Image forming apparatus and cartridge

Abstract

To provide a developer remaining amount detection configuration that can reduce the size of the apparatus.SOLUTION: In an image forming apparatus M comprising an apparatus body 170, a first cartridge 100K removably mounted in the apparatus body 170, and a second cartridge 100C removably mounted in the apparatus body 170, the first cartridge 100K has a storage chamber 116 that stores developer, a rotation shaft 111 that is rotatably provided about a rotation axis in the storage chamber 116, a flexible member 112 that has one end and the other end in a direction intersecting the rotation axis as a free end and a fixed end fixed to the rotation shaft 111, respectively, and a magnetism generation member 113 that is fixed between the fixed end and the free end of the flexible member 112, and the second cartridge 100C has a sensor 114 for detecting the magnetism generated by the magnetism generation member 113.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This patent relates to a cartridge that is detachable from an electrophotographic image forming apparatus. [Background technology]

[0002] Electrophotographic image forming devices that use a cartridge system employ various mechanisms for detecting the remaining amount of developer toner and notifying the user when it's time to replace the cartridge. Optical and electrostatic detection methods are typical hardware methods for detecting the remaining amount of toner. Patent documents 1 and 2 propose a magnetic detection method. In a magnetic detection method, the position of a magnet placed inside a container changes depending on the amount of toner, changing the distance between the magnet and the sensor. This change in distance changes the detected voltage, estimating the toner amount. Optical detection methods require a light guide for input and output, which requires space for this light guide. Electrostatic detection methods apply high voltages to the input and output, requiring an insulation distance to prevent electrical leakage, which also requires space. In contrast, magnetic detection methods such as those disclosed in Patent documents 1 and 2 use a magnet placed inside the container as the input, eliminating the need for the light guide space or insulation distance. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-286849 [Patent Document 2] Publication number 01-032049 Summary of the Invention [Problem to be solved by the invention]

[0004] In the market for full-color image forming devices in recent years, miniaturization has become essential for product competitiveness, and there is a demand for smaller system configurations for systems that detect the amount of remaining toner.

[0005] SUMMARY OF THE INVENTION An object of the present invention is to provide a developer remaining amount detection structure that allows for the miniaturization of the device. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, an image forming apparatus according to the present invention comprises: An image forming apparatus, A device body, a first cartridge detachably attached to the main body of the apparatus, the first cartridge including: a storage chamber for storing a developer; a rotation shaft provided in the storage chamber so as to be rotatable about a rotation axis; a flexible member having one end and the other end in a direction intersecting the rotation axis as a free end and a fixed end fixed to the rotation shaft, respectively; and a magnetic generating member fixed between the fixed end and the free end of the flexible member; a second cartridge detachably attachable to the main body of the apparatus, the second cartridge having a sensor for detecting the magnetic field generated by the magnetic field generating member; The present invention is characterized by comprising: In order to solve the above-mentioned problems, the cartridge of the present invention comprises: a storage chamber for storing a developer; a rotation shaft provided in the accommodation chamber so as to be rotatable about a rotation axis; a flexible member having one end intersecting the rotation axis and the other end being a free end and a fixed end fixed to the rotation axis, respectively; a magnetic field generating member fixed between the fixed end and the free end of the flexible member; and One of a plurality of cartridges detachably mountable to a main body of an image forming apparatus, The apparatus is characterized in that it has a sensor for detecting magnetism generated by another magnetic field generating member provided in another cartridge among the plurality of cartridges attached to the apparatus main body. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a developer remaining amount detection configuration that allows the device to be made smaller. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is a cross-sectional view of the cartridge according to the first embodiment. [Figure 2] FIG. 1 is a cross-sectional view of an image forming apparatus according to a first embodiment. [Figure 3] FIG. 1 is a cross-sectional view of an image forming apparatus according to a first embodiment. [Figure 4] FIG. 1 is a cross-sectional view of an image forming apparatus according to a first embodiment. [Figure 5] FIG. 1 is a cross-sectional view of an image forming apparatus according to a first embodiment. [Figure 6] 1A and 1B are a perspective view and a cross-sectional perspective view of a cartridge according to a first embodiment. [Figure 7] FIG. 2 is a cross-sectional perspective view of the cartridge according to the first embodiment. [Figure 8] FIG. 2 is a perspective view of the periphery of a sensor of the cartridge according to the first embodiment. [Figure 9] FIG. 2 is a cross-sectional view of a tray unit in the first embodiment. [Figure 10] 4A to 4C are explanatory diagrams of a method for detecting the amount of remaining toner in the first embodiment. [Figure 11] 4A to 4C are explanatory diagrams of a method for detecting the amount of remaining toner in the first embodiment. [Figure 12] 5 is an explanatory diagram of the relationship between detection time and remaining toner amount in the first embodiment. FIG. [Figure 13] FIG. 10 is a cross-sectional view of a cartridge according to a second embodiment. [Figure 14] FIG. 10 is a cross-sectional view of a tray unit in a second embodiment. [Figure 15] 10 is an explanatory diagram of a method for detecting the amount of remaining toner in the second embodiment. FIG. [Figure 16] FIG. 10 is an explanatory diagram of the relationship between detection time and amount of waste toner in the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] The following describes in detail exemplary embodiments of the present invention with reference to the drawings. However, the dimensions, materials, shapes, and relative positions of the components described in the embodiments may be modified as appropriate depending on the configuration of the device to which the invention is applied and various conditions. In other words, the scope of the present invention is not limited to the following embodiments. Furthermore, although the embodiments describe multiple features, not all of these features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate identical or similar components, and redundant explanations will be omitted.

[0010] Example 1 An electrophotographic image forming apparatus (hereinafter also referred to as "image forming apparatus") according to a first embodiment of the present invention will be described with reference to the drawings. An electrophotographic image forming apparatus forms an image on a sheet-like recording medium such as paper using an electrophotographic image forming method. Specific examples of image forming apparatuses include copying machines, facsimile machines, printers (laser beam printers, LED printers, etc.), and combination machines (multifunction printers) of these. In the embodiment described below, a laser beam printer is exemplified as one form of an image forming apparatus.

[0011] In the first embodiment, an image forming apparatus in which four toner cartridges and four process cartridges are detachably mounted is exemplified. The number of toner cartridges and process cartridges to be mounted in the forming device is not limited to this, but may be set appropriately as needed.

[0012] A cartridge is a unit that can be fixed to or detached from the image forming apparatus (a detachable unit is also called a cartridge). Examples of the unit configuration include a unit having process means (e.g., a charging member, a developing member, a cleaning member, etc.) that acts on a photosensitive member, and a unit having toner. That is, the cartridge can take a variety of forms. Examples include a form in which an all-in-one cartridge in which a drum unit and a developing unit are integrated is replaced, and a form in which the drum unit and the developing unit are replaced separately. Alternatively, a form in which the process cartridge except for the toner container that contains toner is fixed to the image forming apparatus, and the user replaces the toner container when the toner runs out, or a form in which both the toner container and the process cartridge are replaced.

[0013] (Schematic configuration of image forming apparatus) Fig. 1 is a cross-sectional view of a cartridge 100 according to a first embodiment of the present invention. Fig. 2 is a cross-sectional view showing a schematic configuration of an image forming apparatus M according to the first embodiment of the present invention.

[0014] This image forming apparatus M is a four-color full-color laser printer that uses an electrophotographic process, and forms a color image on a recording medium S. The image forming apparatus M is of a cartridge type, and forms a color image on a recording medium S by removably mounting a cartridge 100 to an image forming apparatus main body 170.

[0015] Here, the side of the image forming apparatus M where the front door 11 is provided is referred to as the front side (front face), and the side opposite the front side is referred to as the back side (rear face). In addition, when looking at the image forming apparatus M from the front, the right side is referred to as the drive side, and the left side is referred to as the non-drive side.

[0016] 2 to 5 show a state in which the image forming apparatus M is placed on a horizontal installation surface, which is a commonly assumed installation state for the image forming apparatus M. In FIGS. 2 to 5, the horizontal direction from the front side to the back side of the image forming apparatus M is designated as the X1 direction, and the horizontal direction from the back side to the front side is designated as the X2 direction. The direction from the bottom side of the image forming apparatus M to the top side along the vertical direction (the direction of gravity) is designated as the Z1 direction, and the direction from the top side to the bottom side is designated as the Z2 direction. When viewing the image forming apparatus M from the front, the upper side is designated as the top surface, and the lower side is designated as the bottom surface. FIG. 2 is a cross-sectional view of the image forming apparatus M as viewed from the non-drive side, with the front side of the page being the non-drive side of the image forming apparatus M, the right side of the page being the front of the image forming apparatus M, and the back side of the page being the drive side of the image forming apparatus M. The same applies to FIGS. 3 to 5. Furthermore, among the directions perpendicular to the X1, X2, Z1, and Z2 directions, the direction from the non-driving side of the cartridge 100, which does not receive driving force from the image forming apparatus main body 170, to the driving side, which receives driving force, is defined as the Y1 direction, and the opposite direction to this is defined as the Y2 direction (see Figures 6 to 8).

[0017] In the image forming apparatus main body 170, first to fourth cartridges 100 (100Y, 100M, 100C, 100K) are arranged in a substantially horizontal direction.

[0018] The first to fourth cartridges 100 (100Y, 100M, 100C, 100K) each have the same electrophotographic process mechanism, but each has a different color developer (hereinafter referred to as toner). A rotational driving force is transmitted to the first to fourth cartridges 100 (100Y, 100M, 100C, 100K) from a drive output unit (main body side drum drive coupling 180 and main body side development drive coupling 185 shown in Figures 3 to 5) of the image forming apparatus main body 170. The drive output unit will be described in detail later.

[0019] Further, the first to fourth cartridges 100 (100Y, 100M, 100C, 100K) are supplied with bias voltages (charging bias, developing bias, etc.) from the image forming apparatus main body 170. supplied (not shown).

[0020] The first cartridge 100Y contains yellow (Y) toner and forms a yellow toner image (developer image) on the surface of the photosensitive drum 104. The second cartridge 100M contains magenta (M) toner and forms a magenta toner image on the surface of the photosensitive drum 104. The third cartridge 100C contains cyan (C) toner and forms a cyan toner image on the surface of the photosensitive drum 104. The fourth cartridge 100K contains black (K) toner and forms a black toner image on the surface of the photosensitive drum 104.

[0021] A laser scanner unit 14 serving as an exposure means is provided above the first to fourth cartridges 100 (100Y, 100M, 100C, and 100K). The laser scanner unit 14 outputs laser light U toward the surfaces of the photosensitive drums 104 of the first to fourth cartridges 100 (100Y, 100M, 100C, and 100K) in accordance with image information input by the user.

[0022] An intermediate transfer unit 12 serving as a transfer member is provided below the first to fourth cartridges 100 (100Y, 100M, 100C, 100K). The intermediate transfer unit 12 has a drive roller 12e, an assist roller 12c, and a tension roller 12b, and a flexible transfer belt 12a is stretched across them.

[0023] The photosensitive drum 104 of each of the first to fourth process cartridges 100 (100Y, 100M, 100C, and 100K) is positioned above the transfer belt 12a, and its outer circumferential surface is in contact with the outer circumferential surface of the annular belt-shaped transfer belt 12a. This contact area is the primary transfer area. A primary transfer roller 12d is provided for each of the cartridges 100Y, 100M, 100C, and 100K on the inside of the transfer belt 12a, facing the photosensitive drum 104. A secondary transfer roller 6 is in contact with the drive roller 12e via the transfer belt 12a. The contact area between the transfer belt 12a and the secondary transfer roller 6 is the secondary transfer area.

[0024] A paper feed unit 4 is provided below the intermediate transfer unit 12. This paper feed unit 4 has a paper feed tray 4a that holds and accommodates a stack of recording media S, and a paper feed roller 4b. As shown in FIG. 2, a fixing device 7 and a paper discharge device 8 are provided in the upper left corner of the image forming apparatus main body 170. A paper discharge tray 13 is disposed on the top surface of the image forming apparatus main body 170.

[0025] (Image formation operation) 1 and 2, the operation for forming a full-color image will be described. The photosensitive drums 104 of the first to fourth cartridges 100 (100Y, 100M, 100C, and 100K) are rotated at a predetermined speed (in the direction of arrow A in FIG. 1). The drive roller 12e is rotated by a motor (not shown) of the image forming apparatus main body 170, which moves the transfer belt 12a in the direction C in FIG. 2.

[0026] In each cartridge 100, a charging roller 105 uniformly charges the surface of the photosensitive drum 104 to a predetermined polarity and potential. The laser scanner unit 14 scans and exposes the surface of each photosensitive drum 104 with a laser beam U in accordance with an image signal for each color. As a result, an electrostatic latent image in accordance with the image signal for the corresponding color is formed on the surface of each photosensitive drum 104. The formed electrostatic latent image is developed with toner as a developer carried by a developing roller 106 that is driven to rotate at a predetermined speed.

[0027] By the above-described electrophotographic image forming process, the photosensitive drum 104 of the first cartridge 100Y is charged with yellow toner corresponding to the yellow component of a full-color image. A magenta toner image corresponding to the magenta component of the full-color image is formed on the photosensitive drum 104 of the second cartridge 100M. This toner image is then primarily transferred onto the transfer belt 12a, superimposed on the yellow toner image already transferred onto the transfer belt 12a. Similarly, a cyan toner image corresponding to the cyan component of the full-color image is formed on the photosensitive drum 104 of the third cartridge 100C. This toner image is then primarily transferred onto the yellow and magenta toner images already transferred onto the transfer belt 12a, superimposed on the yellow and magenta toner images already transferred onto the transfer belt 12a. Similarly, a black toner image corresponding to the black component of the full-color image is formed on the photosensitive drum 104 of the fourth cartridge 100K. This toner image is then primarily transferred onto the yellow, magenta, and cyan toner images already transferred onto the transfer belt 12a, superimposed on the yellow, magenta, and cyan toner images already transferred onto the transfer belt 12a. In this way, an unfixed full-color toner image of four colors, yellow, magenta, cyan, and black, is formed on the transfer belt 12a.

[0028] Meanwhile, recording media S are separated and fed one by one from paper feed unit 4 at a predetermined control timing. The recording media S are introduced into a secondary transfer section, which is a contact point between secondary transfer roller 6 and transfer belt 12a, at a predetermined control timing. As a result, as the recording media S is transported to the secondary transfer section, the four-color superimposed toner image on transfer belt 12a is transferred onto the surface of the recording media S. Then, the toner image on the recording media S to which the toner image has been transferred is fixed by a fixing means provided in fixing device 7, and the recording media S is discharged to discharge tray 13 by paper discharge device 8.

[0029] (Cartridge installation and removal configuration) The configuration for attaching and detaching the cartridge 100 will be described using Figures 3 to 5. Figure 3 is a cross-sectional view of the image forming apparatus M in a state where the front door 11 is open and the tray 171 is pulled out to the outside of the image forming apparatus main body 170. Figure 4 is a cross-sectional view of the image forming apparatus M in a state where the front door 11 is open, the tray 171 is located outside the image forming apparatus main body 170, and the toner cartridge 101 has been removed from the process cartridge 102. Figure 5 is a cross-sectional view of the image forming apparatus M in a state where the front door 11 is open, the tray 171 is located outside the image forming apparatus main body 170, and the process cartridge 102 has been removed from the tray 171.

[0030] As shown in Figures 3 to 5, tray 171 is movable in the direction of arrow X1 (pushing direction) and the direction of arrow X2 (pulling out direction), which are substantially horizontal directions, relative to image forming apparatus main body 170. That is, tray 171 is provided so as to be able to be pulled out and pushed into image forming apparatus main body 170, and is configured so as to be movable in the substantially horizontal direction when image forming apparatus main body 170 is installed on a horizontal surface. Here, the state in which tray 171 is located outside image forming apparatus main body 170 (the state in Figures 3 to 5) is referred to as the outer position. Furthermore, the state in which tray 171 is located inside image forming apparatus main body 170 with front door 11 open (the state in Figure 2) is referred to as the inner position.

[0031] As shown in FIG. 4, the toner cartridge 101 is removable from the process cartridge 102. That is, the cartridge 100 according to this embodiment is made up of the process cartridge 102 and the toner cartridge 101. When the toner runs out and printing is no longer possible, the user can replace the toner cartridge 101 with a new one filled with toner. That is, the toner cartridge 101 with the used toner is removed from the process cartridge 102, a new toner cartridge 101 is installed in the process cartridge 102, the tray 171 is pushed into the image forming apparatus main body 170, and the front door 11 is closed. This makes it possible to form images again.

[0032] As shown in FIG. 5, the tray 171 is in the outer position and is used to remove the process cartridge 102. The cartridges 100 are removable mounting portions 171Ya, 171Ma, 171Ca, and 171Ka, and the cartridges 100 of the respective colors can be mounted in the mounting portions.

[0033] When the photosensitive drum 104, developing roller 106, etc. deteriorate and print quality can no longer be maintained, the user can replace the process cartridge 102 with a new one. That is, the user removes the process cartridge 102 that needs to be replaced from any of the mounting portions 171Ya, 171Ma, 171Ca, and 171Ka of the tray 171 and installs a new process cartridge 102. Then, the user installs the toner cartridge 101, pushes the tray 171 into the image forming apparatus main body 170, and closes the front door 11. This makes it possible to form images again.

[0034] In this embodiment, the intermediate transfer unit 12 can move up and down by means of the front door 11 and a link mechanism (not shown). When the front door 11 is opened, the intermediate transfer unit 12 moves down in the direction of arrow Z2, separating the photosensitive drum 104 from the transfer belt 12a. On the other hand, when the front door 11 is closed, the intermediate transfer unit 12 moves up in the direction of arrow Z1, bringing the photosensitive drum 104 into contact with the transfer belt 12a. This allows the tray 171 to move the cartridge 100 in and out of the image forming apparatus main body 170 without the photosensitive drum 104 coming into contact with the transfer belt 12a.

[0035] As described above, the tray 171 allows a plurality of cartridges 100 to be moved together into or out of the image forming apparatus main body 170, and the toner cartridges 101 or process cartridges 102 can be easily replaced.

[0036] (Detailed cartridge configuration) 1, 6, 7, and 8, the detailed configuration of the cartridge 100 will be described. In this embodiment, the first to fourth cartridges 100 (100Y, 100M, 100C, and 100K) have the same electrophotographic process mechanism, but the colors of the toner T contained therein and the amounts of the toner T filled therein are different from each other.

[0037] The cartridge 100 is made up of a toner cartridge 101 and a process cartridge 102. The toner cartridge 101 is filled with toner T and supplies the toner T to the process cartridge 102. The process cartridge 102 uses the toner T supplied from the toner cartridge 101 to stably form a latent image on the photosensitive drum 104 and transfers the image to the intermediate transfer unit 12.

[0038] The toner cartridge 101 has a toner container 120, which contains a toner agitation shaft 121 and toner T. A toner agitation sheet 122 is attached to the toner agitation shaft 121. Although not shown, the toner cartridge 101 receives driving force from the process cartridge 102, which rotates the toner agitation shaft 121 in direction C, thereby supplying the toner T to the process cartridge 102 through a supply opening (not shown).

[0039] The process cartridge 102 is composed of a drum unit 140 and a developing unit 150 .

[0040] The drum unit 140 has a photosensitive drum 104 as a rotatable image carrier made of a photosensitive material, a charging roller 105 as a rotatable charging member, and a container 130 as a drum unit frame that holds the photosensitive drum 104 and the charging roller 105. The charging roller 105 is urged toward the photosensitive drum 104 by a charging spring 105a. Furthermore, a charge is injected into the charging roller 105 from the image forming apparatus main body 170 by a charging contact point (not shown), making it possible to uniformly charge the surface of the photosensitive drum 104. Furthermore, a photosensitive drum 104 is provided at one longitudinal end thereof with a charging spring 105a. A drum coupling 160 is provided to transmit a driving force to the ram 104. The drum coupling 160 engages with a main body side drum drive coupling 180 (shown in FIG. 3) that serves as a drum drive output portion of the image forming apparatus main body 170. This transmits the driving force of a drive motor (not shown) of the image forming apparatus main body 170 to the photosensitive drum 104, causing the photosensitive drum 104 to rotate in the direction of arrow A shown in FIG.

[0041] The developing unit 150 has a developing roller 106 as a developer carrier, a supply roller 107 as a developer supply member, a developing blade 108 as a regulating member, and a developing container 110 as a developing unit frame. The developing container 110 has a toner storage chamber 116 that stores and holds toner T, which is the developer supplied from the toner cartridge 101, and a developing chamber 117 in which the developing roller 106, the supply roller 107, and the developing blade 108 are disposed. The toner storage chamber 116 is located above the developing chamber 117, and is in communication with the developing chamber 117 via a developing opening 110b, which is a communication hole that penetrates a bottom surface 116b of the storage chamber 116 and a top surface 117b of the developing chamber 117.

[0042] An agitator shaft 111 is rotatably provided inside the toner storage chamber 116 of the developer container 110, and an agitator sheet 109, which is a flexible sheet member (flexible member), is attached to the agitator shaft 111. The developer coupling 161 shown in FIG. 6(a) engages with a main body side developer drive coupling 185 (shown in FIG. 3) serving as a drum drive output unit of the image forming apparatus main body 170. This enables the driving force of the drive motor (not shown) of the image forming apparatus main body 170 to be transmitted to the agitator shaft 111. The toner T in the toner storage chamber 116 is supplied to the supply roller 107 through a developer opening 110b formed in the developer container 110 by the rotation of the agitator shaft 111 in the direction of arrow B shown in FIG. 1. The toner T supplied to the supply roller 107 is then supplied to the development roller 106. The development blade 108 then regulates the toner T on the development roller 106 to a uniform thickness. This allows the toner to be stably supplied to the photosensitive drum 104 with which the developing roller 106 comes into contact.

[0043] The drum unit 140 and the developing unit 150 are coupled to each other so as to be rotatable relative to each other about a rotation axis SX that is parallel to the direction (Y1-Y2 direction) along which the rotation axes of the photosensitive drum 104 and the developing roller 106 extend. The drum unit 140 and the developing unit 150 are configured to receive the biasing force of a spring (not shown) to assume an abutment position (image forming position) where the photosensitive drum 104 and the developing roller 106 abut against each other. A force receiving portion 119 provided at the bottom end of the developing unit 150 is pressed by a force applying portion 190 provided in the image forming apparatus main body 170, causing the developing unit 150 to move relative to the drum unit 140 in a rotation direction SD indicated by the dashed arrow. As a result, the relative positions of the drum unit 140 and the developing unit 150 are displaced from the above-mentioned abutment position (image forming position) to a separation position (non-image forming position) where the photosensitive drum 104 and the developing roller 106 are separated from each other. The relative positions of drum unit 140 and developing unit 150 may be controlled so that they are in a separated position when image formation is not being performed, for example, when cartridge 100 is being attached or detached, and are in a contact position when image formation is being performed. In this embodiment, the drum unit 140 is fixed to image forming apparatus main body 170 (tray 171), and the developing unit 150 is rotated relative to drum unit 140, thereby changing the relative positions of the two, but the present invention is not limited to this configuration.

[0044] Here, the cartridge configuration in this embodiment is made up of a toner cartridge 101 and a process cartridge 102, but is not limited to this configuration. For example, it may be an all-in-one cartridge in which the toner cartridge 101 and process cartridge 102 are integrated. Alternatively, it may be a configuration in which a developing unit in which a developing roller and a supply roller are integrally held in a toner cartridge that holds toner, and a drum unit that holds a photosensitive drum and a charging roller are separated. The drum unit may also have a drum cleaning mechanism.

[0045] (Method for detecting remaining toner) A method for detecting the remaining amount of toner, which is a feature of this embodiment, will be described in detail using Figures 1 and 6 to 12. When a user prints, toner is consumed and the amount of toner inside cartridge 100 decreases. It is desirable to notify the user before the toner runs out completely and toner is not printed on the printed matter, resulting in a defective image. Therefore, a method for detecting the remaining amount of toner inside will be described.

[0046] As shown in FIG. 1, an agitator shaft 111 is rotatably mounted inside the toner storage chamber 116 of the developer container 110 of the process cartridge 102. A flexible sheet 112 is fixed to the agitator shaft 111. The flexible sheet 112 is a flexible sheet member, and is fixed to the agitator shaft 111 so that one end in a direction intersecting the rotation axis of the agitator shaft 111 is a free end and the other end is a fixed end. A magnet 113 is attached as a magnetic field generating member at a position away from the other end (fixed end) fixed to the agitator shaft 111, more specifically, between the other end fixed to the agitator shaft 111 and the end (free end) on the opposite side. In this embodiment, a magnet is used as the magnetic field generating member, but other materials that generate magnetic force may also be used.

[0047] FIG. 6(a) is a perspective view of the cartridge 100, and FIG. 6(b) is a cross-sectional perspective view of FIG. 6(a) taken along section K. As shown in FIG. 6(b), in this embodiment, the flexible sheet 112 is provided in the center of the agitator shaft 111 in the longitudinal direction (the Y1-Y2 direction along the rotation axis). Meanwhile, the agitator sheet 109, which aims to agitate and transport the toner in the toner storage chamber 116, is provided with a width that spans almost the entire longitudinal area of ​​the toner storage chamber 116. The flexible sheet 112 is preferably provided with a minimum width in the longitudinal direction of the toner storage chamber 116 so as not to affect the accuracy of detecting the remaining toner amount (i.e., so that movement of the flexible sheet 112 does not significantly change the toner storage state). The shape and material of the magnet 113 and the shape, material, and thickness of the flexible sheet 112 can be selected appropriately according to the characteristics.

[0048] A magnetic sensor 114 that detects magnetism is attached to the container 130 of the process cartridge 102. Here, this magnetic sensor 114 is not for detecting the magnetism of the magnet 113 provided in the attached process cartridge 102, but for detecting the magnetism of the magnet 113 provided in another adjacent process cartridge 102 (see FIG. 9).

[0049] Fig. 7 is a cross-sectional perspective view of the cartridge 100, taken at a position different from cross section K in Fig. 6(b), and is a diagram illustrating the configuration around the magnetic sensor 114. Fig. 8 is an enlarged perspective view of the cartridge 100 for illustrating the configuration around the magnetic sensor 114.

[0050] As shown in FIGS. 7 and 8, the magnetic sensor 114 is held by a holder 114a. The holder 114a has guided portions 114b, which are shaft portions that protrude in the same direction from both ends in the direction (Y1 and Y2 directions) along the extension of the rotation axis of the agitator shaft 111. The container 130 includes a holder guide 114c as a guide portion and a sensor spring 115 as a biasing member. The holder guide 114c and the sensor spring 115 form a biasing support portion that supports the holder 114a so that a biasing force acts on the holder 114a to press the holder 114a against the outer wall surface of another developing container 110 of another adjacent cartridge 100.

[0051] The holder guide 114c is recessed in a direction (Y1, Y2 direction) along the direction of extension of the rotation axis of the stirring shaft 111, and has guide grooves 114d that extend in a direction that moves the holder 114a toward and away from another developing container 110 of another adjacent cartridge 100. The guide grooves 114d are arranged on both sides of the holder 114a in the Y1, Y2 direction, facing each other, and a pair of guided portions 114b provided on both sides of the holder 114a in the same direction are inserted into the guide grooves 114d. The guide portion 114b is guided by the guide groove 114d, so that the holder 114a is movable in a direction approaching and a direction separating from the other developing container 110 (approaching and separating direction).

[0052] The sensor spring 115 is attached between the back surface of the holder 114a and the container 130. The sensor spring 115 applies a biasing force to the back surface of the holder 114a opposite to the side where the magnetic sensor 114 is exposed to the outside, and biases the holder 114a in a direction toward the other developing container 110. By receiving this biasing force, the holder 114a comes into contact with the other developing container 110, and the magnetic sensor 114 held by the holder 114a faces the outer surface of the other developing container 110.

[0053] 4 and 5, the abutting state between the holder 114a and another developing container 110 is automatically formed when each cartridge 100 is mounted on the tray 171. That is, the other cartridge 100 is configured to be able to be mounted on the tray 171 while the outer wall surface of the other developing container 110 pushes the holder 114a away in the separation direction against the biasing force of the sensor spring 115. This makes it possible to form a state in which the holder 114a abuts on the developing container 110 of the adjacent cartridge 100 by mounting the cartridge 100.

[0054] 1 and 9, a configuration in which the magnetic sensor 114 detects the magnetism of the magnet 113 will be described. Fig. 9 is a schematic cross-sectional view (cross-sectional view along the X1, X2, Z1, and Z2 directions perpendicular to the rotation axis of the photosensitive drum 104, etc.) showing the tray 171 and the first to fourth cartridges 100Y, 100M, 100C, and 100K attached to the tray 171.

[0055] In this embodiment, of the first to fourth cartridges 100Y, 100M, 100C, and 100K, the fourth cartridge 100K is equipped with a magnet 113K as a magnetic generating member but is not equipped with a magnetic sensor. The first to third cartridges 100Y, 100M, and 100C are equipped with a magnetic sensor 114 for detecting the remaining amount of toner in an adjacent cartridge 100. The multiple cartridges 100 are arranged so as to be aligned along the X1-X2 direction, which is the first direction. The magnetic sensor 114 is provided on the cartridge frame of the cartridge 100 that includes it, on the side closer to the cartridge frame of the adjacent cartridge 100, in the alignment direction (X1-X2 direction) of the multiple cartridges 100, so as to face the cartridge frame of the adjacent cartridge 100. That is, the magnetic sensor 114 is provided in the container 130 of the drum unit 140 and the developer container 110 of the developing unit 150, which constitute the cartridge frame, and faces the outer surface of the container 130 of another cartridge 100. The magnetism of the magnet 113Y included in the first cartridge 100Y is detected by a magnetic sensor 114H provided in the tray 171.

[0056] 9, the magnetic field of the magnet 113K of the fourth cartridge 100K containing black (K) toner is detected by a magnetic sensor 114C held by the third cartridge 100C. At this time, a holder 114aC holding the magnetic sensor 114C is biased by a sensor spring 115 so as to abut against the outer wall surface of the developing container 110.

[0057] In relation to the third cartridge 100C and the fourth cartridge 100K, the third cartridge 100C corresponds to the second cartridge of the present invention, and the fourth cartridge 100K corresponds to the first cartridge of the present invention. The cartridge frame (developing container 110C, container 130C) of the third cartridge 100C corresponds to the second frame of the present invention, and the cartridge frame (developing container 110K, container 130K) of the fourth cartridge 100K corresponds to the first frame of the present invention. In addition, the toner storage chamber 116C of the developing container 110C corresponds to the second storage chamber of the present invention, the agitating shaft 111 corresponds to the second rotating shaft of the present invention, and the flexible sheet The agitator shaft 111 corresponds to the first rotating shaft of the present invention, the flexible sheet 112 corresponds to the first flexible member of the present invention, and the magnet 113C corresponds to the second magnetic field generating member of the present invention. In the developing container 110K, the toner storage chamber 116K corresponds to the first storage chamber of the present invention, the agitator shaft 111 corresponds to the first rotating shaft of the present invention, the flexible sheet 112 corresponds to the first flexible member of the present invention, and the magnet 113K corresponds to the first magnetic field generating member of the present invention. In the third cartridge 100C, the photosensitive drum 104 corresponds to the second photosensitive drum, the drum unit 140 corresponds to the second drum unit, the developing roller 106 corresponds to the second developing roller, and the developing unit 150 corresponds to the second developing unit. In the fourth cartridge 100K, the photosensitive drum 104 corresponds to the first photosensitive drum, the drum unit 140 corresponds to the first drum unit, the developing roller 106 corresponds to the first developing roller, and the developing unit 150 corresponds to the first developing unit.

[0058] 9, the magnetic field of the magnet 113C of the third cartridge 100C is detected by a magnetic sensor 114M held by the second cartridge 100M. At this time, a holder 114aM holding the magnetic sensor 114M is biased by a sensor spring 115 so as to abut against the outer wall surface of the developing container 110C.

[0059] In the relationship between the second cartridge 100M and the third cartridge 100C and the present invention, the second cartridge 100M corresponds to the second cartridge of the present invention, and the third cartridge 100C corresponds to the first cartridge of the present invention. Therefore, the relationship between each part of the second cartridge 100M and the third cartridge 100C and the present invention is the same as the relationship between the third cartridge 100C and the fourth cartridge 100K and the present invention, as described above.

[0060] In addition, in relation to the second to fourth cartridges 100M, 100C, and 100K and the present invention, if the third cartridge 100C corresponds to the second cartridge of the present invention, the second cartridge 100M corresponds to the third cartridge of the present invention. In this case, the magnetic sensor 114C corresponds to the second sensor of the present invention, and the magnetic sensor 114M corresponds to the third sensor of the present invention.

[0061] 9, the magnetic field of the magnet 113M of the second cartridge 100M is detected by a magnetic sensor 114Y held by the first cartridge 100Y. At this time, a holder 114aY holding the magnetic sensor 114Y is biased by a sensor spring 115 so as to abut against the outer wall surface of the developing container 110M.

[0062] In relation to the present invention, the first cartridge 100Y and the second cartridge 100M correspond to the second cartridge of the present invention, and the second cartridge 100M corresponds to the first cartridge of the present invention. Therefore, the relationship between the components of the first cartridge 100Y and the second cartridge 100M and the present invention is similar to the relationship between the third cartridge 100C and the fourth cartridge 100K and the present invention, as described above.

[0063] In addition, in relation to the first to third cartridges 100Y, 100M, and 100C and the present invention, if the second cartridge 100M corresponds to the second cartridge of the present invention, the first cartridge 100Y corresponds to the third cartridge of the present invention. In this case, the magnetic sensor 114M corresponds to the second sensor of the present invention, and the magnetic sensor 114Y corresponds to the third sensor of the present invention.

[0064] 9, the magnetic force of the magnet 113Y of the first cartridge 100Y is detected by a magnetic sensor 114H held by the tray 171. At this time, a holder 114aH holding the magnetic sensor 114H is positioned so as to come into contact with the outer wall surface of the developing container 110Y. As shown, the sensor is biased by a sensor spring 115.

[0065] In relation to the first and second cartridges 100Y and 100M and the tray 171, the magnetic sensor 114Y corresponds to the second sensor of the present invention, and the magnetic sensor 114H corresponds to the fourth sensor of the present invention.

[0066] 10(a) to 11(c), a method for estimating the toner amount will be described. Here, one cartridge 100 will be described, but the toner amount is detected in the same manner for all of the first to fourth cartridges.

[0067] 10(a) to 10(c) are schematic cross-sectional views of the cartridge 100 when the developer container 110 is nearly full of toner T. FIGS. 10(a) to 10(c) show the state when the magnet 113, which moves with the rotation of the agitator shaft 111, passes through the detection range R of the magnetic sensor 114 provided in the adjacent cartridge 100. FIG. 10(b) shows the state when the magnet 113 has reached the position closest to the magnetic sensor 114 disposed in the adjacent cartridge. FIG. 10(a) shows the state when the agitator shaft 111 has rotated slightly earlier than in FIG. 10(b). FIG. 10(c) shows the state when the agitator shaft 111 has rotated slightly later than in FIG. 10(b).

[0068] 11(a) to 11(c) are schematic cross-sectional views of the cartridge 100 when there is almost no toner T in the developing container 110. FIGS. 11(a) to 11(c) show the state when the magnet 113, which is moved by the rotation of the agitator shaft 111, passes through the detection range R of the magnetic sensor 114 provided in the adjacent cartridge 100. FIG. 11(b) shows the state when the magnet 113 has reached the position closest to the magnetic sensor 114 arranged in the adjacent cartridge. FIG. 11(a) shows the state when the agitator shaft 111 has rotated slightly earlier than in FIG. 11(b). FIG. 11(c) shows the state when the agitator shaft 111 has rotated slightly later than in FIG. 11(b).

[0069] The flexible sheet 112 is made of as thin a sheet material as possible (in this embodiment, a 50 μm thick PET or PPS sheet) so as not to affect the accuracy of detecting the remaining toner amount (so that the movement of the flexible sheet 112 does not significantly change the toner storage state). Therefore, as shown in FIGS. 10(a) to 10(c), in the developing container 110 to which the toner T is abundantly supplied from the toner cartridge 101, the toner T acts as resistance, and when the stirring shaft 111 rotates in the B direction, the flexible sheet 112 rotates while bending. Therefore, at the position where the magnet 113 is closest to the magnetic sensor 114 (FIG. 10(b)), the magnet 113 is separated by a distance L1.

[0070] On the other hand, as shown in FIGS. 11(a) to 11(c), when the toner T inside the toner cartridge 101 runs out, the toner T is not supplied to the developing container 110. When the toner T in the developing container 110 is low, the toner T that was acting as resistance is no longer present, so the amount of bending of the flexible sheet 112 decreases, and as shown in FIG. 11(b), the magnet 113 can approach the magnetic sensor 114. If this distance is L2, then L1 > L2. In other words, the behavior of the magnet 113 changes depending on the amount of toner T in the developing container 110, and the time it takes for the magnetic sensor 114 to detect the magnetism emitted by the magnet 113 (hereinafter referred to as the detection time) also changes.

[0071] 12(a) is a schematic diagram illustrating that the time it takes for the magnetic sensor 114 to detect the magnetism of the magnet 113 changes depending on the amount of toner. The dashed-dotted arrow TrF in FIG. 12(a) indicates the movement locus of the magnet 113 when the magnet 113 passes through the detection range R of the magnetic sensor 114 when the developer container 110 is nearly full of toner T. The dashed-dotted arrow TrL in FIG. 12(a) indicates the movement locus of the magnet 113 when the magnet 113 passes through the detection range R of the magnetic sensor 114 when the toner T in the developer container 110 is low. The figure shows the movement trajectory of 113.

[0072] 12(a), when the toner tank is full, the movement locus TrF of the magnet 113 passes through a position farther away from the magnetic sensor 114 due to resistance from the toner, and the period of time spent in the detection range R of the magnetic sensor 114 is shorter. On the other hand, when the toner tank is low, the movement locus TrL of the magnet 113 passes through a position closer to the magnetic sensor 114 due to less resistance from the toner, and the period of time spent in the detection range R of the magnetic sensor 114 is longer. In other words, the less the amount of toner, the closer the magnet 113 can be to the magnetic sensor 114, and therefore the detection time is longer as the amount of toner is smaller.

[0073] Figure 12(b) specifically shows the relationship between the amount of toner in the developing container 110 and the detection time of the magnetic sensor 114. The horizontal axis of the graph in Figure 12(b) represents the amount of toner in the developing container 110, and the vertical axis represents the detection time. Since the toner T in the developing container 110 is consumed and decreases, the actual amount of toner changes from right to left on the page in Figure 12(b).

[0074] As shown in FIG. 12(b), the toner amount and detection time are proportional until the toner amount decreases to a certain extent, making it possible to estimate the toner amount (part D). When the toner amount is further reduced than in FIG. 11 (part E in FIG. 12(b)), the remaining toner amount is extremely low, and the flexible sheet 112 does not bend due to the toner T, making it difficult to detect the remaining toner amount using the detection configuration of this embodiment. Therefore, when the remaining toner amount becomes extremely low, it is possible to estimate the remaining toner amount by switching to a method of detecting the remaining toner amount based on an image pattern, for example. While this method may result in accumulated errors, in this embodiment, it is only necessary to estimate the small amount of toner that is almost gone and missing, so the effect of errors is extremely small. This allows the toner amount to be detected with high accuracy until the toner filled in the developer container 110 is consumed and the toner is completely depleted.

[0075] Furthermore, the remaining toner amount detection configuration of this embodiment enables further space saving and miniaturization in a full-color image forming apparatus. In a normal tandem image forming apparatus, a predetermined gap is provided between adjacent cartridges, but in this embodiment, as shown in Figures 2 and 9, the above gap is utilized to place the magnetic sensor 114.

[0076] As shown in FIG. 1 , in the horizontal direction (X1-X2 direction) substantially along the line-up direction of the cartridges 100, the magnetic sensor 114 is located closer to the developing container 110 of the adjacent cartridge 100 than the charging roller 105. Specifically, in the horizontal direction, the position of the magnetic sensor 114 (a virtual perpendicular line VL4 passing through the magnetic sensor 114) is located downstream in the X2 direction from the position of the charging roller 105 (a virtual perpendicular line VL5 passing through the charging roller 105). Furthermore, in the vertical direction (Z1-Z2 direction), the magnetic sensor 114 is located higher than the charging roller 105. Specifically, in the vertical direction, the position of the magnetic sensor 114 (a virtual line HL4 passing through the magnetic sensor 114) is located higher than the position of the charging roller 105 (a virtual line HL5 passing through the charging roller 105). This position of the magnetic sensor 114 corresponds to the dead space formed around the charging roller 105 between adjacent cartridges 100. According to this embodiment, the magnetic sensor 114 can be arranged so as to fill the dead space, thereby saving space and achieving miniaturization.

[0077] Furthermore, the above-mentioned magnetic sensor 114 is required to be disposed so as not to detect the magnetism of the magnet 113 provided in the cartridge 100 provided with the magnetic sensor 114, but to be able to detect the magnetism of the magnet 113 provided in the adjacent cartridge 100. As shown in FIG. 9, the magnetic sensor 114 is disposed so as to be aligned with the toner storage chamber 116 in the arrangement direction (first direction) of the cartridges 100, which is a direction substantially along the horizontal direction (X1, X2 direction). That is, When viewed in the vertical direction (Z1-Z2 direction), the magnetic sensor 114 is provided at a height that overlaps with the toner storage chamber 116. Furthermore, in the vertical direction (Z1-Z2 direction), the position of the magnetic sensor 114 (a virtual line HL4 passing through the magnetic sensor 114) is higher than the position of the bottom surface 116b of the toner storage chamber 116 (a virtual line HL6 passing through the bottom surface 116b). Furthermore, when viewed in the horizontal direction (X1-X2 direction), the magnetic sensor 114 is provided at a height that overlaps with the agitator shaft 111. With this configuration, even if the magnetic sensor 114 is an inexpensive sensor with a relatively narrow detection range R, it can be positioned so that the less toner stored in the toner storage chamber 116, the longer the time it can detect magnetism during rotation of the agitator shaft 111. This allows for cost reduction.

[0078] By detecting the amount of toner in the developing container with the above configuration, it is possible to stably detect the amount of remaining toner even in a small, low-end color product. Note that, although a cartridge-type process cartridge is exemplified in this embodiment, the process cartridge may also be configured such that the developing device is fixed to the image forming apparatus.

[0079] Example 2 A second embodiment of the present invention will be described. Here, the configuration and operation of the second embodiment that differ from the first embodiment will be described, and the same reference numerals will be used to designate components having the same configuration and function as the first embodiment, and the repeated description will be omitted. In the second embodiment, matters that are not particularly described here are the same as those in the first embodiment.

[0080] In this embodiment, an example will be described in which the remaining toner amount detection configuration of the present invention is applied to estimation of the amount of waste toner after use.

[0081] (Detailed cartridge configuration) 13 and 14, the detailed configuration of the cartridge 200 will be described. In this embodiment, the first to fourth process cartridges 200 (200Y, 200M, 200C, 200K) have similar electrophotographic process mechanisms, but the colors of the toner T contained therein and the amounts of the toner T filled therein are different from each other.

[0082] The all-in-one cartridge 200 has a rotatable photosensitive drum 104 made of a photosensitive member, a container 230 that holds the photosensitive drum 104, and a rotatable charging roller 105, and the charging roller 105 is urged toward the photosensitive drum 104 by a charging spring 105a. Furthermore, an electric charge is injected into the charging roller 105 from the image forming apparatus main body 170 by a charging contact point (not shown), enabling the surface of the photosensitive drum 104 to be uniformly charged. Furthermore, the method of driving the photosensitive drum 104 is the same as in the first embodiment, and therefore will not be described here.

[0083] The cartridge 200 also has a developing container 210 that holds toner T. Inside the developing container 210, there is an agitating shaft 111, and an agitating sheet 109 is attached to the agitating shaft 111. The method for stably supplying the toner T in the developing container 210 to the drum is the same as in the first embodiment, and therefore will not be described here.

[0084] The cartridge 200 also has a cleaning member 201 fixed to the container 230. The cleaning member 201 is a member for removing residual toner T1 remaining on the surface of the photosensitive drum 104 after the primary transfer. The residual toner T1 removed from the photosensitive drum 104 by the cleaning member 201 can be collected by collecting the residual toner T1 in a waste toner section 240 serving as a storage chamber formed in the container 230.

[0085] Here, the cartridge configuration of this embodiment is an all-in-one cartridge, but is not limited to this configuration. The toner cartridge may be configured as a process cartridge having a developing roller, a supply roller, a drum, a charging roller, and a cleaning member, or may be configured as a separate developing unit having a developing roller, a supply roller, and toner, and a drum unit having a photosensitive drum, a charging roller, and a cleaning member.

[0086] (Method for detecting remaining toner) 13 to 16, a method for detecting the remaining amount of toner, which is a feature of this embodiment, will be described in detail. When a user prints, toner is consumed, and the remaining toner T1 remaining on the drum surface is collected by cleaning member 201 into waste toner section 240 of container 230. The capacity of waste toner section 240 is limited, so it is necessary to notify the user before the waste toner becomes full. Therefore, in this embodiment, a configuration will be described that detects the amount of waste toner, making it possible to notify the user before the waste toner becomes full.

[0087] As shown in FIG. 13 , an agitator shaft 211 is rotatably attached to a waste toner section (waste toner storage chamber) 240 of a container 230. The agitator shaft 211 can rotate in the direction F by a driving input (not shown). A flexible sheet 212 is fixed to the agitator shaft 211. The flexible sheet 212 is a flexible sheet member (flexible member), and is fixed to the agitator shaft 211 so that one end of the flexible sheet 212 in a direction intersecting the rotation axis of the agitator shaft 211 is a free end and the other end is a fixed end. A magnet 213 is attached as a magnetic field generating member to the flexible sheet 212 at a position away from the other end (fixed end) fixed to the agitator shaft 211, more specifically, between the other end fixed to the agitator shaft 211 and the other end (free end) on the opposite side. In this embodiment, a magnet is used as the magnetic field generating member, but other materials that generate magnetic force may also be used.

[0088] Further, a magnetic sensor 214 for detecting magnetism is attached to the developing container 210. Here, this magnetic sensor 214 is not for detecting the magnetism of the magnet 213 provided in the attached cartridge 200, but for detecting the magnetism of the magnet 213 provided in another adjacent cartridge 200 (see FIG. 14). As in the first embodiment, in this embodiment as well, the shape and material of the magnet 213 and the shape, material and thickness of the flexible sheet 212 can be selected appropriately according to the characteristics.

[0089] 13, the magnetic sensor 214 is held by a holder 214a. The container 130 includes a biasing support portion that supports the holder 214a so as to apply a biasing force to the holder 214a, pressing the holder 214a against the outer wall surface of another container 230 of another adjacent cartridge 200. The specific configuration of the biasing support portion, including the sensor spring 215 that applies the biasing force, is the same as in the first embodiment, and therefore a description thereof will be omitted.

[0090] 13 and 14, the configuration in which the magnetic sensor 214 detects the magnetism of the magnet 213 will be described. Fig. 14 shows the cartridges 200 of each color mounted on the tray 271. The magnetic sensor 114 is disposed at one end of the developing container 210 in the direction in which the multiple cartridges 200 are lined up (X1, X2 direction), and the magnet 213 is disposed in the waste toner section 240 of the container 230 of the cartridge 200.

[0091] The magnetic field of the magnet 213Y of the first cartridge 200Y containing yellow (Y) toner is detected by a magnetic sensor 214M held by the second cartridge 200M. At this time, the magnetic sensor 214M is biased toward the container 230 of the first cartridge 200Y by a sensor spring 215 shown in FIG.

[0092] Similarly, the magnetism of the magnet 213M of the second cartridge 200M is detected by the magnetic sensor 214C held by the third cartridge 200C. The magnetic sensor 214C is biased by the sensor spring 215 toward the container 230 of the second cartridge 200M. It is the same as the Air Sensor 214M.

[0093] The magnetic field of the magnet 213C of the third cartridge 200C is detected by a magnetic sensor 214K held by the fourth cartridge 200K. The magnetic sensor 214K is biased toward the container 230 of the third cartridge 200C by a sensor spring 215, similar to the magnetic sensors 214M and 214C.

[0094] The magnetism of the magnet 213K of the fourth cartridge 200K is detected by a magnetic sensor 214H held on the tray 271. The magnetic sensor 214H is urged toward the container 230 of the fourth cartridge 200K by a sensor spring 215, similar to the magnetic sensors 214M, 214C, and 214K.

[0095] A method for estimating the toner amount will be described with reference to Figures 15 and 16. Here, one cartridge 200 will be described, but the amount of waste toner is detected in the same manner for any of the first to fourth cartridges.

[0096] 15(a) is a cross-sectional view showing a state where the agitator shaft 211 rotates in the direction F when there is almost no waste toner T1 in the waste toner section 240 of the container 230, and the magnet 213 comes to the position closest to the magnetic sensor 214 arranged in the adjacent cartridge. FIG. 15(b) is a cross-sectional view showing a state where the agitator shaft 211 rotates in the direction F when the waste toner section 240 of the container 230 is nearly full of waste toner T1, and the magnet 213 comes to the position closest to the magnetic sensor 214 arranged in the adjacent cartridge.

[0097] As shown in FIG. 15(a), when the cartridge 200 has just been used, the amount of waste toner T1 stored inside the waste toner section 240 of the container 230 is small. At this time, the waste toner T1 does not create resistance to the flexible sheet 212, so the flexible sheet 212 is less likely to bend, allowing it to approach the magnetic sensor 214. After the cartridge 200 has been used for a long time, the state shown in FIG. 15(b) occurs when the waste toner T1 is nearly full. The flexible sheet 212 is made of as thin a sheet material as possible (in this embodiment, a PET or PPS sheet with a thickness of 50 μm). Therefore, as shown in FIG. 15(b), the waste toner T1 creates resistance, and when the agitator shaft 211 rotates in the F direction, the flexible sheet 212 rotates while bending. Therefore, the distance between the magnet 213 and the magnetic sensor 214 increases, resulting in a relationship of L4>L3.

[0098] In this way, the behavior of magnet 213 changes depending on the amount of waste toner T1 in waste toner section 240 of container 230, and the detection time of magnetic sensor 214 for the magnetism emitted by magnet 213 also changes. That is, the smaller the amount of waste toner, the closer magnet 213 can be to magnetic sensor 214, and therefore the smaller the amount of waste toner, the longer the detection time.

[0099] Figure 16 specifically shows the relationship between the amount of waste toner in waste toner section 240 of container 230 and the detection time of magnetic sensor 214. The horizontal axis of the graph in Figure 16 represents the amount of waste toner remaining in waste toner section 240, and the vertical axis represents the detection time. Since waste toner T1 in waste toner section 240 of container 230 increases as cartridge 200 is used, the actual amount of waste toner changes from left to right on the page in Figure 16.

[0100] As shown in Figure 16, when there is little waste toner (part G), it cannot be detected, but as the waste toner increases (part H), the detection time and the amount of waste toner become proportional, making it possible to estimate the amount of waste toner.

[0101] By detecting the amount of waste toner in the waste toner section with the above-mentioned configuration, it is possible to notify the user before the waste toner section becomes full, and it is possible to provide a product with good usability. The remaining amount of toner can be detected, and stable detection of the amount of waste toner can be performed even in small, low-end color products. Note that, in this embodiment, as in the first embodiment, a cartridge-type process cartridge is exemplified, but the process cartridge may also be configured such that the developing device is fixed to the image forming apparatus.

[0102] The above-described embodiments can be combined with each other.

[0103] The disclosure of the embodiments of the present invention includes the following configurations. (Configuration 1) An image forming apparatus, A device body, a first cartridge detachably attached to the main body of the apparatus, the first cartridge including: a storage chamber for storing a developer; a rotation shaft provided in the storage chamber so as to be rotatable about a rotation axis; a flexible member having one end and the other end in a direction intersecting the rotation axis as a free end and a fixed end fixed to the rotation shaft, respectively; and a magnetic generating member fixed between the fixed end and the free end of the flexible member; a second cartridge detachably attachable to the main body of the apparatus, the second cartridge having a sensor for detecting the magnetic field generated by the magnetic field generating member; An image forming apparatus comprising: (Configuration 2) the first cartridge and the second cartridge are aligned in a first direction; 2. The image forming apparatus according to claim 1, wherein the sensor is provided between the first cartridge and the second cartridge in the first direction. (Configuration 3) the first cartridge has a first frame that defines the storage chamber, and a developing roller that is configured to carry the developer in the storage chamber, the second cartridge has a photosensitive drum and a second frame that rotatably supports the photosensitive drum, 3. The image forming apparatus according to claim 1, wherein the sensor is supported by the second frame so as to face the first frame in the first direction. (Configuration 4) When the photosensitive drum, the storage chamber, and the developing roller are respectively a second photosensitive drum, a first storage chamber, and a first developing roller, the first cartridge has a first photosensitive drum configured to receive developer from the first developing roller; The second cartridge has a second storage chamber that stores developer, and a second developing roller that carries the developer in the second storage chamber and is configured to supply the developer to the second photosensitive drum. 4. The image forming apparatus according to any one of configurations 1 to 3. (Configuration 5) the first cartridge includes a photosensitive drum, a cleaning member that removes developer from the photosensitive drum, and a first frame that rotatably supports the photosensitive drum and also supports the cleaning member; the storage chamber is formed by the first frame and is a storage chamber that stores the developer removed from the photosensitive drum by the cleaning member, the second cartridge has a developing roller configured to carry a developer, and a second frame that rotatably supports the developing roller; The image forming apparatus according to any one of configurations 1 to 4, wherein the sensor is supported by the second frame so as to face the first frame in the first direction. (Configuration 6) When the photosensitive drum, the storage chamber, and the developing roller are a first photosensitive drum, a first storage chamber, and a second developing roller, respectively, the first cartridge has a first developing roller configured to carry a developer and supply the developer to the first photosensitive drum; the second cartridge has a second photosensitive drum configured to receive developer from the second developing roller; 6. The image forming apparatus according to any one of configurations 1 to 5. (Configuration 7) The second cartridge comprises: a holder that holds the sensor and is movable relative to the second frame; a biasing member that applies a biasing force to the holder to bias the holder toward the first frame; 7. The image forming apparatus according to any one of configurations 1 to 6, comprising: (Configuration 8) The image forming apparatus according to any one of configurations 1 to 7, wherein the sensor is positioned such that the less toner stored in the storage chamber, the longer the time it takes to detect the magnetism during rotation of the rotating shaft. (Configuration 9) The image forming apparatus according to any one of configurations 1 to 8, wherein the sensor is provided at a height that is higher than the bottom surface of the storage chamber and overlaps with the rotation shaft when viewed horizontally. (Configuration 10) 10. The image forming apparatus according to any one of configurations 1 to 9, wherein the sensor is provided so as to be aligned with the storage chamber in the first direction. (Configuration 11) When the accommodation chamber is a first accommodation chamber, the rotation shaft is a first rotation shaft, the rotation axis line is a first rotation axis line, the flexible member is a first flexible member, and the magnetic field generating member is a first magnetic field generating member, The second cartridge comprises: a second storage chamber for storing a developer; a second rotation shaft provided in the second storage chamber so as to be rotatable about a second rotation axis; a second flexible member having one end intersecting the second rotation axis as a free end and the other end fixed to the rotation axis, respectively; a second magnetic field generating member fixed between the fixed end and the free end of the second flexible member; and 11. The image forming apparatus according to any one of configurations 1 to 10, wherein the sensor is disposed at a position where it does not detect the magnetism generated by the second magnetism generating member. (Configuration 12) the first cartridge has a first frame body including the first storage chamber, the second cartridge has a second frame including the second storage chamber, In the alignment direction of the first cartridge and the second cartridge, the sensor is provided on the second frame on a side closer to the first frame, 12. The image forming apparatus according to any one of configurations 1 to 11, wherein the second storage chamber is provided on a side of the second frame that is farther from the first frame. (Configuration 13) the second cartridge has a photosensitive drum and a charging roller for charging the photosensitive drum, In the arrangement direction, The photosensitive drum and the charging roller are disposed on the side of the second frame that is closer to the first frame. It is established, The image forming apparatus according to any one of configurations 1 to 12, wherein the sensor is positioned higher than the charging roller and closer to the first frame than the photosensitive drum and the charging roller. (Configuration 14) the second cartridge has a photosensitive drum, a developing roller that carries developer for developing an electrostatic latent image formed on the photosensitive drum, a third storage chamber that stores developer to be supplied to the developing roller, and a cleaning member that removes the developer from the photosensitive drum; the second storage chamber is a storage chamber that stores the developer removed from the photosensitive drum by the cleaning member, In the arrangement direction, the third container and the developing roller are provided on a side of the second frame that is closer to the first frame, 14. The image forming apparatus according to any one of configurations 1 to 13, wherein the sensor is disposed at a position closer to the first frame than the third storage chamber and the developing roller. (Configuration 15) The first cartridge comprises: a first drum unit including a first photosensitive drum; a first developing unit including: a first developing roller that carries a developer for developing an electrostatic latent image formed on the first photosensitive drum; the first containing chamber that contains the developer to be supplied to the first developing roller; the first rotating shaft; the first flexible member; and the first magnetic generating member; and The second cartridge comprises: a second drum unit including a second photosensitive drum; a second developing unit including: a second developing roller that carries a developer for developing an electrostatic latent image formed on the second photosensitive drum; the second containing chamber that contains the developer to be supplied to the second developing roller; the second rotating shaft; the second flexible member; and the second magnetic generating member; and the first drum unit, the first developing unit, the second drum unit, and the second developing unit are arranged in this order; 15. The image forming apparatus according to any one of configurations 1 to 14, wherein the sensor is provided in the second drum unit. (Configuration 16) The image forming apparatus according to any one of configurations 1 to 15, wherein the second developing unit is configured to be movable relative to the second drum unit so that the second developing roller can be positioned in contact with the second photosensitive drum and in a spaced apart position. (Configuration 17) The first cartridge comprises: a first drum unit including a first photosensitive drum, a first cleaning member for removing developer from the first photosensitive drum, the first storage chamber for storing the developer removed from the first photosensitive drum by the first cleaning member, the first rotating shaft, the first flexible member, and the first magnetic field generating member; a first developing unit including a first developing roller that carries a developer for developing the electrostatic latent image formed on the first photosensitive drum; and The second cartridge comprises: a second drum unit including a second photosensitive drum, a second cleaning member for removing developer from the second photosensitive drum, the second storage chamber for storing the developer removed from the second photosensitive drum by the second cleaning member, the second rotating shaft, the second flexible member, and the second magnetic field generating member; a second developing unit including a second developing roller that carries a developer for developing the electrostatic latent image formed on the second photosensitive drum; and the first developing unit, the first drum unit, the second developing unit, and the second drum unit are arranged in this order; 17. The image forming apparatus according to any one of configurations 1 to 16, wherein the sensor is provided in the second developing unit. (Configuration 18) a third cartridge detachably attached to the main body of the apparatus, the third cartridge being attached to the main body of the apparatus adjacent to the second cartridge on the opposite side to the first cartridge, The sensor is a second sensor, 18. The image forming apparatus according to any one of configurations 1 to 17, wherein the third cartridge has a third sensor for detecting the magnetism generated by the second magnetism generating member. (Configuration 19) the apparatus main body has a tray that supports the first cartridge and the second cartridge, The sensor is a second sensor, 19. The image forming apparatus according to any one of configurations 1 to 18, wherein the tray has a fourth sensor for detecting the magnetism generated by the second magnetism generating member. (Configuration 20) a storage chamber for storing a developer; a rotation shaft provided in the accommodation chamber so as to be rotatable about a rotation axis; a flexible member having one end intersecting the rotation axis and the other end being a free end and a fixed end fixed to the rotation axis, respectively; a magnetic field generating member fixed between the fixed end and the free end of the flexible member; and One of a plurality of cartridges detachably mountable to a main body of an image forming apparatus, A cartridge characterized by having a sensor for detecting magnetism generated by another magnetism generating member provided in another cartridge among the plurality of cartridges attached to the apparatus main body. (Configuration 21) 21. The cartridge according to claim 20, wherein the sensor does not detect the magnetism generated by the magnetism generating member provided in the cartridge. (Configuration 22) aligned with the other cartridge in a first direction; 22. The cartridge of claim 20 or 21, wherein the sensor is disposed between the cartridge and the other cartridge in the first direction. (Configuration 23) A photosensitive drum; a frame that rotatably supports the photosensitive drum; and 23. The configuration according to any one of configurations 20 to 22, wherein the sensor is supported by a frame body of another cartridge so as to face the frame body of another cartridge in the first direction. The cartridge described in (Configuration 24) a holder that holds the sensor and is movable relative to the other frame; a biasing member that applies a biasing force to the holder to bias the holder toward the other frame body; The cartridge according to any one of Configurations 20 to 23, comprising: (Configuration 25) A cartridge described in any one of configurations 20 to 24, characterized in that the sensor is positioned so that the less toner is contained in the other storage chamber of the other cartridge, the longer the time it takes to detect the magnetic field generated by the other magnetic generating member during rotation of the other rotating shaft of the other cartridge. (Configuration 26) The image forming apparatus according to any one of configurations 20 to 25, characterized in that the sensor is located at a height that, when viewed horizontally, is higher than the bottom surface of another storage chamber provided in the other cartridge and overlaps with another rotation shaft provided in the other cartridge. (Configuration 27) The cartridge comprises: a drum unit including a photosensitive drum; a developing unit including: a developing roller that carries a developer for developing an electrostatic latent image formed on the photosensitive drum; an accommodation chamber that accommodates the developer to be supplied to the developing roller; the rotating shaft; the flexible member; and the magnetic field generating member; and The cartridge according to any one of Configurations 20 to 26, wherein the sensor is provided in the drum unit. (Configuration 28) The drum unit has a charging roller for charging the photosensitive drum, A cartridge described in any one of configurations 20 to 27, characterized in that the sensor is positioned higher than the charging roller and closer to the other cartridge than the photosensitive drum and the charging roller. (Configuration 29) The cartridge comprises: a drum unit including a photosensitive drum, a cleaning member for removing developer from the photosensitive drum, the storage chamber for storing the developer removed from the photosensitive drum by the cleaning member, the rotating shaft, the flexible member, and the magnetism generating member; a developing unit including a developing roller that carries a developer for developing the electrostatic latent image formed on the photosensitive drum; and The cartridge according to any one of Configurations 20 to 28, wherein the sensor is provided in the developing unit. (Configuration 30) the developing unit has a second storage chamber that stores developer to be supplied to the developing roller, 30. The cartridge according to any one of Configurations 20 to 29, wherein the sensor is disposed at a position closer to the other cartridge than the second storage chamber and the developing roller. (Configuration 31) The cartridge according to any one of Configurations 20 to 30, wherein the magnetism generated by the magnetism generating member is detected by another sensor provided in a still another cartridge that is attached to the apparatus main body. (Configuration 32) the cartridge is supported by a tray provided in the main body of the apparatus; 32. The cartridge according to any one of configurations 20 to 31, wherein the magnetism generated by the magnetism generating member is detected by another sensor provided in the tray. [Explanation of symbols]

[0104] 170... main body of the device, 100... cartridge, 116... toner storage chamber, 111... stirring shaft, 112... flexible sheet, 113... magnet, 114... magnetic sensor

Claims

1. An image forming apparatus, A device body, a first cartridge detachably mountable to the main body of the apparatus, the first cartridge including: a storage chamber for storing a developer; a rotation shaft provided in the storage chamber so as to be rotatable about a rotation axis; a flexible member having one end and the other end in a direction intersecting the rotation axis as a free end and a fixed end fixed to the rotation shaft, respectively; and a magnetic generating member fixed between the fixed end and the free end of the flexible member; a second cartridge detachably attachable to the apparatus main body, the second cartridge having a sensor for detecting the magnetism generated by the magnetic field generating member; An image forming apparatus comprising:

2. the first cartridge and the second cartridge are aligned in a first direction; 2. The image forming apparatus according to claim 1, wherein the sensor is provided between the first cartridge and the second cartridge in the first direction.

3. the first cartridge has a first frame that defines the storage chamber, and a developing roller that is configured to carry the developer in the storage chamber, the second cartridge has a photosensitive drum and a second frame that rotatably supports the photosensitive drum, 3. The image forming apparatus according to claim 2, wherein the sensor is supported by the second frame so as to face the first frame in the first direction.

4. When the photosensitive drum, the storage chamber, and the developing roller are respectively a second photosensitive drum, a first storage chamber, and a first developing roller, the first cartridge has a first photosensitive drum configured to receive developer from the first developing roller, The second cartridge has a second storage chamber that stores developer, and a second developing roller that carries the developer in the second storage chamber and is configured to supply the developer to the second photosensitive drum.

4. The image forming apparatus according to claim 3, wherein the image forming apparatus is a recording medium.

5. the first cartridge includes a photosensitive drum, a cleaning member that removes developer from the photosensitive drum, and a first frame that rotatably supports the photosensitive drum and also supports the cleaning member; the storage chamber is formed by the first frame and is a storage chamber that stores the developer removed from the photosensitive drum by the cleaning member, the second cartridge has a developing roller configured to carry a developer, and a second frame that rotatably supports the developing roller, 3. The image forming apparatus according to claim 2, wherein the sensor is supported by the second frame so as to face the first frame in the first direction.

6. When the photosensitive drum, the storage chamber, and the developing roller are respectively a first photosensitive drum, a first storage chamber, and a second developing roller, the first cartridge has a first developing roller configured to carry a developer and supply the developer to the first photosensitive drum; the second cartridge has a second photosensitive drum configured to receive developer from the second developing roller; 4. The image forming apparatus according to claim 3, wherein the image forming apparatus is a recording medium.

7. The second cartridge is a holder that holds the sensor and is movable relative to the second frame; a biasing member that applies a biasing force to the holder to bias the holder toward the first frame; 4. The image forming apparatus according to claim 3, further comprising:

8. 2. The image forming apparatus according to claim 1, wherein the sensor is disposed at a position where the less toner is contained in the containing chamber, the longer the time during which the sensor detects the magnetism during rotation of the rotary shaft.

9. 2. The image forming apparatus according to claim 1, wherein the sensor is provided at a height higher than a bottom surface of the storage chamber and overlaps with the rotation shaft when viewed horizontally.

10. 2. The image forming apparatus according to claim 1, wherein the sensor is provided so as to be aligned with the storage chamber in the first direction.

11. When the accommodation chamber is a first accommodation chamber, the rotation shaft is a first rotation shaft, the rotation axis line is a first rotation axis line, the flexible member is a first flexible member, and the magnetic field generating member is a first magnetic field generating member, The second cartridge is a second storage chamber for storing developer; a second rotation shaft provided in the second storage chamber so as to be rotatable about a second rotation axis; a second flexible member having one end intersecting the second rotation axis as a free end and the other end fixed to the rotation axis, respectively; a second magnetic field generating member fixed between the fixed end and the free end of the second flexible member; and 2. The image forming apparatus according to claim 1, wherein the sensor is disposed at a position where it does not detect the magnetic field generated by the second magnetic field generating member.

12. the first cartridge has a first frame including the first storage chamber, the second cartridge has a second frame including the second storage chamber, In the alignment direction of the first cartridge and the second cartridge, the sensor is provided on the second frame on a side closer to the first frame, 12. The image forming apparatus according to claim 11, wherein the second storage chamber is provided on a side of the second frame that is farther from the first frame.

13. the second cartridge has a photosensitive drum and a charging roller for charging the photosensitive drum, In the arrangement direction, the photosensitive drum and the charging roller are provided on the second frame on a side closer to the first frame, 13. The image forming apparatus according to claim 12, wherein the sensor is disposed at a position higher than the charging roller and closer to the first frame than the photosensitive drum and the charging roller.

14. The second cartridge includes a photosensitive drum, a developing roller that carries developer for developing an electrostatic latent image formed on the photosensitive drum, and a developer cartridge that stores the developer to be supplied to the developing roller. a third storage chamber for storing developer, and a cleaning member for removing developer from the photosensitive drum; the second storage chamber is a storage chamber that stores the developer removed from the photosensitive drum by the cleaning member, In the arrangement direction, the third storage chamber and the developing roller are provided on a side of the second frame that is closer to the first frame, 13. The image forming apparatus according to claim 12, wherein the sensor is disposed at a position closer to the first frame than the third container chamber and the developing roller.

15. The first cartridge comprises: a first drum unit including a first photosensitive drum; a first developing unit including: a first developing roller that carries a developer for developing an electrostatic latent image formed on the first photosensitive drum; a first storage chamber that stores the developer to be supplied to the first developing roller; the first rotating shaft; the first flexible member; and the first magnetic generating member; and The second cartridge is a second drum unit including a second photosensitive drum; a second developing unit including: a second developing roller that carries a developer for developing an electrostatic latent image formed on the second photosensitive drum; the second containing chamber that contains the developer to be supplied to the second developing roller; the second rotating shaft; the second flexible member; and the second magnetic generating member; and the first drum unit, the first developing unit, the second drum unit, and the second developing unit are arranged in this order; 12. The image forming apparatus according to claim 11, wherein the sensor is provided in the second drum unit.

16. 16. The image forming apparatus according to claim 15, wherein the second developing unit is configured to be movable relative to the second drum unit so that the second developing roller can be positioned between a contact position and a separation position with respect to the second photosensitive drum.

17. The first cartridge comprises: a first drum unit including a first photosensitive drum, a first cleaning member for removing developer from the first photosensitive drum, the first storage chamber for storing the developer removed from the first photosensitive drum by the first cleaning member, the first rotating shaft, the first flexible member, and the first magnetic field generating member; a first developing unit including a first developing roller that carries a developer for developing the electrostatic latent image formed on the first photosensitive drum; and The second cartridge is a second drum unit including a second photosensitive drum, a second cleaning member for removing developer from the second photosensitive drum, the second storage chamber for storing the developer removed from the second photosensitive drum by the second cleaning member, the second rotation shaft, the second flexible member, and the second magnetic field generating member; a second developing unit including a second developing roller that carries a developer for developing the electrostatic latent image formed on the second photosensitive drum; and the first developing unit, the first drum unit, the second developing unit, and The second drum unit is arranged in this order.

12. The image forming apparatus according to claim 11, wherein the sensor is provided in the second developing unit.

18. a third cartridge detachably attached to the apparatus main body, the third cartridge being attached to the apparatus main body adjacent to the second cartridge on the opposite side to the first cartridge, The sensor is a second sensor, 12. The image forming apparatus according to claim 11, wherein the third cartridge has a third sensor for detecting the magnetic field generated by the second magnetic field generating member.

19. the apparatus main body has a tray that supports the first cartridge and the second cartridge, The sensor is a second sensor, 12. The image forming apparatus according to claim 11, wherein the tray has a fourth sensor for detecting the magnetic field generated by the second magnetic field generating member.

20. a storage chamber for storing a developer; a rotation shaft provided in the accommodation chamber so as to be rotatable about a rotation axis; a flexible member having one end intersecting the rotation axis and the other end being a free end and a fixed end fixed to the rotation axis, respectively; a magnetic field generating member fixed between the fixed end and the free end of the flexible member; and One of a plurality of cartridges detachably mountable to a main body of an image forming apparatus, A cartridge characterized by having a sensor for detecting magnetism generated by another magnetism generating member provided in another cartridge among the plurality of cartridges attached to the apparatus main body.

21. 21. A cartridge according to claim 20, wherein the sensor does not detect the magnetism generated by the magnetism generating member provided in the cartridge.

22. aligned with the other cartridge in a first direction; The cartridge according to claim 20, wherein the sensor is provided between the cartridge and the other cartridge in the first direction.

23. A photosensitive drum; a frame that rotatably supports the photosensitive drum; and 21. The cartridge according to claim 20, wherein the sensor is supported by the frame so as to face another frame of the other cartridge in the first direction.

24. a holder that holds the sensor and is movable relative to the other frame; a biasing member that applies a biasing force to the holder to bias the holder toward the other frame body; 24. The cartridge of claim 23, comprising:

25. 3. The sensor is disposed at a position where the time for detecting the magnetic field generated by the magnetic field generating member during rotation of the rotary shaft of the cartridge increases as the amount of toner contained in the other container chamber of the cartridge decreases.

10. The cartridge according to claim 0.

26. 21. The image forming apparatus according to claim 20, wherein the sensor is located at a height that is higher than the bottom surface of another storage chamber of the other cartridge when viewed horizontally and overlaps with another rotation shaft of the other cartridge.

27. The cartridge comprises: a drum unit including a photosensitive drum; a developing unit including: a developing roller that carries a developer for developing an electrostatic latent image formed on the photosensitive drum; an accommodation chamber that accommodates the developer to be supplied to the developing roller; the rotating shaft; the flexible member; and the magnetic field generating member; and 21. A cartridge according to claim 20, wherein the sensor is provided in the drum unit.

28. The drum unit has a charging roller for charging the photosensitive drum, 28. The cartridge according to claim 27, wherein the sensor is disposed at a position higher than the charging roller and closer to the other cartridge than the photosensitive drum and the charging roller.

29. The cartridge comprises: a drum unit including a photosensitive drum, a cleaning member for removing developer from the photosensitive drum, the storage chamber for storing the developer removed from the photosensitive drum by the cleaning member, the rotating shaft, the flexible member, and the magnetism generating member; a developing unit including a developing roller that carries a developer for developing the electrostatic latent image formed on the photosensitive drum; and 21. A cartridge according to claim 20, wherein the sensor is provided in the developing unit.

30. the developing unit has a second storage chamber that stores developer to be supplied to the developing roller, 30. A cartridge according to claim 29, wherein the sensor is disposed at a position closer to the other cartridge than the second storage chamber and the developing roller.

31. 21. A cartridge according to claim 20, wherein the magnetism generated by said magnetism generating member is detected by another sensor provided in a still further cartridge that is mounted in the main body of the apparatus.

32. the cartridge is supported by a tray provided in the main body of the apparatus; 21. A cartridge according to claim 20, wherein the magnetism generated by said magnetism generating member is detected by another sensor provided in said tray.

Images