0119] In addition, in each embodiment, the remaining toner amount is detected from the value of the toner remaining sensor, but it is also possible to calculate the amount of toner consumed from the pixel count value and subtract it from the initial toner amount T0 to calculate the remaining toner amount. If the amount of toner replenished from the toner pack is constant even after toner replenishment, it is possible to calculate the remaining toner amount from the pixel count value, so control may be performed based on the calculation result.

[0120] Furthermore, A[g] in each embodiment should be set appropriately in consideration of the durability of the toner, the expected number of printable pages, the initial toner amount T0[g], etc. In this embodiment, Bm is roughly halfway between T0 and B, as shown in FIG. 15, and A[g] is set to an amount slightly less than Bm. By doing so, when images with the same print ratio are printed on A4 paper and A5 paper in normal mode and low consumption mode, the number of prints will be roughly the same. This is because the toner consumption for A5 paper is half that of A4 paper. However, A[g] when encouraging toner replenishment may be set to Bm=A.

[0121] Also, it may be possible to provide both a method in which the user manually specifies the mode as in the embodiment 1 and a method in which the device automatically determines the mode as in the embodiment 2. If the determinations made by the two methods are inconsistent, the device may confirm with the user via the operation panel and ultimately use the mode specified by the user.

[0122] The toner remaining amount panel 400 is not limited to a liquid crystal panel, and may be composed of a light source such as an LED or an incandescent lamp and a diffusion lens. In the example shown in Fig. 10, the toner remaining amount panel 400 is described as a notification means for indicating the amount of toner remaining, but is not limited to this. For example, the display in Fig. 10(a) may be a display indicating that toner replenishment is required, the display in Fig. 10(b) may be a display indicating that toner replenishment is not required, and the display in Fig. 10(c) may be a display indicating that toner replenishment has been performed sufficiently.

[0123] [Example 4] In this embodiment, an example will be described in which the remaining toner amount is different between normal mode and low-consumption mode when the Mid level is displayed (second notification). Figure 18(a) shows the normal mode, and Figure 18(b) shows the low-consumption mode, showing the relationship between the number of prints P [sheets] and the remaining toner amount T [g]. The downward black triangles (Pn, Pw) indicate the timing for toner replenishment. A new developer container 8 contains toner T0 [g], and the remaining toner amount gradually decreases as the number of prints increases.

[0124] 18B, first, when the remaining toner amount reaches A [g], the display of the remaining toner amount panel 400 is switched to Mid. In the low-consumption mode of this embodiment, the Mid level display prompts toner replenishment. Therefore, replenishment is performed at timing Pw1, and the display is switched to Full level.

[0125] Furthermore, in this embodiment, from this point on, when the remaining toner amount becomes T0 [g], the Mid level display is performed. That is, toner replenishment is prompted at every timing Pw, and when replenishment is performed, the display is switched to the Full level. With the configuration of this embodiment, early toner replenishment is prompted in the low consumption compatible mode, and image defects caused by toner deterioration can be suppressed.

[0126] (Modification) In addition, the replenishment timing may be the same as in FIG. 15B, and the notification content may be different from that in the second embodiment. For example, when the remaining toner amount reaches A [g], the display on the toner remaining amount panel 400 may be set to Mid level. In the low consumption compatible mode of this modification, the Mid level display prompts toner replenishment. Therefore, replenishment is performed at timing Pw, and the display is switched to Full level.

[0127] [Configuration 1] A container for containing a developer; a photosensitive drum on whose surface an electrostatic latent image is formed and which receives the developer and develops the electrostatic latent image to form an image; a developing roller that supplies the developer from the developer chamber to the photosensitive drum; a notification means for notifying a user by displaying an indicator; an image forming apparatus including: a supply container for supplying the developer to the storage chamber; the notification means performs a first notification indicating that the amount of the developer in the storage chamber is in a first state, a second notification indicating that the amount of the developer in the storage chamber is in a second state in which the amount of the developer is less than that in the first state, and a third notification indicating that the amount of the developer in the storage chamber is in a third state in which the amount of the developer is less than that in the second state, the image forming apparatus is capable of operating in a first mode and a second mode different from the first mode; In the first mode, the notification means performs the first notification, the second notification, and the third notification in that order as the consumption of the developer progresses, and in the second mode, the notification means performs the notifications in an order different from that in the first mode. 1. An image forming apparatus comprising: [Configuration 2] In the second mode, the notification means performs the first notification and the third notification in that order as the consumption of the developer progresses. 2. The image forming apparatus according to claim 1, [Configuration 3] The third notification is a display that prompts the user to replenish the developer. 3. The image forming apparatus according to claim 2, [Configuration 4] In the second mode, the notification unit performs the first notification and then the second notification in accordance with the progress of consumption of the developer. 2. The image forming apparatus according to claim 1, [Configuration 5] In the second mode, the notification means performs the second notification and the third notification in that order as the consumption of the developer progresses. 2. The image forming apparatus according to claim 1, [Configuration 6] 6. The image forming apparatus according to any one of configurations 1 to 5, wherein the second mode is a mode in which less developer is consumed than the first mode. [Configuration 7] The second mode is a mode in which the printing rate during image formation is lower than that of the first mode. 7. The image forming apparatus according to configuration 6, [Configuration 8] a detection unit for detecting the printing ratio based on image data for forming the image, Whether the image forming apparatus operates in the first mode or the second mode is determined based on the output of the detection means. 8. The image forming apparatus according to claim 7, [Configuration 9] The second mode is a mode in which a recording material having a smaller size than that of the first mode is used. 7. The image forming apparatus according to configuration 6, [Configuration 10] Whether the image forming apparatus operates in the first mode or the second mode is determined based on a user's instruction. 7. The image forming apparatus according to configuration 6, [Configuration 11] When the developer is replenished from the supply container to the storage chamber, the developer present in the storage chamber If the ratio of the developer newly replenished to the developer storage chamber to the total developer stored in the developer storage chamber is defined as a newly replenished developer ratio, The fresh replenishment developer ratio in the first mode is greater than the fresh replenishment developer ratio in the second mode. 11. The image forming apparatus according to any one of configurations 1 to 10. [Configuration 12] The amount of the developer replenished by the replenishment container is the same in the first mode and the second mode. 12. The image forming apparatus according to claim 11, [Configuration 13] A container for containing a developer; a photosensitive drum on whose surface an electrostatic latent image is formed and which receives the developer and develops the electrostatic latent image to form an image; a developing roller that supplies the developer from the developer chamber to the photosensitive drum; a notification means for notifying a user by displaying an indicator; an image forming apparatus including: a supply container for supplying the developer to the storage chamber; the notification means performs a first notification indicating that the amount of the developer in the storage chamber is in a first state, a second notification indicating that the amount of the developer in the storage chamber is in a second state in which the amount of the developer is less than that in the first state, and a third notification indicating that the amount of the developer in the storage chamber is in a third state in which the amount of the developer is less than that in the second state, the image forming apparatus is capable of operating in a first mode and a second mode different from the first mode; The notification means performs the second notification when the remaining amount of the developer becomes a first remaining amount in the first mode, and performs the second notification when the remaining amount of the developer becomes a second remaining amount that is greater than the first remaining amount in the second mode. 1. An image forming apparatus comprising: [Explanation of symbols]

[0128] 1: photosensitive drum, 4: developing roller, 8: developing container, 20: developing device, 40: toner pack, 400: toner remaining amount panel

Claims

1. A container for containing a developer; a photosensitive drum on whose surface an electrostatic latent image is formed and which receives the developer and develops the electrostatic latent image to form an image; a developing roller that supplies the developer from the developer chamber to the photosensitive drum; a notification means for notifying a user by displaying an indicator; an image forming apparatus including: a supply container for supplying the developer to the storage chamber; the notification means performs a first notification indicating that the amount of the developer in the storage chamber is in a first state, a second notification indicating that the amount of the developer in the storage chamber is in a second state in which the amount of the developer is less than that in the first state, and a third notification indicating that the amount of the developer in the storage chamber is in a third state in which the amount of the developer is less than that in the second state, the image forming apparatus is capable of operating in a first mode and a second mode different from the first mode; In the first mode, the notification means performs the first notification, the second notification, and the third notification in that order as the consumption of the developer progresses, and in the second mode, the notification means performs the notifications in an order different from that in the first mode.

1. An image forming apparatus comprising:

2. In the second mode, the notification means performs the first notification and the third notification in that order as the consumption of the developer progresses.

2. The image forming apparatus according to claim 1,

3. The third notification is a display that prompts the user to replenish the developer.

3. The image forming apparatus according to claim 2,

4. In the second mode, the notification means performs the first notification and then the second notification in that order as the consumption of the developer progresses.

2. The image forming apparatus according to claim 1,

5. In the second mode, the notification means performs the second notification and the third notification in that order as the consumption of the developer progresses.

2. The image forming apparatus according to claim 1,

6. 6. The image forming apparatus according to claim 1, wherein the second mode is a mode in which less developer is consumed than the first mode.

7. The second mode is a mode in which the printing rate during image formation is lower than that of the first mode.

7. The image forming apparatus according to claim 6,

8. a detection unit for detecting the printing ratio based on image data for forming the image, Whether the image forming apparatus operates in the first mode or the second mode is determined based on the output of the detection means.

8. The image forming apparatus according to claim 7,

9. The second mode is a mode in which a recording material having a smaller size than that of the first mode is used.

7. The image forming apparatus according to claim 6,

10. Whether the image forming apparatus operates in the first mode or the second mode is determined based on a user instruction.

7. The image forming apparatus according to claim 6,

11. When the developer is replenished from the replenishment container to the storage chamber, the ratio of the developer newly replenished to the storage chamber to the developer present in the storage chamber is defined as a newly replenished developer ratio. The fresh replenishment developer ratio in the first mode is greater than the fresh replenishment developer ratio in the second mode.

6. The image forming apparatus according to claim 1, wherein the image forming apparatus is a multi-color image forming apparatus.

12. The amount of the developer replenished by the replenishment container is the same in the first mode and the second mode.

12. The image forming apparatus according to claim 11.

13. A container for containing a developer; a photosensitive drum on whose surface an electrostatic latent image is formed and which receives the developer and develops the electrostatic latent image to form an image; a developing roller that supplies the developer from the developer chamber to the photosensitive drum; a notification means for notifying a user by displaying an indicator; an image forming apparatus including: a supply container for supplying the developer to the storage chamber; the notification means performs a first notification indicating that the amount of the developer in the storage chamber is in a first state, a second notification indicating that the amount of the developer in the storage chamber is in a second state in which the amount of the developer is less than that in the first state, and a third notification indicating that the amount of the developer in the storage chamber is in a third state in which the amount of the developer is less than that in the second state, the image forming apparatus is capable of operating in a first mode and a second mode different from the first mode; The notification means performs the second notification when the remaining amount of the developer becomes a first remaining amount in the first mode, and performs the second notification when the remaining amount of the developer becomes a second remaining amount that is greater than the first remaining amount in the second mode.

1. An image forming apparatus comprising:

Images