Image forming apparatus

Abstract

To accurately distinguish the class of toner containers.SOLUTION: A control unit determines if a toner container used for initial toner supply is a first toner container or a second toner container, from a comparison between a threshold and an output value immediately after the initial toner supply from one toner container to a storage unit, the toner supply being from a storage unit in a brand-new state. When the amount of toner remaining in the storage unit corresponding to an output value at predetermined timing before the initial toner supply is performed is defined as a first toner remaining amount, the amount of toner remaining in one storage unit based on the amount of toner filling the storage unit in the brand-new state and image information on images printed from the time in the brand-new state until the predetermined timing is defined as a second toner remaining amount, a condition where the first toner remaining amount is larger than the second toner remaining amount is defined as a first condition, and a condition where the first toner remaining amount is smaller than the second toner remaining amount is defined as a second condition, the control unit sets the threshold so that one toner container used for the initial toner supply is more easily determined to be the first toner container in a case where the first condition is satisfied than a case where the second condition is satisfied.SELECTED DRAWING: Figure 21

Description

Technical Field

[0001] The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus that forms an image on a recording material and an image forming system including the same.

Background Art

[0002] Generally, an electrophotographic image forming apparatus forms an image by transferring a toner image formed on the surface of a photosensitive drum to a transfer material as a transfer medium. And, as a developer replenishment method, for example, a process cartridge method and a toner container replenishment method are known. The process cartridge method integrates a photosensitive drum and a developing container as a process cartridge, and replaces the process cartridge with a new one when the developer runs out. On the other hand, the toner container replenishment method replenishes toner from a toner container such as a toner pack or a toner bottle to the developing container when the toner runs out.

[0003] Conventionally, an image forming apparatus provided with a toner remaining amount sensor for estimating the toner remaining amount in a developing container based on the light reception time when detection light irradiated from a light emitting unit and passing through the developing container is received by a light receiving unit has been proposed (see, for example, Patent Document 1). A stirring member for stirring the toner is provided in the developing container, and the shorter the toner remaining amount in the developing container, the longer the light reception time by the light receiving unit. And, information regarding the detected toner remaining amount is displayed on a toner remaining amount panel provided on the surface of the image forming apparatus. The toner remaining amount panel is a panel member composed of three graduations, and each graduation lights up or goes out according to the toner remaining amount to notify the user of the toner remaining amount.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present invention aims to accurately discriminate the types of toner containers.

Means for Solving the Problems

[0006] In order to solve the above-described problems, the present invention includes the following configuration.

[0007] (1) An image forming apparatus capable of mounting a plurality of toner containers including a first toner container containing toner of a first toner amount and a second toner container containing toner of a second toner amount larger than the first toner amount, the apparatus including a mounting portion capable of mounting one of the plurality of toner containers, a storage portion for storing toner replenished from the one toner container mounted on the mounting portion, a detection portion for outputting an output value corresponding to the remaining amount of toner stored in the storage portion, and a control portion. The control portion determines which of the first toner container and the second toner container the toner container used for the first toner replenishment is by comparing the output value immediately after the first toner replenishment from the one toner container to the storage portion (when the first toner replenishment is made from the new state of the storage portion) with a threshold value. The remaining amount of toner in the storage portion corresponding to the output value at a predetermined timing before the first toner replenishment is set as a first remaining amount of toner, and the remaining amount of toner in the storage portion corresponding to the output value at the predetermined timing from the new state to the printing of the image information of the image printed up to the predetermined timing is set as a second remaining amount of toner. When a first condition that the first remaining amount of toner is larger than the second remaining amount of toner and a second condition that the first remaining amount of toner is smaller than the second remaining amount of toner are defined, the control portion sets the threshold value so that it is more likely to be determined that the one toner container used for the first toner replenishment is the first toner container when the first condition is satisfied than when the second condition is satisfied. An image forming apparatus characterized by this.

Effects of the Invention

[0008] According to the present invention, the type of toner container can be accurately discriminated.

Brief Description of the Drawings

[0009]

Figure 1

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Mode for Carrying Out the Invention

[0010] Hereinafter, exemplary embodiments for carrying out the present invention will be described with reference to the drawings. However, the dimensions, materials, shapes, and relative arrangements of the components described in the following embodiments should be appropriately changed according to the configuration of the apparatus to which the invention is applied and various conditions, and the scope of the present invention is not intended to be limited to the following embodiments.

Example

[0011] FIG. 1 is a perspective view of the image forming apparatus 1 of the present embodiment. FIG. 2 is a schematic cross-sectional view of the image forming apparatus 1. The image forming apparatus 1 is a monochrome printer that forms an image on a recording material based on image information input from an external device. The recording material includes various sheet materials of different materials such as paper such as plain paper and thick paper, plastic films such as overhead projector sheets, special-shaped sheets such as envelopes and index papers, and cloth.

[0012] In the following description, when the image forming apparatus 1 is installed on a horizontal surface, the height direction (the direction opposite to the vertical direction) of the image forming apparatus 1 is defined as the Z direction. A direction that intersects the Z direction and is parallel to the rotation axis direction (main scanning direction) of the photosensitive drum 11, which will be described later, is defined as the X direction. A direction that intersects the X direction and the Z direction is defined as the Y direction. The X direction, the Y direction, and the Z direction preferably intersect perpendicularly to each other. For convenience, the plus side in the X direction is referred to as the right side, the minus side is referred to as the left side, the plus side in the Y direction is referred to as the front side or the front face side, the minus side is referred to as the rear side or the back face side, and the plus side in the Z direction is referred to as the upper side, and the minus side is referred to as the lower side.

[0013] [Overall Configuration] The overall configuration of the image forming apparatus 1 will be described with reference to FIGS. 1 and 2. Note that the image forming apparatus 1 and a supply pack 210 (see FIG. 10) described later constitute an image forming system 1000. As shown in FIG. 2, the image forming apparatus 1 includes an image forming unit 20 that forms a toner image on a recording material, a feeding unit 30 that feeds the recording material P, a fixing unit 9 that fixes the toner image formed by the image forming unit 20 onto the recording material, and a pair of discharge rollers 10.

[0014] The image forming unit 20 includes a scanner unit 50, an electrophotographic process unit 40, and a transfer roller 7 that transfers the toner image formed on the photosensitive drum 11 of the process unit 40 onto the recording material P. The process unit 40 includes a photosensitive drum 11, a cleaning unit 13 disposed around the photosensitive drum 11, a charging roller 17, a developing roller 12, and a storage unit 18 that stores toner. Note that the process unit 40 may be screwed to the housing 72 of the image forming apparatus 1 and also includes those that can be removed by a service technician.

[0015] The photosensitive drum 11 as an image carrier is a cylindrical photoconductor. The photosensitive drum 11 of the present embodiment has a photosensitive layer formed of a negatively chargeable organic photoconductor on a drum-shaped substrate formed of aluminum. The photosensitive drum 11 is rotationally driven by a motor in a predetermined direction (direction R in the figure) at a predetermined process speed.

[0016] The charging roller 17 contacts the photosensitive drum 11 with a predetermined pressure contact force to form a charging portion. Further, by applying a desired charging voltage by a charging high-voltage power supply, the surface of the photosensitive drum 11 is uniformly charged to a predetermined potential. In this embodiment, the photosensitive drum 11 is charged negatively by the charging roller 17.

[0017] The scanner unit 50 scans and exposes the surface of the photosensitive drum 11 by irradiating the photosensitive drum 11 with laser light corresponding to the image information input from an external device using a rotating polygon mirror. By this exposure, an electrostatic latent image corresponding to the image information is formed on the surface of the photosensitive drum 11. Note that the scanner unit 50 is not limited to a laser scanner device, and 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 11 may be employed.

[0018] The developing roller 12 is rotatably supported by the accommodating portion 18. Further, the developing roller 12 is disposed at the opening of the developing container 230 (see FIG. 5) including the accommodating portion 18 so as to face the photosensitive drum 11. Note that the accommodating portion 18 may be provided with a supply roller that applies toner as a developer accommodated in the accommodating portion 18 to the surface of the developing roller 12.

[0019] The process unit 40 of this embodiment uses a contact development method as a development method. That is, the toner layer carried on the developing roller 12 contacts the photosensitive drum 11 in a developing portion (developing region) where the photosensitive drum 11 and the developing roller 12 face each other. A developing voltage is applied to the developing roller 12 by a developing high-voltage power supply. Under the developing voltage, the toner carried on the developing roller 12 is transferred from the developing roller 12 to the drum surface according to the potential distribution on the surface of the photosensitive drum 11, so that the electrostatic latent image is developed into a toner image.

[0020] Further, the toner of 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 12 mainly by intermolecular forces and electrostatic forces (image forces). However, a one-component developer containing a magnetic component may also be used. In addition, the one-component developer may contain additives (for example, wax and silica fine particles) for adjusting the fluidity and charging performance of the toner in addition to toner particles. Further, 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, as the developer carrier, for example, a cylindrical developing sleeve with a magnet disposed inside is used.

[0021] The fixing unit 9 is of a heat fixing type that performs an image fixing process by heating and melting the toner on the recording material. The fixing unit 9 includes a heating roller 9a having a built-in fixing heater and a pressure roller 9b that is pressed against the heating roller 9a.

[0022] The feeding unit 30 has a cassette 4 on which the recording material P is loaded, a pickup roller 3 as a conveying unit, a feeding roller 5a, and a separating roller 5b. A front cover 70 is provided on a part of the front end surface of the image forming apparatus 1, and the front cover 70 covers the circuit board 100. The housing 72 has the front cover 70, a discharge tray 14, and an exterior cover 71 that constitutes the exterior of the image forming apparatus 1 other than the front cover 70 and the discharge tray 14. An outlet 15 through which the sheet discharged to the discharge tray 14 passes is formed in the housing 72.

[0023] As shown in FIG. 2, the image forming apparatus 1 has a circuit board 100. The circuit board 100 is composed of a wiring board 101 made of an insulator and electronic components 111, 121 soldered to the wiring board 101. Since conductor wirings are provided on the surface and inside of the wiring board 101, the electronic components 111, 121 are electrically connected. The circuit board 100 has a function of converting an alternating current supplied from the outside of the image forming apparatus 1 into a direct current or converting an input voltage to obtain a predetermined voltage value required for the image forming process.

[0024] The circuit board 100 is arranged such that the surface of the wiring board 101 on which the electronic components 111 and 121 are mounted intersects the discharge direction. Further, the wiring board 101 is provided between the front cover 70 and the scanner unit 50 in the discharge direction. The electronic components 111 and 121 are provided on the surface of the wiring board 101 facing the scanner unit 50.

[0025] [Image forming mode] The image forming mode of the image forming apparatus 1 will be described. The image forming mode of the present embodiment is a mode of forming an image on a recording material with the discharge tray 14 in the closed position, as shown in FIGS. 1 and 3(a). When a command for image formation is input to the image forming apparatus 1, an image forming process by the image forming unit 20 is started based on the image information input from an external computer connected to the image forming apparatus 1. The scanner unit 50 irradiates the photosensitive drum 11 with laser light based on the input image information. At this time, the photosensitive drum 11 is pre-charged by the charging roller 17, and an electrostatic latent image is formed on the photosensitive drum 11 by the irradiation of the laser light. Then, this electrostatic latent image is developed by the developing roller 12, and a toner image is formed on the photosensitive drum 11.

[0026] In parallel with the above-described image forming process, the pickup roller 3 of the feeding unit 30 feeds out the recording material P supported by the cassette 4. The recording material P is separated one by one by the feeding roller 5a and the separating roller 5b and conveyed to the conveying roller pair 5c. Then, the recording material P is conveyed by the conveying roller pair 5c toward the transfer nip portion formed by the transfer roller 7 and the photosensitive drum 11.

[0027] A transfer voltage is applied to the transfer roller 7 from a transfer high-voltage power source, and the toner image carried on the photosensitive drum 11 is transferred to the recording material P conveyed by the conveying roller pair 5c. The recording material P onto which the toner image has been transferred is conveyed to the fixing unit 9, and the toner image is heated and pressed when passing through the nip portion between the heating roller 9a and the pressure roller 9b of the fixing unit 9. Thereby, the toner particles are melted and then fixed, so that the toner image is fixed on the recording material P. The recording material P that has passed through the fixing unit 9 is discharged to the outside (outside the machine) of the image forming apparatus 1 from the discharge port 15 by the discharge roller pair 10 and stacked on the discharge tray 14.

[0028] When forming images on both sides of the recording material P, the discharge roller pair 10 guides the recording material P to the duplex conveyance path 16 by switching back the recording material P on which the image has been formed on the first side. The recording material P guided to the duplex conveyance path 16 is conveyed again toward the transfer roller 7 by the duplex conveyance roller pair 5d. After the image is formed on the second side of the recording material P by the transfer roller 7, the recording material P is discharged to the outside of the machine by the discharge roller pair 10. Also, after the toner image is transferred to the recording material P, the toner remaining on the photosensitive drum 11 is cleaned by the cleaning unit 13.

[0029] [Supply Unit] Next, the supply unit 200 (mounting unit) will be described with reference to FIGS. 3(a) to 7(c). As shown in FIG. 3(a), the discharge tray 14 is supported so as to be openable and closable between a closed position where the recording material P can be stacked and the image forming mode can be executed, and an open position where the discharge tray 14 is opened as shown in FIG. 3(b). An open / close detection unit (not shown) can detect whether the discharge tray 14 is in the open position or the closed position. The discharge tray 14 covers the supply unit 200 in the closed position. When the discharge tray 14 is moved to the open position, the top surface portion 240 and the supply unit 200 disposed adjacent to the top surface portion 240 are exposed. The supply unit 200 is configured such that a supply pack 210 as a toner container described later can be detachably (attachably) mounted. The image forming apparatus 1 is configured such that a user or a service technician can supply toner to the image forming apparatus 1 from the outside without removing the developing container 230 from the housing 72 (see FIG. 1).

[0030] FIG. 4 is a cross-sectional view of the developing container 230 of the image forming apparatus 1. FIG. 5 is a view of the image forming apparatus 1 with the exterior cover 71 removed, seen from above. FIG. 6 is a perspective view of the developing container 230. In FIG. 6, the lever 201 of the supply unit 200 and some members associated therewith are omitted.

[0031] As shown in FIGS. 4 to 6, the developing container 230 includes a housing portion 18 and a supply unit 200. The supply unit 200 has a lever 201, a cylindrical passage member 202, and a main body shutter 206 (see FIG. 7(b)). The passage member 202 has an extending portion 202b that extends to the housing portion 18 and a side opening 202a that connects to the extending portion 202b. The toner discharged from the supply pack 210 mounted on the supply unit 200 is supplied to the housing portion 18 through the main body shutter opening 206a of the main body shutter 206, the side opening 202a of the passage member 202, and the extending portion 202b.

[0032] The extension part 202b is connected to one end side of the accommodating part 18 in the longitudinal direction of the developing container 230, that is, in the X direction. Inside the accommodating part 18, as shown in FIG. 4, a stirring member 60 that rotates around a rotating shaft 60a extending in the X direction is provided. The stirring member 60 has blade parts 60b fixed to the rotating shaft 60a, and by being driven by a motor 311 (see FIG. 15) to rotate, it stirs and levels the toner in the accommodating part 18 replenished from the replenishment pack 210, and conveys the toner toward the developing roller 12. In this embodiment, the stirring member 60 is composed of the rotating shaft 60a and the blade parts 60b, but a spiral-shaped stirring member may be used as a configuration that allows the toner to spread throughout the entire length of the accommodating part 18.

[0033] The stirring member 60 has the role of circulating the toner peeled off from the developing roller 12 that is not used for development within the accommodating part 18 and equalizing the toner in the accommodating part 18. Note that the stirring member 60 is not limited to a rotating form. For example, a stirring member in a rocking form may be adopted. In addition to the stirring member 60, another stirring member may be provided inside the accommodating part 18.

[0034] Also, on a side surface 18a of the accommodating part 18 on the side opposite to the developing roller 12, a remaining amount detection part 312 (toner remaining amount detection part) for detecting the amount of toner in the accommodating part 18 is provided, and the remaining amount detection part 312 has a light emitting part 312a and a light receiving part 312b. The light emitting part 312a and the light receiving part 312b are arranged side by side in the X direction. The light emitted from the light emitting part 312a passes through the inside of the accommodating part 18 and is received by the light receiving part 312b. That is, the light emitting part 312a and the light receiving part 312b form an optical path Q1 inside the accommodating part 18. The optical path Q1 extends in the X direction. Note that the light emitting part 312a and the light receiving part 312b may each have a light emitting element and a light receiving element arranged inside the accommodating part 18, or the light emitting element and the light receiving element may each be arranged outside the accommodating part 18, and the light may be guided inside and outside the accommodating part 18 by a light guiding part.

[0035] Furthermore, the light emitting unit 312a and the light receiving unit 312b are provided at the central portion of the housing unit 18 in the X direction. More specifically, the light emitting unit 312a and the light receiving unit 312b are arranged within a region corresponding to the laser passing space SP (see FIG. 5) in the X direction. The laser passing space SP is a space through which the laser light irradiated by the scanner unit 50 toward the photosensitive drum 11 passes. By providing the light emitting unit 312a and the light receiving unit 312b at the central portion of the housing unit 18 in this way, the toner remaining amount in the housing unit 18 can be detected favorably. That is, although the developer (toner) may be unevenly distributed at the ends of the housing unit 18 in the X direction, since the central portion of the housing unit 18 has less uneven distribution of the developer, the actual toner remaining amount can be detected.

[0036] In addition, in this embodiment, an LED is used for the light emitting unit 312a, and a phototransistor that is turned on by the light from the LED is used for the light receiving unit 312b, but it is not limited thereto. For example, a halogen lamp or a fluorescent lamp may be applied to the light emitting unit 312a, and a photodiode or an avalanche photodiode may be applied to the light receiving unit 312b.

[0037] The light receiving unit 312b, which is a phototransistor, receives the light emitted from the light emitting unit 312a and outputs a signal (current) corresponding to the amount of received light. This signal is converted into a voltage and input to the control unit 302 (see FIG. 15). That is, the light receiving unit 312b changes the output value based on the amount of toner (developer) stored in the housing unit 18.

[0038] The control unit 302 determines whether the light receiving unit 312b has received light from the light emitting unit 312a based on the input voltage level. When the toner in the housing unit 18 is stirred by the stirring member 60 for a certain period of time, the control unit 302 measures the length of the time during which the light receiving unit 312b detects light, and calculates the amount of toner (developer amount) in the housing unit 18. Specifically, while the stirring member 60 makes one rotation, the control unit 302 determines whether the light receiving unit 312b has received light from the light emitting unit 312a at a predetermined sampling interval (for example, at intervals of 5 milliseconds), and counts the number of times of light reception as a pulse count. Each time the stirring member 60 makes one rotation, the control unit 302 resets the pulse count and calculates the pulse count. The control unit 302 calculates the remaining toner amount using the pulse count. Further, the ROM 302b of the control unit 302 in FIG. 15(a) stores in advance a consumption threshold table in which the pulse count is associated with the remaining toner amount, and the remaining amount calculation unit 306 determines the remaining toner amount based on the pulse count and the consumption threshold table. The determined result is stored in the RAM 302c.

[0039] More specifically, as shown in FIG. 4, the optical path Q1 of the remaining amount detection unit 312 is set so as to overlap the rotation locus TC of the stirring member 60 when viewed in the axial direction of the rotation shaft 60a of the stirring member 60. In other words, the light emitted from the light emitting unit 312a of the remaining amount detection unit 312 passes through the inside of the housing unit 18 within the rotation locus TC of the stirring member 60 when viewed in the axial direction of the stirring member 60. Then, the time during which the optical path Q1 is blocked by the toner conveyed by the stirring member 60 when the stirring member 60 makes one rotation, that is, the time during which the light receiving unit 312b does not detect the light from the light emitting unit 312a, changes depending on the remaining toner amount.

[0040] That is, when the remaining toner amount is large, the optical path Q1 is easily blocked by the toner, so the time during which the light receiving unit 312b receives light becomes short. On the contrary, when the remaining toner amount is small, the time during which the light receiving unit 312b receives light becomes long. Therefore, the control unit 302 can determine the remaining toner amount level in the housing unit 18 based on the light reception time of the light receiving unit 312b in this way.

[0041] Note that the method for detecting and estimating the remaining toner amount is not limited to the above-described method, and various well-known methods for detecting and estimating the remaining toner amount can be adopted. For example, metal plates or conductive resin sheets extending in the longitudinal direction of the developing roller for two or more sheets may be arranged on the inner wall of the accommodating portion 18, and the capacitance between the two metal plates or conductive resin sheets may be measured to detect and estimate the remaining toner amount. Further, a load cell may be provided in such a manner as to support the developing container 230 from below, and the remaining toner amount may be calculated based on the weight measured by the load cell.

[0042] A detailed configuration of the supply unit 200 for mounting the supply pack 210 will be described. FIGS. 7(a) and 7(b) are perspective views of the supply unit 200 viewed from the same direction. FIG. 7(c) is a perspective view of the supply unit 200 viewed from an angle different from that of FIG. 7(a). FIGS. 8(a) and 8(b) are exploded perspective views of the supply unit 200.

[0043] As shown in FIGS. 8(a) and 8(b), the supply unit 200 includes a lever 201 (operation unit), a rotation restricting member 247, a cover 248, a sealing member 243, a main body shutter 206, and a passage member 202. The main body shutter 206 is configured to be rotatable (movable) about a rotation axis RA with respect to the passage member 202. The main body shutter 206 is disposed inside the cylindrical passage member 202 and is provided with a main body shutter opening 206a. Further, the main body shutter 206 has a main body shutter engaging portion 206b that engages with a container shutter engaged portion 214b of a container shutter 214 described later. Assuming that a virtual circle centered on the rotation axis RA is a virtual circle VC, the main body shutter engaging portion 206b is a protruding portion that protrudes inward in the radial direction r of the virtual circle VC.

[0044] When the main body shutter 206 is in the closed position (second closed position) shown in FIG. 7(a), the main body shutter opening 206a and the side surface opening 202a of the passage member 202 (see FIG. 8(b)) do not overlap. That is, the main body shutter opening 206a and the side surface opening 202a of the passage member 202 do not communicate. Therefore, the side surface opening 202a is shielded by the main body shutter 206, and toner is not discharged to the extended portion 202b of the passage member 202. When the main body shutter 206 is in the open position (second open position) shown in FIG. 7(b), the main body shutter opening 206a and the side surface opening 202a of the passage member 202 overlap. That is, the main body shutter opening 206a and the side surface opening 202a of the passage member 202 communicate. Therefore, the toner replenished from the replenishment pack 210 mounted on the replenishment unit 200 can pass through the main body shutter opening 206a and the side surface opening 202a and be discharged to the extended portion 202b of the passage member 202.

[0045] As will be described in detail later, the main body shutter 206 moves (rotates) between the closed position and the open position when the lever 201 is rotated with the replenishment pack 210 mounted on the replenishment unit 200. That is, the main body shutter 206 moves from the closed position shown in FIG. 7(a) to the open position shown in FIG. 7(b) when the lever 201 is rotated 90 degrees counterclockwise by the user.

[0046] A sealing member 243 is attached around the main body shutter opening 206a on the inner peripheral surface side of the main body shutter 206. The sealing member 243 is provided with a seal opening 243a. The sealing member 243 is attached to the main body shutter 206 such that the seal opening 243a overlaps the main body shutter opening 206a. The sealing member 243 seals the gap between the periphery of the insertion opening 212a of the insertion portion 212 of the replenishment pack 210, which will be described later, and the main body shutter 206 when the main body shutter 206 is in the open position.

[0047] The rotation restricting member 247 is fixed to the passage member 202 and is provided inside the main body shutter 206 in the radial direction r of the virtual circle VC. The rotation restricting member 247 has a rotation restricting portion 247a that engages with a rotation-restricted portion 212b of the insertion portion 212 of the supply pack 210 described later to restrict rotation about the rotation axis RA of the insertion portion 212.

[0048] The lever 201 has a ring portion 201a provided with an insertion port 201e into which the insertion portion 212 of the supply pack 210 is inserted, and a grip portion 201b provided integrally with the ring portion 201a. The lever 201 has a lever engaging portion 201d that protrudes from the inner peripheral surface forming the insertion port 201e toward the inside in the radial direction r of the virtual circle VC. As shown in FIG. 7(c), the lever engaging portion 201d as an engaging portion is in the same phase as the main body shutter engaging portion 206b in the circumferential direction of the virtual circle VC when the main body shutter 206 is in the closed position. In other words, the lever engaging portion 201d overlaps the main body shutter engaging portion 206b when viewed in the direction of the rotation axis RA when the main body shutter 206 is in the closed position. The cover 248 is fixed to the passage member 202 via the cover 248, and is a member that covers the main body shutter opening 206a when the main body shutter 206 is in the closed position as shown in FIG. 7(a).

[0049] When forming an image on the recording material P, the toner in the storage portion 18 is agitated by the agitation member 60 (see FIG. 4), and the side surface opening 202a is shielded by the main body shutter 206 so that the toner does not leak out from the side surface opening 202a of the passage member 202. Therefore, during image formation, the lever 201 is positioned at the operation position (first position) shown in FIG. 7(a) so that the main body shutter 206 is in the closed position. On the other hand, when supplying toner from the supply pack 210 described later to the storage portion 18, it is necessary to open the side surface opening 202a. Therefore, during toner supply, the lever 201 is positioned at the supply position (second position) shown in FIG. 7(b) so that the main body shutter 206 is in the open position.

[0050] (Detection of the operation position and supply position of the lever) Figs. 9(a) and 9(b) are side views showing the lever 201 and the switch 208 (detection unit). As shown in Figs. 8(a) and 9(a), the lever 201 has a detected rib 201c integrally formed with the ring portion 201a. Below the ring portion 201a, a switch 208 as a sensor is arranged. When the lever 201 is in the operating position, the switch 208 is OFF without contacting the detected rib 201c. When the lever 201 is in the supply position, the switch 208 is ON by contacting the detected rib 201c.

[0051] In this way, by turning the switch 208 OFF or ON, it is possible to detect that the lever 201 is in the operating position or the supply position. Also, by switching the switch 208 from the OFF state to the ON state, it can be detected that the lever 201 has moved from the operating position to the supply position. Further, by switching the switch 208 from the OFF state to the ON state, it can be detected that the lever 201 has moved from the supply position to the operating position.

[0052] [Supply Pack] The configuration of the supply pack 210 will be described with reference to Figs. 10(a) to 11(c). Figs. 10(a) and 10(b) are perspective views of the supply pack 210 seen from different angles. Figs. 11(a), 11(b), and 11(c) are exploded perspective views of the supply pack 210 seen from different angles. In Fig. 10(b), the insertion part opening 212a as an opening is covered by the container shutter 214 and is actually not visible, so it is shown by a dotted line.

[0053] As shown in Figs. 10(a) to 11(c), the supply pack 210 includes a pouch 211, an insertion part 212 (end member), a container shutter 214, and a container shutter seal 231. The rotation axis line RA is the rotation axis line when the container shutter 214 rotates with respect to the insertion part 212.

[0054] The pouch 211 is a container formed by making a polypropylene sheet into a bag shape through pouch processing, and it houses toner inside. The pouch 211 has a flat shape as it goes towards the side opposite to the insertion part 212, and at its end, it has a pouch end part 211a extending in a direction orthogonal to the rotation axis RA. In this embodiment, although a pouch is used as the toner storage part of the supply pack 210, a resin bottle, a container made of paper, vinyl, etc. may also be used.

[0055] The insertion part 212 is a cylindrical member that can be inserted into the insertion opening 201e of the lever 201, and an insertion part opening 212a is provided on the side surface extending in the direction of the rotation axis RA. The insertion part 212 is provided at the end of the pouch 211 in the direction of the rotation axis RA, and it is a member for discharging the toner inside the pouch 211 to the outside of the supply pack 210 through the insertion part opening 212a. The insertion part 212 further has a rotation-restricted part 212b. The rotation of the rotation axis RA of the insertion part 212 is restricted by the rotation-restricted part 212b engaging with the rotation-restricted part 247a of the rotation-restricting member 247 of the supply part 200.

[0056] The container shutter 214 is a cylindrical member configured to be concentric with the insertion part 212. The container shutter 214 is provided so as to be rotatable about the rotation axis RA with respect to the insertion part 212 on the outside of the insertion part 212 in the radial direction r of the virtual circle VC. Also, the container shutter 214 is configured to move (rotate) between a closed position (first closed position) for closing the insertion part opening 212a and an open position (second open position) for opening the insertion part opening 212a.

[0057] The container shutter 214 is formed with a container shutter opening 214c (opening). When the container shutter 214 is in the open position, the container shutter opening 214c and the insertion part opening 212a overlap and communicate with each other. At this time, toner can be discharged from the supply pack 210 to the outside of the supply pack 210 through the container shutter opening 214c and the insertion part opening 212a. When the container shutter 214 is in the closed position, the insertion part opening 212a is closed by the container shutter 214. At this time, toner is not discharged from the supply pack 210 to the outside of the supply pack 210. When the supply pack 210 is not mounted on the image forming apparatus 1, the container shutter 214 is in the closed position. Further, when the container shutter 214 is in the closed position, the rotation-restricted part 212b of the insertion part 212 is exposed from the container shutter opening 214c. This will be described later.

[0058] On the outer peripheral surface of the container shutter 214, when the supply pack 210 is mounted on the supply unit 200, a container shutter engaged part 214b that engages with the lever engaging part 201d of the lever 201 and the main body shutter engaging part 206b of the main body shutter 206 is provided. The container shutter engaged part 214b as the engaged part is a recess that is recessed inward in the radial direction r of the virtual circle VC from the outer peripheral surface of the container shutter 214, and extends to the tip of the container shutter 214 on the side far from the pouch 211 in the direction of the rotation axis RA. When the container shutter engaged part 214b receives a force in the rotational direction centered on the rotation axis RA from the lever engaging part 201d of the lever 201, the container shutter 214 is rotated with respect to the insertion part 212. Note that the container shutter engaged part 214b does not need to be a recess as long as it is configured to engage with the lever 201 and the container shutter 214 is rotated by the rotation of the lever 201.

[0059] The container shutter seal 231 is attached to the inner peripheral surface of the container shutter 214. The container shutter seal 231 seals the space between the periphery of the insertion part opening 212a of the insertion part 212 and the container shutter 214 when the container shutter 214 is in the closed position.

[0060] [Mounting and Refilling of Supply Pack] Next, with reference to FIGS. 12(a) to 13, a method of attaching the supply pack 210 to the supply unit 200 and a method of supplying toner using the supply pack 210 will be described. FIGS. 12(a) and 12(b) are perspective views of the supply unit 200 of the image forming apparatus 1 and the supply pack 210 immediately before being attached to the supply unit 200, as viewed from different directions. FIG. 13 is a perspective view showing a state where the user is holding the pouch 211 by hand.

[0061] As shown in FIGS. 12(a) and 12(b), when attaching the supply pack 210 to the supply unit 200 of the image forming apparatus 1, the supply pack 210 needs to be aligned with the supply unit 200 in two ways. This alignment is an alignment in the rotational direction around the rotation axis RA, and is possible with the container shutter 214 in the closed position. The first is an alignment between the rotation-restricted portion 212b of the insertion portion 212 exposed from the container shutter opening 214c of the container shutter 214 and the rotation-restricted portion 247a of the rotation-restricting member 247, as shown in FIG. 12(a). The second is an alignment between the container-shutter engaged portion 214b and the lever engaged portion 201d, as shown in FIG. 12(b). If this second alignment is achieved, it means that the alignment between the container-shutter engaged portion 214b and the main-body shutter engaged portion 206b has also been achieved. This is because the lever engaged portion 201d and the main-body shutter engaged portion 206b overlap when viewed in the direction of the rotation axis RA.

[0062] In a state where the attachment of the supply pack 210 to the supply unit 200 is completed, the container-shutter engaged portion 214b is engaged with the lever engaged portion 201d and is also engaged with the main-body shutter engaged portion 206b of the main-body shutter 206. Further, the rotation-restricted portion 212b of the insertion portion 212 is engaged with the rotation-restricted portion 247a. In this state, as shown in FIG. 14, when the user grasps the gripping portion 201b and rotates the lever 201 clockwise by 90 degrees, the lever 201 is rotated from the first position to the second position with respect to the insertion portion 212.

[0063] At this time, the container shutter 214 is rotated from the closed position to the open position together with the lever 201 as the engaged portion 214b of the container shutter is pushed by the lever engaging portion 201d. The main body shutter 206 is rotated from the closed position to the open position together with the lever 201 and the container shutter 214 as the engaging portion 206b of the main body shutter is pushed by the engaged portion 214b of the container shutter. Since the main body shutter 206 is configured to be rotated by the lever 201 via the container shutter 214 in this way, it does not rotate even when the lever 201 is rotated from the first position to the second position with the supply pack 210 not attached to the supply unit 200. Therefore, the main body shutter 206 does not open even if the lever 201 is operated by the user with the supply pack 210 not attached.

[0064] When the lever 201 is in the second position with the supply pack 210 attached to the supply unit 200, both the container shutter 214 and the main body shutter 206 are in the open position, and the container shutter opening 214c and the main body shutter opening 206a are in communication. In this state, as shown in FIG. 13, when the user uses a hand to open the pouch 211, the toner in the pouch 211 moves toward the insertion portion 212 together with the air. Then, the toner that has moved into the insertion portion 212 is supplied to the storage portion 18 of the developing container 230 through the insertion portion opening 212a, the container shutter opening 214c, and the main body shutter opening 206a.

[0065] When the toner replenishment is completed and the replenishment pack 210 is detached from the replenishment unit 200, as shown in FIG. 14, the user grasps the gripping portion 201b and rotates the lever 201 counterclockwise by 90 degrees. By this operation, the lever 201 is rotated from the second position to the first position with respect to the insertion portion 212. At this time, the container shutter 214 is rotated from the open position to the closed position because the container shutter engaged portion 214b is pushed by the lever engaging portion 201d and rotates together with the lever 201. The main body shutter 206 is rotated from the open position to the closed position because the main body shutter engaging portion 206b is pushed by the container shutter engaged portion 214b and rotates together with the lever 201 and the container shutter 214. The replenishment pack 210 is detached from the replenishment unit 200 with the lever 201 in the first position. In a state where the replenishment pack 210 is detached from the replenishment unit 200, since the container shutter 214 is in the closed position, toner leakage from the insertion portion opening 212a of the replenishment pack 210 can be prevented.

[0066] [Control Unit] FIG. 15(a) is a block diagram showing the hardware configuration of the control unit 302 provided in the image forming apparatus 1. The control unit 302 includes a CPU 302a as an arithmetic unit, a ROM 302b, and a RAM 302c. The CPU 302a reads various programs stored in the ROM 302b and executes processing. The RAM 302c is used as a work area for the CPU 302a.

[0067] On the input side of the control unit 302, a switch 208, a temperature sensor 9d, and a remaining amount detection unit 312 as a toner remaining amount detection unit are connected. The temperature sensor 9d detects the temperature of the fixing nip portion of the fixing unit 9. On the output side of the control unit 302, a motor 311 as an actuator and a display unit 415 are connected. Further, an I / O controller 313 as an input / output port connected to an external device is connected to the control unit 302.

[0068] The motor 311 drives the stirring member 60 and various rollers (including the photosensitive drum 11, the developing roller 12, and various conveying rollers) within the image forming apparatus 1. In this embodiment, all the rollers within the image forming apparatus 1 and the stirring member 60 are driven by a single motor 311, but it is not limited thereto. For example, the stirring member 60 and some of the rollers within the image forming apparatus 1 may be driven by the motor 311, and the other rollers may be driven by other motors. Also, a configuration may be adopted in which the motor 311 is directly connected to all the rollers and drive transmission members such as gears, and an electromagnetic clutch is provided between the motor 311 and the stirring member 60. In this case, the actuator for turning on / off the drive of the stirring member 60 is the electromagnetic clutch.

[0069] FIG. 15(b) is a block diagram showing the functional configuration of the control unit 302 provided in the image forming apparatus 1. The control unit 302 includes a temperature detection unit 303, a drive control unit 304, a transmission / reception unit 305, a remaining amount calculation unit 306, and a storage unit 315. The temperature detection unit 303 detects the current temperature of the fixing unit 9 based on the temperature detection signal 307 from the temperature sensor 9d. The drive control unit 304 drives and controls the motor 311 as necessary based on the print operation, initial control, etc. of the image forming apparatus 1.

[0070] The drivable determination unit 314 determines whether the motor 311 can be driven according to the state of the image forming apparatus 1. For example, the drivable determination unit 314 does not permit the driving of the motor 311 in the case of a jam state where the recording material P remains within the image forming apparatus 1, a failure state, or the like. The drive control unit 304 drives the motor 311 based on the determination of the drivable determination unit 314.

[0071] The remaining amount calculation unit 306 determines the remaining toner amount stored in the storage unit 18 based on the remaining amount detection signal 309 output by the remaining amount detection unit 312 disposed in the storage unit 18. The toner remaining amount determined based on the output value of this remaining amount detection unit 312 is defined as the first remaining amount. In this embodiment, since the first remaining amount is the result determined by the optical remaining amount detection method, hereinafter, it is described as the optical toner remaining amount. This optical toner remaining amount is stored in the RAM 302c. The transmission / reception unit 305 performs information transmission / reception with the I / O controller 313 that receives image information from a host such as a personal computer (not shown). The transmission / reception unit 305 transmits the remaining amount information 308 to the I / O controller 313.

[0072] Here, the remaining amount of toner is determined in percentage notation, with the necessary remaining amount of toner in product design being 0% and the amount of toner that the storage unit 18 can accommodate being 100%. Also, the remaining amount detection signal 309 is, for example, an analog signal whose voltage changes based on the remaining amount of development, or a pulse signal that outputs pulses at a certain period and whose pulse width of H / L changes according to the remaining amount of toner. In this embodiment, the remaining amount detection signal 309 output from the remaining amount detection unit 312 is the above-described pulse signal. And, a Low pulse is output when the optical path Q1 (see FIG. 4) of the remaining amount detection unit 312 is blocked by the toner in the storage unit 18, and a High pulse is output when the optical path Q1 is not blocked by the toner. The control unit 302 samples the remaining amount detection signal 309 at intervals of 5 milliseconds and counts the High pulses. The count number of the High pulses output when the member 60 rotates once is measured as the pulse count. The pulse count as the output value increases as the time during which the optical path Q1 is transmitting light is longer, that is, as the amount of toner in the storage unit 18 is less, and decreases as the time during which the optical path Q1 is blocked is longer, that is, as the amount of toner in the storage unit 18 is more. That is, the control unit 302 estimates that the amount of toner in the storage unit 18 is less as the pulse count is more, and estimates that the amount of toner in the storage unit 18 is more as the pulse count is less. The remaining amount calculation unit 306 determines the optical toner remaining amount from the pulse count and the consumption time threshold table recorded in the aforementioned ROM 302b when the image forming apparatus 1 is driven during printing or a cleaning sequence of the charging roller 17 (hereinafter referred to as during toner consumption). The consumption time threshold table is experimentally obtained and set for the relationship between the remaining amount of toner in the storage unit 18 and the pulse count. The relationship between the remaining amount of toner and the pulse count changes depending on the fluidity of the toner, that is, the pulse count changes due to variations in the toner, but the consumption time threshold table is set based on the relationship between the remaining amount of toner and the pulse count in the toner at the design center. Details will be described later.

[0073] Also, in the ROM 302b, there is a replenishment time pack type determination threshold (hereinafter also simply referred to as the determination threshold). ) is also recorded. The replenishment pack type determination threshold is preset as a threshold for determining the type of toner pack when toner is replenished after the toner remaining amount drops below 5%. After the toner replenishment from the aforementioned replenishment pack 210 is completed and the remaining amount calculation unit 306 detects that the lever 201 has moved from the replenishment position to the operation position, it determines the replenishment pack type described below based on the pulse count and the determination threshold. The replenishment pack determination threshold is obtained experimentally, and the details will be described later.

[0074] Also, the control unit 302 calculates the toner consumption amount from the pixel information of the printed image and calculates the toner remaining amount by subtracting it from the initial toner filling amount, that is, the toner filling amount at the time of new product. This toner filling amount and the toner remaining amount calculated from the pixel information are defined as the second remaining amount. Since it is the result determined by the pixel information, hereinafter, it will be described as the pixel toner remaining amount. The pixel toner remaining amount is stored in the RAM 302c.

[0075] (Optical remaining inspection priority) Then, as the user uses the image forming apparatus 1 and the toner is consumed, and the first toner replenishment is approaching, when the pixel toner remaining amount reaches 10%, the control unit 302 calculates the optical remaining inspection priority by subtracting the value of the optical toner remaining amount from the value of the pixel toner remaining amount (in this case, 10%). In this way, the control unit 302 calculates the optical remaining inspection priority when the toner is consumed from the time of new product (initial) and the pixel toner remaining amount reaches 10%. Note that, in this embodiment, in most cases, the optical remaining inspection priority is between -5% and +10% when the toner amount that can be accommodated in the accommodating unit 18 is regarded as 100%. The control unit 302 records the calculated optical remaining inspection priority in the RAM 302c. The optical remaining inspection priority is used for the replenishment pack type determination described later. In this embodiment, the optical remaining inspection priority is calculated by the above calculation, but it is not limited to this, as long as the optical toner remaining amount and the pixel toner remaining amount can be compared. For example, the difference between the optical toner remaining amount and the pixel toner remaining amount may be calculated each time the image forming apparatus 1 prints, or may be calculated immediately after detecting that the lever 201 has moved to the replenishment position.

[0076] [Toner Remaining Amount Display] Next, the toner remaining amount display of this embodiment will be described. As shown in FIG. 1, the display unit 415 is provided on the right side of the front surface of the housing 72 of the image forming apparatus 1, and displays information regarding the toner remaining amount in the housing portion 18 of the developing container 230.

[0077] FIGS. 16(a) to (d) show enlarged views of the display unit 415. As shown in FIGS. 16(a) to (d), the display unit 415 is configured to be able to light up and turn off, and is a panel member including a plurality (three in this embodiment) of scales arranged side by side vertically. As shown in FIG. 16(a), when only the lower scale is blinking, it indicates that the toner remaining amount in the housing portion 18 is at the NearOut level. As shown in FIG. 16(b), when only the lower scale is continuously lit, it indicates that the toner remaining amount in the housing portion 18 is at the Low level. As shown in FIG. 16(c), when the lower and central scales are lit and the upper scale is off, it indicates that the toner remaining amount in the housing portion 18 is at the Mid level. As shown in FIG. 16(d), when all three scales are lit, it indicates that the toner remaining amount in the housing portion 18 is at the Full level.

[0078] Note that the display unit 415 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 diffusing lens. Also, instead of providing the display unit 415 separately, the display of the toner remaining amount according to each scale as described in this embodiment may be performed on the display of the operation unit. Also, although the display unit 415 of this embodiment has three scales, the number of scales is not limited to this, and may be appropriately set according to the configuration of the image forming apparatus and the like.

[0079] Next, with reference to FIG. 17, the display switching of the display unit 415 in this embodiment will be described. FIG. 17 is a schematic diagram for explaining the threshold value for switching the display of the display unit 415 according to the detection result of the toner remaining amount in the storage unit 18 of the developing container 230 and the display pattern of the display unit 415. In the display unit 415, scale 415a as the first light-emitting unit, scale 415b as the second light-emitting unit, and scale 415c as the third light-emitting unit are provided from the bottom up.

[0080] As shown in FIG. 17, when the toner remaining amount in the storage unit 18 varies according to toner consumption and toner replenishment in the image forming mode, the control unit 302 switches the display of the display unit 415 as follows. That is, the control unit 302 determines the detection result of the toner remaining amount in the storage unit 18 based on the optical toner remaining amount and the pixel toner remaining amount, and switches the display of the display unit 415 according to the detection result. Specifically, when the detection result of the toner remaining amount in the storage unit 18 is equal to or greater than the threshold value D, the control unit 302 sets the display of the display unit 415 to the Full level (first display) in which all three scales 415a, 415b, and 415c are lit. Also, when the detection result of the toner remaining amount in the storage unit 18 is less than the threshold value D (fourth level) and equal to or greater than the threshold value C, the control unit 302 sets the display of the display unit 415 to the Mid level (second display) in which two scales 415a and 415b are lit. In this embodiment, the value of the threshold value D is set to 25%. Each of the various threshold values described below, including the threshold value D, may be appropriately set according to the capacity of the toner to be replenished and various configurations of the image forming apparatus.

[0081] When the detection result of the toner remaining amount in the storage unit 18 is less than the threshold value C (third level) (5% in this embodiment) and equal to or greater than the threshold value B, the control unit 302 sets the display on the display unit 415 to the Low level (third display) in which one scale 415a is lit. When the detection result of the toner remaining amount in the storage unit 18 by the remaining amount detection unit 312 is less than the threshold value B (second level) (0.5% in this embodiment) and equal to or greater than the threshold value A, the control unit 302 sets the display on the display unit 415 to the NearOut level (fourth display) in which the lower scale 415a blinks. When the detection result of the toner remaining amount in the storage unit 18 by the remaining amount detection unit 312 is less than the threshold value A (first level) (0% in this embodiment), the control unit 302 determines that the toner in the storage unit 18 has run out, and sets it to the toner out state in which all three scales 415a, 415b, and 415c are turned off.

[0082] That is, when the detection result of the toner remaining amount in the storage unit 18 by the remaining amount detection unit 312 is 25% or more, the control unit 302 sets the display on the display unit 415 to the first display. When the detection result of the toner remaining amount in the storage unit 18 by the remaining amount detection unit 312 is between 5% and 25%, the control unit 302 sets the display on the display unit 415 to the second display, and when it is between 0% and 5%, the control unit 302 sets the display on the display unit 415 to the third display. Also, when the detection result of the toner remaining amount in the storage unit 18 by the remaining amount detection unit 312 is between 0% and 5%, the control unit 302 sets the display on the display unit 415 to the fourth display, and when it is determined that there is no remaining amount, all the scales are turned off.

[0083] The image forming apparatus 1 in this embodiment can be equipped with various types of supply packs 210 to supply toner. For example, the image forming apparatus 1 can be equipped with a small supply pack 210 (hereinafter simply referred to as a small pack) and a large supply pack 210 (hereinafter simply referred to as a large pack). The large pack contains more toner than the small pack. In other words, the small pack as the first container is a supply pack that can contain the first amount of toner, and the large pack as the second container is a supply pack that can contain the second amount of toner, which is more than the first amount.

[0084] The small pack in this embodiment contains an amount of toner corresponding to 25% of the remaining toner amount, and the large pack contains an amount of toner corresponding to 50% of the remaining toner amount. Therefore, regardless of whether toner replenishment is performed by either the small pack or the large pack replenishment pack 210 when the remaining toner amount is less than 25%, it is necessary to switch the display on the display unit 415. Also, when the display on the display unit 415 is switched, the user can recognize that the replenishment is complete.

[0085] In this embodiment, when the small pack is replenished from the state where only the scale 415a is lit or all the scales are turned off, the remaining toner amount after replenishment is 25% or more, but it is transitioned to the Mid level where the scales 415a and 415b are lit. On the other hand, when the large pack is replenished from the state where only the scale 415a is lit or all the scales are turned off, it is transitioned to the FULL level where all the scales 415a, 415b, and 415d are lit. With this specification, the user can recognize the difference in the toner amounts between the small pack and the large pack from the state change of the display unit 415. Therefore, when toner is replenished from the state where only the scale 415a is lit or all the scales are turned off, information on whether the toner is replenished from the small pack or the large pack is required to determine to which state the scale state is to be transitioned.

[0086] Furthermore, when the user replenishes with the small pack from the state where only the scale 415a is lit or all the scales are turned off, there is room to accommodate a toner amount of 70% or more in the storage unit 18, and it is in a state where toner replenishment is possible. In this embodiment, when the small pack is replenished from the state where only the scale 415a is lit or all the scales are turned off, by transitioning to the Mid level where the scales 415a and 415b are lit, the user can recognize that it is in a state where toner replenishment is possible, and the user experience is improved.

[0087] When two of the graduations 415a and 415b are lit, since toner replenishment is not allowed any further regardless of whether the large pack or the small pack supplies toner, it is shifted to the FULL level where all the graduations 415a to 415c are lit. Therefore, it is not necessary to distinguish between the large pack and the small pack. From the above, in the present invention, when toner replenishment is performed with the remaining toner amount being 5% or less, the type of toner pack is determined. Although details will be described later, when new toner is replenished from the replenishment pack, the fluidity of the toner in the storage unit 18 changes, so the remaining toner amount after replenishment cannot be correctly determined from the consumption threshold table and the pulse count. Therefore, in order to correctly switch the display of the graduations after replenishment, it is necessary to distinguish between the large pack and the small pack based on the pack determination threshold value at the time of replenishment and the pulse count.

[0088] Also, in the present embodiment, the display unit 415 can perform a replenishment mode display shown in FIGS. 18(a) and 18(b) separately from the toner replenishment display described in FIG. 17. The replenishment mode display is for the user to recognize that the replenishment mode is being executed. As the replenishment mode display, as shown in FIG. 18(a), a pattern of repeatedly lighting one of the three graduations of the display unit 415, or as shown in FIG. 18(b), a pattern of repeatedly switching between a state where all three graduations are turned off and a state where all are lit can be considered. Also, not limited to these two patterns, for example, a pattern of repeatedly turning off the graduations one by one from a state where all three graduations are lit, or a pattern of randomly switching between the first display to the fourth display of the display unit 415 described above can also be considered. As the replenishment mode display, among the five states of the first display to the fourth display shown in FIGS. 16(a) to 16(d) and the completely turned-off state (toner out state) where none of the graduations are lit, it may be configured to repeatedly display at least two of the states. Thereby, a display that is not any of the above five states can be performed, and it is possible to visually show the user that the replenishment mode is being executed.

[0089] [Toner Fluidity and Optical Toner Remaining Amount] As described above, the image forming apparatus 1 of the present embodiment measures, as pulse count, the time during which the optical path Q1 (see FIG. 4) in the storage unit 18 is not blocked while the stirring member 60 makes one rotation, and estimates the remaining amount of toner in the storage unit 18 based on the measured pulse count. However, the toner in the storage unit 18 may have different fluidity (also referred to as toner fluidity) depending on the usage situation or the like, and even when the amount of toner in the storage unit 18 is the same, the pulse count may be different. That is, if the fluidity of the toner is different, even if the amount of toner is the same, the remaining amount of toner detected by the optical toner remaining amount detection unit 312 may change. Here, the degree of aggregation will be described as one index indicating the toner fluidity in the storage unit 18.

[0090] [Degree of aggregation] The degree of aggregation is an index indicating the ease of toner aggregation. In a state where the degree of aggregation is high, since the toner is aggregated, the toner fluidity is low. On the contrary, in a state where the degree of aggregation is low, it indicates that the toner is less likely to aggregate, and the toner fluidity is high. Such a degree of aggregation can be measured, for example, by the following method.

[0091] (Measurement of degree of aggregation) A measuring device for measuring the degree of aggregation for evaluating the fluidity of powder is, for example, the Powder Tester (registered trademark) PT-D type manufactured by Hosokawa Micron Corporation. The degree of aggregation is measured as follows. First, three types of sieves are stacked and set on the vibration table of the measuring device. The three types of sieves are, in order from the top, a 200-mesh sieve with a mesh size of 75 μm, a 390-mesh sieve with a mesh size of 38 μm, and a 635-mesh sieve with a mesh size of 25 μm. After setting these on the vibration table, 5 g of toner that has been aged overnight at 23°C and 50% humidity is vibrated on the vibration table with an amplitude of 0.6 mm for 15 seconds, and the toner remaining on each sieve is measured, and the degree of aggregation is calculated using the following formula. Mass percentage of toner remaining on the 75-μm sieve × 1 ····(a) Mass percentage of toner remaining on the 38-μm sieve × 0.6····(b) Mass percentage of toner remaining on a sieve with a mesh size of 25 μm × 0.2 ··· (c) Degree of aggregation = (a) + (b) + (c) (%)

[0092] (Toner fluidity and toner remaining amount detection) Hereinafter, the relationship between toner fluidity and toner remaining amount detection will be described. Toner fluidity tends to be inversely proportional to the degree of aggregation. Even when the amount of toner in the storage unit 18 is the same, if the toner fluidity is different, there will be a difference in the timing when the toner lifted by the stirring member 60 starts to fall downward.

[0093] When the degree of aggregation of the toner is low, the toner fluidity is high, and the toner deposited on the stirring member 60 tends to slide downward in the direction of gravity. On the other hand, when the degree of aggregation of the toner is high, the toner fluidity is low, and compared with the condition where the toner fluidity is high, the toner deposited on the stirring member 60 tends to maintain its posture. Therefore, it is difficult for the toner on the stirring member 60 to slide downward in the direction of gravity. That is, the timing when the toner on the stirring member 60 starts to fall downward is later in the condition where the toner fluidity is low than in the condition where the toner fluidity is high.

[0094] For this reason, the time during which the light receiving portion 312b of the remaining amount detection portion 312 can detect light while the stirring member 60 makes one revolution under the condition of low toner fluidity tends to be longer than that under the condition of high toner fluidity. That is, even when the amount of toner in the storage unit 18 is the same, if the toner fluidity is different, there will be a difference in the time when the light receiving portion 312b detects light. Specifically, the light receiving time of the light receiving portion 312b is short under the condition of high toner fluidity, and the light receiving time of the light receiving portion 312b is long under the condition of low toner fluidity. In other words, the pulse count of the remaining amount detection portion 312 is small under the condition of high toner fluidity (low toner aggregation degree), and the pulse count is large under the condition of low toner fluidity (high toner aggregation degree). Therefore, even when the amount of toner in the storage unit 18 is the same, the optical toner remaining amount tends to be calculated as large under the condition of high toner fluidity, and the optical toner remaining amount tends to be calculated as small under the condition of low toner fluidity.

[0095] (Change in toner aggregation degree) Next, the change in toner aggregation degree will be described. FIG. 20 is a graph showing the relationship between the number of printed sheets and the aggregation degree. In the graph of FIG. 20, the number of printed sheets is shown on the horizontal axis, and the aggregation degree is shown on the vertical axis. In FIG. 20, since the use of the new image forming apparatus 1 is started, the replenishment timing is indicated by a vertical broken line, and the aggregation degrees of each toner with different physical properties up to the number of printed sheets corresponding to approximately the second replenishment timing are shown. The solid line indicates the aggregation degree of the toner at the design center, the broken line indicates the toner with a lower tendency to increase the aggregation degree compared to the design center, and the dashed-dotted line indicates the toner with a higher tendency to increase the aggregation degree compared to the design center.

[0096] As shown in FIG. 20, the aggregation degree of the new toner is stably low regardless of the toner physical properties. However, due to the mechanical stress applied to the toner during printing and changes such as surface abrasion, the aggregation degree increases as the number of printed sheets increases. However, since the rate of increase in the aggregation degree depends on the physical properties such as the viscoelasticity of the toner, it varies. Therefore, at the replenishment timing shown in FIG. 20, the aggregation degree of the toner in the storage unit 18 differs depending on the physical properties of the toner. And as shown in FIG. 20, any type of toner converges to a predetermined aggregation degree.

[0097] Based on the characteristics of the change in toner aggregation degree described above, the consumption threshold table will be set from the relationship between the toner remaining amount and the pulse count experimentally obtained using the toner at the design center. As a result, especially until the first replenishment, the toner remaining amount detection results vary depending on the toner physical properties. However, as printing continues, the toner remaining amount can be accurately detected.

[0098] Also, as described above, the new toner contained in the supply pack 210 has a stable and low degree of aggregation regardless of the toner physical properties, and tends to have high toner fluidity. Therefore, when detecting the remaining amount of toner in the storage unit 18 that has just been replenished with toner from the new supply pack 210, the pulse count of the remaining amount detection unit 312 tends to be low (a large optical toner remaining amount is calculated). Therefore, when new toner is replenished from the supply pack 210, the degree of aggregation of the toner in the storage unit 18 becomes lower than before replenishment, that is, the pulse count becomes lower. Therefore, it is difficult to derive the replenishment time pack determination threshold value by calculation from a consumption time threshold value table or the like, and it is experimentally obtained from the pulse count results when replenishing a small pack and a large pack. Details will be described later.

[0099] [Control of the display unit in the replenishment operation] Next, the control of the display unit 415 when the replenishment operation of replenishing the storage unit 18 with toner from the supply pack 210 is performed will be described using the flowchart of FIG. 19. In step (hereinafter referred to as S) 41, the control unit 302 determines whether the lever 201 is in the replenishment position based on the detection result of the switch 208. Note that the control unit 302 may determine that the lever 201 is in the replenishment position when the opening / closing detection unit detects that the discharge tray 14 has moved from the closed position to the open position instead of the detection result by the switch 208.

[0100] In this embodiment, as described above, by mounting the supply pack 210 on the supply unit 200 and rotating the lever 201 from the operating position to the replenishment position, it becomes possible to replenish the storage unit 18 with toner from the supply pack 210. In a state where the lever 201 is in the open position, the user can open the pouch 211 of the supply pack 210 and replenish the storage unit 18 with toner. If the control unit 302 determines in S41 that the lever 201 is not in the replenishment position, the process returns to S41. When the control unit 302 detects in S41 that the lever 201 has been rotated from the operating position to the replenishment position by the switch 208, the process proceeds to S42. In S42, as described with reference to FIG. 18, the control unit 302 starts the replenishment mode display using the display unit 415. When the replenishment mode display is started, the user performs a replenishment operation such as manually opening the pouch 211, and sends toner from the pouch 211 of the replenishment pack 210 toward the storage unit 18.

[0101] In S43, the control unit 302 determines whether the lever 201 is in the operating position based on the detection result of the switch 208. That is, the control unit 302 determines whether the lever 201 has been moved from the replenishment position to the operating position. In S43, if the control unit 302 determines that the lever 201 is not in the operating position, the process returns to S43. In S43, if the control unit 302 determines that the lever 201 is in the operating position, the process proceeds to S44.

[0102] In S44, the control unit 302 determines whether the motor 311 can be driven. In S44, if the control unit 302 determines that the motor 311 cannot be driven, the process returns to S44. Note that between S41 and S43, the motor 311 is stopped. Therefore, while the user is performing the replenishment operation, no driving noise is generated from the motor 311 or gears for driving the stirring member 60, etc., making it difficult to deter the user's replenishment operation.

[0103] The control unit 302 determines that the motor 311 can be driven if the printing operation can be performed smoothly when the motor 311 is driven, and determines that the motor 311 cannot be driven if a state such as paper jams becoming more serious occurs when the motor 311 is driven. Also, the control unit 302 determines that it is in a non-drivable state even when a problem occurs in the image forming apparatus 1. Note that when all the rollers in the image forming apparatus 1 and the stirring member 60 are driven by a single motor 311 as in this embodiment, the process of S44 is necessary, but it is not limited to this. For example, when the rollers related to the conveyance of the recording material are not driven, the process of S44 is unnecessary.

[0104] In S44, when the control unit 302 determines that the motor 311 can be driven, the process proceeds to S45. In S45, the control unit 302 starts driving the motor 311. As a result, the stirring member 60 provided in the housing unit 18 is driven. Also, the control unit 302 initializes and starts a timer (not shown). In S46, the control unit 302 determines whether or not a predetermined time has elapsed since the driving of the motor 311 was started in S45 by referring to the timer. In this embodiment, the predetermined time is set to 3 seconds. The stirring member 60 levels the toner in the housing unit 18 within these 3 seconds. Levelling of the toner in the housing unit 18 by this stirring member 60 is performed in preparation for toner remaining amount detection executed in subsequent steps, but it may be omitted.

[0105] In S46, when the control unit 302 determines that the predetermined time has not elapsed, the process returns to S46, and when it determines that the predetermined time has elapsed, the process proceeds to S47. In S47, the control unit 302 starts detecting the remaining amount of toner in the housing unit 18 by the remaining amount detection unit 312, and acquires the pulse count (toner remaining amount information) of the remaining amount detection unit 312, which is the remaining amount information after replenishment. In S48, the control unit 302 performs replenishment pack type determination.

[0106] The determination of the supply pack type in S48 is to determine the types of supply packs 210 with different toner capacities. In this embodiment, the control unit 302 determines from which pack, the small pack or the large pack described above, the toner is supplied. The control unit 302 compares the pulse count by the remaining amount detection unit 312 after toner supply with the supply pack type determination threshold value. If the pulse count is equal to or greater than the determination threshold value, the control unit 302 determines that the supply pack type at the time of supply is a small pack. On the other hand, if the pulse count is less than the determination threshold value, the control unit 302 determines that the supply pack type at the time of supply is a large pack. In this embodiment, the type of the supply pack (small pack or large pack) is determined using the determination threshold value, but it is not limited to this. The control unit 302 compares the pulse count by the remaining amount detection unit 312 after toner supply with the determination threshold value. If the pulse count is equal to or greater than the determination threshold value, it can also be determined that the amount of toner supplied to the storage unit 18 at the time of supply is equal to or greater than a certain amount (predetermined amount) corresponding to the determination threshold value. On the other hand, the control unit 302 compares the pulse count by the remaining amount detection unit 312 after toner supply with the determination threshold value. If the pulse count is less than the determination threshold value, it can also be determined that the amount of toner supplied to the storage unit 18 at the time of supply is less than a certain amount corresponding to the determination threshold value. Then, the control unit 302 can also determine the supply pack type at the time of supply according to whether the supplied amount of toner is equal to or greater than a certain amount. Also, instead of determining the type of the supply pack, it may be to determine the supply amount.

[0107] Here, the details of the supply pack type determination threshold value will be described. FIG. 21 is a graph showing the degree of aggregation of toner in the storage unit 18 before supply on the horizontal axis and the pulse count after supply on the vertical axis. On the vertical axis, the solid line indicates the appropriate supply pack type determination threshold value for the toner at the design center. Here, "〇" indicates supply by a small pack, and "△" indicates supply by a large pack. Also, on the vertical axis, the broken line indicates the appropriate supply pack type determination threshold value for toner that is less likely to increase in aggregation degree compared to the design center, and the one-dot chain line indicates the appropriate supply pack type determination threshold value for toner that is more likely to increase in aggregation degree compared to the design center.

[0108] As indicated by the dashed-dotted lines '〇' and '△' at the degree of aggregation C on the horizontal axis of the graph in Fig. 21, when the degree of aggregation of the toner in the storage unit 18 before replenishment is high, the pulse count after replenishment also tends to be higher compared to the toner at the design center. Conversely, as indicated by the dashed lines '〇' and '△' at the degree of aggregation A on the horizontal axis of the graph in Fig. 21, when the degree of aggregation of the toner in the storage unit 18 before replenishment is low, the pulse count after replenishment also tends to be lower compared to the toner at the design center. As described above, since the degree of aggregation of the toner in the storage unit 18 at the time of the first replenishment varies depending on the toner physical properties, the pulse count changes in each case when replenishing small packs or large packs due to the physical properties of the toner in the storage unit 18 before replenishment. In other words, it may be difficult to determine the pack type due to the physical properties of the toner in the storage unit 18 before replenishment.

[0109] For example, the value of the pulse count after replenishment when the degree of aggregation of the toner in the storage unit 18 before replenishment is high and a large pack is replenished (△ of the dashed-dotted line) approaches the value of the pulse count after replenishment of a small pack when the degree of aggregation of the toner in the storage unit 18 is low (〇 of the dashed line). Therefore, if the value of the determination threshold is fixed regardless of the degree of aggregation, the accuracy of the replenishment pack type determination decreases (the risk of misjudgment increases). Also, for example, when the determination threshold is fixed to a value corresponding to the toner at the design center indicated by the solid line, when the degree of aggregation of the toner in the storage unit 18 before replenishment is low, it may not be possible to distinguish depending on the determination threshold fixing the '〇' and '△' indicated by the dashed line. Therefore, it is possible to improve the determination accuracy by setting an appropriate replenishment pack type determination threshold according to the degree of aggregation of the toner.

[0110] On the other hand, as shown in FIG. 22, in the process of toner consumption by printing, when the degree of aggregation of the toner in the storage unit 18 increases, the pulse count increases, so it is determined that the optical toner remaining amount decreases faster than the toner at the design center. In other words, the toner in the storage unit 18 remains in a state where it is more than the design center. Here, FIG. 22 shows the actual remaining amount of toner in the storage unit 18 on the horizontal axis, and the optical toner remaining amount and the pixel toner remaining amount on the vertical axis. In the graph of FIG. 22, the solid line indicates the pixel toner remaining amount and the optical toner remaining amount of the toner at the design center, the broken line indicates the optical toner remaining amount of the toner with a low degree of aggregation increase, and the dashed-dotted line indicates the optical toner remaining amount of the toner with an easy degree of aggregation increase.

[0111] As described above, the optical remaining inspection precedence is the value obtained by subtracting the value of the optical toner remaining amount from the pixel toner remaining amount (in this case, 10%) when the pixel toner remaining amount reaches 10%. However, as shown in FIG. 22, for the toner with an easy degree of aggregation increase, it takes a positive value. Also, when the degree of aggregation of the toner in the storage unit 18 is difficult to increase, the optical remaining inspection precedence takes a negative value. That is, the optical remaining inspection precedence indicates the ease of aggregation increase of the toner in the storage unit 18 and is a parameter for estimating the degree of aggregation of the toner in the storage unit 18. Note that for the toner at the design center, the optical remaining inspection precedence is 0.

[0112] From the above, by estimating the degree of aggregation of the toner in the storage unit 18 before replenishment from the optical remaining inspection precedence and correcting it to the appropriate replenishment time pack determination threshold at that degree of aggregation shown in FIG. 21, the accuracy of the replenishment pack type determination is improved. In this embodiment, the replenishment time pack type determination threshold is set for the cases of the optical remaining inspection precedence of -5% or less, 0%, and 10% respectively, and the replenishment time pack type determination threshold is corrected to the value linearly interpolated at 1% intervals in between. However, the method of setting the replenishment time pack type determination threshold is not limited to this, and it may be set with sufficient accuracy. For example, it may be set in two ways: whether it is 0% or more or less.

[0113] When expressed using the above-described first remaining amount and second remaining amount, the optical remaining inspection precedence is obtained by subtracting the first remaining amount from the second remaining amount. Therefore, the optical remaining inspection precedence is positive when the second remaining amount is greater than the first remaining amount, and the optical remaining inspection precedence is negative when the second remaining amount is less than the first remaining amount.

[0114] In the case of a toner with an easily increasing degree of aggregation, by correcting so that the determination threshold value becomes higher, the area determined as a large pack expands, and the area determined as a small pack becomes narrower. Therefore, when the first remaining amount is less than the second remaining amount, it can be said that the determination threshold value is corrected in the direction of determining that the toner has a large capacity among a plurality of types. On the other hand, in the case of a toner with a difficultly increasing degree of aggregation, by correcting so that the determination threshold value becomes lower, the area determined as a large pack becomes narrower, and the area determined as a small pack expands. Therefore, when the first remaining amount is greater than the second remaining amount, it can be said that the determination threshold value is corrected in the direction of determining that the toner has a small capacity among a plurality of types.

[0115] Also, the specific value of the replenishment pack type determination threshold is experimentally obtained and set to a value that can correctly determine small packs and large packs from the pulse counts when printing, small pack replenishment, and large pack replenishment are performed using toners with various physical properties, including the toner at the design center.

[0116] Then, in the second and subsequent replenishments, as shown in FIG. 20, since the degree of aggregation of the toner in the storage unit 18 converges sufficiently regardless of the toner physical properties, it is possible to accurately determine the replenishment pack type even if the replenishment pack type determination threshold is fixed.

[0117] Returning to the description of FIG. 19, when the replenishment pack type determination in S48 is completed, in S49, the control unit 302 ends the toner remaining amount detection by the remaining amount detection unit 312. In S50, the control unit 302 stops the drive of the motor 311 and stops the stirring member 60. Note that the control unit 302 may stop driving the motor 311 together with the end of the toner remaining amount detection by the remaining amount detection unit 312.

[0118] In S51, the control unit 302 switches from the replenishment mode display to the toner remaining amount display, and controls the display unit 415 based on the type of the replenishment pack determined in the replenishment pack type determination process of S48. For example, when the display unit 415 is in the first state (e.g., Low level) before the replenishment operation is performed, if it is determined in S48 that it is a small pack, the control unit 302 sets the display unit 415 to the second state (e.g., Mid level). Also, when the display unit 415 is in the first state (e.g., Low level) before the replenishment operation is performed, if it is determined in S48 that it is a large pack, the control unit 302 sets the display unit 415 to the third state (e.g., High level). For example, the first state is a state in which the first number of graduations among the graduations of the display unit 415 is lit, the second state is a state in which the second number of graduations more than the first number among the graduations of the display unit 415 is lit, and the third state is a state in which the third number of graduations more than the second number among the graduations of the display unit 415 is lit. Thus, the control of the display unit 415 in the replenishment operation is completed.

[0119] As described above, the image forming apparatus according to the present embodiment includes a plurality of toner containers, one of which can be mounted, including a first toner container that stores toner in a first toner amount and a second toner container that stores toner in a second toner amount that is larger than the first toner amount. Further, the image forming apparatus includes a mounting portion on which the toner container can be mounted, a storage portion that stores the toner replenished from the toner container mounted on the mounting portion, a detection portion that outputs an output value corresponding to the remaining toner amount stored in the storage portion, and a control portion. The control portion determines which of the first toner container and the second toner container is the toner container used for the first toner replenishment by comparing the output value immediately after the first toner replenishment, which is the toner replenishment from the toner container to the storage portion and is made from the new state of the storage portion, with a threshold value. Here, the first remaining toner amount is the remaining toner amount of the storage portion corresponding to the output value at a predetermined timing before the first toner replenishment is made. The second remaining toner amount is the remaining toner amount of the storage portion based on the toner filling amount filled in the storage portion in the new state and the image information of the images printed from the new state to a predetermined timing. The first condition is a condition that the first remaining toner amount is larger than the second remaining toner amount. The second condition is a condition that the first remaining toner amount is smaller than the second remaining toner amount. The control portion sets the threshold value so that it is more likely to be determined that the toner container used for the first toner replenishment is the first toner container when the first condition is satisfied than when the second condition is satisfied. When the output value immediately after the first toner replenishment is larger than the threshold value, the control portion determines that the toner container used for the first toner replenishment is the first toner container. When the output value immediately after the first toner replenishment is smaller than the threshold value, the control portion determines that the toner container used for the first toner replenishment is the second toner container. The threshold value is smaller when the first condition is satisfied than when the second condition is satisfied. The control portion varies the threshold value according to the difference value between the first remaining toner amount and the second remaining toner amount. The detection portion includes a light emitting portion and a light receiving portion that receives the light emitted from the light emitting portion and passing through the storage portion. The output value is a value correlated with the time received by the light receiving portion in a predetermined time.

[0120] Furthermore, the image forming apparatus includes a display unit including a plurality of scales for displaying the remaining toner amount in the storage unit, and the display unit is configured such that the number of scales displayed or lit is larger when the remaining toner amount is large than when it is small. The control unit controls the number of scales displayed or lit by comparing an output value immediately after the first toner replenishment from the toner container to the storage unit (when the storage unit is in a new state) with a threshold value. The control unit sets the threshold value such that the number of scales displayed or lit is smaller when the first condition is satisfied than when the second condition is satisfied. The control unit controls such that the number of scales displayed or lit is smaller when the output value immediately after the first toner replenishment is larger than the threshold value than when it is smaller. The above-mentioned plurality of scales includes a first scale, a second scale, and a third scale. The predetermined timing is the timing when the first scale is displayed or lit and the second and third scales are not displayed or are turned off. When the output value immediately after the first toner replenishment is larger than the threshold value, the control unit controls to display or light the second scale and turn off the third scale. When the output value immediately after the first toner replenishment is smaller than the threshold value, the control unit controls to display or light the second and third scales. The third scale, the second scale, and the first scale are arranged in this order downward in the direction of gravity.

[0121] As described above, in this embodiment, a replenishment pack type determination threshold, which is a threshold for determining the type of replenishment pack at the time of replenishment, is set based on the optical remaining inspection precedence, which is a value obtained by comparing the optical toner remaining value and the pixel toner remaining value. Thereby, it is possible to accurately discriminate between a small pack and a large pack regardless of the fluidity of the toner. Further, in this embodiment, in an image forming apparatus capable of mounting a plurality of types of toner packs having different capacities, the replenishment pack determination threshold, which is a threshold for determining the type of replenishment pack at the time of replenishment based on the optical remaining inspection precedence, which is a value obtained by comparing the optical toner remaining value and the pixel toner remaining value, is corrected. However, it is not limited to this. For example, a threshold for determining whether or not a certain amount or more of toner is replenished at the time of replenishment may be corrected based on the optical remaining inspection precedence, or it may be applied to an image forming apparatus in which only one type of toner pack can be mounted.

[0122] As described above, according to this embodiment, the type of toner container can be accurately discriminated.

Explanation of Signs

[0123] 18 Storage unit 200 Supply unit 210 Replenishment pack 302 Control unit 312 Remaining amount detection unit 415 Display unit

Claims

1. An image forming apparatus capable of mounting a plurality of toner containers including a first toner container for storing a first amount of toner and a second toner container for storing a second amount of toner greater than the first amount of toner, a mounting portion capable of mounting one of the plurality of toner containers; a storage section that stores toner supplied from the one toner container attached to the mounting section; a detection unit that outputs an output value corresponding to the remaining amount of toner contained in the container; A control unit; Equipped with the control unit determines whether the toner container used in the initial toner supply from the one toner container to the storage unit is the first toner container or the second toner container by comparing the output value immediately after the initial toner supply from the storage unit in a new state with a threshold value; a first toner remaining amount is defined as the toner remaining amount in the storage unit corresponding to the output value at a predetermined timing before the first toner replenishment, a second toner remaining amount is defined as the toner remaining amount in one of the storage units based on the amount of toner filled in the storage unit in the new state and image information of an image printed from the new state to the predetermined timing, a first condition is that the first toner remaining amount is greater than the second toner remaining amount, and a second condition is that the first toner remaining amount is smaller than the second toner remaining amount, and the control unit sets the threshold value such that it is easier to determine that the one toner container used for the first toner replenishment is the first toner container when the first condition is satisfied than when the second condition is satisfied.

1. An image forming apparatus comprising:

2. the control unit determines that the toner container used in the first toner replenishment is the first toner container when the output value immediately after the first toner replenishment is greater than the threshold value, and determines that the one toner container used in the first toner replenishment is the second toner container when the output value immediately after the first toner replenishment is less than the threshold value, The threshold value is smaller when the first condition is satisfied than when the second condition is satisfied.

2. The image forming apparatus according to claim 1,

3. the control unit varies the threshold value depending on a difference between the first remaining toner amount and the second remaining toner amount.

2. The image forming apparatus according to claim 1,

4. The detection unit has a light emitting unit and a light receiving unit that receives light emitted from the light emitting unit and passed through the storage unit, The output value is a value that is correlated with the time at which the light receiving unit receives light at a predetermined time.

2. The image forming apparatus according to claim 1,

5. An image forming apparatus to which a toner container can be attached, a mounting portion into which the toner container can be mounted; a storage section that stores toner supplied from the toner container attached to the mounting section; a detection unit that outputs an output value corresponding to the remaining amount of toner contained in the container; a display unit including a plurality of scales for displaying the remaining amount of toner in the container, the display unit being configured so that a greater number of the scales are displayed or lit when the remaining amount of toner is large than when the remaining amount of toner is small; A control unit; Equipped with the control unit controls the number of the scales to be displayed or lit by comparing the output value immediately after the first toner supply from the toner container to the storage unit from a new toner storage unit with a threshold value; a first toner remaining amount is defined as a remaining toner amount in the storage section corresponding to an output value of the detection unit at a predetermined timing before the first toner replenishment, a second toner remaining amount is defined as a remaining toner amount in the storage section based on the amount of toner filled in the storage section in the new product state and image information of an image printed from the new product state to the predetermined timing, a first condition is a condition that the first toner remaining amount is greater than the second toner remaining amount, and a second condition is a condition that the first toner remaining amount is smaller than the second toner remaining amount, and the control unit sets the threshold value such that the number of the multiple scales displayed or lit is smaller when the first condition is satisfied than when the second condition is satisfied.

1. An image forming apparatus comprising:

6. the control unit controls so that a number of the scales to be displayed or lit is smaller when the output value immediately after the first toner replenishment is larger than the threshold value than when the output value is smaller than the threshold value, The threshold value is smaller when the first condition is satisfied than when the second condition is satisfied.

6. The image forming apparatus according to claim 5,

7. the plurality of scales include a first scale, a second scale, and a third scale, the predetermined timing is a timing when the first scale is displayed or lit, and the second scale and the third scale are not displayed or turned off, the control unit controls so that, when the output value immediately after the first toner replenishment is performed is greater than the threshold value, the second scale is displayed or turned on and the third scale is turned off, and, when the output value immediately after the first toner replenishment is performed is smaller than the threshold value, the second scale and the third scale are displayed or turned on.

7. The image forming apparatus according to claim 6,

8. the third scale, the second scale, and the first scale are arranged in this order downward in a gravity direction; 8. The image forming apparatus according to claim 7,

Images