Image forming apparatus

Abstract

To provide a new form of an image forming apparatus employing a system of collectively supplying toner by using a toner container.SOLUTION: An image forming apparatus has a supply port 32a to which toner in a toner container is supplied, and an introduction port 32c provided in a frame body 32 so as to communicate with the supply port 32a. When seen in a rotation axis direction of a rotation shaft 34a of a stirring member 34, in a two-dimensional coordinate system formed by a first virtual line passing through the rotation axis and extending in a horizontal direction and a second virtual line passing through the rotation axis and extending in a gravity direction, at least part of the introduction port 32c is located in the first quadrant or the second quadrant. The control unit controls the stirring member 34 to stop its rotation in a state where at least part of a second end of a sheet 34b is located in the different quadrant from the quadrant in which the introduction port 32c is arranged in the coordinate system, by the timing at which the toner passes through the introduction port 32c when the toner is supplied from the toner container to a storage chamber 32d.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus for forming an image on a recording material. [Background technology]

[0002] In general, an electrophotographic image forming apparatus forms an image on a recording material by transferring a toner image formed on the surface of a photosensitive drum to the recording material. Known methods for replenishing a developer consumed in image formation include, for example, a process cartridge method and a toner replenishing method. In the process cartridge method, a photosensitive drum and a developing container are integrated as a process cartridge, and when the developer runs out, the process cartridge is replaced with a new one. On the other hand, in the toner replenishing method, when the toner runs out, new toner is replenished to the developing container without replacing components as in the process cartridge method. Patent Document 1 discloses a configuration of a toner replenishing method in which a toner pack is attached to the developing container so that a part of the toner container is exposed to the outside, and the toner contained in the toner pack is replenished in a lump into the developing container without replacing the process cartridge. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2022-27631 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a new embodiment of the toner supply type image forming apparatus disclosed in Patent Document 1. [Means for solving the problem]

[0005] In order to achieve the above object, an image forming apparatus according to the present invention comprises: An image forming apparatus to which a toner container can be attached, A photosensitive drum; a developing roller for supplying toner to the photosensitive drum; a mounting portion into which the toner container can be mounted so that a portion of the toner container is exposed to the outside of the image forming apparatus, the mounting portion being provided with a refill port through which toner is replenished in the toner container; a frame having a developing chamber in which the developing roller is disposed, and a storage chamber in which toner is stored and which is connected to the developing chamber and has a storage chamber opening that can communicate with the supply port; The stirring member is provided in the storage chamber, and includes a rotating shaft that rotates around a rotation axis, a first end that is one end in a direction perpendicular to the rotation axis, and a second end that is a sheet having a second end that is capable of contacting an inner wall of the toner storage chamber, the agitating member rotating to agitate the toner stored in the toner storage chamber; A control unit for controlling the rotation of the stirring member; Equipped with When viewed in the direction of the rotation axis, in a two-dimensional coordinate system formed by a first virtual line passing through the rotation axis and extending in a horizontal direction, and a second virtual line passing through the rotation axis and extending in a gravity direction, at least a portion of the storage chamber opening is disposed in a first quadrant or a second quadrant; The control unit is characterized in that, when toner is replenished from the toner container to the storage chamber, the control member controls the stirring member so that, by the time the toner passes through the storage chamber opening, at least a portion of the second end of the sheet stops rotating in a state where it is located in a quadrant in the coordinate system different from the quadrant in which the storage chamber opening is located. Effect of the Invention

[0006] According to the present invention, it is possible to provide a new embodiment of an image forming apparatus that uses a toner supply system in which toner is replenished all at once. [Brief description of the drawings]

[0007] [Figure 1] 1 is a cross-sectional view and a perspective view of an image forming apparatus 1 according to a first embodiment of the present invention; [Diagram 2] FIG. 3 is a perspective view of the stirring member 34. [Diagram 3] Image formation process flow chart [Figure 4] A perspective view and a front view of the process cartridge 20 and the toner pack 40 [Diagram 5] FIG. 13 shows the phase of the stirring member 34 during replenishment and the state of toner mixing by subsequent stirring. [Figure 6] FIG. 13 shows the phase of the stirring member 34 during replenishment and the state of toner mixing by subsequent stirring. [Figure 7] FIG. 13 shows another phase of the stirring member 34 during replenishment. [Figure 8] FIG. 13 shows another phase of the stirring member 34 during replenishment. [Figure 9] FIG. 13 is a diagram showing the phase of the stirring member 34 during replenishment in the second embodiment. [Figure 10] Cross-sectional view of a process cartridge according to a third embodiment [Figure 11] Cross-sectional view of a process cartridge according to a third embodiment [Figure 12] FIG. 13 shows a toner remaining amount sensor 50 according to a third embodiment. [Figure 13] FIG. 13 is a diagram showing the phase of the stirring member 34 and the toner mixing state during replenishment in the third embodiment. [Figure 14] FIG. 13 is a diagram showing the phase of the stirring member 34 and the toner mixing state during replenishment in the third embodiment. [Figure 15] FIG. 2 is a schematic plan view showing the optical path of a laser beam from an exposure unit; [Figure 16] Block diagram showing a control system of the image forming apparatus 1 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] In the following examples, the embodiments of the present disclosure will be described by way of example. However, the configurations disclosed in the following examples, such as the functions, materials, shapes, and relative positions of the parts, are examples of forms related to the scope of the claims, and are not intended to limit the scope of the claims to the configurations disclosed in these examples. Furthermore, the problems solved by the configurations disclosed in the following examples or the actions or effects obtained from the disclosed configurations are not intended to limit the scope of the claims.

[0009] Example 1 Fig. 1(a) is a schematic cross-sectional view showing the configuration of an image forming apparatus 1 according to a first embodiment of the present invention. Fig. 1(b) is a perspective view of the image forming apparatus 1 according to this embodiment. Fig. 2 is a schematic perspective view showing the configuration of an agitating member. The image forming apparatus 1 is a monochrome printer that forms an image on a recording material based on image information input from an external device.

[0010] 1(a) shows a state in which the image forming apparatus 1 is installed on a horizontal plane as a normally assumed installation state of the image forming apparatus 1, and the directions on the paper in this figure are defined as follows. The up and down directions on the paper are the vertical direction (the direction of gravity), the up direction on the paper is called the up direction, and the down direction on the paper is called the down direction. The left direction on the paper is called the back direction (the direction from the front side of the device to the back side), and the right direction on the paper is called the front direction (the direction from the back side of the device to the front side). Also, the front direction on the paper (the direction perpendicular to the paper, from the back side of the paper to the front side of the paper) is called the left direction, and the back direction (the direction perpendicular to the paper, from the front side of the paper to the back side of the paper) is called the right direction.

[0011] The image forming section 10 has a scanner unit 11, an electrophotographic process cartridge 20, and a transfer roller 12 that transfers a toner image formed on a photosensitive drum (image carrier) 21 of the process cartridge 20 onto a recording material.

[0012] The process cartridge 20 has a photosensitive drum 21, and a developing device 30 including a charging roller 22, a pre-exposure device 23, and a developing roller (developer carrier) 31, which are arranged around the photosensitive drum 21.

[0013] The photosensitive drum 21 is a cylindrically shaped photosensitive member. The photosensitive drum 21 of this embodiment has a photosensitive layer formed of a negatively charged organic photosensitive member on a drum-shaped base body formed of aluminum. The photosensitive drum 21 is rotated by a motor in a predetermined direction (clockwise direction in the figure) at a predetermined process speed.

[0014] The charging roller 22 comes into contact with the photosensitive drum 21 with a predetermined pressure to form a charging portion. A desired charging voltage is applied by a charging high-voltage power supply to uniformly charge the surface of the photosensitive drum 21 to a predetermined potential. In this embodiment, the photosensitive drum 21 is negatively charged by the charging roller 22. The pre-exposure device 23 neutralizes the surface potential of the photosensitive drum 21 before it enters the charging portion in order to generate a stable discharge in the charging portion.

[0015] The scanner unit (exposure means) 11 uses a polygon mirror to irradiate the photosensitive drum 21 with laser light corresponding to image information input from an external device, thereby scanning and exposing the surface of the photosensitive drum 21. This exposure forms an electrostatic latent image corresponding to the image information on the surface of the photosensitive drum 21. Note that the scanner unit 11 is not limited to a laser scanner device, and may be, for example, an LED exposure device having an LED array in which a plurality of LEDs are arranged along the longitudinal direction of the photosensitive drum 21.

[0016] The developing device 30 includes a developing container 32 (frame) in which a developer is contained, a developing roller 31 as a developer carrier that carries the developer, and a supply roller 33 capable of supplying the developer to the developing roller 31. The toner contained in the developing container 32 as the developer is applied to the surface of the developing roller 31 by the supply roller 33. The developing container 32 has a developing chamber 32e in which the developing roller 31 and the supply roller 33 are disposed, and a toner storage chamber (developer storage chamber) 32d that communicates with the developing chamber 32e and stores toner to be supplied to the developing chamber 32e. The developing container 32 has a convex portion (A in FIG. 1(a)) in the developing chamber 32e to hold the toner to be supplied to the developing roller 31 and the supply roller 33. The boundary portion between the toner storage chamber 32d and the developing chamber 32e at a position corresponding to the convex portion A is referred to as a developing opening 39. The supply roller 33 is not necessarily required as long as the supply roller 33 is configured to supply a sufficient amount of toner to the developing roller 31 .

[0017] The developing device 30 of this embodiment employs a contact developing method as a developing method, that is, the toner layer carried by the developing roller 31 comes into contact with the photosensitive drum 21 at a developing portion where the photosensitive drum 21 and the developing roller 31 face each other.

[0018] A developing voltage is applied to the developing roller 31 by a high-voltage developing power supply. Under the developing voltage, the toner carried by the developing roller 31 is transferred from the developing roller 31 to the surface of the photosensitive drum 21 in accordance with the potential distribution on the surface of the photosensitive drum 21, thereby developing the electrostatic latent image into a toner image. Note that in this embodiment, a reversal development method is adopted. That is, the toner image is formed by adhering to the surface area of ​​the photosensitive drum 21, which has been charged in the charging process and then exposed in the exposure process, where the charge amount has attenuated.

[0019] In this embodiment, toner having a particle size of about 6 μm and a normal negative charge polarity is used. As an example of the toner used in this embodiment, a polymerized toner produced by a polymerization method is used. The toner in this embodiment does not contain a magnetic component, and is a so-called non-magnetic one-component developer in which the toner is carried on the developing roller 31 mainly by intermolecular forces and electrostatic forces (image forces). However, one-component developers containing magnetic components may also be used. One-component developers contain toner particles In addition, additives (e.g., wax and silica fine particles) may be included to adjust the fluidity and charging performance of the toner. A two-component developer consisting of a non-magnetic toner and a magnetic carrier may also be used as the developer. When a magnetic developer is used, a cylindrical developing sleeve with a magnet arranged inside is used as the developer carrier.

[0020] The developing blade 35 regulates the amount of toner carried by the developing roller 31. The toner supplied to the surface of the developing roller 31 passes through the portion facing the developing blade 35 as the developing roller 31 rotates, whereby the toner is uniformly formed into a thin layer and is negatively charged by frictional charging.

[0021] Further, an agitating member 34 is provided inside the toner storage chamber 32d of the developing container 32. As shown in FIG. 2, the agitating member 34 has an agitating shaft (rotating shaft) 34a extending in the longitudinal direction and a blade portion (sheet) 34b extending radially outward from the agitating shaft 34a. The blade portion 34b is attached to the agitating shaft 34a so that a mounting portion 34b11, which is a part of the blade portion 34b, contacts a mounting surface 34a1 of the agitating shaft 34a extending in the direction of the rotation axis of the agitating shaft 34a. The blade portion 34b is configured such that a first end 34be1, which is one end in a direction perpendicular to the rotation axis, is fixed to the agitating shaft 34a as a part of the mounting portion 34b11, and a second end 34be2, which is the other end, can contact the inner wall of the toner storage chamber 32d. The agitating member 34 is rotated about the agitating shaft 34a by a motor drive via a gear 34c.

[0022] The blade portion 34b of the stirring member 34 in this embodiment is made of polycarbonate with a thickness of 180 μm and is flexible. It stirs the toner in the developing container 32 while bending and returning to its original shape following the shape of the inner wall of the developing container 32. Furthermore, the longitudinal width W of the blade portion 34b of the stirring member 34 is set narrower than the longitudinal width of the developing opening 39, so that it can enter the developing opening 39. The blade portion 34b also plays a role in sending the toner through the developing opening 39 toward the developing chamber 32e in which the developing roller 31 and the supply roller 33 are located.

[0023] In this embodiment, the gear 34c of the stirring member 34 has a pin 34d disposed at a position corresponding to the blade portion 34b of the stirring member 34. FIG. 2 shows a state in which the gear 34c is removed from the stirring member 34. The phase detection sensor 51 is a reflective photointerrupter, and the control unit of the image forming apparatus 1 can determine the phase of the stirring member 34 by detecting the presence or absence of the pin 34d. That is, the phase detection sensor 51 has a light emitting unit (light emitting element) and a light receiving unit (light receiving element), and is configured to be able to grasp the position (phase) of the pin 34d by the detection light emitted from the light emitting unit being reflected by the pin 34d and received by the light receiving unit. The configuration of the phase detection sensor 51 is not limited to the reflective type, and a transmission type sensor may be used.

[0024] (Image formation operation) The image forming operation of the image forming apparatus 1 will be described with reference to Figures 1(a), 1(b) and 3. Figure 3 is a flowchart of the image forming process.

[0025] 3, a print job is started when a command is input to the image forming apparatus 1. An image forming process P2 is executed by the image forming unit 10 based on image information input from an external computer or the like connected to the image forming apparatus 1. Generally, a pre-rotation process P1 as a preparation process for image formation and a post-rotation process P3 as a post-treatment process are provided before and after the image forming process P2.

[0026] In the pre-rotation process P1, the scanner unit 11, various high voltage power supplies, and the fixing unit 70 are started and stabilized. When each unit has started up, that is, when each unit is ready or expected to be ready to form an image, the pre-rotation process P1 is terminated and image formation is started. The generation process P2 is then started.

[0027] In the image formation process P2, the scanner unit 11 irradiates the photosensitive drum 21 with laser light L (see FIG. 1(a)) based on the input image information. At this time, the photosensitive drum 21 is pre-charged by the charging roller 22, and an electrostatic latent image is formed on the photosensitive drum 21 by irradiating it with the laser light L. Thereafter, the electrostatic latent image is developed by the developing roller 31, and a toner image is formed on the photosensitive drum 21.

[0028] In parallel with this image forming process, the feeding section 60 conveys the recording material P toward a transfer nip formed by the transfer roller 12 and the photosensitive drum 21. A transfer voltage is applied to the transfer roller 12 from a transfer high voltage power supply, and the toner image carried on the photosensitive drum 21 is transferred onto the recording material P.

[0029] The recording material P onto which the toner image has been transferred is conveyed to the fixing unit 70, and the toner image is heated and pressurized when passing through a nip between a fixing film 71 and a pressure roller 72 of the fixing unit 70. This causes the toner particles to melt and then adhere to the recording material P, thereby fixing the toner image to the recording material P.

[0030] The recording material P that has passed through the fixing unit 70 is discharged to the outside of the image forming apparatus 1 (outside the machine) by a pair of discharge rollers 80 serving as a discharge means, and is stacked on a discharge tray 81 serving as a stacking unit formed on the upper part of the image forming apparatus 1. After all the designated recording materials have been discharged onto the discharge tray 81, the image forming apparatus 1 proceeds to a post-rotation process P3.

[0031] In the post-rotation process P3, various high-voltage power supplies are turned off, and the fixing unit 70 is rotated at a temperature lower than the temperature control during paper passage or with the temperature control turned off in order to equalize the temperature difference between the paper passing area and the non-paper passing area.

[0032] In this embodiment, after the post-rotation process P3, a phase determination process P4 is performed to determine the phase of the blade portion 34b of the agitating member 34 disposed in the developing container 32 in preparation for toner replenishment. After the phase determination process P4, a phase adjustment process P5 is performed to stop the motor drive at a timing when the position of the blade portion 34b of the agitating member 34 reaches a predetermined position, and the image forming operation is terminated. The configuration related to toner replenishment, the phase determination process P4, and the phase adjustment process P5 will be described in detail later.

[0033] (Cleanerless toner collection) The toner (transfer residual toner) remaining on the photosensitive drum 21 without being transferred to the recording material P during the transfer step is removed from the photosensitive drum 21 in the following manner.

[0034] After the transfer process, the surface of the photosensitive drum 21 is neutralized by a pre-exposure device 23 so that the surface potential becomes 0 V, and then the photosensitive drum 21 enters a charging section. The residual toner remaining on the photosensitive drum 21 includes a mixture of positively charged toner and negatively charged toner that does not have a sufficient charge. This residual toner is charged negatively by discharge in the charging section.

[0035] The transfer residual toner, which has been negatively charged in the charging section, reaches a position facing the developing roller 31 as the photosensitive drum 21 rotates. Here, an electrostatic latent image corresponding to image information is formed on the surface of the photosensitive drum 21 that has reached the position facing the developing roller 31. The transfer residual toner adhering to the non-exposed portion (non-image portion) of the photosensitive drum 21 moves from the photosensitive drum 21 to the developing roller 31 due to the potential difference between the pre-exposure potential on the photosensitive drum 21 and the development voltage at the portion facing the developing roller 31, and is then collected in the developing chamber 32e of the developing container 32. The toner collected in 2e is reused for image formation.

[0036] On the other hand, the residual toner adhering to the exposed portion (image portion) on the photosensitive drum 21 does not move from the photosensitive drum 21 to the developing roller 31, but forms a toner image together with the toner that has moved from the developing roller 31 to the photosensitive drum 21. Then, this toner is transferred onto the recording material P at the transfer portion and removed from the photosensitive drum 21.

[0037] (Control system of image forming device) 16 is a block diagram showing a control system of the image forming apparatus 1. A control unit 90 as a control means of the image forming apparatus 1 has a CPU 91 as a calculation device, a RAM 92 used as a work area for the CPU 91, and a ROM 93 for storing various programs. The control unit 90 also has an I / O interface 94 as an input / output port connected to an external device, and an A / D conversion unit 95 for converting an analog signal into a digital signal.

[0038] The input side of the control unit 90 is connected to a phase detection sensor 51, a mounting sensor 53, and an opening / closing sensor .

[0039] The phase detection sensor 51 detects the phase of the stirring member 34, and as described above, in this embodiment, is composed of a reflective photointerrupter. The mounting sensor 53 detects that the toner pack 40 is mounted in the supply port (developer receiving port) 32a of the developing container 32. For example, the mounting sensor 53 is provided in the supply port 32a and is composed of a pressure-sensitive switch that outputs a detection signal when pressed by the toner pack 40. The opening / closing sensor 54 detects the open / close state of the opening / closing member 83, that is, whether the opening / closing member 83 is opened relative to the discharge tray 81. The opening / closing sensor 54 is composed of, for example, a pressure-sensitive switch or a magnetic sensor.

[0040] The control unit 90 is also connected to an operation unit 300 and the image forming unit 10. The operation unit 300 has a display unit 301 capable of displaying various setting screens, physical keys, and the like. The display unit 301 is, for example, a liquid crystal panel. The image forming unit 10 has a motor M1 as a drive source for driving the photosensitive drum 21, the developing roller 31, the supply roller 33, the stirring member 34, and the like. The photosensitive drum 21, the developing roller 31, the supply roller 33, and the stirring member 34 may be configured to be driven by separate motors, respectively.

[0041] (Configuration related to toner supply) As shown in FIG. 1B, in this embodiment, which is a toner supply type, an opening / closing member 83 for supplying toner by a toner pack 40 (developer supply container) is provided in an openable / closable manner on a discharge tray 81. A main body side supply opening 82 that opens upward is formed on the discharge tray 81. The opening / closing member 83 is configured to be movable between a closed position that covers the supply port 32a (developer receiving port) so that the toner pack 40 cannot be attached to the developing container 32, and an open position that exposes the supply port 32a so that the toner pack 40 can be attached to the developing container 32. The opening / closing member 83 functions as a part of the discharge tray 81 in the closed position. The opening / closing member 83 and the main body side supply opening 82 are formed on the left side of the discharge tray 81.

[0042] The configurations of the developing container 32 and the toner pack 40 will be described with reference to Figures 4(a) and 4(b). Figure 4(a) is a perspective view showing the developing container 32 and the toner pack 40, and Figure 4(b) is a front view showing the developing container 32 and the toner pack 40.

[0043] The developing container 32 has a protruding portion 38 that protrudes upward from one end in the longitudinal direction of the device. An attachment portion 57 to which the toner pack 40 can be attached is provided at the upper end (tip) of the protruding portion 38. The attachment portion 57 is provided with a developer container 32 for transferring the developer from the toner pack 40 into the developing container 32. A supply port 32a is formed for supplying the agent. The supply port 32a opens to the outside of the developing container 32 and communicates with an introduction port 32c (accommodation chamber opening) that opens on the inner wall of the toner storage chamber 32d of the developing container 32. That is, a toner supply path extending from the supply port 32a to the introduction port 32c is formed inside the protruding portion 38, and the supply port 32a and the introduction port 32c are configured to be able to communicate with each other. That is, in this embodiment, the mounting portion 57 having the supply port 32a is disposed on the front side of the image forming apparatus 1, which makes it easy for the user to supply toner to the developing container 32.

[0044] The toner pack 40 is configured to be detachably attached to a mounting portion 57 provided at the tip of the protruding portion 38 of the developing container 32. The toner pack 40 also has an openable and closable shutter member 41 provided at the opening, and a plurality of protrusions 42 formed in correspondence with the plurality of grooves 32b formed in the mounting portion 57. The shutter member 41 is configured to be movable between an open position that opens the opening, and a closed position that closes the opening.

[0045] When replenishing toner in the developing container 32, the user aligns the projection 42 of the toner pack 40 so that it passes through the groove 32b of the mounting portion 57, and connects the toner pack 40 to the mounting portion 57. When the toner pack 40 is rotated 180 degrees in this state, the shutter member 41 of the toner pack 40 abuts against an abutment portion (not shown) of the mounting portion 57, causing the toner pack 40 to rotate relative to the main body of the toner pack 40 and opening the shutter member 41. This causes the toner contained in the toner pack 40 to leak out of the toner pack 40, and the leaked toner enters the developing container 32 through the replenishing port 32a. The shutter member 41 may be provided on the replenishing port 32a side.

[0046] The toner supplied from the supply port 32a is sent toward the developing roller 31 and the supply roller 33 as the stirring member 34 inside the developing container 32 rotates. The supply port 32a and the protruding portion 38 are disposed at one end of the developing container 32 in the longitudinal direction, but the toner is distributed throughout the entire developing container 32 as the stirring member 34 rotates repeatedly.

[0047] The positional relationship between the toner supply path of the developing container 32 and the scanner unit 11 will be described with reference to Fig. 15. Fig. 15 is a schematic plan view illustrating the positional relationship between the scanner unit 11 and the supply port 32a and the introduction port 32c of the developing container 32, and is a plan view along the scanning optical path of the laser light L of the scanner unit 11.

[0048] The scanner unit 11 includes a light source 110, an aperture 111, an incident optical element 112, a deflector 113, and an imaging optical element 114. The light source 110 is, for example, a semiconductor laser. The aperture 111 has an elliptical opening and limits the diameter of the light beam emitted from the light source 110 in each of the main scanning direction and the sub-scanning direction. The incident optical element 112 has a positive refractive power in the main scanning cross section, and converts the light beam that has passed through the aperture 111 into a parallel light beam in the main scanning cross section. In the scanner unit 11, the light beam that has passed through the aperture 111 is converted into a weakly convergent light beam, thereby reducing the refractive power required for the imaging optical element 114. The incident optical element 112 also has a positive refractive power in the sub-scanning cross section, and forms a long line image in the main scanning direction by concentrating the light beam that has passed through the aperture 111 near the deflection surface 113a of the deflector 113 in the sub-scanning cross section.

[0049] The imaging optical element 114 has positive refractive power in both the main scanning section and the sub-scanning section, and collects the light beam deflected by the deflector 113 in both the main scanning section and the sub-scanning section to form a spot-shaped image in the vicinity of the scanned surface of the photosensitive drum 21. Specifically, the imaging optical element 114 has two optical surfaces (lens surfaces), an entrance surface and an exit surface, and is configured so that the light beam deflected by the deflection surface 113a of the deflector 113 scans the scanned surface of the photosensitive drum 21 with desired scanning characteristics in the main scanning section. In addition, the imaging optical element 114 compensates for surface tilt (i.e., reduces the deviation of the scanning position in the sub-scanning direction on the scanned surface of the photosensitive drum 21 when the deflection surface 113a is tilted) by making the vicinity of the deflection surface 113a of the deflector 113 and the vicinity of the scanned surface of the photosensitive drum 21 in a conjugate relationship with each other in the sub-scanning cross section.

[0050] In this way, the light beam emitted from the light source 110 passes through the diaphragm 111 and the incident optical element 112, and then enters the deflection surface 113a of the deflector 113. Then, the light beam reflected and deflected by the deflection surface 113a of the deflector 113 is guided to the scanned surface of the photosensitive drum 21 by the imaging optical element 114. The deflector 113 is rotated at a constant speed by a driving unit (not shown), and optically scans the scanned surface of the photosensitive drum 21 in the main scanning direction indicated by the arrow D, thereby forming an electrostatic latent image on the scanned surface of the photosensitive drum 21.

[0051] 15 and 1(a), the protrusion 38 of the developing container 32 (the toner supply path from the supply port 32a to the introduction port 32c) extends above and below the scanning optical path of the laser light L of the scanner unit 11 at a position that avoids the scanning optical path of the laser light L. That is, when viewed in the left-right direction of the device, the supply port 32a is located above the scanning optical path of the laser light L, and the introduction port 32c is located below the scanning optical path of the laser light L. The left-right direction of the device is a direction approximately parallel to the rotation axis direction of rotating bodies such as the photosensitive drum 21, the developing roller 31, the supply roller 33, and the stirring member 34.

[0052] 15, the toner supply path from the supply port 32a to the introduction port 32c is located inside the end of the photosensitive drum 21 (toward the center of the photosensitive drum 21) in the left-right direction of the device. Also, it is located between the photosensitive drum 21 and the scanner unit 11 in the front-rear direction of the device. In other words, the protrusion 38 of the developing container 32 is disposed so as to avoid the scanning optical path of the laser light L emitted from the imaging optical element 114, and not to increase the size of the device in the left-right direction and the front-rear direction of the device.

[0053] (Phase of blade portion 34b and mixture state of new and old toner during replenishment) The toner (hereinafter referred to as new toner) supplied from the supply port 32a by the toner pack 40 is introduced into the toner storage chamber 32d through the introduction port 32c, and is distributed throughout the entire longitudinal area of ​​the toner storage chamber 32d by the rotation of the stirring member 34 in the toner storage chamber 32d. The new toner is gradually mixed with the toner (hereinafter referred to as old toner) that was originally present in the developing container 32.

[0054] Here, it was found that the degree to which new toner enters the toner storage chamber 32d differs depending on the stop phase of the blade portion 34b of the stirring member 34 before the start of rotation when new toner is replenished. Specifically, it was found that there are cases in which the new toner instantly spreads over the entire longitudinal area of ​​the toner storage chamber 32d and enters, and cases in which the new toner remains in the longitudinal area of ​​the toner storage chamber 32d near the inlet 32c. It was also found that in each case, the time required for the new toner and the old toner to be uniformly mixed by the rotation of the stirring member 34 after the new toner is replenished by the toner pack 40 differs greatly.

[0055] 5(a) to 6(d) are schematic diagrams showing the state of new toner (hatched area) supplied from the toner pack 40 and old toner (filled area) in the developing container 32. FIG. 5(a) and FIG. 6(a) are schematic cross-sectional views of the developing container 32 as viewed from the side (left side). FIG. 5(b) to FIG. 5(d) and FIG. 6(b) to FIG. 6(d) are schematic diagrams showing the inside of the developing container 32 as viewed from the front side. FIG. 5(a) to FIG. 6(d) are diagrams showing how the new toner actually mixes with the old toner when a transparent developing container 32 is prepared and yellow toner is used as the new toner in the toner pack 40 and black toner is used as the old toner in the transparent developing container 32. FIG. 5(b) to FIG. 5(d) and FIG. 6(b) to FIG. 6(d) show the state seen from the front side in the range including the stirring shaft 34a of the stirring member 34.

[0056] "Immediately after replenishment" here means before the agitating member 34 starts to rotate. The image diagrams viewed from the front also show the state immediately after replenishment, 10 seconds after the agitating member 34 starts to rotate (after 10 rotations of the agitating member 34), and 30 seconds after (after 30 rotations of the agitating member 34). The solid areas indicate areas where the proportion of old toner is high, the shaded areas indicate areas where the proportion of new toner is high, and the dotted areas indicate areas where the new toner and old toner are well mixed together.

[0057] Figures 5(a) to 5(d) show the case where new toner is supplied when the tip position of blade portion 34b of agitating member 34 at the time of supply is located farthest from inlet 32c. Figures 6(a) to 6(d) show the case where new toner is supplied when the tip position of blade portion 34b of agitating member 34 at the time of supply is located on the inlet 32c side.

[0058] Here, the position farthest from the inlet 32c is defined as follows. The inlet 32c is located in the first quadrant of a two-dimensional Cartesian coordinate system that is divided by an axis (second virtual line) in the direction of gravity and an axis (first virtual line) in the direction perpendicular to the direction of gravity (horizontal direction) with the rotation axis (center of rotation) of the stirring shaft 34a of the stirring member 34 as the center. With respect to the inlet 32c located in the first quadrant as one quadrant, the developing unit such as the photosensitive drum 21 and the developing roller 31 is located in the second quadrant as the other quadrant. In this case, the state in which the tip of the blade portion 34b of the stirring member 34 before replenishment is located in the third quadrant is defined as the position farthest from the inlet 32c. On the other hand, when the tip position of the blade portion 34b of the stirring member 34 during replenishment is located on the inlet 32c side, it means that the tip of the blade portion 34b of the stirring member 34 before replenishment is located in the same first quadrant as the inlet 32c.

[0059] In addition, the positional relationship of each component of the device using the above coordinate system does not require the device layout to strictly arrange each component in each quadrant. That is, the inlet 32c may be arranged so that a part of it (a large part of the inlet 32c) is included in the first quadrant and the other part protrudes into the other quadrants. Similarly, the blade portion 34b of the stirring member 34 may be arranged so that at least a part of the blade portion 34b including the tip (second end portion 34be2) of the blade portion 34b is included in the third quadrant and the other part protrudes into the other quadrants. Other positional relationships using the above coordinate system described below may be considered in the same manner.

[0060] As shown in Figures 5(a) to 5(d), when the tip of the blade portion 34b is located at the farthest position from the inlet 32c during the supply of new toner, the new toner is discharged into a sufficiently wide space. Then, as the new toner falls to the bottom surface of the developing container 32, it spreads out in the longitudinal direction as if it were collapsing into a mountain. In other words, the supplied new toner is distributed throughout the longitudinal direction. This is because the old toner in the developing container 32 is pushed toward the developing opening 39, so there is almost no old toner on the bottom surface of the developing container 32, and a wide space is seen from the inlet 32c.

[0061] However, on the other hand, as shown in FIG. 6(a) to FIG. 6(d), when the tip position of the vane portion 34b is located on the inlet 32c side during the supply of new toner, the new toner stays directly below the inlet 32a in the toner supply path from the inlet 32a inside the protruding portion 38 to the inlet 32c. The reasons for this state are considered to be as follows. One is that the vane portion 34b at this time is in a state before the old toner is sent toward the development opening 39 where the development roller 31 and the supply roller 33 are located, and the bottom of the development container 32 is filled with old toner. Another is that the vane portion 34b blocks the discharge space of the new toner. As a result, the new toner is discharged all at once into a narrow space, and the new toner accumulates in the protruding portion 38 as described above. The more the powder toner is discharged into a narrow space, the more it becomes clogged due to the pressure of the toner itself and the friction with each side surface. Therefore, the new toner is less likely to spread longitudinally inside the development container 32.

[0062] The purpose of this embodiment is to achieve, in a short time, a state in which new toner and old toner are mixed nearly uniformly in the longitudinal direction inside the developing container 32. The blade portion 34b agitates the toner in the rotational direction, but as it continues to rotate, the toner gradually mixes in the longitudinal direction as well.

[0063] As shown in Figures 6(a) to 6(d), when new toner remains in the vicinity of the inlet 32c in the longitudinal direction inside the developing container 32, even if the stirring member 34 is driven, it takes more than 30 seconds (30 rotations of the stirring member 34) for the new toner to spread throughout the entire longitudinal area.

[0064] However, as shown in Figures 5(a) to 5(d), since the tip of the blade portion 34b is located farthest from the inlet 32c, when the new toner spreads longitudinally inside the developing container 32 immediately after replenishment, it can be made uniform in about 10 seconds (10 rotations of the stirring member 34).

[0065] (Mixing old and new toner and image defects) If the image forming process is started without the old toner and the new toner being completely mixed, a poor image may occur due to poor transfer. The toner may be continuously stirred in the developing container 32, or, especially in the case of a cleanerless configuration as in this embodiment, the toner may become deformed or additives may be embedded in the toner due to repeated image forming processes. Therefore, the charging performance of the old toner may be lower than that of the new toner.

[0066] The higher the charging performance of the toner, the more easily it conforms to the potential distribution of the developing roller 31 and the photosensitive drum 21, and the more easily it is developed as a toner image into the electrostatic latent image on the photosensitive drum 21. Therefore, when old toner and new toner are mixed uniformly, the new toner in the mixed toner is preferentially used for image formation. However, if the toner is not mixed uniformly, a situation may arise in which new toner with high charging performance is used for image formation, or old toner with low charging performance is used for image formation.

[0067] Furthermore, the higher the charging performance of the toner, the stronger the bias required to transfer the toner image on the photosensitive drum 21 to the recording material P. On the other hand, if a high transfer bias is applied to a toner with low charging performance, a grainy image defect called strong dropout occurs. In other words, if the transfer bias is set to match the new toner with high charging performance, if there is an area where the old toner with low charging performance is used for image formation, a strong dropout image defect occurs. Therefore, if the mixture of the old toner and the new toner is not uniform, or if there is an area where only the old toner is present without the new toner being distributed in the longitudinal direction, strong dropout may occur in the area where the old toner was used for image formation.

[0068] In this way, the mixed state of the new and old toner varies after replenishment, making it difficult to set the transfer bias required after replenishment, and there are cases where transfer failures in the longitudinal direction are unavoidable. Therefore, it is desirable for the mixed state of the new and old toner to be such that the new toner is distributed as evenly as possible in the longitudinal direction.

[0069] (Phase determination process P4 and phase adjustment process P5) Therefore, in this embodiment, when the controller 90 supplies toner from the toner pack 40 to the developing container 32, the controller 90 controls the agitator 34 so that the agitator 34 stops rotating at a predetermined rotation phase at the latest by the time when the toner passes through the inlet 32c of the developing container 32. In other words, the controller 90 controls the rotation of the agitator shaft 34a so that the tip (second end 34be2) of the blade portion 34b stops rotating in a state where it is located in a quadrant different from the quadrant where the inlet 32c is located in the above coordinate system. More specifically, when the motor stops after a print job, The motor drive time is adjusted so that the phase of the blade portion 34b of the stirring member 34 is located at the farthest position from the inlet 32c when the motor is stopped. After the post-rotation process P3 following the image formation process P2, a phase determination process P4 and a phase adjustment process P5 are added to end the print job.

[0070] In this embodiment, in the phase determination process P4, the phase of the blade portion 34b of the agitating member 34 is determined by the pin 34d provided on the gear 34c of the agitating member 34 and the sensor 51. After the phase determination, the process proceeds to the phase adjustment process P5. In the phase adjustment process P5, the position of the blade portion 34b of the agitating member 34 is adjusted so that the blade portion 34b is positioned at the farthest position from the desired supply port 32a. The control unit is instructed to stop the motor. Depending on the motor, there may be several msec of inertia between the time the control unit is instructed to stop and the time the motor drive is actually turned off. In the image forming apparatus of this embodiment, a brush motor is used as the motor as the drive source, and even if the current is stopped, it takes time for the motor to completely stop rotating due to inertia. Therefore, it is desirable to adjust the stop instruction timing taking inertia into consideration.

[0071] Moreover, the blade portion 34b is deformed to some extent when it comes into contact with the inner wall of the toner storage chamber 32d. The degree of the deformation may change as the phase of the agitation shaft 34a changes. That is, the shape of the inner wall surface of the toner storage chamber 32d is not uniform with respect to the rotation center of the agitation shaft 34a, and when the contact position of the blade portion 34b with the inner wall surface of the toner storage chamber 32d changes, the magnitude of the reaction force that the tip of the blade portion 34b receives from the inner wall surface of the toner storage chamber 32d also changes, and the degree of deformation may also change. The shape of the inner wall of the toner storage chamber 32d is not a cylindrical surface centered on the rotation center of the agitation member 34, and the position change of the tip of the blade portion 34b during the rotation of the agitation member 34 is not constant with respect to the phase change of the agitation shaft 34a due to the change in the degree of deformation of the blade portion 34b. That is, it is considered that the position of the rotation phase of the agitation shaft 34a and the tip position of the blade portion 34b do not necessarily correspond one-to-one. It is considered that the deformation of the blade portion 34b may change depending on the amount of toner remaining in the toner storage chamber 32d. Therefore, it is preferable to grasp the correspondence between the rotation phase of the agitator shaft 34a and the tip position of the blade portion 34b in advance by experiments or the like, and to reflect this in the control amount of the rotation control of the agitator shaft 34a.

[0072] (Effects of this embodiment) According to this embodiment, when the motor is stopped after a print job is completed, the tip of the blade portion 34b can always be positioned at the farthest position from the inlet 32c in preparation for replenishment. At this time, the old toner in the developer container 32 is pushed toward the developer opening 39, creating a space on the bottom surface of the developer container 32. Due to this space, the new toner in the toner pack is discharged while spreading over the entire length of the developer container 32 without clogging. After this, when the agitator 34 starts rotating, the mixture of the new toner and the old toner is made uniform in a shorter time than in the conventional configuration (a configuration in which the phase control of the agitator 34 is not performed).

[0073] As described above, by making the new toner uniformly present over the entire longitudinal area of ​​the developing container 32 in a shorter time than before, the possibility of image defects occurring can be further reduced.

[0074] In this embodiment, the motor is stopped by the phase adjustment process so that the tip of the blade portion 34b is located in the third quadrant of an orthogonal coordinate system centered on the rotation center of the stirring shaft 34a of the stirring member 34, but this is not limited to the above. In this embodiment, the space into which new toner of the toner pack 40 is discharged is widest when the tip of the blade portion 34b of the stirring member 34 is stopped in the third quadrant. However, for example, as shown in Figures 7(a) to 8(d), even if the tip is stopped in the second or fourth quadrant, the same effect as described above can be achieved if the new toner of the toner pack 40 is discharged into a sufficiently wide space and enters the developing container 32 while spreading in the longitudinal direction.

[0075] In addition, in this embodiment, phase determination and phase adjustment are performed after the post-rotation process P3, but the time required for the entire process of the print job can be shortened by performing position determination in parallel with the post-rotation process P3.

[0076] Also, the phase adjustment may be performed in time for toner replenishment, and may be configured to be performed when the user actually replenishes toner. That is, for example, an opening / closing sensor 54 may be provided as a configuration capable of detecting the opening / closing of an opening / closing member 83 provided on the top cover, and when it is detected that the opening / closing member 83 is open, a motor may be driven to perform the phase determination process P4 and the phase adjustment process P5. Alternatively, a mounting sensor 53 may be provided as a configuration capable of detecting the mounting of the toner pack 40 in the mounting section 57, and when it is detected that the toner pack 40 is mounted in the mounting section 57, a motor may be driven to perform the phase determination process P4 and the phase adjustment process P5. That is, a configuration may be provided that is capable of detecting that the user is preparing to replenish toner (high probability of this), and a configuration may be configured to start the phase adjustment of the stirring member 34 by using the detection that the user has started to prepare for toner replenishment as a trigger.

[0077] In addition, the slower the motor drive speed (process speed) for position adjustment, the less the influence of inertia in the position adjustment. Therefore, the process speed in the phase determination process or phase adjustment process may be slower than the process speed in the image formation process. This makes it possible to perform position adjustment with high accuracy.

[0078] (others) The positional relationship of each component in the coordinate system shown in Figures 5(a) to 8(d) (the quadrant in which each component is located) is the positional relationship when the image forming apparatus is viewed from left to right. Therefore, conversely, the quadrant in which each component is located when viewed from right to left is reversed in the left-right direction of the paper. That is, for example, in the positional relationship of each component when viewed from right to left, the quadrant in which the introduction port 32c is located is the second quadrant, and the quadrant in which the tip of the blade portion 34b is stopped is the fourth quadrant, or the first or second quadrant.

[0079] Another possible reason why it takes time for new toner to mix with old toner is the relationship between the size of the toner storage chamber 32d of the developing container 32 and the size of the toner path of the protruding portion 38 (the size of the inlet 32c that opens into the inner wall surface of the toner storage chamber 32d). This problem is likely to occur when the width of the protruding portion 38 (inlet 32c) is small compared to the overall longitudinal length of the toner storage chamber 32d.

[0080] In this embodiment, in consideration of usability, the toner can be replenished from the top of the device, and the replenishment port does not block the laser light for exposure, and the inlet 32c is opened at a position offset toward one longitudinal end of the toner storage chamber 32d, as described above. In this embodiment, the longitudinal length of the toner storage chamber 32d is 230 mm, the longitudinal width (inner diameter) of the inlet 32c is 40 mm, and the length from the longitudinal center of the toner storage chamber 32d to the width center of the inlet 32c is 86 mm. Regarding the longitudinal position of the inlet 32c relative to the toner storage chamber 32d, even if the inlet 32c is opened at the longitudinal center of the toner storage chamber 32d, there is a concern that new toner may not reach both longitudinal ends easily depending on the phase of the stirring member 34. In other words, the configuration in which the problem of the present invention may occur is not limited to the above-mentioned configuration shown in this embodiment.

[0081] In addition, if the vertical width (height direction) of the toner storage chamber 32d is sufficiently large, and a sufficient distance can be secured between the tip of the blade portion 34b and the introduction port 32c even when the tip of the blade portion 34b is located in the first quadrant, that is, if there is a space for the new toner to spread out in the longitudinal direction outside the orbit of the stirring member 34 (the tip of the blade portion 34b), the above-mentioned new toner and old toner can be mixed. The time required for mixing the toner is unlikely to be an issue. However, in order to provide such a space, it is necessary to increase the vertical width of the toner storage chamber 32d, which may increase the size of the device body. In the developing container 32 of this embodiment, the inlet 32c is opened at the same height as the area where the tip of the blade portion 34b can contact the upper surface of the inner wall surface of the toner storage chamber 32d, so that the size of the device body in the vertical direction of the device is not increased. That is, according to this embodiment, in the configuration of the developing container 32 that is compact and does not have a sufficient distance between the tip of the blade portion 34b of the stirring member 34 located in the first quadrant and the inlet 32c, it is possible to shorten the time required for mixing the new toner and the old toner.

[0082] Example 2 Second Embodiment A second embodiment of the present invention will be described with reference to Figures 9(a) to 9(c). Figure 9 is a cross-sectional view of a developing container 32 in the second embodiment.

[0083] In the second embodiment, the stirring member 34 has a plurality of blades in order to more quickly and uniformly mix the new and old toners during replenishment. The configuration of the stirring member 34 in the image forming apparatus according to the second embodiment other than the blades is the same as that of the image forming apparatus described in the first embodiment, and therefore the description thereof will be omitted.

[0084] In this embodiment, the stirring member 34 has a first blade portion 34b1 and a second blade portion 34b2. The first blade portion 34b1 and the second blade portion 34b2 are members of the same shape made of polycarbonate. The second blade portion 34b2 is installed at a position shifted 90° downstream in the rotation direction from the first blade portion 34b1.

[0085] Specifically, the agitator shaft 34a has a first mounting surface 34a1 extending in the direction of the rotation axis, and a second mounting surface 34a2 extending in the direction of the rotation axis at a position different from the first mounting surface 34a1 around the rotation axis. The first mounting surface 34a1 and the second mounting surface 34a2 are adjacent two of four surfaces aligned in the rotation direction of the agitator shaft 34a having a rectangular cross section, and the directions in which the perpendicular lines (normal lines) extend are perpendicular to each other. The first blade portion (first sheet) 34b1 has a first mounting portion 34b11 that contacts the first mounting surface 34a1. One end (first end) 34b1e1 of the first blade portion 34b1 in the direction perpendicular to the rotation axis is fixed to the agitator shaft 34a as a part of the mounting portion 34b11, and the other end (second end) 34b1e2 is capable of contacting the inner wall surface of the toner storage chamber 32d. The second blade portion (second sheet) 34b2 has an attachment portion (second attachment portion) 34b21 that contacts the second attachment surface 34a2. The second blade portion 34b2 has one end (third end) 34b2e1 in a direction perpendicular to the rotation axis fixed to the agitator shaft 34a as part of the attachment portion 34b21, and the other end (fourth end) 34b2e2 that can contact the toner storage chamber 32d.

[0086] When there is a large amount of toner in the developing container 32, the first blade portion 34b1 may bend more due to the resistance of the toner. When the first blade portion 34b1 is bent, toner (Y in the figure) may remain even after passing the bottom of the developing container 32. The toner Y at the bottom is mixed with the falling toner when the toner scraped off by the first blade portion 34b1 next falls toward the bottom, but compared to when the toner Y at the bottom does not remain, it may take longer for the new toner and the old toner to become uniformly mixed after new toner is replenished.

[0087] In this embodiment, the second blade portion 34b2, which is located 90° downstream of the first blade portion 34b1, can scrape off the toner Y at the bottom that remains after the first blade portion 34b1 has passed. That is, in this embodiment, the toner Y is also sent to the development opening 39. Since the mixing of the toner Y is actively promoted in this development opening 39, the stirring of the entire toner in the development container 32 progresses quickly. Even immediately after replenishment, the presence of the second blade portion 34b2 shortens the time it takes for the replenished new toner and the old toner in the development container 32 to be uniformly mixed. do.

[0088] (Regarding the phase of the blade and the mixture state of new and old toner during replenishment in Example 2) In the configuration with two blades as in Example 2, the control unit 90 controls the rotation of the agitation shaft 34a so that both ends of the two blades are located in a quadrant different from the quadrant in which the inlet 32c is located in the coordinate system, in the same manner as in Example 1. That is, by adjusting the phase so that the supply is performed when the tip positions of both blades 34b1 and 34b2 are located far from the inlet 32c during supply, the same effect as that described in Example 1 can be obtained.

[0089] Fig. 9(a) shows a case where new toner is supplied when the tip positions of the two blades 34b1 and 34b2 are located far from the inlet 32c, Fig. 9(b) shows a case where new toner is supplied when the tip of the first blade 34b1 is located toward the inlet 32c, and Fig. 9(c) shows a case where new toner is supplied when the tip of the second blade 34b2 is located toward the inlet 32c.

[0090] 9(a), if new toner is supplied when the tip positions of the blade portions 34b1 and 34b2 are located far from the inlet 32c, the presence of the second blade portion 34b2 prevents the new toner from penetrating into the bottom surface of the developing container 32. However, since neither the blade portion 34b1 nor the blade portion 34b2 blocks the space into which new toner from the toner pack 40 is supplied into the developing container 32, the new toner is discharged into a sufficiently wide space. As a result, the new toner enters the developing container 32 while spreading over the entire longitudinal area.

[0091] 9(b) or 9(c), if new toner is replenished when the tip of either the blade portion 34b1 or the blade portion 34b2 is located on the inlet 32c side, the blade portion 34b1 or the blade portion 34b2 blocks the space into which the new toner enters. Therefore, the new toner is discharged into a narrow space, causing clogging of the discharged new toner, and the new toner remains in the developer container 32 near the protrusion 38 in the longitudinal direction.

[0092] In Example 2, as shown in Fig. 9(a), when the stirring member 34 was driven in a state in which the new toner was instantly spread in the longitudinal direction immediately after replenishment, the new toner was uniformed after 5 seconds (after 5 rotations of the stirring member 34). It was also confirmed that in this state, no transfer failure occurred after replenishment.

[0093] Example 3 An image forming apparatus according to a third embodiment will be described with reference to Figs. 10(a) to 11(b). In the second embodiment, the two blades 34b1 and 34b2 are made of the same shape and material, but this is not limited thereto. In this embodiment, a preferred configuration will be described for the developing container 32 in which a toner remaining amount sensor (developer remaining amount detection unit) 50, which is an optical detection means for optically detecting the remaining amount, is installed inside the developing container 32. Figs. 10(a) and 10(b) are schematic cross-sectional views of the developing container 32 in a comparative example in which the toner remaining amount sensor 50 is provided in a configuration in which the stirring member 34 has one blade 34b as in the first embodiment. Figs. 11(a) and 11(b) are schematic cross-sectional views of the developing container 32 in a third embodiment in which the toner remaining amount sensor 50 is provided in a configuration in which the stirring member 34 has two blades 34b3 and 34b4 as in the second embodiment.

[0094] Unlike the two blades 34b1 and 34b2 of Example 2, the two blades 34b3 and 34b4 of Example 3 are attached to one mounting surface of the agitator shaft 34a so as to overlap each other. Specifically, the agitator shaft 34a has a mounting surface 34a1 extending in the direction of the rotation axis, and the blade (fourth sheet) 34b4 has a mounting portion 34b41 (fourth mounting portion) that contacts the mounting surface 34a1. The blade 34b4 has one end (seventh end) in a direction perpendicular to the rotation axis. The blade portion (third sheet) 34b3 has an attachment portion 34b31 (third attachment portion) that is attached so as to be overlapped with the attachment portion 34b41 of the blade portion 34b4. The blade portion 34b3 has one end (fifth end) 34b3e1 in a direction perpendicular to the rotation axis fixed to the agitation shaft 34a as a part of the attachment portion 34b31, and the other end (sixth end) 34b3e2 that is capable of contacting the inner wall surface of the toner storage chamber 32d.

[0095] The short side length of the blade portion 34b (the length of the blade portion 34b from the fixed end fixed to the stirring shaft 34a to the free end on the opposite side) is usually set to a length necessary for the blade portion 34b to enter the development opening 39 and supply the toner in the development container 32 to the development opening 39. However, as shown in FIG. 10(a), the blade portion 34b may become caught on the remaining toner sensor 50. If the rotation continues further, as shown in FIG. 10(b), the tip of the blade portion 34b may pass through (go over) the remaining toner sensor 50 but may not be able to get under the remaining toner sensor 50, and may not be able to stir the toner (Y' in the figure) below the remaining toner sensor 50.

[0096] In such a case, for example, the short side length of the first blade portion 34b3 (dotted line) is shortened to an extent that it can be placed under the remaining toner sensor 50, as shown in FIG. 11(a).

[0097] The length (third length) of blade 34b3 from attachment portion 34b31 to the tip (third end) that contacts the inner wall surface of toner-accommodating chamber 32d is shorter than the same length (fourth length) of blade 34b4 from attachment portion 34b41 to the tip (fourth end). Here, the above-mentioned length of each blade refers to the length of the blade in the short direction perpendicular to the long direction, and is the length from the attachment portion to the tip measured along the extension direction of the blade when viewed in the direction of the rotation axis.

[0098] The remaining toner amount sensor 50 is located in a quadrant below the quadrant in which the inlet 32c is located in the coordinate system, and is provided so as to protrude from the inner wall of the toner storage chamber 32d. The control unit 90 controls the rotation of the agitator shaft 34a so that the end of the blade portion 34b3 is located in the quadrant in which the remaining toner amount sensor 50 is located in the coordinate system. The length from the mounting portion 34b31 to the tip (third end) of the blade portion 34b3 is a length that allows the tip of the blade portion 34b3 to enter the recess 32d5 (broken circle area in FIG. 11(b)) formed between the lower end of the remaining toner amount sensor 50 and the inner wall surface of the toner storage chamber 32d.

[0099] After the first blade portion 34b3 scrapes off the toner below the remaining toner sensor 50 and sends it to the bottom of the developing container 32, the second blade portion 34b4 agitates the toner at the bottom. With this configuration, it is possible to agitate all the toner and supply it to the developing opening 39.

[0100] In this way, each of the blades 34b may have a different role. By adjusting the phase so that new toner is replenished when all of the blade tips are located far from the inlet 32c, it is possible to obtain the same effect as that described in the first embodiment. Depending on the configuration of the developing container 32, the number, shape, and material of the blades may be appropriately selected to be different from those in the third embodiment.

[0101] (Other Effects in Example 3) Other effects obtained in the third embodiment will be described. After new toner is replenished from the toner pack 40, the old toner and the new toner in the developing container 32 are quickly and uniformly mixed, which not only improves image defects but also improves the accuracy of the remaining toner sensor 50 in detecting the amount of replenished toner.

[0102] The toner remaining amount sensor 50 for detecting the remaining amount of toner is composed of a light emitting portion 50a, a light receiving portion 50b, and a light guide 600 for guiding light from the light emitting portion 50a. Fig. 12(a) is a cross-sectional view of the B-B' surface seen from the rear side of the developing container 32 in Example 3 shown in Fig. 11. The light guide 600 is disposed at the center of the developing container 32 in the longitudinal direction. In this example, the light guide 600 is made of amorphous polystyrene, which has high transparency.

[0103] The CPU 91 of the control unit 90 judges whether the light receiving unit (light receiving element) 50b has received light from the light emitting unit (light emitting element) 50a based on the voltage level input to the toner remaining amount sensor 50. Then, the CPU 91 calculates the length of time during which the toner remaining amount sensor 50 detects light when the toner in the developing container 32 is stirred for a certain period of time by the stirring member 34. The ROM 93 prestores, as a table 96, a toner remaining amount determination threshold value for determining the toner remaining amount from the light detection time of the toner remaining amount sensor 50. The CPU 91 calculates (predicts) the toner remaining amount in the developing container 32 based on the light detection time of the toner remaining amount sensor 50 and the threshold value stored in the table 96.

[0104] (Method of detecting remaining toner amount) 12(b) and 12(c) are perspective views of the light guide 600. Using these figures, a method for detecting the toner amount by the toner remaining amount sensor 50 will be described. FIG. 12(b) is a view seen from the outside of the developing container 32, to which a sensor having a light emitting portion 50a and a light receiving portion 50b is attached. Light from the light emitting portion 50a is received from a light entering portion 611, and the light that passes through the inside of the developing container 32 and emerges from a light exiting portion 621 is received by the light receiving portion 50b. FIG. 12(c) is a view seen from the inside of the developing container 32, in which the light received from the light entering portion 611 is reflected by surfaces 612 and 622 along the optical path Q and is output to the light exiting portion 621.

[0105] The optical path Q is blocked by the toner transported by the agitator 34 when the agitator 34 makes one rotation. The time during which the light is blocked, i.e., the time during which the light receiver 50b does not detect the light from the light emitter 50a, varies depending on the amount of remaining toner.

[0106] That is, when the remaining toner amount is large, the optical path Q is easily blocked by the toner, so that the time during which the light receiving portion 50b receives light becomes shorter and the intensity of the light received by the light receiving portion 50b becomes smaller.

[0107] On the other hand, when the remaining toner is low, the time that the light receiving portion 50b receives light becomes longer, and the intensity of the light received by the light receiving portion 50b becomes stronger. Therefore, the CPU 91 of the control portion 90 can determine the remaining toner level based on the light receiving time and light receiving intensity of the light receiving portion 50b. The toner remaining amount determination threshold value for determining the remaining toner amount from the light receiving time of the light receiving portion 50b is stored in advance in the ROM 93 as, for example, a table.

[0108] (Detection of remaining toner when refilling new toner from toner pack 40) When detecting the amount of remaining toner when new toner is replenished from the toner pack 40, the accuracy of detecting the amount of remaining toner may be reduced depending on the mixture state of the replenished new toner and the old toner in the developing container 32.

[0109] As described above, new toner has a higher charging ability than old toner. Meanwhile, the inner surfaces 612 and 622 of the light guide 600 on the developing container 32 are charged by repeated rubbing with the toner and the stirring member 34. For this reason, the more highly charged the toner is, the more likely it is to adhere to the surfaces 612 and 622 of the light guide 600, and the surfaces 612 and 622 of the light guide 600 are always blocked by the toner, resulting in poor accuracy in detecting the remaining toner amount. It is easy to decrease.

[0110] Therefore, if the mixture of old toner and new toner after replenishment in the developing container 32 is not uniform, the toner may easily adhere to surfaces 612 and 622 of the light guide 600 in areas where a large amount of new toner is present, which may reduce the accuracy of detecting the remaining toner amount.

[0111] On the other hand, when the mixture of the old toner and the new toner after replenishment in the developing container 32 becomes uniform, there is no part where the new toner is unevenly distributed, and the concentration of the new toner relative to the total toner amount can be made low overall. Therefore, the adhesion of the new toner to the surfaces 612 and 622 of the light guide 600 can be suppressed.

[0112] In other words, if the new toner after replenishment is uniformly mixed with the old toner in the developing container, it is possible to suppress a decrease in the accuracy of remaining toner amount detection.

[0113] (Mixed state of new and old toner after replenishment in this embodiment) 13(a) to 14(d) show images seen from the cross section side and the front side of new toner (hatched area) supplied from toner pack 40 in this embodiment and old toner (filled in area) in developing container 32. These show how the new toner was actually inserted, as confirmed from the front side, by preparing a transparent developing container and using yellow toner as the new toner in toner pack 40 and black toner as the old toner in the transparent developing container 32.

[0114] "Immediately after replenishment" here means before the agitator 34 starts to rotate. The image diagrams viewed from the front also show the state immediately after replenishment, 5 seconds after the agitator 34 starts to rotate (after 5 rotations of the agitator 34), and 20 seconds after (after 20 rotations of the agitator 34). The solid areas indicate areas where the proportion of old toner is high, the shaded areas indicate areas where the proportion of new toner is high, and the dotted areas indicate areas where the new toner and old toner are well mixed together.

[0115] Figures 13(a) to 13(d) show the case where replenishment is performed when the tip position of the blade portion 34b is located farthest from the inlet 32c, while Figures 14(a) to 14(d) show the case where replenishment is performed when the tip position of the blade portion 34b is located on the inlet 32c side.

[0116] As shown in Figures 13(a) to 13(d), when the new toner is replenished when the tip position of the blade portion 34b is located at the farthest position from the inlet 32c at the time of replenishment, the new toner is discharged into a sufficiently wide space and falls to the bottom surface inside the developing container 32, spreading out in the longitudinal direction as if collapsing into a mountain.

[0117] However, on the other hand, as shown in Figures 14(a) to 14(d), if new toner is replenished when the tip position of the blade portion 34b is located on the inlet 32c side at the time of replenishment, the new toner will be ejected all at once into a narrow space, and will remain at the protrusion 38 directly below the replenishment port 32a.

[0118] When the agitator 34 is driven, as shown in Figures 14(a) to 14(d), if the tip of the blade portion 34b is positioned on the inlet 32c side when the toner is replenished and the new toner remains near the inlet 32c in the longitudinal direction inside the developing container 32, it takes more than 20 seconds (20 rotations of the agitator 34) for the new toner to spread throughout the entire longitudinal area, even if the agitator 34 is driven.

[0119] That is, in the case of FIG. 14(a) to FIG. 14(d), after 5 seconds (5 rotations of the stirring member 34), However, the state where new toner remains on the inlet 32c side is not resolved, and there are areas where the proportion of new toner is high (waved line area). When the state where the proportion of new toner is high in the central area where the toner remaining amount sensor 50 is located occurs, new toner adheres to the inner surfaces 612 and 622 of the light guide 600 on the developing container 32, reducing the accuracy of remaining amount detection. It is necessary to perform remaining amount detection after 20 seconds or more have elapsed, during which time the new toner has spread over the entire longitudinal area, and this means that the user has to wait until the image forming apparatus 1 is ready for use after new toner has been replenished.

[0120] Therefore, according to this embodiment, as shown in Figures 13(a) to 13(d), it is possible to replenish the toner when the tip of the blade portion 34b is located at the farthest position from the inlet 32c. Since the new toner instantly spreads in the longitudinal direction inside the developing container 32 immediately after replenishment, the new toner and the old toner become uniform in about 5 seconds (5 rotations of the stirring member 34). Since it is possible to prevent the new toner from adhering to the light guide 600 even at the 5-second mark, and the accuracy of remaining toner detection is unlikely to decrease, it is possible to shorten the time the user has to wait after replenishment.

[0121] In the configuration shown in this embodiment, only the configuration in which the blade portion 34b is provided on the stirring shaft 34a of the stirring member 34 has been shown, but the present invention is not limited to this.

[0122] For example, there is a configuration in which a cleaning member is installed in the longitudinal center to clean the remaining toner sensor 50. A cleaning member that is only located in the longitudinal center does not significantly block the space into which new toner is discharged when toner is replenished. Therefore, even in a configuration in which a cleaning member is provided, if the tip of the blade portion 34b is positioned away from the introduction port 32c before replenishment, new toner in the toner pack 40 is discharged into a sufficiently wide space during replenishment and enters the developing container 32 while spreading out in the longitudinal direction, thereby achieving the same effect as described above.

[0123] In addition, a T-seal for covering the developer opening 39 and sealing the toner in the toner storage chamber is configured to rotate along the agitator shaft 34a so that the toner does not leak during transportation of an unused image forming apparatus 1. The T-seal is, for example, a PET sheet having a thickness of about 45 um and an easy-peel film made of multi-layered polystyrene laminated thereon. The easy-peel film may be, for example, AE300 manufactured by Sumika Plastec Co., Ltd. The T-seal is wider in the longitudinal direction than the developer opening 39, and in an unused image forming apparatus 1, the easy-peel side surface completely covers the developer opening 39, sealing the toner in the developer container 32 so that it does not leak to the developer roller 31 or the supply roller 33 side.

[0124] The T-seal is attached to the agitation shaft 34a of the agitation member 34, and when the image forming apparatus 1 is turned on for the first time at the user's site and the motor starts to rotate, the T-seal is taken up by the rotation of the agitation shaft 34a and peeled off from the developing opening 39. In this state, the T-seal is attached to the agitation shaft 34a of the agitation member 34 and rotates together with the blade portion 34b.

[0125] However, the T seal is thinner than the blade portion 34b and has a smaller elasticity, so it does not agitate the toner or send the toner to the development opening 39 like the blade portion 34b. Even if the tip of the T seal is located at the inlet 32c when new toner is replenished and the T seal is present in the path where the new toner enters the development container 32, the T seal falls due to the force of the new toner falling and does not hinder the entry of the new toner. In other words, even if the tip of the T seal is located at the inlet 32c, the new toner can spread and enter over the entire area in the longitudinal direction of the development container 32. In other words, even if the T seal is configured to rotate along the agitation shaft 34a, if the tip of the blade portion 34b is positioned away from the inlet 32c before replenishment, the new toner in the toner pack 40 is discharged into a sufficiently wide space during replenishment and spreads and enters the development container 32 in the longitudinal direction, so that the same effect as described above can be achieved.

[0126] In this way, members with various functions may be installed in the agitating member 34, but the same effect as described above can be achieved by positioning the tip of a member such as the blade portion 34b, which has high elasticity and has the function of agitating the toner and sending it to the development opening 39, away from the inlet 32c during replenishment.

[0127] The configurations and control methods of the above-described embodiments can be combined with each other as much as possible.

[0128] The disclosure of the embodiments of the present invention includes the following configurations. (Configuration 1) An image forming apparatus to which a toner container can be attached, A photosensitive drum; a developing roller for supplying toner to the photosensitive drum; a mounting portion into which the toner container can be mounted so that a portion of the toner container is exposed to the outside of the image forming apparatus, the mounting portion being provided with a refill port through which toner is replenished in the toner container; a frame having a developing chamber in which the developing roller is disposed, and a storage chamber in which toner is stored and which is connected to the developing chamber and has a storage chamber opening that can communicate with the supply port; The stirring member is provided in the storage chamber, and includes a rotating shaft that rotates around a rotation axis, a first end that is one end in a direction perpendicular to the rotation axis, and a second end that is a sheet having a second end that is capable of contacting an inner wall of the toner storage chamber, the agitating member rotating to agitate the toner stored in the toner storage chamber; A control unit for controlling the rotation of the stirring member; Equipped with When viewed in the direction of the rotation axis, in a two-dimensional coordinate system formed by a first virtual line passing through the rotation axis and extending in a horizontal direction, and a second virtual line passing through the rotation axis and extending in a gravity direction, at least a portion of the storage chamber opening is disposed in a first quadrant or a second quadrant; The control unit controls the stirring member to stop rotating when toner is replenished from the toner container to the storage chamber so that at least a portion of the second end of the sheet is located in a quadrant in the coordinate system different from the quadrant in which the storage chamber opening is located by the time the toner passes through the storage chamber opening. (Configuration 2) the chamber opening is disposed in the first quadrant of the coordinate system when viewed in the direction of the rotation axis; The image forming apparatus according to configuration 1, wherein the control unit controls the stirring member so that the stirring member stops rotating in a state in which the portion of the sheet is located in a third quadrant of the coordinate system at the timing. (Configuration 3) The image forming apparatus described in configuration 1 or 2, characterized in that the storage chamber opening is located in the first quadrant of the coordinate system when viewed in the direction of the rotation axis, and the stirring member is controlled so that the rotation is stopped when the portion of the sheet is located in the second or fourth quadrant. (Configuration 4) The image forming apparatus according to any one of configurations 1 to 3, characterized in that, when viewed in the direction of the rotation axis, the storage chamber opening is located in one of the first quadrant and the second quadrant in the coordinate system, and the photosensitive drum is located in the other quadrant. (Configuration 5) The stirring member has the sheet as a first sheet and further has a second sheet different from the first sheet, The second sheet has a third end, which is one end in a direction perpendicular to the rotation axis, fixed to the rotation shaft at a position around the rotation axis different from the first end of the first sheet, and the other end a fourth end portion which is a portion of the housing and which is capable of contacting an inner wall of the housing chamber; The image forming apparatus according to any one of configurations 1 to 4, characterized in that the control unit controls the stirring member so that by the timing, both at least a portion of the second end of the first sheet and a portion of the second sheet including at least the fourth end are located in a quadrant in the coordinate system different from the quadrant in which the storage chamber opening is located. (Configuration 6) The rotating shaft has a first mounting surface and a second mounting surface, a perpendicular line of the first mounting surface and a perpendicular line of the second mounting surface are perpendicular to each other, the first sheet is attached to the rotating shaft such that a portion including the first end is in contact with the first mounting surface, The image forming apparatus according to any one of configurations 1 to 5, wherein the second sheet is attached to the rotating shaft so that a portion including the third end is in contact with the second mounting surface. (Configuration 7) a remaining amount detection portion that detects the amount of developer contained in the container, the remaining amount detection portion being provided so as to protrude from an inner wall of the container; the stirring member has the sheet as a third sheet, the first end as a fifth end, the second end as a sixth end, and further has a fourth sheet different from the third sheet; the fourth sheet has a seventh end, which is one end in a direction perpendicular to the rotation axis, fixed to the rotation shaft, and an eighth end, which is the other end, capable of contacting an inner wall of the storage chamber; The rotating shaft has a mounting surface extending in a direction of the rotation axis, the fourth sheet is attached to the rotating shaft such that a fourth attachment portion, which is a portion including the seventh end, contacts the attachment surface; the third sheet is attached to the rotating shaft such that a third attachment portion, which is a portion including the fifth end portion, is overlapped with the fourth attachment portion; the remaining amount detection unit is located in a quadrant below a quadrant in the coordinate system in which at least a portion of the storage chamber opening is located, When viewed in the direction of the rotation axis of the rotation shaft, a third length from the third mounting portion to the sixth end of the third sheet measured along the extension direction of the third sheet is shorter than a fourth length from the fourth mounting portion to the eighth end of the fourth sheet measured along the extension direction of the fourth sheet, The image forming apparatus according to any one of configurations 1 to 6, characterized in that the control unit controls the stirring member so that, by the timing, a portion of the third sheet including at least the sixth end is located in the quadrant in the coordinate system in which the remaining amount detection unit is located. (Configuration 8) The image forming device described in any one of configurations 1 to 7, characterized in that the third length is a length that enables the sixth end to enter a recess formed between a lower end of the remaining amount detection unit and an inner wall of the storage chamber. (Configuration 9) 9. The image forming apparatus according to any one of configurations 1 to 8, wherein the storage chamber opening is located at an end of the storage chamber in the direction of the rotation axis. (Configuration 10) an exposure unit for exposing the photosensitive drum to light, the supply port is located above an optical path of a laser beam from the exposure means when viewed in the direction of the rotation axis; The image forming apparatus according to any one of configurations 1 to 9, characterized in that the opening of the storage chamber is located below the optical path of the laser light of the exposure means when viewed in the direction of the rotation axis. (Configuration 11) The image forming apparatus according to any one of configurations 1 to 10, characterized in that the supply port and the storage chamber opening are located between the photosensitive drum and the exposure means in a direction perpendicular to the rotation axis and in a direction in which the photosensitive drum and the exposure means are aligned. (Configuration 12) An image forming apparatus according to any one of configurations 1 to 11, characterized in that the storage chamber opening is located at the same height as an area on the upper surface of the inner wall of the storage chamber that can be contacted by the second end of the sheet. (Configuration 13) an opening / closing member that can take an open position in which the mounting portion is exposed to the outside of the image forming apparatus and a closed position in which the mounting portion is not exposed; A sensor that detects an open / close state of the opening / closing member; Equipped with The image forming apparatus according to any one of configurations 1 to 12, characterized in that when the sensor detects that the opening / closing member is in the open position after the image forming operation is completed, the control unit controls the stirring member to stop rotating in a state in which at least a portion of the second end of the sheet is located in a quadrant in the coordinate system different from the quadrant in which the storage chamber opening is located by the time the toner passes through the storage chamber opening. (Configuration 14) a sensor for detecting whether the toner container is attached to the attachment portion, The image forming apparatus according to any one of configurations 1 to 13, characterized in that when the sensor detects that the toner container is attached to the mounting portion, the control unit controls the stirring member so that at least a portion of the second end of the sheet stops rotating in a state in which it is located in a quadrant in the coordinate system different from the quadrant in which the storage chamber opening is located by the time the toner passes through the storage chamber opening. [Explanation of symbols]

[0129] 1... image forming apparatus, 21... photosensitive drum (image carrier), 31... developing roller (developer carrier), 32... developing container, 32a supply port (developer receiving port), 32c... introduction port (developer introduction port), 32d... toner storage chamber (developer storage chamber), 34... stirring member, 34a... stirring shaft, 34b... blade portion, 39... developing opening, 40... supply container (toner pack)

Claims

1. An image forming apparatus to which a toner container can be attached, A photosensitive drum; a developing roller for supplying toner to the photosensitive drum; a mounting portion into which the toner container can be mounted so that a portion of the toner container is exposed to the outside of the image forming apparatus, the mounting portion being provided with a refill port through which toner is replenished in the toner container; a frame having a developing chamber in which the developing roller is disposed, and a storage chamber in which toner is stored and which is connected to the developing chamber and has a storage chamber opening that can communicate with the supply port; The stirring member is provided in the storage chamber, and includes a rotating shaft that rotates around a rotation axis, a first end that is one end in a direction perpendicular to the rotation axis, and a second end that is a sheet having a second end that is in contact with an inner wall of the toner storage chamber, the sheet rotating to agitate the toner stored in the toner storage chamber; A control unit for controlling the rotation of the stirring member; Equipped with When viewed in the direction of the rotation axis, in a two-dimensional coordinate system formed by a first virtual line passing through the rotation axis and extending in a horizontal direction, and a second virtual line passing through the rotation axis and extending in a gravity direction, at least a portion of the storage chamber opening is disposed in a first quadrant or a second quadrant, The control unit controls the stirring member to stop rotating when toner is replenished from the toner container to the storage chamber so that at least a portion of the second end of the sheet is located in a quadrant in the coordinate system other than the quadrant in which the storage chamber opening is located by the time the toner passes through the storage chamber opening.

2. the chamber opening is disposed in the first quadrant of the coordinate system when viewed in the direction of the rotation axis; The image forming apparatus according to claim 1 , wherein the control unit controls the stirring member so that the part of the sheet stops rotating in a state where the part is located in a third quadrant of the coordinate system by the timing.

3. The image forming apparatus according to claim 1, characterized in that the storage chamber opening is located in the first quadrant of the coordinate system when viewed in the direction of the rotation axis, and the stirring member is controlled so that the rotation is stopped when the portion of the sheet is located in the second or fourth quadrant.

4. 2. The image forming apparatus according to claim 1, wherein the opening of the storage chamber is located in one of the first and second quadrants in the coordinate system when viewed in the direction of the rotation axis, and the photosensitive drum is located in the other quadrant.

5. The stirring member has the sheet as a first sheet and further has a second sheet different from the first sheet, a third end portion of the second sheet, which is one end portion in a direction perpendicular to the rotation axis, is fixed to the rotation axis at a position around the rotation axis different from the first end portion of the first sheet, and a fourth end portion, which is the other end portion, is capable of contacting an inner wall of the storage chamber; The image forming apparatus according to claim 1, characterized in that the control unit controls the stirring member so that, by the timing, both at least a portion of the second end of the first sheet and a portion of the second sheet including at least the fourth end are stopped rotating in a state where they are located in a quadrant in the coordinate system different from the quadrant in which the storage chamber opening is located.

6. The rotating shaft has a first mounting surface and a second mounting surface, a perpendicular line of the first mounting surface and a perpendicular line of the second mounting surface are perpendicular to each other, the first sheet is attached to the rotating shaft such that a portion including the first end is in contact with the first mounting surface, 6. The image forming apparatus according to claim 5, wherein the second sheet is attached to the rotating shaft such that a portion including the third end is in contact with the second attachment surface.

7. a remaining amount detection portion that detects the amount of developer contained in the container, the remaining amount detection portion being provided so as to protrude from an inner wall of the container; the stirring member has the sheet as a third sheet, the first end as a fifth end, the second end as a sixth end, and further has a fourth sheet different from the third sheet; the fourth sheet has a seventh end, which is one end in a direction perpendicular to the rotation axis, fixed to the rotation shaft, and an eighth end, which is the other end, capable of contacting an inner wall of the storage chamber; The rotating shaft has a mounting surface extending in a direction of the rotation axis, the fourth seat is attached to the rotating shaft such that a fourth attachment portion, which is a portion including the seventh end, is in contact with the attachment surface, the third sheet is attached to the rotating shaft such that a third attachment portion, which is a portion including the fifth end portion, is overlapped with the fourth attachment portion; the remaining amount detection unit is located in a quadrant below a quadrant in the coordinate system in which at least a portion of the storage chamber opening is located, When viewed in a direction of a rotation axis of the rotation shaft, a third length from the third mounting portion to the sixth end of the third sheet measured along the extension direction of the third sheet is shorter than a fourth length from the fourth mounting portion to the eighth end of the fourth sheet measured along the extension direction of the fourth sheet, The image forming apparatus according to claim 1, characterized in that the control unit controls the stirring member so that, by the timing, at least a portion of the third sheet including the sixth end is positioned in the quadrant in the coordinate system in which the remaining amount detection unit is located, and stops rotating.

8. 8. The image forming apparatus according to claim 7, wherein the third length is a length that enables the sixth end to enter a recess formed between a lower end of the remaining amount detection portion and an inner wall of the storage chamber.

9. 2. The image forming apparatus according to claim 1, wherein the opening of the storage chamber is located at an end of the storage chamber in the direction of the rotation axis.

10. an exposure unit for exposing the photosensitive drum to light, the supply port is located above an optical path of a laser beam from the exposure means when viewed in the direction of the rotation axis; 10. The image forming apparatus according to claim 9, wherein the opening of the accommodation chamber is located below an optical path of the laser light from the exposure means when viewed in the direction of the rotation axis.

11. 11. The image forming apparatus according to claim 10, wherein the supply port and the storage chamber opening are located between the photosensitive drum and the exposure means in a direction perpendicular to the rotation axis and in a direction in which the photosensitive drum and the exposure means are aligned.

12. 12. The image forming apparatus according to claim 11, wherein the opening of the storage chamber is located at the same height as an area of ​​an upper surface of an inner wall of the storage chamber that can be contacted by the second end of the sheet.

13. an opening / closing member that can take an open position in which the mounting portion is exposed to the outside of the image forming apparatus and a closed position in which the mounting portion is not exposed; A sensor that detects an open / close state of the opening / closing member; Equipped with The image forming apparatus according to claim 1, characterized in that when the sensor detects that the opening / closing member is in the open position after the image forming operation is completed, the control unit controls the stirring member to stop rotating in a state in which at least a portion of the second end of the sheet is located in a quadrant in the coordinate system different from the quadrant in which the storage chamber opening is located by the time the toner passes through the storage chamber opening.

14. a sensor for detecting whether the toner container is attached to the attachment portion, The image forming apparatus according to claim 1, characterized in that, when the sensor detects that the toner container is attached to the mounting portion, the control unit controls the stirring member so that, by the time the toner passes through the storage chamber opening, at least a portion of the second end of the sheet is located in a quadrant in the coordinate system other than the quadrant in which the storage chamber opening is located.

Images